Beringvance0941

An efficient surface defect passivation is observed by reacting clean Si in a dilute hydrogen sulfide-argon gas mixture ( less then 5% H2S in Ar) for both n-type and p-type Si wafers with planar and textured surfaces. Surface recombination velocities of 1.5 and 8 cm s-1are achieved on n-type and p-type Si wafers, respectively, at an optimum reaction temperature of 550 °C that are comparable to the best surface passivation quality used in high efficiency Si solar cells. Surface chemical analysis using x-ray photoelectron spectroscopy shows that sulfur is primarily bonded in a sulfide environment, and synchrotron-based soft x-ray emission spectroscopy of the adsorbed sulfur atoms suggests the formation of S-Si bonds. The sulfur surface passivation layer is unstable in air, attributed to surface oxide formation and a simultaneous decrease of sulfide bonds. However, the passivation can be stabilized by a low-temperature (300 °C) deposited amorphous silicon nitride (a-SiNXH) capping layer.Liquid cell electron microscopy is an imaging technique allowing for the investigation of the interaction of liquids and solids at nanoscopic length scales. Suchin situobservations are increasingly in-demand in an array of fields, from biological sciences to medicine to batteries. Graphene liquid cells (GLCs), in particular, have generated a great interest as a low-scattering window material with the potential for increasing the quality of both imaging and spectroscopy. However, preserving the stability of the liquid and of the sample in the GLC remains a considerable challenge. In the present work we encapsulate water and hydroxyapatite (HAP), a pH-sensitive biological material, in GLCs to observe the interactions between the graphene, HAP, and the electron beam. HAP was chosen for several reasons. One is its ubiquity in biological specimens such as bones and teeth, and the second is the presence of phosphate ions in common buffer solutions. Finally, there is its sensitivity to changes in pH, which result fring and the available imaging time, as well as avoiding the beam-induced artifacts.A defects-enriched CoMoO4/CD with CoMoO4 around 37 nm is achieved via hydrothermal reaction by introducing carbon dots (CDs) to buffer large volume changes of CoMoO4 during lithiation-delithiation and enhance rate performance. The phase, morphology, microstructure, as well as the interface of the CoMoO4/CD composites were investigated by XRD, SEM, TEM and XPS. When employed as Li-ion battery anode, the CoMoO4/CD exhibits a reversible capacity of ~531 mAh g-1 after 400 cycles at a current density of 2.0 A g-1. Under the scan rate at 2 mV s-1, the CoMoO4/CD shows accounts for 81.1% pseudocapacitance. It may attribute to the CoMoO4 with surface defects given more reaction sites to facilitate electrons and lithium ions transfer at high current densities. Through GITT, the average lithium ion diffusion coefficient calculated is an order of magnitude larger than that of bulk CoMoO4, indicating that the CoMoO4/CD possesses promising electrons and lithium ions transportation performance as anode material.Cell culture systems are indispensablein vitrotools for biomedical research. Although conventional two-dimensional (2D) cell cultures are still used for most biomedical and biological studies, the three-dimensional (3D) cell culture technology attracts increasing attention from researchers, especially in cancer and stem cell research. Due to the different spatial structures, cells in 2D and 3D cultures exhibit different biochemical and biophysical phenotypes. Therefore, a new platform with both 2D and 3D cell cultures is needed to bridge the gap between 2D and 3D cell-based assays. Here, a simultaneous 2D and 3D cell culture array system was constructed by microprinting technology, in which cancer cells exhibited heterozygous geometry structures with both 2D monolayers and 3D spheroids. Cells grown in 3D spheroids showed higher proliferation ability and stronger cell-cell adhesion. Spheroids derived from various types of cancer cell lines exhibited distinct morphologies through a geometrical confinement stimucell detection.MoSi2is widely concerned due to excellent electrical conductivity, oxidation resistance as a typical transition metal silicide. The high-temperature diffusion behavior is one of the important factors for the degradation of MoSi2coatings. However, the diffusion mechanism in MoSi2is still unclear. Liproxstatin-1 cost Prior theoretical work mostly focused on defect formation energy, but these are not consistent with the self-diffusion experiments because the migration behaviors were not considered. Therefore, the purpose of this work was to investigate the microscopic diffusion mechanisms of Mo and Si atoms in MoSi2using density functional theory and the CI-NEB method. We confirmed that the temperature-dependent vibrational contribution has a significant impact on the defect formation free energy. The isolated point defects in MoSi2will tend to aggregate to form defect complexes, which participate in the atomic diffusion as mediators. The defect migration behaviors of atoms for vacancy mediated, vacancy complex mediated, and antisite assisted jumps were obtained based on electronic structures analysis. The results show that Si diffusion is mediated by intrasublattice jumps of the nearest neighbor Si vacancies. Moreover, the destroyed covalent Mo-Si bonds by Si vacancies and the non-directional weak metal bonds formed by the Mo antisites and Mo atoms could improve the mobility of the Mo atom which results in the low migration barrier. The agreement between our calculations and the reported experimental results indicates that the dominant diffusion mechanism for Mo atoms is mediated by vacancy complex mediated jumps and antisite assisted jumps. It is concluded that the Si vacancy-based defect complexes are likely the diffusion mediators for Mo atom self-diffusion in MoSi2. This work provides a deeper insight into the connection between the atomic mechanism and the macroscopic behavior for the diffusion in the MoSi2, and establishes the basis for further optimizing high-temperature coating materials.

Exercise performed at home could be a useful therapy for people with chronic kidney disease. This systematic review and meta-analysis aimed at describing the characteristics, main findings, methodological quality, and adherence rate reported in the existent randomized controlled trials that have provided information regarding the impact of home-based exercise programs on people with chronic kidney disease.

Electronic databases (MEDLINE/PubMed, SPORTDiscus, Scopus, and CENTRAL) were searched up to April 2021, using the keywords "Exercise"; "Home"; "Kidney Disease." Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement was adopted. link2 Jadad scale and Cochrane's tool were used to assess the methodological quality and risk of bias.

Out of the 14 studies finally selected, 11 were included in the meta-analysis and most presented high methodological quality. The meta-analysis showed significant effects of home-based exercise on fitness and quality of life, but a little impact on renal function. Although exercise performed at home was mostly feasible and safe, adherence was not high and a considerable number of dropouts were observed.

Home-based exercise has positive effects on the fitness' level and on the quality of life on people with chronic kidney disease. Future studies are needed to identify whether exercise performed at home is a better physical therapy option than center-based exercise.

Home-based exercise has positive effects on the fitness' level and on the quality of life on people with chronic kidney disease. Future studies are needed to identify whether exercise performed at home is a better physical therapy option than center-based exercise.

This study analyzed whether self-efficacy (SE) and perceived environmental characteristics (EC) are determinants of the decline in physical activity (PA) time in adolescents.

This used longitudinal observational approach, with 4 years of data collection, involving 355 adolescents (57.7% girls and 42.3% boys), average age of 11.8 years (0.1y), from João Pessoa, Paraiba, Brazil. link3 SE and EC were measured by scales and PA by a questionnaire. Ordinal logistic regression was used to associate SE and EC with a decline in PA.

There was a linear trend toward a decrease in average PA duration (58.3 [13.7]min/wk/y) and a rise in average access to places for PA (point per year) (0.6 [0.1]), urban safety (0.2 [0.1]), and traffic safety scores (0.5 [0.1]). The results of multivariable analysis indicated that SE and EC were not associated with the decline in PA.

There was a decline in PA time, and SE and perceived EC were not determinants of this decline.

There was a decline in PA time, and SE and perceived EC were not determinants of this decline.

Choose to Move is one of few scaled-up health-promoting interventions for older adults. The authors evaluated whether Choose to Move participants maintained their intervention-related gains in physical activity (PA), mobility, and social connectedness 12 months after the intervention ended.

The authors assessed PA, mobility, loneliness, social isolation, and muscle strength via questionnaire and objective measures in 235 older adults at 0 months (baseline), 6 months (end of intervention), and 18 months (12-months postintervention). The authors fitted linear mixed models to examine the change in each outcome from 6 to 18 months (primary objective) and 0 to 18 months (secondary objective) and reported by age group (60-74 and ≥75 y).

In younger participants, PA decreased between 6 and 18 months, but remained significantly higher than at baseline. Intervention-related benefits in loneliness, social isolation, mobility, and muscle strength were maintained between 6 and 18 months in the younger participants. Older participants maintained their intervention benefits in loneliness, mobility, and muscle strength. When compared with baseline values, PA levels in older participants were unchanged, whereas social isolation increased.

Older adults maintained some, but not all, health benefits of Choose to Move 12 months after the intervention ended. Long-term commitments are needed to deliver effective health-promoting interventions for older adults if benefits are to be maintained.

Older adults maintained some, but not all, health benefits of Choose to Move 12 months after the intervention ended. Long-term commitments are needed to deliver effective health-promoting interventions for older adults if benefits are to be maintained.Although physical activity (PA) is an important determinant of exercise capacity, the association between these constructs is modest. The authors investigated the associations of self-reported and objectively measured PA with maximal and submaximal tests of exercise capacity. Participants aged ≥40 years (N = 413; 49.6% female) completed a PA questionnaire, wore a uniaxial accelerometer (5.2 ± 1.1 days), and performed maximal (cardiopulmonary exercise test [CPET]) and submaximal (long-distance corridor walk) tests with indirect calorimetry (oxygen consumption, V˙O2). Linear regression models were fitted to assess the variation in exercise capacity explained (partial eta squared, η2) by PA variables. Accelerometer-measured vigorous (η2 = 22% female; η2 = 16% male) and total PA (η2 = 17% female; η2 = 13% male) explained the most variance in CPET V˙O2 (p less then .001). All η2 values were lower for long-distance corridor walk V˙O2 (η2 ≤ 11%). Age contributed more to CPET V˙O2 than any PA variable in males (η2 = 32%), but not in females (η2 = 19%).