551 research outputs found

    Good vibrations: A novel method for sexing turtles

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    The ability to accurately determine the sex of individuals is important for research and conservation efforts. While most species of turtle exhibit secondary sexual dimorphisms that can be used to reliably infer sex, there are some species that are very difficult to sex, and even within many dimorphic species, it is not uncommon to encounter individuals that appear to exhibit both male and female secondary sex characteristics. Therefore, we tested the novel method of using a vibrator to sex turtles by stimulating male turtles to evert their penises. We tested this method on males of four species (three families) with known sexual dimorphisms: spiny softshell turtles (Apalone spinifera; n = 14), western chicken turtles (Deirochelys reticularia miaria; n = 17), Mississippi mud turtles (Kinosternon subrubrum hippocrepis; n = 10), and common musk turtles (Sternotherus odoratus; n = 9). The method accurately sexed 100% of A. spinifera, 64.7% of D. r. miaria, 80.0% of K. s. hippocrepis, and 55.6% of S. odoratus. Despite the low success rates in some species, there are situations in which this method will be useful for researchers working with species that are difficult to sex using external morphological characteristics

    Good vibrations: a novel method for sexing turtles

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    The ability to accurately determine the sex of individuals is important for research and conservation efforts. While most species of turtle exhibit secondary sexual dimorphisms that can be used to reliably infer sex, there are some species that are very difficult to sex, and even within many dimorphic species, it is not uncommon to encounter individuals that appear to exhibit both male and female secondary sex characteristics. Therefore, we tested the novel method of using a vibrator to sex turtles by stimulating male turtles to evert their penises. We tested this method on males of four species (three families) with known sexual dimorphisms: spiny softshell turtles (Apalone spinifera; n = 14), western chicken turtles (Deirochelys reticularia miaria; n = 17), Mississippi mud turtles (Kinosternon subrubrum hippocrepis; n = 10), and common musk turtles (Sternotherus odoratus; n = 9). The method accurately sexed 100% of A. spinifera, 64.7% of D. r. miaria, 80.0% of K. s. hippocrepis, and 55.6% of S.odoratus. Despite the low success rates in some species, there are situations in which this method will be useful for researchers working with species that are difficult to sex using external morphological characteristics

    Egg and clutch sizes of western chicken turtles (Deirochelys reticularia miaria)

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    Chicken turtles (Deirochelys reticularia) are generally characterized as having atypical reproductive characteristics relative to other sympatric emydids. However, the comparatively understudied western chicken turtle (D. r. miaria) has been shown to exhibit some reproductive characteristics that differ from the other subspecies. Therefore, we examined clutch and egg sizes from six D. r. miaria (13 clutches) in Oklahoma and compared the results to values that have been reported for the other two subspecies. Females nested up to three times per year, with clutches ranging from 8-13 eggs per clutch (mean = 10.9). The eggs were 19.4-25.3 mm wide (mean = 22.2 mm). These values are greater than the means reported for the other subspecies, but the differences were not statistically significant

    Good vibrations: a novel method for sexing turtles

    Get PDF
    The ability to accurately determine the sex of individuals is important for research and conservation efforts. While most species of turtle exhibit secondary sexual dimorphisms that can be used to reliably infer sex, there are some species that are very difficult to sex, and even within many dimorphic species, it is not uncommon to encounter individuals that appear to exhibit both male and female secondary sex characteristics. Therefore, we tested the novel method of using a vibrator to sex turtles by stimulating male turtles to evert their penises. We tested this method on males of four species (three families) with known sexual dimorphisms: spiny softshell turtles (Apalone spinifera; n = 14), western chicken turtles (Deirochelys reticularia miaria; n = 17), Mississippi mud turtles (Kinosternon subrubrum hippocrepis; n = 10), and common musk turtles (Sternotherus odoratus; n = 9). The method accurately sexed 100% of A. spinifera, 64.7% of D. r. miaria, 80.0% of K. s. hippocrepis, and 55.6% of S. odoratus. Despite the low success rates in some species, there are situations in which this method will be useful for researchers working with species that are difficult to sex using external morphological characteristics

    Frontal and superior temporal auditory processing abnormalities in schizophrenia

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    AbstractBackgroundAlthough magnetoencephalography (MEG) studies show superior temporal gyrus (STG) auditory processing abnormalities in schizophrenia at 50 and 100ms, EEG and corticography studies suggest involvement of additional brain areas (e.g., frontal areas) during this interval. Study goals were to identify 30 to 130ms auditory encoding processes in schizophrenia (SZ) and healthy controls (HC) and group differences throughout the cortex.MethodsThe standard paired-click task was administered to 19 SZ and 21 HC subjects during MEG recording. Vector-based Spatial–temporal Analysis using L1-minimum-norm (VESTAL) provided 4D maps of activity from 30 to 130ms. Within-group t-tests compared post-stimulus 50ms and 100ms activity to baseline. Between-group t-tests examined 50 and 100ms group differences.ResultsBilateral 50 and 100ms STG activity was observed in both groups. HC had stronger bilateral 50 and 100ms STG activity than SZ. In addition to the STG group difference, non-STG activity was also observed in both groups. For example, whereas HC had stronger left and right inferior frontal gyrus activity than SZ, SZ had stronger right superior frontal gyrus and left supramarginal gyrus activity than HC.ConclusionsLess STG activity was observed in SZ than HC, indicating encoding problems in SZ. Yet auditory encoding abnormalities are not specific to STG, as group differences were observed in frontal and SMG areas. Thus, present findings indicate that individuals with SZ show abnormalities in multiple nodes of a concurrently activated auditory network

    Validation of Kepler's Multiple Planet Candidates. III: Light Curve Analysis & Announcement of Hundreds of New Multi-planet Systems

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    The Kepler mission has discovered over 2500 exoplanet candidates in the first two years of spacecraft data, with approximately 40% of them in candidate multi-planet systems. The high rate of multiplicity combined with the low rate of identified false-positives indicates that the multiplanet systems contain very few false-positive signals due to other systems not gravitationally bound to the target star (Lissauer, J. J., et al., 2012, ApJ 750, 131). False positives in the multi- planet systems are identified and removed, leaving behind a residual population of candidate multi-planet transiting systems expected to have a false-positive rate less than 1%. We present a sample of 340 planetary systems that contain 851 planets that are validated to substantially better than the 99% confidence level; the vast majority of these have not been previously verified as planets. We expect ~2 unidentified false-positives making our sample of planet very reliable. We present fundamental planetary properties of our sample based on a comprehensive analysis of Kepler light curves and ground-based spectroscopy and high-resolution imaging. Since we do not require spectroscopy or high-resolution imaging for validation, some of our derived parameters for a planetary system may be systematically incorrect due to dilution from light due to additional stars in the photometric aperture. None the less, our result nearly doubles the number of verified exoplanets.Comment: 138 pages, 8 Figures, 5 Tables. Accepted for publications in the Astrophysical Journa

    Critical research gaps and translational priorities for the successful prevention and treatment of breast cancer

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    INTRODUCTION Breast cancer remains a significant scientific, clinical and societal challenge. This gap analysis has reviewed and critically assessed enduring issues and new challenges emerging from recent research, and proposes strategies for translating solutions into practice. METHODS More than 100 internationally recognised specialist breast cancer scientists, clinicians and healthcare professionals collaborated to address nine thematic areas: genetics, epigenetics and epidemiology; molecular pathology and cell biology; hormonal influences and endocrine therapy; imaging, detection and screening; current/novel therapies and biomarkers; drug resistance; metastasis, angiogenesis, circulating tumour cells, cancer 'stem' cells; risk and prevention; living with and managing breast cancer and its treatment. The groups developed summary papers through an iterative process which, following further appraisal from experts and patients, were melded into this summary account. RESULTS The 10 major gaps identified were: (1) understanding the functions and contextual interactions of genetic and epigenetic changes in normal breast development and during malignant transformation; (2) how to implement sustainable lifestyle changes (diet, exercise and weight) and chemopreventive strategies; (3) the need for tailored screening approaches including clinically actionable tests; (4) enhancing knowledge of molecular drivers behind breast cancer subtypes, progression and metastasis; (5) understanding the molecular mechanisms of tumour heterogeneity, dormancy, de novo or acquired resistance and how to target key nodes in these dynamic processes; (6) developing validated markers for chemosensitivity and radiosensitivity; (7) understanding the optimal duration, sequencing and rational combinations of treatment for improved personalised therapy; (8) validating multimodality imaging biomarkers for minimally invasive diagnosis and monitoring of responses in primary and metastatic disease; (9) developing interventions and support to improve the survivorship experience; (10) a continuing need for clinical material for translational research derived from normal breast, blood, primary, relapsed, metastatic and drug-resistant cancers with expert bioinformatics support to maximise its utility. The proposed infrastructural enablers include enhanced resources to support clinically relevant in vitro and in vivo tumour models; improved access to appropriate, fully annotated clinical samples; extended biomarker discovery, validation and standardisation; and facilitated cross-discipline working. CONCLUSIONS With resources to conduct further high-quality targeted research focusing on the gaps identified, increased knowledge translating into improved clinical care should be achievable within five years

    Planetary Candidates Observed by Kepler V: Planet Sample from Q1-Q12 (36 Months)

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    The Kepler mission discovered 2842 exoplanet candidates with 2 years of data. We provide updates to the Kepler planet candidate sample based upon 3 years (Q1-Q12) of data. Through a series of tests to exclude false-positives, primarily caused by eclipsing binary stars and instrumental systematics, 855 additional planetary candidates have been discovered, bringing the total number known to 3697. We provide revised transit parameters and accompanying posterior distributions based on a Markov Chain Monte Carlo algorithm for the cumulative catalogue of Kepler Objects of Interest. There are now 130 candidates in the cumulative catalogue that receive less than twice the flux the Earth receives and more than 1100 have a radius less than 1.5 Rearth. There are now a dozen candidates meeting both criteria, roughly doubling the number of candidate Earth analogs. A majority of planetary candidates have a high probability of being bonafide planets, however, there are populations of likely false-positives. We discuss and suggest additional cuts that can be easily applied to the catalogue to produce a set of planetary candidates with good fidelity. The full catalogue is publicly available at the NASA Exoplanet Archive.Comment: Accepted for publication, ApJ

    Evaluation of the current knowledge limitations in breast cancer research: a gap analysis

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    BACKGROUND A gap analysis was conducted to determine which areas of breast cancer research, if targeted by researchers and funding bodies, could produce the greatest impact on patients. METHODS Fifty-six Breast Cancer Campaign grant holders and prominent UK breast cancer researchers participated in a gap analysis of current breast cancer research. Before, during and following the meeting, groups in seven key research areas participated in cycles of presentation, literature review and discussion. Summary papers were prepared by each group and collated into this position paper highlighting the research gaps, with recommendations for action. RESULTS Gaps were identified in all seven themes. General barriers to progress were lack of financial and practical resources, and poor collaboration between disciplines. Critical gaps in each theme included: (1) genetics (knowledge of genetic changes, their effects and interactions); (2) initiation of breast cancer (how developmental signalling pathways cause ductal elongation and branching at the cellular level and influence stem cell dynamics, and how their disruption initiates tumour formation); (3) progression of breast cancer (deciphering the intracellular and extracellular regulators of early progression, tumour growth, angiogenesis and metastasis); (4) therapies and targets (understanding who develops advanced disease); (5) disease markers (incorporating intelligent trial design into all studies to ensure new treatments are tested in patient groups stratified using biomarkers); (6) prevention (strategies to prevent oestrogen-receptor negative tumours and the long-term effects of chemoprevention for oestrogen-receptor positive tumours); (7) psychosocial aspects of cancer (the use of appropriate psychosocial interventions, and the personal impact of all stages of the disease among patients from a range of ethnic and demographic backgrounds). CONCLUSION Through recommendations to address these gaps with future research, the long-term benefits to patients will include: better estimation of risk in families with breast cancer and strategies to reduce risk; better prediction of drug response and patient prognosis; improved tailoring of treatments to patient subgroups and development of new therapeutic approaches; earlier initiation of treatment; more effective use of resources for screening populations; and an enhanced experience for people with or at risk of breast cancer and their families. The challenge to funding bodies and researchers in all disciplines is to focus on these gaps and to drive advances in knowledge into improvements in patient care
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