Time-variant failure probability of critical slopes under strong rainfall hazard including mitigation effects

Se presenta una formulación probabilista para evaluar el nivel de seguridad de taludes sujetos a lluvias intensas.The time-variant failure probability for critical slopes under strong rainfalls, which cause reductions on the soil shear strength, is calculated and compared to the target failure probability. The soil properties and the rainfall characteristics are considered as random and the correlation between rainfall intensity and duration is included to assess the impact of water infiltration on the slope failure probability. The failure probability, defined as the probability that the safety factor is less than 1, is calculated through a Monte Carlo simulation process. The paper emphasizes the importance of the time during the water infiltration into the soil, as the rainfall sequence occurs. The target failure probability, derived from the minimum expected life-cycle cost, is compared to the slope failure probability to decide if the slope requires mitigation measures. If mitigation is required, the slope model is modified and a new annual failure probability is calculated. The slope annual failure probability, for 3 sites under strong rainfall hazard, is found to be around 0.78. However, by introducing mitigation actions, the failure probability reduces to 0.037. The slope failure probability allows for the risk-based prioritization of slopesConacyt, Problemas Nacionales, proyecto 24778

SEXUAL SIZE DIMORPHISM, DIET, AND REPRODUCTION IN THE MEXICAN GARTER SNAKE, THAMNOPHIS EQUES

Although adult T. eques females had a longer SVL and HL than males, the sexes did not differ in their diet, and we found that larger females had more offspring. These results suggest that sexual size dimorphism in natural populations of T. eques may be determined by fecundity selection rather than by the ecological factors associated with the spectrum of available prey sizes. The lack of intersexual differences in the slope of the regression between HL and SVL, and the upward shift in the intercept of the regression line for females together with the shift along the common slope toward larger females (data for larger females do not overlap with the data for larger males), showed that the larger heads of the females are probably an outcome of their larger bodies (SVL) and not of the allometric relationship between these traits.In this study we examined diet, reproduction, and sexual dimorphism in body size of adult Thamnophis eques. We measured 307 adult snakes within the hydrologic system of High Lerma. Prey was obtained by forced regurgitation when snakes were collected, and gravid females were housed in the laboratory until parturition. Females had a longer snout-vent length and shorter tails than males, but there was no difference in total length between the two sexes. We found no evidence to support the hypothesis that sexual dimorphism is due to differences in prey size for this species because the sexes did not differ in the type and mass of prey they consumed; however, the size of gravid females was positively related to the number, but not size and weight, of their offspring. Our results suggested that sexual size dimorphism in natural populations of T. eques may be determined by fecundity selection rather than the ecological factors associated with the spectrum of available prey sizes. We also discuss possible reasons why the sexes did not differ in total lengthUniversidad Autónoma del Estado de México 2077/2005U, 2365/2006, 2865/2010U Consejo Nacional de Ciencia y Tecnología (33710)

Effect of Juvenile Hormone on Resistance against Entomopathogenic Fungus Metarhizium robertsii Differs between Sexes

Juvenile hormone has been suggested to be a potential mediator in the trade-off between mating and insects' immunity. Studies on various insect taxons have found that juvenile hormone interferes with humoral and cellular immunity. Although this was shown experimentally, studies using highly virulent parasites or pathogens are lacking so far. In this study, we tested if juvenile hormone administration affected resistance against entomopathogenic fungi, Metarhizium robertsii, in the mealworm beetle, Tenebrio molitor. In previous studies with T. molitor, juvenile hormone has been found to reduce a major humoral immune effector-system (phenoloxidase) in both sexes and decrease the encapsulation response in males. Here, we found that juvenile hormone administration prolonged survival time after infection with M. robertsii in males but reduced survival time in females. This study indicates that the effects of juvenile hormone on insect immunity might be more complicated than previously considered. We also suggest that there might be a trade-off between specific and non-specific immunity since, in males, juvenile hormone enhances specific immunity but corrupts non-specific immunity. Our study highlights the importance of using real parasites and pathogens in immuno-ecological studies

Self-Perceived Facial Attractiveness, Fluctuating Asymmetry, and Minor Ailments Predict Mental Health Outcomes

Objective Phenotypic markers associated with developmental stability such as fluctuating asymmetry, facial attractiveness, and reports of minor ailments can also act as indicators of overall physical health. However, few studies have assessed whether these markers might also be cues of mental health. We tested whether self- and other-perceived facial attractiveness, fluctuating asymmetry, and minor ailments are associated with psychopathological symptoms in a mixed sample of 358 college students, controlling for the effects of body mass index, age, and sex.Methods We applied the Symptom Checklist-90-Revised (SCL-90-R) questionnaire to assess psychopathological symptoms, a battery of questionnaires about self-perceptions of facial attractiveness, and gathered information about the number of previous minor ailments as well as demographic data. Other-perceived attractiveness was assessed by an independent mixed sample of 109 subjects. Subjects' facial fluctuating asymmetry was determined by geometric morphometrics.Results The results revealed that in both men and women, higher self-perceived attractiveness and fewer minor ailments predicted lower scores of Somatization, Obsessive-Compulsive, Interpersonal Sensitivity, Depression, Anxiety, Phobic Anxiety, Paranoid Ideation, Psychoticism, and a General Psychopathology Index. Higher facial fluctuating asymmetry was associated with higher Interpersonal Sensitivity, but did not contribute to its prediction when controlling for the other studied variables.Conclusions The observed strong associations between self-perceived attractiveness, minor ailments, and psychopathology indicate common developmental pathways between physiological and psychological symptomatology which may reflect broader life history (co)variation between genetics, developmental environment, and psychophysiological functioning.</p

Caracterización de bacterias halófilas aisladas de un cultivo a cielo abierto tipo raceway de espirulina

Los microorganismos halófilos tienen su origen en los tres dominios de la vida: Archea, Bacteria y Eucarya. Con el objetivo de caracterizar morfológica y molecularmente 6 cepas bacterias halófilas aisladas de un cultivo a cielo abierto en sistema “raceway” de espirulina, se realizó una prueba fisiológica para definir el rango de salinidad en el que las cepas bacterianas presentan crecimiento, éstas se inocularon en agar nutritivo a diferentes porcentajes de NaCl, en intervalos de 5, desde 5 hasta 20%. Además, se les aplicó la tinción de Gram y las pruebas bioquímicas de catalasa y oxidasa. El análisis molecular constó del aislamiento de DNA genómico y mediante la PCR se amplificó y secuenció la región del 16S DNAr. Las secuencias obtenidas se analizaron con el algoritmo del BLAST del NCBI. La comparación de las secuencias de las cepas estudiadas, así como los datos morfológicos y bioquímicos mostraron que pertenecen a los géneros: Bacillus, Halomonas y Pseudomonas.The halophilic microorganisms have their origin in the three domains of life: Archea, Bacteria and Eucarya. Due to the fact of characterize morphologically and molecularly six strains of halophilic bacteria isolated from an open sky growing in a race-way system of spirulina. A physiological test was made to define the range of salinity where the bacterial strains demonstrate growth; these were inoculated in nutritive agar in different percentages of NaCl in intervals of 5, from 5 to 20%. Also, a Gram’s dying process was applied as well as catalase and oxidase biochemical tests were made. The molecular analysis was about isolating genomic DNA, the 16s DNAr was amplified by PCR. The sequences gotten were analyzed with the BLAST in the database NCBI. The comparison between the sequence of strains studied as well as the morphological and biochemical data showed that these belong to the gender of Bacillus, Halomonas and Pseudomonas

Physiological stress and higher reproductive success in bumblebees are both associated with intensive agriculture

Free-living organisms face multiple stressors in their habitats, and habitat quality often affects development and life history traits. Increasing pressures of agricultural intensification have been shown to influence diversity and abundance of insect pollinators, and it may affect their elemental composition as well. We compared reproductive success, body concentration of carbon (C) and nitrogen (N), and C/N ratio, each considered as indicators of stress, in the buff-tailed bumblebee (Bombus terrestris). Bumblebee hives were placed in oilseed rape fields and semi-natural old apple orchards. Flowering season in oilseed rape fields was longer than that in apple orchards. Reproductive output was significantly higher in oilseed rape fields than in apple orchards, while the C/N ratio of queens and workers, an indicator of physiological stress, was lower in apple orchards, where bumblebees had significantly higher body N concentration. We concluded that a more productive habitat, oilseed rape fields, offers bumblebees more opportunities to increase their fitness than a more natural habitat, old apple orchards, which was achieved at the expense of physiological stress, evidenced as a significantly higher C/N ratio observed in bumblebees inhabiting oilseed rape fields

Developmental speed affects ecological stoichiometry and adult fat reserves in Drosophila melanogaster

The elemental composition of organisms belongs to a suite of functional traits that change during development in response to environmental conditions. However, associations between adaptive variations in developmental speed and elemental body composition are not well understood. We compared body mass, elemental body composition, food uptake and fat metabolism of Drosophila melanogaster male fruit flies in relation to their larval development speed. Slowly developing flies had higher body carbon concentration than rapidly developing and intermediate flies. Rapidly developing flies had the highest body nitrogen concentration, while slowly developing flies had higher body nitrogen levels than flies with intermediate speed of development. The carbon-to-nitrogen ratio was therefore lower in rapidly developing flies than in slow and intermediate flies. We also had a group of flies grown individually and their body mass and elemental body composition were similar to those of rapidly developing individuals grown in groups. This suggests that rapid growth is not suppressed by stress. Feeding rates were lowest in the slowly developing flies. The amount of triacylglycerides was highest in the flies with intermediate developmental speed which optimizes development under many climatic conditions. Although low food intake slows down developmental speed and the accumulation of body fat reserves in slowly developing flies, their phenotype conceivably facilitates survival under higher stochasticity of their environments. Rapidly developing flies grew with less emphasis on storage build-up. Overall, this study shoes that a combination of bet-hedging, adaptive tracking and developmental plasticity enables fruit flies to respond adaptively to environmental uncertainty.</p

Socioeconomic position, immune function, and its physiological markers

The development of costly traits such as immune function and secondary sexual traits is constrained by resource availability. The quality of developmental conditions and the availability of resources in ontogeny may therefore influence immune system functions and other biological traits. We analyzed causal pathways between family socioeconomic position, strength of immune response, and five physiological biomarkers in young Latvian men (n = 93) using structural equation modeling. Men from wealthier families had higher testosterone levels (rs = 0.280), stronger immune response (rs = 0.551), and higher facial attractiveness (rs = 0.300). There were weak, non-significant correlations between family income, body fat percentage (rs = −0.147), and fluctuating asymmetry (rs = −0.159). Testosterone partially (33.8%) mediated the effect of family income on facial masculinity. Testosterone (positively) and adiposity (negatively) partially (4%) mediated the relationship between family income and immune function. Higher facial masculinity, higher facial symmetry, and lower adiposity were reliable and independent cues of better immune function (R2 = 0.238) in a larger sample of young Latvian men (N = 146). Resource availability in ontogeny has an important role for the development of immune function and physical appearance, and it is a key parameter to be included in human eco-immunological research

Women's preferences for men's facial masculinity are strongest under favorable ecological conditions

The strength of sexual selection on secondary sexual traits varies depending on prevailing economic and ecological conditions. In humans, cross-cultural evidence suggests women's preferences for men's testosterone dependent masculine facial traits are stronger under conditions where health is compromised, male mortality rates are higher and economic development is higher. Here we use a sample of 4483 exclusively heterosexual women from 34 countries and employ mixed effects modelling to test how social, ecological and economic variables predict women's facial masculinity preferences. We report women's preferences for more masculine looking men are stronger in countries with higher sociosexuality and where national health indices and human development indices are higher, while no associations were found between preferences and indices of intra-sexual competition. Our results show that women's preferences for masculine faces are stronger under conditions where offspring survival is higher and economic conditions are more favorable