97 research outputs found
High spatial resolution optical imaging of the multiple T Tauri system LkH{\alpha} 262/LkH{\alpha} 263
We report high spatial resolution i' band imaging of the multiple T Tauri
system LkH 262/LkH 263 obtained during the first commissioning
period of the Adaptive Optics Lucky Imager (AOLI) at the 4.2 m William Herschel
Telescope, using its Lucky Imaging mode. AOLI images have provided photometry
for each of the two components LkH 263 A and B (0.41 arcsec separation)
and marginal evidence for an unresolved binary or a disc in LkH 262.
The AOLI data combined with previously available and newly obtained optical and
infrared imaging show that the three components of LkH 263 are
co-moving, that there is orbital motion in the AB pair, and, remarkably, that
LkH 262-263 is a common proper motion system with less than 1 mas/yr
relative motion. We argue that this is a likely five-component gravitationally
bounded system. According to BT-settl models the mass of each of the five
components is close to 0.4 M and the age is in the range 1-2 Myr. The
presence of discs in some of the components offers an interesting opportunity
to investigate the formation and evolution of discs in the early stages of
multiple very low-mass systems. In particular, we provide tentative evidence
that the disc in 263C could be coplanar with the orbit of 263AB.Comment: 11 pages, 7 figures, Accepted 2016 May
Nephrotoxicity in Patients With or Without Cystic Fibrosis Treated With Polymyxin B Compared to Colistin
Nephrotoxicity is the primary adverse effect of the polymyxins. The relative rates of toxicity of polymyxin B and colistin have not been fully elucidated, especially in patients with cystic fibrosis (CF). A retrospective cohort study of adults treated with polymyxin B or colistin for at least 48 h was conducted. The primary endpoint was the incidence of kidney injury assessed by RIFLE (i.e., risk, injury, failure, loss, end-stage renal disease) criteria. Risk factors for kidney injury were evaluated using multivariate Cox regression. A total of 414 patients were evaluated, 220 of whom had CF. In patients without CF, there was no difference in kidney injury with polymyxin B and colistin (42.9% versus 50.3%, P = 0.46). Loop diuretic exposure was a risk factor for kidney injury (adjusted hazard ratio [aHR], 1.82; 95% confidence interval [CI], 1.16 to 2.83) in this population. In patients with CF, polymyxin B and colistin were associated with similar rates of kidney injury (34.5% versus 29.8%, P = 0.77). Diabetes (aHR, 2.68; 95% CI, 1.01 to 7.11), loop diuretics (aHR, 3.02; 95% CI, 1.36 to 6.73), and progressive care unit admission (aHR, 8.21; 95% CI, 2.55 to 26.46) were risk factors for kidney injury, while higher baseline serum creatinine levels (per 1 mg/dl) were protective (aHR, 0.08; 95% CI, 0.01 to 0.48). Total unadjusted kidney injury in polymyxin-treated patients was less frequent in those who had CF (30.5% versus 48.5%, P \u3c 0.001). Polymyxin B and colistin are associated with a high incidence of kidney injury; cystic fibrosis may be protective against polymyxin nephrotoxicity, but further investigation is needed to confirm this conjecture
The political process of constructing a sustainable London Olympics sports development legacy
This study attempts to develop a research agenda for understanding the process of constructing a sustainable Olympic sports development legacy. The research uses a social constructivist perspective to examine the link between the 2012 London Olympic Games and sustainable sports development. The first part of the paper provides justification for the study of sport policy processes using a constructivist lens. This is followed by a section which critically unpacks sustainable sports development drawing on Mosse’s (1998) ideas of process-oriented research and Searle’s conceptualisation of the construction of social reality. Searle’s (1995) concepts of the assignment of function, collective intentionality, collective rules, and human capacity to cope with the environment are considered in relation to the events and discourses emerging from the legacy vision(s) associated with the 2012 London Olympic Games. The paper concludes by proposing a framework for engaging in process oriented research and highlights key elements, research questions, and methodological issues. The proposed constructivist approach can be used to inform policy, practice, and research on sustainable Olympic sports development legacy
Pharmacodynamic effect of bempedoic acid and statin combinations: predictions from a dose–response model
Aims Many patients are unable to achieve guideline-recommended LDL cholesterol (LDL-C) targets, despite taking maximally tolerated lipid-lowering therapy. Bempedoic acid, a competitive inhibitor of ATP citrate lyase, significantly lowers LDL-C with or without background statin therapy in diverse populations. Because pharmacodynamic interaction between statins and bempedoic acid is complex, a dose-response model was developed to predict LDL-C pharmacodynamics following administration of statins combined with bempedoic acid. Methods And Results Bempedoic acid and statin dosing and LDL-C data were pooled from 14 phase 1-3 clinical studies. Dose-response models were developed for bempedoic acid monotherapy and bempedoic acid-statin combinations using previously published statin parameters. Simulations were performed using these models to predict change in LDL-C levels following treatment with bempedoic acid combined with clinically relevant doses of atorvastatin, rosuvastatin, simvastatin, and pravastatin. Dose-response models predicted that combining bempedoic acid with the lowest statin dose of commonly used statins would achieve a similar degree of LDL-C lowering as quadrupling that statin dose" for example, the predicted LDL-C lowering was 54% with atorvastatin 80 mg compared with 54% with atorvastatin 20 mg + bempedoic acid 180 mg, and 42% with simvastatin 40 mg compared with 46% with simvastatin 10 mg + bempedoic acid 180 mg. Conclusion These findings suggest bempedoic acid combined with lower statin doses offers similar LDL-C lowering compared with statin monotherapy at higher doses, potentially sparing patients requiring additional lipid-lowering therapies from the adverse events associated with higher statin doses
Final Design and On-Sky Testing of the iLocater SX Acquisition Camera: Broadband Single-Mode Fiber Coupling
Enabling efficient injection of light into single-mode fibers (SMFs) is a key
requirement in realizing diffraction-limited astronomical spectroscopy on
ground-based telescopes. SMF-fed spectrographs, facilitated by the use of
adaptive optics (AO), offer distinct advantages over comparable seeing-limited
designs, including higher spectral resolution within a compact and stable
instrument volume, and a telescope independent spectrograph design. iLocater is
an extremely precise radial velocity (EPRV) spectrograph being built for the
Large Binocular Telescope (LBT). We have designed and built the front-end fiber
injection system, or acquisition camera, for the SX (left) primary mirror of
the LBT. The instrument was installed in 2019 and underwent on-sky
commissioning and performance assessment. In this paper, we present the
instrument requirements, acquisition camera design, as well as results from
first-light measurements. Broadband single-mode fiber coupling in excess of 35%
(absolute) in the near-infrared (0.97-1.31{\mu}m) was achieved across a range
of target magnitudes, spectral types, and observing conditions. Successful
demonstration of on-sky performance represents both a major milestone in the
development of iLocater and in making efficient ground-based SMF-fed
astronomical instruments a reality.Comment: 18 pages, 17 figures. Accepted for publication in MNRA
The C3a Anaphylatoxin Receptor Is a Key Mediator of Insulin Resistance and Functions by Modulating Adipose Tissue Macrophage Infiltration and Activation
Introduction to “Binary Binds”: Deconstructing Sex and Gender Dichotomies in Archaeological Practice
YesGender archaeology has made significant strides toward deconstructing the hegemony of binary categorizations. Challenging dichotomies such as man/woman, sex/gender, and biology/culture, approaches informed by poststructuralist, feminist, and queer theories have moved beyond essentialist and universalist identity constructs to more nuanced configurations. Despite the theoretical emphasis on context, multiplicity, and fluidity, binary starting points continue to streamline the spectrum of variability that is recognized, often reproducing normative assumptions in the evidence. The contributors to this special issue confront how sex, gender, and sexuality categories condition analytical visibility, aiming to develop approaches that respond to the complexity of theory in archaeological practice. The papers push the ontological and epistemological boundaries of bodies, personhood, and archaeological possibility, challenging a priori assumptions that contain how sex, gender, and sexuality categories are constituted and related to each other. Foregrounding intersectional approaches that engage with ambiguity, variability, and difference, this special issue seeks to “de-contain” categories, assumptions, and practices from “binding” our analytical gaze toward only certain kinds of persons and knowledges, in interpretations of the past and practices in the present
Reappraisal of linezolid dosing in renal impairment to improve safety
Linezolid is administered as a fixed dose to all patients despite evidence of increased exposure and myelosuppression in renal impairment. The objectives of these studies were to assess the risk of thrombocytopenia with standard-dose linezolid in renal impairment and to identify an alternate dosing strategy. In study 1, data from adult patients receiving linezolid for 10 days were retrospectively reviewed to determine the frequency of thrombocytopenia in patients with and without renal impairment. Time-to-event analyses were performed using Cox proportional-hazards models. In study 2, population pharmacokinetic modeling was employed to build covariatestructured models using an independent data set of linezolid concentrations obtained during routine therapeutic drug monitoring (TDM). Monte Carlo simulations were performed to identify linezolid dosing regimens that maximized attainment of therapeutic trough concentrations (2 to 8 mg/liter) across various renal-function groups. Toxicity analysis (study 1) included 341 patients, 133 (39.0%) with renal impairment. Thrombocytopenia occurred more frequently among patients with renal impairment (42.9% versus 16.8%; P<0.001), and renal impairment was independently associated with this toxicity in multivariable analysis (adjusted hazard ratio [aHR], 2.37; 95% confidence interval [CI], 1.52 to 3.68). Pharmacokinetic analyses (study 2) included 1,309 linezolid concentrations from 603 adult patients. Age, body surface area, and estimated glomerular filtration rate (eGFR) were identified as covariates of linezolid clearance. Linezolid dose reductions improved the probability of achieving optimal exposures in simulated patients with eGFR values of <60 ml/min. Thrombocytopenia occurs more frequently in patients with renal impairment receiving standard linezolid doses. Linezolid dose reduction and trough-based TDM are predicted to mitigate this treatment-limiting toxicity
Sonography for diagnosis of rotator cuff tear: Comparison with observations at surgery in 58 shoulders
- …