Occam's razor on the mechanism of resistive-wall-mode-induced ß limits in diverted tokamaks.

External kink modes, believed to be the drive of the ß-limiting resistive wall mode, are strongly stabilized by the presence of a separatrix. We thus propose a novel mechanism explaining the appearance of long-wavelength global instabilities in free boundary high-ß diverted tokamaks, retrieving the experimental observables within a physical framework dramatically simpler than most of the models employed for the description of such phenomena. It is shown that the magnetohydrodynamic stability is worsened by the synergy of ß and plasma resistivity, with wall effects significantly screened in an ideal, i.e., with vanishing resistivity, plasma with separatrix. Stability can be improved by toroidal flows, depending on the proximity to the resistive marginal boundary. The analysis is performed in tokamak toroidal geometry, and includes averaged curvature and essential separatrix effects.

Quantifying Distances Between Non-Elliptical Clusters to Enhance the Identification of Meaningful Emotional Reactivity Subtypes.

Coordinated emotional responses across psychophysiological and subjective indices is a cornerstone of adaptive emotional functioning. Using clustering to identify cross-diagnostic subgroups with similar emotion response profiles may suggest novel underlying mechanisms and treatments.However, many psychophysiological measures are non-normal even in homogenous samples, and over-reliance on traditional elliptical clustering approaches may inhibit the identification of meaningful subgroups. Finite mixture models that allow for non-elliptical cluster distributions is an emerging methodological field that may overcome this hurdle. Furthermore, succinctly quantifying pairwise cluster separation could enhance the clinical utility of the clustering solutions. However, a comprehensive examination of distance measures in the context of elliptical and non-elliptical model-based clustering is needed to provide practical guidance on the computation, benefits, and disadvantages of existing measures. We summarize several measures that can quantify the multivariate distance between two clusters and suggest practical computational tools. Through a simulation study, we evaluate the measures across three scenarios that allow for clusters to differ in location, scale, skewness, and rotation. We then demonstrate our approaches using psychophysiological and subjective responses to emotional imagery captured through the Transdiagnostic Anxiety Study. Finally, we synthesize findings to provide guidance on how to use distance measures in clustering applications.

Implementation of Postoperative Standard Opioid Prescribing Schedules Reduces Opioid Prescriptions Without Change in Patient-reported Pain Outcomes.

OBJECTIVE: To implement Standard Opioid Prescribing Schedules (SOPS) based on opioid use following urologic surgeries and to evaluate how evidence-based prescribing schedules affect opioid use and patient reported outcomes. METHODS: Patients who underwent urologic surgeries within 6 procedure subtypes at UNC Health during the 2 study time periods ("pre-SOPS": 7/2017-1/2018, "post-SOPS": 7/2018-1/2019) were invited to complete a survey analyzing postoperative opioid usage, storage and disposal, and patient reported outcomes (including pain interference using a validated questionnaire). A pharmacy database provided medication prescribing data and patient demographics. During the pre-SOPS time period, baseline outcomes were measured. Following the pre-SOPS period, usage amounts were analyzed and Standard Opioid Prescribing Schedules were developed to guide prescriptions during the post-SOPS period. Descriptive summary statistics and appropriate t test or r2 were calculated. RESULTS: A total of 438 patients within 6 procedure types completed the survey (pre-SOPS: 282 patients, post-SOPS: 156 patients). Pre-SOPS, patients were prescribed significantly more 5-mg oxycodone tablets than used (20.9 vs 7.8, P <.001). Post-SOPS, compared to pre-SOPS amounts, patients were prescribed significantly fewer tablets (12.7 vs 20.9, P <.001) and used fewer tablets (5.3 vs 7.8, P = .003). No difference was observed in pain interference (average t-score (standard deviation): 54.33 (10.9) pre-SOPS vs 55.89 (9.1) post-SOPS, P = .125) or patient satisfaction (95% pre-SOPS vs 94% post-SOPS). CONCLUSION: Adherence to data-driven postoperative opioid prescribing schedules reduce opioid prescriptions and use without compromising pain interference or patient satisfaction. These results have important implications for urologists' ability to decrease opioid prescriptions and fight the opioid epidemic.

Identification of an Optimized Heating and Fast Ion Generation Scheme for the Wendelstein 7-X Stellarator.

A Doppler shifted resonance minority species ion cyclotron range of frequency (ICRF) scheme for heating neutral beam ions has been identified and optimized for the Wendelstein 7-X stellarator. Compared with more conventional methods, the synergetic scheme increases the normalized core collisional power transfer to the background plasma, and induces larger concentrations of energetic ions. Simulations in the intricate 3D magnetic stellarator geometry reveal an energetic distribution function that is only weakly anisotropic, and is thus relevant to fast ion and alpha particle driven Alfvén eigenmode experimental preparation. Quasilinear theory and simulations of the Joint European Torus indicate that the excellent confinement properties are due to increased velocity diffusion from ICRF interaction along the magnetic field lines. Agreement is found between SCENIC simulations and Joint European Torus experimental measurements for the total neutron rate and the energy distribution of the fast ions.

Annotated normal CT data of the abdomen for deep learning: Challenges and strategies for implementation.

PURPOSE: The purpose of this study was to report procedures developed to annotate abdominal computed tomography (CT) images from subjects without pancreatic disease that will be used as the input for deep convolutional neural networks (DNN) for development of deep learning algorithms for automatic recognition of a normal pancreas. MATERIALS AND METHODS: Dual-phase contrast-enhanced volumetric CT acquired from 2005 to 2009 from potential kidney donors were retrospectively assessed. Four trained human annotators manually and sequentially annotated 22 structures in each datasets, then expert radiologists confirmed the annotation. For efficient annotation and data management, a commercial software package that supports three-dimensional segmentation was used. RESULTS: A total of 1150 dual-phase CT datasets from 575 subjects were annotated. There were 229 men and 346 women (mean age: 45±12years; range: 18-79years). The mean intra-observer intra-subject dual-phase CT volume difference of all annotated structures was 4.27mL (7.65%). The deep network prediction for multi-organ segmentation showed high fidelity with 89.4% and 1.29mm in terms of mean Dice similarity coefficients and mean surface distances, respectively. CONCLUSIONS: A reliable data collection/annotation process for abdominal structures was developed. This process can be used to generate large datasets appropriate for deep learning.

Ultrasonic preparation, stability and thermal conductivity of a capped copper-methanol nanofluid.

This paper describes a two-step method to prepare novel copper-methanol nanofluids capped with a short chain molecule, (3-Aminopropyl)trimethoxysilane (APTMS). Two commercial nanopowders were dispersed at various powers using a 20 kHz ultrasonic probe into solutions of methanol and the capping agent. Ultrasonic energy input was measured by calorimetry with z-average diameters, intensity and number size distributions recorded by a dynamic light scattering technique. The stability of the dispersion was monitored visually, and quantified by recording the zeta potential. Dispersions of the bare powder were used as a control. Absorption spectroscopy was used to confirm the presence of the capping agent. The thermal conductivities of 0 to 10% wt./vol. (1.1% vol.) dispersions of the capped copper-methanol nanofluid were determined using a C-Therm analyzer. Optimum ultrasonic de-agglomeration conditions gave dispersions with a z-average particle size of <200 nm and a PdI of <0.2. The capped particles showed good stability; up to six months in some instances, and an average zeta potential of +38 mV was recorded. The thermal conductivity of the nanofluid increased with concentration, and an enhancement of 9% over the base fluid was found at 10% wt./vol. (1.1% vol.). This innovative work has demonstrated the ultrasonic preparation and stability of copper nanoparticles protected with APTMS; a short chain molecule which binds to copper and prevents oxidation. The protected particles can enhance the thermal conductivity of methanol with no interference from the capping ligand.

Excitation Mechanism of Low-n Edge Harmonic Oscillations in Edge Localized Mode-Free, High Performance, Tokamak Plasmas.

The excitation mechanism for low-n edge harmonic oscillations in quiescent H-mode regimes is identified analytically. We show that the combined effect of diamagnetic and poloidal magnetohydrodynamic flows, with the constraint of a Doppler-like effect of the ion flow, leads to the stabilization of short wavelength modes, allowing low-n perturbation to grow. The analysis, performed in tokamak toroidal geometry, includes the effects of large edge pressure gradients, associated with the local flattening of the safety factor and diamagnetic flows, sheared parallel and E×B rotation, and a vacuum region between plasma and the ideal metallic wall. The separatrix also is modeled analytically.

Application of the VUV and the soft x-ray systems on JET for the study of intrinsic impurity behavior in neon seeded hybrid discharges.

This paper reports on impurity behavior in a set of hybrid discharges with Ne seeding-one of the techniques considered to reduce the power load on reactor walls. A series of experiments carried out with light gas injection on JET with the ITER-Like-Wall (ILW) suggests increased tungsten release and impurity accumulation [C. Challis et al., Europhysics Conference Abstracts 41F, 2.153 (2017)]. The presented method relies mainly on the measurements collected by vacuum-ultra-violet and soft X-ray (SXR) diagnostics including the "SOXMOS" spectrometer and the SXR camera system. Both diagnostics have some limitations. Consequently, only a combination of measurements from these systems is able to provide comprehensive information about high-Z [e.g., tungsten (W)] and mid-Z [nickel (Ni), iron (Fe), copper (Cu), and molybdenum (Mo)] impurities for their further quantitative diagnosis. Moreover, thanks to the large number of the SXR lines of sight, determination of a 2D radiation profile was also possible. Additionally, the experimental results were compared with numerical modeling based on integrated simulations with COREDIV. Detailed analysis confirmed that during seeding experiments, higher tungsten release is observed, which was also found in the past. Additionally, it was noticed that besides W, the contribution of molybdenum to SXR radiation was greater, which can be explained by the place of its origin.

Auditory Perception: Laurel and Yanny Together at Last.

An auditory illusion caught the world's attention recently. For the same noisy speech utterance, different people reported hearing either 'Laurel' or 'Yanny'. The dichotomy highlights how perceptions are inferences from inherently ambiguous sensory information, even though ambiguity is often unnoticed.

Organizations of food redistribution and rescue.

OBJECTIVE: Food insecurity affects 13.4% of the USA population, despite the fact that 30-40% of all food is deposited in a landfill. Food rescue nutrition is the process of redistribution of surplus food to the impoverished. The aim of this study is to document the extent of involvement of organizations in food rescue nutrition. STUDY DESIGN: In this cross-sectional study, a survey about organizations involved in food rescue nutrition was developed, validated, and then tested. METHOD: Directors of 100 organizations involved in food rescue nutrition from eight Southwestern States in the USA participated in this research. RESULTS: These organizations provided an average of 2 million kg of food to more than 40,000 clients each month. Food assistance programs had an average of eight workers and 3081 volunteers. In addition to food, these organizations provided other services such as clothing, clinical, and childcare. The agencies encountered several challenges, including lack of resources that resulted in reducing food portions and turning away clients. CONCLUSIONS: The extent of involvement of community-based programs in food rescue nutrition was strong in eight Southwestern states in the USA. Organizations involved in food redistribution helped alleviate food insecurity in their clients. Sustainability of these charitable networks was dependent on availability of resources and sufficient volunteers. Health professionals should encourage these organizations by providing support through donations of time, money, and/or food.

Motivations for volunteers in food rescue nutrition.

OBJECTIVE: A variety of organizations redistribute surplus food to low-income populations through food rescue nutrition. Why volunteers participate in these charitable organizations is unclear. The aim of this study is to document the participation and motivations of volunteers who are involved specifically in food rescue nutrition. STUDY DESIGN: A cross-sectional study was conducted in two phases. METHODS: In phase 1, a new instrument, Motivations to Volunteer Scale, was developed and validated in 40 participants (aged ≥18 years). In phase 2, the new scale and a demographics questionnaire were administered to 300 participants who were volunteering in food pantries and churches. RESULTS: The pilot study showed that Motivations to Volunteer Scale exhibited an internal consistency of Cronbach's α of 0.73 (P < 0.01), and a reliability from a test-retest of times 1 and 2 was r = 0.9 (P < 0.05); paired t-test was insignificant (P > 0.05). The scale was validated also by comparison to the Volunteer Function Inventory (r = 0.86, P < 0.05). The constructs of the newly developed Motivations to Volunteer Scale were requirement, career improvement, social life, and altruism. The mean motivation score of the 300 volunteers was 9.15 ± 0.17. Greater motivations were observed among participants who were aged >45 years, women, Hispanics, college/university graduates, physically inactive, non-smokers, and had an income ≥ $48,000. CONCLUSIONS: The Motivations to Volunteer Scale is a valid tool to assess why individuals volunteer in food rescue nutrition. The extent of motivations of participants was relatively high, and the primary reason for volunteering was altruism. Health professionals should be encouraged to participate in food redistribution.

Evaluating the association of allergies with multiple sclerosis susceptibility risk and disease activity in a pediatric population.

BACKGROUND: Multiple sclerosis (MS) and allergies are both considered to be related to imbalanced Th1 and Th2 immune responses. Previous studies evaluating the relationship between MS and allergies provide conflicting results. OBJECTIVE: To assess allergies and asthma as risk factors for MS and as predictors of MS relapses in a pediatric cohort. METHODS: The environment and genetic risk factors for pediatric MS study is a national case-control project with 16 participating US sites. An environmental questionnaire is used that includes history of allergies in the first five years of life. Case-control data are entered in the pediatric MS Network database and cases at 12 of the 16 sites enter relapse data prospectively. Annualized relapse rate was calculated for patients with follow-up and adjusted for age at disease onset, gender, race, ethnicity, and use of disease-modifying therapy (DMT). RESULTS: We included 271 cases (mean age at disease onset of 15.7years and 62% female) and 418 controls. Relapse data were available for 193 cases. There was no difference in prevalence of allergies or asthma between cases and controls. Patients with food allergies had fewer relapses compared to patients without food allergies (0.14 vs 0.48, p=0.01). CONCLUSIONS: While allergies and asthma are not associated with pediatric MS, cases with food allergies have fewer relapses compared to those without food allergies.

Genomics of Parallel Experimental Evolution in Drosophila.

What are the genomic foundations of adaptation in sexual populations? We address this question using fitness-character and whole-genome sequence data from 30 Drosophila laboratory populations. These 30 populations are part of a nearly 40-year laboratory radiation featuring 3 selection regimes, each shared by 10 populations for up to 837 generations, with moderately large effective population sizes. Each of 3 sets of the 10 populations that shared a selection regime consists of 5 populations that have long been maintained under that selection regime, paired with 5 populations that had only recently been subjected to that selection regime. We find a high degree of evolutionary parallelism in fitness phenotypes when most-recent selection regimes are shared, as in previous studies from our laboratory. We also find genomic parallelism with respect to the frequencies of single-nucleotide polymorphisms, transposable elements, insertions, and structural variants, which was expected. Entirely unexpected was a high degree of parallelism for linkage disequilibrium. The evolutionary genetic changes among these sexual populations are rapid and genomically extensive. This pattern may be due to segregating functional genetic variation that is abundantly maintained genome-wide by selection, variation that responds immediately to changes of selection regime.

Comparative morphology of the scales of roundscale spearfish Tetrapturus georgii and white marlin Kajikia albida.

The comparative morphology of the scales of roundscale spearfish Tetrapturus georgii and white marlin Kajikia albida was investigated. In addition, variation in scale morphology across different body regions within each species was analysed. Although considerable morphological variation was observed among scales from different body regions in both species, scales of K. albida generally have pointed anterior ends, fewer posterior points and are more heavily imbricated than those of T. georgii, which are frequently rounded anteriorly, often have many posterior points and are separated farther within the skin. In all sampled body regions and individuals, scales of T. georgii are significantly broader and have a lower length-to-width aspect ratio than those of K. albida. Superficial to the scales are denticular plates, which are ossified formations occurring on the surface layer of the epidermis; these were observed and described for T. georgii, K. albida and blue marlin Makaira nigricans. Detailed scale descriptions allow for a more accurate characterization of the variation within and differences between these two species and could potentially be a valuable tool for investigating istiophorid systematics.

Continuous daily assessment of multiple sclerosis disability using remote step count monitoring.

Disability measures in multiple sclerosis (MS) rely heavily on ambulatory function, and current metrics fail to capture potentially important variability in walking behavior. We sought to determine whether remote step count monitoring using a consumer-friendly accelerometer (Fitbit Flex) can enhance MS disability assessment. 99 adults with relapsing or progressive MS able to walk ≥2-min were prospectively recruited. At 4 weeks, study retention was 97% and median Fitbit use was 97% of days. Substudy validation resulted in high interclass correlations between Fitbit, ActiGraph and manual step count tally during a 2-minute walk test, and between Fitbit and ActiGraph (ICC = 0.76) during 7-day home monitoring. Over 4 weeks of continuous monitoring, daily steps were lower in progressive versus relapsing MS (mean difference 2546 steps, p < 0.01). Lower average daily step count was associated with greater disability on the Expanded Disability Status Scale (EDSS) (p < 0.001). Within each EDSS category, substantial variability in step count was apparent (i.e., EDSS = 6.0 range 1097-7152). Step count demonstrated moderate-strong correlations with other walking measures. Lower average daily step count is associated with greater MS disability and captures important variability in real-world walking activity otherwise masked by standard disability scales, including the EDSS. These results support remote step count monitoring as an exploratory outcome in MS trials.

N-Myc overexpression increases cisplatin resistance in neuroblastoma via deregulation of mitochondrial dynamics.

N-Myc is a global transcription factor that regulates the expression of genes involved in a number of essential cellular processes including: ribosome biogenesis, cell cycle and apoptosis. Upon deregulation, N-Myc can drive pathologic expression of many of these genes, which ultimately defines its oncogenic potential. Overexpression of N-Myc has been demonstrated to contribute to tumorigenesis, most notably for the pediatric tumor, neuroblastoma. Herein, we provide evidence that deregulated N-Myc alters the expression of proteins involved in mitochondrial dynamics. We found that N-Myc overexpression leads to increased fusion of the mitochondrial reticulum secondary to changes in protein expression due to aberrant transcriptional and post-translational regulation. We believe the structural changes in the mitochondrial network in response to N-Myc amplification in neuroblastoma contributes to two important aspects of tumor development and maintenance-bioenergetic alterations and apoptotic resistance. Specifically, we found that N-Myc overexpressing cells are resistant to programmed cell death in response to exposure to low doses of cisplatin, and demonstrated that this was dependent on increased mitochondrial fusion. We speculate that these changes in mitochondrial structure and function may contribute significantly to the aggressive clinical ph9enotype of N-Myc amplified neuroblastoma.

Depression, Anxiety, and Quality of Life In Children and Adolescents With Sickle Cell Disease.

The relationships among depression, anxiety, and quality of life were tested, as were the effects of age, gender, and pain frequency on these variables in children (n = 44) and adolescents (n = 31) with sickle cell disease. Participants completed the Revised Child Anxiety and Depression Scale (ROADS) and the Pediatric Quality of Life (PedQL Generic Model). The mean and standard deviation for summary RCADS scores for the majority of participants were below the clinical thresholds of T < 65, indicating low risk for depression (n = 65; 89.3%) and anxiety (n = 70; 93.3%). The subscale scores for the different dimensions of QOL health were a) psychosocial (73.3 ± 15.9), b) emotional (75.0 ± 20.7), c) social (80.8 ± 19.1), d) school functioning (64.0 ≥ 19.8), and e) physical (77.4 ± 17.4). Significant negative correlations were found between mean total quality of life scores and symptoms of a) general anxiety (r = -0.51, p < 0.0001), b) depression (r = -0.66, p < 0.0001), c) obsessive compulsive (r = -0.53, p < 0.0001), d) panic (r = -0.60, p < 0.0001), and e) social phobia (r = -0.57, p < 0.0001). Age and gender did not have significant effects on risk for depression and anxiety or poor QOL. Pain frequency also did not have significant effects on the risk for depression and anxiety. Findings suggest that health care providers need to screen for anxiety and depression, and make referrals for early interventions to improve quality of life and promote school function in youth with sickle cell disease.

Secondary contact and asymmetrical gene flow in a cosmopolitan marine fish across the Benguela upwelling zone.

The combination of oceanographic barriers and habitat heterogeneity are known to reduce connectivity and leave specific genetic signatures in the demographic history of marine species. However, barriers to gene flow in the marine environment are almost never impermeable which inevitably allows secondary contact to occur. In this study, eight sampling sites (five along the South African coastline, one each in Angola, Senegal and Portugal) were chosen to examine the population genetic structure and phylogeographic history of the cosmopolitan bluefish (Pomatomus saltatrix), distributed across a large South-east Atlantic upwelling zone. Molecular analyses were applied to mtDNA cytochrome b, intron AM2B1 and 15 microsatellite loci. We detected uncharacteristically high genetic differentiation (FST 0.15-0.20; P<0.001) between the fish sampled from South Africa and the other sites, strongly influenced by five outlier microsatellite loci located in conserved intergenic regions. In addition, differentiation among the remaining East Atlantic sites was detected, although mtDNA indicated past isolation with subsequent secondary contact between these East Atlantic populations. We further identified secondary contact, with unidirectional gene flow from South Africa to Angola. The directional contact is likely explained by a combination of the northward flowing offshore current and endogenous incompatibilities restricting integration of certain regions of the genome and limiting gene flow to the south. The results confirm that the dynamic system associated with the Benguela current upwelling zone influences species distributions and population processes in the South-east Atlantic.

Retinal axonal loss in very early stages of multiple sclerosis.

BACKGROUND AND PURPOSE: The lack of surrogates of clinical progression has limited the design of neuroprotection trials in multiple sclerosis (MS). Our aim was to study the association between time-domain optical coherence tomography measures and clinical and magnetic resonance imaging outcomes in early MS. METHODS: Forty-three relapsing-remitting MS patients within 1 year of onset were followed for up to 3 years. RESULTS: The peripapillary retinal nerve fiber layer (RNFL) decreased annually by 2 µm (95% confidence interval -3.89, -0.11; P = 0.038). The RNFL tended to be associated with normalized normal appearing white matter volume in cross-sectional (P = 0.08) and longitudinal analyses (P = 0.06). CONCLUSIONS: There is substantial RNFL loss even in very early MS. Our data suggest that retinal axonal atrophy is associated with atrophy in global white matter volume in early MS.