Kidney exchanges enable transplants when a pair of a patient and an incompatible donor is matched with other similar pairs. In multi-hospital kidney exchanges pairs are pooled from multiple ...hospitals, and each hospital is able to decide which pairs to report and which to hide and match locally. Modeling the problem as a maximum matching on a random graph, we first establish that the expected benefit from pooling scales as the square-root of the number of pairs in each hospital. We design the xCM mechanism, which achieves efficiency and incentivizes hospitals of moderate-to-large size to fully report their pairs. Reciprocal pairs are crucial in the design, with the probabilistic uniform rule used to ensure incentive alignment. By grouping certain pair types into so-called virtual-reciprocal pairs, xCM extends to handle 3-cycles. We validate the performance of xCM in simulation, demonstrating its efficiency and incentive advantages over the Bonus mechanism (Ashlagi and Roth, 2014).
PurposeTo assess the preoperative features of patients with idiopathic macular hole (IMH) and vitreomacular adhesion (VMA) treated with ocriplasmin (OCP) that can predict successful ...closure.MethodData were prospectively collected on all patients with IMH treated with OCP in three British ophthalmic centres. Several preoperative variables were recorded including the IMH base diameter (BD), minimum linear diameter (MLD), and VMA width measured on spectral domain optical coherence tomography. Several other IMH indices were derived including a 'width factor', defined as the BD minus the MLD in μm. The occurrence of VMA release and hole closure were used as the main outcome measures.ResultsThirty-three patients in total with IMH were treated with OCP. Two patients developed rhegmatogenous retinal detachment and were excluded. The mean age of the remaining 31 patients was 71 years, and 71% were female. VMA release occurred in 19 of the 31 (61%) patients and macular hole closure in 11 (35%). Width factor was the most predictive feature for closure on multivariate analysis. The deviance R(2) was 67% (P<0.001). An IMH with a width factor of <60 μm had a 95% certainty of closure, whereas if >290 μm then there was less than a 5% chance of closure. Neither VMA width nor MLD alone was associated with VMA release or closure.ConclusionsPatients with macular holes where the BD was close in size to the MLD had an improved probability of closure than holes with wider base configurations.
Alignment procedure of the LHCb vertex detector Viret, S.; Parkes, C.; Gersabeck, M.
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
11/2008, Letnik:
596, Številka:
2
Journal Article
Recenzirano
Odprti dostop
LHCb is one of the four main experiments of the Large Hadron Collider (LHC) project, which will start at CERN in 2008. The experiment is primarily dedicated to B-Physics and hence requires precise ...vertex reconstruction. The silicon vertex locator (VELO) has a single hit precision of better than
10
μ
m
and is used both off-line and in the trigger. These requirements place strict constraints on its alignment. Additional challenges for the alignment arise from the detector being retracted between each fill of the LHC and from its unique circular disc
r
/
φ
strip geometry. This paper describes the track-based software alignment procedure developed for the VELO. The procedure is primarily based on a non-iterative method using a matrix inversion technique. The procedure is demonstrated with simulated events to be fast, robust and to achieve a suitable alignment precision.
Advances in molecular diagnostic technologies have enabled genetic testing in single closed-tube reactions. The purpose of this review is to highlight some of the platforms and technologies currently ...available for the homogeneous detection of targets and the application of the technologies in the clinical setting. Validation issues surrounding the technologies, which may need to be addressed before they can become widely accepted, will also be discussed.
This review discusses the principles of several of the major technologies available for performing homogeneous genetic analyses. Publications arising from the application of the technologies in a wide range of clinical areas are used to highlight and compare the potential advantages and shortcomings of the various technologies.
This review is descriptive and focuses on three areas: the technologies available for performing homogeneous analysis, the clinical applications where the technologies are being used, and validation issues surrounding the acceptance of the technologies in the general clinical setting.
This review intends to give the reader a greater understanding of the various technologies available for performing homogeneous genetic testing in the clinical laboratory. Through insight into the principles and performance characteristics underlying these technologies, the end user can evaluate their value and limitations in the clinical diagnostic setting.
Objectives
Determine if the muscle mRNA levels of three growth factors (insulin-like growth factor-1 IGF1, ciliary neurotropic factor CNTF, and vascular endothelial growth factor-D VEGFD) are ...correlated with muscle size and strength gains from resistance exercise while piloting a training program in older adults taking medications and supplements for age-associated problems.
Design
Single-arm prospective study.
Setting
US Veterans Affairs hospital.
Participants
Older (70±6 yrs) male Veterans (N=14) of US military service.
Intervention
Thirty-five sessions of high-intensity (80% one-rep max) resistance training including leg press, knee curl, and knee extension to target the thigh muscles.
Measurements
Vastus lateralis biopsies were collected and body composition (DEXA) was determined pre- and post-training. Simple Pearson correlations were used to compare training outcomes to growth factor mRNA levels and other independent variables such as medication and supplement use.
Results
Average strength increase for the group was ≥ 25% for each exercise. Subjects averaged taking numerous medications (N=5±3) and supplements (N=2±2). Of the growth factors, a significant correlation (R>0.7, P≤0.003) was only found between pre-training VEGFD and gains in lean thigh mass and extension strength. Mass and strength gains were also correlated with use of α-1 antagonists (R=0.55, P=0.04) and pre-training lean mass (R=0.56, P=0.04), respectively.
Conclusions
Muscle VEGFD, muscle mass, and use of α-1 antagonists may be predisposing factors that influence the response to training in this population of older adults but additional investigation is required to determine if these relationships are due to muscle angiogenesis and blood supply.
The LHCb upgrade Parkes, C
Journal of physics. Conference series,
05/2008, Letnik:
110, Številka:
9
Journal Article
Recenzirano
Odprti dostop
LHCb is the dedicated flavour physics experiment at the LHC. An upgrade of this experiment is proposed to significantly enhance its potential for CP violation and rare decay studies. The operational ...luminosity of the LHCb experiment is limited by its trigger capabilities, occupancy and radiation damage issues. These issues will be addressed in the LHCb upgrade, with the aim of operating at instantaneous luminosities up to a factor ten higher than the design luminosity of the initial experiment.
Irritable bowel syndrome (IBS) is a chronic disorder characterized by abdominal pain, change in bowel habit, and bloating. It has traditionally been viewed as a disorder of visceral hypersensitivity ...heavily influenced by stress, and therefore therapeutic strategies to date have largely reflected this. However, more recently, there is good evidence for a role of the gastrointestinal (GI) microbiota in its pathogenesis. Changes in fecal microbiota, the use of probiotics, the phenomenon of postinfectious IBS, and the recognition of an upregulated host immune system response suggest that an interaction between the host and GI microbiota may be important in the pathogenesis of IBS. This article explores the role of the GI microbiota in IBS and how their modification might lead to therapeutic benefit.
Summary
Background
Corticosteroids are central to inducing remission in inflammatory bowel disease (IBD) but are ineffective maintenance agents.
Aim
To benchmark steroid usage in British outpatients ...and assess factors associated with excess exposure.
Methods
We recorded steroid use in unselected IBD outpatients. Cases meeting criteria for steroid dependency or excess were blind peer reviewed to determine whether steroid prescriptions were avoidable. Associations between steroid use and patient/institutional factors were analysed.
Results
Of 1176 patients, 30% received steroids in the prior 12 months. 14.9% had steroid dependency or excess, which was more common in moderate/severe ulcerative colitis (UC) than Crohn's disease (CD) (42.6% vs 28.1%; P = .027). Steroid dependency or excess was deemed avoidable in 49.1%. The annual incidence of inappropriate steroid excess was 7.1%. Mixed‐effects logistic regression analysis revealed independent predictors of inappropriate steroid excess. The odds ratio (OR, 95%CI) for moderate/severe compared to mild/quiescent disease activity was 4.59 (1.53‐20.64) for UC and 4.60 (2.21‐12.00) for CD. In CD, lower rates of inappropriate steroid excess were found in centres with an IBD multi‐disciplinary team (OR 0.62 0.46‐0.91), whilst dedicated IBD clinics protected against inappropriate steroid excess in UC (OR 0.64, 95% CI 0.21‐0.94). The total number of GI trainees was associated with rates of inappropriate steroid excess.
Conclusions
Steroid dependency or excess occurred in 14.9% of British IBD patients (in 7.1% potentially avoidable). We demonstrated positive effects of service configurations (IBD multi‐disciplinary team, dedicated IBD clinics). Routine recording of steroid dependency or excess is feasible and should be considered a quality metric.
Linked ContentThis article is linked to Colizzo and Friedman and Selinger et al papers. To view these articles visit https://doi.org/10.1111/apt.14334 and https://doi.org/10.1111/apt.14403.
Incentivizing Deep Fixes in Software Economies Rao, Malvika; Bacon, David F.; Parkes, David C. ...
IEEE transactions on software engineering,
2020-Jan.-1, 2020-1-1, 20200101, Letnik:
46, Številka:
1
Journal Article
Recenzirano
An important question in a software economy is how to incentivize deep rather than shallow fixes. A deep fix corrects the root cause of a bug instead of suppressing the symptoms. This paper initiates ...the study of the problem of incentive design for open workflows in fixing code. We model the dynamics of the software ecosystem and introduce subsumption mechanisms. These mechanisms only make use of externally observable information in determining payments and promote competition between workers. We use a mean field equilibrium methodology to evaluate the performance of these mechanisms, demonstrating in simulation that subsumption mechanisms perform robustly across various environment configurations and satisfy important criteria for market design.
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