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For any appreciable radiation source, such as a nuclear reactor core or radiation physics accelerator, there will be the safety requirement to shield operators from the effects of the radiation from the source. Both the size and weight of the shield need to be minimised to reduce costs (and to increase the space available for the maintenance envelope on a plant). This needs to be balanced against legal radiation dose safety limits and the requirement to reduce the dose to operators As Low As Reasonably Practicable (ALARP). This paper describes a method that can be used, early in a shield design, to scope the design and provide a practical estimation of the size of the shield by optimising the shield internals. In particular, a theoretical model representative of a small reactor is used to demonstrate that the primary shielding radius, thickness of the primary shielding inner wall and the thicknesses of two steel inner walls, can be set using the Lagrange multiplier method with a constraint on the total flux on the outside of the shielding. The results from the optimisation are presented and an RZ finite element transport theory calculation is used to demonstrate that, using the optimised geometry, the constraint is achieved.

Abstract Background Heavy menstrual bleeding is a common symptom amongst women of reproductive age, yet questions remain about why some women experience this as a problem while others do not. We investigated the concerns of women who reported heavy menstrual bleeding on questionnaire. Methods A cross-sectional postal survey and qualitative interviews were carried out amongst a community-based sample of women in Lothian, Scotland. 906 women aged 25 to 44 reported heavy or very heavy periods in response to a postal survey of 2833 women registered with 19 general practices. Amongst those who had reported heavy menstrual bleeding, analysis was carried out of responses to the free text questionnaire item, "What bothers you most about your periods?" In addition, 32 of these women participated in qualitative interviews and their accounts were analysed to explore how menstrual symptoms and 'problems' with periods were experienced. Results Even amongst this subgroup of women, selected on the basis of having reported their periods as heavy in the survey, pain was the aspect of their periods that 'most bothered' them, followed by heaviness, mood changes or tiredness, and irregularity or other issues of timing. Interviewees' accounts similarly suggested that a range of menstrual symptoms were problematic and some women did not disentangle which was worst. Judgements of periods as a problem were based on the impact of menstrual symptoms on daily life and this was contingent on social circumstances such as type of paid work and other responsibilities. Although women spoke readily of whether their periods were a problem, there was less clarity in accounts of whether or not menstrual loss was 'heavy'; women said they made judgements based on what was normal for them, degree of difficulty in containing blood loss and pattern of loss. Conclusion Women with heavy periods are bothered by a range of menstrual symptoms and their impact on everyday life. Clinical emphasis should be on clarifying the presenting problem and providing help and advice for this, as well as on excluding serious disease. Sometimes simple approaches, such as help with analgesia, may be all that is required.

Study Objective: The primary objective of this retrospective safety study was to determine the incidence of torsades de pointes (TdP) or death following perioperative administration of low-dose, 4 mg, ondansetron for postoperative nausea and vomiting., Design and Setting: This is a single-center retrospective clinical trial., Patients: The authors identified 32,737 patients who received 37,589 doses of ondansetron during a 2-year time frame between March 2009 and February 2011 for surgical nausea prophylaxis or treatment of nausea., Measurements and Main Results: Patients were cross-matched with an electrocardiogram and adverse outcome database; this identified 4759 patients with documentation of a QTc >450 milliseconds (ms), all ventricular tachycardias including TdP within 48 hours of receiving ondansetron, or death within 7 days of receiving ondansetron. No patients developed TdP or died as a direct result of ondansetron administration (n = 0; event rate = 0.0 per 10,000, 95% CI 0.0 to 1.1 per 10,000). Forty-six of 32,737 surgical patients had documented monomorphic ventricular tachycardia (VT) (n = 14; event rate = 4.3 per 10,000, 95% CI 2.3 to 7.2 per 10,000) or died (n = 32; event rate = 9.8 per 10,000, 95% CI 6.7 to 13.8 per 10,000) within 48 h of ondansetron administration. All monomorphic VT episodes were precipitated by existing cardiovascular disease; and 7 of 14 patients had documented monomorphic VT prior to receiving ondansetron. Of the 32 surgical patients who died, all deaths were precipitated by pre-existing disease., Conclusion: No episodes of TdP were identified in patients receiving ondansetron perioperatively. This suggests that low-dose ondansetron does not contribute to the development of TdP., (© 2022 Pharmacotherapy Publications, Inc.)

Background: Dyad learning has been shown to be an effective tool for teaching procedural skills, but little is known about how dyad learning may impact the stress, anxiety, and cognitive load that a student experiences when learning in this manner. In this pilot study, we investigate the relationship between dyad training on stress, anxiety, cognitive load, and performance in a simulated bradycardia scenario., Methods: Forty-one fourth-year medical school trainees were randomized as dyads (n = 24) or individuals (n = 17) for an education session on day 1. Reassessment occurred on day 4 and was completed as individuals for all trainees. Primary outcomes were cognitive load (Paas scale), stress (Cognitive Appraisal Ratio), and anxiety levels (abbreviated State-Trait Anxiety Inventory). Secondary outcomes were time-based performance metrics., Results: On day 1 we observed significant differences for change in anxiety and stress measured before and after the training scenario between groups. Individuals compared to dyads had larger mean increases in anxiety, (19.6 versus 7.6 on 80-point scale, p = 0.02) and stress ratio (1.8 versus 0.9, p = 0.045). On the day 4 post-intervention assessment, no significant differences were observed between groups. Secondary outcomes were significant for shorter time to diagnosis of bradycardia (p = 0.01) and time to initiation of pacing (p = 0.04) in the dyad group on day 1. On day 4, only time to recognizing the indication for pacing was significantly shorter for individual training (hazard ratio [HR] = 2.26, p = 0.02)., Conclusions: Dyad training results in lower stress and anxiety levels with similar performance compared to individual training.

Background: Cricothyrotomy is a final recourse for salvaging a difficult airway, yet most anesthesiology providers have little training, exposure, or comfort with the procedure. Pig tracheas are frequently used for training, but are single use and require special handling and storage. Other simulation models, such as mannequins and cadavers, are costly. Advances in 3dimensional (3D) printing have improved accessibility and decreased costs. This research project sought to determine whether an inexpensive 3D-printed task trainer was noninferior to pig tracheas for teaching surgical cricothyrotomy skills., Methods: Anesthesiology residents were enrolled in an institutional review board-exempted, unblinded, randomized, controlled, single-institution, noninferiority trial. Participants were trained in the scalpel-finger-bougie technique for surgical cricothyrotomy. Participants were randomized to practice 5 repetitions on either a pig trachea or the 3D model and were assessed on time to cricothyrotomy completion on a pig trachea before and after practice., Results: Demographic characteristics of the 25 workshop attendees were similar between study arms. Overall mean (SD) improvement in speed was 9 (12) seconds ( P = .001). Postpractice times were similar between groups (analysis of covariance estimated difference of -0.1 seconds [95% confidence interval, -9.4 to 9.2]; P = .55). The 3D model was noninferior to the pig trachea at the prespecified noninferiority margin of 10 seconds ( P = .017)., Conclusions: The 3D model was noninferior to pig tracheas for improving the time to completion of a surgical cricothyrotomy. A 3D-printed model offers a viable alternative to pig tracheas for emergency airway simulation that is inexpensive, reusable, and readily modified to simulate challenging airway anatomy., Competing Interests: Disclosures: The authors declare no conflicts of interest. Mayo Clinic does not endorse specific products or services included in this article., (© 2021 Society for Education in Anesthesia.)

In this case, a 79-year-old male presented with new anteroseptal Q waves and T-wave inversions across the precordial leads following an otherwise uneventful endovascular repair of his thoracoabdominal aortic aneurysm. The patient had no history of cardiac disease and had undergone a dobutamine stress echocardiogram within the preceding 6 months that showed no evidence of inducible ischemia. Nevertheless, routine postoperative electrocardiogram (EKG) revealed new Q waves and T-wave inversions and transthoracic echocardiogram that demonstrated akinesis of the left ventricle (LV) apex with chronic-appearing apical thrombus. We will further discuss preoperative evaluation of cardiovascular risk along with postoperative interpretation of EKG abnormalities.

Perioperative serotonin syndrome has been associated with a number of medications and herbal supplements. We report a patient who developed serotonin syndrome immediately after an endoscopic procedure in which the preoperative use of black seed oil appears to have played a role in stimulating the syndrome. Black seed oil has not been previously reported in association with perioperative serotonin syndrome. Anesthesia professionals should be aware that patients taking black seed oil supplements may develop serotonin syndrome postoperatively.

Determining the extent to which Symbiodinium communities in corals are inherited versus environmentally acquired is fundamental to understanding coral resilience and to predicting coral responses to stressors like warming oceans that disrupt this critical endosymbiosis. We examined the fidelity with which Symbiodinium communities in the brooding coral Seriatopora hystrix are vertically transmitted and the extent to which communities are genetically regulated, by genotyping the symbiont communities within 60 larvae and their parents (9 maternal and 45 paternal colonies) using high-throughput sequencing of the ITS2 locus. Unexpectedly, Symbiodinium communities associated with brooded larvae were distinct from those within parent colonies, including the presence of types not detected in adults. Bayesian heritability (h 2 ) analysis revealed that 33% of variability in larval Symbiodinium communities was genetically controlled. Results highlight flexibility in the establishment of larval symbiont communities and demonstrate that symbiont transmission is not exclusively vertical in brooding corals. Instead, we show that Symbiodinium transmission in S. hystrix involves a mixed-mode strategy, similar to many terrestrial invertebrate symbioses. Also, variation in the abundances of common Symbiodinium types among adult corals suggests that microhabitat differences influence the structure of in hospite Symbiodinium communities. Partial genetic regulation coupled with flexibility in the environmentally acquired component of Symbiodinium communities implies that corals with vertical transmission, like S. hystrix, may be more resilient to environmental change than previously thought.

Epicardial pacing wires are routinely used to avoid hemodynamic instability due to perioperative arrhythmias after cardiac surgery. In rare cases, pacing wires themselves can be associated with potentially life-threatening complications. Herein, we present a novel case of hemorrhagic shock and hemoperitoneum after temporary epicardial pacing wire removal.

Repeated ingestion of small objects has been previously reported in the psychiatric literature. We recently had a patient with repeated intentional foreign body ingestion syndrome who developed complete airway obstruction and cardiac arrest after ingesting a computer mouse tracking ball. We use our case to suggest a pathway that can be used for similar emergent airway problems.

Within populations of brooding sessile corals, sperm dispersal constitutes the mechanism by which gametes interact and mating occurs, and forms the first link in the network of processes that determine specieswide connectivity patterns. However, almost nothing is known about sperm dispersal for any internally fertilizing coral. In this study, we conducted a parentage analysis on coral larvae collected from an area of mapped colonies, to measure the distance sperm disperses for the first time in a reef-building coral and estimated the mating system characteristics of a recently identified putative cryptic species within the Seriatopora hystrix complex (ShA; Warner et al. 2015). We defined consensus criteria among several replicated methods (COLONY 2.0, CERVUS 3.0, MLTR v3.2) to maximize accuracy in paternity assignments. Thirteen progeny arrays indicated that this putative species produces exclusively sexually derived, primarily outcrossed larvae (mean t(m) = 0.999) in multiple paternity broods (mean r(p) = 0.119). Self-fertilization was directly detected at low frequency for all broods combined (2.8%), but comprised 23% of matings in one brood. Although over 82% of mating occurred between colonies within 10 m of each other (mean sperm dispersal = 5.5 m ± 4.37 SD), we found no evidence of inbreeding in the established population. Restricted dispersal of sperm compared to slightly greater larval dispersal appears to limit inbreeding among close relatives in this cryptic species. Our findings establish a good basis for further work on sperm dispersal in brooding corals and provide the first information about the mating system of a newly identified and abundant cryptic species., (© 2016 John Wiley & Sons Ltd.)

Mounting evidence of cryptic species in a wide range of taxa highlights the need for careful analyses of population genetic data sets to unravel within-species diversity from potential interspecies relationships. Here, we use microsatellite loci and hierarchical clustering analysis to investigate cryptic diversity in sympatric and allopatric (separated by 450 km) populations of the widespread coral Seriatopora hystrix on the Great Barrier Reef. Structure analyses delimited unique genetic clusters that were confirmed by phylogenetic and extensive population-level analyses. Each of four sympatric yet distinct genetic clusters detected within S. hystrix demonstrated greater genetic cohesion across regional scales than between genetic clusters within regions (<10 km). Moreover, the magnitude of genetic differentiation between different clusters (>0.620 G"ST ) was similar to the difference between S. hystrix clusters and the congener S. caliendrum (mean G"ST 0.720). Multiple lines of evidence, including differences in habitat specificity, mitochondrial identity, Symbiodinium associations and morphology, corroborate the nuclear genetic evidence that these distinct clusters constitute different species. Hierarchical clustering analysis combined with more traditional population genetic methods provides a powerful approach for delimiting species and should be regularly applied to ensure that ecological and evolutionary patterns interpreted for single species are not confounded by the presence of cryptic species., (© 2015 John Wiley & Sons Ltd.)

This paper assesses the quality and cost of a pregnancy care program based on explicit and achieved patient competencies. By using the USPHS Content of Prenatal Care (1989), key psychosocial/education elements of perinatal care were identified. The goal was a process of patient education that is competency based, integrated, and outcome oriented. Psychosocial assessment, patient education tools, criterion-based length of postpartum stay, and home nursing follow-up were implemented as part of a Comprehensive Pregnancy Program (CPP). Case-control and cohort survey methodology were used to evaluate outcome. There was a significant decrease in hospital length of stay for mothers and newborns after implementation of the CPP. Post-discharge maternal emergency room visits and/or readmits did not increase. Differences in newborn emergency room visits and/or readmits were non-significant. There was a marked reduction in hospital costs for mothers and newborns. Patient satisfaction remained high. Core competencies forming the basis of educational and assessment programs allow the focus of care to be optimal outcome, and provide a useful template against which to measure prenatal, intrapartum, and postpartum care.

Staff members from the University of Michigan Medical Center (UMMC), 1990 winner of the Commitment to Quality Award, describe how they integrated its quality assurance (QA) program into its total quality management (TQM) strategy. The QA program has changed in recent years to establish quality as a central priority, to educate staff in the importance of quality, and to disseminate information more effectively. While these initiatives were underway, UMMC began to embrace TQM as an operating philosophy. Recognizing both the strengths and weaknesses of QA, staff members have worked to apply TQM principles (eg, focus on processes) to QA while using the ongoing monitoring of QA to identify opportunities for improvement within the organization's TQM management system.