714 research outputs found
Evidence of improving antiretroviral therapy treatment delays: an analysis of eight years of programmatic outcomes in Blantyre, Malawi
Background: Impressive achievements have been made towards achieving universal coverage of antiretroviral therapy (ART) in sub-Saharan Africa. However, the effects of rapid ART scale-up on delays between HIV diagnosis and treatment initiation have not been well described.
Methods: A retrospective cohort study covering eight years of ART initiators (2004–2011) was conducted at Queen Elizabeth Central Hospital (QECH) in Blantyre, Malawi. The time between most recent positive HIV test and ART initiation was calculated and temporal trends in delay to initiation were described. Factors associated with time to initiation were investigated using multivariate regression analysis.
Results: From 2004–2011, there were 15,949 ART initiations at QECH (56% female; 8% children [0–10 years] and 5%adolescents [10–20 years]). Male initiators were likely to have more advanced HIV infection at initiation than female initiators (70% vs. 64% in WHO stage 3 or 4). Over the eight years studied, there were declines in treatment delay, with 2011 having the shortest delay at 36.5 days. On multivariate analysis CD4 count <50 cells/μl (adjusted geometric mean ratio [aGMR]: aGMR: 0.53, bias-corrected accelerated [BCA] 95% CI: 0.42-0.68) was associated with shorter ART treatment delay. Women (aGMR: 1.12, BCA 95% CI: 1.03-1.22) and patients diagnosed with HIV at another facility outside QECH (aGMR: 1.61, BCA 95% CI: 1.47-1.77) had significantly longer treatment delay.
Conclusions: Continued improvements in treatment delays provide evidence that universal access to ART can be achieved using the public health approach adopted by Malawi However, the longer delays for women and patients diagnosed at outlying sites emphasises the need for targeted interventions to support equitable access for these groups
Report of the Topical Group on Micro-Pattern Gaseous Detectors for Snowmass 2021
This report summarizes white papers on micro-pattern gaseous detectors
(MPGDs) that were submitted to the Instrumentation Frontier Topical Group IF05,
as part of the Snowmass 2021 decadal survey of particle physics.Comment: contribution to Snowmass 202
Visual outcomes and predictors in optic pathway glioma: a single centre study
BACKGROUND/AIMS: Optic pathway gliomas (OPGs) may cause progressive visual loss despite chemotherapy. Newer, less toxic treatments might be given earlier, depending on visual prognosis. We aimed to investigate the prognostic value of visual evoked potentials (VEP) and optical coherence tomography (OCT). METHODS: A retrospective study of OPG patients (treated 2003–2017) was conducted. Primary outcome was PEDIG category visual acuity in better and worse eyes (good = 0.7 logMAR). Binary logistic regression analysis was used to identify predictors of these outcomes. RESULTS: 60 patients (32 Neurofibromatosis type 1 [NF1] and 28 sporadic) had median presentation age 49 months (range 17–183) (NF1) and 27 months (range 4–92) (sporadic). Median follow up was 82 months (range 12–189 months). At follow up 24/32 (75%) of NF1 children and 14/28 (50%) of sporadic children had good better eye visual acuity and 11/32 (34%) of NF1 children and 15/28 (54%) of sporadics had poor worse eye acuity. Mean peripapillary retinal nerve fibre layer (RNFL) thickness predicted good better eye final acuity (OR 0.799, 95%CI 0.646–0.987, p = 0.038). Presenting with visual symptoms (OR 0.22 95% CI 0.001–0.508, p = 0.017) and poorer VEP scores (OR 2.35 95% CI 1.1–5.03, p = 0.027) predicted poor worse eye final acuity. 16 children had homonymous hemianopias at follow up, predicted by poor presenting binocular VEP score (OR 1.449 95%CI 1.052–1.995, p = 0.02). CONCLUSIONS: We found that both RNFL thickness on OCT and VEP were useful in predicting future visual acuity and vision and potentially in planning treatment. We had a high prevalence of homonymous hemianopia
K-Space at TRECVID 2008
In this paper we describe K-Space’s participation in
TRECVid 2008 in the interactive search task. For 2008
the K-Space group performed one of the largest interactive
video information retrieval experiments conducted
in a laboratory setting. We had three institutions participating
in a multi-site multi-system experiment. In
total 36 users participated, 12 each from Dublin City
University (DCU, Ireland), University of Glasgow (GU,
Scotland) and Centrum Wiskunde and Informatica (CWI,
the Netherlands). Three user interfaces were developed,
two from DCU which were also used in 2007 as well as
an interface from GU. All interfaces leveraged the same
search service. Using a latin squares arrangement, each
user conducted 12 topics, leading in total to 6 runs per
site, 18 in total. We officially submitted for evaluation 3
of these runs to NIST with an additional expert run using
a 4th system. Our submitted runs performed around
the median. In this paper we will present an overview of
the search system utilized, the experimental setup and a
preliminary analysis of our results
CYGNUS : Feasibility of a nuclear recoil observatory with directional sensitivity to dark matter and neutrinos
Now that conventional weakly interacting massive particle (WIMP) dark matter searches are approaching the neutrino floor, there has been a resurgence of interest in detectors with sensitivity to nuclear recoil directions. A large-scale directional detector is attractive in that it would have sensitivity below the neutrino floor, be capable of unambiguously establishing the galactic origin of a purported dark matter signal, and could serve a dual purpose as a neutrino observatory. We present the first detailed analysis of a 1000~m3-scale detector capable of measuring a directional nuclear recoil signal at low energies. We propose a modular and multi-site observatory consisting of time projection chambers (TPCs) filled with helium and SF6 at atmospheric pressure. Depending on the TPC readout technology, 10-20 helium recoils above 6 kevr or only 3-4 recoils above 20~\kevr would suffice to distinguish a 10~GeV WIMP signal from the solar neutrino background. High-resolution charge readout also enables powerful electron background rejection capabilities well below 10~keV. We detail background and site requirements at the 1000~m3-scale, and identify materials that require improved radiopurity. The final experiment, which we name CYGNUS-1000, will be able to observe 10-40 neutrinos from the Sun, depending on the final energy threshold. With the same exposure, the sensitivity to spin independent cross sections will extend into presently unexplored sub-10 GeV parameter space. For spin dependent interactions, already a 10~m3-scale experiment could compete with upcoming generation-two detectors, but CYGNUS-1000 would improve upon this considerably. Larger volumes would bring sensitivity to neutrinos from an even wider range of sources, including galactic supernovae, nuclear reactors, and geological processes
Should the Arteriovenous Fistula Be Created before Starting Dialysis?: A Decision Analytic Approach
Background: An arteriovenous fistula (AVF) is considered the vascular access of choice, but uncertainty exists about the\ud
optimal time for its creation in pre-dialysis patients. The aim of this study was to determine the optimal vascular access\ud
referral strategy for stage 4 (glomerular filtration rate ,30 ml/min/1.73 m2) chronic kidney disease patients using a decision\ud
analytic framework.\ud
Methods: A Markov model was created to compare two strategies: refer all stage 4 chronic kidney disease patients for an\ud
AVF versus wait until the patient starts dialysis. Data from published observational studies were used to estimate the\ud
probabilities used in the model. A Markov cohort analysis was used to determine the optimal strategy with life expectancy\ud
and quality adjusted life expectancy as the outcomes. Sensitivity analyses, including a probabilistic sensitivity analysis, were\ud
performed using Monte Carlo simulation.\ud
Results: The wait strategy results in a higher life expectancy (66.6 versus 65.9 months) and quality adjusted life expectancy\ud
(38.9 versus 38.5 quality adjusted life months) than immediate AVF creation. It was robust across all the parameters except\ud
at higher rates of progression and lower rates of ischemic steal syndrome.\ud
Conclusions: Early creation of an AVF, as recommended by most guidelines, may not be the preferred strategy in all predialysis\ud
patients. Further research on cost implications and patient preferences for treatment options needs to be done\ud
before recommending early AVF creation
Distributed situation awareness in dynamic systems: Theoretical development and application of an ergonomics methodology
The purpose of this paper is to propose foundations for a theory of situation awareness based on the analysis of interactions between agents (i.e., both human and non-human) in subsystems. This approach may help promote a better understanding of technology-mediated interaction in systems, as well as helping in the formulation of hypotheses and predictions concerning distributed situation awareness. It is proposed that agents within a system each hold their own situation awareness which may be very different from (although compatible with) other agents. It is argued that we should not always hope for, or indeed want, sharing of this awareness, as different system agents have different purposes. This view marks situation awareness as a
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dynamic and collaborative process that binds agents together on tasks on a moment-by-moment basis. Implications of this viewpoint for development of a new theory of, and accompanying methodology for, distributed situation awareness are offered
Predicting healthcare employees' participation in an office redesign program: Attitudes, norms and behavioral control
<p>Abstract</p> <p>Background</p> <p>The study examined the extent to which components based on a modified version of the theory of planned behavior explained employee participation in a new clinical office program designed to reduce patient waiting times in primary care clinics.</p> <p>Methods</p> <p>We regressed extent of employee participation on attitudes about the program, group norms, and perceived behavioral control along with individual and clinic characteristics using a hierarchical linear mixed model.</p> <p>Results</p> <p>Perceived group norms were one of the best predictors of employee participation. Attitudes about the program were also significant, but to a lesser degree. Behavioral control, however, was not a significant predictor. Respondents with at least one year of clinic tenure, or who were team leaders, first line supervisor, or managers had greater participation rates. Analysis at the clinic level indicated clinics with scores in the highest quartile clinic scores on group norms, attitudes, and behavioral control scores were significantly higher on levels of overall participation than clinics in the lowest quartile.</p> <p>Conclusion</p> <p>Findings suggest that establishing strong norms and values may influence employee participation in a change program in a group setting. Supervisory level was also significant with greater responsibility being associated with greater participation.</p
The mTOR inhibitor, everolimus (RAD001), overcomes resistance to imatinib in quiescent Ph-positive acute lymphoblastic leukemia cells
In Ph-positive (Ph+) leukemia, the quiescent cell state is one of the reasons for resistance to the BCR-ABL-kinase inhibitor, imatinib. In order to examine the mechanisms of resistance due to quiescence and the effect of the mammalian target of rapamycin inhibitor, everolimus, for such a resistant population, we used Ph+ acute lymphoblastic leukemia patient cells serially xenotransplanted into NOD/SCID/IL2rγnull (NOG) mice. Spleen cells from leukemic mice showed a higher percentage of slow-cycling G0 cells in the CD34+CD38− population compared with the CD34+CD38+ and CD34− populations. After ex vivo imatinib treatment, more residual cells were observed in the CD34+CD38− population than in the other populations. Although slow-cycling G0 cells were insensitive to imatinib in spite of BCR-ABL and CrkL dephosphorylation, combination treatment with everolimus induced substantial cell death, including that of the CD34+CD38− population, with p70-S6 K dephosphorylation and decrease of MCL-1 expression. The leukemic non-obese diabetic/severe combined immunodeficiency (NOD/SCID) mouse system with the in vivo combination treatment with imatinib and everolimus showed a decrease of tumor burden including CD34+ cells. These results imply that treatment with everolimus can overcome resistance to imatinib in Ph+ leukemia due to quiescence
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