272 research outputs found

    ALMA reveals the aftermath of a white dwarf–brown dwarf merger in CK Vulpeculae

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    We present Atacama Large Millimeter–Submillimeter Array (ALMA) observations of CK Vulpeculae which is identified with “Nova Vulpeculae 1670”. They trace obscuring dust in the inner regions of the associated nebulosity. The dust forms two cocoons, each extending ∼5″ north and south of the presumed location of the central star. Brighter emission is in a more compact east–west structure (2″ × 1″) where the cocoons intersect. We detect line emission in NH2CHO, CN, four organic molecules and C17O. CN lines trace bubbles within the dusty cocoons; CH3OH a north–south S–shaped jet; and other molecules a central cloud with a structure aligned with the innermost dust structure. The major axis of the overall dust and gas bubble structure has a projected inclination of ∼24° with respect to a 71″ extended “hourglass” nebulosity, previously seen in Hα. Three cocoon limbs align with dark lanes in the inner regions of the same Hα images. The central 2″ × 1″ dust is resolved into a structure consistent with a warped dusty disc. The velocity structure of the jets indicates an origin at the centre of this disc and precession with an unknown period. Deceleration regions at both the northern and southern tips of the jets are roughly coincident with additional diffuse dust emission over regions approximately 2″ across. These structures are consistent with a bipolar outflow expanding into surrounding high density material. We suggest that a white dwarf and brown dwarf merged between 1670 and 1672, with the observed structures and extraordinary isotopic abundances generated as a result

    Muddy waters: critiquing the historical criminology method in the investigation of the Smiley Face murders theory

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    As an emerging trans-disciplinary field, the operational use of historical criminology is a largely under-studied area. Examination of the use of archival research in studying cases connected to Gannon and Gilbertson’s Smiley Face murders theory indicates that there is clear potential for historical criminology to be used to revisit closed or cold investigations to determine if the official findings of the case are consistent with the evidence. In the case of the Smiley Face murders theory, taking a historical criminology approach has failed to prove the hypothesis of researchers; nevertheless, use of historical research methods has had some success in forcing a re-evaluation of several cases, and should be considered an important tool in future investigations of this nature

    Different Transport Pathways of Individual Precursor Proteins in Mitochondria

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    Transport of mitochondrial precursor proteins into mitochondria of Neurospora crassa was studied in a cellfree reconstituted system. Precursors were synthesized in a reticulocyte lysate programmed with Neurospora mRNA and transported into isolated mitochondria in the absence of protein synthesis. Uptake of the following precursors was investigated: apocytochrome c, ADP/ATP carrier and subunit 9 of the oligomycin-sensitive ATPase. Addition of high concentrations of unlabelled chemically prepared apocytochrome c (1–10 μM) inhibited the appearance in the mitochondrial of labelled cytochrome c synthesized in vitro because the unlabelled protein dilutes the labelled one and because the translocation system has a limited capacity [apparent V is 1–3 pmol × min−1× (mg mitochondrial protein)−1]. Concentrations of added apocytochrome c exceeding the concentrations of precursor proteins synthesized in vitro by a factor of about 104 did not inhibit the transfer of ADP/ATP carrier or ATPase subunit 9 into mitochondria. Carbonylcyanide m-chlorophenylhydrazone, an uncoupler of oxidative phosphorylation, inhibited transfer in vitro of ADP/ATP carrier and of ATPase subunit 9, but not of cytochrome c. These findings suggest that cytochrome c and the other two proteins have different import pathways into mitochondria. It can be inferred from the data presented that different 'receptors' on the mitochondrial surface mediate the specific recognition of precursor proteins by mitochondria as a first step in the transport process

    Slow dynamics and aging in a non-randomly frustrated spin system

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    A simple, non-disordered spin model has been studied in an effort to understand the origin of the precipitous slowing down of dynamics observed in supercooled liquids approaching the glass transition. A combination of Monte Carlo simulations and exact calculations indicates that this model exhibits an entropy vanishing transition accompanied by a rapid divergence of time scales. Measurements of various correlation functions show that the system displays a hierarchy of time scales associated with different degrees of freedom. Extended structures, arising from the frustration in the system, are identified as the source of the slow dynamics. In the simulations, the system falls out of equilibrium at a temperature TgT_{g} higher than the entropy-vanishing transition temperature and the dynamics below TgT_{g} exhibits aging as distinct from coarsening. The cooling rate dependence of the energy is also consistent with the usual glass formation scenario.Comment: 41 pages, 16 figures. Bibliography file is correcte

    Cold-induced changes in gene expression in brown adipose tissue, white adipose tissue and liver

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    Cold exposure imposes a metabolic challenge to mammals that is met by a coordinated response in different tissues to prevent hypothermia. This study reports a transcriptomic analysis in brown adipose tissue (BAT), white adipose (WAT) and liver of mice in response to 24 h cold exposure at 8°C. Expression of 1895 genes were significantly (P<0.05) up- or down-regulated more than two fold by cold exposure in all tissues but only 5 of these genes were shared by all three tissues, and only 19, 14 and 134 genes were common between WAT and BAT, WAT and liver, and BAT and liver, respectively. We confirmed using qRT-PCR, the increased expression of a number of characteristic BAT genes during cold exposure. In both BAT and the liver, the most common direction of change in gene expression was suppression (496 genes in BAT and 590 genes in liver). Gene ontology analysis revealed for the first time significant (P<0.05) down regulation in response to cold, of genes involved in oxidoreductase activity, lipid metabolic processes and protease inhibitor activity, in both BAT and liver, but not WAT. The results reveal an unexpected importance of down regulation of cytochrome P450 gene expression and apolipoprotein, in both BAT and liver, but not WAT, in response to cold exposure. Pathway analysis suggests a model in which down regulation of the nuclear transcription factors HNF4α and PPARα in both BAT and liver may orchestrate the down regulation of genes involved in lipoprotein and steroid metabolism as well as Phase I enzymes belonging to the cytochrome P450 group in response to cold stress in mice. We propose that the response to cold stress involves decreased gene expression in a range of cellular processes in order to maximise pathways involved in heat production

    A Clinician\u27s Guide to Next Generation Imaging in Patients With Advanced Prostate Cancer (RADAR III).

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    PURPOSE: The advanced prostate cancer therapeutic landscape has changed dramatically in the last several years, resulting in improved overall survival of patients with castration naïve and castration resistant disease. The evolution and development of novel next generation imaging techniques will affect diagnostic and therapeutic decision making. Clinicians must navigate when and which next generation imaging techniques to use and how to adjust treatment strategies based on the results, often in the absence of correlative therapeutic data. Therefore, guidance is needed based on best available information and current clinical experience. MATERIALS AND METHODS: The RADAR (Radiographic Assessments for Detection of Advanced Recurrence) III Group convened to offer guidance on the use of next generation imaging to stage prostate cancer based on available data and clinical experience. The group also discussed the potential impact of next generation imaging on treatment options based on earlier detection of disease. RESULTS: The group unanimously agreed that progression to metastatic disease is a seminal event for patient treatment. Next generation imaging techniques are able to detect previously undetectable metastases, which could redefine the phases of prostate cancer progression. Thus, earlier systemic or locally directed treatment may positively alter patient outcomes. CONCLUSIONS: The RADAR III Group recommends next generation imaging techniques in select patients in whom disease progression is suspected based on laboratory (biomarker) values, comorbidities and symptoms. Currently 18F-fluciclovine and 68Ga prostate specific membrane antigen positron emission tomography/computerized tomography are the next generation imaging agents with a favorable combination of availability, specificity and sensitivity. There is ongoing research of additional next generation imaging technologies, which may offer improved diagnostic accuracy and therapeutic options. As next generation imaging techniques evolve and presumably result in improved global accessibility, clinician ability to detect micrometastases may be enhanced for decision making and patient outcomes

    Depth of reading vocabulary in hearing and hearing-impaired children

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    The main point of our study was to examine the vocabulary knowledge of pupils in grades 3–6, and in particular the relative reading vocabulary disadvantage of hearing-impaired pupils. The achievements of 394 pupils with normal hearing and 106 pupils with a hearing impairment were examined on two vocabulary assessment tasks: a lexical decision task and a use decision task. The target words in both tasks represent the vocabulary children should have at the end of primary school. The results showed that most hearing pupils reached this norm, whereas most hearing-impaired pupils did not. In addition, results showed that hearing-impaired pupils not only knew fewer words, but that they also knew them less well. This lack of deeper knowledge remained even when matching hearing and hearing-impaired children on minimal word knowledge. Additionally, comparison of the two tasks demonstrated the efficacy of the lexical decision task as a measure of lexical semantic knowledge

    Study protocol of a multicentre randomised controlled trial of self-help cognitive behaviour therapy for working women with menopausal symptoms (MENOS@Work)

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    Background Hot flushes and night sweats (HFNS) – the main symptoms of the menopause transition – can reduce quality of life and are particularly difficult to manage at work. A cognitive behaviour therapy (CBT) intervention has been developed specifically for HFNS that is theoretically based and shown to reduce significantly the impact of HFNS in several randomised controlled trials (RCTs). Self-help CBT has been found to be as effective as group CBT for these symptoms, but these interventions are not widely available in the workplace. This paper describes the protocol of an RCT aiming to assess the efficacy of CBT for menopausal symptoms implemented in the workplace, with a nested qualitative study to examine acceptability and feasibility. Methods/Design One hundred menopausal working women, aged 45–60 years, experiencing bothersome HFNS for two months will be recruited from several (2–10) large organisations into a multicentre randomised controlled trial. Women will be randomly assigned to either treatment (a self-help CBT intervention lasting 4 weeks) or to a no treatment-wait control condition (NTWC), following a screening interview, consent, and completion of a baseline questionnaire. All participants will complete follow-up questionnaires at 6 weeks and 20 weeks post-randomisation. The primary outcome is the rating of HFNS; secondary measures include HFNS frequency, mood, quality of life, attitudes to menopause, HFNS beliefs and behaviours, work absence and presenteeism, job satisfaction, job stress, job performance, disclosure to managers and turnover intention. Adherence, acceptability and feasibility will be assessed at 20 weeks post-randomisation in questionnaires and qualitative interviews. Upon trial completion, the control group will also be offered the intervention. Discussion This is the first randomised controlled trial of a self-management intervention tailored for working women who have troublesome menopausal symptoms
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