778 research outputs found
A New Light Higgs Boson and Short-Baseline Neutrino Anomalies
The low-energy excesses observed by the MiniBooNE experiment have, to date,
defied a convinc- ing explanation under the standard model even with
accommodation for non-zero neutrino mass. In this paper we explore a new
oscillation mechanism to explain these anomalies, invoking a light neu-
trinophilic Higgs boson, conceived to induce a low Dirac neutrino mass in
accord with experimental limits. Beam neutrinos forward-scattering off of a
locally over-dense relic neutrino background give rise to a novel matter-effect
with an energy-specific resonance. An enhanced oscillation around this
resonance peak produces flavor transitions which are highly consistent with the
MiniBooNE neutrino- and antineutrino-mode data sets. The model provides
substantially improved values beyond either the no-oscillation
hypothesis or the more commonly explored 3+1 sterile neutrino hy- pothesis.
This mechanism would introduce distinctive signatures at each baseline in the
upcoming SBN program at Fermilab, presenting opportunities for further
exploration.Comment: 11 pages, 6 figures, submitted to PR
Sex differences in exercise-induced diaphragmatic fatigue in endurance-trained athletes
There is evidence that female athletes may be more susceptible to exercise-induced arterial hypoxemia and expiratory flow limitation and have greater increases in operational lung volumes during exercise relative to men. These pulmonary limitations may ultimately lead to greater levels of diaphragmatic fatigue in women. Accordingly, the purpose of this study was to determine whether there are sex differences in the prevalence and severity of exercise-induced diaphragmatic fatigue in 38 healthy endurance-trained men (n = 19; maximal aerobic capacity = 64.0 ± 1.9 ml·kg–1·min–1) and women (n = 19; maximal aerobic capacity = 57.1 ± 1.5 ml·kg–1·min–1). Transdiaphragmatic pressure (Pdi) was calculated as the difference between gastric and esophageal pressures. Inspiratory pressure-time products of the diaphragm and esophagus were calculated as the product of breathing frequency and the Pdi and esophageal pressure time integrals, respectively. Cervical magnetic stimulation was used to measure potentiated Pdi twitches (Pdi,tw) before and 10, 30, and 60 min after a constant-load cycling test performed at 90% of peak work rate until exhaustion. Diaphragm fatigue was considered present if there was a 15% reduction in Pdi,tw after exercise. Diaphragm fatigue occurred in 11 of 19 men (58%) and 8 of 19 women (42%). The percent drop in Pdi,tw at 10, 30, and 60 min after exercise in men (n = 11) was 30.6 ± 2.3, 20.7 ± 3.2, and 13.3 ± 4.5%, respectively, whereas results in women (n = 8) were 21.0 ± 2.1, 11.6 ± 2.9, and 9.7 ± 4.2%, respectively, with sex differences occurring at 10 and 30 min (P < 0.05). Men continued to have a reduced contribution of the diaphragm to total inspiratory force output (pressure-time product of the diaphragm/pressure-time product of the esophagus) during exercise, whereas diaphragmatic contribution in women changed very little over time. The findings from this study point to a female diaphragm that is more resistant to fatigue relative to their male counterparts
PRM25 HBA1C Control Predictive Validity of Four Self-Reported Measures of Antidiabetes Medication Adherence
Factors associated with antidiabetic medication non-adherence in patients with incident comorbid depression
Aim To identify factors associated with antidiabetic drug (AD) non-adherence among patients with type 2 diabetes and depression. Study Design and Settings We conducted a population-based retrospective cohort study among new AD users with a diagnosis of depression following AD initiation. We used public health insurance data from Quebec. The dependent variable was non-adherence (i.e., < 90% of days covered by ≥ 1 AD) in the year after a depression diagnosis. Different sociodemographic, clinical and medication-related variables were assessed as potential factors of non-adherence to AD treatment. We performed univariate and multivariate logistic regressions. Results We identified 3106 new users of ADs with a diagnosis of depression between 2000 and 2006. Of these individuals, 52% were considered non-adherent to their ADs. Baseline non-adherence, younger age, the addition of another AD to the initial treatment, < 4 drug claims, visits with several different physicians, high socioeconomic status, and a small number of diabetes complications were associated with AD non-adherence. Conclusions The factors identified in the present study may help clinicians recognize patients with type 2 diabetes and incident depression at increased risk for non-adherence. In these patients, close follow-up and targeted interventions could help improve adherence to AD treatment, improve glycemic control and reduce complications
Improving the light collection efficiency of silicon photomultipliers through the use of metalenses
Metalenses are optical devices that implement nanostructures as phase shifters to focus incident light. Their compactness and simple fabrication make them a potential cost-effective solution for increasing light collection efficiency in particle detectors with limited photosensitive area coverage. Here we report on the characterization and performance of metalenses in increasing the light collection efficiency of silicon photomultipliers (SiPM) of various sizes using an LED of 630 nm, and find a six to seven-fold increase in signal for a 1.3×1.3 mm² SiPM when coupled with a 10-mm-diameter metalens manufactured using deep ultraviolet stepper lithography. Such improvements could be valuable for future generations of particle detectors, particularly those employed in rare-event searches such as dark matter and neutrinoless double beta decay
Pathogenesis of hyperinflation in chronic obstructive pulmonary disease
Chronic obstructive pulmonary disease (COPD) is a preventable and treatable lung disease characterized by airflow limitation that is not fully reversible. In a significant proportion of patients with COPD, reduced lung elastic recoil combined with expiratory flow limitation leads to lung hyperinflation during the course of the disease. Development of hyperinflation during the course of COPD is insidious. Dynamic hyperinflation is highly prevalent in the advanced stages of COPD, and new evidence suggests that it also occurs in many patients with mild disease, independently of the presence of resting hyperinflation. Hyperinflation is clinically relevant for patients with COPD mainly because it contributes to dyspnea, exercise intolerance, skeletal muscle limitations, morbidity, and reduced physical activity levels associated with the disease. Various pharmacological and nonpharmacological interventions have been shown to reduce hyperinflation and delay the onset of ventilatory limitation in patients with COPD. The aim of this review is to address the more recent literature regarding the pathogenesis, assessment, and management of both static and dynamic lung hyperinflation in patients with COPD. We also address the influence of biological sex and obesity and new developments in our understanding of hyperinflation in patients with mild COPD and its evolution during progression of the disease
Construction and Assembly of the Wire Planes for the MicroBooNE Time Projection Chamber
In this paper we describe how the readout planes for the MicroBooNE Time
Projection Chamber were constructed, assembled and installed. We present the
individual wire preparation using semi-automatic winding machines and the
assembly of wire carrier boards. The details of the wire installation on the
detector frame and the tensioning of the wires are given. A strict quality
assurance plan ensured the integrity of the readout planes. The different tests
performed at all stages of construction and installation provided crucial
information to achieve the successful realisation of the MicroBooNE wire
planes.Comment: 24 pages, 22 figures, accepted for publication as Technical Report in
JINS
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