1,513 research outputs found

    Enhanced electrical conductivities of N-doped carbon nanotubes by controlled heat treatment

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    The thermal stability of nitrogen (N) functionalities on the sidewalls of N-doped multi-walled carbon nanotubes was investigated at temperatures ranging between 1000 degrees C and 2000 degrees C. The structural stability of the doped tubes was then correlated with the electrical conductivity both at the bulk and at the individual tube levels. When as-grown tubes were thermally treated at 1000 degrees C, we observed a very significant decrease in the electrical resistance of the individual nanotubes, from 54 k Omega to 0.5 k Omega, which is attributed to a low N doping level (e.g. 0.78 at% N). We noted that pyridine-type N was first decomposed whereas the substitutional N was stable up to 1500 degrees C. For nanotubes heat treated to 1800 degrees C and 2000 degrees C, the tubes exhibited an improved degree of crystallinity which was confirmed by both the low R value (I(D)/I(G)) in the Raman spectra and the presence of straight graphitic planes observed in TEM images. However, N atoms were not detected in these tubes and caused an increase in their electrical resistivity and resistance. These partially annealed doped tubes with enhanced electrical conductivities could be used in the fabrication of robust and electrically conducting composites, and these results could be extrapolated to N-doped graphene and other nanocarbons.ArticleNANOSCALE. 3(10):4359-4364 (2011)journal articl

    Enoturismo e segurança nas tendências do período pós-pandêmico: análise do Vale dos Vinhedos

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    O artigo visa contribuir com o enoturismo como alternativa de um segmento turístico seguro e uma tendência em meio ao período pós pandêmico no Vale dos Vinhedos, região localizada no Rio Grande do Sul. Para a justificativa, pode-se apontar o crescente interesse e consumo de vinhos durante a pandemia da COVID-19, além de novas tendências no turismo como destinos com mais atrativos ao ar livre após o período de isolamento social,  novas preocupações com saúde e preferências por atividades visando gestão de riscos. O método de abordagem utilizado foi o indutivo. Com isso, verificou-se a relação entre as medidas de prevenção adotadas durante a pandemia da Covid-19 e a necessidade de informar aos visitantes sobre elas, mostrando que as vinícolas analisadas preocupam-se com a segurança dos seus consumidores, visto que é um fator importante para a visitação. Com o enoturismo sendo uma prática realizada majoritariamente ao livre, o segmento supre a demanda de visitantes que manterão as preocupações com a segurança, gestão de riscos, saúde e qualidade de vida decidir o destino para a viagem no período pós pandêmico

    A genomic approach for the identification of population management units for the dolphinfish (Coryphaena hippurus) in the eastern Pacific

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    In the Tropical Eastern Pacific dolphinfish (TEP) Corypahena hippurus is part of commercial, recreational, and artisanal fisheries and is also caught incidentally by the tuna purse-seine and longline fisheries. Defining the existence of differenced populations in exploited species for being considered independent management units is crucial for conservation plans. However, there is a great uncertainty about the species population genetic structure across the TEP. To investigate it and to identify possible management units for conservation purposes this study was carried out, based on two SNPs datasets of 3867 and 3220 SNPs for young of the year (YOY) and adult individuals, respectively, obtained through NGS protocols. Sampling covered the species’ range distribution in the Tropical Eastern Pacific and was structured into YOY and adult individuals in order to discard the effects of migrating individuals into sampled locations. Our results revealed slight but significant differences among locations occupying the latitudinal limits of the species distribution at transitional areas between tropical and subtropical waters. These areas are characterized by strong seasonal variations in sea surface temperature and limit the prevalence of populations in these extremes. Genetic differences also seem to be related to spatial separation of locations as the northernmost (Los Cabos) and southernmost (Peru) locations including a set of oceanic samples, showed the highest levels of genetic differentiation. Whereas were detected barriers to gene flow among spatially separated locations for YOY individuals probably related to site fidelity, clear limitations to gene flow between Mexico and Central America locations were observed probably related to oceanic circulation in the area. Design management strategies in countries where the dolphinfish is explored is of primary interest to preserve genetic resources. It is necessary to define the existence of genetic differences of populations for species that are highly dependent on environmental factors limiting its distributional range as is the case of the dolphinfish

    Glossário de responsabilidade social

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    Este Glossário de Responsabilidade Social é um produto da RSO PT, pelo que as referências ao mesmo deverão ser efetuadas mencionando o nome do documento e os seus autores: Rede RSO PT, GT ISO 26000, Glossário de Responsabilidade Social, (2013)Este Glossário de Responsabilidade Social foi desenvolvido no âmbito da Rede RSO PT, no Grupo de Trabalho da ISO 26 000 (GT ISO 26000). A missão do GT ISO 26000 consiste em promover e aprofundar o conhecimento sobre a norma NP ISO 26000 Linhas de Orientação para a Responsabilidade Social. O Glossário de Responsabilidade Social seguiu a estrutura da norma de referência NP ISO 26000 Linhas de orientação para a responsabilidade social, pelo que os termos se encontram associados aos sete temas da norma.APEE; APSHSTDC; BSD; Câmara Municipal da Amadora; Câmara Municipal de Loures; Câmara Municipal de Oliveira de Azeméis; CIG; CITE; Coordenada Social; CTCV; Edit Value; GEBALIS; IAPMEI; Instituto de Informática, IP; Instituto Português da Qualidade; Montepio; Process Advice; State of The Art; Universidade Abert

    Pan-Cancer Analysis of lncRNA Regulation Supports Their Targeting of Cancer Genes in Each Tumor Context

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    Long noncoding RNAs (lncRNAs) are commonly dys-regulated in tumors, but only a handful are known toplay pathophysiological roles in cancer. We inferredlncRNAs that dysregulate cancer pathways, onco-genes, and tumor suppressors (cancer genes) bymodeling their effects on the activity of transcriptionfactors, RNA-binding proteins, and microRNAs in5,185 TCGA tumors and 1,019 ENCODE assays.Our predictions included hundreds of candidateonco- and tumor-suppressor lncRNAs (cancerlncRNAs) whose somatic alterations account for thedysregulation of dozens of cancer genes and path-ways in each of 14 tumor contexts. To demonstrateproof of concept, we showed that perturbations tar-geting OIP5-AS1 (an inferred tumor suppressor) andTUG1 and WT1-AS (inferred onco-lncRNAs) dysre-gulated cancer genes and altered proliferation ofbreast and gynecologic cancer cells. Our analysis in-dicates that, although most lncRNAs are dysregu-lated in a tumor-specific manner, some, includingOIP5-AS1, TUG1, NEAT1, MEG3, and TSIX, synergis-tically dysregulate cancer pathways in multiple tumorcontexts

    Pan-cancer Alterations of the MYC Oncogene and Its Proximal Network across the Cancer Genome Atlas

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    Although theMYConcogene has been implicated incancer, a systematic assessment of alterations ofMYC, related transcription factors, and co-regulatoryproteins, forming the proximal MYC network (PMN),across human cancers is lacking. Using computa-tional approaches, we define genomic and proteo-mic features associated with MYC and the PMNacross the 33 cancers of The Cancer Genome Atlas.Pan-cancer, 28% of all samples had at least one ofthe MYC paralogs amplified. In contrast, the MYCantagonists MGA and MNT were the most frequentlymutated or deleted members, proposing a roleas tumor suppressors.MYCalterations were mutu-ally exclusive withPIK3CA,PTEN,APC,orBRAFalterations, suggesting that MYC is a distinct onco-genic driver. Expression analysis revealed MYC-associated pathways in tumor subtypes, such asimmune response and growth factor signaling; chro-matin, translation, and DNA replication/repair wereconserved pan-cancer. This analysis reveals insightsinto MYC biology and is a reference for biomarkersand therapeutics for cancers with alterations ofMYC or the PMN

    Genomic, Pathway Network, and Immunologic Features Distinguishing Squamous Carcinomas

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    This integrated, multiplatform PanCancer Atlas study co-mapped and identified distinguishing molecular features of squamous cell carcinomas (SCCs) from five sites associated with smokin

    Spatial Organization and Molecular Correlation of Tumor-Infiltrating Lymphocytes Using Deep Learning on Pathology Images

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    Beyond sample curation and basic pathologic characterization, the digitized H&E-stained images of TCGA samples remain underutilized. To highlight this resource, we present mappings of tumorinfiltrating lymphocytes (TILs) based on H&E images from 13 TCGA tumor types. These TIL maps are derived through computational staining using a convolutional neural network trained to classify patches of images. Affinity propagation revealed local spatial structure in TIL patterns and correlation with overall survival. TIL map structural patterns were grouped using standard histopathological parameters. These patterns are enriched in particular T cell subpopulations derived from molecular measures. TIL densities and spatial structure were differentially enriched among tumor types, immune subtypes, and tumor molecular subtypes, implying that spatial infiltrate state could reflect particular tumor cell aberration states. Obtaining spatial lymphocytic patterns linked to the rich genomic characterization of TCGA samples demonstrates one use for the TCGA image archives with insights into the tumor-immune microenvironment
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