The matter in extreme conditions end station at the Linac Coherent Light Source (LCLS) is a new tool enabling accurate pump-probe measurements for studying the physical properties of matter in the ...high-energy density (HED) physics regime. This instrument combines the world's brightest x-ray source, the LCLS x-ray beam, with high-power lasers consisting of two nanosecond Nd:glass laser beams and one short-pulse Ti:sapphire laser. These lasers produce short-lived states of matter with high pressures, high temperatures or high densities with properties that are important for applications in nuclear fusion research, laboratory astrophysics and the development of intense radiation sources. In the first experiments, we have performed highly accurate x-ray diffraction and x-ray Thomson scattering measurements on shock-compressed matter resolving the transition from compressed solid matter to a co-existence regime and into the warm dense matter state. These complex charged-particle systems are dominated by strong correlations and quantum effects. They exist in planetary interiors and laboratory experiments, e.g., during high-power laser interactions with solids or the compression phase of inertial confinement fusion implosions. Applying record peak brightness x-rays resolves the ionic interactions at atomic (Ångstrom) scale lengths and measure the static structure factor, which is a key quantity for determining equation of state data and important transport coefficients. Simultaneously, spectrally resolved measurements of plasmon features provide dynamic structure factor information that yield temperature and density with unprecedented precision at micron-scale resolution in dynamic compression experiments. These studies have demonstrated our ability to measure fundamental thermodynamic properties that determine the state of matter in the HED physics regime.
High‐resolution inelastic X‐ray scattering is an established technique in the synchrotron community, used to investigate collective low‐frequency responses of materials. When fielded at hard X‐ray ...free‐electron lasers (XFELs) and combined with high‐intensity laser drivers, it becomes a promising technique for investigating matter at high temperatures and high pressures. This technique gives access to important thermodynamic properties of matter at extreme conditions, such as temperature, material sound speed, and viscosity. The successful realization of this method requires the acquisition of many identical laser‐pump/X‐ray‐probe shots, allowing the collection of a sufficient number of photons necessary to perform quantitative analyses. Here, a 2.5‐fold improvement in the energy resolution of the instrument relative to previous works at the Matter in Extreme Conditions (MEC) endstation, Linac Coherent Light Source (LCLS), and the High Energy Density (HED) instrument, European XFEL, is presented. Some aspects of the experimental design that are essential for improving the number of photons detected in each X‐ray shot, making such measurements feasible, are discussed. A careful choice of the energy resolution, the X‐ray beam mode provided by the XFEL, and the position of the analysers used in such experiments can provide a more than ten‐fold improvement in the photometrics. The discussion is supported by experimental data on 10 µm‐thick iron and 50 nm‐thick gold samples collected at the MEC endstation at the LCLS, and by complementary ray‐tracing simulations coupled with thermal diffuse scattering calculations.
High‐resolution inelastic X‐ray scattering measurements at hard X‐ray free‐electron lasers coupled with energetic laser drivers have shown a 2.5‐fold improved energy resolution compared with previous experiments at similar XFEL instruments. Aspects of the experimental design that can be adjusted to improve the number of recorded photons on the detector are discussed.
To evaluate the efficacy of a paraprofessional-delivered, home-visiting intervention among young, reservation-based American Indian (AI) mothers on parenting knowledge, involvement, and maternal and ...infant outcomes.
From 2002 to 2004, expectant AI women aged 12 to 22 years (n = 167) were randomized (1:1) to one of two paraprofessional-delivered, home-visiting interventions: the 25-visit "Family Spirit" intervention addressing prenatal and newborn care and maternal life skills (treatment) or a 23-visit breast-feeding/nutrition education intervention (active control). The interventions began during pregnancy and continued to 6 months postpartum. Mothers and children were evaluated at baseline and 2, 6, and 12 months postpartum. Primary outcomes included changes in mothers' parenting knowledge and involvement. Secondary outcomes included infants' social and emotional behavior; the home environment; and mothers' stress, social support, depression, and substance use.
Participants were mostly teenaged, first-time, unmarried mothers living in reservation communities. At 6 and 12 months postpartum, treatment mothers compared with control mothers had greater parenting knowledge gains, 13.5 (p < .0001) and 13.9 (p < .0001) points higher, respectively (100-point scale). At 12 months postpartum, treatment mothers reported their infants to have significantly lower scores on the externalizing domain (beta = -.17, p < .05) and less separation distress in the internalizing domain (beta = -.17, p < .05). No between-group differences were found for maternal involvement, home environment, or mothers' stress, social support, depression, or substance use.
This study supports the efficacy of the paraprofessional-delivered Family Spirit home-visiting intervention for young AI mothers on maternal knowledge and infant behavior outcomes. A longer, larger study is needed to replicate results and evaluate the durability of child behavior outcomes.
Objective To assess alterations in the regional perfusion and oxygenation of the calf muscles in individuals with diabetes. Methods Age-matched individuals with (n = 5) and without diabetes (n = 6) ...were investigated. Skeletal muscle perfusion, oxygen extraction fraction, and oxygen consumption rate were measured by newly developed noncontrast magnetic resonance imaging (MRI) techniques. The subjects lay supine on the MRI table with their foot firmly strapped to a custom-built isometric exercise device. The measurements were performed at rest and during an isometric plantar flexion muscle contraction. Results Individuals without diabetes had up to a 10-fold increase in muscle perfusion, 25% elevation in muscle oxygen extraction fraction, and a 12-fold increase in oxygen consumption rate in the calf during the plantar flexion isometric contraction. In patients with diabetes, the increases in these parameters were only up to sixfold, 2%, and sixfold, respectively. Exercise oxygen consumption rate was inversely associated with blood HbA1c levels ( r2 = .91). Conclusions This is the first study to quantify regional skeletal muscle oxygenation in patients with diabetes using noncontrast MRI and warrants additional study. Attenuation of perfusion and oxygenation during exercise may have implications for understanding diabetic complications in the lower extremities.
Before the COVID-19 pandemic, questions about the increased use of telemedicine had become common in conversations among medical providers. With the onset of the pandemic, these questions became more ...pronounced, and quick implementation became the key. New and historic barriers to telemedicine began to emerge at a dramatically increased rate during its rapid mobilization. However, considering how quickly telemedicine has been implemented, the impact on frontline workers, such as social workers, has not been specifically explored. We wondered how the change from face-to-face care to using digital platforms for care delivery has affected social work. Could social work ensure the fluid rollout of digital treatment platforms for care management? Could social work balance the increased number of digital treatment platforms with self-care for social workers during the COVID-19 crisis? What were some history social- work-preparedness plans used for other pandemics, and would those plans work for the COVID-19 pandemic? What were some of the self-care techniques employed by social workers? What were the emerging best practices of social workers at the Department of Veterans Affairs (VA) health care system in the U.S. South? We needed to explore these questions to formulate knowledge that could be beneficial for VA health care. This literature review assesses the current responses from the field of social work during the COVID-19 pandemic, leveraging telemedicine, social work self-care, and the fluidity of VA services.
Several explanations have been advanced to account for the apparent diurnal variation in crop hydraulic resistance (Rp) calculated from a simple Ohm's Law analog. In this paper, we suggest that Rp, ...calculated in this way, may vary because of spatial variation in soil water potential. We propose that whenever transpiration rate (Q) is small and leaf water potential is relatively high, roots extract water mainly from those regions of the soil profile where soil water potential is also high (usually deep in the profile). As Q increases and leaf water potential becomes more negative, roots begin removing water from regions of the profile where soil water potential is more negative. Hence the length of roots actually taking up water at a particular time, and therefore Rp, may vary diurnally. Also, variations in soil water potential and rooting density often make the relation between leaf water potential and water uptake rate unique for each soil region. So, even when all roots are taking up water, leaf water potential and the aggregated uptake rate may be nonlinearly related, and Rp will vary diurnally with leaf water potential. This theory is illustrated with exploratory calculations of Rp for hypothetical temperate cereal crops grown in three different soils (a clay, a silt loam, and a sandy loam), with various combinations of root system properties and evapotranspiration rates. Crop water content and root radial resistivity were assumed constant. Although soil waterpotential was initially distributed uniformly in these simulations, heterogeneity in root distribution soon caused spatial variation in soil water potential and Rp showed marked diurnal variations. Variation in Rp increased with the predicted variation in soil water potential. Detailed field experiments and simulation analyses are needed to quantitatively compare this and other hypotheses to explain diurnal variation in Rp.
A superconducting magnet system for the J-PARC neutrino beam line has been under construction since 2004. The system consists of 14 doublet cryostats; each contains 2 combined function magnets ...(SCFM). The SCFM uses two single layer left/right asymmetric coils that produce a dipole field of 2.6 T and quadrupole of 19 T/m. The SCFMs had been developed by 2004, mass-produced since 2005, and completed by summer 2008. The system is being installed since Feb. 2008 till the end of 2008. The paper summarizes the system overview including cryogenics and safety peripheries. The paper also reports the production and installation status.
A study was conducted to investigate the effect of selective catalytic reduction (SCR) catalyst on mercury (Hg) speciation in bituminous and subbituminous coal combustion flue gases. Three different ...Illinois Basin bituminous coals (from high to low sulfur S and chlorine Cl) and one Powder River Basin (PRB) subbituminous coal with very low S and very low Cl were tested in a pilot-scale combustor equipped with an SCR reactor for controlling nitrogen oxides (NO
x
) emissions. The SCR catalyst induced high oxidation of elemental Hg (Hg
0
), decreasing the percentage of Hg
0
at the outlet of the SCR to values <12% for the three Illinois coal tests. The PRB coal test indicated a low oxidation of Hg
0
by the SCR catalyst, with the percentage of Hg
0
decreasing from ∼96% at the inlet of the reactor to ∼80% at the outlet. The low Cl content of the PRB coal and corresponding low level of available flue gas Cl species were believed to be responsible for low SCR Hg oxidation for this coal type. The test results indicated a strong effect of coal type on the extent of Hg oxidation.
Since drug candidates with low oral systemic exposure may be due to either or both absorption and metabolism factors, determining what factors limit the oral systemic exposure is not always obvious ...in a single in-vivo pharmacokinetic (PK) assay. A rapid rat in-vivo PK screen where the oxidative drug metabolism has been attenuated using the suicide CYP450 inhibitor aminobenzotriazole (ABT) is described. We have shown that the roles of absorption and metabolism for drug candidates with low oral systemic exposure can be determined by comparing the PK parameters of drug candidates orally administered to non-treated and ABT-treated rats. Propranolol, metoprolol and climetidine are used as model drugs. Propranolol and metoprolol have low oral systemic exposures in rats primarily due to metabolism factors while the oral systemic exposure of climetidine is high in rats. For propranolol and metoprolol, large increases in the systemic exposure of these drugs were observed between non-treated and ABT-treated rats. ABT appeared not to increase or decrease significantly the rate and extent of absorption or metabolism of cimetidine since that oral systemic exposure of non-treated and ABT-treated rats did not significantly change. These experiments suggest that for drug candidates with low systemic exposures in rats an observation of no change in the oral systemic exposure in ABT-treated rats when compared to the non-treated rats imply that absorption (or formulation) factors limit the systemic exposure of the drug while an increase in the systemic exposure in ABT-treated rats imply that metabolism factors limit the systemic exposure. Due to the ease of preparing and interpreting PK data from ABT-treated rats, is suggested that this assay could be used as an alternative to in vivo cannulation assays.
The fouling from whey protein concentrate (WPC) and milk in a plate heat exchanger (PHE) are compared. Significant differences were seen in the intermediate sections, where WPC causes extensive ...fouling and milk causes none. The morphology of deposits was studied using SEM and Elemental Mapping and compositional analysis of surface deposits was examined. For both fluids, fouling in the pasteurization section of the PHE was found to be mostly aggregated protein. However, as temperature increased, deposits from milk changed to be mainly mineral, whereas WPC caused protein deposits right up to UHT temperatures. (Original abstract - amended)
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