HST/NICMOS Paschen-alpha Survey of the Galactic Center: Overview

We have recently carried out the first wide-field hydrogen Paschen-alpha line imaging survey of the Galactic Center (GC), using the NICMOS instrument aboard the Hubble Space Telescope. The survey maps out a region of 2253 pc^2 around the central supermassive black hole (Sgr A*) in the 1.87 and 1.90 Micron narrow bands with a spatial resolution of 0.01 pc at a distance of 8 kpc. Here we present an overview of the observations, data reduction, preliminary results, and potential scientific implications, as well as a description of the rationale and design of the survey. We have produced mosaic maps of the Paschen-alpha line and continuum emission, giving an unprecedentedly high resolution and high sensitivity panoramic view of stars and photo-ionized gas in the nuclear environment of the Galaxy. We detect a significant number of previously undetected stars with Paschen-alpha in emission. They are most likely massive stars with strong winds, as confirmed by our initial follow-up spectroscopic observations. About half of the newly detected massive stars are found outside the known clusters (Arches, Quintuplet, and Central). Many previously known diffuse thermal features are now resolved into arrays of intriguingly fine linear filaments indicating a profound role of magnetic fields in sculpting the gas. The bright spiral-like Paschen-alpha emission around Sgr A* is seen to be well confined within the known dusty torus. In the directions roughly perpendicular to it, we further detect faint, diffuse Paschen-alpha emission features, which, like earlier radio images, suggest an outflow from the structure. In addition, we detect various compact Paschen-alpha nebulae, probably tracing the accretion and/or ejection of stars at various evolutionary stages.Comment: accepted for publication in MNRAS; a version of higher resolution images may be found at http://www.astro.umass.edu/~wqd/papers/hst/paper1.pd

Ethnic differences in body composition and somatotype in Mapuche and non-Mapuche school children from Temuco-Chile

Los cambios culturales y demográficos en la etnia Mapuche chilena, han generado modificaciones en estilos de vida y la estructura morfofuncional de su población, incentivando de esta forma el estudio del estado de salud en jóvenes chilenos. El objetivo de este estudio fue analizar las diferencias en composición corporal y somatotipo entre niños Mapuche y no-Mapuche de la Comuna de Temuco en Chile. Participaron 122 niños Mapuche y 146 niños no-Mapuche entre 10 y 13 años. Se recogieron medidas de peso, talla; pliegues cutáneos y diámetros óseos; siguiendo el protocolo de la Sociedad Internacional para el desarrollo de la cineantropometría (ISAK). Se determinó el índice de masa corporal (IMC), estado nutricional, grasa corporal total y somatotipo (endomorfía, mesomorfía y ectomorfía). Los resultados indican que los niños Mapuche de 10 años presentaron valores menores de IMC (p0,01), grasa corporal total (p 0,001), así como de endomorfia y mesomorfia (p0,01) respecto a los no-Mapuche. Los niños Mapuche de 11-12 años presentaron valores menores de grasa corporal total (p0,01) y de endomorfia y ectomorfia (p0,05), comparados con los no-Mapuche. Los niños Mapuches de 13 años presentaron valores menores de grasa corporal total (p0,001) y de endomorfia y ectomorfía (p0,01) que el no-Mapuche. Los escolares Mapuches tienen menor grasa corporal que los niños no-Mapuche, el somatotipo predominante en la etnia Mapuche es el mesomórfico, observándose un componente endomórfico menor cuanto mayor es la edad. Son necesarias políticas de salud pública en los jóvenes, fundamentalmente educativa, para garantizar niveles adecuados de calidad de vida en ambas poblaciones Mapuches y no-Mapuche.The cultural and demographic development of modern society has also affected the Mapuche ethnia and has influenced changes in lifestyles and in the morphofunctional structure of the population, particularly in young people. The purpose of this study was to determine differences in body composition and somatotype between Mapuche and non-Mapuche children from Temuco, Chile. A total of 122 Mapuche and 146 non-Mapuche children between 10 and 13 years old participated in the study. The measurements included were weight, height, skinfold thickness of triceps, subscapularis, supraspinatus and calf; perimeters of contracted and relaxed arm, waist and calf circumference; and humeral and femoral diameters, all following the procedures reference manual (ISAK). Several indexes were calculated: Body Mass Index (BMI), weight status (underweight, normoweight, overweight, obesity), total body fat (fat mass, percentage of fat mass and percentage of fat mass >20% of obesity) and finally, somatotype (endomorph, ectomorph, mesomorph). Ten year-old Mapuche children had lower values for BMI (p 0,01), total body fat (p0.001), and endomorphic and mesomorphic values (p0.01), compared to non Mapuche children. Mapuche children of 11-12 years of age had lower values for total body fat (p0.01), and endomorphic and ectomorphic values (p0.05), compared to non-Mapuche children. Thirteen year-old Mapuche children had lower values for total body fat (p0.001), and endomorphic and ectomorphic values (p0.01), compared to non-Mapuche children. Mapuche children had lower fat mass than non-Mapuche children, and the main somatotype among Mapuche children is mesomorphic with a reduction of the endomorphic component with increasing age. Public policy for youth is required, mainly educational, to guarantee appropriate levels of quality of life for both Mapuche and non-Mapuche populations

Environmental drivers of aquatic macrophyte communities in southern tropical African rivers:Zambia as a case study

The first-ever extensive macrophyte survey of Zambian rivers and associated floodplain waterbodies, conducted during 2006–2012, collected 271 samples from 228 sites, mainly located in five freshwater ecoregions of the world primarily represented in Zambia. The results supported the hypothesis that variation in macrophyte community structure (measured as species composition and diversity) in southern tropical African river systems, using Zambia as a case study area, is driven primarily by geographical variation in water physico-chemical conditions. In total, 335 macrophyte taxa were recorded, and a chronological cumulative species records curve for the dataset showed no sign of asymptoting: clearly many additional macrophyte species remain to be found in Zambian rivers. Emergent macrophytes were predominant (236 taxa), together with 26 floating and 73 submerged taxa. Several species were rare in a regional or international context, including two IUCN Red Data List species: Aponogeton rehmanii and Nymphaea divaricata. Ordination and classification analysis of the data found little evidence for temporal change in vegetation, at repeatedly-sampled sites, but strong evidence for the existence of seven groups of samples from geographically-varied study sites. These supported differing sets of vegetation (with eight species assemblages present in the sample-groups) and showed substantial inter-group differences in both macrophyte alpha-diversity, and geographically-varying physico-chemical parameters. The evidence suggested that the main environmental drivers of macrophyte community composition and diversity were altitude, stream order, shade, pH, alkalinity, NO3-N, and underwater light availability, while PO4-P showed slightly lower, but still significant variation between sample-groups

p53 connects tumorigenesis and reprogramming to pluripotency

The tumor suppressor gene p53 prevents the initiation of tumor formation by inducing cell cycle arrest, senescence, DNA repair, and apoptosis. Recently, the absence or mutation of p53 was described to facilitate nuclear reprogramming. These findings suggest an influence of p53 on the de-differentiation process, and highlight the similarities between induction of pluripotency and tumor formation

Niche-breadth of freshwater macrophytes occurring in tropical southern African rivers predicts species global latitudinal range

The study tested the hypothesis that measurement, using multivariate Principal Components Analy-sis (PCA), of the niche-breadth of river macrophyte species in southern tropical Africa, may predicttheir larger-scale biogeographical range. Two measures of niche-breadth were calculated for 44 riverinemacrophyte species, from 20 families commonly occurring in Zambia, using an approach based on PCAordination with 16 bio-physico-chemical input variables. These included altitude, stream order, streamflow, pH, conductivity and soluble reactive phosphate concentration (SRP). In the absence of additionalchemical water quality data for Zambian rivers, invertebrate-based measures of general water qualitywere also used. These were benthic macroinvertebrate Average Score per Taxon (ASPT), and individualabundance of nine macroinvertebrate families with differing water quality tolerance, indicated by theirSensitivity Weightings within the Zambian Invertebrate Scoring System (ZISS). Macrophyte large-scalelatitudinal range was derived from world geopositional records held by online databases, and additionalrecords held by the authors. The two niche-breadth metrics divided the species into narrow-niche andintermediate/broad-niche categories, showing significant variation (from one or both of correlation andANOVA test outcomes) in altitude, stream flow, conductivity, SRP, pH and ASPT, but not stream order.Macrophyte alpha-diversity (as a measure of number of individual niches co-existing per habitat) showedno significant relationship with individual species niche-breadth. Narrow-niche species included a higherproportion of Afrotropical endemics than did species with broader niche size. There were significant pre-dictive relationships between macrophyte niche-breadth and latitudinal range of the target species atglobal and Afrotropical scales, but not for the Neotropics.Fil: Kennedy, Michael. University Of Aberdeen; Reino UnidoFil: Lang, Pauline. University of Glasgow; Reino UnidoFil: Tapia Grimaldo, Julissa. University of Glasgow; Reino UnidoFil: Varandas Martins, Sara. University of Glasgow; Reino UnidoFil: Bruce, Alannah. University of Glasgow; Reino UnidoFil: Moore, Isabel. University of Glasgow; Reino UnidoFil: Taubert, Rebeca. University of Glasgow; Reino UnidoFil: Macleod-Nolan, Chantal. University of Glasgow; Reino UnidoFil: McWaters, Stephanie. University of Glasgow; Reino UnidoFil: Briggs, John. University of Glasgow; Reino UnidoFil: Lowe, Steve. University of Glasgow; Reino UnidoFil: Saili, Kochelani. University Of Zambia;Fil: SICHINGABULA, Henry. University Of Zambia;Fil: Dallas, Helen. Nelson Mandela Metropolitan University, Sudafrica; SudáfricaFil: Morrison, Sean. University of Glasgow; Reino UnidoFil: Franceschini, Maria Celeste. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; ArgentinaFil: Willems, Frank. The Kasanka Trust; ZambiaFil: Bottino, Flavia. Universidad Federal de San Carlos; BrasilFil: MURPHY Kevin. University of Glasgow; Reino Unid

Utilizing international networks for accelerating research and learning in transformational sustainability science

A promising approach for addressing sustainability problems is to recognize the unique conditions of a particular place, such as problem features and solution capabilities, and adopt and adapt solutions developed at other places around the world. Therefore, research and teaching in international networks becomes critical, as it allows for accelerating learning by sharing problem understandings, successful solutions, and important contextual considerations. This article identifies eight distinct types of research and teaching collaborations in international networks that can support such accelerated learning. The four research types are, with increasing intensity of collaboration: (1) solution adoption; (2) solution consultation; (3) joint research on different problems; and (4) joint research on similar problems. The four teaching types are, with increasing intensity of collaboration: (1) adopted course; (2) course with visiting faculty; (3) joint course with traveling faculty; and (4) joint course with traveling students. The typology is illustrated by extending existing research and teaching projects on urban sustainability in the International Network of Programs in Sustainability, with partner universities from Europe, North America, Asia, and Africa. The article concludes with challenges and strategies for extending individual projects into collaborations in international networks.Postprint (author's final draft

Improved Xenobiotic Metabolism and Reduced Susceptibility to Cancer in Gluten-Sensitive Macaques upon Introduction of a Gluten-Free Diet

A non-human primate (NHP) model of gluten sensitivity was employed to study the gene perturbations associated with dietary gluten changes in small intestinal tissues from gluten-sensitive rhesus macaques (Macaca mulatta).Stages of remission and relapse were accomplished in gluten-sensitive animals by administration of gluten-free (GFD) and gluten-containing (GD) diets, as described previously. Pin-head-sized biopsies, obtained non-invasively by pediatric endoscope from duodenum while on GFD or GD, were used for preparation of total RNA and gene profiling, using the commercial Rhesus Macaque Microarray (Agilent Technologies),targeting expression of over 20,000 genes.When compared with normal healthy control, gluten-sensitive macaques showed differential gene expressions induced by GD. While observed gene perturbations were classified into one of 12 overlapping categories--cancer, metabolism, digestive tract function, immune response, cell growth, signal transduction, autoimmunity, detoxification of xenobiotics, apoptosis, actin-collagen deposition, neuronal and unknown function--this study focused on cancer-related gene networks such as cytochrome P450 family (detoxification function) and actin-collagen-matrix metalloproteinases (MMP) genes.A loss of detoxification function paralleled with necessity to metabolize carcinogens was revealed in gluten-sensitive animals while on GD. An increase in cancer-promoting factors and a simultaneous decrease in cancer-preventing factors associated with altered expression of actin-collagen-MMP gene network were noted. In addition, gluten-sensitive macaques showed reduced number of differentially expressed genes including the cancer-associated ones upon withdrawal of dietary gluten. Taken together, these findings indicate potentially expanded utility of gluten-sensitive rhesus macaques in cancer research