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71.
Abstract

The objective was to assess whether job insecurity and fear of litigation were correlates of depression, anxiety, and stress among expatriate nurses in Saudi Arabia. The participants included 977 expatriate nurses working in Al-Qassim, Saudi Arabia who completed an online survey that assessed depression, anxiety, and stress (using DASS-21) as well as demography, lifestyle, and job characteristics. Mean age was 32?years and 60% of nurses were from India/Pakistan. Twenty-four percent of nurses reported job insecurity, and 18% reported a fear of litigation. Severe depression, anxiety, and stress were significantly higher among nurses who always felt insecure about their job (compared to never) and among those who always feared litigation (compared to never). We concluded that job insecurity and fear of litigation were significant correlates of severe depression, anxiety, and stress among expatriate nurses.  相似文献   
72.
The deposition of thin layers of polymer/ceramic on a lithium surface to produce a strong barrier against dendrites was demonstrated. Different forms (needle, sphere, rod) and types of ceramic (Al2O3, Mg2B2O5) were tested and polymer/ceramic interlayers of a few micrometers (4 μm minimum) between the lithium and the PEO-based solid polymer electrolyte (SPE) were deposited. Interlayers with high amounts of ceramic up to 85 wt% were successfully coated on the surface of lithium foil. Compact “polymer in ceramic” layers were observed when Al2O3 spheres were used for instance, providing a strong barrier against the progression of dendrites as well as a buffer layer to alleviate the lithium deformation during stripping/plating cycles. The electrochemical performance of the lithium anodes was assessed in symmetrical Li/SPE/Li cells and in full all-solid-state LiFePO4 (LFP)/SPE/Li batteries. It was observed for all the cells that the charge transfer resistance was significantly reduced after the deposition of the polymer/ceramic layers on the lithium surface. In addition, the symmetrical cells were able to cycle at higher C-rates and the durability at C/4 was even improved by a factor of 8. Microscopic observations of Li/SPE/Li stacks after cycling revealed that the polymer/ceramic interlayer reduces the deformation of lithium upon cycling and avoids the formation of dendrites. Finally, LFP/SPE/Li batteries were cycled and better coulombic efficiencies as well as capacity retentions were obtained with the modified lithium electrodes. This work is patent-pending (WO2021/159209A1).

Significant electrochemical performance improvement of symmetric Li/Li polymer cells at C/4 by using ceramic-rich coated lithium anodes.  相似文献   
73.
The determinants of frequent visits to the emergency department (ED) for asthma were evaluated in 30 patients who made 2 or more ED visits for asthma (mean, 3.1; range, 2 to 9) over a period of 1 year. They were matched for age, sex, and medication with a control group of asthmatic patients who had made no ED visits within the same period. Evaluation included measurements of expiratory flows (baseline FEV1; PEFR 4 times daily for 3 weeks), airway responsiveness to methacholine, perception of induced bronchoconstriction, and questionnaires on quality of life and knowledge of asthma and its management. In comparison with the control group, the study group showed a trend toward inferior socioeconomic status, education level, and technical abilities (eg, inhaler use). Both groups had similar baseline FEV1, reversibility of airflow obstruction, methacholine-induced changes in expiratory flows, and perception of bronchoconstriction. Diurnal variation in PEFR was slightly increased in the study group. Absenteeism from work or school was higher in the study group but quality of life score was similar to controls. Patients with frequent ED visits showed significantly lesser knowledge of asthma control criteria, as well as an overall trend toward reduced asthma management knowledge and skills. In conclusion, in addition to the previously reported undertreatment of asthma, other factors such as insufficient asthma management knowledge and skills may contribute to frequent ED visits for asthma.  相似文献   
74.
75.
Studies examining the role of PD‐1 family members in allergic asthma have yielded conflicting results. Using a mouse model of allergic asthma, we demonstrate that blockade of PD‐1/PD‐L1 has distinct influences on different CD4+ T‐cell subsets. PD‐1/PD‐L1 blockade enhances airway hyperreactivity (AHR), not by altering the magnitude of the underlying Th2‐type immune response, but by allowing the development of a concomitant Th17‐type immune response. Supporting differential CD4+ T‐cell responsiveness to PD‐1‐mediated inhibition, naïve PD‐1?/? mice displayed elevated Th1 and Th17 levels, but diminished Th2 cytokine levels, and ligation of PD‐1 in WT cells limited cytokine production by in vitro polarized Th1 and Th17 cells, but slightly enhanced cytokine production by in vitro polarized Th2 cells. Furthermore, PD‐1 ligation enhanced Th2 cytokine production by naïve T cells cultured under nonpolarizing conditions. These data demonstrate that different CD4+ T‐cell subsets respond differentially to PD‐1 ligation and may explain some of the variable results observed in control of allergic asthma by the PD‐1 family members. As the PD‐1/PD‐L1 axis limits asthma severity by constraining Th17 cell activity, this suggests that severe allergic asthma may be associated with a defective PD‐1/PD‐L1 regulatory axis in some individuals.  相似文献   
76.
PURPOSE: Functional mapping of eloquent cortex with electrical neurostimulation is used both intra- and extraoperatively to tailor resections. In pediatric patients, however, functional mapping studies frequently fail to localize language. Wada testing has also been reported to be less sensitive in children. METHODS: Thirty children (4.7 - 14.9 years) and 18 adult controls (18-59 years) who underwent extraoperative language mapping via implanted subdural electrodes at the NYU Comprehensive Epilepsy Center were included in the study. Ten children and 14 adults underwent preoperative Wada testing. Success of the procedures was defined as the identification of at least one language site by neurostimulation mapping and determination of hemispheric language dominance on the Wada test. RESULTS: In children younger than 10.2 years, cortical stimulation identified language cortex at a lower rate than was seen in children older than 10.2 years and in adults (p<0.05). This threshold, demonstrated by survival and chi2 analysis, was sharply defined in our data set. Additionally, Wada testing was more likely to be successful than was extraoperative mapping in this younger age group (p<0.05). CONCLUSIONS: Analysis of our series demonstrates that language cortex is less likely to be identified in children younger than 10 years, suggesting that alternatives to the current methods of cortical electrical stimulation, particularly the use of preoperative language lateralization, may be required in this age group.  相似文献   
77.
BACKGROUND: In the fall 2005, approximately 7,500 US military personnel participated in an exercise in the Egyptian desert. The epidemiology of disease and noncombat injury among deployed troops is important in the context of assessing current mitigation strategies and the development of future ones. METHODS: To assess the prevalence and impact of diarrhea and enteropathogen distribution, we conducted a case series study. To assess the relative impact of diarrhea compared to respiratory infection and injury, we conducted a post-deployment survey and compared these data to clinic-based syndromic surveillance data. RESULTS: We enrolled 43 patients with acute diarrhea, 21 (49%) having one or more pathogens isolated. Enterotoxigenic Escherichia coli (n= 16), enteroaggregative E coli (n= 3), and Shigella spp. (n= 3) were the most common pathogens identified. Respiratory illness had the highest incidence (73 episodes/100 person-months) compared to diarrhea (35 episodes/100 person-months) and noncombat injury (17 episodes/100 person-months), though noncombat injury more frequently resulted in lost duty days and health-care utilization. CONCLUSIONS: Noncombat injuries and illnesses have had a significant impact on military missions and continue to result in force health protection challenges today. Future studies are needed to test and evaluate countermeasures to mitigate these illnesses and injuries to increase the health of the individuals and optimize mission readiness.  相似文献   
78.
79.
Energy transfer processes between beta carotene, lycopene, and singlet oxygen ((1)O(2)) have been studied by ultrafast Raman spectroscopy. Our experimental results demonstrate that during the neutralization of singlet oxygen by beta carotene the excitation energy of singlet oxygen is transferred directly to the first excited electronic state S(1) of beta carotene. In contrast, the excitation energy of singlet oxygen is transferred directly to the ground excited vibronic state S(0) of lycopene. Our data not only provide the first direct experimental elucidation of energy transfer processes in such important biological systems but also help explain why lycopene is a more potent antioxidant than beta carotene in the neutralization of singlet oxygen.  相似文献   
80.
BACKGROUND AND PURPOSE: Performing nontraditional abdominal exercises with devices such as abdominal straps, the Power Wheel, and the Ab Revolutionizer has been suggested as a way to activate abdominal and extraneous (nonabdominal) musculature as effectively as more traditional abdominal exercises, such as the crunch and bent-knee sit-up. The purpose of this study was to test the effectiveness of traditional and nontraditional abdominal exercises in activating abdominal and extraneous musculature. SUBJECTS: Twenty-one men and women who were healthy and between 23 and 43 years of age were recruited for this study. METHODS: Surface electromyography (EMG) was used to assess muscle activity from the upper and lower rectus abdominis, external and internal oblique, rectus femoris, latissimus dorsi, and lumbar paraspinal muscles while each exercise was performed. The EMG data were normalized to maximum voluntary muscle contractions. Differences in muscle activity were assessed by a 1-way, repeated-measures analysis of variance. RESULTS: Upper and lower rectus abdominis, internal oblique, and latissimus dorsi muscle EMG activity were highest for the Power Wheel (pike, knee-up, and roll-out), hanging knee-up with straps, and reverse crunch inclined 30 degrees. External oblique muscle EMG activity was highest for the Power Wheel (pike, knee-up, and roll-out) and hanging knee-up with straps. Rectus femoris muscle EMG activity was highest for the Power Wheel (pike and knee-up), reverse crunch inclined 30 degrees, and bent-knee sit-up. Lumbar paraspinal muscle EMG activity was low and similar among exercises. DISCUSSION AND CONCLUSION: The Power Wheel (pike, knee-up, and roll-out), hanging knee-up with straps, and reverse crunch inclined 30 degrees not only were the most effective exercises in activating abdominal musculature but also were the most effective in activating extraneous musculature. The relatively high rectus femoris muscle activity obtained with the Power Wheel (pike and knee-up), reverse crunch inclined 30 degrees, and bent-knee sit-up may be problematic for some people with low back problems.  相似文献   
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