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961.
Steven J. Sackett James M. Kelley Peter P. Gillis 《Journal of The Franklin Institute》1977,304(1):47-63
Using our constitutive theory for polycrystalline plasticity, we have calculated characteristic yield conditions for several sample materials in which the dependence of the dislocation velocity on stress is given by an empirical power function. The shape of the yield surfaces for these materials varies resembling that of von Mises when the stress exponent is small and that of Tresca when the exponent is large. Additional examples illustrate the ability of the proposed theory to model such phenomena as the development of anisotropy during plastic deformation, material hardening and softening, the occurrence of upper and lower yield points, and a Bauschinger effect. 相似文献
962.
963.
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
964.
Ajay Kumar T. A. Venkita Subramanian Usha P. Sharma 《Indian journal of clinical biochemistry : IJCB》1992,7(2):165-168
Protein fraction termed P2 was obtained from sonicates of Mycobacterium smegmatis, subjected to ammonium sulphate precipitation. P2 fraction was further fractionated into 4 fractions (PeakI-IV) by DEAE cellulose ion-exchange chromatography. ELISA was performed
on the sera of 104 tuberculous cases and 62 controls, using P2 fractions Peak I as test antigens. Though the mean ELISA values in tuberculous cases were higher than the controls, no statistically
significant difference was found between the two. Antigens P2, Peak I and IV were tested on Western blots with pooled sera from tuberculous cases as well as controls. P2 fraction, Peak-I and IV were separated on PAGE-SDS, electroblotted onto nitrocellulose Sheets and the blots were subjected
to ELISA. Peak IV appeared as a single band (M.W. 55,000). P2 fraction exhibited some discriminatory bands on development of blots. 相似文献
965.
In this paper, an algorithm is developed to apply Hann, Hamming, Blackman and related windows directly in the transform domain for the discrete cosine transform and discrete sine transform. These algorithms are useful in applications where windowing is required in order to minimize edge effects caused by implicit symmetries in the transform domain that are not replicated in the real-world data. Examples of such applications include data communication, adaptive system identification and filtering, real-time analysis of financial market data, etc. Software implementations in C language are also given. 相似文献
966.
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
967.
968.
Ishrat Kareem S. A. Jaweed J. S. Bardapurkar V. P. Patil 《Indian journal of clinical biochemistry : IJCB》2004,19(2):124-127
The present study was undertaken in 100 subjects, 30 diabetics without complication (group I), 40 diabetics with retinopathy
(group II) and 30 non diabetic as normal control group (group III). Blood sugar levels, magnesium, cholesterol and triglyceride
were analyzed from plasma and serum. The results were correlated with degree of diabetic control from the levels of glycosylated
hemoglobin. Serum magnesium levels in group II were found to be significantly lowered than in group I. There was also significant
difference in magnesium levels of group I and group III. We found a significant correlation between the glycosylated hemoglobin
and magnesium levels in our study.
The results also indicate that the patients with diabetic retinopathy showed significant rise in serum cholesterol and triglyceride.
Probably hypomagnesemia and increased serum cholesterol and triglyceride levels are responsible for microvascular changes
in diabetes leading to retinopathy. The purpose of this study was thus to gather information about the degree of control of
diabetes and magnesium status. 相似文献
969.
Bhanu P. Singh Banani Banerjee Puspanita Naik Jordan N. Fink Viswanath P. Kurup 《Indian journal of clinical biochemistry : IJCB》2006,21(2):20-27
The ubiquitous fungus Aspergillus fumigatus causes allergic rhinitis, asthma, sinusitis and allergic bronchopulmonary aspergillosis.
A number of major allergens from A. fumigatus are purified, but their structure-function role in the pathogenesis of disease
is not known. Such information is essential for devising alternative therapy of fungal allergic diseases. In the present study,
N-terminal and C-terminal deletion mutants ofAsp f 3 were constructed and their immunopathological responses studied in a mice model of allergy. Three mutants viz,Asp f 3 (aa 33–168), (aa 1–142), and (aa 23–142) were made by deleting certain amino acids from epitopic regions of full lengthAsp f 3, a major allergen of A. furnigatus. TheAsp f 3 and three mutated proteins were expressed in pET vector. The C-terminal deletion mutantAsp f 3 (aa 1–142) induced elevated IFN-γ but low levels of IL-4 by spleen cells. This mutant also showed significant downregulation
of peripheral blood eosinophils and lung inflammation in immunized mice. The N-terminal deletion mutantAsp f 3 (aa 33–168) also exhibited an immuno-suppressive effect in terms of IgE production and induction of Th2 cytokine. The results
indicate thatrAsp f 3 and its deletion mutants induced distinct immune-inflammatory responses in mice on challenge with these proteins. The non-IgE
binding deletion mutants ofAsp f 3 (aa 1–142 and aa 33–168) could deviate Th2 immune response with a concomitant reduction in airway inflammation and infiltration
of inflammatory cells. 相似文献
970.
Garima Mehta Seema Kothari P. P. Singh 《Indian journal of clinical biochemistry : IJCB》2001,16(1):65-71
From January 1992-January 1998, 1404 patients attended the “Breast Clinic” of R.N.T. Medical College M.B. Hospital, Udaipur.
Out of these, 11% and 81% patients had breast cancer (B.C.) and benign breast cancer (B.B.D.) respectively. The oxidative
load in B.C. was 2.32 times higher than controls, but comparable to B.B.D. β-Carotene deficiency was uncommon in patients,
whereas vitamin A deficiency was almost equally common in both B.C. and controls. Most of the patients had almost depleted
levels of α-tocopherol and ascorbic acid but their TBAR levels were in normal range. The data in the present study when compared
with B.B.D. and other local normal subjects point out: a) oxidative burden in B.C. is a consequence and not the cause of the
disease, (b) oxidative stress could be one of the etiological factors in tumor expression, which need not to be malignant
and c) α-tocopherol and ascorbic acid are not importantly responsible for higher oxidative burden in B.C. 相似文献