17 results on '"Omar Villa"'
Search Results
2. Spatio-temporal variation of reference evapotranspiration from empirical methods in Chihuahua, Mexico
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Augusto Omar Villa-Camacho, Laura Maleni Ordoñez-Hernández, José Antonio Quevedo-Tiznado, Osias Ruiz-Alvarez, Ronald Ernesto Ontiveros-Capurata, and Alberto Gonzalez-Sanchez
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Empirical research ,Mean squared error ,Homogeneous ,Evapotranspiration ,Climatology ,Environmental science ,Estimation methods ,Arid ,Field (geography) ,Multivariate interpolation - Abstract
Introduction: Evapotranspiration is key in the management of arid agricultural areas. In Chihuahua, the volume of irrigation water is based on reference evapotranspiration (ETo) calculated with empirical methods and extrapolated to the cropped area, which is inaccurate. The alternative is to calculate ETo variation by spatial interpolation. Objective: To analyze the spatio-temporal variation of ETo using empirical methods and spatial interpolation in Chihuahua, Mexico. Methodology: Records from 33 meteorological stations from 1960-2013 and seven ETo estimation methods were used. The results were compared with the Penman-Monteith method, modified by FAO (PMMF), ANOVA analysis (P ≤ 0.05), and homogeneous ETo surfaces built from the point values by spatial interpolation. Results: The Hargreaves method (R2 = 0.91, RMSE = 1.16 and ME = -0.69 mm-day-1) had a smaller bias with respect to PMMF. ETo values ranged from 2.5 to 7.1 mm-day-1 in a west-east direction, with maximum values at low elevations and minimum values at high elevations, which showed the influence of the Sierra Madre Occidental on ETo. This characteristic was most noticeable in the warm months (June to September). Limitations of the study: The use of estimated data needs field validation. Originality: The ETo estimation with seven empirical methods and one spatial interpolation method to extrapolate values to areas with scarce meteorological data. Conclusions: The Hargreaves method allows estimating the spatio-temporal variation of ETo in large extensions and areas with limited meteorological information. more...
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- 2021
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Catalog
3. Student-created videos in online STEM education: a large, interdisciplinary, randomized control study
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Alvina Atkinson, Patrice Bell, Indhira De La Rosa, Tonya DeGeorge, Lorraine Jonassen, Vinavtee Kokil, Seungjin Lee, Mia Malloy, Katherine Pinzon, Cindy Robertson, Jamye Curry Savage, Rabia Shahbaz, Omar Villanueva, Joshua Wludyga, and Joshua Morris more...
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Student-created videos ,Problem-solving ,Online courses ,STEM education ,Active learning ,Student engagement ,Education - Abstract
Abstract Student-created videos engage students’ interests, creativity, and content knowledge and enrich collaborative learning in STEM education. These videos enhance critical thinking and analytical skills, which are essential tools in the fields of science, technology, engineering, and mathematics (STEM). This study presents the results of such an assignment across several STEM areas (biology, chemistry, exercise science, information technology, and mathematics) at a minority-serving, liberal arts higher education institution in the southeast region of the United States. Undergraduate students (n = 557) across varied, online course modalities (synchronous and asynchronous) were required to create four problem-solving videos 3–8 min in duration. Assessment tools included a self-assessment of learning gains survey given to control and experimental groups and a post-video creation survey given only to experimental groups. Grade data was also collected from all sections. Comparing the experimental and control groups, students showed a statistically significant gain in their ability to give oral presentations, create videos, and edit videos. Qualitative data from free-response questions corroborate these gains and suggest that students also grew in content knowledge and conceptual understanding through these assignments. Our study implements a multimedia theoretical framework which suggests students learn more effectively from consuming presentations with both auditory and visual components. Our results suggest students see similar gains from producing presentations with both auditory and visual components. Further our results suggest that multimedia production enhances students’ presentation skills. From a practical perspective, this study suggests that faculty should incorporate student-created videos in online classes, which typically require oral presentations in person. Faculty are also advised to require oral and visual components within these videos to maximize learning gains from the perspective of a multimedia theoretical framework. more...
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- 2024
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4. Overexpression of ameloblastin in secretory ameloblasts results in demarcated, hypomineralized opacities in enamel
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Yong-Hee Patricia Chun, Chunyan Tan, Omar Villanueva, Madeline E. Colley, Travis J. Quintanilla, Mohamed S. Basiouny, Caldonia A. Hartel, Cameron S. Critchfield, Stephan B. H. Bach, Roberto J. Fajardo, and Cong-Dat Pham more...
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molar–incisor hypomineralization ,enamel hypomineralization ,enamel demarcation ,enamel formation ,mineralization ,ameloblastin (Ambn) ,Physiology ,QP1-981 - Abstract
Introduction: Developmental defects of the enamel manifest before tooth eruption and include amelogenesis imperfecta, a rare disease of underlying gene mutations, and molar–incisor hypomineralization (MIH), a prevalent disease in children originating from environmental and epigenetic factors. MIH enamel presents as the abnormal enamel marked by loss of translucency, demarcation between the healthy and affected enamel, and reduced mineral content. The pathophysiology of opaque, demarcated enamel lesions is not understood; however, the retention of enamel proteins in the matrix has been suggested. Ameloblastin (Ambn) is an enamel protein of the secreted calcium-binding phosphoproteins (SCPPs) critical for enamel formation. When the Ambn gene is mutated or deleted, teeth are affected by hypoplastic amelogenesis imperfecta.Methods: In this study, enamel formation in mice was analyzed when transgenic Ambn was overexpressed from the amelogenin promoter encoding full-length Ambn. Ambn was under- and overexpressed at six increasing concentrations in separate mouse lines.Results: Mice overexpressing Ambn displayed opaque enamel at low concentrations and demarcated lesions at high concentrations. The severity of enamel lesions increased starting from the inner enamel close to the dentino-enamel junction (DEJ) to span the entire width of the enamel layer in demarcated areas. Associated with the opaque enamel were 17-kDa Ambn cleavage products, a prolonged secretory stage, and a thin basement membrane in the maturation stage. Ambn accumulations found in the innermost enamel close to the DEJ and the mineralization front correlated with reduced mineral content. Demarcated enamel lesions were associated with Ambn species of 17 kDa and higher, prolonged secretory and transition stages, a thin basement membrane, and shortened maturation stages. Hypomineralized opacities were delineated against the surrounding mineralized enamel and adjacent to ameloblasts detached from the enamel surface. Inefficient Ambn cleavage, loss of contact between ameloblasts, and the altered basement membrane curtailed the endocytic activity; thus, enamel proteins remained unresorbed in the matrix. Ameloblasts have the ability to distinguish between Ambn concentration and Ambn cleavage products through finely tuned feedback mechanisms. The under- or overexpression of Ambn in murine secretory ameloblasts results in either hypoplastic amelogenesis imperfecta or hypomineralization with opaque or sharply demarcated boundaries of lesions, similar to MIH. more...
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- 2024
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5. Spatio-temporal variation of reference evapotranspiration from empirical methods in Chihuahua, Mexico.
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Omar Villa-Camacho, Augusto, Ernesto Ontiveros-Capurata, Ronald, Ruíz-Álvarez, Osías, González-Sánchez, Alberto, Antonio Quevedo-Tiznado, José, and Maleni Ordoñez-Hernández, Laura
- Abstract
Copyright of Ingeniería Agrícola y Biosistemas is the property of Universidad Autonoma Chapingo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) more...
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- 2021
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6. System Dynamics and KPI’s Definition in the Automotive Sector
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Nevarez, Omar Villa, primary, Molina, Maria Guadalupe Lopez, additional, and Gamino, Juan Alfredo Lino, additional
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- 2017
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7. System Dynamics and KPI’s Definition in the Automotive Sector
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Maria Guadalupe Lopez Molina, Omar Villa Nevarez, and Juan Alfredo Lino Gamiño
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Balanced scorecard ,Process management ,business.industry ,05 social sciences ,Control (management) ,Automotive industry ,Original equipment manufacturer ,System dynamics ,Competition (economics) ,03 medical and health sciences ,0302 clinical medicine ,0502 economics and business ,Business ,Marketing ,050203 business & management ,030217 neurology & neurosurgery - Abstract
In Mexico, the Automotive Industry is one of the most important sectors, based on the amount of sales, as well as for the number of people employed. The level of competition facing firms to win OEM programs requires having a very strict control over the whole company’s operation. System Dynamics is presented as a very powerful methodology for modeling the current and future situation of a company and combined with the Balanced scorecard concept, both provide a deep insight into the dynamics of the company. Based on this case of study a new methodology is proposed which provides a deeper insight on how the system works in such a way that the development of the company’s strategy has greater impact. Through the simulation of 24 months into the future it is possible to understand the system´s behavior in terms of the interrelation of the most critical variables which were defined as the main KPI´s. more...
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- 2017
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8. Use of polypill to improve therapeutic adherence and outcomes in adults with recent acute myocardial infarction: is it an effective strategy?
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Yelson Alejandro Picón-Jaimes, María Margarita Garcés-Lince, Juan Fernando Gómez-Gómez, and Omar Villamizar-Rueda
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adherence ,medication ,treatment ,outcome ,myocardial infarction ,Medicine (General) ,R5-920 - Published
- 2022
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9. BMHP1-derived self-assembling peptides: hierarchically assembled structures with self-healing propensity and potential for tissue engineering applications
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Ki Tae Nam, Omar Villa, Ronald N. Zuckermann, Antonino Natalello, Francesca Taraballi, Angelo L. Vescovi, Diego Silva, Silvia Maria Doglia, Andrea Caprini, Fabrizio Gelain, Gelain, F, Silva, D, Caprini, A, Taraballi, F, Natalello, A, Villa, O, Nam, K, Zuckermann, R, Doglia, S, and Vescovi, A more...
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Scaffold ,Nanostructure ,Cellular differentiation ,General Physics and Astronomy ,Nanotechnology ,Regenerative medicine ,Neural Stem Cells ,Tissue engineering ,Humans ,General Materials Science ,Nerve Growth Factors ,Cells, Cultured ,Cell Proliferation ,Neurons ,Self-assembling peptides ,Tissue Engineering ,Chemistry ,General Engineering ,BIO/13 - BIOLOGIA APPLICATA ,Cell Differentiation ,BIO/10 - BIOCHIMICA ,FIS/01 - FISICA SPERIMENTALE ,Cell culture ,Biotinylation ,Biophysics ,Feasibility Studies ,Self-assembling peptide - Abstract
Self-assembling peptides (SAPs) are rapidly gaining interest as bioinspired scaffolds for cell culture and regenerative medicine applications. Bone Marrow Homing Peptide 1 (BMHP1) functional motif (PFSSTKT) was previously demonstrated to stimulate neural stem cell (NSC) viability and differentiation when linked to SAPs. We here describe a novel ensemble of SAPs, developed from the BMHP1 (BMHP1-SAPs), that spontaneously assemble into tabular fibers, twisted ribbons, tubes and hierarchical self-assembled sheets: organized structures in the nano- and microscale. Thirty-two sequences were designed and evaluated, including biotinylated and unbiotinylated sequences, as well as a hybrid peptide-peptoid sequence. Via X-ray diffraction (XRD), CD, and FTIR experiments we demonstrated that all of the BMHP1-SAPs share similarly organized secondary structures, that is, β-sheets and β-turns, despite their heterogeneous nanostructure morphology, scaffold stiffness, and effect over NSC differentiation and survival. Notably, we demonstrated the self-healing propensity of most of the tested BMHP1-SAPs, enlarging the set of potential applications of these novel SAPs. In in vitro cell culture experiments, we showed that some of these 10-mer peptides foster adhesion, differentiation, and proliferation of human NSCs. RGD-functionalized and hybrid peptide-peptoid self-assembling sequences also opened the door to BMHP1-SAP functionalization with further bioactive motifs, essential to tailor new scaffolds for specific applications. In in vivo experiments we verified a negligible reaction of the host nervous tissue to the injected and assembled BMHP1-SAP. This work will pave the way to the development of novel SAP sequences that may be useful for material science and regenerative medicine applications. more...
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- 2011
10. Glycine-spacers influence functional motifs exposure and self-assembling propensity of functionalized substrates tailored for neural stem cell cultures
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Francesca Taraballi, Silvia Maria Doglia, Antonino Natalello, Marcello Campione, Omar Villa, Fabrizio Gelain, Alberto Paleari, Taraballi, F, Natalello, A, Campione, M, Villa, O, Doglia, S, Paleari, A, and Gelain, F more...
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biomaterial, nanostructure, neural stem cell, AFM, FTIR, Micro-Raman ,Scaffold ,nanostructure ,biomaterial ,Biomedical Engineering ,Biophysics ,Neuroscience (miscellaneous) ,Biomaterial ,Biology ,Bioinformatics ,Regenerative medicine ,In vitro ,Neural stem cell ,Neural tissue engineering ,neural stem cell ,Micro-Raman ,FTIR ,Tissue engineering ,Surface modification ,AFM ,Original Research ,Neuroscience - Abstract
The understanding of phenomena involved in the self-assembling of bio-inspired biomaterials acting as three-dimensional scaffolds for regenerative medicine applications is a necessary step to develop effective therapies in neural tissue engineering. We investigated the self-assembled nanostructures of functionalized peptides featuring four, two or no glycine-spacers between the self-assembly sequence RADA16-I and the functional biological motif PFSSTKT. The effectiveness of their biological functionalization was assessed via in vitro experiments with neural stem cells (NSCs) and their molecular assembly was elucidated via atomic force microscopy, Raman and Fourier Transform Infrared spectroscopy. We demonstrated that glycine-spacers play a crucial role in the scaffold stability and in the exposure of the functional motifs. In particular, a glycine-spacer of four residues leads to a more stable nanostructure and to an improved exposure of the functional motif. Accordingly, the longer spacer of glycines, the more effective is the functional motif in both eliciting NSCs adhesion, improving their viability and increasing their differentiation. Therefore, optimized designing strategies of functionalized biomaterials may open, in the near future, new therapies in tissue engineering and regenerative medicine. more...
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- 2010
11. SUSHI Implementation: The Client Side Experience
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Omar Villa
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business.industry ,Computer science ,Internet privacy ,Client-side ,business - Published
- 2011
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12. Evaluation of the Adverse Effects of Chronic Exposure to Donepezil (An Acetylcholinesterase Inhibitor) in Adult Zebrafish by Behavioral and Biochemical Assessments
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Gilbert Audira, Nguyen Thi Ngoc Anh, Bui Thi Ngoc Hieu, Nemi Malhotra, Petrus Siregar, Omar Villalobos, Oliver B. Villaflores, Tzong-Rong Ger, Jong-Chin Huang, Kelvin H.-C. Chen, and Chung-Der Hsiao
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donepezil ,acetylcholinesterase inhibitor ,dementia ,zebrafish ,behavior ,Microbiology ,QR1-502 - Abstract
Donepezil (DPZ) is an acetylcholinesterase inhibitor used for the clinical treatment of mild cognitive impairment. However, DPZ has been reported to have adverse effects, including causing abnormal cardiac rhythm, insomnia, vomiting, and muscle cramps. However, the existence of these effects in subjects without Dementia is unknown. In this study, we use zebrafish to conduct a deeper analysis of the potential adverse effects of DPZ on the short-term memory and behaviors of normal zebrafish by performing multiple behavioral and biochemical assays. Adult zebrafish were exposed to 1 ppm and 2.5 ppm of DPZ. From the results, DPZ caused a slight improvement in the short-term memory of zebrafish and induced significant elevation in aggressiveness, while the novel tank and shoaling tests revealed anxiolytic-like behavior to be caused by DPZ. Furthermore, zebrafish circadian locomotor activity displayed a higher reduction of locomotion and abnormal movement orientation in both low- and high-dose groups, compared to the control group. Biomarker assays revealed that these alterations were associated with an elevation of oxytocin and a reduction of cortisol levels in the brain. Moreover, the significant increases in reactive oxygen species (ROS) and malondialdehyde (MDA) levels in muscle tissue suggest DPZ exposure induced muscle tissue oxidative stress and muscle weakness, which may underlie the locomotor activity impairment. In conclusion, we show, for the first time, that chronic waterborne exposure to DPZ can severely induce adverse effects on normal zebrafish in a dose-dependent manner. These unexpected adverse effects on behavioral alteration should be carefully addressed in future studies considering DPZ conducted on zebrafish or other animals. more...
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- 2020
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13. UVB Irradiation Induced Cell Damage and Early Onset of Junbb Expression in Zebrafish
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Rui-Yi Chen, Chun-Ju Lin, Sung-Tzu Liang, Omar Villalobos, Oliver B. Villaflores, Bao Lou, Yu-Heng Lai, and Chung-Der Hsiao
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UVB ,zebrafish ,skin ,biomarker ,microarray ,Veterinary medicine ,SF600-1100 ,Zoology ,QL1-991 - Abstract
Ultraviolet B (UVB) radiation has drawn more attention over these past few decades since it causes severe DNA damage and induces inflammatory response. Serial gene profiling and high throughput data in UVB-associated phenomenon in human cultured cells or full rack of human skin have been investigated. However, results using different tissue models lead to ambiguity in UVB-induced pathways. In order to systematically understand the UVB-associated reactions, the zebrafish model was used, and whole organism gene profiling was performed to identify a novel biomarker which can be used to generate a new mechanistic approach for further screening on a UVB-related system biology. In this study, detailed morphological assays were performed to address biological response after receiving UVB irradiation at morphological, cellular, and molecular levels. Microarray screening and whole genome profiling revealed that there is an early onset expression of junbb in zebrafish embryos after UVB irradiation. Also, the identified novel biomarker junbb is more sensitive to UVB response than mmps which have been used in mouse models. Moreover, cellular and molecular response chronology after UVB irradiation in zebrafish provide a solid and fundamental mechanism for use in a UV radiation-associated study in the future. more...
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- 2020
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14. Influencia de factores no genéticos en el intervalo entre partos de búfalas de río
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Ángel Ceró Rizo, Guillermo Guevara Viera, Luis Maza Luis, and Omar Villavicencio Reyes
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búfalo de río ,intervalo parto-parto ,factores no genéticos ,Animal culture ,SF1-1100 - Abstract
El trabajo es una evaluación de la influencia de los factores no genéticos en el intervalo entre partos de búfalas de río, mediante los registros de 740 partos de 210 animales, pertenecientes a la Empresa Genética Maraguán, provincia de Camagüey, Cuba. A las variables sexo de la cría, rebaño, número de partos, época y el año del parto se les aplicó análisis de varianza múltiple. El paquete estadístico utilizado fue el SPSS. Los factores no genéticos ejercieron una influencia significativa (P < 0,01) sobre el intervalo entre partos, el cual alcanzó una media de 389,2 ± 6,3 días. La tendencia del intervalo entre partos para 2007 y 2010 es negativa. more...
- Published
- 2013
15. 3D culture of adult mouse neural stem cells within functionalized self-assembling peptide scaffolds
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Carla Cunha, Omar Villa, Silvia Panseri, Diego Silva, and Fabrizio Gelain
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Male ,Medicine (General) ,Materials science ,Biophysics ,Pharmaceutical Science ,Bioengineering ,Nanotechnology ,02 engineering and technology ,Biomaterials ,Mice ,03 medical and health sciences ,3D cell culture ,R5-920 ,Neural Stem Cells ,Tissue engineering ,International Journal of Nanomedicine ,Drug Discovery ,Animals ,Neural cell ,Cell Proliferation ,Original Research ,030304 developmental biology ,Analysis of Variance ,0303 health sciences ,Matrigel ,Tissue Scaffolds ,Viscosity ,Organic Chemistry ,Cell Differentiation ,Hydrogels ,General Medicine ,021001 nanoscience & nanotechnology ,Neural stem cell ,Nanostructures ,Cell biology ,Mice, Inbred C57BL ,Nanomedicine ,3D in vitro model ,Cell culture ,tissue engineering ,Neural tissue regeneration ,Microscopy, Electron, Scanning ,Peptides ,0210 nano-technology ,Oligopeptides ,Self-assembling peptide - Abstract
Carla Cunha1,2, Silvia Panseri3,4, Omar Villa1,2, Diego Silva1,2, Fabrizio Gelain1,21Department of Biotechnology and Biosciences, University of Milano-Bicocca; 2Center for Nanomedicine and Tissue Engineering, CNTE – A.O. Ospedale Niguarda Ca' Granda, Milan; 3Laboratory of Biomechanics and Technology Innovation, Rizzoli Orthopaedic Institute, Bologna; 4Laboratory of Nano-Biomagnetism, Institute of Science and Technology for Ceramics, National Research Council, Faenza, ItalyAbstract: Three-dimensional (3D) in vitro models of cell culture aim to fill the gap between the standard two-dimensional cell studies and the in vivo environment. Especially for neural tissue regeneration approaches where there is little regenerative capacity, these models are important for mimicking the extracellular matrix in providing support, allowing the natural flow of oxygen, nutrients, and growth factors, and possibly favoring neural cell regrowth. We have previously demonstrated that a new self-assembling nanostructured biomaterial, based on matrigel, was able to support adult neural stem cell (NSC) culture. In this study, we developed a new 3D cell culture system that takes advantage of the nano- and microfiber assembling process, under physiologic conditions, of these biomaterials. The assembled scaffold forms an intricate and biologically active matrix that displays specifically designed functional motifs: RGD (Arg-Gly-Asp), BMHP1 (bone marrow homing peptide 1), and BMHP2, for the culture of adult NSCs. These scaffolds were prepared at different concentrations, and microscopic examination of the cell-embedded scaffolds showed that NSCs are viable and they proliferate and differentiate within the nanostructured environment of the scaffold. Such a model has the potential to be tailored to develop ad hoc designed peptides for specific cell lines.Keywords: biomaterials, tissue engineering, 3D in vitro model more...
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16. Joven mujer con mioclonías, pérdida de sensibilidad, hemiparesia derecha y convulsiones tras dos episodios consecutivos de herpes zoster.
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Renzo Arauco Brown, Meylin Aphang Lam, Omar Villanueva Muñoz, Úrsula Rodríguez Frías, and Daniel Cáceres Alpaca
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Medicine - Published
- 2007
17. ANÁLISIS PARA LA CORRECCIÓN DE ERRORES EN LA SEÑAL GPS
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Fausto Ernesto Orozco Iguasnia, René Omar Villa López, Liliana Guzmán, and Wilson Gustavo Chango
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General Works - Abstract
El objetivo de esta investigación fue desarrollar el algoritmo de filtro de Kalman en Matlab y su posterior evaluación en la señal GPS para determinar las mejoras que se obtiene ante los diferentes tipos de errores q afecta a la señal en transmisión y recepción. Esta técnica permitió eliminar los diferentes tipos de errores producidos por el ruido térmico, multipath, la refracción entre otros, que afectan principalmente a receptores que trabajan en simple frecuencia. Para realizar la diferenciación se usó los archivos Rinex de los receptores ubicados en tierra, para lo cual se extrajo las medidas de pseudo-rango y la fase de portadora es un tiempo estimado, generando la señal código menos fase denominado (CMC) para luego ser filtrada permitiendo obtener la señal CMC-Suavizada. Para el análisis de datos se aplicó estadística descriptica, la misma que permitió identificar mediante gráficas las señales originales y corregidas por el algoritmo en varios. Como conclusión se determinó que los valores del tiempo de estabilidad del filtro de Kalman están en un rango de 300 a 1800 segundos permitiendo observar la disminución del error en la señal, es así que entre más grande sea el tiempo estimado se produce una mejora en la reducción de los errores de manera gradual con respecto a la señal original. PALABRAS CLAVE: Telecomunicaciones; sistema de posicionamiento global; archivos rinex; filtro de Kalman; error ionosférico; Matlab ANALYSIS FOR CORRECTION OF ERRORS IN THE GPS SIGNAL ABSTRACT The objective of this investigation was to develop the Kalman filter algorithm in Matlab and its subsequent evaluation in the GPS signal to determine the improvements obtained in the different types of errors that affect the signal in transmission and reception. This technique allowed to eliminate the different types of errors produced by thermal noise, multipath, refraction among others, which mainly affect receivers that work in simple frequency. To perform the differentiation, the Rinex files of the receivers located on the ground were used, for which the pseudorange measurements were extracted and the carrier phase is an estimated time, generating the code signal less called phase (CMC) and then being filtered allowing get the CMC-Smoothing signal. For the analysis of data, descriptive statistics were applied, which allowed the identification of the original and corrected signals by several algorithms by means of graphs. In conclusion, it was determined that the Kalman filter stability time values are in a range of 300 to 1800 seconds, allowing the decrease in the error in the signal to be observed, so that the larger the estimated time an improvement in the Error reduction gradually with respect to the original signal. KEYWORDS: Telecommunications; global positioning system; rinex files; Kalman filter; ionospheric error; Matlab. more...
- Published
- 2020
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