Spacelike immersions in certain Lorentzian manifolds with lightlike foliations

The generalized Schwarzschild spacetimes are introduced as warped manifolds where the base is an open subset of $\mathbb{R}^2$ equipped with a Lorentzian metric and the fiber is a Riemannian manifold. This family includes physically relevant spacetimes closely related to models of black holes. The generalized Schwarzschild spacetimes are endowed with involutive distributions which provide foliations by lightlike hypersurfaces. In this paper, we study spacelike submanifolds immersed in the generalized Schwarzschild spacetimes, mainly, under the assumption that such submanifolds lie in a leaf of the above foliations. In this scenario, we provide an explicit formula for the mean curvature vector field and establish relationships between the extrinsic and intrinsic geometry of the submanifolds. We have derived several characterizations of the slices, and we delve into the specific case where the warping function is the radial coordinate in detail. This subfamily includes the Schwarzschild and Reissner-Nordstr\"om spacetimes

M\"{o}bius structures and Weingarten endomorphisms of spacelike submanifolds

Starting from a Riemannian conformal structure on a manifold $M$, we provide a method to construct a family of Lorentzian manifolds. The construction relies on the choice of a metric in the conformal class and a smooth $1$-parameter family of self-adjoint tensor fields and it has been inspired by the Fefferman and Graham ambient metric for conformal structures. Every metric in the conformal class corresponds to the induced metric on a codimension two spacelike submanifold into these Lorentzian manifolds. Under suitable choices of the $1$-parameter family of tensor fields, there exists a lightlike normal vector field along such spacelike submanifolds which Weingarten endomorphisms provide a M\"{o}bius structure on the Riemannian conformal structure. Conversely, every M\"{o}bius structure on a Riemannian conformal structure arises in this way. The Ricci-flatness condition along the scale bundle as a lightlike hypersurface into these Lorentzian manifolds is studied by means of the initial velocity of the $1$-parameter family of self-adjoint tensor fields. Finally, flat M\"{o}bius structures are characterized in terms of the extrinsic geometry of the corresponding spacelike surfaces

Calibración de sensores de humedad capacitivos usando redes neuronales

X Jornadas de Investigación de la Zona no Saturada del Suelo, Salamanca (España), 2011El estudio de la variabilidad espacial de la humedad del suelo a escala de parcela o cuenca agrícola requiere el uso de redes de sensores de humedad de bajo coste, que suelen mostrar una fiabilidad limitada y requieren de calibraciones específicas, especialmente en suelos con elevados contenidos en arcilla. El presente trabajo pretende plantear una calibración más fiable de sondas de humedad mediante un análisis mixto campo-laboratorio. Para la calibración de campo se dispone de datos gravimétricos; para la calibración en laboratorio se han usado columnas de suelo inalterado que tras ser saturadas fueron desecadas en un entorno controlado mientras se monitorizaba la evolución de su peso y la de su humedad volumétrica, medida con diferentes sondas capacitivas Decagon. Tras obtener curvas de secado y la relación entre la humedad gravimétrica y la volumétrica es posible realizar una calibración mejorada específica para cada tipo de suelo. Las redes neuronales son particularmente útiles para el modelado de procesos físicos y el ajuste de modelos. En este trabajo se propone el empleo de dichas herramientas para obtener calibraciones para las sondas analizadas en el tipo de suelo objeto de estudio. Los resultados muestran que dichas calibraciones permiten mejorar la precisión de las mediciones de humedad realizadas.The study of the spatial variability of soil water content at agricultural plot or catchment scales requires the use of low-cost soil water content sensor networks, which usually show a limited reliability and require specific calibrations, specially for soils with a high clay content. This work proposes a more reliable calibration of soil water content probes with a laboratory analysis. Minimally disturbed soil columns were saturated with water and dried in a controlled environment while monitorizing the evolution of their volumetric soil water content (with different capacitive Decagon Probes) and weights. After obtaining the drying curves and the relation between the volumetric and the measured gravimetric soil water contents it is possible to achieve an improved calibration specific for different kinds of soil. Neural networks are especially interesting for the modeling of physical processes and model adjustment. In this work, these tools were used in order to obtain improved calibrations for the analyzed probes in the studied soil type. Results show that this calibration improves the accuracy and pMinisterio de Ciencia e Innovación AGL2009 C03-03Junta de Andalucía AGR-478

Comparing Electronic Monitoring and human observer collected fishery data in the tropical purse seine operating in the Western and Central Pacific Ocean

Electronic Monitory (EM) systems have been proven a valid tool for collecting fishery dependent data. They are being widely used in many fisheries as a complement or alternative to human observers to increase the monitoring coverage of fisheries. However, considering its wide application, following agreed minimum standard, it is important to compare the congruence between the information collected by EM and observers. We compared EM and two sets of different observer data collected on 6 trips of tuna purse seiners in the Eastern and Western and Central Pacific Ocean to analyze the similarity of fishing set type identification, estimation of tuna and bycatch catches between both monitoring systems. Overall EM was a valid tool to estimate the type of fishing set. Retained total catch of tunas by set was estimated by EM as reliable as that by both observer programs and logbook. When comparing the information by set, EM estimation of the main species, such as skipjack and bigeye and the combination of bigeye/yellowfin, was proven to be less accurate but statistically similar to the estimates made by both observers’ programs. EM tended to underestimate the retained catch of skipjack in comparison to both observers estimates and slightly overestimate bigeye and yellowfin, the overestimation being less pronounced for bigeye than for yellowfin. For bycatch species, EM is able to identify main bycatch species as observers do. However, the capability of EM to estimate the same number of bycatch items in comparison to IATTC and WCPFC observers varies greatly by species group. For sharks, which are the main bycatch issue in the FAD purse seine fishery, the overall congruence between EM and observers was high. EM and IATTC observer identified a similar overall number of individual sharks, however, WCPFC observers estimated lower number of shark individuals than the other two monitoring systems when considering all trips together.Versión del edito

Interaction between Calpain 5, Peroxisome proliferator-activated receptor-gamma and Peroxisome proliferator-activated receptor-delta genes: a polygenic approach to obesity

<p>Abstract</p> <p>Context</p> <p>Obesity is a multifactorial disorder, that is, a disease determined by the combined effect of genes and environment. In this context, polygenic approaches are needed.</p> <p>Objective</p> <p>To investigate the possibility of the existence of a crosstalk between the <it>CALPAIN 10 </it>homologue <it>CALPAIN 5 </it>and nuclear receptors of the peroxisome proliferator-activated receptors family.</p> <p>Design</p> <p>Cross-sectional, genetic association study and gene-gene interaction analysis.</p> <p>Subjects</p> <p>The study sample comprise 1953 individuals, 725 obese (defined as body mass index ≥ 30) and 1228 non obese subjects.</p> <p>Results</p> <p>In the monogenic analysis, only the peroxisome proliferator-activated receptor delta (<it>PPARD</it>) gene was associated with obesity (OR = 1.43 [1.04–1.97], p = 0.027). In addition, we have found a significant interaction between <it>CAPN5 </it>and <it>PPARD </it>genes (p = 0.038) that reduces the risk for obesity in a 55%.</p> <p>Conclusion</p> <p>Our results suggest that <it>CAPN5 </it>and <it>PPARD </it>gene products may also interact in vivo.</p

Design of a specific physical training program for first-time participants in basic life support

Objetivo: diseñar un programa de entrenamiento físico específico para profesionales del soporte vital básico que permita superar la fatiga que éstos padecen durante el desarrollo de la reanimación cardiopulmonar con el fin de proporcionar un masaje cardiaco de mayor calidad durante periodos de tiempo más largos. Método: el entrenamiento interválico de alta intensidad mejora la capacidad física y la salud al tiempo que reduce los niveles de grasa y aumenta el metabolismo basal mediante la alternancia entre ejercicios de alta y baja intensidad mejorando la capacidad anaeróbica y la disponibilidad aeróbica, lo que hace de este tipo de entrenamiento una herramienta idónea para trabajar con los profesionales de la reanimación cardiopulmonar. Resultado: programa de entrenamiento por estaciones que combinando actividades dinámicas de alta intensidad, ejercicios de fuerza en los que se implica directamente la musculatura interviniente en la reanimación cardiopulmonar y ejercicios en los que se utiliza el propio simulador de reanimación cardiopulmonar, permite adecuarnos al entrenamiento de alta intensidad aumentando la fuerza y la funcionalidad. Conclusiones: la relación existente entre el ejercicio físico y la calidad de las técnicas de reanimación cardiopulmonar impone la necesidad de desarrollar estudios específicos de las rutas metabólicas y los grupos musculares específicos que participan en estas técnicas con el objetivo de generar un programa de entrenamiento físico específico para los profesionales que participan en esta actividad para mejorar la calidad de dichas técnicas e influir de forma positiva en la supervivencia de los pacientes afectados por un episodio de parada cardiorrespiratoria.Objective: to design a specific physical training program for basic life support professionals to overcome the fatigue they suffer during the development of cardiopulmonary resuscitation in order to provide a higher quality cardiac massage for longer periods. Method: high intensity interval training improves physical fitness and health, reduce fat levels and increase basal metabolism by high and low intensity exercises alternation, improving anaerobic capacity and aerobic availability, which make this type of training an ideal tool for working with cardiopulmonary resuscitation professionals. Result: a circuit training program that allow us for adapting to a high intensity interval training combining high intensity activities, strength exercises that work the participant musculature in cardiopulmonary resuscitation and exercises in which the cardiopulmonary resuscitation simulator is used. Conclusions: the connection between physical exercise and cardiopulmonary resuscitation techniques quality impose the need to develop specific studies of metabolic pathways and participant muscle groups in cardiopulmonary resuscitation to generate a specific physical training program for professionals who participate in this activity in order to improve these techniques quality and cardiorespiratory arrest survival

Pathogenicity and virulence of Listeria monocytogenes: A trip from environmental to medical microbiology

Listeria monocytogenes is a saprophytic gram-positive bacterium, and an opportunistic foodborne pathogen that can produce listeriosis in humans and animals. It has evolved an exceptional ability to adapt to stress conditions encountered in different environments, resulting in a ubiquitous distribution. Because some food preservation methods and disinfection protocols in foodprocessing environments cannot efficiently prevent contaminations, L. monocytogenes constitutes a threat to human health and a challenge to food safety. In the host, Listeria colonizes the gastrointestinal tract, crosses the intestinal barrier, and disseminates through the blood to target organs. In immunocompromised individuals, the elderly, and pregnant women, the pathogen can cross the blood-brain and placental barriers, leading to neurolisteriosis and materno-fetal listeriosis. Molecular and cell biology studies of infection have proven L. monocytogenes to be a versatile pathogen that deploys unique strategies to invade different cell types, survive and move inside the eukaryotic host cell, and spread from cell to cell. Here, we present the multifaceted Listeria life cycle from a comprehensive perspective. We discuss genetic features of pathogenic Listeria species, analyze factors involved in food contamination, and review bacterial strategies to tolerate stresses encountered both during food processing and along the host’s gastrointestinal tract. Then we dissect host–pathogen interactions underlying listerial pathogenesis in mammals from a cell biology and systemic point of view. Finally, we summarize the epidemiology, pathophysiology, and clinical features of listeriosis in humans and animals. This work aims to gather information from different fields crucial for a comprehensive understanding of the pathogenesis of L. monocytogenes

Adipose tissue knockdown of lysozyme reduces local inflammation and improves adipogenesis in high-fat diet-fed mice

Chronic systemic low-level inflammation in metabolic disease is known to affect adipose tissue biology. Lysozyme (LYZ) is a major innate immune protein but its role in adipose tissue has not been investigated. Here, we aimed to investigate LYZ in human and rodents fat depots, and its possible role in obesity-associated adipose tissue dysfunction. LYZ mRNA and protein were identified to be highly expressed in adipose tissue from subjects with obesity and linked to systemic chronic-low grade inflammation, adipose tissue inflammation and metabolic disturbances, including hyperglycemia, dyslipidemia and decreased markers of adipose tissue adipogenesis. These findings were confirmed in experimental models after a high-fat diet in mice and rats and also in ob/ob mice. Importantly, specific inguinal and perigonadal white adipose tissue lysozyme (Lyz2) gene knockdown in high-fat diet-fed mice resulted in improved adipose tissue inflammation in parallel to reduced lysozyme activity. Of note, Lyz2 gene knockdown restored adipogenesis and reduced weight gain in this model. In conclusion, altogether these observations point to lysozyme as a new actor in obesity-associated adipose tissue dysfunction. The therapeutic targeting of lysozyme production might contribute to improve adipose tissue metabolic homeostasis

Genetic Structure of the Spanish Population

<p>Abstract</p> <p>Background</p> <p>Genetic admixture is a common caveat for genetic association analysis. Therefore, it is important to characterize the genetic structure of the population under study to control for this kind of potential bias.</p> <p>Results</p> <p>In this study we have sampled over 800 unrelated individuals from the population of Spain, and have genotyped them with a genome-wide coverage. We have carried out linkage disequilibrium, haplotype, population structure and copy-number variation (CNV) analyses, and have compared these estimates of the Spanish population with existing data from similar efforts.</p> <p>Conclusions</p> <p>In general, the Spanish population is similar to the Western and Northern Europeans, but has a more diverse haplotypic structure. Moreover, the Spanish population is also largely homogeneous within itself, although patterns of micro-structure may be able to predict locations of origin from distant regions. Finally, we also present the first characterization of a CNV map of the Spanish population. These results and original data are made available to the scientific community.</p

Calpain-5 gene variants are associated with diastolic blood pressure and cholesterol levels

BACKGROUND: Genes implicated in common complex disorders such as obesity, type 2 diabetes mellitus (T2DM) or cardiovascular diseases are not disease specific, since clinically related disorders also share genetic components. Cysteine protease Calpain 10 (CAPN10) has been associated with T2DM, hypertension, hypercholesterolemia, increased body mass index (BMI) and polycystic ovary syndrome (PCOS), a reproductive disorder of women in which isunlin resistance seems to play a pathogenic role. The calpain 5 gene (CAPN5) encodes a protein homologue of CAPN10. CAPN5 has been previously associated with PCOS by our group. In this new study, we have analysed the association of four CAPN5 gene variants(rs948976A>G, rs4945140G>A, rs2233546C>T and rs2233549G>A) with several cardiovascular risk factors related to metabolic syndrome in general population. METHODS: Anthropometric measurements, blood pressure, insulin, glucose and lipid profiles were determined in 606 individuals randomly chosen from a cross-sectional population-based epidemiological survey in the province of Segovia in Central Spain (Castille), recruited to investigate the prevalence of anthropometric and physiological parameters related to obesity and other components of the metabolic syndrome. Genotypes at the four polymorphic loci in CAPN5 gene were detected by polymerase chain reaction (PCR). RESULTS: Genotype association analysis was significant for BMI (p ≤ 0.041), diastolic blood pressure (p = 0.015) and HDL-cholesterol levels (p = 0.025). Different CAPN5 haplotypes were also associated with diastolic blood pressure (DBP) (0.0005 ≤ p ≤ 0.006) and total cholesterol levels (0.001 ≤ p ≤ 0.029). In addition, the AACA haplotype, over-represented in obese individuals, is also more frequent in individuals with metabolic syndrome defined by ATPIII criteria (p = 0.029). CONCLUSION: As its homologue CAPN10, CAPN5 seems to influence traits related to increased risk for cardiovascular diseases. Our results also may suggest CAPN5 as a candidate gene for metabolic syndrome