A streamlined method for chiral fermions on the lattice

We discuss the use of renormalization counterterms to restore the chiral gauge symmetry in a lattice theory of Wilson fermions. We show that a large class of counterterms can be implemented automatically by making a simple modification to the fermion determinant.Comment: 4 pages, ANL-HEP-CP-92-10

The Role of Functional, Social, and Mobility Dynamics in Facilitating Older African Americans Participation in Clinical Research

Purpose: Older African Americans experience disproportionately higher incidence of morbidity and mortality related to chronic and infectious diseases, yet are significantly underrepresented in clinical research compared to other racial and ethnic groups. This study aimed to understand the extent to which social support, transportation access, and physical impediments function as barriers or facilitators to clinical trial recruitment of older African Americans. Methods: Participants (N=221) were recruited from six African American churches in Atlanta and surveyed on various influences on clinical trial participation

What about lay counselors' experiences of task-shifting mental health interventions? Example from a family-based intervention in Kenya.

Background:A key focus of health systems strengthening in low- and middle-income countries is increasing reach and access through task-shifting. As such models become more common, it is critical to understand the experiences of lay providers because they are on the forefront for delivering care services. A greater understanding would improve lay provider support and help them provide high-quality care. This is especially the case for those providing mental health services, as providing psychological care may pose unique stressors. We sought to understand experiences of lay counselors, focusing on identity, motivation, self-efficacy, stress, and burnout. The goal was to understand how taking on a new provider role influences their lives beyond simply assuming a new task, which would in turn help identify actionable steps to improve interventions with task-shifting components. Methods:Semi-structured interviews (n = 20) and focus group discussions (n = 3) were conducted with three lay counselor groups with varying levels of experience delivering a community-based family therapy intervention in Eldoret, Kenya. Thematic analysis was conducted, including intercoder reliability checks. A Stress Map was created to visualize stress profiles using free-listing and pile-sorting data collected during interviews and focus group discussions. Results:Counselors described high intrinsic motivation to become counselors and high self-efficacy after training. They reported positive experiences in the counselor role, with new skills improving their counseling and personal lives. As challenges arose, including client engagement difficulties and balancing many responsibilities, stress and burnout increased, dampening motivation and self-efficacy. In response, counselors described coping strategies, including seeking peer and supervisor support, that restored their motivation to persevere. At case completion, they again experienced high self-efficacy and a desire to continue. Conclusions:Findings informed suggestions for ways to incorporate support for lay providers into task-shifting interventions at initiation, during training, and throughout implementation. These include acknowledging and preparing counselors for challenges during training, increasing explicit attention to counselor stress in supervision, fostering peer support among lay providers, and ensuring a fair balance between workload and compensation. Improving and building an evidence base around practices for supporting lay providers will improve the effectiveness and sustainability of lay provider-delivered interventions

Enrollment in YFV Vaccine Trial: An Evaluation of Recruitment Outcomes Associated with a Randomized Controlled Double-Blind Trial of a Live Attenuated Yellow Fever Vaccine

This investigation evaluated several factors associated with diverse participant enrollment of a clinical trial assessing safety, immunogenicity, and comparative viremia associated with administration of 17-D live, attenuated yellow fever vaccine given alone or in combination with human immune globulin. We obtained baseline participant information (e.g., sociodemographic, medical) and followed recruitment outcomes from 2005 to 2007. Of 355 potential Yellow Fever vaccine study participants, 231 cases were analyzed. Strong interest in study participation was observed among racial and ethnically diverse persons with 36.34% eligible following initial study screening, resulting in 18.75% enrollment. The percentage of white participants increased from 63.66% (prescreened sample) to 81.25% (enrollment group). The regression model was significant with white race as a predictor of enrollment (OR=2.744, 95% CI=1.415-5.320, p=0.003).In addition, persons were more likely to enroll via direct outreach and referral mechanisms compared to mass advertising (OR=2.433, 95% CI=1.102-5.369). The findings indicate that racially diverse populations can be recruited to vaccine clinical trials, yet actual enrollment may not reflect that diversit

Self-Similar Magnetocentrifugal Disk Winds with Cylindrical Asymptotics

We construct a two-parameter family of models for self-collimated, radially self-similar magnetized outflows from accretion disks. A flow at zero initial poloidal speed leaves the surface of a rotating disk and is accelerated and redirected toward the pole by helical magnetic fields threading the disk. At large distances from the disk, the flow streamlines asymptote to wrap around the surfaces of nested cylinders. In constrast to previous disk wind modeling, we have explicitly implemented the cylindrical asymptotic boundary condition to examine the consequences for flow dynamics. The solutions are characterized by the logarithmic gradient of the magnetic field strength and the ratios between the footpoint radius R_0 and asymptotic radius R_1 of streamlines; the Alfven radius must be found as an eigenvalue. Cylindrical solutions require the magnetic field to drop less steeply than 1/R. We find that the asymptotic poloidal speed on any streamline is typically just a few tenths of the Kepler speed at the corresponding disk footpoint. The asymptotic toroidal Alfven speed is, however, a few times the footpoint Kepler speed. We discuss the implications of the models for interpretations of observed optical jets and molecular outflows from young stellar systems. We suggest that the difficulty of achieving strong collimation in vector velocity simultaneously with a final speed comparable to the disk rotation rate argues against isolated jets and in favor of models with broader winds.Comment: 39 pages, Latex (uses AAS Latex macros), 6 eps figures, postscript preprint with embedded figures available from http://www.astro.umd.edu/~ostriker/professional/publications.html , to appear in ApJ 9/1/9

Hyper- and suspended-accretion states of rotating black holes and the durations of gamma-ray bursts

We analyze the temporal evolution of accretion onto rotating black holes subject to large-scale magnetic torques. Wind torques alone drive a disk towards collapse in a finite time $\sim t_{ff} E_k/E_B$, where $t_{ff}$ is the initial free-fall time and $E_k/E_B$ is the ratio of kinetic-to-poloidal magnetic energy. Additional spin-up torques from a rapidly rotating black hole can arrest the disk's inflow. We associate short/long gamma-ray bursts with hyperaccretion/suspended-accretion onto slowly/rapidly spinning black holes. This model predicts afterglow emission from short bursts, and may be tested by HETE-II.Comment: accepted for publication in the ApJ

Physiothérapie et douleur lombo-pelvienne chez la femme enceinte : Un appel à l’action

Travail d'intégration présenté à Isabelle Gagnon dans le cadre du cours PHT-6113.Problématique : La douleur lombo-pelvienne est une plainte fréquemment rencontrée chez la femme enceinte. Selon les études, l’incidence varie de 24% à 90%. Le mythe que la douleur lombo-pelvienne fait partie du processus normal de la grossesse et la croyance répandue qu’il n’y a rien à faire pour limiter les symptômes font en sorte que cette clientèle est sous-traitée par les physiothérapeutes. Objectifs : Les objectifs du projet étaient 1) d’explorer la pratique clinique actuelle en physiothérapie ainsi que l’attitude des physiothérapeutes face à la prise en charge de femmes enceintes souffrant de douleurs lombo-pelviennes, 2) d’identifier la prise en charge optimale à préconiser et 3) d’élaborer des stratégies de transfert des connaissances acquises. Méthodes : Un sondage a été effectué auprès de physiothérapeutes afin de déterminer la pratique clinique actuelle et leur sentiment de compétence face à cette clientèle. De plus, une recension des écrits concernant l’épidémiologie, les changements physiologiques, l’évaluation et le traitement en physiothérapie a été réalisée. Finalement, un site web visant les professionnels de la physiothérapie fut préparé. Résultats : Des incertitudes quant aux précautions et contre-indications à prendre face à l’évaluation (19,7%), au traitement (40,3%) et à la prescription d’entrainement musculaire (25,2%) et cardio-vasculaire (35,1%) persistent chez un nombre important de physiothérapeutes. Lors de l’évaluation, il est particulièrement important de différencier les douleurs d’origine lombaire et pelvienne. Il semble y avoir des évidences sur l’efficacité des exercices en piscine ainsi que sur l’acuponcture pour traiter cette clientèle. Conclusion : L’insuffisance d’évidences scientifiques ainsi que le manque de confiance des physiothérapeutes en ce qui concerne la pratique limitent la prise en charge optimale de cette clientèle

Interpersonal competencies define effective conservation leadership

Effective leadership is considered essential for conservation success, but there is currently not enough understanding of what conservation leaders are doing, and what they should be doing, in order to be effective. Other sectors, such as health, commerce, education, industry and the military have studied leadership for decades, and have a good knowledge of particular styles and suitable instruments for measuring leadership effectiveness. This study uses the perspectives of conservation professionals through interviews, a focus group and an online survey, to help develop a more comprehensive picture of the role of leaders, and leadership, within the discipline. The study concludes that competencies that relate to interpersonal leadership skills are key for effectiveness, particularly building trust amongst followers. However, leaders in conservation are not showing these to the same extent as they are showing more technical skills. Future conservation training schemes should incorporate these competencies to ensure leaders are effective. Greater understanding can help inform conservation professionals who wish to invest in leadership development schemes to improve effectiveness across conservation initiatives