680 results on '"Roberto Iglesias"'
Search Results
2. Evaluation of the current understanding of the impact of climate change on coral physiology after three decades of experimental research
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Wiebke E. Krämer, Roberto Iglesias-Prieto, and Susana Enríquez
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Biology (General) ,QH301-705.5 - Abstract
A combination of experimental and literature analyses indicate that heat stress is a greater threat for coral calcification than ocean acidification, stressing the need for further investigation on key regulatory processes.
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- 2022
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3. Photosynthetic usable energy explains vertical patterns of biodiversity in zooxanthellate corals
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Tomás López-Londoño, Kelly Gómez-Campo, Xavier Hernández-Pech, Susana Enríquez, and Roberto Iglesias-Prieto
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Medicine ,Science - Abstract
Abstract The biodiversity in coral reef ecosystems is distributed heterogeneously across spatial and temporal scales, being commonly influenced by biogeographic factors, habitat area and disturbance frequency. A potential association between gradients of usable energy and biodiversity patterns has received little empirical support in these ecosystems. Here, we analyzed the productivity and biodiversity variation over depth gradients in symbiotic coral communities, whose members rely on the energy translocated by photosynthetic algal symbionts (zooxanthellae). Using a mechanistic model we explored the association between the depth-dependent variation in photosynthetic usable energy to corals and gradients of species diversity, comparing reefs with contrasting water clarity and biodiversity patterns across global hotspots of marine biodiversity. The productivity-biodiversity model explained between 64 and 95% of the depth-related variation in coral species richness, indicating that much of the variation in species richness with depth is driven by changes in the fractional contribution of photosynthetically fixed energy by the zooxanthellae. These results suggest a fundamental role of solar energy availability and photosynthetic production in explaining global-scale patterns of coral biodiversity and community structure along depth gradients. Accordingly, the maintenance of water optical quality in coral reefs is fundamental to protect coral biodiversity and prevent reef degradation.
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- 2022
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4. Bilateral external iliac artery pseudoaneurysms causing urinary obstruction and acute renal failure
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Marcelo Puppo Bigarella, Roberto Iglesias Lopes, Guilherme Gentile, Carolina Brito Faustino, Lais da Cunha Gamba, Guilherme Baumgardt Barbosa Lima, Henry Augusto Hoffman Melo, and Grace Carvajal Mulatti
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Ruptured pseudoaneurysm ,External iliac artery ,Ureteral obstruction ,Bilateral ureterohydronephrosis ,Endovascular repair ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Abstract Background We report an exceedingly rare case of bilateral external iliac artery pseudoaneurysms causing urinary obstruction and acute renal failure. Case presentation A young man presented with acute severe bilateral testicular pain radiating to the back. Clinical and radiological workup showed bilateral external iliac artery pseudoaneurysms, which caused bilateral ureterohydronephrosis due to urinary obstruction with subsequent renal failure. Management included immediate bilateral external iliac artery endovascular repair and bilateral ureterolysis using a retroperitoneal approach, with resolution of the obstruction and successful endovascular treatment of both pseudoaneurysms. The only identifiable risk factor for cardiovascular disease was cocaine addiction. Conclusions This case highlights an unusual and severe clinical presentation of bilateral EIA pseudoaneurysms causing bilateral ureterohydronephrosis and subsequent renal failure. Awareness of this condition may help avoid misdiagnosis and delayed management, which is of utmost importance for a favorable outcome.
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- 2022
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5. Evaluating TIMP-2 and IGFBP-7 as a predictive tool for kidney injury in ureteropelvic junction obstruction
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Marcos Figueiredo Mello, José de Bessa Júnior, Sabrina T. Reis, Enzo Yagi Kondo, Luis Yu, Francisco Tibor Dénes, and Roberto Iglesias Lopes
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Cakut [Supplementary Concept] ,Urinary Tract ,Child ,Biomarkers ,Diseases of the genitourinary system. Urology ,RC870-923 - Abstract
ABSTRACT A major challenge in the management of ureteropelvic junction obstruction (UPJO) is the selection of patients who would benefit from surgical treatment. Tissue inhibitor metalloproteinase-2 (TIMP-2) and insulin-like growth factor-binding protein 7 (IGFBP7) indicate renal cell stress and are associated with cell cycle arrest. The [TIMP-2] [IGFBP7] ratio (Nephrocheck®) has been recently applied in patients in intensive care units patients to predict the development of acute kidney injury. In this study, we evaluated the performance of these biomarkers performance to distinguishing obstructive hydronephrosis (HN) from non-obstructive HN. Materials and Methods: Consecutive patients with UPJO were enrolled in this study. Urinary [TIMP-2] [IGFBP7] and clinical characteristics (hydronephrosis grade, differential renal function, and drainage half-time) were measured in the following groups: 26 children with obstructive HN at initial diagnosis (group 1A) and after six months of dismembered pyeloplasty (group 1B); 22 children with non-obstructive HN (group 2), and 26 children without any urinary tract condition, as the control group (group 3). Results: Comparing the initial samples, [TIMP-2] [IGFBP7] had higher levels in the HN groups and lower levels in the control group; however, no difference was observed between the HN groups (obstructive vs. non-obstructive). After six months of follow-up, patients who underwent dismembered pyeloplasty showed stability in the urinary concentration of [TIMP-2] [IGFBP7]. All patients with [TIMP-2] [IGFBP7] higher than 1.0 (ng/mL)2/1000 had diffuse cortical atrophy on ultrasonography. Conclusions: We showed that urinary levels of urinary [TIMP-2] [IGFBP7] are higher in children with HN than controls. Nephrocheck® is not reliable in predicting the need for surgical intervention for pediatric patients with UPJO.
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- 2022
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6. The role of the endolithic alga Ostreobium spp. during coral bleaching recovery
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Claudia Tatiana Galindo-Martínez, Michele Weber, Viridiana Avila-Magaña, Susana Enríquez, Hiroaki Kitano, Mónica Medina, and Roberto Iglesias-Prieto
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Medicine ,Science - Abstract
Abstract In this study, we explore how the Caribbean coral Orbicella faveolata recovers after bleaching, using fragments from 13 coral colonies exposed to heat stress (32 °C) for ten days. Biological parameters and coral optical properties were monitored during and after the stress. Increases in both, the excitation pressure over photosystem II (Qm) and pigment specific absorption (a*Chla ) were observed in the stressed corals, associated with reductions in light absorption at the chlorophyll a red peak (D e675 ) and symbiont population density. All coral fragments exposed to heat stress bleached but a fraction of the stressed corals recovered after removing the stress, as indicated by the reductions in Q m and increases in D e675 and the symbiont population observed. This subsample of the experimentally bleached corals also showed blooms of the endolithic algae Ostreobium spp. underneath the tissue. Using a numerical model, we quantified the amount of incident light reflected by the coral, and absorbed by the different pigmented components: symbionts, host-tissue and Ostreobium spp. Our study supports the key contribution of Ostreobium spp. blooms near the skeletal surface, to coral recovery after bleaching by reducing skeleton reflectance. Endolithic blooms can thus significantly alleviate the high light stress that affects the remaining symbionts during the stress or when the coral has achieved the bleached phenotype.
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- 2022
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7. Modulation of the symbionts light environment in hospite in scleractinian corals
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Claudia Tatiana Galindo-Martínez, Arelys Chaparro, Susana Enríquez, and Roberto Iglesias-Prieto
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coral bleaching ,coral recovery ,animal chromoproteins ,light environment in hospite ,a*CP ,Science ,General. Including nature conservation, geographical distribution ,QH1-199.5 - Abstract
The upregulation of animal chromoproteins (CPs) during thermal stress produces “colorful” bleached corals that facilitate coral recovery after bleaching. In situ measurements indicate that animal CPs present in coral tissues reduce the elevated internal light environment of the remaining symbionts in bleached or low-pigmented stressed corals. However, there is still a lack of understanding regarding the extent to which animal CPs contribute to modifying the internal light environment of the symbionts in hospite. In this study, we evaluate the effect of three animal CPs on the optical properties of the coral tissue and their internal light environment using a numerical model. The model allows estimations of the absorbance spectra of corals as a function of changes in symbiont and animal pigmentation, as well as descriptions of the light environment in hospite of the symbionts. These descriptions were derived from the quantification of the contribution of each pigment component to light absorption, together with the contribution of the coral skeleton’s reflectance. Simulations indicate that animal CPs upregulation modifies the spectral distribution and the intensity of the internal light field. Animal CPs can reduce up to 11% of the light intensity in hospite when present individually, and up to 24% when present in combination. Such reduction may play a critical role in preventing the full development of the bleached phenotype when irradiance rises to excessive levels at low coral pigmentation, facilitating coral recovery and symbiont tissue re-colonization after bleaching. Accordingly, coral’s CPs components need to also be considered when selecting coral species for future restoration efforts.
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- 2022
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8. Elucidating gene expression adaptation of phylogenetically divergent coral holobionts under heat stress
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Viridiana Avila-Magaña, Bishoy Kamel, Michael DeSalvo, Kelly Gómez-Campo, Susana Enríquez, Hiroaki Kitano, Rori V. Rohlfs, Roberto Iglesias-Prieto, and Mónica Medina
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Science - Abstract
As corals struggle to survive under climate change, it is crucial to know whether they can withstand increasing seawater temperatures. Using a controlled thermal stress experiment across three divergent coral holobionts, this study examines metatranscriptomic responses to heat stress corresponding to the coral host, photosymbionts and associated microbiota.
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- 2021
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9. Can extended upper pole ureterectomy prevent ureteral stump syndrome after proximal approach for duplex kidneys?
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Bruno Nicolino Cezarino, Roberto Iglesias Lopes, Ricardo Haidar Berjeaut, and Francisco Tibor Dénes
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Cakut [Supplementary Concept] ,Ureter ,Urinary Tract Infections ,Diseases of the genitourinary system. Urology ,RC870-923 - Abstract
ABSTRACT Introduction: Symptomatic duplex kidneys usually present with recurrent urinary tract infection due to ureteral obstruction (megaureter, ureterocele or ectopic ureter) and/or vesicoureteral reflux. Upper-pole nephrectomy is a widely accepted procedure to correct symptomatic duplex systems with poor functioning moieties, also known as upper or proximal approach. The distal ureteral stump syndrome (DUSS) can be a late complication of this approach. There is no consensus upon the length of ureteral dissection and the better approach to symptomatic disease in duplex systems, so we aim to identify if extended ureteral dissection can prevent DUSS in top-down approach. Materials and Methods: Forty-four consecutive patients with symptomatic duplex system were retrospectively classified into two groups: those with limited ureteral excision after heminephrectomy (HN) (group-1) and those with extended ureterectomy after HN (group-2). Patients were followed-up for at least 36 months regarding outcomes of distal ureteral stump. Results: Overall complication was 20%. A total of 8 patients required unplanned further surgery in Group-1 (30%) whereas only 1 patient required unplanned surgery in group 2 (6%) (p=0.07). Subgroup analysis showed that Group-1 presented more DUSS requiring surgery during follow-up than group-2 (p=0.04). Factors possibly affecting complications incidence (such as ureterocele or ectopic ureter) did not differ between groups (p=0.72 and p=0.78). Conclusion: Upper pole nephrectomy should be performed with extended distal ureteral dissection to prevent ureteral stump complications.
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- 2021
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10. Patients with encrusted ureteral stents can be treated by a single session combined endourological approach
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Roberto Iglesias Lopes, Rodrigo Perrella, Carlos Hirokatsu Watanabe, Fabricio Beltrame, Alexandre Danilovic, Claudio Bovolenta Murta, Joaquim Francisco de Almeida Claro, and Fabio Carvalho Vicentini
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Stents ,Ureter ,Nephrolithotomy, Percutaneous ,Diseases of the genitourinary system. Urology ,RC870-923 - Abstract
ABSTRACT Purpose: To describe our experience in the management of retained encrusted ureteral stents using a single session combined endourological approach. Materials and Methods: Patients with retained encrusted ureteral stents who had been submitted to a single session combined endourological approach from June 2010 to June 2018 were prospectively evaluated. Patients were divided according to the Forgotten-Encrusted-Calcified (FECal) classification. The stone burden, surgical intervention, number of interventions until stone free status, operation time, hospital stay, complications, stone analysis, and stone-free rate were compared between groups. ANOVA was used to compare numerical variables, and the Mann-Whitney or Chi-square test to compare categorical variables between groups. Results: We evaluated 50 patients with a mean follow-up of 2.9±1.4 years (mean±SD). The groups were comparable in terms of age, sex, laterality, BMI, comorbidities, ASA, reason for stent passage, and indwelling time. The stone burden was higher for grades IV and V (p=0.027). Percutaneous nephrolithotomy was the most common procedure (p=0.004) for grades IV and V. The number of procedures until the patients were stone-free was 1.92±1.40, and the hospital stay (4.2±2.5 days), complications (22%), and stone analysis (66% calcium oxalate) were similar between groups. The stone-free rate was lower in grades III to V (60%, 54.5%, and 50%). Conclusions: The endoscopic combined approach in the supine position is a safe and feasible technique that allows removal of retained and encrusted stents in a single procedure. The FECal classification seems to be useful for surgical planning.
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- 2021
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11. Linking photoacclimation responses and microbiome shifts between depth-segregated sibling species of reef corals
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Carlos Prada, Tomás López-Londoño, F. Joseph Pollock, Sofia Roitman, Kim B. Ritchie, Don R. Levitan, Nancy Knowlton, Cheryl Woodley, Roberto Iglesias-Prieto, and Mónica Medina
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corals ,symbiosis ,microbiome ,photobiology ,ecophysiology ,niche divergence ,Science - Abstract
Metazoans host complex communities of microorganisms that include dinoflagellates, fungi, bacteria, archaea and viruses. Interactions among members of these complex assemblages allow hosts to adjust their physiology and metabolism to cope with environmental variation and occupy different habitats. Here, using reciprocal transplantation across depths, we studied adaptive divergence in the corals Orbicella annularis and O. franksi, two young species with contrasting vertical distribution in the Caribbean. When transplanted from deep to shallow, O. franksi experienced fast photoacclimation and low mortality, and maintained a consistent bacterial community. By contrast, O. annularis experienced high mortality and limited photoacclimation when transplanted from shallow to deep. The photophysiological collapse of O. annularis in the deep environment was associated with an increased microbiome variability and reduction of some bacterial taxa. Differences in the symbiotic algal community were more pronounced between coral species than between depths. Our study suggests that these sibling species are adapted to distinctive light environments partially driven by the algae photoacclimation capacity and the microbiome robustness, highlighting the importance of niche specialization in symbiotic corals for the maintenance of species diversity. Our findings have implications for the management of these threatened Caribbean corals and the effectiveness of coral reef restoration efforts.
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- 2022
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12. A Road Map for the Development of the Bleached Coral Phenotype
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Kelly Gómez-Campo, Susana Enríquez, and Roberto Iglesias-Prieto
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oxidative stress ,seasonal phenotype ,coral bleaching ,ROS ,bleached coral phenotype ,Science ,General. Including nature conservation, geographical distribution ,QH1-199.5 - Abstract
Mass coral bleaching compromises the long-term persistence of coral reefs, yet our current understanding of the different cellular mechanisms leading to the development of a bleached coral is still limited. In this perspective, we mapped the cascade of cellular events and physiological responses of symbiotic corals triggered by thermal stress. Based on existing knowledge, we created an integrated model that describes phenotypic changes induced by sensing mechanisms. Cellular responses are mapped in the context of reactive oxygen species (ROS) production in the algal symbiont chloroplast, followed by signaling to the nucleus and subsequent “leak” to the coral host cell. The starting point is set by ROS production and signaling, which is a day-to-day mechanism by which symbiotic corals maintain homeostasis and acclimate to environmental variation. As stress and acclimation are intimately linked, our model maps coral responses from the initial stimulus in the chloroplast to the complex cascade of events leading to seasonal phenotypic changes (i.e., seasonal acclimation), and if stress progresses, to the downstream coral bleached phenotype (i.e., when the coral’s capacity to acclimate is overwhelmed by heat stress). Placing acclimation, heat stress and bleaching responses in a common ground is a critical step to reduce the source of uncertainty in understanding the coral response to climate change, fundamental for the development of predictive climate models.
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- 2022
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13. Influence of low free thyroxine on progression of chronic kidney disease
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Alexandre Barbosa Câmara de Souza, Marcia Fernanda Arantes, Roberto Zatz, Rosilene Motta Elias, Roberto Iglesias Lopes, and Etienne Macedo
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Diseases of the genitourinary system. Urology ,RC870-923 - Abstract
Abstract Background Hypothyroidism is highly prevalent in patients with chronic kidney disease (CKD) and has been associated with poorer clinical outcomes, including faster decline of kidney function. However, there is no consensus whether low free thyroxin (LFT) affects the rate of estimated glomerular filtration rate (eGFR) decline and how the presence of proteinuria influences the progression of renal dysfunction in hypothyroidism. Methods We assessed thyroid status, proteinuria, and progression of eGFR by Modification of Diet in Renal Disease equation and CKD-EPI equation in a cohort of CKD patients followed in general nephrology clinics. We estimated the association of LFT levels, and the degree of proteinuria on progression of eGFR. We adjusted for other covariables: age, gender, body mass index, diabetes, hypertension, HbA1c, uric acid, cholesterol, and triglycerides levels.. Results One thousand six hundred ten patients (64 ± 15 years, 46.8% men, 25.3% diabetic) were included. At beggnining of follow up eGFR was between 45 and 60, 30–45 and 15-30 ml/min/1.73m2 in 479 (29.8%), 551(34.2%), and 580(36.0%) patients, respectively. LFT levels were available at initial evaluation in 288(17.9%) patients and 735(48.5%) had assessment of proteinuria (19.6% with LFT vs. 15.4% without LFT, p = 0.032). Median follow-up time was of 21 months, and 1223(76%) had at least 1 year of follow up. Overall, eGFR decline per month was − 0.05(− 0.26, 0.23) ml/min/1.73m2, reaching 1.7(1.3, 2.4) ml/min/1.73m2 by the end of study period. Similar results were obtained using CKD-EPI. Multivariable mixed linear analysis showed that proteinuria and age were independently associated with eGFR decline, with no effect of LFT, and no interaction between proteinuria and LFT. In patients without proteinuria, there was an improvement of eGFR despite the presence of LFT. Conclusions We confirmed a faster rate of eGFR declined in patients with proteinuria. However, despite the pathophysiological rational that hypothyroidism can lead to increased rate of CKD progression, we failed to demonstrate an association between LFT and rate of CKD progression. We conclude that the benefit of hypothyroidism treatment in CKD patients needs to be evaluate in prospective studies.
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- 2020
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14. Materials to Be Used in Future Magnetic Confinement Fusion Reactors: A Review
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René Alba, Roberto Iglesias, and María Ángeles Cerdeira
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PFM ,structural materials ,RAFM ,ODS ,SiC ,vanadium alloys ,Technology ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Microscopy ,QH201-278.5 ,Descriptive and experimental mechanics ,QC120-168.85 - Abstract
This paper presents the roadmap of the main materials to be used for ITER and DEMO class reactors as well as an overview of the most relevant innovations that have been made in recent years. The main idea in the EUROfusion development program for the FW (first wall) is the use of low-activation materials. Thus far, several candidates have been proposed: RAFM and ODS steels, SiC/SiC ceramic composites and vanadium alloys. In turn, the most relevant diagnostic systems and PFMs (plasma-facing materials) will be described, all accompanied by the corresponding justification for the selection of the materials as well as their main characteristics. Finally, an outlook will be provided on future material development activities to be carried out during the next phase of the conceptual design for DEMO, which is highly dependent on the success of the IFMIF-DONES facility, whose design, operation and objectives are also described in this paper.
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- 2022
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15. Recent advances in pediatric bladder malignancies [version 1; peer review: 2 approved]
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Roberto Iglesias Lopes, Marcos Figueiredo Mello, and Armando J. Lorenzo
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Medicine ,Science - Abstract
Urothelial pediatric neoplasms are relatively rare. Papillary urothelial neoplasms of low malignant potential (PUNLMPs) and rhabdomyosarcoma (RMS) are the most common bladder malignancies in the pediatric population. Clinical presentation encompasses macroscopic hematuria or lower urinary tract symptoms (or both) or is detected incidentally at imaging. Tumors arising from the bladder can originate from any of its four histological layers (urothelium, lamina propria, detrusor, and adventitia) and are divided into tumors that have an epithelial origin (arising from the urothelium) and those that have a non-epithelial origin (mesenchymal neoplasms). RMS is the most common malignant tumor of the urinary bladder in children younger than 10 years. Deriving from the embryonic mesenchymal cell, the histopathologic subtypes of RMS are embryonal RMS (>90%) and alveolar histology (
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- 2020
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16. Multi Actor-Critic DDPG for Robot Action Space Decomposition: A Framework to Control Large 3D Deformation of Soft Linear Objects
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Daniel, Mélodie, Magassouba, Aly, Aranda, Miguel, Lequièvre, Laurent, Ramon, Juan Antonio Corrales, Rodriguez, Roberto Iglesias, and Mezouar, Youcef
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Computer Science - Robotics - Abstract
Robotic manipulation of deformable linear objects (DLOs) has great potential for applications in diverse fields such as agriculture or industry. However, a major challenge lies in acquiring accurate deformation models that describe the relationship between robot motion and DLO deformations. Such models are difficult to calculate analytically and vary among DLOs. Consequently, manipulating DLOs poses significant challenges, particularly in achieving large deformations that require highly accurate global models. To address these challenges, this paper presents MultiAC6: a new multi Actor-Critic framework for robot action space decomposition to control large 3D deformations of DLOs. In our approach, two deep reinforcement learning (DRL) agents orient and position a robot gripper to deform a DLO into the desired shape. Unlike previous DRL-based studies, MultiAC6 is able to solve the sim-to-real gap, achieving large 3D deformations up to 40 cm in real-world settings. Experimental results also show that MultiAC6 has a 66\% higher success rate than a single-agent approach. Further experimental studies demonstrate that MultiAC6 generalizes well, without retraining, to DLOs with different lengths or materials., Comment: 9 pages, 7 figures, 5 tables, Accepted for IEEE Robotics and Automation Letters (RA-L)
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- 2023
17. Seasonal variation modulates coral sensibility to heat-stress and explains annual changes in coral productivity
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Tim Scheufen, Wiebke E. Krämer, Roberto Iglesias-Prieto, and Susana Enríquez
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Medicine ,Science - Abstract
Abstract The potential effects of seasonal acclimatization on coral sensitivity to heat-stress, has received limited attention despite differing bleaching thresholds for summer and winter. In this study, we examined the response of two contrasting phenotypes, termed winter and summer, of four Caribbean reef corals to similar light and heat-stress levels. The four species investigated were categorized into two groups: species with the ability to harbour large number of symbionts, Orbicella annularis and O. faveolata, and species with reduced symbiont density (Montastraea cavernosa and Pseudodiploria strigosa). The first group showed higher capacity to enhance photosynthetic rates per area (Pmax), while Pmax enhancement in the second group was more dependent on Symbiodinium performance (Psym). In summer all four species presented higher productivity, but also higher sensitivity to lose coral photosynthesis under heat-stress. In contrast, corals in winter exhibit symbionts with higher capacity to photoacclimate to the increased levels of light-stress elicited by heat-stress. Overall, our study supports the importance of the acclimatory coral condition in addition to the previous thermal history, to determine the severity of the impact of heat-stress on coral physiology, but also the dependence of this response on the particular structural and functional traits of the species.
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- 2017
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18. The Critical Raw Materials in Cutting Tools for Machining Applications: A Review
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Antonella Rizzo, Saurav Goel, Maria Luisa Grilli, Roberto Iglesias, Lucyna Jaworska, Vjaceslavs Lapkovskis, Pavel Novak, Bogdan O. Postolnyi, and Daniele Valerini
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critical raw materials ,cutting tools ,new materials ,new machining methods ,modelling and simulation ,Technology ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Microscopy ,QH201-278.5 ,Descriptive and experimental mechanics ,QC120-168.85 - Abstract
A variety of cutting tool materials are used for the contact mode mechanical machining of components under extreme conditions of stress, temperature and/or corrosion, including operations such as drilling, milling turning and so on. These demanding conditions impose a seriously high strain rate (an order of magnitude higher than forming), and this limits the useful life of cutting tools, especially single-point cutting tools. Tungsten carbide is the most popularly used cutting tool material, and unfortunately its main ingredients of W and Co are at high risk in terms of material supply and are listed among critical raw materials (CRMs) for EU, for which sustainable use should be addressed. This paper highlights the evolution and the trend of use of CRMs) in cutting tools for mechanical machining through a timely review. The focus of this review and its motivation was driven by the four following themes: (i) the discussion of newly emerging hybrid machining processes offering performance enhancements and longevity in terms of tool life (laser and cryogenic incorporation); (ii) the development and synthesis of new CRM substitutes to minimise the use of tungsten; (iii) the improvement of the recycling of worn tools; and (iv) the accelerated use of modelling and simulation to design long-lasting tools in the Industry-4.0 framework, circular economy and cyber secure manufacturing. It may be noted that the scope of this paper is not to represent a completely exhaustive document concerning cutting tools for mechanical processing, but to raise awareness and pave the way for innovative thinking on the use of critical materials in mechanical processing tools with the aim of developing smart, timely control strategies and mitigation measures to suppress the use of CRMs.
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- 2020
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19. Walking Recognition in Mobile Devices
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Fernando E. Casado, Germán Rodríguez, Roberto Iglesias, Carlos V. Regueiro, Senén Barro, and Adrián Canedo-Rodríguez
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walking recognition ,activity recognition ,smartphones ,inertial sensor fusion ,pattern classification ,time series classification. ,Chemical technology ,TP1-1185 - Abstract
Presently, smartphones are used more and more for purposes that have nothing to do with phone calls or simple data transfers. One example is the recognition of human activity, which is relevant information for many applications in the domains of medical diagnosis, elderly assistance, indoor localization, and navigation. The information captured by the inertial sensors of the phone (accelerometer, gyroscope, and magnetometer) can be analyzed to determine the activity performed by the person who is carrying the device, in particular in the activity of walking. Nevertheless, the development of a standalone application able to detect the walking activity starting only from the data provided by these inertial sensors is a complex task. This complexity lies in the hardware disparity, noise on data, and mostly the many movements that the smartphone can experience and which have nothing to do with the physical displacement of the owner. In this work, we explore and compare several approaches for identifying the walking activity. We categorize them into two main groups: the first one uses features extracted from the inertial data, whereas the second one analyzes the characteristic shape of the time series made up of the sensors readings. Due to the lack of public datasets of inertial data from smartphones for the recognition of human activity under no constraints, we collected data from 77 different people who were not connected to this research. Using this dataset, which we published online, we performed an extensive experimental validation and comparison of our proposals.
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- 2020
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20. Changes over time in illicit cigarette use in Brazil, overall and by educational level: proposed novel approach and results
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Andre Szklo, Roberto Iglesias, Mirian de Souza, Moyses Szklo, and Liz Maria de Almeida
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WCTOH ,Diseases of the respiratory system ,RC705-779 ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Background The strategy of raising taxes has reduced smoking prevalence in Brazil in the last few years. However, given the presence of illicit cigarette products in Brazil, smokers may have migrated to cheaper illicit cigarettes in order to save money, thus undermining efforts to further reduce smoking prevalence, mostly among underprivileged smokers. The aim of the present study was to estimate the proportions of illicit cigarette consumption in Brazil from 2012 to 2016. Methods We used an approach based on legal sales provided by the Secretariat of Federal Revenues and self-reported consumption data from a phone survey conducted annually (VIGITEL) to estimate the changes over time in illegal cigarette use in Brazil, overall and by educational level. For that purpose, we also used available information on the proportion of illegal cigarette consumption from a nationwide household survey conducted in 2013 to calculate a constant proportion of under-reporting from VIGITEL in relation to total sales in Brazil. Results There was an increase in the estimated proportion of illicit cigarette use from 2012 to 2013 (+12.9%), then a decrease from 2013 to 2014 (-10.8%), and then a sustained trend of increase from 2014 to 2016 (+26.7%, from 2014 to 2015; +17.3%, from 2015 to 2016).The same pattern was observed for both high and low educational level smokers. For each year, the latter had higher baseline proportions of illegal cigarette use. Conclusions Novel and feasible approaches to estimate the changes over time in illegal market are important to help in the effective implementation of tobacco excise tax policy.
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- 2018
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21. Characterization of cigarrete smuggling distribution in Colombia
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Blanca Llorente, Diana Díaz, Luis Fernando de Angulo, Roberto Iglesias, and Maria Clara Ávila
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WCTOH ,Diseases of the respiratory system ,RC705-779 ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Background The challenges associated with a historical pattern of interaction between the State and the territory, predominance of informal cigarette sales, corruption and well-organized mafias, create favorable conditions for illicit trade of cigarettes in Colombia. Guajira encompasses all this elements and it is the most traditional smuggling hub. The study also includes the cities of Cúcuta (close to the Venezuelan border with 23% penetration of illicit cigarettes), and Bogotá (with the largest number of smokers) This study identifies actors in the illicit trade distribution chain (retail and wholesale), their behaviour, incentives and interactions. Methods Passive participant research (e.g. buying cigarettes), semi-structured interviews, and focus groups. Fieldwork performed between July - November 2017. Selected actors include authorities, smugglers, travelers in border areas, street vendors and owners of small businesses. Results Preliminary findings obtained from interviews reveal three significative changes in Guajira: military and police forces have rearranged priorities in the territory as a result of the dynamics of the peace process; communities acknowledge the need of State action to preserve order, but smuggling continues to be the exception (e.g. reports of violent incidents between communities and police after seizure operatives); traditional leaders' profile is undergoing transformations. Economic slowdown, and dererioriating environmental conditions are mentioned as driving forces for a renewed presence of smuggling activity in the region. Findings reveal presence of minors in smuggling activities. In Bogotá street vendors (the main distribution channel for cigarettes) after the tax increase are more reluctant to sell full packs. Conclusions Changes along the distribution chain are bringing new risks and opportunities for an effective control of illicit trade flows. It is necessary to explore interventions that address institutional weaknesses, and the circumstances of vulnerable actors to develop sustainable policies to eliminate illicit trade in Colombia.
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- 2018
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22. Unraveling the structure and composition of Varadero Reef, an improbable and imperiled coral reef in the Colombian Caribbean
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Valeria Pizarro, Sara C. Rodríguez, Mateo López-Victoria, Fernando A. Zapata, Sven Zea, Claudia T. Galindo-Martínez, Roberto Iglesias-Prieto, Joseph Pollock, and Mónica Medina
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Caribbean coral reefs ,Coral reef biodiversity ,Reef dredging ,Paradoxical reef ,Resistance ,Medicine ,Biology (General) ,QH301-705.5 - Abstract
Coral reefs are commonly associated with oligotrophic, well-illuminated waters. In 2013, a healthy coral reef was discovered in one of the least expected places within the Colombian Caribbean: at the entrance of Cartagena Bay, a highly-polluted system that receives industrial and sewage waste, as well as high sediment and freshwater loads from an outlet of the Magdalena River (the longest and most populated river basin in Colombia). Here we provide the first characterization of Varadero Reef’s geomorphology and biological diversity. We also compare these characteristics with those of a nearby reference reef, Barú Reef, located in an area much less influenced by the described polluted system. Below the murky waters, we found high coral cover of 45.1% (±3.9; up to 80% in some sectors), high species diversity, including 42 species of scleractinian coral, 38 of sponge, three of lobster, and eight of sea urchin; a fish community composed of 61 species belonging to 24 families, and the typical zonation of a Caribbean fringing reef. All attributes found correspond to a reef that, according to current standards should be considered in “good condition”. Current plans to dredge part of Varadero threaten the survival of this reef. There is, therefore, an urgent need to describe the location and characteristics of Varadero as a first step towards gaining acknowledgement of its existence and garnering inherent legal and environmental protections.
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- 2017
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23. Mobile Robot Positioning with 433-MHz Wireless Motes with Varying Transmission Powers and a Particle Filter
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Adrian Canedo-Rodriguez, Jose Manuel Rodriguez, Victor Alvarez-Santos, Roberto Iglesias, and Carlos V. Regueiro
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wireless localization ,WiFi localization ,motes ,particle filters ,robot localization ,Chemical technology ,TP1-1185 - Abstract
In wireless positioning systems, the transmitter’s power is usually fixed. In this paper, we explore the use of varying transmission powers to increase the performance of a wireless localization system. To this extent, we have designed a robot positioning system based on wireless motes. Our motes use an inexpensive, low-power sub-1-GHz system-on-chip (CC1110) working in the 433-MHz ISM band. Our localization algorithm is based on a particle filter and infers the robot position by: (1) comparing the power received with the expected one; and (2) integrating the robot displacement. We demonstrate that the use of transmitters that vary their transmission power over time improves the performance of the wireless positioning system significantly, with respect to a system that uses fixed power transmitters. This opens the door for applications where the robot can localize itself actively by requesting the transmitters to change their power in real time.
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- 2015
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24. INITIAL EXPERIENCE WITH ENDOSCOPIC ULTRASOUND-GUIDED FINE NEEDLE ASPIRATION OF RENAL MASSES: indications, applications and limitations
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Renata Nobre MOURA, Roberto Iglesias LOPES, Miguel SROUGI, Marcos Francisco DALL'OGLIO, Paulo SAKAI, and Everson L A ARTIFON
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Neoplasias renais, diagnósticos ,Ultrassonografia ,Aspiração por agulha fina guiada por ultrassom endoscópico ,Diseases of the digestive system. Gastroenterology ,RC799-869 - Abstract
Context Tissue sampling of renal masses is traditionally performed via the percutaneous approach or laparoscopicaly. The utility of endoscopic ultrasound to biopsy renal lesions it remains unclear and few cases have been reported. Objectives To evaluate the feasibility and outcome of endoscopic ultrasound fine needle aspiration of renal tumors. Methods Consecutive subjects undergoing attempted endoscopic ultrasound fine needle aspiration of a kidney mass after evaluation with computerized tomography or magnetic resonance. Results Ten procedures were performed in nine male patients (median age 54.7 years) on the right (n = 4) and left kidney (n = 4) and bilaterally (n = 1). Kidney masses (median diameter 55 mm ; range 13-160 mm) were located in the upper pole (n = 3), the lower pole (n = 2) and the mesorenal region (n = 3). In two cases, the mass involved more than one kidney region. Surgical resection confirmed renal cell carcinoma in six patients in whom pre-operative endoscopic ultrasound fine needle aspiration demonstrated renal cell carcinoma. No complications were reported. Conclusions Endoscopic ultrasound fine needle aspiration appears as a safe and feasible procedure with good results and minimal morbidity.
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- 2014
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25. Changes in the Number of Symbionts and Symbiodinium Cell Pigmentation Modulate Differentially Coral Light Absorption and Photosynthetic Performance
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Tim Scheufen, Roberto Iglesias-Prieto, and Susana Enríquez
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light absorption ,scleractinian coral ,symbiont population ,symbiont cell pigmentation ,optical traits ,Science ,General. Including nature conservation, geographical distribution ,QH1-199.5 - Abstract
In order to understand the contribution of pigmented coral tissues to the extraordinary optical properties of the coral-symbiont-skeleton unit, we analyzed the associations between structural and optical traits for four coral species, which broadly differ in skeleton morphology, tissue thickness and in the variation of coral pigmentation, symbiont content, Symbiodinium dominant type and Symbiodinium cell pigmentation (Ci). Significant differences among species were found for the maximum capacity of light absorption (Amax) and for the minimum pigmentation required to reach that maximum. The meandroid morphotype represented by Pseudodiploria strigosa showed a slightly lower Amax than the other three chalice-type species, while the thickest species, Montastraea cavernosa, required 2–3.5 times higher pigmentation to reach Amax. In contrast, Orbicella faveolata and Orbicella annularis, which were able to harbor high number of symbionts and achieve the highest photosynthetic rates per area, showed the largest abilities for light collection at decreasing symbiont densities, leading to a more fragile photophysiological condition under light and heat-stress. Holobiont photosynthesis was more dependent on Symbiodinium performance in the less populated organisms. At reduced pigmentation, we observed a similar non-linear increase in holobiont light absorption efficiency (a*Chla), which was differentially modulated by reductions in the number of symbionts and Symbiodinium Ci. For similar pigmentation, larger symbiont losses relative to Ci declines resulted in smaller increases in a*Chla. Two additional optical traits were used to characterize light absorption efficiency of Symbiodinium (a*sym) and coral host (a*M). Optimization of a*sym was well represented by P. strigosa, whereas a*M was better optimized by O. annularis. The species with the largest symbiont content, O. faveolata, and with the thickest tissues, M. cavernosa, represented, respectively, less efficient solutions for both coral traits. Our comparison demonstrates the utility of optical traits to characterize inter-specific differences in coral acclimatization and performance. Furthermore, holobiont light absorption efficiency (a*Chla) appeared as a better proxy for the “bleached phenotype” than simple reductions in coral color. The analysis of a putative coordinated variation in the number of symbionts and in Symbiodinium cell pigmentation deserves special attention to understand holobiont optimization of energy collection (a*Chla) and photosynthetic performance.
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- 2017
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26. The effects of elevated seawater temperatures on Caribbean gorgonian corals and their algal symbionts, Symbiodinium spp.
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Tamar L Goulet, Kartick P Shirur, Blake D Ramsby, and Roberto Iglesias-Prieto
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Medicine ,Science - Abstract
Global climate change not only leads to elevated seawater temperatures but also to episodic anomalously high or low temperatures lasting for several hours to days. Scleractinian corals are detrimentally affected by thermal fluctuations, which often lead to an uncoupling of their mutualism with Symbiodinium spp. (coral bleaching) and potentially coral death. Consequently, on many Caribbean reefs scleractinian coral cover has plummeted. Conversely, gorgonian corals persist, with their abundance even increasing. How gorgonians react to thermal anomalies has been investigated utilizing limited parameters of either the gorgonian, Symbiodinium or the combined symbiosis (holobiont). We employed a holistic approach to examine the effect of an experimental five-day elevated temperature episode on parameters of the host, symbiont, and the holobiont in Eunicea tourneforti, E. flexuosa and Pseudoplexaura porosa. These gorgonian corals reacted and coped with 32°C seawater temperatures. Neither Symbiodinium genotypes nor densities differed between the ambient 29.5°C and 32°C. Chlorophyll a and c2 per Symbiodinium cell, however, were lower at 32°C leading to a reduction in chlorophyll content in the branches and an associated reduction in estimated absorbance and increase in the chlorophyll a specific absorption coefficient. The adjustments in the photochemical parameters led to changes in photochemical efficiencies, although these too showed that the gorgonians were coping. For example, the maximum excitation pressure, Qm, was significantly lower at 32°C than at 29.5°C. In addition, although per dry weight the amount of protein and lipids were lower at 32°C, the overall energy content in the tissues did not differ between the temperatures. Antioxidant activity either remained the same or increased following exposure to 32°C further reiterating a response that dealt with the stressor. Taken together, the capability of Caribbean gorgonian corals to modify symbiont, host and consequently holobiont parameters may partially explain their persistence on reefs faced with climate change.
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- 2017
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27. Robust and Fast Scene Recognition in Robotics Through the Automatic Identification of Meaningful Images
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David Santos, Eric Lopez-Lopez, Xosé M. Pardo, Roberto Iglesias, Senén Barro, and Xosé R. Fdez-Vidal
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scene recognition ,image collection summarization ,meaningful images ,Chemical technology ,TP1-1185 - Abstract
Scene recognition is still a very important topic in many fields, and that is definitely the case in robotics. Nevertheless, this task is view-dependent, which implies the existence of preferable directions when recognizing a particular scene. Both in human and computer vision-based classification, this actually often turns out to be biased. In our case, instead of trying to improve the generalization capability for different view directions, we have opted for the development of a system capable of filtering out noisy or meaningless images while, on the contrary, retaining those views from which is likely feasible that the correct identification of the scene can be made. Our proposal works with a heuristic metric based on the detection of key points in 3D meshes (Harris 3D). This metric is later used to build a model that combines a Minimum Spanning Tree and a Support Vector Machine (SVM). We have performed an extensive number of experiments through which we have addressed (a) the search for efficient visual descriptors, (b) the analysis of the extent to which our heuristic metric resembles the human criteria for relevance and, finally, (c) the experimental validation of our complete proposal. In the experiments, we have used both a public image database and images collected at our research center.
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- 2019
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28. [Untitled]
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Fabio Cesar Miranda Torricelli, Enrico Martins de Andrade, Giovanni Scala Marchini, Roberto Iglesias Lopes, Joaquim Francisco Almeida Claro, Jose Cury, and Miguel Srougi
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Implante peniano ,Polimetil metacrilato ,Pênis ,Disfunção erétil ,Doenças do pênis ,Penile implantation ,Polymethyl methacrylate ,Penis ,Erectile dysfunction ,Penile diseases ,Medicine - Abstract
CONTEXTPenis size is a great concern for men in many cultures. Despite the great variety of methods for penile augmentation, none has gained unanimous acceptance among experts in the field. However, in this era of minimally invasive procedure, injection therapy for penile augmentation has become more popular. Here we report a case of methacrylate injection in the penis that evolved with penile deformity and sexual dysfunction. This work also reviews the investigation and management of this pathological condition.CASE REPORTA 36-year-old male sought medical care with a complaint of penile deformity and sexual dysfunction after methacrylate injection. The treatment administered was surgical removal. Satisfactory cosmetic and functional results were reached after two months.CONCLUSIONSThere is a need for better structured scientific research to evaluate the outcomes and complication rates from all penile augmentation procedures.CONTEXTOO tamanho peniano é uma grande preocupação para homens em diversas culturas. Apesar da grande variedade de possíveis métodos para o aumento peniano, nenhum ganhou aceitação unânime por especialistas no assunto. Mas na era dos procedimentos minimamente invasivos, a terapia de injeção para aumento peniano tem se tornado mais popular. Aqui relatamos um caso de injeção de metacrilato no pênis que evoluiu com deformidade peniana e disfunção sexual. Este trabalho também revisa a investigação e gerenciamento desta afecção.RELATO DE CASOUm homem de 36 anos procurou atendimento médico com queixa de deformidade peniana e disfunção sexual após injeção de metacrilato. Remoção cirúrgica foi realizada como tratamento. Após dois meses, satisfatórios resultados cosmético e funcional foram alcançados.CONCLUSÃOTrabalhos científicos mais bem estruturados para avaliar as taxas de complicação e resultados de todos os procedimentos para aumento peniano são necessários.
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- 2013
29. Self-Organized Multi-Camera Network for a Fast and Easy Deployment of Ubiquitous Robots in Unknown Environments
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Xose Manuel Pardo, Victor Alvarez-Santos, Carlos V. Regueiro, Roberto Iglesias, and Adrián Canedo-Rodriguez
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robot deployment ,robot detection and tracking ,multi-camera networks ,ambient intelligence ,ubiquitous robots ,Chemical technology ,TP1-1185 - Abstract
To bring cutting edge robotics from research centres to social environments, the robotics community must start providing affordable solutions: the costs must be reduced and the quality and usefulness of the robot services must be enhanced. Unfortunately, nowadays the deployment of robots and the adaptation of their services to new environments are tasks that usually require several days of expert work. With this in view, we present a multi-agent system made up of intelligent cameras and autonomous robots, which is easy and fast to deploy in different environments. The cameras will enhance the robot perceptions and allow them to react to situations that require their services. Additionally, the cameras will support the movement of the robots. This will enable our robots to navigate even when there are not maps available. The deployment of our system does not require expertise and can be done in a short period of time, since neither software nor hardware tuning is needed. Every system task is automatic, distributed and based on self-organization processes. Our system is scalable, robust, and flexible to the environment. We carried out several real world experiments, which show the good performance of our proposal.
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- 2012
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30. Splenogonadal fusion and testicular cancer: case report and review of the literature
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Roberto Iglesias Lopes, Mabel Tatty de Medeiros, Marco Antônio Arap, Marcello Cocuzza, Miguel Srougi, and Jorge Hallak
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Infertility, male ,Azoospermia ,Crypthorchidism ,Testicular neoplasms ,Spleen ,Testis ,Laparoscopy ,Microdissection ,Magnetic resonance imaging ,Case reports ,Medicine - Abstract
A 36 year-old man after tests for assessing male infertility was diagnosed with primary infertility, bilateral cryptorchidism, non-obstructive azoospermia and discontinuous splenogonadal fusion. Carcinoma in situ was found in his left testicle, which was intra-abdominal and associated with splenogonadal fusion. To our knowledge, this is the fourth case of splenogonadal fusion associated with testicular cancer reported. One should always bear in mind the possibility of this association for the left cryptorchid testicle.
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- 2012
31. Evolução da função pulmonar após tratamento com goserelina em pacientes com linfangioleiomiomatose Evolution of pulmonary function after treatment with goserelin in patients with lymphangioleiomyomatosis
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Bruno Guedes Baldi, Pedro Medeiros Junior, Suzana Pinheiro Pimenta, Roberto Iglesias Lopes, Ronaldo Adib Kairalla, and Carlos Roberto Ribeiro Carvalho
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Linfangioleiomiomatose ,Espirometria ,Gosserrelina ,Lymphangioleiomyomatosis ,Spirometry ,Goserelin ,Diseases of the respiratory system ,RC705-779 - Abstract
Nas células musculares lisas atípicas características da linfangioleiomiomatose (LAM) encontram-se receptores de estrogênio e progesterona, de modo que o tratamento anti-hormonal pode ser considerado uma opção, mas ainda com resultados controversos. O objetivo deste trabalho foi avaliar retrospectivamente parâmetros hormonais e espirométricos em nove mulheres com LAM após o tratamento com goserelina por um ano. Houve um aumento médio de 80 mL e 130 mL, respectivamente, em VEF1 e CVF, assim como bloqueio hormonal efetivo. Ainda não se pode excluir um potencial efeito favorável da utilização de análogos de hormônio liberador de gonadotrofina em pacientes com LAM, reforçando a necessidade de ensaios randomizadosIn the atypical smooth muscle cells that are characteristic of lymphangioleiomyomatosis (LAM), there are estrogen and progesterone receptors. Therefore, anti-hormonal therapy, despite having produced controversial results, can be considered a treatment option. The objective of this retrospective study was to evaluate hormonal and spirometric data for nine women with LAM after one year of treatment with goserelin. The mean increase in FEV1 and FVC was 80 mL and 130 mL, respectively. There was effective blockage of the hormonal axis. It is still not possible to exclude a potential beneficial effect of the use of gonadotropin-releasing hormone analogues in LAM patients, which underscores the need for randomized trials
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- 2011
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32. Comparison between laparoscopic and subcostal mini-incision for live donor nephrectomy
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Hideki Kanashiro, Roberto Iglesias Lopes, Fernando Akira Saito, Anuar Ibrahim Mitre, Francisco Tibor Denes, José Luis Chambô, Renato Falci Jr, Affonso Celso Piovesan, Elias David Neto, and William Carlos Nahas
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Kidney ,Nephrectomy ,Laparoscopy ,Kidney transplantation ,Tissue donors ,Medicine - Abstract
ABSTRACT Objectives: The aim of this study was to compare the results of laparoscopic donor nephrectomy with open donor nephrectomy. Methods: A non-randomized prospective analysis was conducted of living donor kidney transplantations (118 open donor nephrectomies; 57 laparoscopic donor nephrectomies) between January 2005 and December 2007 in the Kidney Transplantation Unit of Hospital das Clínicas of Faculdade de Medicina of the Universidade de São Paulo. Results: Mean donor operative time, mean donor hospital stay, mean postoperative creatinine values, and rates of complications and graft survival were similar for both groups. A significant statistical difference in warm ischemia time was observed between the open donor nephrectomy and laparoscopic donor nephrectomy groups (p < 0.001). There was only one conversion in the laparoscopic donor nephrectomy group. Conclusions: Laparoscopic donor nephrectomy is a safe procedure for a donor nephrectomy, comparable to an open procedure with similar results despite a longer warm ischemia time.
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- 2010
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33. Robust Step Counting for Inertial Navigation with Mobile Phones
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Germán Rodríguez, Fernando E. Casado, Roberto Iglesias, Carlos V. Regueiro, and Adrián Nieto
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indoor-positioning ,pedestrian dead reckoning ,sensor fusion ,step counting ,Chemical technology ,TP1-1185 - Abstract
Mobile phones are increasingly used for purposes that have nothing to do with phone calls or simple data transfers, and one such use is indoor inertial navigation. Nevertheless, the development of a standalone application able to detect the displacement of the user starting only from the data provided by the most common inertial sensors in the mobile phones (accelerometer, gyroscope and magnetometer), is a complex task. This complexity lies in the hardware disparity, noise on data, and mostly the many movements that the mobile phone can experience and which have nothing to do with the physical displacement of the owner. In our case, we describe a proposal, which, after using quaternions and a Kalman filter to project the sensors readings into an Earth Centered inertial reference system, combines a classic Peak-valley detector with an ensemble of SVMs (Support Vector Machines) and a standard deviation based classifier. Our proposal is able to identify and filter out those segments of signal that do not correspond to the behavior of “walking”, and thus achieve a robust detection of the physical displacement and counting of steps. We have performed an extensive experimental validation of our proposal using a dataset with 140 records obtained from 75 different people who were not connected to this research.
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- 2018
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34. Remote Sensing of Coral Bleaching Using Temperature and Light: Progress towards an Operational Algorithm
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William Skirving, Susana Enríquez, John D. Hedley, Sophie Dove, C. Mark Eakin, Robert A. B. Mason, Jacqueline L. De La Cour, Gang Liu, Ove Hoegh-Guldberg, Alan E. Strong, Peter J. Mumby, and Roberto Iglesias-Prieto
- Subjects
coral bleaching ,Light Stress Damage ,LSD ,DHW ,remote sensing of coral bleaching ,NOAA Coral Reef Watch ,CRW ,mass coral bleaching ,light stress ,Fv/Fm ,Science - Abstract
The National Oceanic and Atmospheric Administration’s Coral Reef Watch program developed and operates several global satellite products to monitor bleaching-level heat stress. While these products have a proven ability to predict the onset of most mass coral bleaching events, they occasionally miss events; inaccurately predict the severity of some mass coral bleaching events; or report false alarms. These products are based solely on temperature and yet coral bleaching is known to result from both temperature and light stress. This study presents a novel methodology (still under development), which combines temperature and light into a single measure of stress to predict the onset and severity of mass coral bleaching. We describe here the biological basis of the Light Stress Damage (LSD) algorithm under development. Then by using empirical relationships derived in separate experiments conducted in mesocosm facilities in the Mexican Caribbean we parameterize the LSD algorithm and demonstrate that it is able to describe three past bleaching events from the Great Barrier Reef (GBR). For this limited example, the LSD algorithm was able to better predict differences in the severity of the three past GBR bleaching events, quantifying the contribution of light to reduce or exacerbate the impact of heat stress. The new Light Stress Damage algorithm we present here is potentially a significant step forward in the evolution of satellite-based bleaching products.
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- 2017
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35. CINCO AÑOS DE EXPERIENCIA CON MALLA SUBURETRAL RETROPUBIANA UBRE DE TENSIÓN EN EL MANEJO DE LA INCONTINENCIA URINARIA DE ESFUERZO EN EL HOSPITAL REGIONAL DE VALDIVIA
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Humberto HottA, Roberto Iglesias R, Emil Schneider B, Claudia Nannig P, Carola Villanueva M, and Gonzalo Valdevenito A
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Incontinencia urinaria de esfuerzo ,malla suburetral ,Stress urinary incontinence ,tension-free vaginal tape ,Gynecology and obstetrics ,RG1-991 - Abstract
Antecedentes: La incontinencia de orina de esfuerzo (IOE) es una patología ginecológica de consulta frecuente, por lo que es importante el enfrentamiento de esta para obtener resultados efectivos a corto y largo plazo. Objetivo: Presentar la experiencia de 5 años en la corrección de la IOE con la técnica quirúrgica de malla de prolene suburetral libre de tensión retropubiana en el servicio de Ginecología del Hospital Regional de Valdivia. Método: Se incluyen pacientes con IOE moderada y severa, primaria o recidivada, estudiadas con hidrodinamia. Se insertó malla suburetral, con revisión posterior de la vejiga por cistoscopia para descartar lesión vesical. La sonda Foley se mantuvo por 24 horas. Resultados: Se intervinieron 58 pacientes con edad promedio de 51 años (rango: 36-76 años), en 48 pacientes se asoció otra cirugía (histerectomía y plastia anterior y/o posterior). No hubo complicaciones en el intraoperatorio. Logramos un seguimiento en 55 pacientes (94,8%) y 3 (5,2%) se perdieron de control. Cincuenta pacientes se encuentran sin IOE (90,9%), con una media de seguimiento de 24 meses (rango: 4-50 meses). Cuarenta y dos pacientes se encuentran actualmente asintomáticas (85,5%) y 8 (14,5%) presentan vejiga hiperactiva en el seguimiento. Conclusión: La técnica de malla suburetral libre de tensión retropubiana es una alternativa eficaz a corto y a largo plazo en el enfrentamiento quirúrgico de la IOE, permitiendo realizar otra cirugía vaginal simultáneamenteBackground: The stress urinary incontinence is a frequent gynecologic problem, therefore the importance of the management to get asymptomatic patients at short and long-term follow up. Objective: The purpose of our study is to show our five years experience with retropubic tension-free vaginal tape. Study design: Fifty eight patients with moderate to severe urinary incontinence were surgically treated at Valdivia Regional Hospital. A careful anamnesis, physical examination and hydrodynamic study were performed before surgery in all patients. A retropubic suburethral tension free vaginal tape was adjusted. The Foley catheter was used for 24 hours after surgery, and postoperative cystoscopy was performed to discard bladder perforations. The patients median age was 51 years (36-76 years). In 48 patients a second surgery was performed (vaginal hysterectomy and anterior or posterior vaginal plasty). Results: Fifty five (94.8%) patients had a mean follow up of 24 months (range: 4-50 months) and three (5.2%) were lost of follow up. Fifty patients (90.9%) turn-up continent. Forty two patientes (85.5%) are actually asymptomatic and eight (14.5%) remain with overactive bladder. Conclusion: The retropubic tension-free vaginal tape is an effective technique in the treatment of urinary stress incontinence, allowing also to perform other vaginal surgery at the same time
- Published
- 2007
36. REPARACIÓN DE PROLAPSO VAGINAL ANTERIOR CON MALLA DE PROLENE
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Humberto Hott A, Roberto Iglesias R, Emil Schneider B, Denisse Anrique Ch, Carola Villanueva M, and Gonzalo Valdevenito A
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Prolapso vaginal anterior ,malla de prolene ,cistocele ,Anterior vaginal prolapse ,prolene mesh ,cysthocele ,Gynecology and obstetrics ,RG1-991 - Abstract
Antecedentes: La reparación del prolapso vaginal anterior presenta una alta tasa de recurrencia. La colporrafia anterior con malla de prolene es una buena alternativa quirúrgica que ha obtenido buenos resultados a largo plazo. Objetivo: Evaluar el resultado anatómico y la evolución de la colporrafia anterior con malla de prolene. Método: Estudio de cohorte prospectivo para evaluar el resultado quirúrgico. Resultados: Ingresaron 35 pacientes con una edad promedio de 61,4 años; 85,7% de ellas estaba en postmenopausia y 3% utilizaba terapia hormonal de reemplazo. La principal patología asociada fue la incontinencia de orina de esfuerzo (54,3%). El estado del piso pelviano preoperatorio correspondió a 31,4% cistocele grado II, 48,6% cistocele grado III y 20% cistocele grado IV. Se asoció prolapso uterino en 88,6% de los casos y 74,3% con prolapso de la pared posterior. No hubo complicaciones intraoperatorias. Hubo complicaciones postoperatorias en 4 pacientes (11,4%). Una paciente presentó erosión de la malla (2,9%). El seguimiento fue de 1 a 11 meses. En la evaluación postoperatoria de las pacientes con cistocele grado II 80% corrigió a grado 0; para cistocele grado III 72% corrigió a grado 0. Un 11% llegó a grado I y 17% grado II. Para el grupo con cistocele grado IV, 71% resultó en grado 0 y 29% grado II. Conclusión: La técnica presentada solucionó un severo problema de calidad de vida de las pacientes afectadas. Se requiere un mayor número de casos y tiempo de seguimiento para su recomendación definitivaBackground: Repair of anterior vaginal prolapse present a high rate of recurrence. Anterior colporrhaphy plus prolene mesh is a surgical option with optimal long term results. Objective: To evaluate anatomical results and evolution of anterior colporrhaphy with prolene mesh. Method: A prospective cohort study was made to evaluate the surgical outcomes. Results: 35 patients were recruited with a median age of 61.4 years. 85.7% of them were in postmenopausal status and 3% were using hormone replacement therapy. Stress urinary incontinence was associated in 54.3% of the cases. The pelvic floor stage at entry was 31.4% cysthocele stage II, 48.6% stage III and 20% cysthocele stage IV. Uterine prolapse was present in 88.6% of cases and the posterior wall was compromised in 74.3%. There were no intraoperatory complications. Postoperatory complications occurred in 4 patients (11.4%). Only in one case the mesh eroded (2.9%). The follow up was from 1 to 11 months. Of the patients with cysthocele stage II at the moment of evaluation, 80% were at stage 0. For cysthocele stage III 72% turned to stage 0. 11% turned to stage I and 17% to stage II. The cases that presented cysthocele stage IV 71% were at stage 0 and 29% at stage II. Conclusion: This technique solved an important quality of life problem of the affected patients. A higher number of cases and time of follow up is needed to recommend this technique definitely
- Published
- 2007
37. Effects of 1997-1998 ENSO on coral reef communities in the Gulf of Califoria, Mexico
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Roberto Iglesias Prieto, Héctor Reyes Bonilla, and Rafael Riosmena Rodríguez
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enso ,estrés térmico ,blanqueamiento de coral ,mortalidad de coral ,zooxantelas ,camas de rodolitos ,Geophysics. Cosmic physics ,QC801-809 - Abstract
Las temperaturas superficiales del océano se incrementan significativamente en la zona del Pacífico este durante los eventos El Niño-Oscilación del Sur (ENSO). Este incremento en las temperaturas afecta negativamente a dos comunidades coralinas de la parte sur del Golfo de California. Durante el evento ENSO de 1997-1998, las comunidades bentónicas sésiles estuvieron expuestas a anomalías térmicas de hasta 3.0 °C. El análisis de los cambios en la cobertura de coral vivo en el área durante 1996 (condición pre- ENSO), 1997, 1998 y 1999, indican que aproximadamente el 30% de los corales padeció blanqueamiento. Este evento de blanqueamiento de coral estuvo acompañado de severas mortalidades de hasta 60%. El blanqueamiento de coral fue más intenso en las regiones localizadas más al norte de la zona en estudio, que en las zonas al sur, las cuales comúnmente están expuestas a temperaturas superiores. Los corales localizados en las partes someras experimentaron una mayor incidencia de blanqueamiento que aquéllos localizados en aguas profundas. Los análisis fisiológicos indican que esta distribución vertical responde a diferencias en la temperatura y no a diferencias en la iluminación. Junto con el blanqueamiento y la mortalidad de coral, detectamos variaciones en las densidades poblacionales y en la distribución de tallas de algunos invertebrados asociados al coral. El análisis de las variaciones anuales en riqueza específica de las algas asociadas a los mantos de rodolitos, permiten trazar una línea de base para estudios futuros sobre los impactos del ENSO en estos ecosistemas. doi: https://doi.org/10.22201/igeof.00167169p.2003.42.3.935
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- 2003
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38. Effects of 1997-1998 ENSO on coral reef communities in the Gulf of California, Mexico
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Rafael Riosmena Rodríguez, Héctor Reyes Bonilla, and Roberto Iglesias Prieto
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ENSO ,thermal stress ,coral bleaching ,coral mortality ,Zooxanthella ,rodolith beds. ,Geophysics. Cosmic physics ,QC801-809 - Abstract
Sea surface temperatures in the eastern tropical Pacific increase dramatically during El Niño Southern Oscillation (ENSO) events. This increase in sea temperature negatively affects two important coralline communities in the southern Gulf of California. During the 1997-1998 ENSO event, benthic sessile communities were exposed to a thermal anomaly of up to 3 °C during the summer. About 30% of live corals in six important communities in the region during 1996 (pre-ENSO conditions), 1997, 1998 and 1999 experienced coral bleaching, accompanied by 60% mortality. Coral bleaching was more intense close to the northern part of the studied area, as the southern area is normally exposed to higher temperatures. Corals located in shallow water experienced a higher incidence of bleaching than in deeper areas. This pattern is a response to temperature stratification and not to differences in light conditions. We detected variations in the densities and size distributions of the coral-associated fauna associated with coral bleaching and mortality. Annual variations in species abundance of the algal community associated with rodolith beds during 1998-2000 should provide us baseline information to assess the effects of future ENSO events on the rodolith community.
- Published
- 2003
39. Efecto del extracto hipoglicemiante de Petiveria alliacea L sobre el consumo de glucosa por los eritrocitos
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Delia Rojo Domínguez, Luis Bell Heredia, Elena Cancio Martínez, and Roberto Iglesias Lores
- Subjects
PLANTAS MEDICINALES ,EXTRACTOS VEGETALES ,ERITROCITOS ,DIABETES MELLITUS ,AGENTES HIPOGLUCEMICOS ,PLANTS, MEDICINAL ,PLANT, EXTRACTS ,ERYTHROCITES ,HYPOGLYCEMIC AGENTS ,Medicine (General) ,R5-920 - Abstract
Se estudió el efecto de un extracto hipoglicemiante de Petiveria alliacea L sobre el consumo de glucosa por los eritrocitos de donantes voluntarios sanos. Los eritrocitos se incubaron con una dilución de sheilina de 1 UD/10 mL durante 4 h y se determinó la concentración de glucosa a los tiempos 0, 30, 60, 90, 120, 150, 180, 210 y 240 min. Para determinar si había efecto dosis respuesta se incubaron los eritrocitos con dosis crecientes de sheilina (0, 0,5, 1, 5, 10 y 15 U/10 mL). Se obtuvo que la sheilina no afecta el consumo de glucosa por los eritrocitos ni a dosis elevadas. Estos resultados sugieren que la acción del producto no afecta el transportador de glucosa (glut 1) ni la fase anaerobia de la glicólisis, por lo que su acción hipoglicemiante parece estar ligada a la acción de la insulina.The effect of a hypoglycemic extract of Petiveria alleacea L on glucose consumption was studied by using the erythrocytes of voluntary healthy donors. The erythrocytes were incubated with a dilution of sheilina of 1 UD/10 mL during 4 hours and the glucose concentration was determined at 0, 30, 60, 90, 120, 150, 180, 210 and 240 min. To determine the existance of a dose response effect, the erythrocytes were incubated with increasing doses of sheilina (0, 0.5, 1, 5, 10 and 15 U/10 mL) It was observed that even at elevated doses sheilina does not affect the consumption of glucose by the erythrocytes. These results suggest that the action of the product affects neither the glucose tansporter (glut 1) nor the anaerobic phase of glycosis. That’s why its hypoglycemic action seems to be connected with insulin action.
- Published
- 2002
40. Symbiodinium photosynthesis in Caribbean octocorals.
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Blake D Ramsby, Kartick P Shirur, Roberto Iglesias-Prieto, and Tamar L Goulet
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Medicine ,Science - Abstract
Symbioses with the dinoflagellate Symbiodinium form the foundation of tropical coral reef communities. Symbiodinium photosynthesis fuels the growth of an array of marine invertebrates, including cnidarians such as scleractinian corals and octocorals (e.g., gorgonian and soft corals). Studies examining the symbioses between Caribbean gorgonian corals and Symbiodinium are sparse, even though gorgonian corals blanket the landscape of Caribbean coral reefs. The objective of this study was to compare photosynthetic characteristics of Symbiodinium in four common Caribbean gorgonian species: Pterogorgia anceps, Eunicea tourneforti, Pseudoplexaura porosa, and Pseudoplexaura wagenaari. Symbiodinium associated with these four species exhibited differences in Symbiodinium density, chlorophyll a per cell, light absorption by chlorophyll a, and rates of photosynthetic oxygen production. The two Pseudoplexaura species had higher Symbiodinium densities and chlorophyll a per Symbiodinium cell but lower chlorophyll a specific absorption compared to P. anceps and E. tourneforti. Consequently, P. porosa and P. wagenaari had the highest average photosynthetic rates per cm2 but the lowest average photosynthetic rates per Symbiodinium cell or chlorophyll a. With the exception of Symbiodinium from E. tourneforti, isolated Symbiodinium did not photosynthesize at the same rate as Symbiodinium in hospite. Differences in Symbiodinium photosynthetic performance could not be attributed to Symbiodinium type. All P. anceps (n = 9) and P. wagenaari (n = 6) colonies, in addition to one E. tourneforti and three P. porosa colonies, associated with Symbiodinium type B1. The B1 Symbiodinium from these four gorgonian species did not cluster with lineages of B1 Symbiodinium from scleractinian corals. The remaining eight E. tourneforti colonies harbored Symbiodinium type B1L, while six P. porosa colonies harbored type B1i. Understanding the symbioses between gorgonian corals and Symbiodinium will aid in deciphering why gorgonian corals dominate many Caribbean reefs.
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- 2014
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41. Pediatric Genitourinary Oncology
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Francisco Tibor Dénes, Ricardo Jordão Duarte, Lilian Maria Cristofani, and Roberto Iglesias Lopes
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Kidney Neoplasms ,Rhabdomyosarcoma ,Testicular Neoplasms ,adrenal tumors ,pediatric tumor ,Pediatrics ,RJ1-570 - Abstract
Tumours of kidney, bladder, prostate, testis and adrenal represent a large part of the adult urologic practice, but are relatively infrequent in children. The natural history and management of these tumours in the pediatric age is different from that of adults. As result of the successful work of several clinical trial groups in recent decades, there has been a significant improvement in their cure rates. The aim of this article is to review their most significant clinical aspects, as well as to present an update in their management.
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- 2013
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42. Vesico-appendiceal fistula in a mucinous adenocarcinoma of the appendix Fístula vésico-apendicular em adenocarcinoma mucinoso do apêndice
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Ivan R B Orso, Rodrigo Ambar Pinto, Marcus FKP Ramos, Desidério Roberto Kiss, Roberto Iglesias Lopes, Marcello Cocuzza, and José Luis Borges de Mesquita
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Câncer do apêndice ,Fístula urinária ,Quimioterapia adjuvante ,Hipertermia terapêutica ,Appendiceal cancer ,Urinary bladder fistula ,Adjuvant chemotherapy ,Therapeutic hyperthermia ,Surgery ,RD1-811 ,Diseases of the digestive system. Gastroenterology ,RC799-869 - Abstract
BACKGOUND: A rare case of vesicoappendiceal fistula secondary to mucinous adenocarcinoma of the appendix is presented. CASE REPORT: A 62-year-old man with a one year history of recurrent urinary tract infections. After two months he developed pneumaturia and fecaluria. An abdominal and pelvic computed tomography demonstrated a trans-mural mass in the posterior wall of the bladder with a vesicoenteric fistula leading to the terminal ileum. Laparotomy revealed a tumor arising from the appendix contiguous with the bladder posterior wall. The bladder was opened and a large fistula and tumor on the posterior bladder wall near the trigone was identified. Frozen pathological analysis showed a mucinous adenocarcinoma. En-bloc right hemicolectomy and partial cystectomy, preserving bladder trigone was performed. After manipulating the tumor, grossly leakage of mucinous materials occurred into the pelvic cavity. A peritoneal washing with a mytomicin solution at 42º C was then performed, to prevent peritoneal seeding. The patient had a prolonged postoperative ileus and was discharged at the 15th day. Five months after the procedure the patient was recieving chemotherapy with 5-fluoracil and leucovorin and there was no signs of recurrent disease. CONCLUSION: The presentation with vesico-appendiceal fistula is extremely rare with only a few cases reported in the literature. Knowledge of different types of neoplasm and appropriate treatment allows the surgeon to provide patients optimal care referring to specialized centers whenever appropriate.INTRODUÇÃO: Apresenta-se raro caso de fístula vésico-apendicular secundária a adenocarcinoma mucinoso do apêndice. RELATO DE CASO: Paciente masculino de 62 anos com história de um ano de infecções urinárias de repetição. Após dois meses desenvolveu pneumatúria e fecalúria, sendo indicada tomografia computadorizada de abdômen que mostrou massa trans-mural na parede da bexiga, com fistula vésico-entérica para região do íleo terminal. A laparotomia revelou tumoração surgindo do apêndice cecal, em continuidade com a parede posterior da bexiga. A mesma foi aberta, sendo identificada grande fistula e material tumoral até próximo ao trígono vesical. A biópsia de congelação identificou adenocarcinoma mucinoso. Realizada hemicolectomia associada à cistectomia parcial em bloco, com preservação do trígono vesical. Houve extravasamento de mucina para a cavidade pélvica pela manipulação. Optado por lavagem peritoneal com solução de mitomicina a 42º C para prevenir disseminação peritoneal. O paciente evoluiu com íleo prolongado pós-operatório, tendo alta hospitalar no15º dia. Cinco meses após o procedimento encontrava-se em quimioterapia com 5-fluouracil e leucovorin, sem sinais de doença recidivante. CONCLUSÃO: A presença de fístula vésico-apendicecal é extremamente rara, tendo poucos casos relatados na literatura. O conhecimento dos diferentes tipos de neoplasias e seus tratamentos adequados permite ao cirurgião oferecer melhor cuidado ao paciente.
- Published
- 2008
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43. Benthic primary production budget of a Caribbean reef lagoon (Puerto Morelos, Mexico).
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Malik S Naumann, Carin Jantzen, Andreas F Haas, Roberto Iglesias-Prieto, and Christian Wild
- Subjects
Medicine ,Science - Abstract
High photosynthetic benthic primary production (P) represents a key ecosystem service provided by tropical coral reef systems. However, benthic P budgets of specific ecosystem compartments such as macrophyte-dominated reef lagoons are still scarce. To address this, we quantified individual and lagoon-wide net (Pn) and gross (Pg) primary production by all dominant functional groups of benthic primary producers in a typical macrophyte-dominated Caribbean reef lagoon near Puerto Morelos (Mexico) via measurement of O₂ fluxes in incubation experiments. The photosynthetically active 3D lagoon surface area was quantified using conversion factors to allow extrapolation to lagoon-wide P budgets. Findings revealed that lagoon 2D benthic cover was primarily composed of sand-associated microphytobenthos (40%), seagrasses (29%) and macroalgae (27%), while seagrasses dominated the lagoon 3D surface area (84%). Individual Pg was highest for macroalgae and scleractinian corals (87 and 86 mmol O₂ m(-2) specimen area d(-1), respectively), however seagrasses contributed highest (59%) to the lagoon-wide Pg. Macroalgae exhibited highest individual Pn rates, but seagrasses generated the largest fraction (51%) of lagoon-wide Pn. Individual R was highest for scleractinian corals and macroalgae, whereas seagrasses again provided the major lagoon-wide share (68%). These findings characterise the investigated lagoon as a net autotrophic coral reef ecosystem compartment revealing similar P compared to other macrophyte-dominated coastal environments such as seagrass meadows and macroalgae beds. Further, high lagoon-wide P (Pg: 488 and Pn: 181 mmol O₂ m(-2) lagoon area d(-1)) and overall Pg:R (1.6) indicate substantial benthic excess production within the Puerto Morelos reef lagoon and suggest the export of newly synthesised organic matter to surrounding ecosystems.
- Published
- 2013
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44. Induction of glycerol synthesis and release in cultured Symbiodinium.
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Luis P Suescún-Bolívar, Roberto Iglesias-Prieto, and Patricia E Thomé
- Subjects
Medicine ,Science - Abstract
Symbiotic dinoflagellates transfer a substantial amount of their photosynthetic products to their animal hosts. This amount has been estimated to represent up to 90% of the photosynthetically fixed carbon and can satisfy in some instances the full respiratory requirements of the host. Although in several cnidarian-dinoflagellate symbioses glycerol is the primary photosynthetic product translocated to the host, the mechanism for its production and release has not been demonstrated conclusively.Using Symbiodinium cells in culture we were able to reproduce the synthesis and release of glycerol in vitro by employing an inductor for glycerol synthesis, osmotic up-shocks. Photosynthetic parameters and fluorescence analysis of photosystem II showed that the inductive conditions did not have a negative effect on photosynthetic performance, suggesting that the capacity for carbon fixation by the cells was not compromised. The demand for glycerol production required to attain osmotic balance increased the expression of ribulose 1,5-bisphosphate and of glycerol 3-phosphate dehydrogenase, possibly competing with the flux of fixed carbon necessary for protein synthesis. In longer exposures of cultured Symbiodinium cells to high osmolarity, the response was analogous to photoacclimation, reducing the excitation pressure over photosystem II, suggesting that Symbiodinium cells perceived the stress as an increase in light. The induced synthesis of glycerol resulted in a reduction of growth rates.Our results favor a hypothetical mechanism of a signaling event involving a pressure sensor that may induce the flux of carbon (glycerol) from the symbiotic algae to the animal host, and strongly suggest that carbon limitation may be a key factor modulating the population of symbionts within the host.
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- 2012
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45. A connection between colony biomass and death in Caribbean reef-building corals.
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Daniel J Thornhill, Randi D Rotjan, Brian D Todd, Geoff C Chilcoat, Roberto Iglesias-Prieto, Dustin W Kemp, Todd C LaJeunesse, Jennifer McCabe Reynolds, Gregory W Schmidt, Thomas Shannon, Mark E Warner, and William K Fitt
- Subjects
Medicine ,Science - Abstract
Increased sea-surface temperatures linked to warming climate threaten coral reef ecosystems globally. To better understand how corals and their endosymbiotic dinoflagellates (Symbiodinium spp.) respond to environmental change, tissue biomass and Symbiodinium density of seven coral species were measured on various reefs approximately every four months for up to thirteen years in the Upper Florida Keys, United States (1994-2007), eleven years in the Exuma Cays, Bahamas (1995-2006), and four years in Puerto Morelos, Mexico (2003-2007). For six out of seven coral species, tissue biomass correlated with Symbiodinium density. Within a particular coral species, tissue biomasses and Symbiodinium densities varied regionally according to the following trends: Mexico≥Florida Keys≥Bahamas. Average tissue biomasses and symbiont cell densities were generally higher in shallow habitats (1-4 m) compared to deeper-dwelling conspecifics (12-15 m). Most colonies that were sampled displayed seasonal fluctuations in biomass and endosymbiont density related to annual temperature variations. During the bleaching episodes of 1998 and 2005, five out of seven species that were exposed to unusually high temperatures exhibited significant decreases in symbiotic algae that, in certain cases, preceded further decreases in tissue biomass. Following bleaching, Montastraea spp. colonies with low relative biomass levels died, whereas colonies with higher biomass levels survived. Bleaching- or disease-associated mortality was also observed in Acropora cervicornis colonies; compared to A. palmata, all A. cervicornis colonies experienced low biomass values. Such patterns suggest that Montastraea spp. and possibly other coral species with relatively low biomass experience increased susceptibility to death following bleaching or other stressors than do conspecifics with higher tissue biomass levels.
- Published
- 2011
- Full Text
- View/download PDF
46. Impuestos para el control del tabaquismo: las experiencias de Brasil y México Taxation and tobacco control: the cases of Brazil and Mexico
- Author
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Belén Sáenz de Miera-Juárez and Roberto Iglesias
- Subjects
tabaco ,impuestos ,elasticidad ,Brasil ,México ,tobacco ,taxes ,elasticity ,Brazil ,Mexico ,Public aspects of medicine ,RA1-1270 - Abstract
Este trabajo pretende analizar los avances, obstáculos y retos en materia de impuestos a los cigarrillos en Brasil y México. En años recientes ambos países han incrementado estos impuestos y han incorporado alícuotas fijas, lo cual permite maximizar el efecto del aumento de los impuestos sobre los precios. Sin embargo, parece que estas medidas no se han aprovechado en toda su potencialidad. Tres recomendaciones surgen de estas experiencias: 1) las alícuotas fijas deben representar un porcentaje significativo del precio final; 2) deben ajustarse regularmente de acuerdo con la inflación acumulada; y 3) deben ajustarse para compensar el crecimiento del ingreso personal. También es importante que los impuestos a los sustitutos legales sean similares a los de los cigarrillos. En el caso de los sustitutos ilegales, la cuestión es reducir los incentivos y limitar la facilidad con que se realiza su distribución y venta. Adecuaciones en las legislaciones nacionales y cooperación internacional constituyen elementos clave para lograrlo.This study analyzes the achievements, obstacles and challenges related to cigarette taxes in Brazil and Mexico. Both countries have increased cigarette taxes in recent years and have included a specific tax, which allows maximizing the impact of tax increases on prices. However, it seems they have not taken full advantage of these measures. Three recommendations follow from these experiences: 1) specific taxes must represent a significant percentage of final prices; 2) specific taxes must be regularly adjusted to keep pace with cumulative inflation; and 3) specific taxes must be adjusted to compensate increases in personal income. It is also important to consider that taxes on legal substitutes of cigarettes must be similar to cigarette taxes. As for illegal substitutes, the issue is to reduce the incentives for illicit trade and to make illegal transactions more difficult. Modifications to national legislations and international cooperation constitute key elements to achieve this.
- Published
- 2010
47. Task Characterisation and Cross-Platform Programming Through System Identification
- Author
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Roberto Iglesias, Urlich Nehmzow, Theocharis Kyriacou, and Steve Billings
- Subjects
Electronics ,TK7800-8360 ,Electronic computers. Computer science ,QA75.5-76.95 - Abstract
Developing robust and reliable control code for autonomous mobile robots is difficult, because the interaction between a physical robot and the environment is highly complex, it is subject to noise and variation, and therefore partly unpredictable. This means that to date it is not possible to predict robot behaviour, based on theoretical models. Instead, current methods to develop robot control code still require a substantial trial-and-error component to the software design process. Such iterative refinement could be reduced, we argue, if a more profound theoretical understanding of robot-environment interaction existed. In this paper, we therefore present a modelling method that generates a faithful model of a robot's interaction with its environment, based on data logged while observing a physical robot's behaviour. Because this modelling method - nonlinear modelling using polynomials - is commonly used in the engineering discipline of system identification, we refer to it here as "robot identification". We show in this paper that using robot identification to obtain a computer model of robot environment interaction offers several distinct advantages: 1. Very compact representations (one-line programs) of the robot control program are generated 2.The model can be analysed, for example through sensitivity analysis, leading to a better understanding of the essential parameters underlying the robot's behaviour, and 3. The generated, compact robot code can be used for cross-platform robot programming, allowing fast transfer of robot code from one type of robot to another. We demonstrate these points through experiments with a Magellan Pro and a Nomad 200 mobile robot.
- Published
- 2008
48. Task Characterisation and Cross-Platform Programming Through System Identification
- Author
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Theocharis Kyriacou, Ulrich Nehmzow, Roberto Iglesias, and Steve Billings
- Subjects
Electronics ,TK7800-8360 ,Electronic computers. Computer science ,QA75.5-76.95 - Abstract
Developing robust and reliable control code for autonomous mobile robots is difficult, because the interaction between a physical robot and the environment is highly complex, it is subject to noise and variation, and therefore partly unpredictable. This means that to date it is not possible to predict robot behaviour, based on theoretical models. Instead, current methods to develop robot control code still require a substantial trial-and-error component to the software design process. Such iterative refinement could be reduced, we argue, if a more profound theoretical understanding of robot-environment interaction existed. In this paper, we therefore present a modelling method that generates a faithful model of a robot's interaction with its environment, based on data logged while observing a physical robot's behaviour. Because this modelling method — nonlinear modelling using polynomials — is commonly used in the engineering discipline of system identification, we refer to it here as “robot identification”. We show in this paper that using robot identification to obtain a computer model of robot-environment interaction offers several distinct advantages: Very compact representations (one-line programs) of the robot control program are generated The model can be analysed, for example through sensitivity analysis, leading to a better understanding of the essential parameters underlying the robot's behaviour, and The generated, compact robot code can be used for cross-platform robot programming, allowing fast transfer of robot code from one type of robot to another. We demonstrate these points through experiments with a Magellan Pro and a Nomad 200 mobile robot.
- Published
- 2005
- Full Text
- View/download PDF
49. Influence of low free thyroxine on progression of chronic kidney disease
- Author
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de Souza, Alexandre Barbosa Câmara, Arantes, Marcia Fernanda, Zatz, Roberto, Elias, Rosilene Motta, Lopes, Roberto Iglesias, and Macedo, Etienne
- Subjects
Biomedical and Clinical Sciences ,Clinical Sciences ,Kidney Disease ,Clinical Research ,Renal and urogenital ,Metabolic and endocrine ,Aged ,Aged ,80 and over ,Disease Progression ,Female ,Follow-Up Studies ,Glomerular Filtration Rate ,Humans ,Hypothyroidism ,Male ,Middle Aged ,Proteinuria ,Renal Insufficiency ,Chronic ,Thyroxine ,Urology & Nephrology ,Clinical sciences ,Health services and systems ,Nursing - Abstract
BackgroundHypothyroidism is highly prevalent in patients with chronic kidney disease (CKD) and has been associated with poorer clinical outcomes, including faster decline of kidney function. However, there is no consensus whether low free thyroxin (LFT) affects the rate of estimated glomerular filtration rate (eGFR) decline and how the presence of proteinuria influences the progression of renal dysfunction in hypothyroidism.MethodsWe assessed thyroid status, proteinuria, and progression of eGFR by Modification of Diet in Renal Disease equation and CKD-EPI equation in a cohort of CKD patients followed in general nephrology clinics. We estimated the association of LFT levels, and the degree of proteinuria on progression of eGFR. We adjusted for other covariables: age, gender, body mass index, diabetes, hypertension, HbA1c, uric acid, cholesterol, and triglycerides levels..ResultsOne thousand six hundred ten patients (64 ± 15 years, 46.8% men, 25.3% diabetic) were included. At beggnining of follow up eGFR was between 45 and 60, 30-45 and 15-30 ml/min/1.73m2 in 479 (29.8%), 551(34.2%), and 580(36.0%) patients, respectively. LFT levels were available at initial evaluation in 288(17.9%) patients and 735(48.5%) had assessment of proteinuria (19.6% with LFT vs. 15.4% without LFT, p = 0.032). Median follow-up time was of 21 months, and 1223(76%) had at least 1 year of follow up. Overall, eGFR decline per month was - 0.05(- 0.26, 0.23) ml/min/1.73m2, reaching 1.7(1.3, 2.4) ml/min/1.73m2 by the end of study period. Similar results were obtained using CKD-EPI. Multivariable mixed linear analysis showed that proteinuria and age were independently associated with eGFR decline, with no effect of LFT, and no interaction between proteinuria and LFT. In patients without proteinuria, there was an improvement of eGFR despite the presence of LFT.ConclusionsWe confirmed a faster rate of eGFR declined in patients with proteinuria. However, despite the pathophysiological rational that hypothyroidism can lead to increased rate of CKD progression, we failed to demonstrate an association between LFT and rate of CKD progression. We conclude that the benefit of hypothyroidism treatment in CKD patients needs to be evaluate in prospective studies.
- Published
- 2020
50. Bilateral external iliac artery pseudoaneurysms causing urinary obstruction and acute renal failure
- Author
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Bigarella, Marcelo Puppo, Lopes, Roberto Iglesias, Gentile, Guilherme, Faustino, Carolina Brito, da Cunha Gamba, Lais, Lima, Guilherme Baumgardt Barbosa, Melo, Henry Augusto Hoffman, and Mulatti, Grace Carvajal
- Published
- 2022
- Full Text
- View/download PDF
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