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101.
Photovoltaic (PV) water pumping systems have been widely tested and assessed in Indonesia because of the deficiency of potable water in remote areas. Several different PV water pumping systems, such as a.c./d.c. with/without battery and various pumps, have been tested in the field. Further study, evaluation and classification of optimized PV water pumping systems is needed. Three of those pumping systems were installed in Sumba Island in 1983, in three adjacent villages with similar climate and environment conditions. Two of the installations had a.c. direct coupled systems and the other had d.c. The a.c. systems used a 3.65 kWp PV generator each and the d.c. system used 5.76 kWp. After comparing the performance data of both systems, it can be concluded that the a.c. system performs better and needs less maintenance on the pump. In May 1987, as a result of this evaluation, the 5.76 kWp d.c. system was replaced by an a.c. one, and its capacity was increased to 9.22 kWp. Meanwhile, the 3.65 kWp a.c. system was increased to 3.88 kWp.  相似文献   
102.
OBJECTIVE: To compare the association of income and education with breast and cervical cancer screening in Ontario, Canada, and the United States. DESIGN: Survey using data from the Ontario Health Survey and the US National Health Interview Survey. PARTICIPANTS: A multistage random sample of women aged 18 years and older living in households in Ontario (N = 23,521) and the United States (N = 23,932) in 1990. MAIN OUTCOME MEASURE: Persons were considered screened if they reported a Papanicolaou test within the previous 2 years, a clinical breast examination within the previous year, or a mammogram within the previous year. RESULTS: Papanicolaou test and clinical breast examination rates were similar between countries, but mammography rates were two to three times higher in the United States across all age groups. Compared with women with less than a high school degree, college graduates were more likely to receive screening (odds ratio [OR], 1.5; 95% confidence interval [CI], 1.2 to 1.7) and there was no difference between countries. Across all procedures, women with higher incomes were more likely to receive screening. For Papanicolaou test and clinical breast examination, there was no difference between countries. Compared with the lowest income, the OR was 1.7 (95% CI, 1.3 to 2.1) in Ontario and 1.9 (95% CI, 1.6 to 2.2) in the United States for Papanicolaou test and 2.1 (95% CI, 1.6 to 2.8) in Ontario and 2.1 (95% CI, 1.8 to 2.6) in the United States for the clinical breast examination for women with income greater than $45,600 (US dollars). For mammography screening, the association of income with use was greater in the United States: the OR was 1.8 (95% CI, 1.3 to 2.6) in Ontario and 2.7 (95% CI, 2.3 to 3.2) in the United States for women with income greater than $45,600 (US dollars). CONCLUSIONS: Despite the long-time presence of universal insurance coverage in Ontario the disparities in the use of cancer screening procedures by the poor were similar to the United States. Universal coverage is not sufficient to overcome the large disparities in screenings across socioeconomic status demonstrated in both countries.  相似文献   
103.
p-Cymene-2,3-diol, carvacrol and thymol are components of thyme that exhibit antioxidant activities. The concentration of each substance was determined in different foodstuffs containing thyme extract. The stabilities ofp-cymene-2,3-diol, carvacrol and thymol were examined by heating lard containing thyme extract at temperatures from 80 °C to 160 °C.  相似文献   
104.
Effects of the Leslie viscosity coefficients αi (i = 1, 2, …, 5) of nematic liquid crystals (NLCs) with negative dielectric anisotropy (Δε < 0) on the electric-field-induced director reorientation in homeotropic NLC cells have been studied from the analysis of the transient current induced by step voltage application. The transient current in a homeotropic NLC cell with Δε < 0 was well reproduced by computer simulation, based on the theory of NLCs in which the flow effects and the free-slip boundary condition are taken into account. It is found that the response time of vertical alignment NLC displays is dominantly governed by α2 and α4 + α5 of NLCs with Δε < 0.  相似文献   
105.
A biochemical study was performed in two patients submitted to insulin coma therapy. The injection of insulin resulted in a decrease of free and total tryptophan as well as tyrosine in plasma, while NEFA were not influenced by this treatment. The ratio of tryptophan to tyrosine was enhanced. The administration of glucose after insulin provoked an increase of free and total tryptophan. The results support the hypothesis that in man insulin may favor the uptake of tryptophan by the brain, and enhance the synthesis of cerebral serotonin.  相似文献   
106.
107.
Conducted 4 experiments with a total of 188 rat pups to test the hypothesis that rat pups can learn persistence at age 11 days but cannot express this learning in their behavior until they are a few days older. Exp I used a space-trial procedure to investigate the relative reinforcing effects of milk suckling, dry suckling, and contact without suckling at ages 11 and 14 days. Exp II used the Exp I procedure, manipulating schedule of reward at 2 ages and under 2 of the reward conditions. Exp III manipulated the dry suckling reward schedule in 11- and 14-day-old pups. Exp IV manipulated partial and continuous reinforcement on Day 11 but tested for persistence on Day 14. Results suggest the existence of a traditional period in neonatal rats for the learning of persistence. Partial reinforcement training with suckling on an anesthetized dam as reward induced greater persistence in extinction of the approach response than did continuous reinforcement in rat pups 14 days old but not in 11-day-old pups. Other aspects of this period of development are discussed. (26 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
108.
109.
Presents a case study of a 37-yr-old female patient with an expressive aphasia secondary to a traumatic brain injury. The development of successive approximations of a speech prosthesis for the S illustrated how new hardware and software capabilities permit the rapid iterative design and redesign of cognitive prosthesis tools. However, the rehabilitation infrastructure supporting microcomputer implementation needs to be developed. The emergence of ProsthesisWare, a class of rehabilitation software, constitutes an application of microcomputers that offers utilitarian prosthetic aids for activities of daily living for some people with cognitive impairments. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
110.
PURPOSE: To quantify regional cerebral blood volume (rCBV) on the basis of the enhancement of blood proton relaxation rates after intravenous administration of gadopentetate dimeglumine. METHODS: A series of sequential MR images on one section was recorded during bolus transit with a standard fast low-angle shot sequence. The signal-intensity curves were converted into corresponding concentration-time curves from which rCBV images were calculated. RESULTS: The functional parameter images of rCBV were calculated pixel-by-pixel for two patients who had received a 1-second bolus injection of 1 mmol of gadopentetate dimeglumine. In a larger series of 62 patients, a mean blood volume of 4.6 +/- 1.6 vol% was determined for normal brain tissue. CONCLUSIONS: The relaxing effect of a contrast agent can be used to determine blood volume quantitatively. The results are in agreement with those obtained by nuclear medicine techniques. The proposed method requires no special hardware, and can thus be implemented on clinical MR scanners.  相似文献   
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