Flujo en medio poroso no saturado con conductividad hidráulica discontinua (planteamiento del problema)

When studying the flow in an unsaturated porous medium from a point recharge, two phenomena are identified: In the first the residual soil retention conditions are negligible, the mass of water available to flow is constant in time, for So the dimensional analysis considering first order self similarity is sufficient to solve the known diffusion equation. Conversely, if residual soil retention is taken into account, the mass of water available to flow is variable over time because the capillary forces retain some of the water in the pores, so that the mass does not comply with a law Of conservation and the assumption of previous self similarity is not valid. Then another type of self-similar assumption is called the second order, in which the so-called anomalous exponents appear. Under these conditions the equation to be solved is nonlinear with discontinuous coefficient and is called the Baremblatt Equation. The dimensional analysis is not enough to obtain the complete solution one goes to other different techniques, in this case to solve a problem of self value. In the second part will present the numerical solution and the application of this problemCuando se estudia elflujo en un medio poroso no saturado a partir de una recarga puntual, seidentifican dos fenómenos: En el primero las condiciones de retención residual del suelo sondespreciables, la masa de agua disponible para fluir es constante en el tiempo, por lo tanto elanálisis dimensional considerando autosimilaridad de primer orden es suficientepara solucionarla conocida Ecuación de difusión. Por el contrario, si se tiene en cuenta la retención residualdel suelo, la masa de agua disponible para fluir es variable con el tiempo debido a que lasfuerzas de capilaridad retienen parte del agua en los poros, por lo tanto la masa no cumple unaley de conservación y la suposición de autosimilaridad anterior no es válida. Se consideraentonces otro tipo de suposición autosimilar llamada de segundo orden, en la cual aparecen losllamados exponentes anómalos. Bajo estas condiciones la ecuación a solucionar es no linealcon coeficiente discontinuo y recibe el nombre deEcuación de Baremblatt. El análisis dimensionalno es suficientepara obtener la solución completa y se acude a otras técnicas diferentes, en estecaso a resolver un problema de autovalor. En la segunda parte sepresentara la solución numericay la aplicación de este problema

Flujo en medio poroso no saturado con conductividad hidráulica discontinua (planteamiento del problema)

When studying the flow in an unsaturated porous medium from a point recharge, two phenomena are identified: In the first the residual soil retention conditions are negligible, the mass of water available to flow is constant in time, for So the dimensional analysis considering first order self similarity is sufficient to solve the known diffusion equation. Conversely, if residual soil retention is taken into account, the mass of water available to flow is variable over time because the capillary forces retain some of the water in the pores, so that the mass does not comply with a law Of conservation and the assumption of previous self similarity is not valid. Then another type of self-similar assumption is called the second order, in which the so-called anomalous exponents appear. Under these conditions the equation to be solved is nonlinear with discontinuous coefficient and is called the Baremblatt Equation. The dimensional analysis is not enough to obtain the complete solution one goes to other different techniques, in this case to solve a problem of self value. In the second part will present the numerical solution and the application of this problemCuando se estudia elflujo en un medio poroso no saturado a partir de una recarga puntual, seidentifican dos fenómenos: En el primero las condiciones de retención residual del suelo sondespreciables, la masa de agua disponible para fluir es constante en el tiempo, por lo tanto elanálisis dimensional considerando autosimilaridad de primer orden es suficientepara solucionarla conocida Ecuación de difusión. Por el contrario, si se tiene en cuenta la retención residualdel suelo, la masa de agua disponible para fluir es variable con el tiempo debido a que lasfuerzas de capilaridad retienen parte del agua en los poros, por lo tanto la masa no cumple unaley de conservación y la suposición de autosimilaridad anterior no es válida. Se consideraentonces otro tipo de suposición autosimilar llamada de segundo orden, en la cual aparecen losllamados exponentes anómalos. Bajo estas condiciones la ecuación a solucionar es no linealcon coeficiente discontinuo y recibe el nombre deEcuación de Baremblatt. El análisis dimensionalno es suficientepara obtener la solución completa y se acude a otras técnicas diferentes, en estecaso a resolver un problema de autovalor. En la segunda parte sepresentara la solución numericay la aplicación de este problema

ILC3s restrict the dissemination of intestinal bacteria to safeguard liver regeneration after surgery.

It is generally believed that environmental or cutaneous bacteria are the main origin of surgical infections. Therefore, measures to prevent postoperative infections focus on optimizing hygiene and improving asepsis and antisepsis. In a large cohort of patients with infections following major surgery, we identified that the causative bacteria are mainly of intestinal origin. Postoperative infections of intestinal origin were also found in mice undergoing partial hepatectomy. CCR6+ group 3 innate lymphoid cells (ILC3s) limited systemic bacterial spread. Such bulwark function against host invasion required the production of interleukin-22 (IL-22), which controlled the expression of antimicrobial peptides in hepatocytes, thereby limiting bacterial spread. Using genetic loss-of-function experiments and punctual depletion of ILCs, we demonstrate that the failure to restrict intestinal commensals by ILC3s results in impaired liver regeneration. Our data emphasize the importance of endogenous intestinal bacteria as a source for postoperative infection and indicate ILC3s as potential new targets

Highlights from the Pierre Auger Observatory

The Pierre Auger Observatory is the world's largest cosmic ray observatory. Our current exposure reaches nearly 40,000 km$^2$ str and provides us with an unprecedented quality data set. The performance and stability of the detectors and their enhancements are described. Data analyses have led to a number of major breakthroughs. Among these we discuss the energy spectrum and the searches for large-scale anisotropies. We present analyses of our X$_{max}$ data and show how it can be interpreted in terms of mass composition. We also describe some new analyses that extract mass sensitive parameters from the 100% duty cycle SD data. A coherent interpretation of all these recent results opens new directions. The consequences regarding the cosmic ray composition and the properties of UHECR sources are briefly discussed.Comment: 9 pages, 12 figures, talk given at the 33rd International Cosmic Ray Conference, Rio de Janeiro 201

The Influence of Number and Timing of Pregnancies on Breast Cancer Risk for Women With BRCA1 or BRCA2 Mutations

International audienceBACKGROUND:Full-term pregnancy (FTP) is associated with a reduced breast cancer (BC) risk over time, but women are at increased BC risk in the immediate years following an FTP. No large prospective studies, however, have examined whether the number and timing of pregnancies are associated with BC risk for BRCA1 and BRCA2 mutation carriers.METHODS:Using weighted and time-varying Cox proportional hazards models, we investigated whether reproductive events are associated with BC risk for mutation carriers using a retrospective cohort (5707 BRCA1 and 3525 BRCA2 mutation carriers) and a prospective cohort (2276 BRCA1 and 1610 BRCA2 mutation carriers), separately for each cohort and the combined prospective and retrospective cohort.RESULTS:For BRCA1 mutation carriers, there was no overall association with parity compared with nulliparity (combined hazard ratio [HRc] = 0.99, 95% confidence interval [CI] = 0.83 to 1.18). Relative to being uniparous, an increased number of FTPs was associated with decreased BC risk (HRc = 0.79, 95% CI = 0.69 to 0.91; HRc = 0.70, 95% CI = 0.59 to 0.82; HRc = 0.50, 95% CI = 0.40 to 0.63, for 2, 3, and ≥4 FTPs, respectively, P trend < .0001) and increasing duration of breastfeeding was associated with decreased BC risk (combined cohort P trend = .0003). Relative to being nulliparous, uniparous BRCA1 mutation carriers were at increased BC risk in the prospective analysis (prospective hazard ration [HRp] = 1.69, 95% CI = 1.09 to 2.62). For BRCA2 mutation carriers, being parous was associated with a 30% increase in BC risk (HRc = 1.33, 95% CI = 1.05 to 1.69), and there was no apparent decrease in risk associated with multiparity except for having at least 4 FTPs vs. 1 FTP (HRc = 0.72, 95% CI = 0.54 to 0.98).CONCLUSIONS:These findings suggest differential associations with parity between BRCA1 and BRCA2 mutation carriers with higher risk for uniparous BRCA1 carriers and parous BRCA2 carriers

A global experiment on motivating social distancing during the COVID-19 pandemic

Finding communication strategies that effectively motivate social distancing continues to be a global public health priority during the COVID-19 pandemic. This cross-country, preregistered experiment (n = 25,718 from 89 countries) tested hypotheses concerning generalizable positive and negative outcomes of social distancing messages that promoted personal agency and reflective choices (i.e., an autonomy-supportive message) or were restrictive and shaming (i.e., a controlling message) compared with no message at all. Results partially supported experimental hypotheses in that the controlling message increased controlled motivation (a poorly internalized form of motivation relying on shame, guilt, and fear of social consequences) relative to no message. On the other hand, the autonomy-supportive message lowered feelings of defiance compared with the controlling message, but the controlling message did not differ from receiving no message at all. Unexpectedly, messages did not influence autonomous motivation (a highly internalized form of motivation relying on one’s core values) or behavioral intentions. Results supported hypothesized associations between people’s existing autonomous and controlled motivations and self-reported behavioral intentions to engage in social distancing. Controlled motivation was associated with more defiance and less long-term behavioral intention to engage in social distancing, whereas autonomous motivation was associated with less defiance and more short- and long-term intentions to social distance. Overall, this work highlights the potential harm of using shaming and pressuring language in public health communication, with implications for the current and future global health challenges

A global experiment on motivating social distancing during the COVID-19 pandemic

Finding communication strategies that effectively motivate social distancing continues to be a global public health priority during the COVID-19 pandemic. This cross-country, preregistered experiment (n = 25,718 from 89 countries) tested hypotheses concerning generalizable positive and negative outcomes of social distancing messages that promoted personal agency and reflective choices (i.e., an autonomy-supportive message) or were restrictive and shaming (i.e. a controlling message) compared to no message at all. Results partially supported experimental hypotheses in that the controlling message increased controlled motivation (a poorly-internalized form of motivation relying on shame, guilt, and fear of social consequences) relative to no message. On the other hand, the autonomy-supportive message lowered feelings of defiance compared to the controlling message, but the controlling message did not differ from receiving no message at all. Unexpectedly, messages did not influence autonomous motivation (a highly-internalized form of motivation relying on one’s core values) or behavioral intentions. Results supported hypothesized associations between people’s existing autonomous and controlled motivations and self-reported behavioral intentions to engage in social distancing: Controlled motivation was associated with more defiance and less long-term behavioral intentions to engage in social distancing, whereas autonomous motivation was associated with less defiance and more short- and long-term intentions to social distance. Overall, this work highlights the potential harm of using shaming and pressuring language in public health communication, with implications for the current and future global health challenges

Effects of Food Additives on Immune Cells As Contributors to Body Weight Gain and Immune-Mediated Metabolic Dysregulation

Food additives are compounds used in order to improve food palatability, texture, and shelf life. Despite a significant effort to assure safety of use, toxicological analysis of these substances, generally, rely on their direct toxicity to target organs (liver and kidney) or their genotoxic effects. Much less attention is paid to the effects of these compounds on cells of the immune system. This is of relevance given that metabolic dysregulation and obesity have a strong immune-mediated component. Obese individuals present a state of chronic low-grade inflammation that contributes to the establishment of insulin resistance and other metabolic abnormalities known as the metabolic syndrome. Obesity and metabolic syndrome are currently recognized as worldwide epidemics that pose a profound socioeconomic impact and represent a concern to public health. Cells of the immune system contribute to both the maintenance of “lean homeostasis” and the metabolic dysregulation observed in obese individuals. Although much attention has been drawn in the past decades to obesity and metabolic syndrome as a result of ingesting highly processed food containing large amounts of fat and simple sugars, mounting evidence suggest that food additives may also be important contributors to metabolic derangement. Herein, we review pieces of evidence from the literature showing that food additives have relevant effects on cells of the immune system that could contribute to immune-mediated metabolic dysregulation. Considering their potential to predispose individuals to develop obesity and metabolic syndrome, their use should be taken with caution or maybe revisited