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81.
Wireless Personal Communications - Wireless sensor networks (WSNs) find their application in as diverse fields as collection of data for weather forecasting to detection of enemy activities by...  相似文献   
82.
BACKGROUND: Fresh vegetable produce is abundant during the winter season in Punjab. It is an important source of vitamins and minerals in the Punjabi diet, but the availability of ascorbic acid and beta-carotene from the vegetables is altered to varying degrees when they are subjected to traditional household processing methods. OBJECTIVE: To determine the importance of traditional cooked vegetable dishes as sources of ascorbic acid and beta-carotene among urban and rural families during the winter. METHODS: Information about vegetable consumption, storage, and cooking practices was collected from 60 families, 30 each from urban and rural areas of Ludhiana District, Punjab, India. Samples of the common cooked vegetable dishes were prepared in the laboratory by methods ascertained from the survey and analyzed for ascorbic acid and beta-carotene. RESULTS: The average total daily per capita consumption of vegetables by urban and rural families was 411.7 and 365.9 g, respectively. Cooked vegetable dishes provided 68.7% of the total vegetable intake for urban families and 85.0% for rural families. On average, the edible portion constituted 78.9% of the weight of the vegetables. Ten cooked vegetable dishes that were most frequently consumed by the families (mustard saag, potato-spinach, potato-fenugreek, potato-brinjal, potato-cauliflower, potato-capsicum, potato-carrots, potato-beans, potato-peas, and cabbage-peas) were selected for preparation in the laboratory and nutritional analysis. The average concentrations of ascorbic acid and beta-carotene in the cooked vegetable dishes were 46.0 mg/100 g and 794.2 microg/100 g fresh weight, respectively. The percentage losses of ascorbic acid and beta-carotene during preparation and cooking were 26.1% and 25.9%, respectively. CONCLUSIONS: For adult Indian men and women, the recommended dietary allowance of ascorbic acid is 40 mg, and that of beta-carotene is 2,400 microg. Cooked vegetable dishes provided 269.9% and 77.5% of the recommended dietary allowances of ascorbic acid and beta-carotene, respectively, indicating that these dishes are good sources of these nutrients in the diets of both urban and rural families during the winter season.  相似文献   
83.
New poly(vinylidene fluoride) (PVDF)/NiO-based polymer nanocomposites were prepared by phase inversion method, using dimethyl formamide as solvent and deionized water as non-solvent. The structure and porous morphology of the membranes were studied by field emission scanning electron microscopy. The presence of NiO resulted in overall decrease in porosity and crystallinity of the nanocomposite membranes. Using electrochemical impedance spectroscopy, a maximum ionic conductivity of 1.08 × 10−3 S cm−1 was obtained for PVDF membrane with 1 wt% content of NiO. The good efficiency of conductivity observed in the membrane was explained on the basis of decrease in crystallinity and movement of charge carriers in NiO structure. The magnetization of nanocomposite membranes gradually increased with increase in NiO content.  相似文献   
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PURPOSE: To determine whether esophagography with use of barium alone is safe for detection of postoperative leaks of the esophagus. MATERIALS AND METHODS: A review was performed of 29 postoperative esophagograms that showed 29 leaks in 12 patients. All studies were performed with a 50% dilution of barium sulfate. Leak volumes were calculated as the product (in cubic centimeters) of the length, width, and height. The safety and efficacy of barium were determined on the basis of development of mediastinitis and retention of barium in the mediastinum that would interfere with subsequent patient care. RESULTS: In 11 of the 12 patients, follow-up studies were performed 4-48 days (mean, 10.2 days) after diagnosis. Leaks were 0.25-375 cm3 (mean, 31.4 cm3). In five of 17 (29%) follow-up procedures, small amounts of residual barium were detectable on the scout radiograph, none of which interfered with interpretation of the new images. During a follow-up period of 7-448 days (mean, 226 days), no cases of mediastinitis were found. CONCLUSION: Esophagography can be performed safely with barium to rule out an anastomotic esophageal leak.  相似文献   
87.
Electrical stimulation in the subfornical organ (SFO) of male Sprague-Dawley rats resulted in biphasic increases in blood pressure (BP) without a change in heart rate. The initial short duration (0-10 s) increase in BP lasted throughout the 10 s stimulation period (area under the curve (AUC) = 104.3+/-15.26 mmHg/s, (mean+/-SEM) P < 0.001). Upon termination of the electrical stimulus, the BP remained elevated for approximately 55 s (long duration response, AUC = 327.5+/-48.22 mmHg/s, P < 0.001). This long duration BP response was determined to be the result of an increase in circulating vasopressin (VP) as administration of a V1 receptor antagonist abolished this response (AUC = -210.7 +/- 42.38 mmHg/s, P < 0.01). The results of the present study demonstrate that the long duration component of the biphasic increase in BP observed on response to electrical stimulation of the SFO is the result of increased concentrations of circulating VP.  相似文献   
88.
Pseudoexfoliation (PEX) syndrome is the commonest identifiable cause of open-angle glaucoma worldwide. PEX is characterized clinically by small whitish deposits of fibrillar-granular material in the anterior segment of the eye. Despite its prevalence and potential for ophthalmic morbidity, surprisingly little is known about the etiology and pathogenesis of PEX. This article reviews the literature and presents evidence regarding genetic and nongenetic arguments for the etiology of pseudoexfoliation. Lines of evidence that support a genetic basis for PEX include transmission in two-generation families, twin studies, an increased risk of PEX in relatives of affected patients, and HLA studies. Nearly all pedigrees in the literature, and our own experience with PEX families in Iceland and Canada, suggest maternal transmission, raising the possibilities of mitochondrial inheritance, X-linked inheritance, and autosomal inheritance with genomic imprinting. A number of nongenetic factors have also been evaluated for their possible implication in the development of PEX. These include ultraviolet light, autoimmunity, slow virus infection, and trauma. It is possible that a combination of genetic and nongenetic factors may be involved in the etiology and pathogenesis of PEX, i.e. it may be a multifactorial disorder. Further studies with larger numbers of patients are needed to delineate more clearly the contribution of genetic (nuclear DNA, mitochondrial DNA or both) and nongenetic factors to the development of pseudoexfoliation syndrome and pseudoexfoliation glaucoma.  相似文献   
89.
Psychotherapists lack clear guidelines regarding how to address clients’ racist and prejudicial comments in clinical work. The authors explore the contributions of multicultural, social justice, feminist, and ethical theories to the field of psychotherapy and apply these theories to 2 clinical vignettes in which clients made racially charged statements. These clinical examples highlight the importance of using racial, in addition to traditional, theories to decipher the clinical meanings of racial comments and dynamics in clinical work. The article provides therapeutic conceptualizations regarding how to address clients’ racist and prejudicial comments in psychotherapy and elaborates on the complex meanings that might arise from engaging in racially charged discussions with clients depending on the racial composition of the therapeutic dyad. In addition to highlighting how social justice, multicultural, and feminist lenses are necessary to fully understand the meaning of clients’ comments, the argument is made that addressing clients’ racist and prejudicial comments is at once a clinical and a social justice issue. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
90.
An efficient microwave-assisted route has been used to synthesize nanoparticles of cobalt oxide. The particles were well characterized by transmission electron microscopy (TEM) which showed that the average diameter of the particles is around 6 nm. X-ray diffraction (XRD) studies further confirmed the formation of the spinel Co3O4. Purity of the products was detected by Fourier transform infrared spectroscopy (FTIR) combined with thermal gravimetric analysis (TG/DTG). The magnetic measurements revealed a small hysteresis loop at room temperature indicating a weak ferromagnetic nature of the synthesized Co3O4 nanoparticles. The magnetic moment of the particles was measured to be 4.27 μeff.  相似文献   
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