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941.
Study on arsenic level in public water supply of Delhi using hydride generator accessory coupled with atomic absorption spectrophotometer 总被引:1,自引:0,他引:1
Sanjeev Lalwani T. D. Dogra D. N. Bhardwaj R. K. Sharma O. P. Murty 《Indian journal of clinical biochemistry : IJCB》2006,21(1):70-76
Exposure to arsenic has been associated with several health hazards. Worldwide the main reason for chronic human intoxication
with arsenic is intake of contaminated drinking water. Air acetylene type of atomic absorption spectrophotometer in combination
with hydride generator accessory was used to analyze arsenic level in 25 water samples collected from 25 booster pumping stations
and 313 water samples collected from tap water supply of 62 areas of Delhi. Results were analyzed using SPSS and Barlett’s
Chi Square Test. Mean arsenic level detected in water samples collected from booster pumping stations was 0.00976 ppm (Range
0.000–0.017 ppm, Standard Deviation 0.006 and Standard error of Mean 0.00118). Maximum arsenic level (0.017 ppm) was found
in water samples of booster pumping stations of Mehrauli, Punjabi Bagh and Ramjas Road. Mean arsenic level detected in samples
collected from tap water supply was 0.013 ppm (Range 0–0.0430 ppm, Standard Deviation 0.00911 and Standard error of Mean 0.000515).
In water samples of 42 areas arsenic level detected was exceeding WHO/EPA permissible limit of 0.01 ppm (10 ppb). The mean
arsenic level detected in water samples of booster pumping station was within WHO/EPA permissible limit while mean arsenic
level detected in tap water samples was marginally higher. Mixing of ground water and contamination through broken or leaking
channel could be the possible reason of higher arsenic level in tap water. Continuous monitoring of quality of drinking water
is required particularly in view of water contamination caused by industrial waste and uncontrolled ground water extraction. 相似文献
942.
This paper is an attempt to present disclosive ethics as a framework for computer and information ethics – in line with the
suggestions by Brey, but also in quite a different manner. The potential of such an approach is demonstrated through a disclosive
analysis of facial recognition systems. The paper argues that the politics of information technology is a particularly powerful
politics since information technology is an opaque technology – i.e. relatively closed to scrutiny. It presents the design
of technology as a process of closure in which design and use decisions become black-boxed and progressively enclosed in increasingly
complex socio-technical networks. It further argues for a disclosive ethics that aims to disclose the nondisclosure of politics
by claiming a place for ethics in every actual operation of power – as manifested in actual design and use decisions and practices.
It also proposes that disclosive ethics would aim to trace and disclose the intentional and emerging enclosure of politics
from the very minute technical detail through to social practices and complex social-technical networks. The paper then proceeds
to do a disclosive analysis of facial recognition systems. This analysis discloses that seemingly trivial biases in recognition
rates of FRSs can emerge as very significant political acts when these systems become used in practice.
Paper prepared for the Technology and Ethics Workshop at Twente 相似文献
943.
Praveen Sharma P. K. Sharma D.Sc. J. Pramod L. K. Kothari Rashmi Ranka Sushma Sharma 《Indian journal of clinical biochemistry : IJCB》1989,4(1):62-64
Sixteen weeks of chronic vitamin C deficiency, induced in guinea pigs by restricted vitamin C intake, resulted in a marked
increase in the serum total LDL- and VLDL- cholesterol, triglycerides and total lipids. HDL-cholesterol decreased resulting
in a highly significant increase in LDL/HDL ratio. The results reconfirm that vitamin C deficiency causes changes in blood
lipid profile which could promote atherogenesis. 相似文献
944.
M. Maneesh Sanjiba Dutta Amit Chakrabarti D M Vasudevan 《Indian journal of clinical biochemistry : IJCB》2007,22(1):138-142
Infertility is well-established harmful effect in chronic alcoholism and so far, there is no effective treatment for this
condition. The study was conducted to determine the effects of alpha tocopherol on ethanol induced testicular injuries in
male albino rats of Wistar strain. Five groups (n=6) of animals were used. Group I served as control. Group II received daily
1.6g ethanol/kg body weight/day for 4 weeks orally. Group III received 1.6g ethanol+80mg alpha tocopherol/kg body weight/day
for four weeks orally. Group IV received 1.6g ethanol/kg body weight for/day 4 weeks and followed by 80mg alpha tocopherol/kg
body weight/day for four weeks orally. Group V received 1.6g ethanol/kg body weight/day orally for 4 weeks, followed by 4
weeks abstinence. Twently-four hours after the last treatment the rats were sacrificed using anesthetic ether. Testes were
removed and used for the estimation of extent of lipid peroxidation and tissue levels of antioxidants and steroidogenic enzymes.
Alpha tocopherol treatment increased the activities of testicularΔ
5, 3β-HSD. Moreover, the treatment was also associated with significant decrease in testicular oxidative stress. Ethanol-induced
oxidative stress and decreased steroidogenesis can be reversed by treatment with alpha tocopherol. 相似文献
945.
Bruce D.Henderson 《科技创业月刊》2002,(4):33
任何一个复杂的问题都是近乎无数的事实和关系的组合。商业行为尤其受到方方面面的影响,包括过去的、非逻辑的和不可知的事物的影响。这种复杂性又因目标不同与服务于各种各样的顾客的需要而更加盘根错节,而顾客的许多目标不得不经过权衡后放弃。在这样复杂的条件下解决问题需要井井有条的、系统的方法以试图优化最后的决定。 相似文献
946.
947.
It is shown that a p+q node graph Gc representation can be drawn for a chessboard C(p,q) i.e. an array of p rows and q columns. It is shown further that the coefficients of the rook polynomial for C(p,q) correspond 1:1 inversely with the coefficients of the chromatic polynomial for Gc written in factorial form. 相似文献
948.
R. Kumar S. B. Pachori G. K. Senger Satyanand L. D. Joshi 《Indian journal of clinical biochemistry : IJCB》1994,9(2):72-74
Aim of present study was to compare the adenosine deaminase (ADA) activity in various types of arthritis conditions with synovial
effusion. No. significant difference was observed in ADA activity in serum of control and study groups but results have shown
a definite pattern of ADA activity in synovial fluid in various arthritic conditions. The highest value of ADA activity was
observed in synovial fluid of patients with tubercular arthritis followed by rheumatoid, septic, osteo and post traumatic
arthritis. Thus measurement of ADA activity in synovial fluid can be used as a parameter of differential diagnosis of arthritis
specially tubercular in initial stages. 相似文献
949.
For some 300 years the modelling of uncertainty in the sciences has been totally dominated by probabilistic methods. Now, following major criticism of the theoretical foundations of probability theory, other approaches to dealing with uncertainty are being explored. 相似文献
950.