55 results on '"Raul Rivera"'
Search Results
2. Clover frost‐seeding rate effects on productivity and nutritive value of tall fescue pastures during the year of establishment
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Miguel S. Castillo, Perejitei E. Bekewe, and Raul Rivera
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Agronomy and Crop Science - Published
- 2022
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3. Short-term screening of multiple phytogenic compounds for their potential to modulate chewing behavior, ruminal fermentation profile, and pH in cattle fed grain-rich diets
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Raul Rivera-Chacon, Ezequias Castillo-Lopez, Qendrim Zebeli, Renee M. Petri, Nicole Reisinger, and Sara Ricci
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Rumen ,Ginger Extract ,Garlic Oil ,Total mixed ration ,03 medical and health sciences ,chemistry.chemical_compound ,Animal science ,Genetics ,Animals ,Lactation ,Thymol ,Dairy cattle ,030304 developmental biology ,0303 health sciences ,Meal ,digestive, oral, and skin physiology ,0402 animal and dairy science ,04 agricultural and veterinary sciences ,Hydrogen-Ion Concentration ,Fatty Acids, Volatile ,Animal Feed ,040201 dairy & animal science ,Diet ,Milk ,chemistry ,Fermentation ,Mastication ,Cattle ,Female ,Animal Science and Zoology ,Digestion ,Food Science - Abstract
In cattle, proper rumen functioning and digestion are intimately linked to chewing behavior. Yet, high grain feeding impairs chewing activity, increasing the risk of subacute ruminal acidosis and dysfermentation. This study aimed to screen 9 different phytogenic compounds for their potential to modulate chewing activity, meal size, rumino-reticular short-chain fatty acids (SCFA), and pH during consumption in a first daily meal and shortly thereafter in cattle fed a grain-rich diet. Treatments were control (total mixed ration without phytogenic) or addition of a phytogenic compound at a low or high dose. Phytogenic compounds and doses (all in mg/kg) were angelica root (6.6 and 66), capsaicin (10 and 100), gentian root (6.6 and 66), garlic oil (0.3 and 3), ginger extract (40 and 400), L-menthol (6.7 and 67), mint oil (15.3 and 153), thyme oil (9.4 and 94), and thymol (5 and 50), for the low and high groups, respectively. Before the start of the screening experiment, cows were fed to reach subacute ruminal acidosis conditions, confirmed with the time of ruminal pH5.8 being 655 ± 148.2 min/d. During the screening experiment, the treatments were offered in a controlled meal (2.5 kg of DM for 4 h) as part of the daily diet with 65% concentrate. Each treatment was tested in 4 of the 9 cannulated Holstein cows using an incomplete Latin square design. Ruminal and reticular fluids were sampled before and after each treatment, and data collected before the meal were used as covariates. Chewing and ruminal pH were monitored during the treatment, followed by 2 h of complete feed restriction, and then 4 h of ad libitum feed intake without phytogenic. Data showed that supplementation of angelica root tended to linearly increase rumination time immediately after the first meal when feed was restricted (27.3, 41.9, and 42.6 ± 5.99 min for control, low and high groups, respectively). Capsaicin increased eating time (43.6, 49.4, and 66.4 ± 4.93 min) during consumption but did not affect ruminal total SCFA or mean ruminal pH. Garlic oil reduced the concentration of reticular total SCFA (75.7, 71.3, and 60.1 mM) and tended to decrease ruminal acetate-to-propionate ratio (2.50, 1.78, and 1.87 ± 0.177) with no effect on ruminal pH. The L-menthol affected reticular total SCFA quadratically (76.1, 64.9, and 81.0 ± 4.22%), and ruminal pH responded quadratically when feed was reintroduced ad libitum (6.0, 6.3, and 6.1 ± 0.07). Mint oil did not affect chewing or total SCFA during consumption, but the low dose increased ruminal pH (6.5, 6.7, and 6.5 ± 0.08). Thyme oil tended to lower the severity of ruminal acidosis. Overall, phytogenic compounds demonstrated distinct dose-dependent effects to beneficially influence chewing behavior, modulate fermentation, and mitigate ruminal acidosis in dairy cows under a high-grain challenge diet.
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- 2021
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4. Diet and phytogenic supplementation substantially modulate the salivary proteome in dairy cows
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Ezequias Castillo-Lopez, Cátia Pacífico, Arife Sener-Aydemir, Karin Hummel, Katharina Nöbauer, Sara Ricci, Raul Rivera-Chacon, Nicole Reisinger, Ebrahim Razzazi-Fazeli, Qendrim Zebeli, and Susanne Kreuzer-Redmer
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Biophysics ,Biochemistry - Abstract
Phytogenic compounds may influence salivation or salivary properties. However, their effects on the bovine salivary proteome have not been evaluated. We investigated changes in the bovine salivary proteome due to transition from forage to high-concentrate diet, with and without supplementation with a phytogenic feed additive. Eight non-lactating cows were fed forage, then transitioned to a 65% concentrate diet (DM basis) over a week. Cows were control (n = 4, CON) or supplemented with a phytogenic feed additive (n = 4, PHY). Proteomic analysis was conducted using liquid chromatography coupled with mass spectrometry. We identified 1233 proteins; 878 were bovine proteins, 189 corresponded to bacteria, and 166 were plant proteins. Between forage and high-concentrate, 139 proteins were differentially abundant (P 0.05), with 48 proteins having a log2FC difference |2|. The salivary proteome reflected shifts in processes involving nutrient utilization, body tissue accretion, and immune response. Between PHY and CON, 195 proteins were differently abundant (P 0.05), with 37 having a log2FC difference |2|; 86 proteins were increased by PHY, including proteins involved in smell recognition. Many differentially abundant proteins correlated (r |0.70|) with salivary bicarbonate, total mucins or pH. Results provide novel insights into the bovine salivary proteome using a non-invasive approach, and the association of specific proteins with major salivary properties influencing rumen homeostasis. SIGNIFICANCE: Phytogenic compounds may stimulate salivation due to their olfactory properties, but their effects on the salivary proteome have not been investigated. We investigated the effect of high-concentrate diets and supplementation with a phytogenic additive on the salivary proteome of cows. We show that analysis of cows' saliva can be a non-invasive approach to detect effects occurring not only in the gut, but also systemically including indications for gut health and immune response. Thus, results provide unique insights into the bovine salivary proteome, and will have a crucial contribution to further understand animal response in terms of nutrient utilization and immune activity due to the change from forage to a high-energy diet. Additionally, our findings reveal changes due to supplementation with a phytogenic feed additive with regard to health and olfactory stimulation. Furthermore, findings suggest an association between salivary proteins and other components like bicarbonate content.
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- 2022
5. Quality of Service in Software Defined Networks for Scientific Applications: Opportunities and Challenges
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Mabel Vazquez-Briseno, Juan I. Nieto-Hipolito, Salvador Villarreal-Reyes, J. E. Lozano-Rizk, Raul Rivera-Rodriguez, and Alejandro Galaviz-Mosqueda
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Job scheduler ,business.industry ,Process (engineering) ,Computer science ,Quality of service ,Big data ,020207 software engineering ,0102 computer and information sciences ,02 engineering and technology ,computer.software_genre ,01 natural sciences ,010201 computation theory & mathematics ,Order (exchange) ,0202 electrical engineering, electronic engineering, information engineering ,business ,Software-defined networking ,computer ,Software ,Computer network - Abstract
Scientific applications requires to process, analyze and transfer large volumes of data in the shortest possible time from distributed data sources. In order to improve their performance, it is necessary to provide them with specific QoS parameters. On the other hand, SDN is presented as a new paradigm of communications networks that facilitates the management of the communications infrastructure and consequently allows to dynamically incorporate QoS parameters to the applications running in this type of network. With both these paradigms in mind, we conducted this research to answer the following questions: Do scientific applications that are running in an SDN-Enabled distributed data centers improve their performance? Do they consider network QoS parameters for job scheduling? The methodology used was to consult articles in specialized databases containing the keywords SDN and for scientific applications: HPC and Big Data. Then, we analyzed the articles where these keywords intersect with some of the parameters related to QoS in communications networks. Also, we reviewed QoS proposals in SDN to identify the advances in this research area. The results of this paper are: i) QoS is an open issue to incorporate in scientific applications that are running in an SDN ii) we identified the challenges to join both these paradigms, and iii) we present a strategy to provide QoS to scientific applications that are being executed among SDN-Enabled distributed data centers.
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- 2020
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6. Scalable Data Storage Design for Nonstationary IoT Environment With Adaptive Security and Reliability
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Andrei Tchernykh, Nikolay I. Chervyakov, Mikhail Babenko, Vanessa Miranda-Lopez, Arutyun Avetisyan, Gleb Radchenko, Raul Rivera-Rodriguez, Zhihui Du, and Alexander Yu. Drozdov
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Computer Networks and Communications ,business.industry ,Computer science ,Distributed computing ,Homomorphic encryption ,Data security ,020206 networking & telecommunications ,Cloud computing ,Cryptography ,02 engineering and technology ,Data loss ,Secret sharing ,Computer Science Applications ,Hardware and Architecture ,Data redundancy ,Signal Processing ,Information leakage ,Scalability ,0202 electrical engineering, electronic engineering, information engineering ,Redundancy (engineering) ,020201 artificial intelligence & image processing ,business ,Information Systems - Abstract
Internet-of-Things (IoT) environment has a dynamic nature with high risks of confidentiality, integrity, and availability violations. The loss of information, denial of access, information leakage, collusion, technical failures, and data security breaches are difficult to predict and anticipate in advance. These types of nonstationarity are one of the main issues in the design of the reliable IoT infrastructure capable of mitigating their consequences. It is not sufficient to propose solutions for a given scenario, but mechanisms to adapt the current solution to changes in the environment. In this article, we present a multicloud storage architecture called WA-MRC-RRNS that combines the weighted access scheme, threshold secret sharing, and redundant residue number system with multiple failure detection/recovery mechanisms and homomorphic ciphers. We provide a theoretical analysis of the probability of information loss, data redundancy, speed of encoding/decoding, and show how to dynamically configure parameters to cope with different objective preferences, workloads, and cloud properties. We propose a multiobjective optimization mechanism to adjust redundancy, encryption–decryption speed, and data loss probability. Comprehensive experimental analysis with real data shows that our approach provides a secure way to mitigate the uncertainty of the use of untrusted and not reliable IoT infrastructure.
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- 2020
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7. Progressive microbial adaptation of the bovine rumen and hindgut in response to a step-wise increase in dietary starch and the influence of phytogenic supplementation
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Sara Ricci, Cátia Pacífico, Ezequias Castillo-Lopez, Raul Rivera-Chacon, Heidi E. Schwartz-Zimmermann, Nicole Reisinger, Franz Berthiller, Qendrim Zebeli, and Renee M. Petri
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Microbiology (medical) ,Microbiology - Abstract
Microbial composition and activity in the gastrointestinal tract (GIT) of cattle has important implications for animal health and welfare, driving the focus of research toward ways to modify their function and abundance. However, our understanding of microbial adaption to nutritional changes remains limited. The aim of this study was to examine the progressive mechanisms of adaptation in the rumen and hindgut of cattle receiving increasing amounts of starch with or without dietary supplementation of a blended phytogenic feed additive (PFA; containing menthol, thymol and eugenol). We used 16S rRNA gene amplicon sequencing to assess the microbial composition and predicted metabolic pathways in ruminal solid and liquid digesta, and feces. Furthermore, we employed targeted liquid chromatography-mass spectrometry methods to evaluate rumen fluid metabolites. Results indicated a rapid microbial adaptation to diet change, starting on the second day of starch feeding for the particle associated rumen liquid (PARL) microbes. Solid rumen digesta- and feces-associated microbes started changing from the following day. The PARL niche was the most responsive to dietary changes, with the highest number of taxa and predicted pathways affected by the increase in starch intake, as well as by the phytogenic supplementation. Despite the differences in the microbial composition and metabolic potential of the different GIT niches, all showed similar changes toward carbohydrate metabolism. Metabolite measurement confirmed the high prevalence of glucose and volatile fatty acids (VFAs) in the rumen due to the increased substrate availability and metabolic activity of the microbiota. Families Prevotellaceae, Ruminococcaceae and Lachnospiraceae were found to be positively correlated with carbohydrate metabolism, with the latter two showing wide-ranging predicted metabolic capabilities. Phytogenic supplementation affected low abundant taxa and demonstrated the potential to prevent unwanted implications of feeding high-concentrate diet, such as reduction of microbial diversity. The inclusion of 50% concentrate in the diet caused a major shift in microbial composition and activity in the GIT of cattle. This study demonstrated the ability of microorganisms in various GIT niches to adjust differentially, yet rapidly, to changing dietary conditions, and revealed the potential beneficial effects of supplementation with a PFA during dietary adaptation.
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- 2022
8. Dynamics of chewing and eating behavior, lying behavior, and salivary characteristics associated with duration of high grain feeding in cows with or with no phytogenic supplement
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Ezequias Castillo-Lopez, Raul Rivera-Chacon, Sara Ricci, Behzad Khorrami, Andreas Haselmann, Nicole Reisinger, and Qendrim Zebeli
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Food Animals ,Animal Science and Zoology - Published
- 2023
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9. Systematic review and meta-analysis of changes in quality of life following initiation of buprenorphine for opioid use disorder
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Olivia K. Golan, Rachel Totaram, Elizabeth Perry, Kennicia Fortson, Raul Rivera-Atilano, Rebecca Entress, Matthew Golan, Barbara Andraka-Christou, Daniel Whitaker, and Therese Pigott
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Pharmacology ,Analgesics, Opioid ,Psychiatry and Mental health ,Cognition ,Opiate Substitution Treatment ,Quality of Life ,Humans ,Pharmacology (medical) ,Toxicology ,Opioid-Related Disorders ,Buprenorphine - Abstract
People with opioid use disorder (OUD) experience lower quality of life (QoL) than the general population, but buprenorphine treatment for OUD could help improve QoL of individuals with OUD. Thus, we conducted a systematic review and meta-analysis of the impact of buprenorphine on QoL among people with OUD.Seven databases were searched through August 2020. We included English-language studies with pre- and post- QoL assessments internationally. Standardized mean differences were calculated for five domains of QoL measures using a random effects model for correlated effect sizes with robust variance estimation. Meta-regression was used to assess variation in effect sizes based on QoL domain, treatment, and patient factors.Twenty-one peer-reviewed studies from twelve countries were included. Only three studies included a no-treatment control group and five studies assigned groups using randomization. Improvements between baseline and follow-up were observed across all five domains of QoL measures (overall, physical, psychological, social, and environmental). The certainty of evidence was low for all domains of QoL, and very low for environmental QoL. We did not observe differences in the effect of buprenorphine on QoL by QoL domain, duration, dose, participant characteristics, or adjunctive counseling services.Buprenorphine treatment likely improves overall, physical, psychological, and social QoL, and may improve environmental QoL, for individuals with OUD. Findings are limited by study quality, including lack of control groups and incomplete reporting. Future studies with more rigorous methods and comprehensive reporting are needed.
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- 2022
10. Changes in fermentation profile of the reticulorumen and hindgut, and nutrient digestion in dry cows fed concentrate-rich diets supplemented with a phytogenic feed additive
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Ezequias Castillo-Lopez, Raul Rivera-Chacon, Sara Ricci, Nicole Reisinger, and Qendrim Zebeli
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Dietary Fiber ,Rumen ,Detergents ,Nutrients ,Fatty Acids, Volatile ,Animal Feed ,Diet ,Butyrates ,Milk ,Fermentation ,Genetics ,Animals ,Lactation ,Animal Science and Zoology ,Cattle ,Digestion ,Female ,Food Science - Abstract
This study evaluated the effects of duration of high-concentrate feeding on ruminal and fecal fermentation profile, as well as selected systemic health biomarkers in nonlactating cows supplemented with or without a phytogenic feed additive (PHY). In addition, ruminal degradation kinetics and total-tract nutrient digestibility were evaluated when feeding either only forage or a high-concentrate diet. Nine nonlactating, cannulated Holstein cows were used in a crossover design. Each period included 1 wk of forage feeding (wk 0), diet transition, and 4 wk on the high-concentrate diet (1, 2, 3 and wk 4; 65% dry matter basis). Cows received PHY or not (control). Compared with wk 0, from wk 1 onward, cows on high concentrate showed greater reticular, ruminal, and fecal total volatile fatty acids (VFA), with a greater level of VFA in the rumen than in the hindgut. However, ruminal fermentation was modulated differently by PHY, which showed increased total VFA in wk 1 and increased butyrate in wk 2 in the particle-associated fluid of rumen. In the hindgut, PHY increased propionate in wk 3. Cows fed a high-concentrate diet from wk 1 and onward also showed greater ruminal lactate, as well as lower ruminal and fecal pH, independent of PHY. In addition, compared with cows in wk 1 on a high-concentrate diet, cows in wk 4 had a greater total VFA in free fluid of the rumen and lower fecal pH. Compared with cows at wk 0, cows at wk 1 on high concentrate onward showed greater serum amyloid A and greater activity of glutamate dehydrogenase. In contrast, the high-concentrate diet decreased in situ ruminal degradability of grass silage but increased degradability of corn grain as well as total-tract nutrient digestibility, with total-tract neutral detergent fiber digestibility being greater for cows on the PHY treatment. Overall, from the start of high-concentrate feeding, gut fermentation increased, but differently according to location or PHY, with a stronger build-up of VFA in the rumen compared with the hindgut. In addition, a longer duration on high concentrate exacerbated gut acidification. The enhancing effects of PHY on total VFA and butyrate in particle-associated fluid of the rumen suggest beneficial effects of PHY on particle-associated bacteria, likely contributing to the increased neutral detergent fiber digestibility. The greater production of ruminal butyrate with PHY may be beneficial for the host, given the health benefits of this acid, but more research is needed to elucidate the effects on gut microbiota and the effects of increased butyrate in nonlactating dairy cows.
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- 2022
11. Positional Characteristics for Efficient Number Comparison over the Homomorphic Encryption
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Mikhail Babenko, Viktor Andreevich Kuchukov, Raul Rivera-Rodriguez, Andrei Tchernykh, Zhihui Du, El-Ghazali Talbi, Nikolay I. Chervyakov, and Vanessa Miranda-Lopez
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Cryptographic primitive ,Computer science ,business.industry ,Homomorphic encryption ,020207 software engineering ,0102 computer and information sciences ,02 engineering and technology ,Power of two ,Residue number system ,Operand ,Encryption ,01 natural sciences ,Computer Science::Hardware Architecture ,Finite field ,010201 computation theory & mathematics ,0202 electrical engineering, electronic engineering, information engineering ,Hardware_ARITHMETICANDLOGICSTRUCTURES ,business ,Algorithm ,Software ,Decoding methods - Abstract
Modern algorithms for symmetric and asymmetric encryptions are not suitable to provide security of data that needs data processing. They cannot perform calculations over encrypted data without first decrypting it when risks are high. Residue Number System (RNS) as a homomorphic encryption allows ensuring the confidentiality of the stored information and performing calculations over encrypted data without preliminary decoding but with unacceptable time and resource consumption. An important operation for encrypted data processing is a number comparison. In RNS, it consists of two steps: the computation of the positional characteristic of the number in RNS representation and comparison of its positional characteristics in the positional number system. In this paper, we propose a new efficient method to compute the positional characteristic based on the approximate method. The approximate method as a tool to compare numbers does not require resource-consuming non-modular operations that are replaced by fast bit right shift operations and taking the least significant bits. We prove that in case when the dynamic range of RNS is an odd number, the size of the operands is reduced by the size of the module. If one of the RNS moduli is a power of two, then the size of the operands is less than the dynamic range. We simulate proposed method in the ISE Design Suite environment on the FPGA Xilinx Spartan-6 SP605 and show that it gains 31% in time and 37% in the area on average with respect to the known approximate method. It makes our method efficient for hardware implementation of cryptographic primitives constructed over a prime finite field.
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- 2019
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12. Toward digital twins' workload allocation on clouds with low-cost microservices streaming interaction
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Igor Chernykh, Gleb Radchenko, Jorge M. Cortés-Mendoza, Mikhail Babenko, Raul Rivera-Rodriguez, Igor Kulikov, Sergio Nesmachnow, Andrei Tchernykh, Bernardo Pulido-Gaytan, and Adrian Facio-Medina
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Branch and bound ,business.industry ,Heuristic (computer science) ,Bin packing problem ,Computer science ,Distributed computing ,Cloud computing ,Local search (optimization) ,Microservices ,business ,Heuristics ,Metaheuristic - Abstract
A Digital Twin (DT) is a set of computational models representing real-time physical objects and processes in a digital world. The increasing adoption of this paradigm by the major industrial equipment vendors to simulate real-time working conditions and perform smart decision-making, established the Smart Factory Digital Twins architectures, where a set of DTs published as microservices interact with each other exchanging information by streaming technology. In this sense, a fundamental problem consists of selecting adequate computational resources to simulate the physical objects. In an Infrastructure as a Service (IaaS) cloud for DTs, the allocation focuses on distributing the jobs of the set into the virtual machine instances in a way that computational resources demand is satisfied and the cost is minimized. In this paper, we propose a set of algorithms based on heuristics, metaheuristics, and Mixed Integer Programming to find low-cost solutions. The performance of algorithms is evaluated using Amazon EC2 instances and DT jobs with randomly generated bandwidth, memory, and processor requirements. The experimental results show that the proposed approaches based on bin packing, genetic algorithms, partition, filtering, set coverage, and branch and bound strategies present a competitive performance in the workload allocation of the computational set of jobs of a DT into an IaaS cloud environment. Our allocation heuristic-based techniques allow considerable cost savings in medium and large periods concerning standard approaches such as local search.
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- 2020
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13. Dynamic changes in salivation, salivary composition, and rumen fermentation associated with duration of high-grain feeding in cows
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Nicole Reisinger, Qendrim Zebeli, Arife Sener-Aydemir, Raul Rivera-Chacon, Ezequias Castillo-Lopez, Sara Ricci, Renee M. Petri, and Suchitra Sharma
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Saliva ,Rumen ,Bicarbonate ,03 medical and health sciences ,chemistry.chemical_compound ,Animal science ,Genetics ,Animals ,Lactation ,Dry matter ,030304 developmental biology ,0303 health sciences ,Meal ,digestive, oral, and skin physiology ,0402 animal and dairy science ,04 agricultural and veterinary sciences ,Hydrogen-Ion Concentration ,Fatty Acids, Volatile ,040201 dairy & animal science ,Animal Feed ,Diet ,Neutral Detergent Fiber ,Milk ,chemistry ,Fermentation ,Animal Science and Zoology ,Cattle ,Female ,Lysozyme ,Bolus (digestion) ,Salivation ,Food Science - Abstract
Salivary secretions are essential for the regulation of digestive processes, as well as rumen and cow health. This research evaluated the effects of the duration of high-grain feeding, and of the time relative to a meal, on salivation, saliva properties, feed bolus characteristics, chewing activity, ruminal and reticular volatile fatty acids, as well as salivary and ruminal pH. Nine nonlactating cannulated Holstein cows were sampled at 1 and 23 d after transition to a 65% grain diet (short term and long term, respectively). Both before and after a controlled meal (2.5 kg of dry matter, offered over 4 h), unstimulated saliva was taken orally for composition analysis. Stimulated salivation and feed boli characteristics were evaluated by collection of ingesta from cardia during 30 min. Chewing and ruminal pH were measured during the controlled meal and for a total of 6 h thereafter. Results from unstimulated saliva showed no effect of the duration of high-grain feeding on bicarbonate, phosphate, total proteins, mucins, lysozyme, and buffer capacity, but increased osmolality at the long term. Lysozyme activity did not differ with high-grain feeding duration, but tended to be lower after the meal. In contrast to short-term-fed cows, the long-term-fed cows increased both meal consumption and feed bolus size, but decreased chewing and feed ensalivation (5.2 vs. 4.6 ± 0.50 g of saliva/g of dry matter), and had lower pH of the stimulated saliva (7.00 vs. 6.67 ± 0.076). These cows also had decreased chewing index (66.5 vs. 45.4 min/kg of neutral detergent fiber), and despite the increase in stimulated saliva buffer capacity (0.027 vs. 0.039 ± 0.006), mean ruminal pH decreased (6.31 vs. 6.11 ± 0.065) during ad libitum feeding. Both in the rumen and reticulum, the concentration of total volatile fatty acids was lower and propionate proportion was higher at the long term. Linear regression analyses revealed a positive influence of the flow rates of salivary bicarbonate and phosphate on ruminal pH during the short term. For every 1-mol increment in the flow of bicarbonate or phosphate, ruminal pH increased by 0.062 or 0.439 units, respectively. Overall, salivary buffers are key determinants of ruminal pH regulation, especially during short-term grain feeding. However, in the long term, ruminal pH drop during ad libitum feeding was stronger, and this effect seems to be exacerbated by increased feed bolus size, accompanied by reductions in feed ensalivation, stimulated saliva pH, and chewing index.
- Published
- 2020
14. A Novel Mesh Following Technique Based on a Non-Approximant Surface Reconstruction for Industrial Robotic Path Generation
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Miguel Angel Funes-Lora, Manuel Faraón Carbajal Romero, Raul Rivera Blas, Emmanuel Alejandro Merchán Cruz, Eduardo Vega-Alvarado, and Edgar Alfredo Portilla-Flores
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0209 industrial biotechnology ,General Computer Science ,Computer science ,Point cloud ,02 engineering and technology ,law.invention ,Industrial robot ,020901 industrial engineering & automation ,Software ,surface reconstruction ,law ,0202 electrical engineering, electronic engineering, information engineering ,General Materials Science ,Point (geometry) ,path generation ,business.industry ,General Engineering ,Control engineering ,Robot programming procedure ,Trajectory ,Robot ,020201 artificial intelligence & image processing ,lcsh:Electrical engineering. Electronics. Nuclear engineering ,business ,lcsh:TK1-9971 ,industrial robot - Abstract
Nowadays, industrial robot applications are required to customize the manufacturing of diverse products to reduce both downtime and standoff variability. The two methods for robot programming are regularly implemented to carry out that goal. The first one, online programming, requires a specialized operator to guide the robot through desired poses, and the quality of the result is directly limited by his skill level. On the other side, off-line programming uses software packaging to simulate robot applications before their implementation. It reduces downtime with respect to online programming but requires additional calibration steps. In this paper, a novel procedure is presented to obtain accurate surface approximations by combining linear interpolations generated during online programming with a triangulated surface reconstruction of a workpiece surface representation. The method uses a point cloud instead of a predefined mesh to reduce the standoff variability between the robotic tool center point and the surface. Additionally, a technique based on a penalized least squares method was implemented to smooth the trajectory, including position and orientation. The proposed methodology was validated with three well-known case studies involving real trajectories, with simulations in MATLAB and RobotStudio, as well as by experimentation with an industrial ABB robot. The quality of the results demonstrates a great efficiency of this method for path generation based on surface reconstruction.
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- 2019
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15. Supplementing a Phytogenic Feed Additive Modulates the Risk of Subacute Rumen Acidosis, Rumen Fermentation and Systemic Inflammation in Cattle Fed Acidogenic Diets
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Raul Rivera-Chacon, Ezequias Castillo-Lopez, Sara Ricci, Renee M. Petri, Nicole Reisinger, and Qendrim Zebeli
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General Veterinary ,Animal Science and Zoology ,rumen pH ,high concentrate ,fermentation ,cattle - Abstract
Feeding with high-concentrate diets increases the risk of subacute ruminal acidosis (SARA). This experiment was conducted to evaluate whether supplementing a phytogenic feed additive based on L-menthol, thymol, eugenol, mint oil (Mentha arvensis) and cloves powder (Syzygium aromaticum) (PHY) can amend the ruminal fermentation profile, modulate the risk of SARA and reduce inflammation in cattle. The experiment was designed as a crossover design with nine non-lactating Holstein cows, and was conducted in two experimental runs. In each run, cows were fed a 100% forage diet one week (wk 0), and were then transitioned stepwise over one week (0 to 65% concentrate, wk adapt.) to a high concentrate diet that was fed for 4 weeks. Animals were fed diets either with PHY or without (CON). The PHY group had an increased ruminal pH compared to CON, reduced time to pH < 5.8 in wk 3, which tended to decrease further in wk 4, reduced the ruminal concentration of D-lactate, and tended to decrease total lactate (wk 3). In wk 2, PHY increased acetate, butyrate, isobutyrate, isovalerate, and the acetate to propionate ratio compared to CON. Phytogenic supplementation reduced inflammation compared to CON in wk 3. Overall, PHY had beneficial effects on ruminal fermentation, reduced inflammation, and modulated the risk of SARA starting from wk 3 of supplementation.
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- 2022
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16. Bovine rumen epithelial miRNA-mRNA dynamics reveals post-transcriptional regulation of gene expression upon transition to high-grain feeding and phytogenic supplementation
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Cátia Pacífico, Sara Ricci, Floriana Sajovitz, Ezequias Castillo-Lopez, Raul Rivera-Chacon, Renée Maxine Petri, Qendrim Zebeli, Nicole Reisinger, and Susanne Kreuzer-Redmer
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Genetics - Abstract
The rumen epithelium has a pivotal role in nutrient uptake and host health. This study aimed to explore the role of microRNAs (miRNAs) in the epithelial transcriptome during diet transition from forage to high-grain feeding and the modulation through supplementation with a phytogenic feed additive. Rumen biopsies were collected from 9 ruminally-cannulated non-lactating Holstein cows fed a baseline forage diet (FD) and then transitioned to high-grain feeding (HG; 65% concentrate on a dry matter basis). Cows were randomly allocated into a control group (CON, n = 5) and a group supplemented with a phytogenic feed additive (PHY, n = 4). MiRNA and mRNA sequencing was performed in parallel and transcripts were analyzed for differential expression, pathway enrichment analysis, and miRNA-mRNA interaction networks. We identified 527 miRNAs shared by all samples of the rumen epithelium, from which, bta-miR-21-5p, bta-miR-143 and bta-miR-24-3p were the most expressed. Six miRNAs were differentially expressed between CON and PHY and 8 miRNAs between FD and HG feeding, which were mainly associated with fat metabolism. Transcriptome analysis identified 9481 differentially expressed genes (DEGs) between FD and HG, whereas PHY supplementation resulted in 5 DEGs. DEGs were mainly involved in epithelium development and morphogenesis. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways associated with tricarboxylic acid and short chain fatty acid (SCFA) metabolism were enriched in DEGs between diets. MiRNA target prediction and anti-correlation analysis was used to construct networks and identify DEGs targeted by DE miRNAs responsive to diet or PHY. This study allowed the identification of potential miRNA regulation mechanisms of gene expression during transition from FD to HG feeding and phytogenic supplementation, evidencing a direct role of miRNAs in host responses to nutrition.
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- 2022
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17. An Adaptive Cross-Layer Admission Control Mechanism for Telemedicine Services over the IEEE 802.22/WRAN Standard
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Salvador Villarreal-Reyes, Raul Rivera-Rodriguez, Roberto Conte-Galvan, Roberto Magana-Rodriguez, and Alejandro Galaviz-Mosqueda
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Telemedicine ,IEEE 802.22 ,Computer Networks and Communications ,business.industry ,Computer science ,Quality of service ,Cross layer ,Admission control ,Electrical and Electronic Engineering ,business ,Software ,Mechanism (sociology) ,Computer network - Published
- 2018
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18. 323 Effect of an Acidogenic Diet with Phytogenic Supplementation on in Situ Degradability of Corn and Wheat Grain, and Grass Silage in Dairy Cows
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Raul Rivera-Chacon, Ezequias Castillo-Lopez, Nicole Reisinger, Qendrim Zebeli, and Sara Ricci
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In situ ,Wheat grain ,Acidogenesis ,Animal science ,Silage ,Chemistry ,Genetics ,food and beverages ,Animal Science and Zoology ,General Medicine ,Food Science - Abstract
Modern dairy production systems require larger inputs of energy in diets to increase milk yield. Therefore, dairy cows are at risk of experiencing subacute ruminal acidosis (SARA). The objective of this study was to evaluate grains and forage rumen degradability in cows fed different diets supplemented with a phytogenic (PHY) feed additive. The experiment was conducted with nine rumen-cannulated non-lactating Holstein cows blocked in two groups of four and five animals, and were part of a cross-over design. This study consisted in 2 runs separated by a 12-week washout period, in which cows grazed on pasture. Each experimental run had one week of forage (F) feeding, one week of transition to a high grain (HG) diet, and four weeks of HG (65:35 concentrate to forage ratio in dry matter basis). Cows were supplemented with PHY (a blend of menthol and thymol) or a control carrier (CON) from week F. Corn and wheat grain were ground through a 4 mm screen, while grass silage was ground through a 6 mm screen. Sampling for in situ degradability was performed in F and in week four of HG diet. Data were analyzed with SAS with week of feeding and supplementation as fixed effects and cow as random effect. Corn and wheat 24-h dry matter (DM) and organic matter (OM) degradability increased during HG diet compared with F (P < 0.05), grass silage DM and OM 48-h degradability was reduced by HG diet compared to F (P < 0.01). Additionally, wheat grain 24-h OM degradability was higher for PHY compared to CON under F and HG diet conditions (P = 0.05). Overall, diet composition and SARA conditions can influence grains and fiber degradability in the rumen.
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- 2021
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19. 196 Screening several phytogenic compounds for their effect on ruminal fermentation parameters in cattle fed high grain diet
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Renee M. Petri, Raul Rivera-Chacon, Ezequias Castillo-Lopez, Sara Ricci, Qendrim Zebeli, and Nicole Reisinger
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Abstracts ,Chemistry ,Genetics ,Ruminal fermentation ,food and beverages ,Animal Science and Zoology ,General Medicine ,Food science ,Food Science - Abstract
Phytogenic compounds, e.g. secondary plant compounds and essential oils, are often used as supplements in ruminant nutrition to modulate microbial fermentation under ruminal dysbiosis associated with high grain feeding. The aim of this study was to evaluate the short-term effects of phytogenic compounds on volatile fatty acids (VFA) production and composition in cows affected by subacute ruminal acidosis (SARA). Nine substances were tested at low and high dosage (1x and 10x respectively) using nine non-lactating ruminally cannulated Holstein cows, adapted to a 65% concentrate and 35% silage (grass and corn) ration (DM basis). Feeding was restricted for nine hours before providing the substance mixed with five kg of TMR. Each substance and dosage was tested individually on four cows (n = 4/compound/dose) over a period of four hours. Rumen and reticulum fluid were collected before the treatment, and four hours after feeding. VFA were measured with gas chromatography. Ruminal pH was continuously recorded (eCow indwelling pH systems). Data were analyzed with the Proc Mixed procedure of SAS. Seven out of nine compounds showed an effect or a trend on VFA measured, both in rumen and reticulum. Acetic acid in rumen fluid decreased with garlic oil, while low dose mint oil increased its concentration (P = 0.06 and P = 0.01, respectively). Low dose mint oil (P < 0.01) and L-menthol (P = 0.03) both increased the A:P ratio, whereas garlic oil tended towards a decrease in the A:P ratio. Garlic oil and ginger showed negative correlations between total VFA and mean ruminal pH (P = 0.03 and P < 0.01, respectively). Our results suggest that phytogenic compounds can modulate microbial activity within four hours of feeding. The use of phytogenic compounds may have beneficial effects on microbial fermentation under low pH conditions associated with high grain feeding.
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- 2020
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20. Multi-objective Configuration of a Secured Distributed Cloud Data Storage
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C.J. Barrios-Hernandez, Vanessa Miranda-Lopez, Gleb Radchenko, Arutyun Avetisyan, Andrei Tchernykh, Luis Enrique García-Hernández, Alexander Yu. Drozdov, Harold Castro, Mikhail Babenko, and Raul Rivera-Rodriguez
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business.industry ,Computer science ,Distributed computing ,Approximation algorithm ,Cloud computing ,02 engineering and technology ,Data redundancy ,020204 information systems ,Computer data storage ,Information leakage ,0202 electrical engineering, electronic engineering, information engineering ,020201 artificial intelligence & image processing ,business ,Cloud storage - Abstract
Cloud storage is one of the most popular models of cloud computing. It benefits from a shared set of configurable resources without limitations of local data storage infrastructures. However, it brings several cybersecurity issues. In this work, we address the methods of mitigating risks of confidentiality, integrity, availability, information leakage associated with the information loss/change, technical failures, and denial of access. We rely on a configurable secret sharing scheme and error correction codes based on the Redundant Residue Number System (RRNS). To dynamically configure RRNS parameters to cope with different objective preferences, workloads, and cloud properties, we take into account several conflicting objectives: probability of information loss/change, extraction time, and data redundancy. We propose an approach based on a genetic algorithm that is effective for multi-objective optimization. We implement NSGA-II, SPEA2, and MOCell, using the JMetal 5.6 framework. We provide their experimental analysis using eleven real data cloud storage providers. We show that MOCell algorithm demonstrates best results obtaining a better Pareto optimal front approximation and quality indicators such as inverted generational distance, additive epsilon indicator, and hypervolume. We conclude that multi-objective genetic algorithms could be efficiently used for storage optimization and adaptation in a non-stationary multi-cloud environment.
- Published
- 2020
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21. Recurrent Papillary Thyroid Carcinoma to the Cervical Lymph Nodes: Outcomes of Compartment-Oriented Lymph Node Resection
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Bernardo Pérez-Enríquez, Raul Rivera-Moscoso, Miguel F. Herrera, Juan Pablo Pantoja, Mónica Chapa, David Velázquez-Fernández, Mauricio Sierra, and Carlos Gustavo Rivera-Robledo
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Adult ,Male ,Reoperation ,medicine.medical_specialty ,030230 surgery ,Thyroid carcinoma ,Iodine Radioisotopes ,03 medical and health sciences ,0302 clinical medicine ,Postoperative Complications ,Medicine ,Humans ,Thyroid Neoplasms ,Lymph node ,Thyroid cancer ,Retrospective Studies ,business.industry ,Vascular surgery ,Middle Aged ,medicine.disease ,Surgery ,Dissection ,medicine.anatomical_structure ,Treatment Outcome ,Cervical lymph nodes ,Cardiothoracic surgery ,Thyroid Cancer, Papillary ,030220 oncology & carcinogenesis ,Lymphatic Metastasis ,Thyroidectomy ,Neck Dissection ,Female ,Lymph Nodes ,Neoplasm Recurrence, Local ,business ,Abdominal surgery - Abstract
Recurrence of papillary thyroid carcinoma after initial treatment is challenging. Surgical reintervention is recommended, but cure after surgery in uncertain and surgical morbidity may be high. This study evaluates the effect of compartment-oriented lymph node dissection (LND) on clinical and biochemical cure rate as well as the related complications. All patients who underwent LND for recurrent papillary thyroid carcinoma between 2000 and 2015 were included. Demography, the extent of the initial surgery, usage of 131I, the pattern of recurrence, diagnosis, details of the surgical reintervention, histological findings, surgical morbidity, and clinical and biochemical outcomes were analyzed. There were 11 (12.7%) males and 75 (87.2%) females with a mean age of 42.8 ± 14.6 years. Seventy-seven patients had undergone total thyroidectomy and in 67 (77.9%) some type of LN resection. In 76 (88.3%), 131I was administered after the initial surgery. We localized suspicious lymph nodes by US in all patients, and metastases were documented before surgery by FNA in 63. Seven (8.13%) patients underwent central LND, 63 (73.2%) lateral LND and 16 (18.6%) both, central and lateral LND. Major complications occurred in 6 patients (6.9%). Sixty-two (72.0%) patients received 131I after surgery. A second surgical re-exploration was performed in 30 (34.8%) patients, and 7 patients required 3 or more additional LND. In a mean follow-up of 59.4 ± 39 months, 51 (59.3%) patients are clinically, radiologically and biochemically free of disease. In this series, compartment-oriented lymph node resection of recurrent papillary thyroid carcinoma leads to a final clinical and biochemical disease-free status of 59.3% with 6.9% of major complications.
- Published
- 2019
22. Weighted Two-Levels Secret Sharing Scheme for Multi-Clouds Data Storage with Increased Reliability
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Egor Shiryaev, Mikhail Babenko, Gleb Radchenko, Elena Golimblevskaia, Vanessa Miranda-Lopez, Andrei Tchernykh, Raul Rivera-Rodriguez, Arutyun Avetisyan, Viktor Andreevich Kuchukov, Maxim Deryabin, and El-Ghazali Talbi
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Distributed database ,business.industry ,Computer science ,Reliability (computer networking) ,020206 networking & telecommunications ,Cloud computing ,02 engineering and technology ,Secret sharing ,Data access ,Computer data storage ,Distributed data store ,0202 electrical engineering, electronic engineering, information engineering ,020201 artificial intelligence & image processing ,business ,Cloud storage ,Computer network - Abstract
Cloud storages delivered as services are made available to the general public. As cloud storage provider prices become low, they have moved into the mainstream of storage technology. However, there are various factors that cause many potential users do not use it intensively. There exist high risks for confidentiality, integrity, and availability violation associated with the loss of information, denial of access, technical failures, etc. In this article, we propose a two-level secret sharing scheme (TL-SSS) based on a residue number system (RNS) for a configurable, reliable, and secure distributed data storage. RNS moduli of a special type increase the reliability of the data storage system and reduce the computational complexity of the data encoding and decoding from linear-logarithmic to linear. TL-SSS is the weighted data access structure. It creates and distributes data shares according to the characteristics of the cloud storages under various scenarios. We provide a solution that improves system reliability without reduction of the security level. In contrast to classical solutions, it can restore the data with less available shares than the state-of-the-art approaches.
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- 2019
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23. Data Reliability and Redundancy Optimization of a Secure Multi-cloud Storage Under Uncertainty of Errors and Falsifications
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Viktor Andreevich Kuchukov, Andrei Tchernykh, Vanessa Miranda-Lopez, Gleb Radchenko, Raul Rivera-Rodriguez, Mikhail Babenko, and Arutyun Avetisyan
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Distributed database ,Computer science ,Distributed computing ,020206 networking & telecommunications ,02 engineering and technology ,Data redundancy ,Scalability ,Distributed data store ,Information leakage ,0202 electrical engineering, electronic engineering, information engineering ,Redundancy (engineering) ,020201 artificial intelligence & image processing ,Error detection and correction ,Cloud storage ,Decoding methods - Abstract
Despite all the benefits a cloud data storages offer to customers, there is a high risk of breach of confidentiality, integrity, and availability related with the uncertainty of errors and falsifications, loss of information, denial of access for a long time, information leakage, conspiracy, and technical failures. In this article, we propose a configurable, reliable, and secure distributed data storage scheme with improved data redundancy, reliability, and encoding/decoding speed. Our system utilizes a Polynomial Residue Number System (PRNS) with a new method of error correction codes and secret sharing schemes. We introduce the concept of an approximate value of a rank (AR) of a polynomial. It reduces the computational complexity of the encoding/decoding and PRNS coefficients size. Based on the properties of the approximate value and PRNS, we introduce the AR-PRNS method for error detection, correction, and controlling computational results with capabilities of scalable parallel computing. We provide a theoretical basis to configure and optimize the redundancy of stored data and encoding/decoding speed to cope with different objective preferences, workloads, and storage properties. Theoretical analysis shows that, by appropriate selection of AR-PRNS parameters, the proposed scheme increases the safety, reliability, and reduces the overhead of data storage.
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- 2019
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24. Deep-learning based detection of COVID-19 using lung ultrasound imagery
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Alejandro Galaviz-Mosqueda, Raul Rivera-Rodriguez, Julia Diaz-Escobar, Vitaly Kober, Nelson E. Ordonez-Guillen, Jose E Lozano Rizk, and Salvador Villarreal-Reyes
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Viral Diseases ,Pulmonology ,Wilcoxon signed-rank test ,Computer science ,computer.software_genre ,Diagnostic Radiology ,Medical Conditions ,Ultrasound Imaging ,Image Processing, Computer-Assisted ,Medicine and Health Sciences ,Lung ,Tomography ,Ultrasonography ,Virus Testing ,Multidisciplinary ,Radiology and Imaging ,Ultrasound ,Thorax ,Pulmonary Imaging ,Bone Imaging ,Infectious Diseases ,Pleurae ,Medicine ,Analysis of variance ,Anatomy ,Research Article ,Coronavirus disease 2019 (COVID-19) ,Imaging Techniques ,Science ,Neuroimaging ,Research and Analysis Methods ,Machine learning ,Deep Learning ,Diagnostic Medicine ,medicine ,Humans ,Receiver operating characteristic ,business.industry ,Deep learning ,COVID-19 ,Biology and Life Sciences ,Covid 19 ,Pneumonia ,medicine.disease ,Computed Axial Tomography ,Lung ultrasound ,X-Ray Radiography ,Artificial intelligence ,business ,computer ,Neuroscience - Abstract
BackgroundThe COVID-19 pandemic has exposed the vulnerability of healthcare services worldwide, especially in underdeveloped countries. There is a clear need to develop novel computer-assisted diagnosis tools to provide rapid and cost-effective screening in places where massive traditional testing is not feasible. Lung ultrasound is a portable, easy to disinfect, low cost and non-invasive tool that can be used to identify lung diseases. Computer-assisted analysis of lung ultrasound imagery is a relatively recent approach that has shown great potential for diagnosing pulmonary conditions, being a viable alternative for screening and diagnosing COVID-19.ObjectiveTo evaluate and compare the performance of deep-learning techniques for detecting COVID-19 infections from lung ultrasound imagery.MethodsWe adapted different pre-trained deep learning architectures, including VGG19, InceptionV3, Xception, and ResNet50. We used the publicly available POCUS dataset comprising 3326 lung ultrasound frames of healthy, COVID-19, and pneumonia patients for training and fine-tuning. We conducted two experiments considering three classes (COVID-19, pneumonia, and healthy) and two classes (COVID-19 versus pneumonia and COVID-19 versus non-COVID-19) of predictive models. The obtained results were also compared with the POCOVID-net model. For performance evaluation, we calculated per-class classification metrics (Precision, Recall, and F1-score) and overall metrics (Accuracy, Balanced Accuracy, and Area Under the Receiver Operating Characteristic Curve). Lastly, we performed a statistical analysis of performance results using ANOVA and Friedman tests followed by post-hoc analysis using the Wilcoxon signed-rank test with the Holm’s step-down correction.ResultsInceptionV3 network achieved the best average accuracy (89.1%), balanced accuracy (89.3%), and area under the receiver operating curve (97.1%) for COVID-19 detection from bacterial pneumonia and healthy lung ultrasound data. The ANOVA and Friedman tests found statistically significant performance differences between models for accuracy, balanced accuracy and area under the receiver operating curve. Post-hoc analysis showed statistically significant differences between the performance obtained with the InceptionV3-based model and POCOVID-net, VGG19-, and ResNet50-based models. No statistically significant differences were found in the performance obtained with InceptionV3- and Xception-based models.ConclusionsDeep learning techniques for computer-assisted analysis of lung ultrasound imagery provide a promising avenue for COVID-19 screening and diagnosis. Particularly, we found that the InceptionV3 network provides the most promising predictive results from all AI-based techniques evaluated in this work. InceptionV3- and Xception-based models can be used to further develop a viable computer-assisted screening tool for COVID-19 based on ultrasound imagery.
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- 2021
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25. 5G/B5G Service Classification Using Supervised Learning
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Caridad E. Anias-Calderon, Joan D. Gonzalez-Franco, Juan I. Nieto-Hipolito, Jorge E. Preciado-Velasco, and Raul Rivera-Rodriguez
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Technology ,QH301-705.5 ,Computer science ,QC1-999 ,QoS ,Telecommunications service ,Machine learning ,computer.software_genre ,predictive model ,03 medical and health sciences ,Service-level agreement ,0502 economics and business ,General Materials Science ,Quality of experience ,Biology (General) ,QD1-999 ,Instrumentation ,KQI ,030304 developmental biology ,Fluid Flow and Transfer Processes ,Service (business) ,050210 logistics & transportation ,0303 health sciences ,business.industry ,Physics ,Process Chemistry and Technology ,Quality of service ,05 social sciences ,Supervised learning ,General Engineering ,Service provider ,Engineering (General). Civil engineering (General) ,ML ,Computer Science Applications ,Chemistry ,5G/B5G service classification ,QoE ,Performance indicator ,Artificial intelligence ,SLA ,TA1-2040 ,business ,computer ,KPI - Abstract
The classification of services in 5G/B5G (Beyond 5G) networks has become important for telecommunications service providers, who face the challenge of simultaneously offering a better Quality of Service (QoS) in their networks and a better Quality of Experience (QoE) to users. Service classification allows 5G service providers to accurately select the network slices for each service, thereby improving the QoS of the network and the QoE perceived by users, and ensuring compliance with the Service Level Agreement (SLA). Some projects have developed systems for classifying these services based on the Key Performance Indicators (KPIs) that characterize the different services. However, Key Quality Indicators (KQIs) are also significant in 5G networks, although these are generally not considered. We propose a service classifier that uses a Machine Learning (ML) approach based on Supervised Learning (SL) to improve classification and to support a better distribution of resources and traffic over 5G/B5G based networks. We carry out simulations of our proposed scheme using different SL algorithms, first with KPIs alone and then incorporating KQIs and show that the latter achieves better prediction, with an accuracy of 97% and a Matthews correlation coefficient of 96.6% with a Random Forest classifier.
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- 2021
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26. QoSComm: A Data Flow Allocation Strategy among SDN-Based Data Centers for IoT Big Data Analytics
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Juan I. Nieto-Hipolito, J. E. Lozano-Rizk, Mabel Vazquez-Briseno, María de los Ángeles Cosío-León, Juan C. Chimal-Eguia, and Raul Rivera-Rodriguez
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OpenFlow ,Computer science ,Big data ,QoS ,02 engineering and technology ,lcsh:Technology ,IoT big data analytics ,lcsh:Chemistry ,SDN ,0202 electrical engineering, electronic engineering, information engineering ,General Materials Science ,lcsh:QH301-705.5 ,Instrumentation ,Fluid Flow and Transfer Processes ,lcsh:T ,Data stream mining ,business.industry ,Process Chemistry and Technology ,Quality of service ,General Engineering ,020206 networking & telecommunications ,Telecommunications network ,lcsh:QC1-999 ,Computer Science Applications ,Data flow diagram ,lcsh:Biology (General) ,lcsh:QD1-999 ,lcsh:TA1-2040 ,020201 artificial intelligence & image processing ,Data center ,lcsh:Engineering (General). Civil engineering (General) ,Software-defined networking ,business ,lcsh:Physics ,Computer network - Abstract
When Internet of Things (IoT) big data analytics (BDA) require to transfer data streams among software defined network (SDN)-based distributed data centers, the data flow forwarding in the communication network is typically done by an SDN controller using a traditional shortest path algorithm or just considering bandwidth requirements by the applications. In BDA, this scheme could affect their performance resulting in a longer job completion time because additional metrics were not considered, such as end-to-end delay, jitter, and packet loss rate in the data transfer path. These metrics are quality of service (QoS) parameters in the communication network. This research proposes a solution called QoSComm, an SDN strategy to allocate QoS-based data flows for BDA running across distributed data centers to minimize their job completion time. QoSComm operates in two phases: (i) based on the current communication network conditions, it calculates the feasible paths for each data center using a multi-objective optimization method, (ii) it distributes the resultant paths among data centers configuring their openflow Switches (OFS) dynamically. Simulation results show that QoSComm can improve BDA job completion time by an average of 18%.
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- 2020
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27. A Discounted Cash Flow and Capital Budgeting Analysis of Silvopastoral Systems in the Amazonas Region of Peru
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Héctor V. Vásquez, Miguel S. Castillo, Raul Rivera, Wilmer Bernal, Rajan Parajuli, Erin O. Sills, Robert C. Abt, Stephanie Chizmar, Dante Pizarro, and Frederick W. Cubbage
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010504 meteorology & atmospheric sciences ,01 natural sciences ,Ecosystem services ,lcsh:Agriculture ,Capital budgeting ,silvopasture ,Agricultural science ,financial analysis ,Peru ,Financial analysis ,Hectare ,0105 earth and related environmental sciences ,Nature and Landscape Conservation ,Discounted cash flow ,Global and Planetary Change ,Ecology ,business.industry ,lcsh:S ,economics ,04 agricultural and veterinary sciences ,Livelihood ,040103 agronomy & agriculture ,0401 agriculture, forestry, and fisheries ,Livestock ,carbon payment ,Business ,Silvopasture - Abstract
Silvopasture is a type of agroforestry that could deliver ecosystem services and support local livelihoods by integrating trees into pasture-based livestock systems. This study modeled the financial returns from silvopastures, planted forests, and conventional cattle-pasture systems in Amazonas, Peru using capital budgeting techniques. Forests had a lower land expectation value (USD 845 per hectare) than conventional cattle systems (USD 1275 per hectare) at a 4% discount rate. &ldquo, Typical&rdquo, model silvopastures, based on prior landowner surveys in the Amazonas region, were most competitive at low discount rates. The four actual silvopastoral systems we visited and examined had higher returns (4%: USD 1588 to USD 9524 per hectare) than either alternative pure crop or tree system, more than likely through strategies for generating value-added such as on-site retail stands. Silvopasture also offers animal health and environmental benefits, and could receive governmental or market payments to encourage these practices.
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- 2020
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28. Orlando Tools: Development, Training, and Use of Scalable Applications in Heterogeneous Distributed Computing Environments
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Olga Basharina, Alexander G. Feoktistov, Sergei Gorsky, Andrei Tchernykh, Vassil Alexandrov, Raul Rivera-Rodriguez, Roman Kostromin, Ivan Sidorov, and Igor Bychkov
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Scheme (programming language) ,business.industry ,Computer science ,Distributed computing ,020207 software engineering ,Cloud computing ,02 engineering and technology ,Grid ,Training (civil) ,Domain (software engineering) ,Development (topology) ,Scalability ,0202 electrical engineering, electronic engineering, information engineering ,020201 artificial intelligence & image processing ,business ,computer ,computer.programming_language - Abstract
We address concepts and principles of the development, training, and use of applications in heterogeneous environments that integrate different computational infrastructures including HPC-clusters, grids, and clouds. Existing differences in the Grid and cloud computing models significantly complicate problem-solving processes in such environments for end-users. In this regards, we propose the toolkit named Orlando Tools for creating scalable applications for solving large-scale scientific and applied problems. It provides mechanisms for the subject domain specification, problem formulation, problem-solving time prediction, problem-solving scheme execution, monitoring, etc. The toolkit supports hands-on training skills for end-users. To demonstrate the practicability and benefits of Orlando Tools, we present an example of the development and use of the scalable application for solving practical problems of warehouse logistics.
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- 2019
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29. Software Defined Data Center for High Performance Computing Applications
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J. C. Chimal-Eguia, V. Rico-Rodriguez, Mabel Vazquez-Briseno, Raul Rivera-Rodriguez, Juan I. Nieto-Hipolito, J. E. Lozano-Rizk, María de los Ángeles Cosío-León, and E. Martinez-Martinez
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Computer science ,business.industry ,Distributed computing ,05 social sciences ,Software-defined data center ,050801 communication & media studies ,020206 networking & telecommunications ,02 engineering and technology ,Supercomputer ,0508 media and communications ,0202 electrical engineering, electronic engineering, information engineering ,Data center ,business ,Host (network) - Abstract
In recent years, traditional data centers have been used to host high-performance computing infrastructure, such as HPC clusters, addressing specific requirements for different research and scientific projects. Computes, storage, network, and security infrastructure is usually from heterogenous manufacturers and has multiple management interfaces.
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- 2019
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30. Monitoring Atrial Fibrillation using PPG Signals and a Smartphone
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Everardo Gutiérrez-López, Alejandro Estrella-Gallego, Mabel Vazquez Briseno, Juan I. Nieto-Hipolito, Armando Garcia-Berumen, Juan de Dios Sanchez-Lopez, and Raul Rivera-Rodriguez
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medicine.medical_specialty ,business.industry ,Computer applications to medicine. Medical informatics ,R858-859.7 ,General Engineering ,Life quality ,atrial fibrillation, photoplethysmogram ,Cardiac arrhythmia ,Atrial fibrillation ,smartphone ,sensors ,arrhythmia ,medicine.disease ,Ecg monitoring ,Quality of life ,Internal medicine ,Photoplethysmogram ,Cardiology ,Medicine ,In patient ,business ,Paroxysmal AF - Abstract
Atrial fibrillation (AF) is a common type of cardiac arrhythmia. AF is associated with increased rates of death and hospitalizations. It is also related to a degraded quality of life and reduced exercise capacity. Ageing increases the risk of developing AF, as well as hypertension and obesity. Continuous ECG monitoring is required in patients with previously diagnosed AF. Studies have also demonstrated that daily ECG monitoring increases the successful detection of silent AF among older adults. In this sense facilitating AF monitoring using portable devices such as Smartphones will increase patients life quality and could help to an early diagnosis. With this in mind in this work we present a proposal to detect AF using pulsatile photoplethysmogram (PPG) signal from a fingertip using the built-in camera lens in a smartphone. We developed an algorithm intended to sense paroxysmal AF considering resource utilization capabilities in order to be used in mobile devices with constrained.
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- 2020
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31. Use of Containers for High-Performance Computing
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S. Castañeda-Avila, F. Medrano-Jaimes, J. E. Lozano-Rizk, and Raul Rivera-Rodriguez
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business.industry ,Computer science ,05 social sciences ,050301 education ,Information technology ,020206 networking & telecommunications ,Hypervisor ,02 engineering and technology ,computer.software_genre ,Supercomputer ,System administrator ,Workflow ,Kernel (image processing) ,Virtual machine ,0202 electrical engineering, electronic engineering, information engineering ,Operating system ,DevOps ,business ,0503 education ,computer - Abstract
The past decade, virtual machines emerged to solve many infrastructure problems and practical use of computing resources. The limitations of this type of technology, are in the sense of resource overload because each virtual machine has a complete copy of an operating system plus different libraries needed to run an application. Containers technology reduces this load by eliminating the hypervisor and the virtual machine for its operation, where each application is executed with the most elementary of a server, plus a shared instance of the operating system that hosts it. Container technology is already an essential part of the IT industry, as it is a simpler and more efficient way to virtualize Micro-Services with workflow’s creations support in development and operations (DevOps). Unlike the use of virtual machines, this solution generates much less overhead in the kernel host and the application, improving performance. In the high-performance computing (HPC) there is a willingness to implement this solution for scientific computing purposes. The most important and standard technology in the industry is Docker, however is not a trivial and direct adoption of this standard for the requirements of scientific computing in a HPC environment. In the present study, a review of research works focused on the use of containers for the HPC will be carried out with the objective of familiarizing the user and system administrator of HPC in the use of this technology, and how scientific research projects can get benefit from this type of technology in terms of mobility of compute and reproducibility of workflows.
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- 2018
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32. Natural clays with an inherent uranium component that nevertheless sequester uranium from contaminated water
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Emilio S. Rivera, Tiffany Fowler, Antonio Lara, Young Ho Park, Raul Rivera, and Jeremy Jones
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inorganic chemicals ,Environmental Engineering ,chemistry.chemical_element ,010501 environmental sciences ,01 natural sciences ,complex mixtures ,Natural (archaeology) ,Article ,Cations ,Water Pollutants ,0105 earth and related environmental sciences ,Component (thermodynamics) ,010401 analytical chemistry ,Water Pollution ,Water ,Sorption ,Heavy metals ,General Medicine ,Uranium ,0104 chemical sciences ,Contaminated water ,chemistry ,Environmental chemistry ,Environmental science ,Clay - Abstract
Clays present a cost effective and sustainable method for removing uranium and heavy metals from drinking water because of their cation exchange capabilities. However, managing muddy suspensions is problematic; therefore, clay pellets as presented in this paper are a promising alternative. Three standard clays and two regional clays were evaluated for sorption, both in powder form and in pellet structure for comparison. The objective was to evaluate individual sorption processes and assess the effect on uranium sorption due to the process of altering the clay powder to produce pellets. The sorption capacity of the pellets is sufficiently large to not only sorb the intrinsic non-bonded uranium but to continue to sorb uranium from contaminated water. Furthermore, the uranyl cation was also removed preferentially in the presence of Pb(2+) and Cd(2+) heavy metal cations, hydronium ions, and more importantly the naturally occurring cations, Na(1+), Ca(2+), and Mg(2+) that occur in abundant concentrations. Clay pellets as well as powders reduced uranium concentrations, and in extreme cases from 450 ppb, 15 times the Environmental Protection Agency maximum contaminant level to non-detectable limits. Clay pellets are excellent candidates for the safe and manageable removal of uranium and heavy metals to produce potable water
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- 2018
33. Energy Consumption and Quality of Service Optimization in Containerized Cloud Computing
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Eduardo R. Concepción Morales, Arutyun Avetisyan, Andrei Tchernykh, Raul Rivera-Rodriguez, Jorge M. Cortés-Mendoza, Jose E Lozano Rizk, Rewer Canosa, Gleb Radchenko, and Zhihui Du
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Job shop scheduling ,business.industry ,Computer science ,Quality of service ,Distributed computing ,Cloud computing ,Energy consumption ,Virtualization ,computer.software_genre ,Scheduling (computing) ,Energy conservation ,Green computing ,business ,computer - Published
- 2018
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34. SAT0380 Panlar-accar recommendations on diagnosis and treatment of chikungunya-related inflammatory arthropathies in latin america
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Daniel Jaramillo-Arroyave, A.M. Sapag, John Londoño, Y. Fuentes, Raul Rivera, Maritza Quintero, F. Fernández-Castillo, R.A. Montúfar, Juan C. Rueda, M.C. Ruiz, P. Monge, H. Sandoval, P. Camilo, V. Khoury, Carlo V. Caballero-Uribe, J.L. Aguilar, C. Pineda, and I.Y. Moreno
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medicine.medical_specialty ,Latin Americans ,biology ,business.industry ,Mortality rate ,virus diseases ,Outbreak ,Aedes aegypti ,biology.organism_classification ,medicine.disease_cause ,Family medicine ,Health care ,Epidemiology ,Medicine ,Chikungunya ,business ,Medical literature - Abstract
Background Although mortality rates related with Chikungunya (CHIK) outbreaks into Latin America’s endemic-dengue rural and new urban regions are low, dealing with symptoms and sequelae can produce both a significant burden of disease and diminish quality of life — from many months to years — after the acute phase of infection, with a significant impact on public and individual health. Objectives The aim of this work was to establish a PANLAR-ACCAR consensus on diagnosis and treatment of CHIK-related inflammatory arthropathies transmitted by Ae. Aegypti and Ae. Albopictus in Latin America (LA). Methods Based on the Consensus Development Conference format, a panel of ACCAR rheumatologists (n=10) took part in this PANLAR initiative. Experts voted recommendations from a previous content analysis of the medical literature on CHIK, four subsequent topic’s Conferences and a workshop. Consensus represents the majority agreement (≥80%) achieved for each recommendation. Results The panel reach four overarching principles: 1) CHIK virus (CHIKV) is a re-emergent virus transmitted by two species of mosquitoes: Ae. Aegypti and Ae. Albopictus; 2) CHIKV caused massive outbreaks in LA; 3) Chronic CHIKV infection produces an inflammatory joint disease that in some cases can last several months to years, and 4) Currently, there are no vaccines or antivirals available for CHIKV infections. Conclusions PANLAR-ACCAR achieve 13 recommendations on CHIK categorised in three groups: 1) epidemiology and clinical manifestations; 2) diagnosis, and 3) treatment, representing the consensus agreement from the panel’s members. References [1] Pineda C, Munoz-Louis R, Caballero-Uribe CV, Viasus D. Chikungunya in the region of the Americas. A challenge for rheumatologists and health care systems. Clin Rheumatol2016;35(10):2381–5. [2] Fernandez-Salas I, Danis-Lozano R, Casas-Martinez M, Ulloa A, Bond JG, Marina CF, et al. Historical inability to control Aedes aegypti as a main contributor of fast dispersal of chikungunya outbreaks in Latin America. Antiviral Res2015;124:30–42. [3] Khoury VJ, Camilo PR. Chikungunya virus (CHIKV): what can be expected after the acute phase?Reumatol Clin2016;12(1):1–3. [4] JC Rueda, J-I Angarita, AM Santos, E-L Saldarriaga, I Pelaez-Ballestas, MJ Soares-Santeugini, J Londono. SAT0576 [5] Improved clinical scenario for chikungunya diagnosis Annals of the Rheumatic Diseases2017Jun;76(Suppl 2):994. Disclosure of Interest None declared
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- 2018
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35. Genetic tuning of fuzzy rule-based systems for multi-hop broadcast protocols for VANETs
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Javier Rubio-Loyola, Hiram Galeana-Zapién, Raul Rivera-Rodriguez, Salvador Villarreal-Reyes, and Alejandro Galaviz-Mosqueda
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Fuzzy rule ,Exploit ,Computer science ,Network packet ,business.industry ,Distributed computing ,ComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKS ,020206 networking & telecommunications ,02 engineering and technology ,Fuzzy logic ,0202 electrical engineering, electronic engineering, information engineering ,020201 artificial intelligence & image processing ,Fuzzy rule based systems ,Electrical and Electronic Engineering ,business ,Intelligent transportation system ,Computer communication networks ,Computer network - Abstract
Vehicular ad-hoc networks (VANETs) have been identified as a key technology to enable intelligent transport systems (ITS), which in turn have the potential to radically enhance the safety and comfort of vehicles on the road as well as the potential to reduce their environmental impact. Nevertheless, several issues still must be addressed in order to fully exploit the potential of VANETs in favor of ITSs. Particularly, one key open issue in VANETs is the multi-hop broadcast message dissemination (MBMD) for safety and infotainment applications. In this context, fuzzy rule-based systems (FRBSs) have been proved to be useful when designing MBMD protocols for VANETs. However, a methodological tuning of the FRBS for such MBMD protocols to improve their performance in terms of metrics like packet delivery ratio still remains open. This paper deals with the problem of determining the best position and overlap between fuzzy states (FSs) of the MFs for FRBS-based MBMD protocols in order to enhance its performance. Specifically, a component-based methodology using genetic algorithm (GA) for the MFs tuning problem is proposed. The proposed methodology is validated by tuning two relevant FRBS-based MBMD protocols found in the literature. The tuned MBMD protocols have been evaluated over a range of realistic scenarios. Obtained results from the evaluations show that the tuned MBMD protocols provide better performance than the heuristically defined FRBSs in terms of important metrics like packet delivery ratio.
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- 2015
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36. Distortion in the Eye Diagrams of Synchronous Non-synchronous and 90º Bend Discontinuities
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Eric Francisco Gutierrez Frias, Becerra Alvarez, Chavez Perez, Roberto Conte Galvan, Marco Antonio Gurrola Navarro, Francisco Jiménez Hernández, Oscar Blanco Alonso, Jose Luis Medina Monroy, Raul Rivera Rodriguez, Ricardo Arturo, Edwin Christian, and Alejandro Dueñas Jiménez
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Simulation algorithm ,Group (mathematics) ,Simple (abstract algebra) ,Distortion ,Electronic engineering ,Signal integrity ,Electrical and Electronic Engineering ,Ringing ,Classification of discontinuities ,Algorithm ,Mathematics - Abstract
A group of well-defined equations (1) are implemented on a simulation algorithm by using a 2-DFDTD method. The method allows find behaviors in the eye diagrams not encountered by simple physical measuring (2) (3).
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- 2015
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37. Investigation of HER-2 status, treatment response and survival analysis in cervical cancer patients
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Lucely Cetina, Catalina Trejo-Becerril, Delia Pérez-Montiel, Enrique Pérez-Cárdenas, Guadalupe Domínguez-Gómez, Alma Chavez-Blanco, Roberto Jiménez-Lima, Raul Rivera-Marquez, Judith Cruz-Velazquez, Lucia Taja-Chayeb, Norma Moreno-Soriano, and Alfonso Dueñas-González
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Oncology ,Cervical cancer ,medicine.medical_specialty ,Treatment response ,business.industry ,Internal medicine ,medicine ,Obstetrics and Gynecology ,business ,medicine.disease ,Survival analysis - Published
- 2020
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38. Sistema móvil de teleasistencia médica para la atención en tiempo real de casos de urgencia
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R. Tamayo-Fernández, A. Armenta-Ramade, Arturo Serrano-Santoyo, and Raul Rivera-Rodriguez
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emergencias médicas ,Telesalud ,comunicaciones ,videoconferencia SIP ,Ingeniería ,inalámbricas ,3G ,UML - Abstract
Este artículo describe un sistema móvil de teleasistencia médica para apoyar la atención de casos de emergencia, utilizando servicios de transmisión de signos vitales y videoconferencia en tiempo real. Así, en forma remota, los médicos especialistas pueden dar instrucciones precisas y oportunas a los paramédicos, con el propósito de mejorar la atención médica que recibe el paciente. Se analizan los aspectos técnicos de conectividad y factibilidad para la puesta en operación del sistema desde el punto de vista de cobertura inalámbrica, normatividad y tecnología actualmente disponibles en México, en donde los resultados obtenidos indican que la elección del servicio de comunicación inalámbrica es importante para soportar este servicio. Finalmente, se presentan resultados de la evaluación con diferentes tecnologías de comunicación inalámbrica y los retos e implicaciones en la adopción tecnológica por parte de los actores en la sala de emergencia y la unidad médica móvil, para que el sistema propuesto sea utilizado de manera efi ciente en el entorno hospitalario.
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- 2012
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39. Comparison of four mathematical models for braking of a motorcycle
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J. de Jesus Rubio, Raul Rivera, C. A. Hernandez, and Cesar Torres
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Engineering ,Software ,General Computer Science ,Mathematical model ,business.industry ,Relative velocity ,Control engineering ,Bicycle and motorcycle dynamics ,Numerical models ,Electrical and Electronic Engineering ,business ,Automotive engineering ,Data modeling - Abstract
The major contributions of this paper are as follows: 1) four mathematical models that are used to describe the motorcycle dynamics during braking are presented, the first three are obtained from previous papers and the fourth is proposed in this paper 2) the differences between the four mathematical models are described, 3) It is proven that the proposed mathematical model used to describe the motorcycle dynamics during braking is asymptotic astable, 4) a comparison between the four mathematical models is presented based in two facts: a) the relative velocity has to be positive during braking, and b) real data are obtained from a motorcycle and used in the comparisons.
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- 2011
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40. Validación de pruebas ELISA IgM anti-Toxoplasma para uso en programas de tamización en recién nacidos
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Elizabeth Torres, Jorge Enrique Gómez-Marín, Elkin Osorio, Maria Eugenia Castaño, Lilian Núñez, Raul Rivera, Maria Luisa Ramirez, and Leonor Chacon
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Microbiology (medical) ,IgM ,diagnosis ,business.industry ,screening ,specificity ,Western blot ,sensitivity ,Molecular biology ,tamización ,ROC curve ,recién nacidos ,Infectious Diseases ,newborn ,Recien nacido ,umbilical cord ,Medicine ,ELISA ,Pharmacology (medical) ,business ,Toxoplasmosis - Abstract
ResumenObjetivosEvaluar y determinar el punto de corte para la detección de IgM anti-Toxoplasma por el método ELISA, en muestras de sangre de cordón umbilical, mediante dos ensayos comerciales diferentes, y correlacionar los resultados obtenidos con el diagnóstico de toxoplasmosis congénita realizado por seguimiento serológico y los datos clínicos.MétodosSe evaluó la prueba IgM anti-Toxoplasma ELISA de Vircell®, frente a los resultados por Western blot e IgM ELISA de Labsystems®. Se estudiaron 105 muestras de cordón umbilical de niños colombianos, obtenidas de seis ciudades diferentes por Western blot y seguimiento clínico y serológico en aquellos positivos. Se obtuvo una curva receptor-operador (ROC) para la prueba ELISA IgM anti-Toxoplasma de Vircell® y de Labsystems ®. Se analizó la concordancia entre pruebas en 105 sueros obtenidos de cordón umbilicalResultadosEl mejor desempeño para la prueba Vircell® fue con un punto de corte de índice 8 y la prueba de Labsystems® con un punto de corte de 16 inmunounidades enzimáticas. Frente al Western blot, la prueba Vircell® tuvo una sensibilidad de 100 % (IC95%; 71,8-100) y una especificidad de 78 % (IC95%; 69-85,7), la prueba Labsystems® tuvo una sensibilidad de 100% (IC95%; 71,8-100) y una especificidad de 100 % (IC95%; 96-100). La concordancia entre ambas pruebas (Labsystems® y Vircell®) fue de 80 %, con un índice kappa de 0,45. Conclusiones. Un punto de corte de un índice 8 para la prueba ELISA IgM anti-Toxoplasma de Vircell® y un punto de corte de 16 inmunounidades enzimáticas por Labsystems®, permiten identificar infecciones congénitas en sangre de cordón umbilical en niños colombianos.AbstractObjectivesTo evaluate and validate the detection of anti-Toxoplasma IgM ELISA in umbilical cord blood by means of two different commercial assays and to correlate the results with the diagnosis of congenital infection in children by serological follow up and clinical data.Materials and methodsWe evaluated the commercial anti-Toxoplasma IgM ELISA kitÔ from Vircell (Granada, Spain) compared to the results of Toxoplasma IgM Western blotÔ (LDbio, Lyon, France) and IgM ELISA testÔ from Labsystems (Finland). We obtained the receptor-operator curve (ROC) for the IgM ELISA assay form Vircell and Labsystems. We studied 105 umbilical cord blood serum samples from Colombian children from six different cities by Western blot, and clinical and serological follow up for positive cases. The kappa agreement index was determined for the 105 sera obtained from umbilical cords.ResultsThe Vircell assay showed a better performance with a cut-off index of 8 against a 16 for Labsystems for enzyme immunounits (EUI). When the results were evaluated against the Western blot assay, the Vircell IgM assay had a sensitivity of 100% (IC95%: 71.8-100) and a specificity of 78% (IC95%: 69-85.7), the IgM assay from Labsystems had a sensitivity of 100% (IC95% 71.8-100) and a specificity of 100% (IC95% 96-100). Agreement between both tests (Labsystems and Vircell) was 80% and had a kappa index of 0.45.ConclusionsA cut-off point of 8 for the anti-Toxoplasma IgM ELISA assay from Vircell and 16 EIU for the Labsystems assay allow the identification of congenital infections in umbilical cord blood samples from Colombian children.
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- 2011
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41. Characterization of oral yeasts isolated from healthy individuals attended in different Colombian dental clinics
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Alejandra Zuluaga, Andrea Alejandra Villalba, Karen Arango, Eugenia Catalina Cepeda, Adiel Alberto Vasquez, Armando Roa, Martha Jhoana Arias, Adolfo Perez, Itzjak Kadar, Luis Fernando Casanova, Pedro Antonio Alfonso, Jorge Orlando Francisco Cuellar, Raul Rivera, Blanca Lynne Suarez, Beatriz L. Gómez, Ernesto González, Catalina de Bedout, Luis Fernando Montes, Luz Elena Cano, Lorena Pedraza, and Paola Andrea Pinillos
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Male ,Candida parapsilosis ,Rna 28s ,Mouth cavity ,Dna sequence ,02 engineering and technology ,01 natural sciences ,Pichia ,Microbial epidemiology ,Medicine ,Alcohol consumption ,Colonization ,Family history ,Middle aged ,Candida albicans ,Priority journal ,Candida dubliniensis ,biology ,Smoking ,General Medicine ,021001 nanoscience & nanotechnology ,Corpus albicans ,Colombian ,Body mass ,Medical history ,Female ,Microbiological examination ,Original Article ,Alcohol ,0210 nano-technology ,Adult ,Adolescent ,Nucleic acid base substitution ,Geotrichum candidum ,Oral yeast ,Rhodotorula mucilaginosa ,Oral hygiene ,Article ,General Biochemistry, Genetics and Molecular Biology ,Microbiology ,Candida species ,business.industry ,010401 analytical chemistry ,Mouth hygiene ,Nonhuman ,biology.organism_classification ,Yeast ,Social status ,0104 chemical sciences ,Tobacco use ,stomatognathic diseases ,Fungus isolation ,Dental clinic ,business ,Nucleotide sequence ,Body mass index ,Fungal colonization - Abstract
The aim of this study was to identify the most frequent yeasts in the oral cavity of adult individuals without immune disorders and to associate the presence of these oral yeasts with different characteristics of each individual. Oral rinse samples were obtained from 96 healthy adults and cultured in Sabouraud dextrose agar media and CHROMagar. Yeasts were identified by sequencing the D1/D2 region of the 28S rRNA gene. Probable association among the socio-demographic characteristics, body mass index, family and personal medical history, oral hygiene, tobacco and/or alcohol consumption habits and presence of oral fungi was analyzed. Contingency tables and logistic regression were employed to evaluate possible relationships between the presence of oral fungi and mixed colonization with these variables. 57.3% of the healthy individuals had oral yeasts and 21.8% had mixed colonization. The most prevalent yeasts were Candida albicans (52%), C. parapsilosis (17.9%), and C. dubliniensis (7.57%). Yeasts with most frequently mixed colonization were C. albicans and C. parapsilosis. No relationships were found among the variables analyzed. However, the presence of mixed colonization was related to the presence of dental prostheses (P less than 0.006), dental apparatuses (P=0.016) and O'Leary index (P=0.012). This is the first study that characterized oral yeasts in Colombian healthy individuals, determined the most prevalent oral yeasts C. albicans, C. parapsilosis and C. dublinensis and an association of mixed colonization with the use of dental prostheses and aparatology and poor hygiene. © 2019 by the Journal of Biomedical Research.
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- 2019
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42. Metaheuristic techniques comparison to optimize robotic end-effector behavior and its workspace
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Miguel Angel Funes Lora, Raul Rivera Blas, Manuel Faraón Carbajal Romero, Emmanuel Alejandro Merchán Cruz, and Edgar Alfredo Portilla-Flores
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0209 industrial biotechnology ,Computer science ,lcsh:Electronics ,lcsh:TK7800-8360 ,Control engineering ,02 engineering and technology ,Workspace ,Robot end effector ,lcsh:QA75.5-76.95 ,Computer Science Applications ,law.invention ,Computer Science::Robotics ,020901 industrial engineering & automation ,Artificial Intelligence ,law ,0202 electrical engineering, electronic engineering, information engineering ,020201 artificial intelligence & image processing ,lcsh:Electronic computers. Computer science ,Metaheuristic ,Software - Abstract
Many robots are dedicated to replicate trajectories recorded manually; the recorded trajectories may contain singularities, which occur when positions and/or orientations are not achievable by the robot. The optimization of those trajectories is a complex issue and classical optimization methods present a deficient performance when solving them. Metaheuristics are well-known methodologies for solving hard engineering problems. In this case, they are applied to obtain alternative trajectories that pass as closely as possible to the original one, reorienting the end-effector and displacing its position to avoid the singularities caused by limitations of inverse kinematics equations, the task, and the workspace. In this article, alternative solutions for an ill-posed problem concerning the behavior of the robotic end-effector position and orientation are proposed using metaheuristic algorithms such as cuckoo search, differential evolution, and modified artificial bee colony. The case study for this work considers a three-revolute robot (3R), whose trajectories can contain or not singularities, and an optimization problem is defined to minimize the objective function that represents the error of the alternative trajectories. A tournament in combination with a constant of proportionality allows the metaheuristics to modify the gradual orientation and position of the robot when a singularity is present. Consequently, the procedure selects from all the possible elbow-configurations the best that fits the trajectory. A classical numerical technique, Newton’s method, is used to compare the results of the applied metaheuristics, to evaluate their quality. The results of this implementation indicate that metaheuristic algorithms are an efficient tool to solve the problem of optimizing the end-effector behavior, because of the quality of the alternative trajectory produced.
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- 2018
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43. PHEFT: Pessimistic Image Processing Workflow Scheduling for DSP Clusters
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Victor E. Vladislavlev, Raul Rivera-Rodriguez, Andrei Tchernykh, Sergey V. Novikov, and Alexander Yu. Drozdov
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Numerical Analysis ,Multi-core processor ,Digital signal processor ,business.industry ,Computer science ,Distributed computing ,020206 networking & telecommunications ,Image processing ,02 engineering and technology ,DSP microprocessor ,multicore ,multiprocessors ,scheduling ,workflow ,resource management ,job allocation ,Theoretical Computer Science ,Scheduling (computing) ,Computational Mathematics ,Workflow ,Computational Theory and Mathematics ,0202 electrical engineering, electronic engineering, information engineering ,Cluster (physics) ,Workflow scheduling ,020201 artificial intelligence & image processing ,business ,Digital signal processing - Abstract
We address image processing workflow scheduling problems on a multicore digital signal processor cluster. We present an experimental study of scheduling strategies that include task labeling, prioritization, resource selection, and digital signal processor scheduling. We apply these strategies in the context of executing the Ligo and Montage applications. To provide effective guidance in choosing a good strategy, we present a joint analysis of three conflicting goals based on performance degradation. A case study is given, and experimental results demonstrate that a pessimistic scheduling approach provides the best optimization criteria trade-offs. The Pessimistic Heterogeneous Earliest Finish Time scheduling algorithm performs well in different scenarios with a variety of workloads and cluster configurations.
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- 2018
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44. Black Flower Coloration in Wild Lisianthius nigrescens: Its Chemistry and Ecological Consequences
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Raul Rivera, Peter G. Kevan, Kenneth R. Markham, Stephen J. Bloor, Melvin Shemluck, Charles Michener, and Rob Nicholson
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Gentianaceae ,Ultraviolet Rays ,Color ,Flowers ,Flavones ,General Biochemistry, Genetics and Molecular Biology ,chemistry.chemical_compound ,Pigment ,Dry weight ,Botany ,Glycosides ,Chromatography, High Pressure Liquid ,Ecosystem ,chemistry.chemical_classification ,biology ,Pigments, Biological ,biology.organism_classification ,Galactoside ,chemistry ,visual_art ,Anthocyanin ,Apigenin ,visual_art.visual_art_medium ,Pollen ,Luteolin - Abstract
The major pigments responsible for the flower color within the black flowered Gentianaceae, Lisianthius nigrescens, were characterized by HPLC and chemical analyses. HPLC analysis showed one major and one minor anthocyanin and 3 major and 3 minor flavone glycosides. The anthocyanins [delphinidin-3-O-rhamnol(1-6)galactoside and its 5-O-glucoside] comprised an extraordinary 24% of the dry weight of wild collected L. nigrescens corallas, and were accompanied in a 1:1 ratio by a range of apigenin and luteolin 8-C-glucosides and their 7-O-methyl ethers. The high levels of anthocyanins and flavones (and their copigmentation) is thought to account for the almost complete absorption of both UV and visible wavebands observed by reflectance photography.
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- 2004
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45. SEASONAL FEEDING AND COELOMIC FAT MASS IN THE WATERSNAKE NERODIA RHOMBIFER WERLERI IN VERACRUZ, MEXICO
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Kimberly A. Williams, Robert D. Aldridge, and Raul Rivera Teillery
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education.field_of_study ,Ecology ,media_common.quotation_subject ,Population ,Zoology ,Biology ,Age and sex ,Predation ,Fat mass ,Fat bodies ,Nerodia ,Coelom ,Animal Science and Zoology ,Reproduction ,education ,Ecology, Evolution, Behavior and Systematics ,media_common - Abstract
We describe the prey, seasonal patterns of feeding, and coelomic fat mass storage in a tropical population of the diamondback watersnake (Nerodia rhombifer werleri) and relate these data to the reproductive cycle of the studied population. Snakes were collected on the Papaloapan River, nearby lagoons, and as road kill near Tlacotalpan, Veracruz, Mexico in 1987. Diet and feeding frequency were determined by stomach content analysis of preserved snakes. The diet consisted primarily of fish (seven identified species belonging to six families). Of the adults examined, 21% of the 95 males and 32.5% of the 77 females contained food. In all age and sex classes of snakes, the feeding frequency did not differ between the wet and dry seasons. For adult males and adult females, coelomic fat mass was higher in February, March, and April than in other months. The variation in mass of the fat bodies was greater in adult females than in adult males. In females, low fat reserves may account for the low frequency of repro...
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- 2003
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46. Telemedicine Services over Rural Broadband Wireless Access Technologies: IEEE 802.22/WRAN and IEEE 802.16 WiMAX
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Salvador Villarreal-Reyes, Raul Rivera-Rodriguez, Roberto Conte-Galvan, Alejandro Galaviz-Mosqueda, and Roberto Magana-Rodriguez
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IEEE 802.11u ,IEEE 802 ,IEEE 802.11w-2009 ,business.industry ,Computer science ,Inter-Access Point Protocol ,ComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKS ,WiMAX ,IEEE 802.22 ,Wireless broadband ,IEEE 802.11e-2005 ,business ,Telecommunications ,Computer network - Abstract
Telemedicine services represent restrictive applications mostly related to patient’s consultation, diagnosis and monitoring through their biomedical signals by health specialists. Since wireless telemedicine services depend on technological infrastructure, rural area coverage has been considered an important challenge, and the Institute of Electrical and Electronics Engineers (IEEE) 802.16/WiMAX standard has been used to provide broadband wireless access (BWA) because of its MAC and PHY characteristics. However, the switch-off of the analog terrestrial network presents the opportunity of delivering high data rates over large coverage areas by means of TV white spaces (TVWS) technology using cognitive radio capabilities. Hence, at the end of 2011 the IEEE Working Group for Wireless Regional Area Networks (WRAN) released the first TVWS standard named 802.22. Within this standard bandwidth availability depends on the geographical location of the base station (BS) and the customer premise equipment (CPE).Therefore, a model to evaluate the suitability of IEEE 802.22 and WiMAX for the deployment of rural telemedicine networks is proposed. The model considers specific traffic profiles based on the telemedicine services that will be offered over the rural wireless telemedicine network. The evaluation presented in this chapter is performed by calculating the number of telemedicine services that IEEE 802.22/WRAN and IEEE 802.16/WiMAX networks can support considering the available bandwidth and the telemedicine traffic profiles requirements. Frame preambles and a MAC/PHY overhead factor per active connection are considered within the analysis. A case study from the State of Chiapas, Mexico, is presented for the deployment of wireless rural telemedicine networks based on the IEEE 802.16/WiMAX and IEEE 802.22/WRAN standards.
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- 2015
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47. Multi-hop broadcast message dissemination in vehicular ad hoc networks: A security perspective review
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Salvador Villarreal-Reyes, Alejandro Galaviz-Mosqueda, Miguel Morales-Sandoval, Miguel A. Alonso-Arévalo, Hiram Galeana-Zapién, and Raul Rivera-Rodriguez
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Computer Networks and Communications ,Computer science ,Wireless ad hoc network ,ComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKS ,General Engineering ,020302 automobile design & engineering ,020206 networking & telecommunications ,02 engineering and technology ,Computer security ,computer.software_genre ,lcsh:QA75.5-76.95 ,Hop (networking) ,0203 mechanical engineering ,0202 electrical engineering, electronic engineering, information engineering ,lcsh:Electronic computers. Computer science ,computer ,Dissemination - Abstract
Vehicular ad hoc networks have been identified as a key technology for enabling safety and infotainment applications in the context of smart and connected vehicles. In this sense, diverse approaches of multi-hop broadcast protocols have been proposed to collect and disseminate context information through the network. However, before vehicular ad hoc networks applications fulfill their expected potential to connect smart vehicles, several issues must be addressed. Among these issues, those related to security are of particular importance. In this article, the main security issues of broadcast message dissemination in vehicular ad hoc networks are discussed. Moreover, a review of the most relevant threats and proposed solutions to secure broadcast message dissemination in vehicular ad hoc networks is presented and discussed. As mentioned, security is an important topic which has not been fully addressed in vehicular ad hoc networks; therefore, the aim of this article is to introduce security issues and proposed solutions related to three main security concerns associated with the message dissemination process in vehicular ad hoc networks: network access, data consistency, and broadcast protocols.
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- 2017
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48. Aplicación del ciclo de vida y el análisis estructurado en el desarrollo de un laboratorio virtual de transformadores monofásicos
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Segio Raul Rivera-Rodríguez and John Milton Ramírez-Romero
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General Materials Science - Abstract
El desarrollo de Laboratorios Virtuales es un campo especial dentro del desarrollo de software debido a las relaciones interdisciplinares que surgen y las características de proyectos de esa naturaleza. En el primer semestre de 2016 se desarrolló, en la Universidad Nacional de Colombia, un Trabajo de Grado titulado Desarrollo de un laboratorio virtual computarizado de un transformador monofásico para el laboratorio de conversión electromagnética dentro del proyecto de investigación formulado: estudio del impacto de la estrategia pedagógica llamada "virtual labs" en el desarrollo de los cursos de laboratorio de máquinas eléctricas e implementación de laboratorio virtual computarizado de transformadores de potencia para la Universidad Nacional de Colombia sede Bogotá. Para hacer realidad el desarrollo del laboratorio virtual, fue necesario integrar temáticas de Pedagogía, Ingeniería de Sistemas e Ingeniería Eléctrica. En este artículo se busca que los lectores que estén interesados en el desarrollo de un Laboratorio Virtual conozcan las directrices básicas necesarias para realizar las etapas iniciales: la fase de análisis y la fase de diseño. Estas fases son críticas ya que describen el sistema actual y definen las características del Laboratorio Virtual, es tal la importancia de estas fases que, de hacerse de forma errónea, conducirá al fracaso del proyecto.
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- 2017
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49. Evaluation of IgG anti-toxoplasma avidity and polymerase chain reaction in the postnatal diagnosis of congenital toxoplasmosis
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Nestor Cardona, Fabiana Lora, Victor Sanchez, Elizabeth Torres, Jorge Enrique Gómez-Marín, and Raul Rivera
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Microbiology (medical) ,Immunoassay ,Male ,business.industry ,Antibody Affinity ,Infant, Newborn ,Antibodies, Protozoan ,Infant ,Polymerase Chain Reaction ,Sensitivity and Specificity ,Congenital toxoplasmosis ,Toxoplasmosis, Congenital ,law.invention ,Infectious Diseases ,law ,Immunoglobulin G ,Pediatrics, Perinatology and Child Health ,Immunology ,Medicine ,Humans ,Avidity ,Female ,business ,Toxoplasma ,Polymerase chain reaction - Abstract
Confirmatory tests for congenital toxoplasmosis were evaluated in 23 infected and 31 uninfected newborns. Conventional polymerase chain reaction was better than real-time polymerase chain reaction, but did not identify additional cases. Avidity tests added 2 new cases that were not identified by other criteria. Overall sensitivity was 82.6%. Avidity assay, but not polymerase chain reaction, increased the sensitivity of confirmatory assays in congenital toxoplasmosis.
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- 2013
50. Cross-Layer Design for Videoconferencing Applications in WiMAX 802.16e Networks
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Raul Rivera, Eduardo Patron, Arturo Serrano, and Oscar Olivares
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business.industry ,Computer science ,Network packet ,ComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKS ,Teleconference ,computer.software_genre ,WiMAX ,Videoconferencing ,Transmission (telecommunications) ,Broadband ,Wireless ,Mobile telephony ,business ,Telecommunications ,computer ,Computer network - Abstract
Transmission of real time videoconference sessions using wireless technologies presents important challenges. Channel impairments have a great effect in the quality of the video signal even in cases where emerging broadband technologies such as WiMax are used. This paper describes a proposal based on Cross-Layer-Design for reducing the data packet losses and its impact in the perceived quality of the received signal.
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- 2010
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