10,453 research outputs found

    Prospecting Period Measurements with LSST - Low Mass X-ray Binaries as a Test Case

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    The Large Synoptic Survey Telescope (LSST) will provide for unbiased sampling of variability properties of objects with rr mag << 24. This should allow for those objects whose variations reveal their orbital periods (PorbP_{orb}), such as low mass X-ray binaries (LMXBs) and related objects, to be examined in much greater detail and with uniform systematic sampling. However, the baseline LSST observing strategy has temporal sampling that is not optimised for such work in the Galaxy. Here we assess four candidate observing strategies for measurement of PorbP_{orb} in the range 10 minutes to 50 days. We simulate multi-filter quiescent LMXB lightcurves including ellipsoidal modulation and stochastic flaring, and then sample these using LSST's operations simulator (OpSim) over the (mag, PorbP_{orb}) parameter space, and over five sightlines sampling a range of possible reddening values. The percentage of simulated parameter space with correctly returned periods ranges from ∼\sim23 %, for the current baseline strategy, to ∼\sim70 % for the two simulated specialist strategies. Convolving these results with a PorbP_{orb} distribution, a modelled Galactic spatial distribution and reddening maps, we conservatively estimate that the most recent version of the LSST baseline strategy will allow PorbP_{orb} determination for ∼\sim18 % of the Milky Way's LMXB population, whereas strategies that do not reduce observations of the Galactic Plane can improve this dramatically to ∼\sim32 %. This increase would allow characterisation of the full binary population by breaking degeneracies between suggested PorbP_{orb} distributions in the literature. Our results can be used in the ongoing assessment of the effectiveness of various potential cadencing strategies.Comment: Replacement after addressing minor corrections from the referee - mainly improvements in clarificatio

    Preventing Isolated Perioperative Reintubation: Who is at highest risk?

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    Objectives: 1. We aim to characterize IPR nationally through a retrospective review of the National Surgical Quality Improvement Program participant user file (NSQIP PUF). 2.Identify risk factors for IPR including analysis of procedure type and preoperative characteristics.https://jdc.jefferson.edu/patientsafetyposters/1041/thumbnail.jp

    African American men with low-grade prostate cancer have increased disease recurrence after prostatectomy compared with Caucasian men.

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    PURPOSE: To explore whether disparities in outcomes exist between African American (AA) and Caucasian (CS) men with low-grade prostate cancer and similar cancer of the prostate risk assessment-postsurgery (CAPRA-S) features following prostatectomy (RP). METHODS: The overall cohort consisted of 1,265 men (234 AA and 1,031 CS) who met the National comprehensive cancer network criteria for low- to intermediate-risk prostate cancer and underwent RP between 1990 and 2012. We first evaluated whether clinical factors were associated with adverse pathologic outcomes and freedom from biochemical failure (FFbF) using the entire cohort. Next, we studied a subset of 705 men (112 AA and 593 CS) who had pathologic Gleason score≤6 (low-grade disease). Using this cohort, we determined whether race affected FFbF in men with RP-proven low-grade disease and similar CAPRA-S scores. RESULTS: With a median follow-up time of 27 months, the overall 7-year FFbF rate was 86% vs. 79% in CS and AA men, respectively (P = 0.035). There was no significant difference in one or more adverse pathologic features between CS vs. AA men (27% vs. 31%; P = 0.35) or CAPRA-S score (P = 0.28). In the subset analysis of patients with low-grade disease, AA race was associated with worse FFbF outcomes (P = 0.002). Furthermore, AA race was a significant predictor of FFbF in men with low-grade disease (hazard ratio = 2.01, 95% CI: 1.08-3.72; P = 0.029). CONCLUSIONS: AA race is a predictor of worse FFbF outcomes in men with low-grade disease after RP. These results suggest that a subset of AA men with low-grade disease may benefit from more aggressive treatment

    Mutation signature analysis identifies increased mutation caused by tobacco smoke associated DNA adducts in larynx squamous cell carcinoma compared with oral cavity and oropharynx.

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    Squamous cell carcinomas of the head and neck (HNSCC) arise from mucosal keratinocytes of the upper aero-digestive tract. Despite a common cell of origin and similar driver-gene mutations which divert cell fate from differentiation to proliferation, HNSCC are considered a heterogeneous group of tumors categorized by site of origin within the aero-digestive mucosa, and the presence or absence of HPV infection. Tobacco use is a major driver of carcinogenesis in HNSCC and is a poor prognosticator that has previously been associated with poor immune cell infiltration and higher mutation numbers. Here, we study patterns of mutations in HNSCC that are derived from the specific nucleotide changes and their surrounding nucleotide context (also known as mutation signatures). We identify that mutations linked to DNA adducts associated with tobacco smoke exposure are predominantly found in the larynx. Presence of this class of mutation, termed COSMIC signature 4, is responsible for the increased burden of mutation in this anatomical sub-site. In addition, we show that another mutation pattern, COSMIC signature 5, is positively associated with age in HNSCC from non-smokers and that larynx SCC from non-smokers have a greater number of signature 5 mutations compared with other HNSCC sub-sites. Immunohistochemistry demonstrates a significantly lower Ki-67 proliferation index in size matched larynx SCC compared with oral cavity SCC and oropharynx SCC. Collectively, these observations support a model where larynx SCC are characterized by slower growth and increased susceptibility to mutations from tobacco carcinogen DNA adducts

    How good are we at determining risk? Quantifying the accuracy of clinician determined risk for VTE prophylaxis

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    Objectives: Create and validate a simple tool for concurrent audits of risk stratification, compliance and documentation Evaluate accuracy of clinician risk stratification and prophylatic ordering practice compared with a standardized Caprini RAM across different assigned risk categories Provide recommendations for EPIC VTE Prophylaxis CDS Developmenthttps://jdc.jefferson.edu/patientsafetyposters/1050/thumbnail.jp

    Quantifying Patient Reported and Documented Compliance with Adjuncts to Venous Thromboembolism Prophylaxis

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    Objectives: 1. Measure patient compliance with pharmacologic, mechanical and ambulatory prophylactic measures. 2. Evaluate for agreement between nursing documentation and patient reported compliance with mechanical and ambulatory prophylactic measures.https://jdc.jefferson.edu/patientsafetyposters/1042/thumbnail.jp

    Quiet in the Operating Room! Team STEPPS and OR Distractions

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    Background and Objective: From the moment that a patient enters the operating room to the time that they are brought to the post anesthesia care unit, a distraction has the potential to lead to an adverse outcome for the patient. During the critical portions of the surgery, it is even more important for all members of the operating staff to be focused and engaging in safe practices. Distractions in the operating room can hinder safe communication and potentially endanger patient safety. Team training has been shown to both improve team communication and reduce distractions. The objective of this project was using Team STEPPS training to reduce distractions during the critical portions of surgery, defined as the time of anesthesia induction, the time out, and the time of emergence from anesthesiahttps://jdc.jefferson.edu/patientsafetyposters/1060/thumbnail.jp

    Subclinical infection of macaques and baboons with a baboon simarterivirus

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    Simarteriviruses (Arteriviridae: Simarterivirinae) are commonly found at high titers in the blood of African monkeys but do not cause overt disease in these hosts. In contrast, simarteriviruses cause severe disease in Asian macaques upon accidental or experimental transmission. Here, we sought to better understand the host-dependent drivers of simarterivirus pathogenesis by infecting olive baboons (n = 4) and rhesus monkeys (n = 4) with the simarterivirus Southwest baboon virus 1 (SWBV-1). Surprisingly, none of the animals in our study showed signs of disease following SWBV-1 inoculation. Three animals (two rhesus monkeys and one olive baboon) became infected and sustained high levels of SWBV-1 viremia for the duration of the study. The course of SWBV-1 infection was highly predictable: plasma viremia peaked between 1 × 107 and 1 × 108 vRNA copies/mL at 3–10 days post-inoculation, which was followed by a relative nadir and then establishment of a stable set-point between 1 × 106 and 1 × 107 vRNA copies/mL for the remainder of the study (56 days). We characterized cellular and antibody responses to SWBV-1 infection in these animals, demonstrating that macaques and baboons mount similar responses to SWBV-1 infection, yet these responses are ineffective at clearing SWBV-1 infection. SWBV-1 sequencing revealed the accumulation of non-synonymous mutations in a region of the genome that corresponds to an immunodominant epitope in the simarterivirus major envelope glycoprotein GP5, which likely contribute to viral persistence by enabling escape from host antibodies
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