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91.
V.K. Raina K. Sasidharan Samiran Sengupta Tej Singh 《Nuclear Engineering and Design》2006,236(7-8):770-783
At present Dhruva and Cirus reactors provide the majority of research reactor based facilities to cater to the various needs of a vast pool of researchers in the field of material sciences, physics, chemistry, bio sciences, research & development work for nuclear power plants and production of radio isotopes. With a view to further consolidate and expand the scope of research and development in nuclear and allied sciences, a new 20 MWt multi purpose research reactor is being designed. This paper describes some of the design features and safety aspects of this reactor. 相似文献
92.
The costs of remedial work, and the radon level reduction achieved, have been studied in a series of domestic properties in Northamptonshire, which is a radon affected area. The cost-effectiveness of the series is similar to published theoretical estimates for proposed national remediation programmes, and five times more effective than our similar analysis for the National Health Service workplace, if it is assumed that 100% of householders discovering levels above 300 Bq m-3 implement remediation. In practice, in the UK, far fewer of those who arrange an initial radon test proceed to remediation, but this domestic programme could be cost effective if more than 5% carry out remediation. Our series confirms that a considerable number of householders with radon levels in the 200 to 300 Bq m-3 range do not seek or implement remediation work. 相似文献
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26 clinician trainees' recollections of experiences in a diagnostic preschool program were analyzed in terms of strength and weaknesses of the program. 相似文献
97.
Abstracts are not published in this journal
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
98.
Spina bifida, a congenital deformity of the posterior wall of vertebrae of the spine, is a midline defect of skin, vertebral arches and neural tube, usually in the lumbosacral region. Its incidence is reported to be 0.2 to 0.4 per 1000 live births. Various hypotheses have been put forward as etiological factors for spina bifida including consumption of potato affected by blight and hardness of drinking water but these have not been proven. Two groups of 50 randomly chosen children were established. The study group consisted of children aged 5 to 12 years, weighing 15 to 30 kg, consuming fluoride rich drinking water (4.5 and 8.5 ppm fluoride; WHO permissible limit is 1.5 ppm fluoride), and manifesting either clinical, dental and/or skeletal fluorosis. The control group consisted of age and weight-matched children, consuming less than or equal to 1.5 ppm fluoride in drinking water and not showing any evidence of fluoride toxicity. These children were evaluated for antenatal history, general clinical examination (especially for dimples, tufts of hair, haemangioma on skin throughout the length of spine), other congenital abnormalities, evidence of fluoride toxicity, biochemical estimation for fluoride levels in blood and serum and by skiagrams of the spine to examine for the presence of spina bifida occulta. A total of 22 (44%) of the 50 children in group A, the study group, and 6 (12%) of the 50 children in group B, the control group, revealed spina bifida occulta in the lumbosacral region.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
99.
The gene rafY from the plasmid pRSD2, which enables Escherichia coli to grow on raffinose, was transferred into expression plasmid pUSL77. The protein was expressed in the porin-deficient Escherichia coli strain KS26 and was isolated and purified to homogeneity. The pure protein was reconstituted into lipid bilayer membranes. It formed an ion-permeable channel with a single-channel conductance of 2.9 nS of the open state in 1 M KCl, which is approximately twice of that of the general diffusion pores OmpF and OmpC of E. coli outer membrane. At lower pH the channel exhibited rapid flickering between three substates of the open channel. The RafY channel appears to be wide and water filled and has a small selectivity for cations over anions. Although RafY is part of an uptake and fermentation system for raffinose it does not contain a binding site for carbohydrates. Our results suggest that RafY is a general diffusion pore with a diameter, larger than that of the general diffusion porins OmpF and OmpC, that allows the diffusion of high-molecular-mass carbohydrates through the outer membrane. 相似文献
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