bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Energetics of Centrifugal Instability
Authors: Jiao Yang , Dewar W. K. 
Published: April 2015

AbstractIt has been shown recently that the California Undercurrent (CUC), and possibly poleward eastern boundary currents in general, generate mixing events through centrifugal instability (CI). Conditions favorable for CI are created by the strong horizontal shears developed in turbulent bottom layers of currents flowing in the direction of topographic waves. At points of abrupt topographic change, like promontories and capes, the coastal current separates from the boundary and injects gravitationally stable but dynamically unstable flow into the interior. The resulting finite-amplitude development of the instability involves overturnings and diabatic mixing. The purpose of this study is to examine the energetics of CI in order to characterize it as has been done for other instabilities and develop a framework in which to estimate its regional and global impacts. This study argues that CI is very efficient at mixing and possibly approaches what is thought to be the maximum efficiency for turbulent flows. The authors estimate that 10% of the initial energy in a CUC-like current is lost to either local mixing or the generation of unbalanced flows. The latter probably leads to nonlocal mixing. Thus, centrifugal instability is an effective process by which energy is lost from the balanced flow and spent in mixing neighboring water masses. The mixing is regionally important but of less global significance given its regional specificity.
Variogram-Based Proper Scoring Rules for Probabilistic Forecasts of Multivariate Quantities*
Authors: Scheuerer Michael , Hamill Thomas M. 
Published: April 2015

Abstract
Proper scoring rules provide a theoretically principled framework for the quantitative assessment of the predictive performance of probabilistic forecasts. While a wide selection of such scoring rules for univariate quantities exists, there are only few scoring rules for multivariate quantities, and many of them require that forecasts are given in the form of a probability density function. The energy score, a multivariate generalization of the continuous ranked probability score, is the only commonly used score that is applicable in the important case of ensemble forecasts, where the multivariate predictive distribution is represented by a finite sample. Unfortunately, its ability to detect incorrectly specified correlations between the components of the multivariate quantity is somewhat limited. In this paper the authors present an alternative class of proper scoring rules based on the geostatistical concept of variograms. The sensitivity of these variogram-based scoring rules to incorrectly predicted means, variances, and correlations is studied in a number of examples with simulated observations and forecasts; they are shown to be distinctly more discriminative with respect to the correlation structure. This conclusion is confirmed in a case study with postprocessed wind speed forecasts at five wind park locations in Colorado.
Sensitivity of Idealized Supercell Simulations to Horizontal Grid Spacing: Implications for Warn-on-Forecast
Authors: Potvin Corey K. , Flora Montgomery L. 
Published: April 2015

Abstract
The Warn-on-Forecast (WoF) program aims to deploy real-time, convection-allowing, ensemble data assimilation and prediction systems to improve short-term forecasts of tornadoes, flooding, lightning, damaging wind, and large hail. Until convection-resolving (horizontal grid spacing Δx &lt; 100 m) systems become available, however, resolution errors will limit the accuracy of ensemble model output. Improved understanding of grid spacing dependence of simulated convection is therefore needed to properly calibrate and interpret ensemble output, and to optimize trade-offs between model resolution and other computationally constrained parameters like ensemble size and forecast lead time.
Toward this end, the authors examine grid spacing sensitivities of simulated supercells over Δx of 333 m–4 km. Storm environment and physics parameterization are varied among the simulations. The results suggest that 4-km grid spacing is too coarse to reliably simulate supercells, occasionally leading to premature storm demise, whereas 3-km simulations more often capture operationally important features, including low-level rotation tracks. Further decreasing Δx to 1 km enables useful forecasts of rapid changes in low-level rotation intensity, though significant errors remain (e.g., in timing).
Grid spacing dependencies vary substantially among the experiments, suggesting that accurate calibration of ensemble output requires better understanding of how storm characteristics, environment, and parameterization schemes modulate grid spacing sensitivity. Much of the sensitivity arises from poorly resolving small-scale processes that impact larger (well resolved) scales. Repeating some of the 333-m simulations with coarsened initial conditions reveals that supercell forecasts can substantially benefit from reduced grid spacing even when limited observational density precludes finescale initialization.
Why do psychiatric patients have higher cancer mortality rates when cancer incidence is the same or lower?
Authors: Kisely Steve , Forsyth Simon , Lawrence David 
Published: April 2015

Objective: Studies of overall cancer incidence and mortality in psychiatric patients have had mixed results. Some have reported lower than expected cancer incidence or mortality, while others have found no association or an increased risk depending on sample, psychiatric diagnosis, cancer site and methodology. Few studies have compared cancer incidence and mortality using the same population and methodology. Method: A population-based record-linkage analysis to compare cancer incidence and mortality in psychiatric patients with that for the general Queensland population, using an historical cohort to calculate age- and sex-standardised rate ratios and hazard ratios. Mental health records were linked with cancer registrations and death records from 2002 to 2007. Results: There were 89,992 new cancer cases, of which 3349 occurred in people with mental illness. Cancer incidence was the same as the general population for most psychiatric disorders. Rates were actually lower for dementia (hazard ratio = 0.77; 95% confidence interval = [0.67, 0.88]) and schizophrenia (hazard ratio = 0.84; 95% confidence interval = [0.72, 0.98]). By contrast, mortality was increased in psychiatric patients (hazard ratio = 2.27; 95% confidence interval = [2.15, 2.39]) with elevated hazard ratios for all the main psychiatric diagnoses. Conclusions: Lifestyle, such as alcohol or tobacco use, would not explain our findings that people with mental illness are no more likely than the general population to develop cancer but more likely to die of it. Other factors may be the difficulty in differentiating medically explained and unexplained symptoms, greater case fatality or inequity in access to specialist procedures. The study highlights the need for improved cancer screening, detection and intervention in this population.
An Investigation of Operational Decision Making in Situ
Authors: Cohen-Hatton Sabrina R. , Butler Philip C. , Honey Robert C. 
Published: April 2015

Objective The aim of this study was to better understand the nature of decision making at operational incidents in order to inform operational guidance and training. Background Normative models of decision making have been adopted in the guidance and training for emergency services. In these models, it is assumed that decision makers assess the current situation, formulate plans, and then execute the plans. However, our understanding of how decision making unfolds at operational incidents remains limited. Method Incident commanders, attending 33 incidents across six U.K. Fire and Rescue Services, were fitted with helmet-mounted cameras, and the resulting video footage was later independently coded and used to prompt participants to provide a running commentary concerning their decisions. Results The analysis revealed that assessment of the operational situation was most often followed by plan execution rather than plan formulation, and there was little evidence of prospection about the potential consequences of actions. This pattern of results was consistent across different types of incident, characterized by level of risk and time pressure, but was affected by the operational experience of the participants. Conclusion Decision making did not follow the sequence of phases assumed by normative models and conveyed in current operational guidance but instead was influenced by both reflective and reflexive processes. Application These results have clear implications for understanding operational decision making as it occurs in situ and suggest a need for future guidance and training to acknowledge the role of reflexive processes.
Transaxillary Thyroidectomies
Authors: Kiong Kimberley Liqin , Iyer N. Gopalakrishna , Skanthakumar Thakshayeni , Ng Jeremy Chung Fai , Tan Ngian Chye , Tay Hin Ngan , Tan Hiang Khoon 
Published: April 2015

ObjectiveRobotic and endoscopic approaches have become more accepted in thyroid surgery, with current literature documenting the experience of high‐volume centers. We adopted both approaches concurrently, and this series presents our initial experience to assess the more practical option for low‐ to moderate‐volume centers starting out with transaxillary thyroidectomies.Study DesignCase series with chart review.SettingTertiary academic center.Subjects and MethodsOver a period of 4 years, 101 patients underwent transaxillary thyroidectomies, of whom 48 underwent robotic thyroidectomy and 53 underwent endoscopic thyroidectomy. Data analysis includes patient characteristics, procedure time, thyroid pathology, and postoperative complications. A survey was conducted among surgeons to assess the subjective experience.ResultsEndoscopic hemithyroidectomies had a significantly shorter duration of operation (145.8 minutes) vs that of robotic hemithyroidectomies (193.6 minutes), P <. 001. The mean time taken for the first 5 hemithyroidectomies vs the last 5 hemithyroidectomies showed a greater drop in the endoscopic group (49.1%) vs the robotic group (18.6%). There were 2 cases of transient recurrent laryngeal nerve injury. In the surgeon survey, the endoscopic technique was perceived to have less need for peripheral support, while the robotic technique was preferred for its shorter learning curve.ConclusionIn terms of outcome, both techniques are comparable at least in the initial phase. Based on our early experience, the endoscopic technique may be less intuitive with a longer learning curve, although at steady state, it may be the quicker procedure. This is relevant for low‐ to moderate‐volume centers starting their transaxillary thyroidectomy program.
A Swallow Preservation Protocol Improves Function for Veterans Receiving Chemoradiation for Head and Neck Cancer
Authors: Peng Kevin A. , Kuan Edward C. , Unger Lindsey , Lorentz William C. , Wang Marilene B. , Long Jennifer L. 
Published: April 2015

ObjectiveDetermine the efficacy of a swallow preservation protocol (SPP) on maintaining swallow function in patients undergoing chemoradiation (CRT) or radiation therapy alone (RT) for head and neck squamous cell carcinoma (HNSCC).Study designRetrospective case series.SettingVeterans Affairs medical center.Subjects and MethodsPatients treated with CRT or RT for HNSCC between February 2006 and November 2013 were studied. Those enrolled in the SPP participated in swallowing, jaw, and tongue exercises during cancer therapy. The comparator group received no swallowing intervention during CRT. A previously described functional outcome swallowing scale (FOSS; 0 = no symptoms and 5 = nonoral feeding for all nutrition) was used to quantify dysphagia prior to and at the completion of cancer therapy, and an analysis was performed to compare swallowing function.ResultsForty‐one (all male; mean age, 66 years) and 66 patients (all male; mean age, 61 years) were included in the SPP and comparator groups, respectively. In the SPP group, mean pre‐ and posttreatment FOSS scores were 2.2 and 2.2, respectively, while the corresponding scores in the comparator group were 1.8 and 2.7, respectively, with posttreatment FOSS scores being significantly worse than pretreatment FOSS scores in the comparator group only.ConclusionPatients enrolled in the SPP demonstrated preserved swallowing function over the course of cancer treatment compared with a comparator group. This confirms the importance of early evaluation and intervention for dysphagia prior to and during CRT or RT alone.
Characterization of Vestibulopathy in Individuals with Type 2 Diabetes Mellitus
Authors: Ward Bryan K. , Wenzel Angela , Kalyani Rita R. , Agrawal Yuri , Feng Allen L. , Polydefkis Michael , Ying Howard S. , Schubert Michael C. , Zuniga M. Geraldine , Della Santina Charles C. , Carey John P. 
Published: April 2015

ObjectivePrevious observational studies suggest higher rates of vestibular dysfunction among patients with type 2 diabetes mellitus (DM) compared with those without diabetes. This study aims to functionally localize vestibular dysfunction in adults with type 2 DM.Study DesignProspective cohort study.SettingTertiary academic medical center.Subjects and MethodsAdults 50 years of age and older with ≥10‐year history of type 2 DM were recruited (December 2011–February 2013, n = 25). Vestibular function was assessed by cervical and ocular vestibular‐evoked myogenic potentials (VEMPs), testing the saccule and utricle, respectively. Head thrust dynamic visual acuity testing assessed semicircular canal (SCC) function in all canal planes. Results were compared with nondiabetic age‐matched controls (n = 25).ResultsSubjects were 64.7 ± 7.6 years old, were 40% female, and had a mean hemoglobin A1c of 8.3% ± 1.7%. SCC dysfunction was more common than otoconial organ dysfunction, with 70% of subjects with DM demonstrating impaired performance of at least 1 SCC (ΔlogMAR ≥0.18) and 50% demonstrating otoconial organ impairment (absent ocular VEMP and/or cervical VEMP). Adults with type 2 DM had poorer lateral and superior SCC performance (P <. 05) but similar posterior SCC performance compared with controls (P =. 16). Both cervical VEMP peak‐to‐peak amplitude and ocular VEMP n1 amplitude were also decreased with diabetes (P <. 01).ConclusionAdults with type 2 DM have poorer performance on tests of vestibular function related to both SCC and otoconial organ function compared with nondiabetic age‐matched adults. Future studies are needed to better understand the relationship between vestibular function and functional disability in persons with diabetes.
Is Stroke Early Supported Discharge still effective in practice? A prospective comparative study
Authors: Fisher Rebecca J , Cobley Christine S , Potgieter Iskra , Moody Amy , Nouri Fiona , Gaynor Catherine , Byrne Adrian , Walker Marion F 
Published: April 2015

Objective: Randomised controlled trials have shown the benefits of Early Supported Discharge (ESD) of stroke survivors. Our aim was to evaluate whether ESD is still beneficial when operating in the complex context of frontline healthcare provision. Design: We conducted a cohort study with quasi experimental design. A total of 293 stroke survivors (transfer independently or with assistance of one, identified rehabilitation goals) within two naturally formed groups were recruited from two acute stroke units: ‘ESD’ n=135 and ‘Non ESD’ n=158 and 84 caregivers. The ‘ESD’ group accessed either of two ESD services operating in Nottinghamshire, UK. The ‘Non ESD’ group experienced standard practices for discharge and onward referral. Outcome measures (primary: Barthel Index) were administered at baseline, 6 weeks, 6 months and 12 months. Results: The ESD group had a significantly shorter length of hospital stay ( P=0.029) and reported significantly higher levels of satisfaction with services received ( P<0.001). Following adjustment for age differences at baseline, participants in the ESD group ( n=71) had significantly higher odds (compared to the Non ESD group, n=85) of being in the ⩾90 Barthel Index category at 6 weeks (OR = 1.557, 95% CI 2.579 to 8.733), 6 months (OR = 1.541, 95% CI 2.617 to 8.340) and 12 months (OR 0.837, 95% CI 1.306 to 4.087) respectively in relation to baseline. Carers of patients accessing ESD services showed significant improvement in mental health scores ( P<0.01). Conclusion: The health benefits of ESD are still evident when evidence based models of these services are implemented in practice.
Burnout, psychological morbidity and use of coping mechanisms among palliative care practitioners: A multi-centre cross-sectional study
Authors: Koh Mervyn Yong Hwang , Chong Poh Heng , Neo Patricia Soek Hui , Ong Yew Jin , Yong Woon Chai , Ong Wah Ying , Shen Mira Li Juan , Hum Allyn Yin Mei 
Published: April 2015

Background: The prevalence of burnout, psychological morbidity and the use of coping mechanisms among palliative care practitioners in Singapore have not been studied. Aim: We aimed to study the prevalence of burnout and psychological morbidity among palliative care practitioners in Singapore and its associations with demographic and workplace factors as well as the use of coping mechanisms. Design: This was a multi-centre, cross-sectional study of all the palliative care providers within the public healthcare sector in Singapore. Setting/participants: The study was conducted in hospital palliative care services, home hospice and inpatient hospices in Singapore. The participants were doctors, nurses and social workers. Results: The prevalence of burnout among respondents in our study was 91 of 273 (33.3%) and psychological morbidity was 77 (28.2%). Working >60 h per week was significantly associated with burnout (odds ratio: 9.02, 95% confidence interval: 2.3–35.8, p = 0.002) and psychological morbidity (odds ratio: 7.21, 95% confidence interval: 1.8–28.8, p = 0.005). Home hospice care practitioners (41.5%) were more at risk of developing psychological morbidity compared to hospital-based palliative care (17.5%) or hospice inpatient care (26.0%) ( p = 0.007). Coping mechanisms like physical well-being, clinical variety, setting boundaries, transcendental (meditation and quiet reflection), passion for one’s work, realistic expectations, remembering patients and organisational activities were associated with less burnout. Conclusion: Our results reveal that burnout and psychological morbidity are significant in the palliative care community and demonstrate a need to look at managing long working hours and promoting the use of coping mechanisms to reduce burnout and psychological morbidity.
80-kVp CT angiography for endovascular aneurysm repair follow-up with halved contrast medium dose and preserved diagnostic quality
Authors: Lehti Leena , Nyman Ulf , Söderberg Marcus , Björses Katarina , Gottsäter Anders , Wassélius Johan 
Published: April 2015

Background Follow-up of endovascular aneurysm repair (EVAR) with life-long computed tomography angiography (CTA) surveillance exposes patients with impaired renal function to repeated risks of contrast medium-induced nephropathy (CIN). Purpose To retrospectively compare vascular attenuation, image noise, contrast-to-noise ratio (CNR), subjective image quality and effective radiation dose (mSv) for CTA with a 16-multirow detector CT (MDCT) equipment at 80 kVp after EVAR using a contrast medium (CM) dose that is half of that used at 120 kVp. Material and Methods Forty patients with estimated glomerular filtration rate (eGFR) <45 mL/min underwent 80-kVp CTA with 160 mg I/kg, and 40 patients with eGFR ≥45 mL/min 120-kVp CTA with 320 mg I/kg (maximum dose weight, 80 kg). Arterial phase analysis included vascular attenuation, image noise and CNR, and calculated effective dose. Subjective image quality was assessed on a 4-point scale by two blinded readers at three different levels as well as overall. Results Median values in the 80/120 kVp cohorts were: age, 74–75 years; body weight, 77/80 kg; BMI 24/27 kg/m2; CM dose, 13/25 gram-iodine; gram-iodine/GFR ratio, 0.35/0.38; mean aortic attenuation, 313/326 HU; image noise, 26/32 HU; CNR 10–11; subjective image quality score, 3.0–3.5 (Reader 1) and 3.0–3.3 (Reader 2); number of non-diagnostic examinations, 0/1; and effective dose, 4.5/5.1 mSv. There was no statistically significant difference in aortic CNR and effective dose between the 80 and 120 kVp cohorts. Conclusion 80 kVp 16-MDCT with halved CM dose tailored to body weight for CTA follow-up of EVAR may provide satisfactory diagnostic results compared to common standards and be beneficial for patients at risk of CIN, though the present CT equipment may limit the use of the method to patients below 90 kg or with a BMI below 35 kg/m2.
Changes in Involved and Uninvolved Limb Function During Rehabilitation After Anterior Cruciate Ligament Reconstruction
Authors: Rohman Eric , Steubs J. Tyler , Tompkins Marc 
Published: April 2015

Background: Functional testing is used to assess anterior cruciate ligament (ACL) reconstruction rehabilitation, with the goal of symmetric ability. The pattern of change in the uninvolved limb’s function during rehabilitation is not established. Hypotheses: (1) Involved and uninvolved limb ability increases during rehabilitation, but the uninvolved limb ability increases to a lesser degree. (2) Hop tests will show larger initial asymmetry and will improve the most with rehabilitation. Study Design: Cohort study; Level of evidence, 3. Methods: This was a retrospective case series of 122 patients who underwent ACL reconstruction at our ambulatory surgery center and received multiple postoperative Standard Functional Tests (SFTs) between October 2009 and October 2013. Ten of the 12 individual tests within the SFT battery were analyzed. The patients’ earliest and latest SFTs were compared for changes in Limb Symmetry Index (LSI) and absolute function in each limb. We also analyzed the subgroup with SFTs (n = 38) at both 4 and 6 months postoperatively. Results: In all patients with multiple SFTs, involved limb performance increased in all tests except eyes-closed stork. Uninvolved limb performance increased in 4 SFT component tests and decreased in none. LSI significantly improved in 6 tests, all of which also showed involved limb improvement that was significant. Of these 6 tests, 5 showed initial LSI below 90%: single-leg squat, retro step-up, single-leg hop, crossover triple hop, and timed hop. Retro step-up and single-leg hop showed LSI improvements greater than 10 percentage points. In patients with 4- and 6-month data, involved limb performance increased in all tests except single-leg triple hop. Uninvolved limb performance increased in 5 SFT component tests and decreased in none. LSI significantly improved in 4 tests, all of which had initial LSI below 90%, and showed involved limb improvement that was significant. Retro step-up, single-leg hop, and crossover triple hop showed LSI improvements greater than 10 percentage points. Conclusion: During ACL reconstruction rehabilitation, LSI improvements indicated absolute increases in involved limb ability and were not attributable to uninvolved limb deterioration. The single-leg squat, retro step-up, single-leg hop, crossover triple hop, and timed hop are suggested as highly useful tests, since all showed initial LSI below 90%, with significant LSI improvement after rehabilitation.