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1.
Radon gas, which is the main contributor to human radiation exposure, is easily dissolved in, and dissipated from, water. Problems with radon occur because, in addition to being ingested, it (a) becomes attached to particles which lodge in the lungs and (b) emits alpha radiation. Concentration has been found to increase inversely with the size of a water supply. Although of little problem in mains'water, private water supplies in the UK have been found to contain more than ten times the recommended US levels. Despite this, very little monitoring is carried out for radon in private supplies. Local authorities, situated in areas where the geological conditions are such that high levels of radon would be expected, should carry out a suitable sampling and monitoring programme of their private water supplies.  相似文献   
2.
Although rapid smoking has proved to be a successful treatment strategy for smokers, its hazard potential has been recently debated. In the present study, 6 Ss (mean age 30.8 yrs) were monitored throughout 8 standard sessions of rapid smoking. Heart rate, blood pressure, and carboxyhemoglobin increases were generally higher than those reported in the few extant physiological studies of rapid smoking, and EKG abnormalities occurred in several Ss during rapid smoking. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
3.
Design of a space channel simulator using virtual instrumentation software   总被引:2,自引:0,他引:2  
The ability to simulate satellite channels gives protocol designers the ability to test design options prior to their use in space communications. Here, we describe a software-based space channel simulator with variable channel error-rate, channel delay, and user bit error rate. This simulator is used to model the communications channel for testing various Internet-type protocol options for space communications.  相似文献   
4.
The iron-chelating agent desferrioxamine now finds extensive use in the treatment and diagnosis of aluminum-related diseases in renal patients. We review the chemistry and pharmacokinetics of desferrioxamine in chelation therapy for patients on hemodialysis.  相似文献   
5.
The objective of this study was to estimate genetic parameters for grass dry matter intake (DMI), energy balance (EB), and cow internal digestibility (IDG) in grazing Holstein-Friesian dairy cows. Grass DMI was estimated up to 4 times per lactation on 1,588 lactations from 755 cows on 2 research farms in southern Ireland. Simultaneously measured milk production and BW records were used to calculate EB. Cow IDG, measured as the ratio of feed and fecal concentrations of the natural odd carbon-chain n-alkane pentatriacontane, was available on 583 lactations from 238 cows. Random regression and multitrait animal models were used to estimate residual, additive genetic and permanent environmental (co)variances across lactations. Results were similar for both models. Heritability for DMI, EB, and IDG across lactation varied from 0.10 [8 days in milk (DIM)] to 0.30 (169 DIM), from 0.06 (29 DIM) to 0.29 (305 DIM), and from 0.08 (50 DIM) to 0.45 (305 DIM), respectively, when estimated using the random regression model. Genetic correlations within each trait tended to decrease as the interval between periods compared increased for DMI and EB, whereas the correlations with IDG in early lactation were weakest when measured midlactation. The lowest correlation between any 2 periods was 0.10, −0.36, and −0.04 for DMI, EB, and IDG, respectively, suggesting the effect of different genes at different stages of lactations. Eigenvalues and associated eigenfunctions of the additive genetic covariance matrix revealed considerable genetic variation among animals in the shape of the lactation profiles for DMI, EB, and IDG. Genetic parameters presented are the first estimates from dairy cows fed predominantly grazed grass and imply that genetic improvement in DMI, EB, and IDG in Holstein-Friesian cows fed predominantly grazed grass is possible.  相似文献   
6.
Despite the association of increasing age with chronic wound-healing disorders and an impaired rate of healing of acute cutaneous wounds, the role of matrix metalloproteinases (MMPs) is unknown. To determine the spatial and temporal patterns and activities of MMP-1, -2, -3 and -9, 132 healthy humans aged between 19 and 96 years underwent 4-mm punch biopsies followed by wound excision between day 1 and day 180 post-wounding. Wounds showed an age-related increase in MMP-2 and MMP-9 immunostaining from day 3; this was associated with degradation of gelatin as shown by zymograms and with increased proteinase activity as shown by azocoll assays. Distinct spatial localisations for each MMP were observed: MMP-2 was found in epidermal structures; MMP-9 was observed in inflammatory cells up to day 21; MMP-1 was localised to keratinocytes at the wound margin. Normal old skin showed pro-MMP-2 bands on zymography and increased MMP-2 immunostaining. These results indicate that: (1) intrinsic ageing is associated with the up-regulation of MMPs previously associated with chronic wound healing; (2) wound-tissue proteinases are essentially active up to day 21 postwounding; and (3) intrinsic ageing may predispose to tissue breakdown disorders because of MMP-2 up-regulation in normal skin.  相似文献   
7.
Cognitive, behavioral, and combined assertiveness treatments for dysfunctional job-interviewing skills were evaluated in a design that included high-demand and waiting list control treatments as well. Cognitive, behavioral, generalization, and control measures were used to determine the construct validity of hypothesized improvements. The cognitive treatment had no impact on any outcome variable. Some evidence to favor the behavioral treatment appeared on the cognitive assessment battery. However, given the failure of the behavioral treatment to register parallel changes on the behavioral battery, these cognitive improvements are not clearly attributable to behavioral theory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
8.
Energy production from a coblended mixture of biosolids and food waste was optimised for hydrogen and methane production. Four different blends were prepared by varying the carbohydrate : protein (carb : pro) ratios. The biosolids contained a low carbohydrate fraction and so was not suitable for hydrogen production when used alone. However coblending this waste with a carbohydrate‐enriched food waste produced a greater hydrogen yield, making this option viable. Batch studies showed that the optimised mix had a biosolids concentration of 25.7% (w/w). The largest hydrogen yield of 198.5 mL/gVSremoved was observed when the carb : pro was 2.78, and this was threefold higher than the other carb : pro ratios evaluated in this study. The digestate recovered after hydrogen recovery had a C : N of 17.5, which is in the ideal range for methane production. The biochemical methane potential test showed a methane yield of 239 mL/gVSremoved, and the total volatile solids destruction following two‐phase hydrogen and methane production was 93%.  相似文献   
9.
A social marketing approach used both qualitative and quantitative methods to develop a hygiene behaviour intervention in rural north-east Thailand. Behaviours were preselected from a previous study and the intervention was designed to promote hand washing, especially before feeding a baby, cooking, eating, and after defaecation or cleaning a baby's bottom, and dish washing immediately after eating. A bacteriological indicator (enumerating faecal streptococci using a finger impression technique) was developed to measure changes in hand washing behaviour and observation (spot checks) of dirty dishes to indicate dish washing practice. There was a significant improvement in both behaviours and a significant reduction in diarrhoeal disease as a result of the intervention. Furthermore, both indicators were retrospectively found to be positively related to diarrhoeal disease incidence. However, receiving and being able to recall the intervention messages was not necessarily sufficient to ensure behaviour change, as some adults found it difficult to change old habits. Villages showing the greatest improvement tended to have a stronger sense of community than others and to have more people actively involved in the intervention.  相似文献   
10.
60 male and female 24–50 yr old recovering alcoholic counseling clients were assigned randomly to 1 of 3 male counselors and to 1 of 2 treatment conditions. In the nonstandard English condition, the counselor casually and passively introduced 4 profane words. The standard English condition was identical except in respect to the use of these specific words. On client self-report and behavioral measures, which cut across all schools of counseling, counselors who used nonstandard English were judged to be less effective and satisfying. (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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