Coupled Vlasov and two-fluid codes on GPUs

We present a way to combine Vlasov and two-fluid codes for the simulation of a collisionless plasma in large domains while keeping full information of the velocity distribution in localized areas of interest. This is made possible by solving the full Vlasov equation in one region while the remaining area is treated by a 5-moment two-fluid code. In such a treatment, the main challenge of coupling kinetic and fluid descriptions is the interchange of physically correct boundary conditions between the different plasma models. In contrast to other treatments, we do not rely on any specific form of the distribution function, e.g. a Maxwellian type. Instead, we combine an extrapolation of the distribution function and a correction of the moments based on the fluid data. Thus, throughout the simulation both codes provide the necessary boundary conditions for each other. A speed-up factor of around 20 is achieved by using GPUs for the computationally expensive solution of the Vlasov equation and an overall factor of at least 60 using the coupling strategy combined with the GPU computation. The coupled codes were then tested on the GEM reconnection challenge

EXIT STRATEGY: PROJECTED LIFETIME RETURNS FOR CURRENT AND LEGACY RETIREMENT SCHEMES IN THE AUSTRALIAN DEFENCE FORCE

Incentives matter. Retirement savings after a lifetime of service are arguably the single largest windfall that most military members will ever see; yet curiously, estimating their worth as a labor incentive seems distant and obscure. This thesis quantifies Australian military retirement savings in both the legacy-defined benefit scheme (MilitarySuper) and the replacement-defined contribution scheme (ADFSuper). Comparative retirement savings were generated under different financial market conditions and for different rank cohorts. This research finds that over a lifetime of service, even modest market growth is sufficient for ADFSuper to significantly exceed the maximum returns possible in MilitarySuper. However, the range of possible solutions is wide, albeit dependent only on a few variables. Conversely, MilitarySuper’s range of outcomes is narrower, delivering greater certainty to members. However, it is more strongly impacted by factors exogenous to both the employee and the employer. This makes making modeling MilitarySuper more complex and the task of communicating its benefits more difficult. While the benefits of ADFSuper are readily communicable, the scheme does constitute a greater risk exposure for the member but not for the employer. The exact nature of this risk may be poorly understood by members of both schemes. Finally, this thesis postulates the effects that distant and obscure incentives may have on military recruitment and retention.Lieutenant Commander, Royal Australian NavyApproved for public release. Distribution is unlimited

Injustice perceptions about pain: parent–child discordance is associated with worse functional outcomes

Pain is experienced within and influenced by social environments. For children with chronic pain, the child–parent relationship and parental beliefs about pain are particularly important and may influence pain outcomes. Pain-related injustice perceptions have recently been identified as an important cognitive–emotional factor for children with pain. The current study aimed to better understand the pain-related injustice perceptions of children with chronic pain and their parents. The sample consisted of 253 pediatric chronic pain patients (mean age = 14.1 years, 74% female) presenting to a tertiary pain clinic. Patients completed measures of pain intensity, pain-related injustice perceptions, stress, functional disability, and quality of life. Parents completed a measure of pain-related injustice perceptions about their child's pain. Child–parent dyads were categorized into 1 of 4 categories based on the degree of concordance or discordance between their scores on the injustice measures. One-way analysis of variances examined differences in pain intensity, stress, functional disability, and quality of life across the 4 dyad categories. Our findings indicated that both the degree (concordant vs discordant) and direction (discordant low child–high parent vs discordant high child–low parent) of similarity between child and parent injustice perceptions were associated with child-reported pain intensity, stress, functional disability, and quality of life. The poorest outcomes were reported when children considered their pain as highly unjust, but their parents did not. These findings highlight the important role of parents in the context of pain-related injustice perceptions in pediatric chronic pain

Pain intensity and attribution mediate the impact of patient weight and gender on activity recommendations for chronic pain

Background and purpose: Despite the notable benefits of physical activity for chronic pain, a large proportion of patients with chronic pain report that they do not receive activity-related recommendations from their providers. Research suggests that patient factors such as weight and gender influence activity-related recommendations for chronic pain. Research also suggests that appraisals of the intensity and cause of pain may explain these weight and gender effects. We investigated the influence of patient weight and gender on observers' likelihood of recommending activity-related treatments for pain. We also explored the mediating effects of observers' ratings of pain severity and the extent to which pain was due to medical and lifestyle factors (pain attribution). Patients and methods: Healthy young adults (N=616; 76% female) viewed videos (Ghent Pain Videos of Daily Activities) and vignettes of 4 patients with chronic back pain performing a standardized functional task. Patients varied by gender (female, male) and weight (normal, obese), but were otherwise equivalent on demographic characteristics and pain behaviors. Participants rated how much pain they perceived the patients to be experiencing, the extent to which they attributed the pain to medical and lifestyle factors, and their likelihood of recommending exercise, physical therapy (PT), and rest. Results: Patient weight and gender significantly interacted to influence exercise, PT, and rest recommendations. Both pain intensity and pain attribution mediated the relationships between patient weight and activity recommendations; however, these mediation effects differed across gender and recommendation type. Conclusion: Patient weight and gender influenced laypeople's activity recommendations for chronic pain. Moreover, the results suggest that observers' perceptions of pain intensity and pain attributions are mechanisms underlying these effects. If these findings are replicated in providers, interventions may need to be developed to reduce provider biases and increase their recognition of the benefits of physical activity for chronic pain

A catalytic asymmetric total synthesis of (-)-perophoramidine

We report a catalytic asymmetric total synthesis of the ascidian natural product perophoramidine. The synthesis employs a molybdenum-catalyzed asymmetric allylic alkylation of an oxindole nucleophile and a monosubstituted allylic electrophile as a key asymmetric step. The enantioenriched oxindole product from this transformation contains vicinal quaternary and tertiary stereocenters, and is obtained in high yield along with high levels of regio-, diastereo-, and enantioselectivity. To install the second quaternary stereocenter in the target, the route utilizes a novel regio- and diastereoselective allylation of a cyclic imino ether to deliver an allylated imino ether product in near quantitative yield and with complete regio- and diastereocontrol. Oxidative cleavage and reductive amination are used as final steps to access the natural product.John Stauffer Memorial FellowshipStanford Graduate Fellowshi

Breakdown characteristics of an isolated conducting object in a uniform electric field

A laboratory experiment was conducted to determine the physical processes involved in the electrical breakdown of a particular spark gap arrangement. The gap consists of an isolated conducting ellipsoid located midway between two large flat electrodes. Gradual increase of the applied electric field, E, in the gap produces corona on the ellipsoid tips followed by flashover in a leader-arc sequence. The leader phase consists of the abrupt formation of ionized channels which partially bridge the gap and then decay prior to the arc. Measurements of dE/dt and of current were made, and photographs were taken with an image converter. Experimental parameters are listed

Dark complexes of the Calvin-Benson cycle in a physiological perspective

: Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and phosphoribulokinase (PRK) are two enzymes of the Calvin Benson cycle that stand out for some peculiar properties they have in common: (i) they both use the products of light reactions for catalysis (NADPH for GAPDH, ATP for PRK), (ii) they are both light-regulated through thioredoxins and (iii) they are both involved in the formation of regulatory supramolecular complexes in the dark or low photosynthetic conditions, with or without the regulatory protein CP12. In the complexes, enzymes are transiently inactivated but ready to recover full activity after complex dissociation. Fully active GAPDH and PRK are in large excess for the functioning of the Calvin-Benson cycle, but they can limit the cycle upon complex formation. Complex dissociation contributes to photosynthetic induction. CP12 also controls PRK concentration in model photosynthetic organisms like Arabidopsis thaliana and Chlamydomonas reinhardtii. The review combines in vivo and in vitro data into an integrated physiological view of the role of GAPDH and PRK dark complexes in the regulation of photosynthesis

Seeking Optimum System Settings for Physical Activity Recognition on Smartwatches

Physical activity recognition (PAR) using wearable devices can provide valued information regarding an individual's degree of functional ability and lifestyle. In this regards, smartphone-based physical activity recognition is a well-studied area. Research on smartwatch-based PAR, on the other hand, is still in its infancy. Through a large-scale exploratory study, this work aims to investigate the smartwatch-based PAR domain. A detailed analysis of various feature banks and classification methods are carried out to find the optimum system settings for the best performance of any smartwatch-based PAR system for both personal and impersonal models. To further validate our hypothesis for both personal (The classifier is built using the data only from one specific user) and impersonal (The classifier is built using the data from every user except the one under study) models, we tested single subject validation process for smartwatch-based activity recognition.Comment: 15 pages, 2 figures, Accepted in CVC'1