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Feasibility and Acceptability of the Modified Antiretroviral Treatment Access Study (MARTAS) Intervention Based on a Pilot Study in Ukraine.
We conducted a pilot of the Modified Antiretroviral Treatment Access Study (MARTAS), a linkage to HIV treatment intervention, prior to implementing a multisite randomized controlled trial (RCT) in Ukraine. The objectives of the pilot were to assess the feasibility and acceptability of the MARTAS intervention among a small sample of adults recently diagnosed with HIV at specialty clinics in the Mykolaiv region of Ukraine in 2015. The adapted intervention consisted of up to 6 individual-level sessions with a linkage coordinator (nurse) over a 90-day period. Overall, 22 persons participated in the pilot. On average, participants received 4.2 sessions and 14 participants linked to HIV care within 3 months of study enrollment. All 18 participants who completed the acceptability survey expressed high satisfaction with their interaction with their linkage coordinator. The results of the pilot demonstrated feasibility and acceptability of the MARTAS intervention in advance of a larger scale RCT in Ukraine
Three-Dimensional Magnetohydrodynamics Simulations Of Counter-Helicity Spheromak Merging In The Swarthmore Spheromak Experiment
Recent counter-helicity spheromak merging experiments in the Swarthmore Spheromak Experiment (SSX) have produced a novel compact torus (CT) with unusual features. These include a persistent antisymmetric toroidal magnetic field profile and a slow, nonlinear emergence of the n = 1 tilt mode. Experimental measurements are inconclusive as to whether this unique CT is a fully merged field-reversed configuration (FRC) with strong toroidal field or a partially merged doublet CT configuration with both spheromak- and FRC-like characteristics. In this paper, the SSX merging process is studied in detail using three-dimensional resistive MHD simulations from the Hybrid Magnetohydrodynamics (HYM) code. These simulations show that merging plasmas in the SSX parameter regime only partially reconnect, leaving behind a doublet CT rather than an FRC. Through direct comparisons, we show that the magnetic structure in the simulations is highly consistent with the SSX experimental observations. We also find that the n = 1 tilt mode begins as a fast growing linear mode that evolves into a slower-growing nonlinear mode before being detected experimentally. A simulation parameter scan over resistivity, viscosity, and line-tying shows that these parameters can strongly affect the behavior of both the merging process and the tilt mode. In fact, merging in certain parameter regimes is found to produce a toroidal-field-free FRC rather than a doublet CT. (C) 2011 American Institute of Physics. [doi:10.1063/1.3660533
Do Scapular Kinematics Alter during the Performance of the Scapular Assistance Test and Scapular Retraction Test: A Pilot Study
Objective: To describe to what degree and in what plane biomechanical alterations occur during the performance of the Scapular Retraction test (SRT) and Scapular Assistance Test (SAT).
Design: Laboratory Pilot Study
Participants: Eight symptomatic and 7 asymptomatic subjects were instrumented with electromagnetic sensors.
Main Outcome Measures: The SRT and SAT were performed with the scapula stabilized and unstabilized. The scapular kinematic variables of posterior tilt, internal rotation, upward rotation, protraction, and elevation were measured during both tests.
Results: Descriptive analysis of scapular kinematics suggested that posterior tilt was primarily increased during both clinical tests in both groups. Both groups decreased in scapular elevation, indicating that the scapula was being depressed during the SRT. There was no meaningful change in force during the SRT.
Conclusion: These findings indicate that both the SRT and SAT appear to alter scapular motion in both groups. The interpretations of these results are limited due to the small sample size and large confidence intervals, but suggest that these tests change specific positions of the scapula. Further research into these tests is needed to confirm these biomechanical alterations, and to determine the value of these tests when developing rehabilitation protocols in patients with shoulder pain
Improvement of Soil and Rock Properties for Foundation Support for Missouri Interchange Project
Expansion and growth in the southwestern region of Missouri necessitated the expansion of State Route 249 and the construction of a new interchange to provide service to the Joplin, Missouri area. The project is located above a former lead and zinc mine in Jasper County, Missouri and includes a five bridge interchange connecting State Route 249 and US Route 171. The variable subsurface conditions, both natural and manmade prompted the design team to use ground improvement via grouting and small diameter micropiles to provide support for several of the bridge foundations on the project. The scope of work included mine shaft closures, 17,070 m (56,000 ft) of overburden and rock drilling, 3,400 m (11,155 ft) of micropiles, 400 mÂł (524 cy) of balanced/stabilized high mobility grouts, and over 6,800 mÂł (8,900 cy) of low mobility grout. The selection of the grout used was based on the actual subsurface conditions. Low mobility grout (LMG) was used in voided conditions and for closure of the mine shafts encountered during the excavation. High mobility grout (HMG) was used in fractured rock with the goal of improving the mechanical properties of the rock underneath the future bridge footings and controlling grout volumes during micropile installation. The split spacing method was utilized for both LMG and HMG holes. Geology of the project consisted of extremely variable bedrock with strong to very strong limestone, chert, breccia, extremely weak shale, and weak to strong sandstone in conjunction with the activities associated with the mining disturbance (such as partial filled vertical mine shafts, shallow and deep mine horizons, modified hydrology including artesian conditions). Real time monitoring and recording of all drilling and grouting parameters was conducted to assist in the evaluation of in-situ geological properties of the site in order to modify the ground improvement and micropile program as necessary. This paper will discuss the design and execution of the ground improvement and micropile program. The project is an excellent example of the use of multiple ground improvement and foundation support techniques combined with real time data analysis to provide a foundation support solution for a complex geological environment
World-sheet Instantons via the Myers Effect and N=1^* Quiver Superpotentials
In this note we explore the stringy interpretation of non-perturbative
effects in N=1^* deformations of the A_{k-1} quiver models. For certain types
of deformations we argue that the massive vacua are described by Nk fractional
D3-branes at the orbifold polarizing into k concentric 5-brane spheres each
carrying fractional brane charge. The polarization of the D3-branes induces a
polarization of D-instantons into string world-sheets wrapped on the Myers
spheres. We show that the superpotentials in these models are indeed generated
by these world-sheet instantons. We point out that for certain parameter values
the condensates yield the exact superpotential for a relevant deformation of
the Klebanov-Witten conifold theory.Comment: 24 pages, JHEP, some small errors and typos correcte
The Spitzer c2d Survey of Nearby Dense Cores: III: Low Mass Star Formation in a Small Group, L1251B
We present a comprehensive study of a low-mass star-forming region,L1251B, at
wavelengths from the near-infrared to the millimeter. L1251B, where only one
protostar, IRAS 22376+7455, was known previously, is confirmed to be a small
group of protostars based on observations with the Spitzer Space Telescope. The
most luminous source of L1251B is located 5" north of the IRAS position. A
near-infrared bipolar nebula, which is not associated with the brightest object
and is located at the southeast corner of L1251B, has been detected in the IRAC
bands. OVRO and SMA interferometric observations indicate that the brightest
source and the bipolar nebula source in the IRAC bands are deeply embedded disk
sources.Submillimeter continuum observations with single-dish telescopes and
the SMA interferometric observations suggest two possible prestellar objects
with very high column densities. Outside of the small group, many young stellar
object candidates have been detected over a larger region of 12' x 12'.
Extended emission to the east of L1251B has been detected at 850 micron; this
"east core" may be a site for future star formation since no point source has
been detected with IRAC or MIPS. This region is therefore a possible example of
low-mass cluster formation, where a small group of pre- and protostellar
objects (L1251B) is currently forming, alongside a large starless core (the
east core).Comment: 35 pages, 15 figures, accepted for publication in ApJ, for the full
resolution paper, visit
"http://peggysue.as.utexas.edu/SIRTF/PAPERS/pap27.pub.pdf
Preparation for Hollow Cathode Testing for the Advanced Electric Propulsion System at NASA Glenn Research Center
NASA Glenn Research Center is performing activities to support the unique needs of hollow cathode development and testing for the Advanced Electric Propulsion System (AEPS). Three existing vacuum facilities have been outfitted as cathode test facilities, and each will serve a different role in upcoming testing. Vacuum Facility 67 is being developed to serve as a long-duration test facility for the Engineering Development Unit cathode, which is to be delivered by the AEPS contractor. It will feature a thruster-like magnetic field simulator and cold-cycle capability via a liquid nitrogen-cooled cold plate. Vacuum Facility 17 is being developed as a test facility for short- to medium-duration experiments in order to provide auxiliary support for the long-duration testing. It will feature a magnetic field simulator but not cold-cycling. Finally, Vacuum Facility 1 will be a high-pumping speed cathode development environment, and will feature an array of plasma and temperature diagnostics. In addition to the facility preparation work, a new cathode, referred to as the Mark II, has been designed. The Mark II is an evolution of the Technology Demonstration Unit cathodes that better evokes the geometry, fabrication, and construction of the forthcoming Engineering Development Unit. This cathode serves as a transition between the Technology Demonstration Unit cathodes used during early thruster development and the forthcoming Engineering Development Unit cathodes. It will be used as a means of verifying the new test facilities prior to arrival of Engineering Development Unit hardware. Details of the Mark II design and key features are presented, as well as details of future work to be performed
Reliability of an Observational Method Used to Assess Tennis Serve Mechanics in a Group of Novice Raters
Background: Previous research has developed an observational tennis serve analysis (OTSA) tool to assess serve mechanics. The OTSA has displayed substantial agreement between the two health care professionals that developed the tool; however, it is currently unknown if the OTSA is reliable when administered by novice users.
Purpose: The purpose of this investigation was to determine if reliability for the OTSA could be established in novice users via an interactive classroom training session.
Methods: Eight observers underwent a classroom instructional training protocol highlighting the OTSA. Following training, observers participated in two different rating sessions approximately a week apart. Each observer independently viewed 16 non-professional tennis players performing a first serve. All observers were asked to rate the tennis serve using the OTSA. Both intra and inter-observer reliability were determined using Kappa coefficients.
Results: Kappa coefficients for intra and inter-observer agreement ranged from 0.09 to 0.83 depending on the body position. A majority of all body positions yeilded moderate agreement and higher.
Conclusion: This study suggests that the majority of components associated with the OTSA are reliable and can be taught to novice users via a classroom training session
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