Do the blood anti-Müllerian hormone concentrations in young females correlate with the ovarian follicular population later in life in water buffalo?

In this longitudinal study, the anti-Müllerian hormone (AMH) levels in blood were determined in 32 Murrah buffalo females at 8, 10, 12, 16 and 19 months of age when females were synchronized and the antral follicular population (AFP) was estimated. Correlations of AFP to the AMH level at 19 months of age and retrospectively to younger ages were investigated. Then females were split into high and low AFP, and their AMH levels were compared for all ages and tested as predictors of AFP categories. The highest AMH level (p < .05) was detected at 8 months, reducing but not differing (p > .05) at 10, 12 and 16 months then reducing again (p < .05) at 19 months of age. The mean AFP was 17.6 ± 6.3 follicles, and it was positively correlated with AMH in all ages tested. High AFP females had approximately two times more antral follicles than low AFP (p < .05) and their AMH levels were higher (p < .01) than in low AFP ones in all ages. Only at 8 months, AMH levels can be used to precociously detect high AFP heifers (a cut-off point of 464.7 pg/mL; p < .05), while low AFP heifers could be detected by AMH measurements at 8, 10, 12 and 16 months of age (p < .05). We conclude that AMH of buffalo calves correlates with AFP of heifers later in life and depending on the age, its levels could be used to identify future females with low or high AFP.

Use, perception, and local management of Copernicia prunifera (Miller) H. E. Moore in rural communities in the Brazilian Savanna.

BACKGROUND: Copernicia prunifera belongs to the Arecaceae family, and its production chain includes a set of economic activities based on the use of the stipe, petiole, fiber, fruits, roots, and leaves from which carnaúba wax is extracted, an economically valuable resource in the region. This study aimed to evaluate the uses, management, and perception of the species by local extractors. METHODS: Two communities were studied, Bem Quer, where 15 extractors of carnaúba leaves were interviewed, and Cana, where 21 extractors considered specialists were interviewed, totaling a sample of 36 interviewees. Interviewees were asked questions about uses, ways of handling, and perception of morphological variation in the carnaúba leaves. The number of leaves extracted and the income obtained from the sale of leaves were estimated from interviews and notes that each leader of extractors held during the year of the research and previous years, as well as direct observations made by researchers in the communities which recollection area of straw hold about 80 thousand individuals of C. prunifera. A regression analysis was used to explore the relationships between social variables (age, time in extractive activity, and income obtained from extraction) with the number of leaves exploited. RESULTS: The leaf was indicated as the most used part, from which an important powder is extracted for the production of wax. In addition, the leaf was also indicated to be used for fertilization and construction. The relationship between the socioeconomic variables, income from extraction, and the number of leaves extracted (in thousands) was significant (R2 = 0.73 and p < 0.001). However, the other variables analyzed in this study, such as the time spent extracting leaves and the years of residence in the community (R2 = 0.03 and p > 0.05); the number of leaves extracted and interviewee age (R2= 0.05 and p > 0.05); and the number of leaves extracted and extraction time (R2 = 0.04 and p > 0.05) did not indicate a relationship. CONCLUSION: Local extractors observed that new leaves have the highest sales value, as they have the highest production of powder. In addition, economic factor is the preponderant force that directs the management strategies of native species. For this species, however, morphological and genetic studies are needed for further clarification.

Force Field for Water over Pt(111): Development, Assessment, and Comparison.

Metal/water interfaces are key in many natural and industrial processes, such as corrosion, atmospheric, or environmental chemistry. Even today, the only practical approach to simulate large interfaces between a metal and water is to perform force-field simulations. In this work, we propose a novel force field, GAL17, to describe the interaction of water and a Pt(111) surface. GAL17 builds on three terms: (i) a standard Lennard-Jones potential for the bonding interaction between the surface and water, (ii) a Gaussian term to improve the surface corrugation, and (iii) two terms describing the angular dependence of the interaction energy. The 12 parameters of this force field are fitted against a set of 210 adsorption geometries of water on Pt(111). The performance of GAL17 is compared to several other approaches that have not been validated against extensive first-principles computations yet. Their respective accuracy is evaluated on an extended set of 802 adsorption geometries of H2O on Pt(111), 52 geometries derived from icelike layers, and an MD simulation of an interface between a c(4 × 6) Pt(111) surface and a water layer of 14 Å thickness. The newly developed GAL17 force field provides a significant improvement over previously existing force fields for Pt(111)/H2O interactions. Its well-balanced performance suggests that it is an ideal candidate to generate relevant geometries for the metal/water interface, paving the way to a representative sampling of the equilibrium distribution at the interface and to predict solvation free energies at the solid/liquid interface.

Fetal sex alters maternal anti-Mullerian hormone during pregnancy in cattle.

Anti-Mullerian hormone (AMH) is expressed by both male and female fetuses during mammalian development, with males expressing AMH earlier and at significantly higher concentration. The aim of the current study was to explore the potential impact of pregnancy and fetal sex on maternal AMH and to determine if plasma (Pl) AMH or placenta intercotyledonary membrane and cotyledonary AMH receptor 2 (AMHR2) mRNA expression differ in pregnant cows carrying male vs. female fetuses. AMH levels in blood were measured using a bovine optimized ELISA kit. Cows pregnant with a male fetus were observed to have a significantly greater difference in Pl AMH between day 35 and 135 of gestation. Average fetal AMH level between 54 and 220days of gestation was also observed to be significantly higher in male vs. female fetuses. Intercotyledonary membranes and cotyledons were found to express AMHR2 between days 38 and 80 of gestation at similar levels in both fetal sexes. These findings support the hypothesis that fetal sex alters maternal Pl AMH during pregnancy in cattle.

Molecular mechanics models for the image charge, a comment on "including image charge effects in the molecular dynamics simulations of molecules on metal surfaces".

We re-investigate the image charge model of Iori and Corni (Iori and Corni, J. Comput. Chem. 2008, 29, 1656). We find that a simple symmetrization of their model allows to obtain quantitatively correct results for the electrostatic interaction of a water molecule with a metallic surface. This symmetrization reduces the magnitude of the electrostatic interaction to less than 10% of the total interaction energy. © 2017 Wiley Periodicals, Inc.

Capturing Solvation Effects at a Liquid/Nanoparticle Interface by Ab Initio Molecular Dynamics: Pt201 Immersed in Water.

Solvation can substantially modify the adsorption properties of heterogeneous catalysts. Although essential for achieving realistic theoretical models, assessing such solvent effects over nanoparticles is challenging from a computational standpoint due to the complexity of those liquid/metal interfaces. This effect is investigated by ab initio molecular dynamics simulations at 350 K of a large platinum nanoparticle immersed in liquid water. The first solvation layer contains twice as much physisorbed water molecules above the terraces, than chemisorbed ones located only at edges and corners. The solvent stabilizes the binding energy of chemisorbates: 66% of the total gain comes from interactions with physisorbed molecules and 34% from the influence of bulk liquid.

Coverage-dependent thermodynamic analysis of the formation of water and hydrogen peroxide on a platinum model catalyst.

Understanding the selectivity of the oxygen reduction reaction, especially the formation of water versus hydrogen peroxide in fuel cells, is an ongoing challenge in electrochemistry, surface science and catalysis. In this study, we propose a comprehensive thermodynamic analysis of the reaction intermediates for the formation of water on Pt(111). Density functional theory calculations of all the elementary steps linking hydroxyl and hydroperoxyl surface species with water and hydrogen peroxide have been performed at low (1/12 ML, ML = monolayer) and high (1/4 ML) coverages. The reaction energy variation for the two competing elementary events (molecular oxygen dissociation and hydroperoxyl formation) is strongly coverage-dependent. For the direct dissociation, an increase is observed at low coverage with respect to the usual high coverage picture. The stability of the reaction intermediates is investigated from thermodynamic diagrams. At 353 K and a total pressure of 1 atm, water and hydroxyl surface species are expected to compete for adsorption on Pt(111).

HIV prevalence among blood donors in a blood bank in Curitiba (Brazil).

There still is no cure for the acquired immunodeficiency syndrome (AIDS). Its etiologic agent is the human immunodeficiency virus (HIV), and transmission occurs through sexual relationships, contacts with blood, and vertically (mother to child). In this study, we sought to determine the prevalence of HIV among blood donors at a blood bank in Curitiba. We studied 213,666 blood donations made from March 1, 1992, to April 25, 1999. Each potential blood donor first answered a questionnaire, submitted to a clinical examination, and filled out a self-exclusion card. Blood was collected and analyzed only from the candidates approved by the first two criteria. Two tests were used to detect HIV: ELISA for screening, and Western-Blot for confirmation. The results were analyzed statistically by determining the 95% confidence interval. Of the total number of donors, 156,942 were men, and 56,724 were women. There were 319 cases of HIV infection (244 men, 75 women). There were no significant differences between genders, or among the different age groups, or between first-donation and repeated-donation donors. There was a significant predominance of HIV infection among single individuals compared to married, widowed, and other individuals. The same occurred among married and divorced individuals compared to widowed subjects. The prevalence of HIV among blood donors was 0.149% (0.155% among men and 0.132% among women). The frequency of HIV was statistically identical among new blood donors and repeat donors. A large number of HIV-infected married women was also observed.