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The Best Practices in Social and Behavioral Research Course was developed to provide instruction on good clinical practice for social and behavioral trials. This study evaluated the new course.
Participants across 4 universities took the course (n=294) and were sent surveys following course completion and 2 months later. Outcomes included relevance, how engaging the course was, and working differently because of the course. Open-ended questions were posed to understand how work was impacted.
Participants rated the course as relevant and engaging (6.4 and 5.8/7 points) and reported working differently (4.7/7 points). Participants with less experience in social and behavioral trials were most likely to report working differently 2 months later.
The course was perceived as relevant and engaging. Participants described actions taken to improve rigor in implementing trials. Future studies with a larger sample and additional participating sites are recommended.
Experimental data are presented showing maximum carbon C6+ ion energies obtained from nm-scaled targets in the relativistic transparent regime for laser intensities between 9 × 1019 and 2 × 1021 W/cm2. When combined with two-dimensional particle-in-cell simulations, these results show a steep linear scaling for carbon ions with the normalized laser amplitude a0 (
$a_0 \propto \sqrt ( I)$
). The results are in good agreement with a semi-analytic model that allows one to calculate the optimum thickness and the maximum ion energies as functions of a0 and the laser pulse duration τλ for ion acceleration in the relativistic-induced transparency regime. Following our results, ion energies exceeding 100 MeV/amu may be accessible with currently available laser systems.
Due to its location and climate, Antarctica offers unique conditions
for long-period observations across a broad wavelength regime,
where important diagnostic lines for molecules and ions can be found,
that are essential to understand the chemical properties of the interstellar
medium. In addition to the natural benefits of the site, new
technologies, resulting from astrophotonics, may allow miniaturised instruments,
that are easier to winterise and advanced filters to further
reduce the background in the infrared.
The CRESST-II direct Dark Matter search is located in the Gran Sasso underground laboratories, Italy. CaWO4 crystals are used as scintillating targets for WIMP (weakly interacting massive particle) interactions. They are operated as cryogenic calorimeters in combination with a second cryogenic detector used to measure the scintillation light produced in the target crystal. For each particle interaction, the combination of phonon and light signals provides an event by event discrimination which allows to distinguish known particles (alphas, betas, gammas, neutrons) from the expected signal of WIMPs. A major upgrade of the setup comprises modifications of the shielding, installation of a muon-veto, and new read out electronics, as well as a new detector-support structure to accommodate up to 33 detector modules, i.e. 10 kg of target mass. The experiment was thereafter successfully commissioned in 2007. Data obtained during this commissioning phase from 2 detector modules are presented here. Combining the data collected with these two detector modules with data from one single module obtained during the CRESST-I phase, the experiment could already place a limit of ~6 × 10-7 pb for the spin independent WIMP-nucleon scattering cross section at a WIMP mass of ~60 GeV/c2.
EURECA (European Underground Rare Event Calorimeter Array) is an
astro-particle physics facility aiming to directly detect galactic dark
matter. The Laboratoire Souterrain de Modane has been selected as host
laboratory. The EURECA collaboration unites CRESST, EDELWEISS and the
Spanish-French experiment ROSEBUD, thus concentrating and focussing effort
on cryogenic detector research in Europe into a single facility. EURECA will
use a target mass of up to one ton, enough to explore WIMP – nucleon scalar
scattering cross sections in the region of 10-9 – 10-10 picobarn.
A major advantage of EURECA is the planned use of more than just one target
material (multi target experiment for WIMP identification).
We report on the self-assembled formation of iron nanowires from iron nanoparticles. Nanosized iron particles with a diameter of about 35 nm are synthesized by thermal decomposition of iron pentacarbonyl Fe(CO)5 in a hot wall reactor. This particle size is chosen to produce single domain ferromagnetic particles. As a result, the particles are attracted by magnetic forces, leading to iron nanowires of up to 300 μm in length. HRTEM and EELS investigations give detailed morphological, structural and chemical information. They reveal a big metallic iron core surrounded by an iron oxide shell with a thickness of 3-4 nm, originating from self limiting surface oxidation under ambient conditions. For electrical characterization, single iron wires are thermophoretically sampled on interdigital contacts. Impedance spectroscopy on single nanowires indicates both, capacitive and ohmic contributions to the overall conductivity. Magnetic properties are investigated with SQUID magnetometry. Magnetization measurements reveal a saturation magnetization of 160 emu/g at 5 K, which is more than 70% of the iron bulk value.
We report the synthesis of organized colloidal semiconductor nanocrystal / carbon singlewalled nanotube hybrid nanostructures. The synthetic protocol described here avoids the need for covalent chemical modification of carbon nanotube (CNT) surfaces. Specifically, InP quantum dots (QDs) and CdSe QDs were found to strongly adsorb onto the surfaces of carbon single-walled nanotubes (SWNTs) by gentle heating in organic solvents. Transmission electron microscopy (TEM) was used to characterize the semiconductor nanocrystal (NC) / SWNT assemblies, and revealed that the surfaces of the SWNT bundles template the adsorption of the NCs from solution. Small QDs were found to randomly absorb onto SWNTs, while larger QDs self-assembled into long linear chains. The nature of binding and ordering was investigated by simply considering van der Waals (vdW) forces for both NC-SWNT and NC-NC interactions. Quantum rods (QRs) were also found to adsorb along the nanotube surfaces. These findings have important implications for the synthesis of NC / SWNT hybrid nanostructures.
Phonological awareness skills are prerequisite to early reading, yet the development of phonological awareness is an understudied phenomenon. To identify factors that contribute to the development of phonological awareness, we investigated the longitudinal relationships among child background factors, structural oral language, and phonological awareness in a sample of 52 children from kindergarten to second grade and a subsample of this group who were nonreaders in kindergarten. Background measures were IQ, family literacy, socioeconomic status, and child's primary language; oral language measures were receptive and expressive semantics, syntax, and morphology; phonological awareness was measured by segmentation and blending. Principal component analysis of the structural language measures yielded a general oral language factor score. Regression analyses indicated that the background variables were unique predictors of kindergarten general oral language skill but did not predict phonological awareness skills. General oral language accounted for significant and substantial unique variance in phonological awareness each year for both the full sample and the subsample of nonreaders, controlling for reading ability. These findings suggest general oral language may contribute to the development of early reading through its significant influence on the development of phonological awareness.
Routine use of mupirocin to prevent staphylococcal infections is controversial. We assessed attitudes and practices of healthcare professionals attending the Fourth Decennial International Conference on Nosocomial and Healthcare-Associated Infections regarding mupirocin prophylaxis. Eighty percent of participants did not use mupirocin routinely. At the end of the session, 58% indicated they would consider increased use of mupirocin.
Abstract: A set of uranium compound particles relevant to contaminated soils and other environmental concerns surrounding uranium bioavailability were studied by electron energy-loss spectroscopy (EELS). Core-loss EELS results suggest that uranium 4+ compounds have an energy loss resolvable from 6+ compounds. Shoulders on the uranium O4,5 edge further distinguish UO2 from UF4. Low-loss characteristics distinguish carbon-free uranium oxide specimens on holey substrates. In the presence of carbon, correction techniques must be applied. Uranium oxides, fluorides, and minerals show a tendency toward reduction of uranium toward 4+ under the beam. The electron dose required to achieve the transformation from 6+ to 4+ is more severe than that usually required to obtain satisfactory spectra, but the possibility for reduction should be considered. The conditions for low-loss analysis need not be as vigorous as those for core losses, and can be done without altering the valence of most oxides.
This study examined relationships between oral language and literacy in a two-year,
multivariate design. Through empirical cluster analysis of a sample of 88 kindergarten children,
four oral language subtypes were identified based on measures of semantics, syntax,
metalinguistics, and oral narration. Validation efforts included (a) concurrent and predictive
analyses of subtype differences on reading, spelling, and listening comprehension measures
based on a priori hypotheses and (b) a comparison of the teacher classification of the children
with the empirical classification. The subtypes represented high average, low average, high
narrative, and low overall patterns of oral language skill. The high average subtype received the
most consistent evidence for validation. The pattern of validation results indicates that the
relationship between oral language and literacy is not uniform and suggests a modification of the
assumption that oral language skills have a direct role in reading acquisition.
Image sensors in TFA (Thin Film on ASIC) technology have been successfully fabricated and tested. This paper provides a survey of TFA research results so far and outlines future perspectives. The properties of different a-Si:H b/w and color thin film detectors are evaluated, including spectral sensitivity, dark current, temperature influence and transient behavior. Furthermore several TFA prototypes and emerging concepts are presented, ranging from a simple one-transistor cell design to a locally autoadaptive sensor.
The results of photometric and spectroscopic observations of dwarf novae are presented. The data were obtained during an international program of multiwavelength observations, held in 1986 February at several observatories, of dwarf novae during the first and subsequent days of outburst. During the campaign numerous dwarf novae were monitored in order to catch them in outburst. Preliminary results and analysis of some objects are reported elsewhere. A total of 30 dwarf novae were observed in the northern and southern hemispheres. Among them 37% were caught in outburst, including 10% on the rise to outburst and 17% in decline. Photometric observations were carried out in the UBVRI system and colour indexes were calculated.
This study examines psychological symptomatology in a cohort of 72 heart transplant recipients followed longitudinally during their first year post-transplant. In keeping with research on other domains of life stressors and illnesses, a central study goal was to identify pre-transplant and perioperative psychosocial factors associated with increased vulnerability to, and maintenance of, elevated psychological distress levels post-transplant. Average anxiety and depression levels, but not anger–hostility symptoms, were substantially elevated in the early post-transplant period, relative to normative data. Average symptom levels improved significantly over time, although one-third of the sample continued to have high distress levels at all follow-up assessments. Recipients with any of seven psychosocial characteristics at initial interview were particularly susceptible to continued high average distress levels over time: a personal history of psychiatric disorder prior to transplant; younger age; lower social support from their primary family caregiver; exposure to recent major life events involving loss; poor self-esteem; a poor sense of mastery; and use of avoidance coping strategies to manage health problems. Recipients without such factors showed improvement in average distress levels across the assessment period. These effects were stronger for anxiety than depressive symptoms, with the exception of a sizeable relationship between loss events and subsequent depression. The findings suggest that clinical interventions designed to minimize prolonged emotional distress post-transplant need to be closely tailored to heart recipients' initial psychosocial assets and liabilities.
NGC 2899 (PK 277-3°l, He 2-30, RCW 43) is a southern planetary nebula of fairly large angular size (∼2!6 × 1!4) and moderate high surface brightness. Its morphology strongly resembles a loose bipolar structure with conspicuous bright condensations of toroidal geometry placed along the minor axis, on each side of the central object.
The advantages of pulsed excimer lasers for semiconductor processing are reviewed. Studies of XeCl excimer laser annealing with pulses of 25 and 70 nsec duration and energy densities in the range from 0.5–3.0 J/cm2 are discussed. The annealing characteristics are described in terms of the results of melt depth, dopant profile spreading, and electrical properties (sheet resistivity, diode characteristics) measurements. Solar cells with efficiencies as high as 16.7% AMI have been fabricated using glow discharge implantation and XeCl laser annealing.