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In this study, a systematic investigation of MoS2 nanostructure growth on a SiO2 substrate was conducted using a two-stage process. Initially, a thin layer of Mo was grown through sputtering, followed by a sulfurization process employing the CVD technique. This two-stage process enables the control of diverse nanostructure formations of both MoS2 and MoO3 on SiO2 substrates, as well as the formation of bulk-like grain structures. Subsequently, the addition of reduced graphene oxide (rGO) was examined, resulting in MoS2/rGO(n), where graphene is uniformly deposited on the surface, exposing a higher number of active sites at the edges and consequently enhancing electroactivity in the HER. The influence of the synthesis time on the treated MoS2 and also MoS2/rGO(n) samples is evident in their excellent electrocatalytic performance with a low overpotential. [ABSTRACT FROM AUTHOR]

The use of ML in agronomy has been increasing exponentially since the start of the century, including data-driven predictions of crop yields from farm-level information on soil, climate and management. However, little is known about the effect of data partitioning schemes on the actual performance of the models, in special when they are built for yield forecast. In this study, we explore the effect of the choice of predictive algorithm, amount of data, and data partitioning strategies on predictive performance, using synthetic datasets from biophysical crop models. We simulated sunflower and wheat data using OilcropSun and Ceres-Wheat from DSSAT for the period 2001-2020 in 5 areas of Spain. Simulations were performed in farms differing in soil depth and management. The data set of farm simulated yields was analyzed with different algorithms (regularized linear models, random forest, artificial neural networks) as a function of seasonal weather, management, and soil. The analysis was performed with Keras for neural networks and R packages for all other algorithms. Data partitioning for training and testing was performed with ordered data (i.e., older data for training, newest data for testing) in order to compare the different algorithms in their ability to predict yields in the future by extrapolating from past data. The Random Forest algorithm had a better performance (Root Mean Square Error 35-38%) than artificial neural networks (37-141%) and regularized linear models (64-65%) and was easier to execute. However, even the best models showed a limited advantage over the predictions of a sensible baseline (average yield of the farm in the training set) which showed RMSE of 42%. Errors in seasonal weather forecasting were not taken into account, so real-world performance is expected to be even closer to the baseline. Application of AI algorithms for yield prediction should always include a comparison with the best guess to evaluate if the additional cost of data required for the model compensates for the increase in predictive power. Random partitioning of data for training and validation should be avoided in models for yield forecasting. Crop models validated for the region and cultivars of interest may be used before actual data collection to establish the potential advantage as illustrated in this study. [ABSTRACT FROM AUTHOR]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.dsr.2009.09.006 Byline: Francisco Benitez-Villalobos, Julia P. Diaz-Martinez Keywords: Asteroidea; Deep-sea biology; Styracaster elongatus; NE Atlantic Abstract: We analysed the reproductive biology of the asteroid species Styracaster elongatus based on time-series samples from a 5000-m-deep site on the Porcupine Abyssal Plain (N.E. Atlantic). The ratio of males to females, the gonadosomatic index (GI), and pyloric caecum index (PCI) were determined and the results were corroborated by histological examination of the gonads. Fecundity and oocyte-size distribution were determined by histological and image analyses. Styracaster elongatus is a gonochoric asteroid and the ratio of males to females was not significantly different throughout the year. Oogenesis was asynchronous. The previtellogenic oocytes grew to a size of [approximately equal to]230[mu]m before undergoing vitellogenesis. Maximum oocyte size was [approximately equal to]620[mu]m. The ovary volume was mainly occupied by small previtellogenic oocytes (100-150[mu]m) at any one time. Mean GI was 6.38[+ or -]3.30 for females and 9.04[+ or -]4.1 for males. Mean PCI was 7.44[+ or -]1.66 for females and 7.66[+ or -]1.46 for males. Mean fecundity was 16,373[+ or -]5988 oocites per female. There were no seasonal variations in GI and fecundity. There was evidence of a pyiloric caecum seasonal development for females and males. For S. elongatus there is no direct relationship among seasonal primary production at the surface and production of vitellogenic oocytes. Nevertheless, this species takes advantage of the pulse of phytodetritus to the seabed by increasing the storage of nutrients in the pyloric caecum in order to maintain a constant production of eggs and sperm. Author Affiliation: Universidad del Mar, Carretera a Zipolite Km 1.5, 70902 Puerto Angel, Oaxaca, Mexico Article History: Received 10 November 2008; Revised 15 September 2009; Accepted 25 September 2009

An organism's maximum gonad investment (MGI) typically indicates its reproductive season and is often measured by the peak of the gonadosomatic index. Since external sexual dimorphism is often not evident, intrinsic sex differences remain unstudied. We analysed the reproductive seasonality of each sex of the broadcast-spawning sea cucumber Holothuria (Halodeima) inornata in two populations (Caleta de Campos, Michoacán 'CC' and Puerto Madero, Chiapas 'PM') in the southern coast of the Mexican Pacific by examining: intensity and duration of MGI, frequency of each gonadal developmental stage (GDS) through time, sexual asymmetry in GSI, sexual asymmetry in GDS, and adult sex ratio. We observed a trade-off between the intensity (%) and duration (months) of each sex's MGI: as intensity decreases, duration increases and conversely. The frequency of ripe and spawning stages was consistently higher in females than males. Sexual asymmetry in GSI was slightly female-biased in the PM population, but male-biased in the CC population. Sexual asymmetry in GDS showed a more recurrent sexual equality at PM than at CC. The adult sex ratio of each population did not differ significantly from unity, but showed a near-significant trend for male bias in the CC. Although H. inornata exhibited different MGI responses between males and females and more markedly in CC than in PM, it also showed a synchronized relation between its mass investment (GSI) and physiological investment (GDS), possibly reflecting an optimum reproductive strategy. Lastly, changes in GSI were not underpinned by changes in local temperature, but rather by regional temperature. [ABSTRACT FROM AUTHOR]

The coronavirus disease 2019 (COVID19) pandemic has left researchers scrambling to identify the humoral immune correlates of protection from COVID-19. To date, the antibody mediated correlates of virus neutralization have been extensively studied. However, the extent that non-neutralizing functions contribute to anti-viral responses are ill defined. In this study, we profiled the anti-spike antibody subtype/subclass responses, along with neutralization and antibody-dependent natural killer cell functions in 83 blood samples collected between 4 and 201 days post-symptoms onset from a cohort of COVID-19 outpatients. We observed heterogeneous humoral responses against the acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein. Overall, anti-spike profiles were characterized by a rapid rise of IgA and sustained IgG titers. In addition, strong antibody-mediated natural killer effector responses correlated with milder disease and being female. While higher neutralization profiles were observed in males along with increased severity. These results give an insight into the underlying function of antibodies beyond neutralization and suggest that antibody-mediated natural killer cell activity is a key function of the humoral response against the SARS-CoV-2 spike protein. [ABSTRACT FROM AUTHOR]

A study was conducted to characterize a Mexican Bacillus thuringiensis strain collection. B. thuringiensis strains were grown on a nutrient medium plane while the resulting cell lysate was centrifuged at 10,000 rpm. Protein analyses were then carried out using sodium dodecyl sulfate. Results indicated that the cryl genes were abundant in the Mexican strain collection. The strain collection also supported other cry genes such as lepidopteran-active cry1 genes and coleopteran-active cry3A, cry3Ba, and cry7A genes.

Background: New World Hantaviruses (NWHs) are the etiological agent underlying hantavirus cardiopulmonary syndrome (HCPS), a severe respiratory disease with high mortality rates in humans. In Panama, infections with Choclo Orthohantavirus (CHOV) cause a much milder illness characterized by higher seroprevalence and lower mortality rates. To date, the cytokine profiles and antibody responses associated with this milder form of HCPS have not been defined. Therefore, in this study, we examined immune serological profiles associated with CHOV infections. Methods: For this retrospective study, sera from fifteen individuals with acute CHOV-induced HCPS, were analyzed alongside sera from fifteen convalescent phase individuals and thirty-three asymptomatic, CHOV-seropositive individuals. Cytokine profiles were analyzed by multiplex immunoassay. Antibody subclasses, binding, and neutralization against CHOV-glycoprotein (CHOV-GP) were evaluated by ELISA, and flow cytometry. Results: High titers of IFNγ, IL-4, IL-8, and IL-10 serum cytokines were found in the acute individuals. Elevated IL-4 serum levels were found in convalescent and asymptomatic seropositive individuals. High titers of IgG1 subclass were observed across the three cohorts analyzed. Neutralizing antibody response against CHOV-GP was detectable in few acute individuals but was strong in both convalescent and asymptomatic seropositive individuals. Conclusion: A Th1/Th2 cytokine signature is characteristic during acute mild HCPS caused by CHOV infection. High expression of Th2 and IL-8 cytokines are correlated with clinical parameters in acute mild HCPS. In addition, a strong IL-4 signature is associated with different cohorts, including asymptomatic individuals. Furthermore, asymptomatic individuals presented high titers of neutralizing antibodies. [ABSTRACT FROM AUTHOR]

Objective: To study what women think about menopause treatments and assess their knowledge about them. To analyze adherence to treatment during COVID-19 confinement as a secondary objective.Methods: A multi-center cross-sectional observational study was conducted using a survey of 2500 women between January and June 2019. This was administered following a non-probability sampling procedure including women between 35 and 75 years. An extension study was conducted during the coronavirus pandemic, between March and June 2020.Results: The responses of 2355 surveyed women were analyzed. Of this sample, 42% knew about menopause hormone therapy (MHT). The most frequently identified indication was the treatment of hot flashes (65.6%). The MHT risks most frequently perceived were weight gain (24.2%) and breast cancer (21.7%); the main reason for rejecting MHT was a lack of information (96.1%). Comparative analyses were conducted according to age, menopausal status, type of menopause, place of residence, type of health care and level of education. During the coronavirus confinement period, 85 women using MHT were located, of which 84.7% continued it.Conclusions: Women hold certain false beliefs about menopause, and their knowledge of the available treatments is somewhat limited. Adherence to MHT during the COVID-19 confinement in Spain has been high. [ABSTRACT FROM AUTHOR]

Hantavirus cardiopulmonary syndrome (HCPS) caused by Andes orthohantavirus (ANDV) in South America is a public health threat due to the significant rate of mortality and the lack of a specific treatment. Interestingly, the virus does not produce cytopathic effect, thereby the strong antiviral immune response is suspected to contribute to pathogenesis, hence is important to understand the balance between protective and harmfully immunity. CD4+ T regulatory cells (Treg) are essential to control an exacerbated immune response. In human ANDV infection, little is known about CD4+ Treg cells, which may be involved in control immunopathology associated to the infection. In this report, we characterize the phenotype of memory CD4+ Tregs in a HCPS survivor's cohort. Based on the expression of CXCR3, CCR4, and CCR6, we identified different Th-like Treg populations in ANDV survival's PBMCs. In addition, the effect of ANDV-glycoprotein virus like particles (VLP) was determined. We demonstrated that memory CD4+ Treg from HCPS present a specific phenotype, showing higher frequency of PD-1 compared to healthy donors (HD). In addition, it was observed a decrease in the frequency of Th1-like memory CD4+ Treg in HCPS, important to highlight that this signature could be preserved even years after resolution of infection. Moreover, to gain insight in the mechanism involved, we evaluated whether ANDV-glycoprotein (GP) VLP could modulate CD4+ Treg. Interestingly, ANDV-GP VLP induced a decrease in the frequency of CXCR3 (Th1-like) and an increase in CCR4 (Th2-like) memory CD4+ Treg in both HD and HCPS PBMCs, indicating that ANDV-GP could specifically act over CXCR3 and CCR4 in CD4+ Treg. This report contributes to the study of human CD4+ Treg cells in ANDV infection. [ABSTRACT FROM AUTHOR]

Lolliguncula diomedeae is captured incidentally in the by-catch of the shrimp trawl fishery, however, there is little information about its life history. Therefore, data on reproductive indicators were collected in this study to evaluate the reproductive biology of L. diomedeae in the Gulf of Tehuantepec. A total of 1525 specimens, 1354 females with dorsal mantle length (ML) ranging from 18.9 to 90.3 mm and 171 males with 29.2 to 63.1 mm ML. The sex ratio was 8:1 females/males, with two reproductive peaks, one more intense in November and the other moderate in May. The first maturity size (L50) for females was 66.65 and 40.79 mm in males. The histological analysis showed five stages of development: pre-vitellogenesis, vitellogenesis, post-vitellogenesis, spawning, and post-spawning; with the simultaneous presence of oocytes at different stages. In relation to the results found and the consistent presence of post-ovulatory follicles and oocytes of different sizes and developments, we can infer that L. diomedeae is a multiple reproducer, as it spawns in batches in different periods of time in the study area, which can be considered as an adaptation strategy in response to regional environmental changes. [ABSTRACT FROM AUTHOR]

Here we aim to describe early mutational events across samples from publicly available SARS-CoV-2 sequences from the sequence read archive and GenBank repositories. Up until 27 March 2020, we downloaded 50 illumina datasets, mostly from China, USA (WA State) and Australia (VIC). A total of 30 datasets (60%) contain at least a single founder mutation and most of the variants are missense (over 63%). Five-point mutations with clonal (founder) effect were found in USA next-generation sequencing samples. Sequencing samples from North America in GenBank (22 April 2020) present this signature with up to 39% allele frequencies among samples (n = 1,359). Australian variant signatures were more diverse than USA samples, but still, clonal events were found in these samples. Mutations in the helicase, encoded by the ORF1ab gene in SARS-CoV-2 were predominant, among others, suggesting that these regions are actively evolving. Finally, we firmly urge that primer sets for diagnosis be carefully designed, since rapidly occurring variants would affect the performance of the reverse transcribed quantitative PCR (RT-qPCR) based viral testing. [ABSTRACT FROM AUTHOR]

The isolation of a Mexican strain (Mor4.1) that is identified as a Serratia entomophila strain, which is pathogenic for several species of scarab larvae, is described. The identification of a putative Serratia entomophila bacterial strain pathogenic to Mexican 'white grubs' is very important for the development of biotechnological strategies to reduce crop damage by this important complex of soil-dwelling pests.