The legacy of Nikola Tesla     

D P Sen Gupta 《Resonance》2007,12(4):69-79

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   

SCADA data based condition monitoring of wind turbines     

Ke-Sheng Wang  ;Vishal S.Sharma  ;Zhen-You Zhang 《上海大学学报(英文版)》2014,(1):61-69

Wind turbines（WTs） are quite expensive pieces of equipment in power industry. Maintenance and repair is a critical activity which also consumes lots of time and effort, hence making it a costly affair. Carefully planning the maintenance based upon condition of the equipment would make the process reasonable. Mostly the WTs are equipped with some kind of condition monitoring device/system, which provides the information about the device to the central data base i.e., supervisory control and data acquisition（SCADA） data base. These devices/systems make use of data processing techniques/methods in order to detect and predict faults. The information provided by condition monitoring equipments keeps on recoding in the SCADA data base. This paper dwells upon the techniques/methods/algorithms developed, to carry out diagnosis and prognosis of the faults, based upon SCADA data.Subsequently data driven approaching for SCADA data interpretation has been reviewed and an artificial intelligence（AI） based framework for fault diagnosis and prognosis of WTs using SCADA data is proposed.  相似文献   

Spurious Hyperphosphatemia in a Case of Multiple Myeloma     

Sutirtha Chakraborty  Susruta Sen  Debkishore Gupta  Sidhartha Sankar Ghosh  Prasad Sawant  Mandrita Das 《Indian journal of clinical biochemistry : IJCB》2014,29(2):250-252

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   

DNA translocation through short nanofluidic channels under asymmetric pulsed electric field     

C. Gupta  W.-C. Liao  D. Gallego-Perez  C. E. Castro  L. J. Lee 《Biomicrofluidics》2014,8(2)

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   

On Static and Dynamic Intuitive Ontologies     

David Hammer  Ayush Gupta  Edward F. Redish 《学习科学杂志》2013,22(1):163-168

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The institute of Ethiopian studies library and its documentation services     

Sushma Gupta 《International Information and Library Review》2013,45(4):381-389

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   

Potential Biochemical Markers for Preterm Labor: A Pilot Study in North India     

Singh B  Goswami B  Gupta N  Bajaj AD  Mallika V 《Indian journal of clinical biochemistry : IJCB》2011,26(1):41-45

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   

Extracellular Methemoglobin Mediated Early ROS Spike Triggers Osmotic Fragility and RBC Destruction: An Insight into the Enhanced Hemolysis During Malaria     

S. N. Balaji  Vishal Trivedi 《Indian journal of clinical biochemistry : IJCB》2012,27(2):178-185

Malaria infection is known to cause severe hemolysis due to production of abnormal RBCs and enhanced RBC destruction through apoptosis. Infected RBC lysis exposes uninfected RBC to the large amount of pro-oxidant molecules such as methemoglobin. Methemoglobin (MetHb) exposure dose dependently makes RBCs susceptible to osmotic stress and causes hemolysis. MetHb mediated oxidative stress in RBC correlated well with osmotic fragility and hemolysis. Interestingly, a reactive oxygen species (ROS) spike at 15 min was responsible for the observed effects on RBC cells. Two natural antioxidants N-acetyl cysteine and mannitol protected the RBC from MetHb-mediated defects, which clearly indicated involvement of oxidative stress in the process. MetHb due to its pseudo-peroxidase activity produces ROS in the external microenvironment. Therefore, classical peroxidase inhibitors were tested to probe peroxidase activity mediated ROS production with defects in RBCs. Clotrimazole (CLT), which irreversibly inactivates the MetHb (CLT-MetHb) and abolishes peroxidase activity, did not produce significant ROS outside RBC and was inefficient to cause osmotic fragility and hemolysis. Hence, initiating a chain reaction, MetHb released from ruptured RBC produces significant ROS in the external microenvironment to make RBC membrane leaky and enhanced hemolysis. Together data presented in the current work explored the role of MetHb in accelerated humorless during malaria which could be responsible for severe outcomes of pathological disorders.  相似文献   

Regeneration of Red Cell Cholinesterase Activity Following Pralidoxime (2-PAM) Infusion in First 24 h in Organophosphate Poisoned Patients     

Parul Goel  Nidhi Gupta  Surjit Singh  Ashish Bhalla  Navneet Sharma  K. D. Gill 《Indian journal of clinical biochemistry : IJCB》2012,27(1):34-39

Oximes such as pralidoxime chloride reactivate acetylcholinesterase. However their role in management of organophosphate poisoning is controversial. The study was carried out to find effectiveness of pralidoxime chloride (2-PAM) in regenerating red cell acetyl cholinesterase in first 24 h following administration of it in dose recommended by WHO. Eight patients with OPP [chlorpyriphos (3), phorate (3), dichlorvos (1) and monocrotophos (1) who fulfilled the criteria for inclusion were investigated. In addition to decontamination and atropine, all these patients were administered 30 mg/kg body wt of 2-PAM as bolus dose followed by 7.5 mg/kg body wt/h with maximum dose being 500 mg/h as continuous infusion till first 24 h. Red cell AChE activity was estimated every 15 min for first 4 h, one hourly for next 4 h and then 2 hourly till 24 h and subsequently without 2-PAM every 12 h till 7 days or discharge or death which ever earlier. In all the patients maximum increase in activity was observed in first 4 h following which rise was very slow despite continued 2-PAM infusion and reaching a steady state in 20 h in all the cases. The increase in red cell AChE activity observed in diethyl group at 24 h of 2-PAM infusion was 154% vs. 81% in dimethyl group. At 7 days the increase in activity was 215% vs. 118% respectively. However on multiple repeated ANOVA, no statistically significant difference was observed between diethyl and dimethyl groups at admission and discharge (P > 0.05). Similarly no significant difference was observed in three groups when patients were categorized according to WHO classification of organophosphates (P > 0.05). The maximum increase in red cell AChE activity occurs in first 4 h of 2-PAM administration followed by a slow increase despite 2-PAM infusion till 24 h.  相似文献   

Does LDL-C Estimation Using Anandaraja’s Formula Give a Better Agreement with Direct LDL-C Estimation than the Friedewald’s Formula?     

Shalini Gupta  Minni Verma  Kamaljit Singh 《Indian journal of clinical biochemistry : IJCB》2012,27(2):127-133

Estimation of low density lipoprotein cholesterol (LDL-C) is crucial in management of coronary artery disease patients. Though a number of homogenous assays are available for estimation of LDL-C, use of calculated LDL-C by Friedewald’s formula (FF) is common in Indian laboratories for logistic reasons. Recently Anandaraja and colleagues have derived a new formula for calculating LDL-C. This formula needs to be evaluated before it is extensively applied in diagnosis. We measured LDL-C by homogenous method (D-LDL-C) in 515 fasting samples. Friedewald’s and Anandaraja’s formulas were used for calculation of LDL-C (F-LDL-C and A-LDL-C, respectively). The mean LDL-C levels were 123.3 ± 53.2, 112.4 ± 50.2 and 109.2 ± 49.8 mg/dl for D-LDL-C, F-LDL-C and A-LDL-C, respectively. There was a statistically significant difference between the results (P > 0.001) obtained by calculation formulas compared to the measured LDL-C. There was underestimation of LDL-C by 10.8 and 14 mg/dl by Friedewald’s and Anandaraja’s formulas respectively. The Pearson’s correlation between F-LDL-C and D-LDL-C was 0.931 and that between A-LDL-C and D-LDL-C was 0.930. Bland–Altman graphs showed a definite agreement between mean and differences of the calculation formulas and direct LDL-C with 95% of values lying with in ±2 SD limits. The mean percentage difference (calculated as {(Calculated LDL-C)-(D-LDL-C)}/D-LDL-C × 100) for F-LDL-C was maximum (−11.6%) at HDL-C ≥ 60 mg/dl and TG levels of 200–300 mg/dl (−10.4%) compared to D-LDL-C. A-LDL-C results gave highest mean percentage difference at total cholesterol concentrations <100 mg/dl (−37.3%) and HDL-C < 40 mg/dl (−17.1%), respectively. The results of our study showed that FF is better in agreement with D-LDL-C than Anandaraja’s formula for estimation of LDL-C by calculation though both lead to its underestimation.  相似文献