The MeerKAT Galaxy Cluster Legacy Survey: I. Survey overview and highlights

Please abstract in the article.The South African Radio Astronomy Observatory (SARAO), the National Research Foundation (NRF), the National Radio Astronomy Observatory, US National Science Foundation, the South African Research Chairs Initiative of the DSI/NRF, the SARAO HCD programme, the South African Research Chairs Initiative of the Department of Science and Innovation.http://www.aanda.orghj2022Physic

Mapping density, diversity and species-richness of the Amazon tree flora

Using 2.046 botanically-inventoried tree plots across the largest tropical forest on Earth, we mapped tree species-diversity and tree species-richness at 0.1-degree resolution, and investigated drivers for diversity and richness. Using only location, stratified by forest type, as predictor, our spatial model, to the best of our knowledge, provides the most accurate map of tree diversity in Amazonia to date, explaining approximately 70% of the tree diversity and species-richness. Large soil-forest combinations determine a significant percentage of the variation in tree species-richness and tree alpha-diversity in Amazonian forest-plots. We suggest that the size and fragmentation of these systems drive their large-scale diversity patterns and hence local diversity. A model not using location but cumulative water deficit, tree density, and temperature seasonality explains 47% of the tree species-richness in the terra-firme forest in Amazonia. Over large areas across Amazonia, residuals of this relationship are small and poorly spatially structured, suggesting that much of the residual variation may be local. The Guyana Shield area has consistently negative residuals, showing that this area has lower tree species-richness than expected by our models. We provide extensive plot meta-data, including tree density, tree alpha-diversity and tree species-richness results and gridded maps at 0.1-degree resolution

The stellar mass-size relation for the most isolated galaxies in the local universe

Disentangling processes governing the formation and evolution of galaxies is a fundamental challenge in extragalactic research. In this sense, the current belief that galaxies grow by the action of minor mergers makes the study of the stellar mass-size relation in different environments an important tool for distinguishing effects of internal and external processes. The aim of this work is to study the effects of environment on the growth in size of galaxies. As part of Analysis of the Interstellar Medium of Isolated GAlaxies (AMIGA project), we examine the stellar mass-size relation for a sample of the most isolated galaxies in the local Universe interpreted as stellar systems where evolution has been mainly governed by internal processes. Effects of environment on the stellar mass-size relation are evaluated by comparing our results with samples of less isolated early- and late-type galaxies, as well as, for the first time, different spiral subtypes. Stellar masses in our sample were derived by fitting the SED of each galaxy with KCORRECT. We used two different size estimators, the half-light radius obtained with SEXTRACTOR and the effective radius calculated by fitting a S'ersic profile to the i-band image of each galaxy using GALFIT. We found good agreement between those size estimators when the S'ersic index fell in the range 2.5 < n < 4.5 and 0.5 < n < 2.5 for (visually classified) early- and late-type galaxies, respectively. We find no difference in the stellar mass-size relation for very isolated and less isolated early-type galaxies. We find that late-type isolated galaxies are ~1.2 times larger than less isolated objects with similar mass. Isolated galaxies and comparison samples were divided into six morphological ranges (E/S0, Spirals, Sb, Sbc, Sc and Scd-Sdm) and five stellar mass bins between log (M*) = [9,11.5]. In all cases, the relation is better defined and has less scatter for the isolated galaxies. We find that as the morphological type becomes later the galaxy size (for a fixed stellar mass range) becomes larger. For the lowest stellar mass bins log (M*) = [9,10], we find good agreement between sizes of AMIGA and comparison spirals (both mostly composed of Scd-Sdm types). The isolated spiral galaxies in the high stellar mass bins log (M*) = [10,11] tend to be larger than less isolated galaxies. This difference in size is found for all spiral subtypes and becomes larger when we compare fully isolated galaxies with galaxies having two or more satellites (neighbours within 3 mag of difference at a distance less than 250 kpc from the galaxy). Our results suggest that massive spiral galaxies located in low-density environments, both in terms of major companions and satellites, have larger sizes than samples of less isolated galaxies. Hence, the environment has played a role in the growth in size of massive spiral galaxies. © 2013 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society.This work has been supported by Grant AYA2011-30491-C02-01 co-financed by MICINN and FEDER funds, and the Junta de Andalucia (Spain) grants P08-FQM-4205 and TIC-114.Peer Reviewe

Positive correlation of serum leptin with estradiol levels in patients with polycystic ovary syndrome

Patients with polycystic ovary syndrome (PCOS) usually are obese, insulin resistant and hyperinsulinemic. The known association between leptin, obesity andinsulin action suggests that leptin may have a role in PCOS but this has only been addressed peripherally. This study was designed to assess the relationship between serum leptin and the anthropometric, metabolic and endocrine variables of obese (body mass index, BMI ³30 kg/m²) and non-obese (BMI <30 kg/m²) PCOS patients. Twenty-eight PCOS patients and 24 control women subdivided into obese and non-obese groups were evaluated. Leptin, androgens, lipids, gonadotrophins and insulin-glucose response to the oral glucose tolerance test were measured by radioimmunoassay in all participants. The assays were done all in one time. The areas under the insulin curve (AUC-I) and the glycemia curve were calculated to identify patients with insulin resistance. Mean leptin levels were not significantly higher in patients with PCOS compared to the control group (21.2 ± 10.2 vs 27.3 ± 12.4 ng/ml). Leptin levels were found to be significantly higher in the obese subgroups both in patients with PCOS (26.9 ± 9.3 vs 14.1 ± 7.0 ng/ml) and in the control group (37.3 ± 15.5 vs 12.9 ± 5.8 ng/ml). The leptin of the PCOS group was correlated with BMI (r = 0.74; P < 0.0001) and estradiol (r = 0.48; P < 0.008) and tended to be correlated with the AUC-I (r = 0.36; P = 0.05). Of the parameters which showed a correlation with leptin in PCOS, only estradiol and probably insulinemia (AUC-I) did not show a significant correlation with BMI, suggesting that the other parameters were correlated with leptin due to their correlation with BMI. Estradiol correlated with leptin in PCOS patients regardless of their weight

Clast shape-fabric analysis: A comprehensive and efficient methodology to measure particle-orientation data in solid and loose volcaniclastic deposits

Fabric analysis is essential for understanding the evolution of volcaniclastic deposits. Here we present a comprehensive and efficient methodology, called “Clast shape-fabric analysis,” which is part of the Quantitative Textural Analysis (QTA). This methodology combines high-resolution image analysis techniques with geospatial data processing tools.The fabric of a deposit refers to the three-dimensional orientation of the particles with respect to space, where the degree of iso-orientation of the major axes of the particles is taken into account. The process begins with the collection of oriented samples in the field. Then, in the laboratory, the samples are processed to obtain high-resolution images. The final stage involves the analysis of these images using the FabricS program, which combines image processing techniques and circular statistics.An application of the method was made at the Joya Honda Maar in Mexico, where shape-fabric analysis was used to identify the emission centers of pyroclastic materials.In summary, the “Clast shape-fabric analysis” is a reliable, low-cost and high-potential methodology that can be applied in several geoscientific disciplines and other areas of scientific research. • New Methodology for shape-fabric analysis is presented. • The methodology involves field work, laboratory work and image analysis. • Identification of particle orientations in volcaniclastic deposits

Antibody responses to

This study evaluates the differences in host immune responses to defined plasmodial antigens in four geographically different regions in which malaria is endemic. Sera from 527 individuals were tested for the presence of antibodies specific for three types of plasmodial antigen : liver-stage antigen (LSA-1), blood-stage antigen (SPF 70) and circumsporozoite (CS) antigen (NANP)4. The individuals taking part in the study comprised : patients with transfusional malaria due to Plasmodium falciparum or P. vivax; non-immune migrants residing in an endemic area in Rondônia; Amazonian Indians from the states of Para (Xingu PA) and Mato Grosso (Xingu MT); people living in a hyperendemic area in Africa (Burkina-Faso); and controls that had never been to a malaria endemic area. None of the transfusional sera displayed antibodies against sporozoite or to liver stage antigen, although 80% of the P. falciparum transfusional malaria sera contained IgG antibodies against the blood-stage peptide. A low percentage of Indians from Xingu PA and of non-immune migrants displayed antibodies against liver-stage (27% and 17%) and sporozoite (11% and 12%) peptides, although a greater frequency of antibodies against blood-stage peptide (50% and 49%) was observed in both cases. Indians from Xingu MT exhibited a greater frequency of antibodies against liver, sporozoite and blood-stage peptides (45%, 50% and 58%). Only hyperimmune African individuals exhibited higher percentages of antibodies against liver- (64%) and blood-stage antigens (87%), contrasting with a low frequency of antibodies against the CS repeat (33%). Taken together, the present data confirm that Rondonian migrants and Indians from Xingu PA constitute populations with limited exposure and immunity to P. falciparum malaria infection and conversely, Xingu MT Indians and Africans have been more exposed to malaria infection. In conclusion this study indicates that the immune response to these malaria parasite peptides can be used to assess malaria transmission in epidemiological surveys