812 research outputs found

    N-(4-Bromo­phen­yl)-2-(2-thien­yl)acetamide

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    The thienyl ring in the title compound, C12H10BrNOS, is disordered over two diagonally opposite positions, the major component having a site-occupancy factor of 0.660 (5). The mol­ecule is twisted as evidenced by the dihedral angles of 70.0 (4) and 70.5 (6)° formed between the benzene ring and the two orientations of the disordered thio­phene ring. Linear supra­molecular chains along the a axis are found in the crystal structure through the agency of N—H⋯O hydrogen bonding

    Antimicrobial and Photoantimicrobial Activities of Chitosan/CNPPV Nanocomposites

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    Multidrug-resistant bacteria represent a global health and economic burden that urgently calls for new technologies to combat bacterial antimicrobial resistance. Here, we developed novel nanocomposites (NCPs) based on chitosan that display different degrees of acetylation (DAs), and conjugated polymer cyano-substituted poly(p-phenylene vinylene) (CNPPV) as an alternative approach to inactivate Gram-negative (E. coli) and Gram-positive (S. aureus) bacteria. Chitosan's structure was confirmed through FT-Raman spectroscopy. Bactericidal and photobactericidal activities of NCPs were tested under dark and blue-light irradiation conditions, respectively. Hydrodynamic size and aqueous stability were determined by DLS, zeta potential (ZP) and time-domain NMR. TEM micrographs of NCPs were obtained, and their capacity of generating reactive oxygen species (ROS) under blue illumination was also characterized. Meaningful variations on ZP and relaxation time T2 confirmed successful physical attachment of chitosan/CNPPV. All NCPs exhibited a similar and shrunken spherical shape according to TEM. A lower DA is responsible for driving higher bactericidal performance alongside the synergistic effect from CNPPV, lower nanosized distribution profile and higher positive charged surface. ROS production was proportionally found in NCPs with and without CNPPV by decreasing the DA, leading to a remarkable photobactericidal effect under blue-light irradiation. Overall, our findings indicate that chitosan/CNPPV NCPs may constitute a valuable asset for the development of innovative strategies for inactivation and/or photoinactivation of bacteria. Keywords: photoantimicrobial activity; blue-light irradiation; chitosan; CNPPV; nanocomposites; E. coli; S. aureu

    Apathy and functional disability in behavioral variant frontotemporal dementia

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    Background Behavioral variant frontotemporal dementia (bvFTD) has profound consequences on patients and their families. In this multicenter study, we investigated the contribution of cognitive and neuropsychiatric factors to everyday function at different levels of overall functional impairment. Methods In a retrospective cross-sectional study, 109 patients with bvFTD from 4 specialist frontotemporal dementia centers (Australia, England, India, and Brazil) were included. The measures administered evaluated everyday function (Disability Assessment for Dementia [DAD]), dementia staging (Clinical Dementia Rating [CDR]), general cognition (Addenbrooke’s Cognitive Examination–revised [ACE-R]), and neuropsychiatric symptoms (Neuropsychiatric Inventory [NPI]). Patients were then subdivided according to functional impairment on the DAD into mild, moderate, severe, and very severe subgroups. Three separate multiple linear regression analyses were run, where (1) total DAD, (2) basic activities of daily living (BADL), and (3) instrumental activities of daily living (IADL) scores were dependent variables; ACE-R total score and selected NPI domains (agitation/aggression, euphoria, apathy, disinhibition, irritability, aberrant motor behavior) were used as independent variables. Age, sex, education, and country of origin were controlled for in the analyses. Results Cognitive deficits were similar across the mild, moderate, and severe subgroups but significantly worse in the very severe subgroup. NPI domain scores (agitation/aggression, euphoria, apathy, disinhibition, irritability, aberrant motor behavior) did not differ across the DAD subgroups. In the multiple regression analyses, a model including ACE-R and NPI apathy explained 32.5% of the variance for total DAD scores. For IADL, 35.6% of the variance was explained by the ACE-R only. No model emerged for BADL scores. Conclusions Cognitive deficits and apathy are key contributors to functional disability in bvFTD but factors underlying impairment in BADLs remain unclear. Treatments targeting reduction of disability need to address apathy and cognitive impairment to ensure greater efficacy, especially in regards to IADLs

    Genome-wide diversity and differentiation in New World populations of the human malaria parasite Plasmodium vivax.

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    BACKGROUND: The Americas were the last continent colonized by humans carrying malaria parasites. Plasmodium falciparum from the New World shows very little genetic diversity and greater linkage disequilibrium, compared with its African counterparts, and is clearly subdivided into local, highly divergent populations. However, limited available data have revealed extensive genetic diversity in American populations of another major human malaria parasite, P. vivax. METHODS: We used an improved sample preparation strategy and next-generation sequencing to characterize 9 high-quality P. vivax genome sequences from northwestern Brazil. These new data were compared with publicly available sequences from recently sampled clinical P. vivax isolates from Brazil (BRA, total n = 11 sequences), Peru (PER, n = 23), Colombia (COL, n = 31), and Mexico (MEX, n = 19). PRINCIPAL FINDINGS/CONCLUSIONS: We found that New World populations of P. vivax are as diverse (nucleotide diversity π between 5.2 × 10-4 and 6.2 × 10-4) as P. vivax populations from Southeast Asia, where malaria transmission is substantially more intense. They display several non-synonymous nucleotide substitutions (some of them previously undescribed) in genes known or suspected to be involved in antimalarial drug resistance, such as dhfr, dhps, mdr1, mrp1, and mrp-2, but not in the chloroquine resistance transporter ortholog (crt-o) gene. Moreover, P. vivax in the Americas is much less geographically substructured than local P. falciparum populations, with relatively little between-population genome-wide differentiation (pairwise FST values ranging between 0.025 and 0.092). Finally, P. vivax populations show a rapid decline in linkage disequilibrium with increasing distance between pairs of polymorphic sites, consistent with very frequent outcrossing. We hypothesize that the high diversity of present-day P. vivax lineages in the Americas originated from successive migratory waves and subsequent admixture between parasite lineages from geographically diverse sites. Further genome-wide analyses are required to test the demographic scenario suggested by our data

    Paper Spray Ionization Mass Spectrometry as a Potential Tool for Early Diagnosis of Cervical Cancer

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    Squamous intraepithelial lesion is an abnormal growth of epithelial cells on the surface of the cervix that may lead to cervical cancer. Analytical protocols for the determination of squamous intraepithelial lesions are in high demand, since cervical cancer is the fourth most diagnosed cancer among women in the world. Here, paper spray ionization mass spectrometry (PSI-MS) is used to distinguish between healthy (negative for intraepithelial lesion or malignancy) and diseased (high-grade squamous intraepithelial lesion) blood plasmas. A total of 86 blood samples of different women (49 healthy samples, 37 diseased samples) were collected, and the plasmas were prepared. Then, 10 μL of each plasma sample was deposited onto triangular papers for PSI-MS analysis. No additional step of sample preparation was necessary. The interval-successive projection algorithm linear discriminant analysis (iSPA-LDA) was applied to the PSI mass spectra, showing six ions (mostly phospholipids) that were predictive of healthy and diseased plasmas. Values of 77% accuracy, 86% sensitivity, 80% positive predictive value (PPV), and 75% negative predictive value (NPV) were achieved. This study provides evidence that PSI-MS may potentially be used as a fast and simple analytical technique for the early diagnosis of cervical cancer

    Measurement of the cross-section and charge asymmetry of WW bosons produced in proton-proton collisions at s=8\sqrt{s}=8 TeV with the ATLAS detector

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    This paper presents measurements of the W+μ+νW^+ \rightarrow \mu^+\nu and WμνW^- \rightarrow \mu^-\nu cross-sections and the associated charge asymmetry as a function of the absolute pseudorapidity of the decay muon. The data were collected in proton--proton collisions at a centre-of-mass energy of 8 TeV with the ATLAS experiment at the LHC and correspond to a total integrated luminosity of 20.2~\mbox{fb^{-1}}. The precision of the cross-section measurements varies between 0.8% to 1.5% as a function of the pseudorapidity, excluding the 1.9% uncertainty on the integrated luminosity. The charge asymmetry is measured with an uncertainty between 0.002 and 0.003. The results are compared with predictions based on next-to-next-to-leading-order calculations with various parton distribution functions and have the sensitivity to discriminate between them.Comment: 38 pages in total, author list starting page 22, 5 figures, 4 tables, submitted to EPJC. All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/STDM-2017-13

    Search for chargino-neutralino production with mass splittings near the electroweak scale in three-lepton final states in √s=13 TeV pp collisions with the ATLAS detector

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    A search for supersymmetry through the pair production of electroweakinos with mass splittings near the electroweak scale and decaying via on-shell W and Z bosons is presented for a three-lepton final state. The analyzed proton-proton collision data taken at a center-of-mass energy of √s=13  TeV were collected between 2015 and 2018 by the ATLAS experiment at the Large Hadron Collider, corresponding to an integrated luminosity of 139  fb−1. A search, emulating the recursive jigsaw reconstruction technique with easily reproducible laboratory-frame variables, is performed. The two excesses observed in the 2015–2016 data recursive jigsaw analysis in the low-mass three-lepton phase space are reproduced. Results with the full data set are in agreement with the Standard Model expectations. They are interpreted to set exclusion limits at the 95% confidence level on simplified models of chargino-neutralino pair production for masses up to 345 GeV

    Agricultura e biodiversidade nas ciências sociais brasileiras: alimentando a comunicação entre ciência e políticas públicas.

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    O presente artigo decorre de uma reflexão sustentada em dois pressupostos: a) que as ciências e, em particular, as sociais, podem contribuir para informar as tomadas de decisão e a formulação de políticas públicas visando a melhoria da vida das pessoas no planeta e b) que o papel da agricultura na conservação da biodiversidade é uma questão atual de extrema relevância e que merece ser aprofundada. A relação entre a agricultura e a biodiversidade tem sido objeto de questionamentos recentes na sociedade e no campo das políticas públicas. Contudo, se os estudos relacionados à biodiversidade e à agricultura, separadamente, têm observado um considerável crescimento no Brasil, poucos são os investimentos de pesquisa sobre a relação entre esses dois grandes temas. A partir dessas considerações, seguimos dois objetivos principais: 1) investigar como o papel da agricultura familiar na preservação da biodiversidade tem sido abordado pelas Ciências Sociais no Brasil, particularmente nos artigos publicados em periódicos brasileiros nos últimos 20 anos; 2) testar uma metodologia de revisão bibliográfica, criteriosa, que possa ser útil aos tomadores de decisão em políticas públicas e demais interessados
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