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91.
In the present study, we adopt an easy and cost-effective route for preparing Cu2ZnSnS4 (CZTS)-absorber nanoparticles by a mechanochemical method using non-toxic and environmentally benign solvents (butanol, methyl ethyl ketone, and ethanol). The gram-scale synthesis of absorber nanoparticles was achieved in a non-hazardous, zero-waste process without using high-vacuum equipment. The effects of annealing and Na incorporation on the properties of spin-coated CZTS thin films were scrutinized. The deposited samples showed kesterite crystal structure and single phase. The morphological results revealed an improvement in the surface morphology after annealing. The optical bandgaps of the thin films lied in the range of 1.50–1.57 eV with p-type nature. Finally, photovoltaic devices were fabricated, and their cell performance parameters were studied. An efficiency of 0.16% was observed. The present study provides a potential route for the cost-effective fabrication of CZTS-based photovoltaic devices.  相似文献   
92.
To improve the management of soldiers with combat-related mental health problems, an interdisciplinary telepsychiatry service was established between a clinic at the Fort Bragg army base and the Veterans Affairs (VA) Medical Center in Salem. In the first 12 months of operation, 120 soldiers (105 males) were seen in a total of 394 telepsychiatry sessions. The time spent on telepsychiatry by the six VA psychiatrists increased from 13 hours in the first month to 41 hours in the twelfth month. The number of telepsychiatry sessions increased from nine in the first month to 56 in the twelfth month. The mean global assessment of function score (GAF) in the soldiers increased significantly (P < 0.001) from 58.0 at intake to 62.3 at the last visit. Soldiers received VA telepsychiatry on average 22 days after the initial consultation with a primary care provider, a reduction of at least eight days compared to the previous delay. The majority of soldiers (89%) who were treated by VA psychiatrists enrolled in the VA within about six months of discharge. Similar VA-US Military collaborations may prove beneficial for other military bases that have returning combat soldiers.  相似文献   
93.
94.
Three new series of quinoline-4-yl-1,2,3-triazoles carrying amides, sulphonamides and amidopiperazines were synthesized through multi-step reactions. The required intermediate, [1-(6-methoxy-2-methylquinolin-4-yl)-1H-1,2,3-triazol-4-yl]methanol (2) was prepared by treating 4-azido-6-methoxy-2-methylquinoline (1) with propargyl alcohol. Three different series of compounds were synthesized from this intermediate. All the newly synthesized compounds were characterized by spectral and elemental analyses. The structure of 2 was confirmed by X-ray crystallographic study. Further, the title compounds were evaluated for their in vitro anti-bacterial activity against five different bacterial strains and antimycobacterial activity against Mycobacterium tuberculosis H37Rv, Mycobacterium smegmatis (ATCC 19420) and Mycobacterium fortuitum (ATCC 19542). Title compounds, 6a, 6d, 6i, 6j, 7e, 10a and 10i were found to be active against Mycobacterium tuberculosis H37Rv strain and could be lead molecules of interest.  相似文献   
95.
Prostate cancer (PCa) is a major lethal malignancy in men, but the molecular events and their interplay underlying prostate carcinogenesis remain poorly understood. Epigenetic events and the upregulation of polycomb group silencing proteins including Bmi1 have been described to occur during PCa progression. Here, we found that conditional overexpression of Bmi1 in mice induced prostatic intraepithelial neoplasia, and elicited invasive adenocarcinoma when combined with PTEN haploinsufficiency. In addition, Bmi1 and the PI3K/Akt pathway were coactivated in a substantial fraction of human high-grade tumors. We found that Akt mediated Bmi1 phosphorylation, enhancing its oncogenic potential in an Ink4a/Arf-independent manner. This process also modulated the DNA damage response and affected genomic stability. Together, our findings demonstrate the etiological role of Bmi1 in PCa, unravel an oncogenic collaboration between Bmi1 and the PI3K/Akt pathway, and provide mechanistic insights into the modulation of Bmi1 function by phosphorylation during prostate carcinogenesis.  相似文献   
96.
In India, very few reports on the cost of adverse drug reactions (ADRs) are available. There is a need to study this aspect of health care in order to understand the economic burden imposed by ADRs. The aim of the current work was to study the costs associated with documented ADRs in a tertiary care teaching hospital. This study was conducted in medical wards of a south Indian tertiary care teaching hospital over a 6-month period. The study protocol was assessed and approved by the institutional ethics committee. A total of 317 ADRs from 246 patients were identified during the study period. The present study used an intensive monitoring method to detect ADRs and assessed an incidence of 32.7% adverse reactions in the monitored group. The causality, severity, predictability, and preventability of the documented ADRs were assessed. The total cost to the hospital due to ADRs was found to be Rs. 1,567,397 (US$36 451). The average cost per patient hospitalized with an ADR was Rs. 4,945 (US$115). The cost per reaction was found to be higher in the Indian context, as the per capita annual expenditure on health in this country is around US$109.  相似文献   
97.
Retinal ganglion cells comprise about 10 morphological types that also differ functionally. To determine whether functional differences might arise partially from differences in excitatory input, we quantified the distributions of ribbon contacts to four mammalian ganglion cell types [brisk-transient (BT), brisk-sustained (BS), local edge (LE), directionally selective (DS)], comparing small vs. large and "sluggish" vs. "brisk." Cells in guinea pig retina were filled with fluorescent dye, immunostained for synaptic ribbons, and reconstructed with their ribbon contacts by confocal microscopy. False-positive contacts were corrected by performing the same analysis on processes that lack synapses: glial stalks and rod bipolar axons. All types shared a domed distribution of membrane that was well fit by a Gaussian function (R(2) = 0.96 +/- 0.01); they also shared a constant density of contacts on the dendritic membrane, both across each arbor and across cell types (19 +/- 1 contacts/100 microm(2) membrane). However, the distributions of membrane across the retina differed markedly in width (BT > DS approximately BS > LE) and peak density (BS > DS > LE > BT). Correspondingly, types differed in peak density of contacts (BS > DS approximately LE > BT) and total number (BS approximately BT > DS > LE). These differences between cell types in spatial extent and local concentration of membrane and synapses help to explain certain functional differences.  相似文献   
98.
Ancient literature mentions the use of a number of plants/preparationsfor fertility regulation. Some local contraceptive agents havealso been described in Ayurvedic and Unani texts. Documentedexperiments or clinical data are, however, lacking. Therefore,the present study was undertaken to explore the antifertilityand estrogenic activity of ethanolic extract of the roots ofHibiscus rosa-sinensis Linn. A strong anti-implantation (inhibition100%) and uterotropic activity was observed at the dose levelof 400 mg/kg body weight. Histological studies were carriedout to confirm this effect.  相似文献   
99.
100.
Objective:To evaluate and compare the root surface morphological changes after 980-nm diode laser–aided circumferential supracrestal fiberotomy (CSF) on fluorosed and non-fluorosed teeth.Materials and Methods:The sample comprised 27 orthodontic patients (14 males and 13 females; mean age  =  17.3 years) with and without fluorosis, from whom 40 fluorosed and 40 non-fluorosed premolar teeth were extracted for orthodontic reasons. Conventional (control group) and laser-aided (experimental group) CSF was performed on fluorosed and non-fluorosed teeth indicated for orthodontic extraction, using a scalpel and a 980-nm diode laser at 2.5 W power, respectively. Subsequently, teeth were extracted, sectioned, and examined by scanning electron microscope to assess the ultrastructural changes.Results:There were differences in surface morphology among fluorosed and non-fluorosed roots in the control group. The root specimens of both fluorosed and non-fluorosed teeth irradiated by diode laser exhibited no evidence of smear layer, laser-induced pitting or cavitation, linear cuts/markings, carbonization of surface, and heat-induced surface cracking. However, a glazed or slightly melted appearance was observed in root specimens of fluorosed teeth after diode laser irradiation.Conclusions:These findings suggest that the diode laser–aided CSF procedure is free from thermal hazard on non-fluorosed root surfaces but may provoke some thermal changes on fluorosed root surfaces.  相似文献   
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