429 research outputs found

    Community structure informs species geographic distributions

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    This is the author accepted manuscript. The final version is available from Public Library of Science via the DOI in this recordUnderstanding what determines species’ geographic distributions is crucial for assessing global change threats to biodiversity. Measuring limits on distributions is usually, and necessarily, done with data at large geographic extents and coarse spatial resolution. However, survival of individuals is determined by processes that happen at small spatial assembly processes occurring at small scales, and are often available for relatively extensive areas, so could be useful for explaining species distributions. We demonstrate that Bayesian Network Inference (BNI) can overcome several challenges to including community structure into studies of species distributions, despite having been little used to date. We hypothesized that the relative abundance of coexisting species can improve predictions of species distributions. In 1570 assemblages of 68 Mediterranean woody plant species we used BNI to incorporate community structure into Species Distribution Models (SDMs), alongside environmental information. Information on species associations improved SDM predictions of community structure and species distributions moderately, though for some habitat specialists the deviance explained increased by up to 15%. We demonstrate that most species associations (95%) were positive and occurred between species with ecologically similar traits. This suggests that SDM improvement could be because species co-occurrences are a proxy for local ecological processes. Our study shows that Bayesian Networks, when interpreted carefully, can be used to include local conditions into measurements of species’ large-scale distributions, and this information can improve the predictions of species distributionsThis work was funded by FCT Project “QuerCom” (EXPL/AAG-GLO/2488/2013) and the ERA-Net BiodivERsA project “EC21C” (BIODIVERSA/0003/2011). A.M.N. was supported by a Bolsa de Investigacao de Pos-doutoramento (BI_Pos-Doc_UEvora_Catedra Rui Nabeiro_EXPL_AAG-GLO_2488_2013) and postdoctoral fellowships from the Ministry of Economy and Competitivity (FPDI-2013-16266 and IJCI‐2015‐23498). MGM acknowledges support by a Marie Curie Intra-European Fellowship within the 7th European Community Framework Programme (FORECOMM). J. Vicente is supported by POPH/FSE funds and by National Funds through FCT - Foundation for Science and Technology under the Portuguese Science Foundation (FCT) through Post-doctoral grant SFRH/BPD/84044/2012. AE has a postdoctoral contract funded by the project CN-17-022 (Principado de Asturias, Spain). We are grateful to OneGeology for providing the geological data

    Magneto-transport study of intra- and intergrain transitions in the magnetic superconductors RuSr2GdCu2O8 and RuSr2(Gd1.5Ce0.5)Cu2O10

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    A characterization of the magnetic superconductors RuSr2GdCu2O8 [Ru-(1212)] and RuSr2(Gd1.5Ce0.5)Cu2O10 [Ru-(1222)] through resistance measurements as a function of temperature and magnetic field is presented. Two peaks in the derivative of the resistive curves are identified as intra- and intergrain superconducting transitions. Strong intragrain granularity effects are observed, and explained by considering the antiphase boundaries between structural domains of coherently rotated RuO6 octahedra as intragrain Josephson-junctions. A different field dependence of the intragrain transition temperature in these compounds was found. For Ru-(1212) it remains unchanged up to 0.1 T, decreasing for higher fields. In Ru-(1222) it smoothly diminishes with the increase in field even for a value as low as 100 Oe. These results are interpreted as a consequence of a spin-flop transition of the Ru moments. The large separation between the RuO2 layers in Ru-(1222) promotes a weak interlayer coupling, leading the magnetic transition to occur at lower fields. The suppression rate of the intragrain transition temperature is about five times higher for Ru-(1222), a result we relate to an enhancement of the 2D character of the vortex structure. A distinctive difference with conventional cuprates is the sharp increase in amplitude of the intergrain peak in both systems, as the field is raised, which is ascribed to percolation through a fraction of high quality intergrain junctions.Comment: Submitted for Physical Review

    Probing the fuzzy sphere regularisation in simulations of the 3d \lambda \phi^4 model

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    We regularise the 3d \lambda \phi^4 model by discretising the Euclidean time and representing the spatial part on a fuzzy sphere. The latter involves a truncated expansion of the field in spherical harmonics. This yields a numerically tractable formulation, which constitutes an unconventional alternative to the lattice. In contrast to the 2d version, the radius R plays an independent r\^{o}le. We explore the phase diagram in terms of R and the cutoff, as well as the parameters m^2 and \lambda. Thus we identify the phases of disorder, uniform order and non-uniform order. We compare the result to the phase diagrams of the 3d model on a non-commutative torus, and of the 2d model on a fuzzy sphere. Our data at strong coupling reproduce accurately the behaviour of a matrix chain, which corresponds to the c=1-model in string theory. This observation enables a conjecture about the thermodynamic limit.Comment: 31 pages, 15 figure

    Multiple metachronous malignancies, one patient with three primary malignancies: a case report

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    We present a 61 year old Para 4 woman who presented with stage II Infiltrating lobular carcinoma of the breast after modified radical mastectomy. She was treated with Tamoxifen for seven years. She was diagnosed with multiple myeloma during year seven post mastectomy because of wrist pain. She was treated with melphalan, prednisone and allopurinol which she tolerated well and the pain in the wrist improved. Tamoxifen was also stopped. Ten months later she presented with vaginal bleeding and was diagnosed with a poorly differentiated endometrial adenocarcinoma at hysteroscopic suction curettage and had an abdominal hysterectomy. Two years later the patient succumbed to metastatic endometrial cancer

    Future possibilities in the prevention of breast cancer: Breast cancer prevention trials

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    The available results from breast cancer chemoprevention trials are reviewed. Four trials using tamoxifen have been performed, of which three have reported efficacy results. A fifth trial using raloxifene has also been reported. The largest tamoxifen trial showed approximately 50% reduction in breast cancer incidence in the short term, but the two smaller trials did not find any reduction. Greater agreement exists for side effects; incidences of thromboembolic disease and endometrial cancers are raised approximately threefold when tamoxifen is used for 5 years. The possible reasons for the discrepancy in breast cancer reduction are explored. A review of trial parameters does not clearly explain this difference, and a meta-analysis indicates that all results are compatible with a 40% reduction in short-term incidence. Several important questions remain regarding the clinical implications of this result, including the effect on mortality, the appropriate risk groups for chemoprevention and the long-term effects on incidence. Continued follow up of these trials is crucial for resolving these issues

    Estrogen receptor degradation: a CUE for endocrine resistance?

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    Despite the undoubted success of adjuvant endocrine therapies that target the estrogen receptor pathway, not all women with estrogen receptor-positive breast cancer respond to these therapies, and many who initially respond will subsequently relapse. Deregulation of various aspects of estrogen receptor signaling has been highlighted as a mechanism of resistance and as a basis for alternative therapeutic approaches. However, a recent publication refocuses attention on the estrogen receptor itself by showing that the ubiquitin-binding CUE domain-containing protein 2 is a regulator of estrogen receptor protein degradation and a marker of endocrine resistance in breast cancer

    The Impact of Major Events on the Lives of Family Caregivers of Children with Disabilities

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    Copyright 1996 Families International, Inc.The authors examine the family caregiving experience among families with children with severe emotional disabilities from a perspective that recognizes the importance of the family's views and feelings. This viewpoint anticipates the occurrence of both positive and negative experiences and seeks to illuminate the caregiving process from the perspective of outcomes achieved. Family caregivers of 164 children with serious emotional disorders were asked to identify major pleasant and stressful events that had occurred in the past 12 months. The most frequently described pleasant events related to children's behavior, school activities, and interactions with professionals and friends. Frequently described problem areas included children's behavior, professionals/services, and difficulty with school. The impact of these pleasant and stressful events was examined with respect to caregivers' perceived well-being: (I) overall stress, (2) the ability to fulfill responsibilities, and (3) pleasure experienced in various life domains. Implications of the study findings for supporting family caregivers in their roles are discussed

    Options for early breast cancer follow-up in primary and secondary care : a systematic review

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    Background Both incidence of breast cancer and survival have increased in recent years and there is a need to review follow up strategies. This study aims to assess the evidence for benefits of follow-up in different settings for women who have had treatment for early breast cancer. Method A systematic review to identify key criteria for follow up and then address research questions. Key criteria were: 1) Risk of second breast cancer over time - incidence compared to general population. 2) Incidence and method of detection of local recurrence and second ipsi and contra-lateral breast cancer. 3) Level 1–4 evidence of the benefits of hospital or alternative setting follow-up for survival and well-being. Data sources to identify criteria were MEDLINE, EMBASE, AMED, CINAHL, PSYCHINFO, ZETOC, Health Management Information Consortium, Science Direct. For the systematic review to address research questions searches were performed using MEDLINE (2011). Studies included were population studies using cancer registry data for incidence of new cancers, cohort studies with long term follow up for recurrence and detection of new primaries and RCTs not restricted to special populations for trials of alternative follow up and lifestyle interventions. Results Women who have had breast cancer have an increased risk of a second primary breast cancer for at least 20 years compared to the general population. Mammographically detected local recurrences or those detected by women themselves gave better survival than those detected by clinical examination. Follow up in alternative settings to the specialist clinic is acceptable to women but trials are underpowered for survival. Conclusions Long term support, surveillance mammography and fast access to medical treatment at point of need may be better than hospital based surveillance limited to five years but further large, randomised controlled trials are needed

    Cumulative survival in early-onset unilateral and bilateral breast cancer: an analysis of 1907 Taiwanese women

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    As the epidemiological pattern of breast cancer in modernising Asian countries differs greatly from that in Western countries, it is worthwhile to investigate the long-term prognoses of unilateral and bilateral breast cancer in these nations. A retrospective cohort study composed of 1907 Taiwanese women was conducted to follow 1863 unilateral and 44 bilateral cases of breast cancer. Time-dependent Cox regression was used to assess the risk of breast cancer death by considering the time course of unilateral and bilateral tumour development. The 15-year survival rates were 68.37, 62.63, and 26.42% for unilateral, synchronous bilateral, and metachronous bilateral breast cancer, respectively. Differences among types were most apparent after 5 years of follow-up. After adjusting for significant prognostic factors, the risk of death for overall bilateral breast cancer was 2.50-fold greater (95% CI, 1.43–4.37) compared to unilateral breast cancer. The corresponding figures were 1.12-fold (95% CI, 0.42–3.02) and 6.11-fold (95% CI, 3.14–11.89) for synchronous and metachronous bilateral breast cancer, respectively. Taiwanese women, who are frequently diagnosed with breast cancer before 50 years of age, showed poorer survival for metachronous bilateral than for synchronous bilateral or unilateral breast cancer. Survival was markedly poorer compared to recent data from Sweden
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