435 research outputs found
Wolf 1130: A Nearby Triple System Containing a Cool, Ultramassive White Dwarf
Following the discovery of the T8 subdwarf WISEJ200520.38+542433.9 (Wolf
1130C), with common proper motion to a binary (Wolf 1130AB) consisting of an M
subdwarf and a white dwarf, we set out to learn more about the old binary in
the system. We find that the A and B components of Wolf 1130 are tidally
locked, which is revealed by the coherence of more than a year of V band
photometry phase folded to the derived orbital period of 0.4967 days. Forty new
high-resolution, near-infrared spectra obtained with the Immersion Grating
Infrared Spectrometer (IGRINS) provide radial velocities and a projected
rotational velocity (v sin i) of 14.7 +/- 0.7 km/s for the M subdwarf. In
tandem with a Gaia parallax-derived radius and verified tidal-locking, we
calculate an inclination of i=29 +/- 2 degrees. From the single-lined orbital
solution and the inclination we derive an absolute mass for the unseen primary
(1.24+0.19-0.15 Msun). Its non-detection between 0.2 and 2.5 microns implies
that it is an old (>3.7 Gyr) and cool (Teff<7000K) ONe white dwarf. This is the
first ultramassive white dwarf within 25pc. The evolution of Wolf 1130AB into a
cataclysmic variable is inevitable, making it a potential Type Ia supernova
progenitor. The formation of a triple system with a primary mass >100 times the
tertiary mass and the survival of the system through the common-envelope phase,
where ~80% of the system mass was lost, is remarkable. Our analysis of Wolf
1130 allows us to infer its formation and evolutionary history, which has
unique implications for understanding low-mass star and brown dwarf formation
around intermediate mass stars.Comment: 37 pages, 9 Figures, 5 Table
Exploring perceptions and approaches of registered managers regarding clinical safety in care homes in the UK.
Context: Around 400,000 people currently live in care homes with increasing complexity of care needs and co-morbidities. Despite this, there is a paucity of research that asks questions about how the care and clinical safety of this vulnerable population are managed.
Objective: The aim of this research was to understand how registered care home managers approach clinical safety and what they feel helps or hinders them in this.
Methods: The research took a Heideggerian, interpretative phenomenological approach, embracing the closeness of the researcher to the participants and the subject matter to uncover rich and detailed findings. Five registered managers of care homes owned by one provider participated in semi-structured interviews between March and May 2020. Three of the interviews took place in the managers’ care homes and, due to coronavirus restrictions, two were undertaken via video conferencing software.
Findings: Thematic analysis of the data generated unexpected findings demonstrating the significant impact on clinical safety in care homes caused not by the managers themselves, but by external forces including regulation, shortcomings in the structure of the health and social care system in the UK and complex relationships between care homes and other agencies.
Limitations: The strengths (e.g. in-depth data) and limitations (e.g. only including care homes in one area) of this phenomenological qualitative study are discussed.
Implications: The findings led to recommendations that further research and reviews should be undertaken urgently to understand these factors in more detail. This would provide valuable guidance to inform system-wide reform to ensure better clinical safety for care home residents
Proteomic analysis of follicular fluid in carriers and non-carriers of the Trio allele for high ovulation rate in cattle
This study was conducted to characterise differences in follicular fluid proteins between carriers and non-carriers of a bovine allele for high ovulation rate. A total of four non-carrier and five carrier females were used in an initial study with four and six additional non-carriers and carriers respectively used in a validation study. Emergence of the follicular wave was synchronised and the ovaries containing the dominant follicle(s) were extracted by ovariectomy for follicular fluid collection. A hexapeptide ligand library was used to overcome the masking effect of high-abundance proteins and to increase detection of low-abundance proteins in tandem mass spectrometry. After correcting for multiple comparisons, only two proteins, glia-derived nexin precursor (SERPINE2) and inhibin β B chain precursor (INHBB), were significantly differentially expressed (false-discovery rate <0.05). In a replicate study of analogous design differential expression was confirmed (P<0.05). Joint analysis of results from the two studies indicated that three additional proteins were consistently differentially expressed between genotypes. For three of these five, previous studies have indicated that expression is increased by transforming growth factor-β-bone morphogenetic protein signalling; their reduction in follicular fluid from carrier animals is consistent with the ~9-fold overexpression of SMAD family member 6 (SMAD6) in carriers that is inhibitory to this pathway
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The influence of negative and affective symptoms on anhedonia self-report in schizophrenia.
BACKGROUND: Anhedonia, a symptom prevalent in schizophrenia patients, is thought to arise either within negative symptomatology or from secondary sources, such as depression. The common co-occurrence of these diseases complicates the assessment of anhedonia in schizophrenia. METHOD: In a sample of 40 outpatients with chronic schizophrenia, we explored both the validity of the Snaith-Hamilton Pleasure Scale (SHAPS) self-report for anhedonia assessment and those factors influenced its scoring. We assessed negative symptoms using the Brief Negative Symptom Scale (BNSS), depression symptoms using the Calgary Depression Scale for Schizophrenia (CDSS) and cognitive impairment using the Brief Assessment of Cognition in Schizophrenia (BACS), before exploring associations between these scales. RESULTS: The SHAPS was validated for use in schizophrenia. SHAPS scores were not associated with negative symptoms or cognitive impairment, but were linked to a single Depression symptom: Hopelessness (r = 0.52, p < 0.001). CONCLUSIONS: SHAPS scores, therefore, appear to only reflect anticipatory anhedonia arising from the affective domain. We advocate the development of multi-faceted self-report measures to more holistically assess anhedonia in schizophrenia.M.H is funded by a Wellcome Trust Principal Research Fellowship and by the NIHR BRC at Oxford.
E.F.E and the research database were supported by intramural funding from CPFT and the UK National Institute of Health Research (NIHR) Cambridge Biomedical Research Centre (BRC)
Trio a novel bovine high-fecundity allele: II. Hormonal profile and follicular dynamics underlying the high ovulation rate
The newly discovered Trio high-fecundity allele produces multiple ovulations in cattle. This study evaluated (1) size and growth rates of follicles in Trio carriers during a synchronized follicular wave, induced by follicle aspiration; (2) follicle-stimulating hormone (FSH) patterns associated with the follicular wave; (3) size of corpora lutea (CL) and circulating progesterone; and (4) intrafollicular estradiol concentrations prior to normal deviation. Trio carriers had mean dominant follicles that were significantly smaller in diameter and volume than noncarriers. Onset of diameter deviation occurred at ∼3 days after the last follicle aspiration in both genotypes despite Trio carriers having much smaller individual follicles. Follicles of Trio carriers grew at a slower rate than noncarrier follicles (∼65% in mm/day or ∼30% in mm3/day) resulting in much smaller individual dominant follicles (∼25% volume). However, total dominant follicle volume, calculated as the sum of all dominant follicles in each animal, was similar in carriers and noncarriers of Trio throughout the entire follicular wave. Circulating FSH was greater in Trio carriers during the 24 h encompassing deviation. Trio carriers had significantly more ovulations than noncarriers, and individual CL volume was smaller, although total luteal tissue volume and circulating P4 were not different. Thus, increased ovulation rate in Trio carriers relates to smaller individual follicles (one-third the volume) near the time of deviation due to slower follicle growth rate, although time of deviation is similar, with increased circulating FSH near deviation leading to selection of multiple dominant follicles in Trio carriers with similar total follicle volume
Abnormal glycemic homeostasis at the onset of serious mental illnesses: A common pathway
Objective: Patients with serious mental illnesses exhibit a reduced lifespan compared with the general population, a finding that can not solely rely on high suicide risk, low access to medical care and unhealthy lifestyle. The main causes of death are medical related pathologies such as type 2 diabetes mellitus and cardiovascular disease; however pharmacological treatment might play a role. Material and methods: We compared a two hour glucose load in naïve patients at the onset of a serious mental illness (N = 102) (84 patients with a first episode of schizophrenia and related disorders, 6 with a first episode of bipolar I disorder and 12 with a first episode of major depression disorder) with another psychiatric diagnose, adjustment disorder (N = 17) and matched controls (N = 98). Results: Young patients with serious mental illness showed an increased two hour glucose load compared with adjustment disorder and the control group. Mean two hour glucose values [±standard deviation] were: for schizophrenia and related disorders 106.51 mg/dL [±32.0], for bipolar disorder 118.33 mg/dL [±34.3], for major depressive disorder 107.42 mg/dL [±34.5], for adjustment disorder 79.06 mg/dL[±24.4] and for the control group 82.11 mg/dL [±23.3] (p < 0.001). Conclusions: Our results reflect an abnormal metabolic pathway at the onset of the disease before any pharmacological treatment or other confounding factors might have taken place. Our results suggest a similar glycemic pathway in serious mental illnesses and the subsequent need of primary and secondary prevention strategies
A Chandra study of the large-scale shock and cool filaments in Hydra A: Evidence for substantial gas dredge-up by the central outburst
We present the results of a Chandra study of the Hydra A galaxy cluster,
where a powerful AGN outburst created a large-scale cocoon shock. We
investigated possible azimuthal variations in shock strength and shape, finding
indications for a weak shock with a Mach number in the range ~1.2-1.3. We
measured the temperature change across the shock front. However, the detection
of a temperature rise in the regions immediately inside of the front is
complicated by the underlying temperature profile of the cluster atmosphere. We
measured the global temperature profile of the cluster up to 700 kpc, which
represents the farthest measurement obtained with Chandra for this cluster. A
"plateau" in the temperature profile in the range ~70-150 kpc indicates the
presence of cool gas, which is likely the result of uplift of material by the
AGN outburst. After masking the cool filaments visible in the hardness ratio
map, the plateau disappears and the temperature profile recovers a typical
shape with a peak around 190 kpc, just inside the shock front. However, it is
unlikely that such a temperature feature is produced by the shock as it is
consistent with the general shape of the temperature profiles observed for
relaxed galaxy clusters. We studied the spectral properties of the cool
filaments finding evidence that ~10^11 M_sun of low-entropy material has been
dredged up by the rising lobes from the central 30 kpc to the observed current
position of 75-150 kpc. The energy required to lift the cool gas is >~2.2 x
10^60 erg, which is comparable to the work required to inflate the cavities and
is ~25% of the total energy of the large-scale shock. Our results show that the
AGN feedback in Hydra A is acting not only by directly heating the gas, but
also by removing a substantial amount of potential fuel for the SMBH.Comment: 11 pages, 9 figures, accepted for publication in ApJ (version with
full resolution figures available at
http://www.bo.astro.it/~myriam/files/papers/gitti-hydra.pdf
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Association of birth weight and the development of antipsychotic induced adiposity in individuals with treatment resistant schizophrenia.
Though weight gain is a common side effect of antipsychotic treatment, there are no useful predictors of which patients are likely to be affected and to what degree. It has been shown that exposure to adverse conditions during intra-uterine life confers a vulnerability to the development of later life metabolic complications and low birth weight for gestational age has been shown to be a robust marker of such prenatal adversity. We hypothesised that patients with schizophrenia with a lower birth weight will have increased vulnerability to the weight inducing effects of antipsychotic treatment. The relationship between birth weight and total and central adiposity, measured as body mass index (BMI) and waist-to-hip ratio (WHR) respectively, was examined in three groups: drug naïve first episode of psychosis (FEP) patients (n=41), treatment resistant schizophrenia (TRS) patients (n=42) and matched healthy volunteers (n=72). All analyses were controlled for age, gender and duration of treatment exposure. We found that a lower birth weight was associated with higher BMI and WHR only in TRS patients but not in FEP or controls, suggesting that prenatal adversity, as indicated by the surrogate marker of a lower birth weight, confers an increased vulnerability to clozapine induced weight gain.This is the author accepted manuscript. The final version is available from Elsevier via http://dx.doi.org/10.1016/j.euroneuro.2016.03.00
A new ornithischian dinosaur and the terrestrial vertebrate fauna from a bone bed in the Wealden of Ardingly, West Sussex
The Wealden Supergroup of south-east England has long been of interest to palaeontologists because of its diverse flora and fauna. The Supergroup is Early Cretaceous in age, occupying the time period immediately after the enigmatic end-Jurassic extinction. Wealden faunas therefore have the potential to be informative about the tempo and mode of post-extinction recovery, but due to lack of exposure in this densely populated part of southern England, are difficult to sample. In the summer of 2012, a number of ex situ fossiliferous blocks of sandstone, siltstone and limestone were discovered from building excavations at Ardingly College, near Haywards Heath in West Sussex. The sedimentology of the blocks indicates that they are from the Valanginian Hastings Group, and that Ardingly College is underlain by the Grinstead Clay Formation, rather than the Ardingly Sandstone Member. The blocks contain a diverse invertebrate fauna and flora, as well as vertebrate remains, which are found in a distinct sandstone horizon that probably represents the Top Lower Tunbridge Wells pebble bed. A tooth from an ornithschian dinosaur cannot be referred to any of the ornithischian taxa known from the Wealden Supergroup, and therefore represents a new taxon. Teeth of the crocodilian Theriosuchus extend the known range of this taxon in the Wealden, while teeth of an ornithocheird pterosaur confirm the presence of these animals in the skies above the Wealden sub-basins. Fusainized plant remains and the wing-case of a cupedid beatle indicate that wildfire was a ubiquitous feature of the Weald Sub-basin during the Valanginian
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