21 research outputs found

    Pan-cancer analysis of whole genomes

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    Cancer is driven by genetic change, and the advent of massively parallel sequencing has enabled systematic documentation of this variation at the whole-genome scale(1-3). Here we report the integrative analysis of 2,658 whole-cancer genomes and their matching normal tissues across 38 tumour types from the Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium of the International Cancer Genome Consortium (ICGC) and The Cancer Genome Atlas (TCGA). We describe the generation of the PCAWG resource, facilitated by international data sharing using compute clouds. On average, cancer genomes contained 4-5 driver mutations when combining coding and non-coding genomic elements; however, in around 5% of cases no drivers were identified, suggesting that cancer driver discovery is not yet complete. Chromothripsis, in which many clustered structural variants arise in a single catastrophic event, is frequently an early event in tumour evolution; in acral melanoma, for example, these events precede most somatic point mutations and affect several cancer-associated genes simultaneously. Cancers with abnormal telomere maintenance often originate from tissues with low replicative activity and show several mechanisms of preventing telomere attrition to critical levels. Common and rare germline variants affect patterns of somatic mutation, including point mutations, structural variants and somatic retrotransposition. A collection of papers from the PCAWG Consortium describes non-coding mutations that drive cancer beyond those in the TERT promoter(4); identifies new signatures of mutational processes that cause base substitutions, small insertions and deletions and structural variation(5,6); analyses timings and patterns of tumour evolution(7); describes the diverse transcriptional consequences of somatic mutation on splicing, expression levels, fusion genes and promoter activity(8,9); and evaluates a range of more-specialized features of cancer genomes(8,10-18).Peer reviewe

    COVID-19 pandemic-related anxiety, stress, and depression among teachers: A systematic review and meta-analysis.

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    BACKGROUND: As millions of teachers have been forced to rely upon remote teaching due to the closure of schools during the COVID-19 pandemic. It is particularly important to understand the extent to which teacher's psychological wellbeing has been affected by this global health crisis. OBJECTIVE: The aim of this comprehensive systematic review and meta-analysis was twofold: 1) ascertain the prevalence of stress, anxiety, depression among teachers during the COVID-19 outbreak; 2) identify the associated factors of these psychological wellbeing domains of the teachers. METHODS: Academic Search Premier, Eric, PsycInfo, Scopus, and Web of Science were searched for articles published from December 2019 and July 2021, using search terms including "COVID-19" "anxiety" "depression" "stress", and "teachers". RESULTS: This study included 54 studies synthesising data from 256,896 teachers across 22 countries. The meta-analysis showed higher prevalence of stress (62.6%, 95% Confidence Interval [CI]: 46.1-76.6), compared to anxiety (36.3%, 95% CI: 28.5-44.9) and depression (59.9%, 95% CI: 43.4-74.4) among teachers. Teachers' experiences of these psychological issues were associated with various socio-demographic and institutional factors, including gender, nature of online teaching, job satisfaction, teaching experience, and the volume of workload. Additionally, several protective factors, such as regular exercises and provision of technical support for online teaching, reduced teachers' negative psychological experiences. CONCLUSION: There is a need for authorities to formulate educational policies to improve teachers' wellbeing at the time of global crisis. Special attention should be paid to assist female teachers in overcoming physical and mental stressors

    Modelos de servicios bibliotecarios: el acceso a la información

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    El acceso a los servicios bibliotecarios se ha visto modificado y adaptado con el paso del tiempo. El modelo cerrado, instaurado por la realeza, nobleza y los dueños de las bibliotecas, que perduró hasta el siglo XV se transformó en un modelo abierto al permitir la entrada a los ciudadanos a los fondos. Hasta finales del siglo XX, los usuarios acudían a los centros para consultar fondos y satisfacer sus necesidades documentales. Desde finales del siglo XX es posible acceder a la información a través de Internet y gracias a las asociaciones y consorcios de las bibliotecas la oferta documental ha incrementado, teniendo en cuenta connotaciones como la propiedad física de los documentos frente a la propiedad virtual de los mismos. El sistema bibliotecario en combinación con las tecnologías de la información y la comunicación ha modificado el modelo de servicios existente hasta la fecha
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