Measurement of the ^{13}C(α, n_{0})^{16}O Differential Cross Section from 0.8 to 6.5 MeV

The cross section of the ^{13}C(α,n)^{16}O reaction is needed for nuclear astrophysics and applications to a precision of 10% or better, yet inconsistencies among 50 years of experimental studies currently lead to an uncertainty of ≈15%. Using a state-of-the-art neutron detection array, we have performed a high resolution differential cross section study covering a broad energy range. These measurements result in a dramatic improvement in the extrapolation of the cross section to stellar energies potentially reducing the uncertainty to ≈5% and resolving long standing discrepancies in higher energy data.

Lifestyle behaviors among Canadian nurses working night shifts in the COVID-19 era: a pilot study

Abstract

Working night shifts has been associated with negative mental health consequences such as depression, anxiety, and sleep problems. The objectives of this study were to determine the lifestyle behaviors (prevalence of nicotine, caffeine, cannabis, sleep-promoting medication, and alcohol use) and the association between job stress, sleep quality, anxiety, and depression among registered nurses working night shifts in the Canadian province of Saskatchewan in the COVID-19 era. Twenty-two registered nurses ranging from ages 25-65 that work permanent or rotating night shifts participated in an online survey from April 11th to July 15th, 2022. The results showed a strong positive association between sleep disturbance, and depression r (19) = 0.50, [p = 0.029, 95% CI, 0.06, 0.78]. A positive correlation was found between higher levels of reported anxiety and sleep disturbance r (19) = 0.69, [p = 0.001, 95% CI, 0.34, 0.87]. There was a positive correlation between depression and occupational exhaustion r (17) = 0.56, [p = 0.021, 95% CI, 0.10, 0.82]. Anxiety was significantly related to occupational exhaustion r (17) = 0.65, [p = 0.005, 95% CI, 0.24, 0.86] and depersonalization r (17) = 0.52, [p = 0.005, 95% CI, 0.06, 0.80], but not significantly related to personal accomplishment r (17) = -0.34, [p = 0.185, 95% CI, -0.70, 0.17]. In conclusion, a sample of Canadian nurses working night shifts in the province of Saskatchewan during the COVID-19 pandemic showed a significant positive relationship among sleep disturbance, anxiety, and depression. Furthermore, most nurses reported using at least one or more of the following substances: sleep-promoting medication, nicotine, alcohol, and cannabis.

A review of common natural disasters as analogs for asteroid impact effects and cascading hazards

Modern civilization has no collective experience with possible wide-ranging effects from a medium-sized asteroid impactor. Currently, modeling efforts that predict initial effects from a meteor impact or airburst provide needed information for initial preparation and evacuation plans, but longer-term cascading hazards are not typically considered. However, more common natural disasters, such as volcanic eruptions, earthquakes, wildfires, dust storms, and hurricanes, are likely analogs that can provide the scope and scale of these potential effects. These events, especially the larger events with cascading effects, are key for understanding the scope and complexity of mitigation, relief, and recovery efforts for a medium-sized asteroid impact event. This paper reviews the initial and cascading effects of these natural hazards, describes the state of the art for modeling these hazards, and discusses the relevance of these hazards to expected long-term effects of an asteroid impact. Emergency managers, resource managers and planners, and research scientists involved in mitigation and recovery efforts would likely derive significant benefit from a framework linking multiple hazard models to provide a seamless sequence of related forecasts.

Measurement of Low-Energy Resonance Strengths in the ^{18}O(α,γ)^{22}Ne Reaction

The ^{18}O(α,γ)^{22}Ne reaction is an essential part of a reaction chain that produces the ^{22}Ne(α,n)^{25}Mg neutron source for both the weak and main components of the slow neutron-capture process. At temperatures of stellar helium burning, the astrophysically relevant resonances in the ^{18}O(α,γ)^{22}Ne reaction that dominate the reaction rate occur at α particle energies E_{lab} of 472 and 569 keV. However, previous experiments have shown the strengths of these two resonances to be very weak, and only upper limits or partial resonance strengths could be obtained. This Letter reports the first direct measurement of the total resonance strength for the 472- and 569-keV resonances, 0.26±0.05 and 0.63±0.30  μeV, respectively. New resonance strengths for the resonances at α particle energies of 662.1, 749.9, and 767.6 keV are also provided. These results were achieved in an experiment optimized for background suppression and detection efficiency. The experiment was performed at the Sanford Underground Research Facility, in the 4850-foot underground cavity dedicated to the Compact Accelerator System for Performing Astrophysical Research. The experimental end station used the γ-summing High EffiCiency TOtal absorption spectrometeR. Compared to previous works, the results decrease the stellar reaction rate by as much as ≈46_{-11}^{+6}% in the relevant temperature range of stellar helium burning.

New ^{13}C(α,n)^{16}O Cross Section with Implications for Neutrino Mixing and Geoneutrino Measurements

Precise antineutrino measurements are very sensitive to proper background characterization. We present an improved measurement of the ^{13}C(α,n)^{16}O reaction cross section which constitutes significant background for large ν[over ¯] detectors. We greatly improve the precision and accuracy by utilizing a setup that is sensitive to the neutron energies while making measurements of the excited state transitions via secondary γ-ray detection. Our results shows a 54% reduction in the background contributions from the ^{16}O(3^{-},6.13  MeV) state used in the KamLAND analysis.

Perioperative intravenous contrast administration and the incidence of acute kidney injury after major gastrointestinal surgery: prospective, multicentre cohort study

BACKGROUND

This study aimed to determine the impact of preoperative exposure to intravenous contrast for CT and the risk of developing postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery.

METHODS

This prospective, multicentre cohort study included adults undergoing gastrointestinal resection, stoma reversal or liver resection. Both elective and emergency procedures were included. Preoperative exposure to intravenous contrast was defined as exposure to contrast administered for the purposes of CT up to 7 days before surgery. The primary endpoint was the rate of AKI within 7 days. Propensity score-matched models were adjusted for patient, disease and operative variables. In a sensitivity analysis, a propensity score-matched model explored the association between preoperative exposure to contrast and AKI in the first 48 h after surgery.

RESULTS

A total of 5378 patients were included across 173 centres. Overall, 1249 patients (23·2 per cent) received intravenous contrast. The overall rate of AKI within 7 days of surgery was 13·4 per cent (718 of 5378). In the propensity score-matched model, preoperative exposure to contrast was not associated with AKI within 7 days (odds ratio (OR) 0·95, 95 per cent c.i. 0·73 to 1·21; P = 0·669). The sensitivity analysis showed no association between preoperative contrast administration and AKI within 48 h after operation (OR 1·09, 0·84 to 1·41; P = 0·498).

CONCLUSION

There was no association between preoperative intravenous contrast administered for CT up to 7 days before surgery and postoperative AKI. Risk of contrast-induced nephropathy should not be used as a reason to avoid contrast-enhanced CT.

Perioperative outcomes of women with and without class III obesity undergoing hysterectomy for endometrioid endometrial cancer: A population-based study

OBJECTIVE

Population-based data on perioperative complications among women with endometrial cancer and severe obesity are lacking. We evaluated 30-day complication rates among women with and without class III obesity (body mass index ≥ 40 kg/m²) undergoing primary surgical management for endometrioid endometrial cancer (EEC), and how outcomes differed according to surgical approach (open vs. minimally invasive).

METHODS

We performed a retrospective population-based cohort study of women with EEC undergoing hysterectomy in Ontario, Canada, between 2006 and 2015. We evaluated perioperative complications in the whole cohort, and in a 1:1 matched analysis using hard and propensity score matching to ensure similar distributions of patient, tumour, provider and institution-level factors between women with and without class III obesity (identified using a surgical billing code). The primary outcome of interest was the 30-day perioperative complication rate.

RESULTS

12,112 women met inclusion criteria; 2697 (22.3%) had class III obesity. We matched 2320 (86%) women with class III obesity to those without. The composite complication rate was significantly higher among women with class III obesity (23.2% vs. 18.4%, standardized mean difference [SMD] = 0.12), primarily due to wound infection/disruption (12.1% vs. 6.2%). There was no difference in outcomes for women with and without class III obesity when a minimally invasive approach was used.

CONCLUSIONS

Wound infection/disruption was increased for women with class III obesity compared to women without. Otherwise, perioperative complications were similar between the matched pairs. When minimally invasive approaches were used, women with class III obesity had a similar risk of complications as women without obesity.

The face of postural tachycardia syndrome - insights from a large cross-sectional online community-based survey

BACKGROUND

Patients with postural tachycardia syndrome (POTS) experience chronic symptoms of orthostatic intolerance. There are minimal data detailing the demographics, clinical features and clinical course of this condition. This online, community-based survey highlights patients' experience with POTS. It consists of the largest sample of POTS patients reported to date.

OBJECTIVES

To describe the demographics, past medical history, medications, treatments and diagnostic journey for patients living with POTS.

METHODS

Postural tachycardia syndrome patients completed an online, community-based, cross-sectional survey. Participants were excluded if they had not received a diagnosis of POTS from a physician. The questions focused on the patient experience and journey, rather than physiological responses.

RESULTS

The final analysis included 4835 participants. POTS predominantly affects white (93%) females (94%) of childbearing age, with approximately half developing symptoms in adolescence (mode 14 years). POTS is a chronic multisystem disorder involving a broad array of symptoms, with many patients diagnosed with comorbidities in addition to POTS. POTS patients often experience lengthy delays [median (interquartile range) 24 (6-72) months] and misdiagnosis, but the diagnostic delay is improving. POTS patients can present with a myriad of symptoms most commonly including lightheadedness (99%), tachycardia (97%), presyncope (94%), headache (94%) and difficulty concentrating (94%).

CONCLUSIONS

These data provide important insights into the background, clinical features and diagnostic journey of patients suffering from POTS. These data should serve as an essential step for moving forward with future studies aimed at early and accurate diagnoses of these patients leading to appropriate treatments for their symptoms.

Implementing Frailty Measures in the Canadian Healthcare System

Canadian healthcare is changing to include individuals living with frailty, but frailty must be better operationalized and better framed by sound data standards and policy. Frailty results from deficit accumulation in multiple body systems, with exaggerated vulnerability to external stressors. A growing consensus on defining frailty sets the stage for consensus on operationalization and widespread implementation in care settings. Frailty measurement is not yet integrated into daily clinical practice in Canada. Here, we will present how this integration might occur. We hope to demonstrate that implementation must appeal to inter-professional practice needs in different settings or circumstances. In some settings, methods for frailty case finding are expected to evolve as deemed to be most appropriate to the front-line users. In this "hands-off" approach, care providers, supported by emerging knowledge translation on frailty operationalization, would be informed by their setting and local practices to establish patterns of ad hoc case finding and component definition of frailty. This more nimble case finding strategy would be opportunistic, and would appeal to expert clinicians and self-directed teams who emphasize an individualized health care experience for their patients. In other settings, we can shape frailty case finding by building care algorithms around existing standardized practices and data repositories, leading to a systematic application of frailty measures and a more coordinated process of component definition and care protocols. Here, recommended instruments and data standards must be endorsed by health networks locally, provincially and nationally. The interRAI suite of assessment instruments has pan-Canadian standards in place and its pervasiveness makes it the most obvious starting point, especially in home care and long-term care. We anticipate the evolution of an integrated model informed by stakeholders and settings, where policy makers focus on system supports for frailty case finding, while front-line clinicians use case finding strategies to pinpoint and act on key frailty components.

Measurement of rivaroxaban concentrations demonstrates lack of clinical utility of a PT, dPT and APTT test in estimating levels

INTRODUCTION

Rivaroxaban concentrations were measured in 127 inpatient samples using an HPLC-MS/MS assay.

METHODS

We compared this measurement with a calibrated anti-Xa assay and performed PT, aPTT and dilute PT tests to assess the value of clot-based assays in clinical decision-making.

RESULTS

The correlation between the anti-Xa assay and the HPLC-MS/MS at therapeutic concentrations was strong (R²  = 0.98). The PT, RecombiPlasTin 2G, and aPTT, Actin FS, showed a linear dose-response but poor correlation (R²  = 0.32 and 0.44, respectively) and at dilutions of 1 in 150 to 1 in 750 the dilute PT assay also showed poor correlation with rivaroxaban concentrations measured by specific assays. A normal PT or aPTT alone did not identify a likely safe rivaroxaban concentration to allow surgery or invasive procedures, but the combination of normal PT and aPTT identified a group of patients with rivaroxaban levels less than 90 ng/mL. Combined normal PT and aPTT had specificity and sensitivity of 0.97 (95% CI 0.92-0.99) and 0.37 (95% CI 0.1-0.74) for a rivaroxaban concentration < 32 ng/mL.

CONCLUSIONS

The PT and aPTT show poor correlation with rivaroxaban levels measured by calibrated anti-Xa and HPLC-MS/MS assays. A normal combined PT and APTT identified low rivaroxaban levels with high specificity but lacked sensitivity. The dPT assay at several dilutions could not be used to quantify rivaroxaban in clinical samples. The utility of these PT, aPTT and dilute PT assays in a clinical setting is very limited, and results generated must be interpreted with caution.

Experimental measurement of the 12C+16O fusion cross sections at astrophysical energies

The total cross sections of the 12C+16O fusion have been experimentally determined at low energies to investigate the role of this reaction during late stellar evolution burning phases. A high-intensity oxygen beam was produced by the 5MV pelletron accelerator at the University of Notre Dame impinging on a thick ultra-pure graphite target. Protons and γ-rays were measured simultaneously in the center-of-mass energy range from 3.64 to 5.01 MeV, using strip silicon and HPGe detectors. Statistical model calculations were employed to interpret the experimental results. A new broad resonance-like structure is observed for the 12C+16O reaction, and a decreasing trend of its S-factor towards low energies is found.

Predicting the diagnosis of autism in adults using the Autism-Spectrum Quotient (AQ) questionnaire

BACKGROUND

Many adults with autism spectrum disorder (ASD) remain undiagnosed. Specialist assessment clinics enable the detection of these cases, but such services are often overstretched. It has been proposed that unnecessary referrals to these services could be reduced by prioritizing individuals who score highly on the Autism-Spectrum Quotient (AQ), a self-report questionnaire measure of autistic traits. However, the ability of the AQ to predict who will go on to receive a diagnosis of ASD in adults is unclear.

METHOD

We studied 476 adults, seen consecutively at a national ASD diagnostic referral service for suspected ASD. We tested AQ scores as predictors of ASD diagnosis made by expert clinicians according to International Classification of Diseases (ICD)-10 criteria, informed by the Autism Diagnostic Observation Schedule-Generic (ADOS-G) and Autism Diagnostic Interview-Revised (ADI-R) assessments.

RESULTS

Of the participants, 73% received a clinical diagnosis of ASD. Self-report AQ scores did not significantly predict receipt of a diagnosis. While AQ scores provided high sensitivity of 0.77 [95% confidence interval (CI) 0.72-0.82] and positive predictive value of 0.76 (95% CI 0.70-0.80), the specificity of 0.29 (95% CI 0.20-0.38) and negative predictive value of 0.36 (95% CI 0.22-0.40) were low. Thus, 64% of those who scored below the AQ cut-off were 'false negatives' who did in fact have ASD. Co-morbidity data revealed that generalized anxiety disorder may 'mimic' ASD and inflate AQ scores, leading to false positives.

CONCLUSIONS

The AQ's utility for screening referrals was limited in this sample. Recommendations supporting the AQ's role in the assessment of adult ASD, e.g. UK NICE guidelines, may need to be reconsidered.

Effects of pulsatile electrical stimulation of the round window on central hyperactivity after cochlear trauma in guinea pig

Partial hearing loss induced by acoustic trauma has been shown in animal models to result in an increased spontaneous firing rate in central auditory structures. This so-called hyperactivity has been suggested to be involved in the generation of tinnitus, a phantom auditory sensation. Although there is no universal cure for tinnitus, electrical stimulation of the cochlea, as achieved by a cochlear implant, can result in significant reduction of the tinnitus percept. However, the mechanism by which this tinnitus suppression occurs is as yet unknown and furthermore cochlear implantation may not be an optimal treatment option for tinnitus sufferers who are not profoundly deaf. A better understanding of the mechanism of tinnitus suppression by electrical stimulation of the cochlea, may lead to the development of more specialised devices for those for whom a cochlear implant is not appropriate. This study aimed to investigate the effects of electrical stimulation in the form of brief biphasic shocks delivered to the round window of the cochlea on the spontaneous firing rates of hyperactive inferior colliculus neurons following acoustic trauma in guinea pigs. Effects during the stimulation itself included both inhibition and excitation but spontaneous firing was suppressed for up to hundreds of ms after the cessation of the shock train in all sampled hyperactive neurons. Pharmacological block of olivocochlear efferent action on outer hair cells did not eliminate the prolonged suppression observed in inferior colliculus neurons, and it is therefore likely that activation of the afferent pathways is responsible for the central effects observed.

Hyaluronic acid-coated poly(d,l-lactide) (PDLLA) nanofibers prepared by electrospinning and coating

Process of preparation of HA/PDLLA nanohybrids.

The effects of camicinal, a novel motilin agonist, on gastro-esophageal function in healthy humans-a randomized placebo controlled trial

BACKGROUND

A proportion of patients with foregut dysmotility fail to respond to standard interventions. Motilin agonists may be beneficial in this group. We aimed to determine the effect of camicinal, a novel motilin agonist, on gastrointestinal physiology in healthy volunteers.

METHODS

Healthy male subjects were randomly assigned to receive a single dose of 125 mg camicinal or placebo in a double-blind cross-over design. Esophageal function and reflux indices were assessed using high-resolution manometry (pre and 1.5-h post dose) and 24-h ambulatory multichannel intraluminal impedance/pH. After a standardized meal, subjects ingested a wireless motility capsule from which compartmental transit times and motility indices were derived. Subjects were restudied with the alternate intervention after 7 days.

KEY RESULTS

The study subjects (12 male, mean age 47.4 years, range 22-55) tolerated the drug well, except one who exhibited mild abdominal pain on both placebo and camicinal. In comparison to placebo, gastric emptying time (GET) was accelerated following camicinal (-115.4 min, 95% confidence interval -194.4, -36.4, p = 0.009). No effect was demonstrable on esophageal function, small bowel, colonic, or whole bowel transit times and motility indices. With camicinal, as part of a post hoc analysis, there was a trend association between the percentage reduction in GET and total number of acidic reflux events (r = 0.56, p = 0.09).

CONCLUSIONS & INFERENCES

Camicinal decreases GET and was generally well-tolerated. In health, the direct effects of camicinal are on accelerating GET with a potential secondary benefit of reducing reflux events, which warrant further exploration in patient cohorts.

Severing corneal nerves in one eye induces sympathetic loss of immune privilege and promotes rejection of future corneal allografts placed in either eye

Less than 10% of corneal allografts undergo rejection even though HLA matching is not performed. However, second corneal transplants experience a threefold increase in rejection, which is not due to prior sensitization to histocompatibility antigens shared by the first and second transplants since corneal grafts are selected at random without histocompatibility matching. Using a mouse model of penetrating keratoplasty, we found that 50% of the initial corneal transplants survived, yet 100% of the subsequent corneal allografts (unrelated to the first graft) placed in the opposite eye underwent rejection. The severing of corneal nerves that occurs during surgery induced substance P (SP) secretion in both eyes, which disabled T regulatory cells that are required for allograft survival. Administration of an SP antagonist restored immune privilege and promoted graft survival. Thus, corneal surgery produces a sympathetic response that permanently abolishes immune privilege of subsequent corneal allografts, even those placed in the opposite eye and expressing a completely different array of foreign histocompatibility antigens from the first corneal graft.

Suppression of putative tinnitus-related activity by extra-cochlear electrical stimulation

Studies on animals have shown that noise-induced hearing loss is followed by an increase of spontaneous firing at several stages of the central auditory system. This central hyperactivity has been suggested to underpin the perception of tinnitus. It was shown that decreasing cochlear activity can abolish the noise-induced central hyperactivity. This latter result further suggests that an approach consisting of reducing cochlear activity may provide a therapeutic avenue for tinnitus. In this context, extra-cochlear electric stimulation (ECES) may be a good candidate to modulate cochlear activity and suppress tinnitus. Indeed, it has been shown that a positive current applied at the round window reduces cochlear nerve activity and can suppress tinnitus reliably in tinnitus subjects. The present study investigates whether ECES with a positive current can abolish the noise-induced central hyperactivity, i.e., the putative tinnitus-related activity. Spontaneous and stimulus-evoked neural activity before, during and after ECES was assessed from single-unit recordings in the inferior colliculus of anesthetized guinea pigs. We found that ECES with positive current significantly decreases the spontaneous firing rate of neurons with high characteristic frequencies, whereas negative current produces the opposite effect. The effects of the ECES are absent or even reversed for neurons with low characteristic frequencies. Importantly, ECES with positive current had only a marginal effect on thresholds and tone-induced activity of collicular neurons, suggesting that the main action of positive current is to modulate the spontaneous firing. Overall, cochlear electrical stimulation may be a viable approach for suppressing some forms of (peripheral-dependent) tinnitus.