4,916 research outputs found

    Overview of Study Areas and UNAM-Iztacala Student Research

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    The State of Veracruz is located on the east coast of Mexico and consists of many shallow marine systems such as estuaries and coastal lagoons. These estuarine systems are ecological sites of great importance due to the interactions that occur between the intertidal zones and adjacent areas. This importance is reflected in the variety of natural components present in these sites as well as the large number of species that depend on this aquatic zone, such as birds, mammals, molluscs, crustaceans and fishes. Many of the crustaceans and fishes are consumed by the local inhabitants and distributed in commercial areas in Mexico City. It is estimated that Veracruz state is in fourth place in fisheries landings for the country, and contributes 10% of the total fisheries production. Academic personnel from the laboratories of Ecology and Zoology in the Facultad de Estudios Superiores Iztacala, Tlalnapantla, Mexico have focused their research efforts since 1988 on two of the systems in Veracruz state, the Tecolutla River and the lagoonal system of Alvarado. Research in both locations has resulted in a number of professional theses by undergraduate students in the Biology Department at UNAM-Iztacala

    Evaluar las condiciones de higiene y seguridad laboral en el proceso de producción del beneficio AGROEXPORT S.A, del Municipio de Matagalpa durante el I semestre del año 2016

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    En la investigación se analizaron las diferentes medidas de Higiene y Seguridad Laboral aplicada a los trabajadores del Beneficio de frijol AGROEXPORT S.A, al segundo semestre del año 2015. Las variables que se evaluaron fueron las siguientes, Higiene y Seguridad Laboral en el Beneficio de frijol AGROEXPORT S.A, se utilizó el método inductivo y deductivo para la recolección de información, a partir de consultas bibliográficas a libros e internet, así como el empírico haciendo uso de fuentes primarias mediante la aplicación de encuestas, entrevistas y observaciones. Los resultados obtenidos de toda esta labor investigativa se logró identificar con claridad que la empresa tiene constituida la comisión mixta de higiene y seguridad laboral como lo establece la ley 618, (2007) ley de higiene y seguridad del trabajo, por otra parte se pudo constatar que en el área de producción la ventilación no es adecuada. Para el logro de los objetivos trazados y mejoramiento contínuo en materia de seguridad e higiene se deberá elaborar planes ajustados a la realidad de la empresa, así también es necesaria la capacitación continua para que el personal conozca todo lo necesario para mantener un ambiente laboral saludable y segur

    Simulating the behavior of the human brain on GPUS

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    The simulation of the behavior of the Human Brain is one of the most important challenges in computing today. The main problem consists of finding efficient ways to manipulate and compute the huge volume of data that this kind of simulations need, using the current technology. In this sense, this work is focused on one of the main steps of such simulation, which consists of computing the Voltage on neurons’ morphology. This is carried out using the Hines Algorithm and, although this algorithm is the optimum method in terms of number of operations, it is in need of non-trivial modifications to be efficiently parallelized on GPUs. We proposed several optimizations to accelerate this algorithm on GPU-based architectures, exploring the limitations of both, method and architecture, to be able to solve efficiently a high number of Hines systems (neurons). Each of the optimizations are deeply analyzed and described. Two different approaches are studied, one for mono-morphology simulations (batch of neurons with the same shape) and one for multi-morphology simulations (batch of neurons where every neuron has a different shape). In mono-morphology simulations we obtain a good performance using just a single kernel to compute all the neurons. However this turns out to be inefficient on multi-morphology simulations. Unlike the previous scenario, in multi-morphology simulations a much more complex implementation is necessary to obtain a good performance. In this case, we must execute more than one single GPU kernel. In every execution (kernel call) one specific part of the batch of the neurons is solved. These parts can be seen as multiple and independent tridiagonal systems. Although the present paper is focused on the simulation of the behavior of the Human Brain, some of these techniques, in particular those related to the solving of tridiagonal systems, can be also used for multiple oil and gas simulations. Our studies have proven that the optimizations proposed in the present work can achieve high performance on those computations with a high number of neurons, being our GPU implementations about 4× and 8× faster than the OpenMP multicore implementation (16 cores), using one and two NVIDIA K80 GPUs respectively. Also, it is important to highlight that these optimizations can continue scaling, even when dealing with a very high number of neurons.This project has received funding from the European Union’s Horizon 2020 Research and Innovation Programme under Grant Agreement No. 720270 (HBP SGA1), from the Spanish Ministry of Economy and Competitiveness under the project Computación de Altas Prestaciones VII (TIN2015-65316-P), the Departament d’Innovació, Universitats i Empresa de la Generalitat de Catalunya, under project MPEXPAR: Models de Programació i Entorns d’Execució Parallels (2014-SGR-1051). We thank the support of NVIDIA through the BSC/UPC NVIDIA GPU Center of Excellence, and the European Union’s Horizon 2020 Research and Innovation Program under the Marie Sklodowska-Curie Grant Agreement No. 749516.Peer ReviewedPostprint (published version

    Validity of a four-factor modelunderlying the physical fitness in adults with intellectual disabilities a confirmatory factor analysis

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    Purpose: To use confirmatory factor analysis to test whether a four factor might explain the clustering of the components of the physical fitness in adults with intellectual disabilities (FID). Relevance: Individuals with intellectual disabilities (ID) are significantly weaker than individuals without ID at all stages of life. These subjects might be particularly susceptible to loss of basic function because of poor physical fitness. Participants: We studied 267 adults with intellectual disability of the Spanish Special Olympics Games. Methods: The four-factor model included: the flexibility, the strength, the balance and the cardiorespiratory endurance with 9 variables of the fitness assessment. Analysis: The construct validity of the model was assessed through the factor loadings, interpreted as the correlation between the variables in the model and their underlying factor, which is the FID construct. Results: Factor loading were 0,55 for the passive knee extension, o,52 for Functional shoulder rotation, −0.71 for the timed-stand test, 0.58 for the grip test, 0.75 the single leg stance with eyes open, 0.69 single leg stance with eyes closed, 0.72 for the resting heart rate, 0.56 for the two-minute step test (2MST) 0,97 for 2 minutes after finish 2MST. The four-factor model also showed a good fit to the data, as indicated by a high comparative fit index (CFI=0,93) and a low standardized root mean square residual (SRMR=0,072) Conclusions: A four underlying factor has shown acceptable validity to represent FID Implications: The new model of FID can offer understanding better these construct in this special populationUniversidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Reproductive Structures and Early Life History of the Gulf Toadfish, Opsanus beta, in the Tecolutla Estuary, Veracruz, Mexico

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    Although the Gulf toadfish, Opsanus beta, is an abundant member of the nearshore Gulf of Mexico ichthyofaunal assemblage, little information exists regarding the ecology of the species, especially for southern Gulf of Mexico populations. We added to the existing knowledge of this species by describing the reproductive structures and examining the early life history of this species in the Tecolutla estuary, Mexico. Macro- and microscopic examination of 7 males showed spermatogenesis to be similar to other teleost species except for the occurrence of biflagellate spermatozoa. Histological examination of the male accessory gland showed 3 tissue layers, but their functions are still undetermined. We found asynchronous development of oocytes in the ovaries of 16 females, which may indicate multiple spawning over the long spawning season noted in this study. Batch fecundity estimates among females ranged from 79 to 518 mature ova with a mean ovum diameter of 3.5 mm. The above-mentioned factors along with large size at hatching, attached larval forms, and paternal care may account, in part, for the abundance of this species in highly dynamic systems

    Feeding Habits and Sexual Dimorphism of the Violet Goby, Gobioides broussoneti Lacepede (Pisces: Gobiidae), in the Estuarine System of Tecolutla, Veracruz, Mexico

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    Gobioides broussoneti were sampled in Silveña estuary, a branch of the Tecolutla estuary, Veracruz, Mexico, during 2 trips made between February 1998 and June 1999 to evaluate diet and sexual dimorphism. A total of 65 G. broussoneti ranging from 49–401 mm SL (0.7–124.2 g WW) were collected. There was a 1:1.2 sex ratio in favor of females. Seven food types were noted, with filamentous algae (25.4%) and detritus (21.3%) representing the principal food types. A 24 h feeding study revealed that this species feeds continuously throughout the day. The ovaries of all female G. broussoneti contained previtellogenic oocytes, characteristic of immature or regressed fish. In contrast, the lobular testis of the males contained late stages of spermatogenesis, suggesting that the fish examined were at the end of the reproductive season. Sexual dimorphism of G. broussoneti is distinguished by a small urogenital papilla, which is in the ventral region between the anal orifice and the anal fin origin. In the females it is short, blunt and has a yellow coloration; in males it is thin, pointed and has a smooth appearance. Only immature or regressed females were captured during this study indicating that G. broussoneti uses the Tecolutla estuary as a nursery and feeding ground. Questions about reproductive seasonality, ovarian development, and spawning of G. broussoneti need further investigation

    Un caso práctico para la gestión del desarrollo agropecuario en municipios rurales de México

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    Una de las múltiples formas en que se atiende la pobreza en México es a través de la definición y diseño de estrategias de desarrollo enfocadas a mejorar las condiciones de vida de la población rural de escasos recursos económicos y déficit de bienestar social, actuando desde el municipio como articulador del desarrollo.Un texto detonante de preguntas y respuestas sobre la gestión del desarrollo rural y agropecuario desde la esfera municipal, en un esquema de gobernanza sugerente y efectivo, que retoma la experiencia de organizaciones civiles en los años recientes bajo el concepto y caso práctico de Municipio Ganador.Alternativas para el Desarrollo Rura

    Fighting rheumatoid arthritis: Kv1.3 as a therapeutic target

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    Abstract Rheumatoid arthritis (RA) is a serious autoimmune disease that has severe impacts on both the wellbeing of patients and the economy of the health system. Similar to many autoimmune diseases, RA concurs with a long evolution, which eventually results in highly debilitating symptoms. Therapeutic treatments last for long periods during RA. However, their efficiency and side effects result in suboptimal conditions. Therefore, the need for specific, safer and nontoxic alternatives for the treatment of RA is essential. Kv1.3 is a voltage-gated potassium channel that has a crucial role in immune system response. The proliferation and activation of leukocytes are linked to differential expressions of this channel. The evidence is particularly relevant in the aggressive T effector memory (TEM) cells, which are the main actors in the development of autoimmune diseases. Blockage of Kv1.3 inhibits the reactivity of these cells. Furthermore, pharmacological inhibition of Kv1.3 ameliorates symptoms in animal models of autoimmune diseases, such as experimental autoimmune encephalomyelitis or induced psoriasis with no side effects. Kv1.3 is sensitive to several animal toxins and plant compounds, and several research groups have searched for new Kv1.3 blockers by improving these natural molecules. The research is mainly focused on enhancing the selectivity of the blockers, thereby reducing the potential for side effects on other related channel subunits. Higher selectivity means that treatments will potentially be less harmful. This leads to a lower discontinuation rate of the therapy than the current first-line treatment for RA. The molecular backgrounds of many autoimmune diseases implicate leukocyte Kv1.3 and suggests that a new medication for RA is feasible. Therapies could also be later repurposed to treat other immune system disorders
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