628 research outputs found
A rocky planet transiting a nearby low-mass star
M-dwarf stars -- hydrogen-burning stars that are smaller than 60 per cent of
the size of the Sun -- are the most common class of star in our Galaxy and
outnumber Sun-like stars by a ratio of 12:1. Recent results have shown that M
dwarfs host Earth-sized planets in great numbers: the average number of M-dwarf
planets that are between 0.5 to 1.5 times the size of Earth is at least 1.4 per
star. The nearest such planets known to transit their star are 39 parsecs away,
too distant for detailed follow-up observations to measure the planetary masses
or to study their atmospheres. Here we report observations of GJ 1132b, a
planet with a size of 1.2 Earth radii that is transiting a small star 12
parsecs away. Our Doppler mass measurement of GJ 1132b yields a density
consistent with an Earth-like bulk composition, similar to the compositions of
the six known exoplanets with masses less than six times that of the Earth and
precisely measured densities. Receiving 19 times more stellar radiation than
the Earth, the planet is too hot to be habitable but is cool enough to support
a substantial atmosphere, one that has probably been considerably depleted of
hydrogen. Because the host star is nearby and only 21 per cent the radius of
the Sun, existing and upcoming telescopes will be able to observe the
composition and dynamics of the planetary atmosphere.Comment: Published in Nature on 12 November 2015, available at
http://dx.doi.org/10.1038/nature15762. This is the authors' version of the
manuscrip
Germline TERT promoter mutations are rare in familial melanoma.
Germline CDKN2A mutations occur in 40 % of 3-or-more case melanoma families while mutations of CDK4, BAP1, and genes involved in telomere function (ACD, TERF2IP, POT1), have also been implicated in melanomagenesis. Mutation of the promoter of the telomerase reverse transcriptase (TERT) gene (c.-57 T>G variant) has been reported in one family. We tested for the TERT promoter variant in 675 multicase families wild-type for the known high penetrance familial melanoma genes, 1863 UK population-based melanoma cases and 529 controls. Germline lymphocyte telomere length was estimated in carriers. The c.-57 T>G TERT promoter variant was identified in one 7-case family with multiple primaries and early age of onset (earliest, 15 years) but not among population cases or controls. One family member had multiple primary melanomas, basal cell carcinomas and a bladder tumour. The blood leukocyte telomere length of a carrier was similar to wild-type cases. We provide evidence confirming that a rare promoter variant of TERT (c.-57 T>G) is associated with high penetrance, early onset melanoma and potentially other cancers, and explains <1 % of UK melanoma multicase families. The identification of POT1 and TERT germline mutations highlights the importance of telomere integrity in melanoma biology.The authors would like to thank the families for their willingness to participate; and Rajiv Kumar for the provision of mutation positive samples. The collection of samples in the UK population-ascertained sample set was funded by Cancer Research UK (awards C588/A19167 and C8216/A6129) and by the NIH (CA83115). The work of N.A.G. and R.v.D was supported by the Dutch Cancer Society (UL 2012-5489). D.J.A and C.D.R.E are supported by Cancer Research UK, ERC Combat Cancer and the Wellcome Trust. N.K.H is supported by a fellowship from the National Health and Medical Research Council of Australia. A.M.D. and K.A.P. were supported by CRUK grant (C8197/A16565) and The Isaac Newton Trust. K.M.B. is supported by the Intramural Research Program of the Division of Cancer Epidemiology and Genetics; National Cancer Institute; National Institutes of Health.This is the final version of the article. It first appeared from Springer via http://dx.doi.org/10.1007/s10689-015-9841-
Survival from cancer in young people: An overview of late effects focusing on reproductive health
This paper provides a summary of the areas of survival from childhood, teenage and young adult cancers and the significant late effects that can arise from treatment; with particular focus on the area of reproductive health and the impact on both fertility and pregnancy. To complete this review, Web of Science and MEDLINE were used. Search terms included: “"survival AND childhood OR teenage OR young adult cancer", "late effects", "childhood cancer", "teenage AND/OR young adult cancer", AND "fertility after cancer" OR "pregnancy AND cancer" OR "fertility preservation”. Additionally, the clinical expertise of the authors was drawn upon. Childhood cancer is a thankfully rare occurrence; however, the incidence is increasing. Survival rates remain high and this means that a growing population of childhood and young adult cancer survivors are reaching adulthood. For some of these adults, although cured of their cancer, they are now facing a future with lasting effects on their health from their treatments. These effects, commonly referred to as late effects, are defined as health problems related either directly to the underlying cancer or to its treatment and which occur months or years after treatment has finished. Reproductive health is an important consideration for these patients, and although many will be able to conceive naturally, some will exhibit impaired fertility after their treatments. This can include difficulties at all points along the path from conception to delivery of a live, healthy offspring. High‐quality, large‐population evidence is sparse in many areas relating to fertility risk from treatment and the maternal and fetal health of childhood cancer survivors. Yet given the potential for complications, the authors advocate consideration of fertility at the time of diagnosis and before potentially gonadotoxic treatment
Congenital and neonatal malaria in a rural Kenyan district hospital: an eight-year analysis.
BACKGROUND: Malaria remains a significant burden in sub-Saharan Africa. However, data on burden of congenital and neonatal malaria is scarce and contradictory, with some recent studies reporting a high burden. Using prospectively collected data on neonatal admissions to a rural district hospital in a region of stable malaria endemicity in Kenya, the prevalence of congenital and neonatal malaria was described. METHODS: From 1st January 2002 to 31st December 2009, admission and discharge information on all neonates admitted to Kilifi District Hospital was collected. At admission, blood was also drawn for routine investigations, which included a full blood count, blood culture and blood slide for malaria parasites. RESULTS: Of the 5,114 neonates admitted during the eight-year surveillance period, blood slide for malaria parasites was performed in 4,790 (93.7%). 18 (0.35%) neonates with Plasmodium falciparum malaria parasitaemia, of whom 11 were admitted within the first week of life and thus classified as congenital parasitaemia, were identified. 7/18 (39%) had fever. Parasite densities were low, ≤50 per μl in 14 cases. The presence of parasitaemia was associated with low haemoglobin (Hb) of <10 g/dl (χ² 10.9 P = 0.001). The case fatality rate of those with and without parasitaemia was similar. Plasmodium falciparum parasitaemia was identified as the cause of symptoms in four neonates. CONCLUSION: Congenital and neonatal malaria are rare in this malaria endemic region. Performing a blood slide for malaria parasites among sick neonates in malaria endemic regions is advisable. This study does not support routine treatment with anti-malarial drugs among admitted neonates with or without fever even in a malaria endemic region
Impacts of climate change on plant diseases – opinions and trends
There has been a remarkable scientific output on the topic of how climate change is likely to affect plant diseases in the coming decades. This review addresses the need for review of this burgeoning literature by summarizing opinions of previous reviews and trends in recent studies on the impacts of climate change on plant health. Sudden Oak Death is used as an introductory case study: Californian forests could become even more susceptible to this emerging plant disease, if spring precipitations will be accompanied by warmer temperatures, although climate shifts may also affect the current synchronicity between host cambium activity and pathogen colonization rate. A summary of observed and predicted climate changes, as well as of direct effects of climate change on pathosystems, is provided. Prediction and management of climate change effects on plant health are complicated by indirect effects and the interactions with global change drivers. Uncertainty in models of plant disease development under climate change calls for a diversity of management strategies, from more participatory approaches to interdisciplinary science. Involvement of stakeholders and scientists from outside plant pathology shows the importance of trade-offs, for example in the land-sharing vs. sparing debate. Further research is needed on climate change and plant health in mountain, boreal, Mediterranean and tropical regions, with multiple climate change factors and scenarios (including our responses to it, e.g. the assisted migration of plants), in relation to endophytes, viruses and mycorrhiza, using long-term and large-scale datasets and considering various plant disease control methods
Programa de intervención en representaciones de creatividad y motivación académica de adolescentes
Creativity and its promotion are widespread concerns in education. However, few efforts have been made to implement
intervention programs designed to promote creativity and other related aspects (e.g., academic motivation). The Future Problem Solving
Program International (FPSPI), aimed for training creativity representations and creative problem solving skills in young people, has
been one of the most implemented programs. This intervention’s materials and activities were adapted for Portuguese students, and
a longitudinal study was conducted. The program was implemented during four months, in weekly sessions, by thirteen teachers.
Teachers received previous training for the program and during the program’s implementation. Intervention participants included
77 Basic and Secondary Education students, and control participants included 78 equivalent students. Pretest-posttest measures of
academic motivation and creativity representations were collected. Results suggest a significant increase, in the intervention group,
in motivation and the appropriate representations of creativity. Practical implications and future research perspectives are presented.A criatividade e sua promoção geram grande preocupação em educação. Contudo, poucos esforços têm existido para
implementar programas destinados a sua promoção e de outros aspetos relacionados (e.g., motivação acadêmica). O Future Problem
Solving Program International (FPSPI), criado para melhorar as representações de criatividade e a resolução criativa de problemas
em jovens, tem sido um dos mais implementados. Os seus materiais e atividades foram adaptados para estudantes portugueses,
efetuando-se um estudo longitudinal. O programa foi implementado durante quatro meses, semanalmente, por treze professores, que
receberam formação antes e durante a implementação. O grupo experimental incluiu 77 estudantes do Ensino Básico e Secundário,
apresentando o grupo de controlo 78 estudantes com características equivalentes. Os dados sobre a motivação e criatividade foram
recolhidos num pré e pós-teste. Os resultados sugerem um aumento significativo na motivação e crenças apropriadas de criatividade
no grupo experimental. Implicações práticas e perspectivas para investigações futuras são apresentadas.La creatividad y su promoción generan gran preocupación en educación. Sin embargo, han sido llevados a cabo pocos
esfuerzos para implementar programas de promoción de la creatividad y otros aspectos (e.g., motivación académica). El Future
Problem Solving Program International (FPSPI), creado para mejorar las representaciones de creatividad y la solución creativa de
problemas en jóvenes, ha sido bastante implementado. Se adaptaron sus materiales y actividades para estudiantes portugueses, y
se desarrolló un estudio longitudinal. El programa se implementó semanalmente durante cuatro meses por trece profesores, que
recibieron formación antes y durante la implementación. El grupo experimental incluyó 77 estudiantes de Educación Primaria y
Secundaria y el grupo de control incluyó 78 estudiantes con características semejantes. Los datos de motivación y creatividad fueron
recogidos en un pre y post-test, sugiriendo un aumento significativo de motivación y creencias apropiadas sobre la creatividad en el
grupo experimental. Se presentan implicaciones prácticas y perspectivas para futuras investigaciones.Fundação para a Ciência e a Tecnologia (FCT) - SFRH/BPD/80825/201
Consumer trust and confidence in the compliance of Islamic banks
Islamic banks compete with traditional (non-Islamic) banks for customers. This article aims to provide insight into why some Muslims choose to bank with Islamic banks in Pakistan, while others do not. Specifically, it addresses the questions: to what extent are trust and confidence active influencers in the decision-making process, are they differentiated or are they one of the same? Also how does the Pakistani collective cultural context further complicate the application of these concepts? For the purposes of this article trust refers to people and their interpersonal or social relations whereas confidence concerns institutions such as banks. Drawing on interviews with Muslim consumers in Pakistan, this study provides further insight into consumer behaviour within financial services and specifically Islamic banking and contributes to our theoretical understanding of the concepts of trust and confidence
An Estimate of the Incidence of Prostate Cancer in Africa: A Systematic Review and Meta-Analysis
Prostate cancer (PCa) is rated the second most common cancer and sixth leading cause of
cancer deaths among men globally. Reports show that African men suffer disproportionately
from PCa compared to men from other parts of the world. It is still quite difficult to accurately
describe the burden of PCa in Africa due to poor cancer registration systems.We
systematically reviewed the literature on prostate cancer in Africa and provided a continentwide
incidence rate of PCa based on available data in the regio
Identification of a gene signature for discriminating metastatic from primary melanoma using a molecular interaction network approach
Understanding the biological factors that are characteristic of metastasis in melanoma remains a key approach to improving treatment. In this study, we seek to identify a gene signature of metastatic melanoma. We configured a new network-based computational pipeline, combined with a machine learning method, to mine publicly available transcriptomic data from melanoma patient samples. Our method is unbiased and scans a genome-wide protein-protein interaction network using a novel formulation for network scoring. Using this, we identify the most influential, differentially expressed nodes in metastatic as compared to primary melanoma. We evaluated the shortlisted genes by a machine learning method to rank them by their discriminatory capacities. From this, we identified a panel of 6 genes, ALDH1A1, HSP90AB1, KIT, KRT16, SPRR3 and TMEM45B whose expression values discriminated metastatic from primary melanoma (87% classification accuracy). In an independent transcriptomic data set derived from 703 primary melanomas, we showed that all six genes were significant in predicting melanoma specific survival (MSS) in a univariate analysis, which was also consistent with AJCC staging. Further, 3 of these genes, HSP90AB1, SPRR3 and KRT16 remained significant predictors of MSS in a joint analysis (HR = 2.3, P = 0.03) although, HSP90AB1 (HR = 1.9, P = 2 × 10−4) alone remained predictive after adjusting for clinical predictors
Determination of sin2 θeff w using jet charge measurements in hadronic Z decays
The electroweak mixing angle is determined with high precision from measurements of the mean difference between forward and backward hemisphere charges in hadronic decays of the Z. A data sample of 2.5 million hadronic Z decays recorded over the period 1990 to 1994 in the ALEPH detector at LEP is used. The mean charge separation between event hemispheres containing the original quark and antiquark is measured for bb̄ and cc̄ events in subsamples selected by their long lifetimes or using fast D*'s. The corresponding average charge separation for light quarks is measured in an inclusive sample from the anticorrelation between charges of opposite hemispheres and agrees with predictions of hadronisation models with a precision of 2%. It is shown that differences between light quark charge separations and the measured average can be determined using hadronisation models, with systematic uncertainties constrained by measurements of inclusive production of kaons, protons and A's. The separations are used to measure the electroweak mixing angle precisely as sin2 θeff w = 0.2322 ± 0.0008(exp. stat.) ±0.0007(exp. syst.) ± 0.0008(sep.). The first two errors are due to purely experimental sources whereas the third stems from uncertainties in the quark charge separations
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