2,684 research outputs found
Development and application of an acceptance testing model
The process of acceptance testing large software systems for NASA has been analyzed, and an empirical planning model of the process constructed. This model gives managers accurate predictions of the staffing needed, the productivity of a test team, and the rate at which the system will pass. Applying the model to a new system shows a high level of agreement between the model and actual performance. The model also gives managers an objective measure of process improvement
Multi-elemental composition of authigenic carbonates in benthic foraminifera from the eastern Bering Sea continental margin (International Ocean Discovery Program Site U1343)
Bering Sea sediments represent exceptional archives, offering the potential to study past climates and biogeochemistry at a high resolution. However, abundant hydrocarbons of microbial origin, especially along the eastern Bering Sea continental margin, can hinder the applicability of palaeoceanographic proxies based on calcareous foraminifera, due to the formation of authigenic carbonates. Nonetheless, authigenic carbonates may also bear unique opportunities to reconstruct changes in the sedimentary redox environment.
Here we use a suite of visual and geochemical evidence from single-specimens of the shallow infaunal benthic foraminiferal species Elphidium batialis Saidova (1961), recovered from International Ocean Discovery Program (IODP) Site U1343 in the eastern Bering Sea, to investigate the influence of authigenic carbonates on the foraminiferal trace metal composition. Our results demonstrate that foraminiferal calcite tests act as a nucleation template for secondary carbonate precipitation, altering their geochemistry where organoclastic sulphate reduction and anaerobic oxidation of methane cause the formation of low- and high-Mg calcite, respectively. The authigenic carbonates can occur as encrusting on the outside and/or inside of foraminiferal tests, in the form of recrystallization of the test wall, or as banding along natural laminations within the foraminiferal test walls. In addition to Mg, authigenic carbonates are enriched in U/Ca, Mn/Ca, Fe/Ca, and Sr/Ca, depending on the redox environment that they were formed in. Our results demonstrate that site-specific U/Ca thresholds are a promising tool to distinguish between diagenetically altered and pristine foraminiferal samples, important for palaeoceanographic reconstructions utilising the primary foraminiferal geochemistry. Consistent with previous studies, U/Mn ratios of foraminifera at IODP Site U1343 increase according to their degree of diagenetic alteration, suggesting a potential response of authigenic U/Mn to the microbial activity in turn linked to the sedimentary redox environment
Creating a Professional Development Plan for a Simulation Consortium
As the United States struggles with health care reform and a nursing education system that inadequately prepares students for practice, dramatic advances in educational technology signal opportunities for both academic and practicing nurses to affect our profession as never before. Simulation technologies provide large and small institutions with the means to educate health care students and novice professionals effectively and efficiently through hands-on experience, but the costs of such a venture can be prohibitive. A simulation consortium offers a venue for different health care and educational institutions with shared goals to pool knowledge, monies, and labor toward health care education throughout a geographic area. This article details one Midwestern U.S. region's work in creating a professional development plan for a new simulation consortium
A Search for Exozodiacal Clouds with Kepler
Planets embedded within dust disks may drive the formation of large scale
clumpy dust structures by trapping dust into resonant orbits. Detection and
subsequent modeling of the dust structures would help constrain the mass and
orbit of the planet and the disk architecture, give clues to the history of the
planetary system, and provide a statistical estimate of disk asymmetry for
future exoEarth-imaging missions. Here we present the first search for these
resonant structures in the inner regions of planetary systems by analyzing the
light curves of hot Jupiter planetary candidates identified by the Kepler
mission. We detect only one candidate disk structure associated with KOI 838.01
at the 3-sigma confidence level, but subsequent radial velocity measurements
reveal that KOI 838.01 is a grazing eclipsing binary and the candidate disk
structure is a false positive. Using our null result, we place an upper limit
on the frequency of dense exozodi structures created by hot Jupiters. We find
that at the 90% confidence level, less than 21% of Kepler hot Jupiters create
resonant dust clumps that lead and trail the planet by ~90 degrees with optical
depths >~5*10^-6, which corresponds to the resonant structure expected for a
lone hot Jupiter perturbing a dynamically cold dust disk 50 times as dense as
the zodiacal cloud.Comment: 22 pages, 6 figures, Accepted for publication in Ap
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Assessing Neuronal and Astrocyte Derived Exosomes From Individuals With Mild Traumatic Brain Injury for Markers of Neurodegeneration and Cytotoxic Activity.
Mild traumatic brain injury (mTBI) disproportionately affects military service members and is very difficult to diagnose. To-date, there is currently no blood-based, diagnostic biomarker for mTBI cases with persistent post concussive symptoms. To examine the potential of neuronally-derived (NDE) and astrocytic-derived (ADE) exosome cargo proteins as biomarkers of chronic mTBI in younger adults, we examined plasma exosomes from a prospective longitudinal study of combat-related risk and resilience, marine resiliency study II (MRSII). After return from a combat-deployment participants were interviewed to assess TBI exposure while on deployment. Plasma exosomes from military service members with mTBI (mean age, 21.7 years, n = 19, avg. days since injury 151), and age-matched, controls (deployed service members who did not endorse a deployment-related TBI or a pre-deployment history of TBI; mean age, 21.95 years, n = 20) were precipitated and enriched against a neuronal adhesion protein, L1-CAM, and an astrocyte marker, glutamine aspartate transporter (GLAST) using magnetic beads to immunocapture the proteins and subsequently selected by fluorescent activated cell sorting (FACS). Extracted protein cargo from NDE and ADE preparations were quantified for protein levels implicated in TBI neuropathology by standard ELISAs and on the ultra-sensitive single molecule assay (Simoa) platform. Plasma NDE and ADE levels of Aβ42 were significantly higher while plasma NDE and ADE levels of the postsynaptic protein, neurogranin (NRGN) were significantly lower in participants endorsing mTBI exposure compared to controls with no TBI history. Plasma NDE and ADE levels of Aβ40, total tau, and neurofilament light (NFL), P-T181-tau, P-S396-tau were either undetectable or not significantly different between the two groups. In an effort to understand the pathogenetic potential of NDE and ADE cargo proteins, neuron-like cultures were treated with NDE and ADE preparations from TBI and non-TBI groups. Lastly, we determined that plasma NDE but not ADE cargo proteins from mTBI samples were found to be toxic to neuron-like recipient cells in vitro. These data support the presence of markers of neurodegeneration in NDEs of mTBI and suggest that these NDEs can be used as tools to identify pathogenic mechanisms of TBI
Treatment patterns for cancer in Western Australia: does being Indigenous make a difference?
Objective: To examine whether hospital patients with cancer who were identified as Indigenous were as likely to receive surgery for the cancer as non-Indigenous patients. Design, setting and patients: Epidemiological survey of all Western Australian (WA) patients who had a cancer registration in the state-based WA Record Linkage Project that mentioned cancer of the breast (1982–2000) or cancer of the lung or prostate (1982–2001).
Main outcome measures: The likelihoods of receiving breast-conserving surgery or mastectomy for breast cancer, lung surgery for lung cancer, or radical or non-radical prostatectomy for prostate cancer were compared between the Indigenous and non-Indigenous populations using adjusted logistic regression analyses.
Results: Indigenous people were less likely to receive surgery for their lung cancer (odds ratio [OR], 0.64; 95% CI, 0.41–0.98). Indigenous men were as likely as non- Indigenous men to receive non-radical prostatectomy (OR, 0.69; 95% CI, 0.40–1.17); only one Indigenous man out of 64 received radical prostatectomy. Indigenous women were as likely as non-Indigenous women to undergo breast-conserving surgery (OR, 0.86; 95% CI, 0.60–1.21).
Conclusions: These results indicate a different pattern of surgical care for Indigenous patients in relation to lung and prostate, but not breast, cancer. Reasons for these disparities, such as treatment choice and barriers to care, require further investigation
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The impact of mental health recovery narratives on recipients experiencing mental health problems: Qualitative analysis and change model.
BACKGROUND: Mental health recovery narratives are stories of recovery from mental health problems. Narratives may impact in helpful and harmful ways on those who receive them. The objective of this paper is to develop a change model identifying the range of possible impacts and how they occur. METHOD: Semi-structured interviews were conducted with adults with experience of mental health problems and recovery (n = 77). Participants were asked to share a mental health recovery narrative and to describe the impact of other people's recovery narratives on their own recovery. A change model was generated through iterative thematic analysis of transcripts. RESULTS: Change is initiated when a recipient develops a connection to a narrator or to the events descripted in their narrative. Change is mediated by the recipient recognising experiences shared with the narrator, noticing the achievements or difficulties of the narrator, learning how recovery happens, or experiencing emotional release. Helpful outcomes of receiving recovery narratives are connectedness, validation, hope, empowerment, appreciation, reference shift and stigma reduction. Harmful outcomes are a sense of inadequacy, disconnection, pessimism and burden. Impact is positively moderated by the perceived authenticity of the narrative, and can be reduced if the recipient is experiencing a crisis. CONCLUSIONS: Interventions that incorporate the use of recovery narratives, such as peer support, anti-stigma campaigns and bibliotherapy, can use the change model to maximise benefit and minimise harms from narratives. Interventions should incorporate a diverse range of narratives available through different mediums to enable a range of recipients to connect with and benefit from this material. Service providers using recovery narratives should preserve authenticity so as to maximise impact, for example by avoiding excessive editing
Exile Vol. XXXI No. 1
Drawing by Chris Bradley 1
How Goes the Wombat, Prithee by Jennie Benford 3
Holy Shit (for Mary) by Stephanie Athey 4-5
..... blues by Britton R. Creelman 6
Photograph (anonymous) 7
Prose by Leigh Walton 9-12
San Jacinto by Petersen S. Thomas 13
Rebuttal by Betsy Oster 15
Running Alone by Ann Townsend McMullen 16
Windows in Florence by Michael Parr 17
Rangers by Caroline Palmer 19
Salamapo by Mary Deborah Clark 20-21
Funeral by J. K. Rand 22
Deeds Give No Title by Douglas Jones 23
Be Careful, There\u27s a Straight Bar Next Door by Karen J. Hall 25
The Rivers of Saigon by Alex Dickson 26
2 Sketches by Alfred Sturla Bodvarsson 27
Upon the Occasion of Reading 236 sonnets at One Sitting by Jeff Masten 28
I just believe in Me by Rob Jackson 29
Close by Stephanie Athey 31
Teller by Katherine Fox Reynolds 32
Woman in Greece by Michael Parr 33
Part of the Job by Joan DeWitt 35-44
Contributor Notes 46
Editorial decision is shared equally among the seven member editorial board. -title page
Polymorphous: Cover Lithograph by Aimee Creelman - title pag
Short course daily prednisolone therapy during an upper respiratory tract infection in children with relapsing steroid-sensitive nephrotic syndrome (PREDNOS 2):protocol for a randomised controlled trial
BACKGROUND: Relapses of childhood steroid-sensitive nephrotic syndrome (SSNS) are treated with a 4- to 8-week course of high-dose oral prednisolone, which may be associated with significant adverse effects. There is a clear association between upper respiratory tract infection (URTI) and relapse development. Previous studies in developing nations have suggested that introducing a 5- to 7-day course of daily prednisolone during an URTI may prevent a relapse developing and the need for a treatment course of high-dose prednisolone. The aim of PREDNOS 2 is to evaluate the effectiveness of a 6-day course of daily prednisolone therapy during an URTI in reducing the development of a subsequent relapse in a developed nation.METHODS/DESIGN: The subjects will be 300 children with relapsing SSNS (≥2 relapses in preceding year), who will be randomised to receive either a 6-day course of daily prednisolone or no change to their current therapy (with the use of placebo to double blind) each time they develop an URTI over 12 months. A strict definition for URTI will be used. Subjects will be reviewed at 3, 6, 9 and 12 months to capture data regarding relapse history, ongoing therapy and adverse effect profile, including behavioural problems and quality of life. A formal health economic analysis will also be performed. The primary end point of the study will be the incidence of URTI-related relapse (3 days of Albustix +++) following the first infection during the 12-month follow-up period. DNA and RNA samples will be collected to identify a potential genetic cause for the disease. Subjects will be recruited from over 100 UK centres with the assistance of the Medicines for Children Research Network. PREDNOS 2 is funded by the National Institute for Health Research Health Technology Assessment Programme (11/129/261).DISCUSSION: We propose that PREDNOS 2 will be a pivotal study that will inform the future standard of care for children with SSNS. If it is possible to reduce the disease relapse rate effectively and safely, this will reduce the morbidity and cost associated with drug treatment, notwithstanding hospital admission and parental absence from employment.TRIAL REGISTRATION: Current Controlled Trials (ISRCTN10900733).</p
Daily low-dose prednisolone to prevent relapse of steroid-sensitive nephrotic syndrome in children with an upper respiratory tract infection:PREDNOS2 RCT
BACKGROUND: Most children with steroid-sensitive nephrotic syndrome have relapses that are triggered by upper respiratory tract infections. Four small trials, mostly in children already taking maintenance corticosteroid in countries of different upper respiratory tract infection epidemiology, showed that giving daily low-dose prednisone/prednisolone for 5-7 days during an upper respiratory tract infection reduces the risk of relapse. OBJECTIVES: To determine if these findings were replicated in a large UK population of children with relapsing steroid-sensitive nephrotic syndrome on different background medication or none. DESIGN: A randomised double-blind placebo-controlled trial, including a cost-effectiveness analysis. SETTING: A total of 122 UK paediatric departments, of which 91 recruited patients. PARTICIPANTS: A total of 365 children with relapsing steroid-sensitive nephrotic syndrome (mean age 7.6 ± 3.5 years) were randomised (1 : 1) according to a minimisation algorithm based on background treatment. Eighty children completed 12 months of follow-up without an upper respiratory tract infection. Thirty-two children were withdrawn from the trial (14 prior to an upper respiratory tract infection), leaving a modified intention-to-treat analysis population of 271 children (134 and 137 children in the prednisolone and placebo arms, respectively). INTERVENTIONS: At the start of an upper respiratory tract infection, children received 6 days of prednisolone (15 mg/m2) or an equivalent dose of placebo. MAIN OUTCOME MEASURES: The primary outcome was the incidence of first upper respiratory tract infection-related relapse following any upper respiratory tract infection over 12 months. The secondary outcomes were the overall rate of relapse, changes in background treatment, cumulative dose of prednisolone, rates of serious adverse events, incidence of corticosteroid adverse effects, change in Achenbach Child Behaviour Checklist score and quality of life. Analysis was by intention-to-treat principle. The cost-effectiveness analysis used trial data and a decision-analytic model to estimate quality-adjusted life-years and costs at 1 year, which were then extrapolated over 16 years. RESULTS: There were 384 upper respiratory tract infections and 82 upper respiratory tract infection-related relapses in the prednisolone arm, and 407 upper respiratory tract infections and 82 upper respiratory tract infection-related relapses in the placebo arm. The number of patients experiencing an upper respiratory tract infection-related relapse was 56 (42.7%) and 58 (44.3%) in the prednisolone and placebo arms, respectively (adjusted risk difference -0.024, 95% confidence interval -0.14 to 0.09; p = 0.70). There was no evidence that the treatment effect differed when data were analysed according to background treatment. There were no significant differences in secondary outcomes between treatment arms. Giving daily prednisolone at the time of an upper respiratory tract infection was associated with increased quality-adjusted life-years (0.9427 vs. 0.9424) and decreased average costs (£252 vs. £254), when compared with standard care. The cost saving was driven by background therapy and hospitalisations after relapse. The finding was robust to sensitivity analysis. LIMITATIONS: A larger number of children than expected did not have an upper respiratory tract infection and the sample size attrition rate was adjusted accordingly during the trial. CONCLUSIONS: The clinical analysis indicated that giving 6 days of daily low-dose prednisolone at the time of an upper respiratory tract infection does not reduce the risk of relapse of steroid-sensitive nephrotic syndrome in UK children. However, there was an economic benefit from costs associated with background therapy and relapse, and the health-related quality-of-life impact of having a relapse. FUTURE WORK: Further work is needed to investigate the clinical and health economic impact of relapses, interethnic differences in treatment response, the effect of different corticosteroid regimens in treating relapses, and the pathogenesis of individual viral infections and their effect on steroid-sensitive nephrotic syndrome. TRIAL REGISTRATION: Current Controlled Trials ISRCTN10900733 and EudraCT 2012-003476-39. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 26, No. 3. See the NIHR Journals Library website for further project information
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