3,687 research outputs found

    Bacterial Active Community Cycling in Response to Solar Radiation and Their Influence on Nutrient Changes in a High-Altitude Wetland

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    IndexaciĂłn: Web of Science; Scopus.Microbial communities inhabiting high-altitude spring ecosystems are subjected to extreme changes in solar irradiance and temperature throughout the diel cycle. Here, using 16S rRNA gene tag pyrosequencing (cDNA) we determined the composition of actively transcribing bacteria from spring waters experimentally exposed through the day (morning, noon, and afternoon) to variable levels of solar radiation and light quality, and evaluated their influence on nutrient recycling. Solar irradiance, temperature, and changes in nutrient dynamics were associated with changes in the active bacterial community structure, predominantly by Cyanobacteria, Verrucomicrobia, Proteobacteria, and 35 other Phyla, including the recently described Candidate Phyla Radiation (e.g., Parcubacteria, Gracilibacteria, OP3, TM6, SR1). Diversity increased at noon, when the highest irradiances were measured (3.3-3.9 H', 1125 W m(-2)) compared to morning and afternoon (0.6-2.8 H'). This shift was associated with a decrease in the contribution to pyrolibraries by Cyanobacteria and an increase of Proteobacteria and other initially low frequently and rare bacteria phyla (< 0.5%) in the pyrolibraries. A potential increase in the activity of Cyanobacteria and other phototrophic groups, e.g., Rhodobacterales, was observed and associated with UVR, suggesting the presence of photo activated repair mechanisms to resist high levels of solar radiation. In addition, the percentage contribution of cyanobacterial sequences in the afternoon was similar to those recorded in the morning. The shifts in the contribution by Cyanobacteria also influenced the rate of change in nitrate, nitrite, and phosphate, highlighted by a high level of nitrate accumulation during hours of high radiation and temperature associated with nitrifying bacteria activity. We did not detect ammonia or nitrite oxidizing bacteria in situ, but both functional groups (Nitrosomona and Nitrospira) appeared mainly in pyrolibraries generated from dark incubations. In total, our results reveal that both the structure and the diversity of the active bacteria community was extremely dynamic through the day, and showed marked shifts in composition that influenced nutrient recycling, highlighting how abiotic variation affects potential ecosystem functioning.http://journal.frontiersin.org/article/10.3389/fmicb.2016.01823/ful

    Women, Health and Aging: Building a Statewide Movement

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    Provides an overview of current policy and program environments that affect the state's most vulnerable elder population, and considers some effective strategies to address the growing needs of older persons in California

    Restoring Color-magnitude Diagrams with the Richardson-Lucy Algorithm

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    We present an application of the Richardson-Lucy algorithm to the analysis of color-magnitude diagrams by converting the CMD into an image and using a restoring point spread function function ({\it psf}) derived from the known, often complex, sources of error. We show numerical experiments that demonstrate good recovery of the original image and establish convergence rates for ideal cases with single gaussian uncertainties and poisson noise using a χ2\chi^2 statistic. About 30-50 iterations suffice. As an application, we show the results for a particular case, the Hipparcos sample of the solar neighborhood where the uncertainties are mainly due to parallax which we model with a composite weighted gaussian using the observed error distributions. The resulting psf has a slightly narrower core and broader wings than a single gaussian. The reddening and photometric errors are considerably reduced by restricting the sample to within 80 pc and to M_V \leq 3.5. We find that the recovered image, which has a narrower, better defined main sequence and a more clearly defined red giant clump, can be used as input to stellar evolution modeling of the star formation rate in the solar vicinity and, with more contributing uncertainties taken into account, for general Galactic and extragalactic structure and population studies.Comment: Accepted for publication in Astronomy and Astrophysics, main journa

    Ep-CAM (MOC-31) expression in tooth germ and ameloblastoma

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    Ep-CAM, a transmembrane glycoprotein expressed in most epithelium in normal conditions, has diverse roles in these tissues, including in cell adhesion, proliferation, differentiation, cell cycle regulation, migration and intracellular signaling. It is also over-expressed in most malignant neoplasia, participating in the initiation, progression, and metastatic dissemination of the tumor. The expression and roles of this protein in oral neoplasia, particularly in odontogenic tumors, remain unestablished. The objective of this study consisted in analyzing the expression of this protein in ameloblastoma and tooth germ

    The Jak2 Pathway Is Activated In Idiopathic Pulmonary Fibrosis

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    Background: Idiopathic pulmonary fibrosis (IPF) is the most rapidly progressive and fatal fibrotic disorder, with no curative therapies. The signal transducer and activator of transcription 3 (STAT3) protein is activated in lung fibroblasts and alveolar type II cells (ATII), thereby contributing to lung fibrosis in IPF. Although activation of Janus kinase 2 (JAK2) has been implicated in proliferative disorders, its role in IPF is unknown. The aim of this study was to analyze JAK2 activation in IPF, and to determine whether JAK2/STAT3 inhibition is a potential therapeutic strategy for this disease. Methods and results: JAK2/p-JAK2 and STAT3/pSTAT3 expression was evaluated using quantitative real time-PCR, western blotting, and immunohistochemistry. Compared to human healthy lung tissue (n = 10) both proteins were upregulated in the lung tissue of IPF patients (n = 12). Stimulating primary ATII and lung fibroblasts with transforming growth factor beta 1 or interleukin (IL)-6/IL-13 activated JAK2 and STAT3, inducing epithelial to mesenchymal and fibroblast to myofibroblast transitions. Dual p-JAK2/p-STAT3 inhibition with JSI-124 or silencing of JAK2 and STAT3 genes suppressed ATII and the fibroblast to myofibroblast transition, with greater effects than the sum of those obtained using JAK2 or STAT3 inhibitors individually. Dual rather than single inhibition was also more effective for inhibiting fibroblast migration, preventing increases in fibroblast senescence and Bcl-2 expression, and ameliorating impaired autophagy. In rats administered JSI-124, a dual inhibitor of p-JAK2/p-STAT3, at a dose of 1 mg/kg/day, bleomycin-induced lung fibrosis was reduced and collagen deposition in the lung was inhibited, as were JAK2 and STAT3 activation and several markers of fibrosis, autophagy, senescence, and anti-apoptosis. Conclusions: JAK2 and STAT3 are activated in IPF, and their dual inhibition may be an attractive strategy for treating this disease

    Selected topics on Hadrons in Nuclei

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    In this talk we report on selected topics on hadrons in nuclei. The first topic is the renormalization of the width of the Λ(1520)\Lambda(1520) in a nuclear medium. This is followed by a short update of the situation of the ω\omega in the medium. The investigation of the properties of Kˉ\bar{K} in the nuclear medium from the study of the (Kflight,p)(K_{flight},p) reaction is also addressed, as well as properties of X,Y,Z charmed and hidden charm resonances in a nuclear medium. Finally we address the novel issue of multimeson states.Comment: Talk at the International Nuclear Physics Conference, Vancouver, July 201

    Hydroxylated phosphines as ligands for chalcogenide clusters: Self assembly, transformations and stabilization

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    © 2017 IUPAC & De Gruyter.This contribution is a documentation of recent advances in the chemistry of chalcogenide polynuclear transition metal complexes coordinated with mono-and di-phosphines functionalized with hydroxo groups. A survey of complexes containing tris(hydroxymethyl)phosphine (THP) is presented. The influence of the alkyl chain in bidentate phosphines, bearing the P-(CH2)x-OH arms, is also analyzed. Finally, isolation and structure elucidation of the complexes with HP(OH)2, P(OH)3, As(OH)3, PhP(OH)2, stabilized by coordination to Ni(0) and Pd(0) centers embedded into chalcogenide clusters, is discussed

    Plasma Non-Enzymatic Antioxidant Capacity (NEAC) in Relation to Dietary NEAC, Nutrient Antioxidants and Inflammation-Related Biomarkers

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    The results presented in this article constitute part of the C.J. Carrión-García’s Doctoral Thesis performed in the Nutrition and Food Science Doctorate Program of the University of Granada.(1) Background: Little is known about the interlinkages between dietary and plasma non-enzymatic antioxidant capacity (D-NEAC and P-NEAC, respectively) and the body’s antioxidant and inflammation response. Our aim was to explore these associations in 210 participants from two Spanish European Prospective Investigation into Cancer and Nutrition (EPIC) centers. (2) Methods: D-NEAC was estimated using published NEAC values in food. P-NEAC and total polyphenols (TP) were quantified by FRAP (ferric-reducing antioxidant power), TRAP (total radical-trapping antioxidant parameter), TEAC-ABTS (trolox equivalent antioxidant capacity-Azino Bis Thiazoline Sulfonic), ORAC (oxygen radical absorbance capacity) and Folin–Ciocalteu assays. Nutrient antioxidants (carotenes, α-tocopherol, ascorbic acid, retinol, uric acid, Q9 and Q10 coenzymes) and inflammation markers (IL-6, IL-8, CRP, TNF-α, PAI-I, resistin and adiponectin) were also analyzed. Spearman correlation and linear regression analyses were performed in association analyses. Analyses were stratified by covariates and groups were defined using cluster analysis. (3) Results: P-FRAP was correlated with D-NEAC, and significantly associated with P-NEAC in multivariate adjusted models. P-FRAP levels were also significantly associated with plasma antioxidants (log2 scale: TP β = 0.26; ascorbic acid β = 0.03; retinol β = 0.08; α-tocopherol β = 0.05; carotenes β = 0.02; Q10 β = 0.06; uric acid β = 0.25), though not with inflammation-related biomarkers. Different profiles of individuals with varying levels of P-NEAC and biomarkers were found. (4) Conclusions: P-NEAC levels were to some extent associated with D-NEAC and plasma antioxidants, yet not associated with inflammation response.This research was co-funded by the Health Research Found (FIS), Acción Estratégica en Salud (AES), of the Spanish Ministry of Economy and Competitiveness, grant number PI12/00002, and the European Regional Development Fund (ERDF)

    An Investigative, Cooperative Learning Approach for General Chemistry Laboratories

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    The integration of research and education is an essential component of our university’s teaching philosophy. Recently, we made a curricular revision to facilitate such an approach in the General Chemistry Laboratory, to teach students that investigative approaches are at the core of sciences. The curriculum revision included new interdisciplinary experiments and a research project. Investigative, peer review, and cooperative learning strategies were introduced to enhance student learning and engagement. An environment in which students can analyze results within a laboratory session and reach comprehensive and quantitative conclusions was encouraged. To assess our results, students completed questionnaires, evaluated their peers and themselves. Instructors evaluated students through written reports, oral presentations, pre- and post test, a practical exam and a final exam. Assessments of the learning outcomes were performed to determine the level of research skills development, the improvement in laboratory techniques, and depth in analysis of concepts. The experimental designs, implementation of results, and comparisons of student performances using traditional approaches are presented
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