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131.
Electrical power supply has grown enormously during this century. In 1950 the total capacity of generators producing electricity in India was less than 3000 MW. Today, the power generating capacity is around 120,000 MW. The polyphase AC system, which is to a large extent the legacy of Nikola Tesla, is central to all power generation. Power systems these days are complex interconnected networks spread across the country. How are they structured? How have we been doing in India?  相似文献   
132.

Forty-five Israeli gay men unfolded their life stories in order to delve into their media reception patterns. Overall, they prefer to disengage themselves from a discourse that symbolically annihilates them or negatively constructs their representations. Absence from the mediated reality as well as social invisibility are perceived to reduce ontologically the gay individual. On the other hand, these narrators exhibited intentional consumption of texts that refer to gay issues and figures. The gay individual who regularly senses that his self is being negated attributes great value to images that can validate his existence, and hence allocates resources in their consumption. Both patterns of reception complement each other and shed light on the complex dialectics between marginally situated, muted co-culture members and the public sphere.  相似文献   
133.
Currently employed markers for the detection of acute coronary syndrome are Troponin T, CK (Creatine Kinase) and CKMB activity. CKMB activity measured by immunoinhibition method can give falsely elevated results due to the presence of atypical CK and CKBB and at times lead to the mis-diagnosis of acute coronary syndrome. Hence, CKMB mass (CKMB) measured by electrochemiluminence sandwich principle was employed. In this cross-sectional study 183 samples of 61 patients were analyzed within 6 h of diagnosis of acute coronary syndrome and followed up to 72 h. The correlation coefficient between CKMB activity and CKMBM at 4–6 h was 0.744, while at 12–24 h it was 0.909 and at 48–72 h it was 0.337. Thus there was good association between the two methods at 12–24 h but, statistically for method comparison studies and for replacing one method by another, the two methods need to be in agreement with one another. In this study the two methods are not in agreement with one another and thus analytically not replaceable. Another finding was obtained that CKMBM reached cut off levels prior to CKMB enzyme activity and hence, CKMBM is clinically better than CKMB activity to detect reinfarction.  相似文献   
134.
A 50 year old male was admitted in our hospital with anemia and impaired renal function. He was subsequently found to have extremely elevated serum phosphate level (24 mg/dL, reference interval: 2.5–4.5 mg/dL) with normal serum calcium when assayed on a Beckman Coulter AU 480® analyser. Clinico-biochemical discrepancy led to the suspicion of spurious hyperphosphatemia. Serum total protein was grossly elevated with gross reversal of albumin to globulin ratio. Serum electrophoresis revealed a large M band and was confirmed as Ig G-Kappa type on immunofixation. Subsequently a bone marrow aspiration biopsy confirmed the diagnosis of multiple myeloma. The patient serum was then reassayed for phosphate on a Vitros® 250 Dry Chemistry platform and the result was within normal reference interval. Paraproteinemias are a common cause of analytical interference in clinical biochemistry laboratories and as multilayered film technology platforms like Vitros® assay most routine analytes on a protein free filtrate they are unaffected by paraprotein interference. Clinically discordant patient results should always be interpreted keeping such interferences in mind.  相似文献   
135.
Investigation of single molecule DNA dynamics in confined environments has led to important applications in DNA analysis, separation, and sequencing. Here, we studied the electrophoretic transport of DNA molecules through nanochannels shorter than the DNA contour length and calculated the associated translocation time curves. We found that the longer T4 DNA molecules required a longer time to traverse a fixed length nanochannel than shorter λ DNA molecules and that the translocation time decreased with increasing electric field which agreed with theoretical predictions. We applied this knowledge to design an asymmetric electric pulse and demonstrate the different responses of λ and T4 DNA to the pulses. We used Brownian dynamics simulations to corroborate our experimental results on DNA translocation behaviour. This work contributes to the fundamental understanding of polymer transport through nanochannels and may help in designing better separation techniques in the future.  相似文献   
136.
137.
During the last few decades research activities have grown rapidly in Ethiopia. Introduction of higher education and foreign assistance for this purpose have led the Ethiopian Government to set up several research institutes in the country. The Institute of Ethiopian Studies is one of them, set up to enable research activities in various areas of Ethiopian culture as well as to provide a documentation centre for them. Information and documentation are considered to be the infrastructure of research work. The present state of information and documentation services of the Institute is briefly described along with its history, activities and sections. The importance of introducing some new devices, such as compiling bibliographies, cumulative indexes, book lists and starting a newsletter to keep the researchers abreast of new developments at the Institute.  相似文献   
138.
Preterm delivery is a major contributor for neonatal mortality. Intensive research is underway to establish a reliable biomarker that can ascertain the risk of preterm delivery in pregnant women. The aim of our study was to evaluate the role of various biochemical parameters as potential biomarker for risk assessment for preterm labor. Forty women presenting with preterm labor and 40 women who delivered at term were included in the study. Parameters that were evaluated include corticotrophin (ACTH), prolactin, thyroid stimulating hormone (TSH), ferritin and Alkaline Phosphatase (ALP). Serum ACTH, ferritin, ALP and Ferritin/Iron ratio were significantly higher in the subjects who delivered prematurely as compared to the controls. Comparison of sensitivity, specificity, likelihood ratio, positive and negative predictive values for different cut offs for ACTH, ferritin, ALP and ferritin/iron ratio was carried out. Ferritin emerged as the best marker with area under curve of 0.96 as compared to 0.88 for ACTH, 0.825 for ALP and 0.735 for ferritin/iron ratio. Our study establishes the superiority of ferritin as a predictive biomarker for preterm labor as compared to the rest of the parameters evaluated.  相似文献   
139.
To correlate blood lead levels (BLLs) and oxidative stress parameters in pregnant anemic women. A total of 175 pregnant women were found suitable and included for this study. Following WHO criteria, 50 each were identified as non-anemic, mild anemic and moderate anemic and 25 were severe anemic. The age of all study subjects ranged from 24–41 years. At admission, BLLs and oxidative stress parameters were estimated as per standard protocols and subjected with ANOVA, Pearson correlation analysis and cluster analysis. Results showed significantly (p < 0.01) high BLLs, zinc protoporphyrin (ZPP), oxidized glutathione (GSSG), lipid peroxide (LPO) levels while low delta aminolevulinic acid dehydratase (δ-ALAD), iron (Fe), selenium (Se), zinc (Zn), haemoglobin (Hb), haematocrit (Hct), mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH), mean corpuscular haemoglobin concentration (MCHC), red blood cell (RBC) count, reduced glutathione (GSH), superoxide dismutase (SOD), catalase (CAT) and total antioxidant capacity (TAC) in all groups of anemic pregnant women as compared with non anemic pregnant women. In all groups of pregnant women, BLLs showed significant (p < 0.01) and direct association with ZPP, GSSG and LPO while inverse relation with δ-ALAD, Fe, Se, Zn, Hb, Hct, MCV, MCH, MCHC, RBC, GSH, SOD, CAT and TAC. Study concluded that low BLLs perturb oxidant-antioxidant balance and negatively affected hematological parameters which may eventually Pb to Fe deficiency anemia during pregnancy.  相似文献   
140.
Hemoglobin J-Rajappen (alpha)90 Lys → Thr is an alpha chain variant found in heterozygous state and presents normal hematological blood picture. Due to the ambiguity in results obtained while analyzing by HPLC and alkaline gel electrophoresis, we report this rare case of HbJ-Rajappen using non denaturing gel electrophoresis and matrix assisted laser desorption ionization mass spectrometry. Though HbJ-Rajappen has earlier been reported using different techniques, this is the first report being validated using mass spectrometry technique.  相似文献   
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