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The practice of tripping the generator breakers immediately following a boiler/turbine trip exposes a steam turbine generator to a potentially damaging overspeed operating condition. This paper describes the use of the sequential trip mode as a means of minimizing the exposure to possible unit damage following a boiler/turbine trip. Included is a comparison of the application of devices used by several major steam turbine generator manufacturers in accomplishing sequential tripping of the unit. This paper also discusses the differences in the devices used in implementing the tripping scheme and those applied as backup motoring protection. Additionally, the paper provides guidance in the selection of which functions should and should not be used to initiate sequential tripping.

The uniqueness of the electrical environment (asynchronous connection to power system, variable frequency operation, and harmonics) on the output of adjustable speed drives (ASDs) requires special consideration to be given to the motor protection. The Working Group has investigated and addressed these concerns. This paper announces the report on the findings of this activity and the recommendations made to the motor protection engineer. The full report can be found at www.pes-psrc.org under Published Reports.

The present work describes dynamic uptake of the antibiotic drug ciprofloxacin hydrochloride (CH), by using a cost-effective agricultural by-product . sawdust (SD). The sawdust was characterised by FTIR and SEM analysis. The sorbent particles were highly porous with average pore diameter of nearly 10 ƒÊm. The optimum pH and solid/liquid ratio for sorption of CH were found to be 5.8 and 2.0, respectively. The dynamic drug uptake data was applied to various kinetic models and their order of fitness was found to be pseudo second order > Elovich equation > power function model, as indicated by their regression values. The experimental equilibrium uptake values (qe) were in close agreement with those evaluated from the pseudo second order equation for initial sorbate concentrations of 10 and 20 mgE.-1 at 33‹C. The drug uptake mechanism was found to be attractive non-electrostatic interactions, involving H-bonding interactions between H atoms and other electronegative species such as F, O and N of the drug molecule. The mechanism is discussed on the basis of pHpzc of sawdust and zwitterionic nature of drug CH. Mass transfer analysis was carried out using the drug uptake data obtained with sorbate concentrations of 10 and 20 mgE.-1. The used sorbent could be regenerated using 1.0 molE.-1 HCl solution with a regeneration efficiency of nearly 85%.

In majority of individuals blood pressure rises in the early morning hours, which lead to serious cardiovascular complications. Formulation of pulsatile system makes it possible to deliver drug at definite period of time when symptoms of the disease condition are most critical. The purpose of the present work was to develop pulsatile release tablet of losartan potassium for chronotherapy in hypertension. The prepared system consisted of a core tablet coated with versatile and safe hydrophilic cellulosic ethers such as, hydroxypropyl methylcellulose, hydroxypropyl cellulose and sodium carboxy methylcellulose to produce burst release after predetermined lag time. Various formulation factors were studied through series of test and in vitro dissolution study. It was found that core tablets containing superdisintegrant failed to produce burst drug release pattern while effervescent agent was able to do so. Results also reveal that coating composition and coating level affects lag time. Formulation containing effervescent agent in core and coated with 200 mg hydroxypropyl cellulose provide lag time of 4.5 h with 73% drug release in 6 h that followed a sigmoidal release pattern. These values were close to the desired objective of producing lag time of 5â??6 h followed by fast drug release. This approach can thus provide a useful means for timed release of losartan and is helpful for patients with morning surge.

Hydrogels containing silver nanoparticles have a variety of biomedical applications because of the excellent compatibility of hydrogels with biological molecules, tissues, cells, and exceptional antibacterial properties of silver nanoparticles. Here we report the design and development of various hydrogel networks that can be employed as matrices to grow and form metal nanoparticles. This behavior is achieved because of their enormous hydrophilic groups and free space between gel networks that extend not only stabilization but also participate in reduction process. This chapter provides an in-depth review of various hydrogel systems that can be employed for nanoparticles synthesis.

Genetics, combinatorial chemistry and automation have greatly increased the number of therapeutic programs and compounds in the pharmaceutical industry pipeline. The increase in the number of new molecular entities (NMEs) has led to changes in the process by which compounds are evaluated during drug discovery and selected for clinical development. There is a need for the earlier determination of the absorption, distribution and elimination characteristics of NMEs, and drug metabolism scientists are working to develop higher-throughput in vitro screens for absorption, distribution and metabolism of compounds. These screens rely on advancements in analytical technology and molecular biology, and frequently use human or 'humanized' tissues. Throughput to determine in vivo pharmacokinetics has also progressed with the use of mixture dosing and sample pooling methods. The continued refinement of in vitro and in vivo ADME methods will allow the industry to evaluate the absorption and disposition characteristics of larger numbers of molecules and will ultimately allow the prediction of human pharmacokinetics at early stages of the development process.

This paper serves as an introduction to the Guide for the Protection of Shunt Reactors (IEEE Std C37.109-2006). It briefly describes the material contained in the Guide and presents some examples. Those with further interest should obtain the complete document.

Peak expiratory flow rate (PEFR) variability follows a specific pattern in asthmatics as well as in healthy individuals. There is scarcity of data for Indian healthy subjects. The PEFR (L/min.) was measured with Wright's portable peak flow meter at 05:00, 8:00, 11:00, 14:00, 17:00, 20:00 and 23:00 hours in 42 healthy, non-smoking adults of age group between 18-26 years. The variability of PEFR revealed a circadian pattern. PEFR levels tend to increase from morning at 5:00 hours till evening at 17:00 hours, with peak PEFR in evening at 17:00 hours, after which there was a progressive fall in PEFR levels, till morning 5:00 hours. This study provides the preliminary reference data of circadian pattern of PEFR in healthy individuals.

This review article is focused on the various approaches that have been made to synthesize metal nanoparticles with predetermined shape, size, and fair stability. Due emphasis has been given on polymer stabilized nanoparticles. In addition use of other varieties of stabilizers like inorganic salts, organic compounds, organic solvent, biological molecules, etc. have also been discussed. Finally, formation of two and three-dimensional nanostructures like nanowires, nanodiscs, nanoprisms has also been revealed.

Inflammation of the female reproductive tract increases susceptibility to HIV-1 and other viral infections and, thus, it becomes a serious liability for vaginal products. Excessive release of proinflammatory cytokines may alter the mucosal balance between tissue destruction and repair and be linked to enhanced penetration and replication of viral pathogens upon chemical insult. The present study evaluates four surface-active microbicide candidates, nonoxynol-9 (N-9), benzalkonium chloride (BZK), sodium dodecyl sulfate, and sodium monolaurate for their activity against human sperm and HIV, and their capacity to induce an inflammatory response on human vaginal epithelial cells and by the rabbit vaginal mucosa. Spermicidal and virucidal evaluations ranked N-9 as the most potent compound but were unable to predict the impact of the compounds on vaginal cell viability. Interleukin (IL)-1 release in vitro reflected their cytotoxicity profiles more accurately. Furthermore, IL-1 concentrations in vaginal washings correlated with cumulative mucosal irritation scores after single and multiple applications (P0.01), showing BZK as the most damaging agent for the vaginal mucosa. BZK induced rapid cell death, IL-1 release, and IL-6 secretion. The other compounds required either more prolonged or repeated contact with the vaginal epithelium to induce a significant inflammatory reaction. Increased IL-8 levels after multiple applications in vivo identified compounds with the highest cumulative mucosal toxicity (P0.01). In conclusion, IL-1, IL-6, and IL-8 in the vaginal secretions are sensitive indicators of compound-induced mucosal toxicity. The described evaluation system is a valuable tool in identifying novel vaginal contraceptive microbicides, selecting out candidates that may enhance, rather than decrease, HIV transmission.

Tyrosine phosphorylation and its upregulation by cAMP have been associated with capacitation and motility changes of spermatozoa. In the present study, washed spermatozoa were incubated for 6 h in protein-supplemented complete medium with or without kinase inhibitors to verify whether upstream activation of protein kinase A is indispensable for tyrosine phosphorylation and motility changes to occur in capacitating human spermatozoa. H89, a specific protein kinase A inhibitor, significantly inhibited the activity of sperm protein kinase A. However, this inhibition did not alter capacitation-related tyrosine kinase activation. Tyrosine phosphorylated proteins, motion parameters and the incidence of phosphotyrosine-immunoreactive spermatozoa were decreased only slightly. Conversely, genistein, a tyrosine kinase inhibitor which inhibited sperm tyrosine kinase but not protein kinase A, significantly reduced all the parameters studied. Spermatozoa incubated with cAMP and pentoxifylline showed a rapid enhancement of tyrosine phosphorylation and some of the sperm motion parameters, particularly hyperactivation. Inclusion of H89 reduced cAMP stimulation of tyrosine kinase, and tyrosine phosphorylation and motion parameters were reduced almost to basal values. Treatment with genistein reduced tyrosine kinase activity, especially in the soluble fraction of sperm extracts. A decrease in tyrosine phosphorylation of soluble proteins, 105, 81, 55 and 48 kDa, correlated with a significant reduction in sperm motion parameters. Hyperactivation was reduced by tenfold. Tyrosine phosphorylated proteins in the insoluble fraction and the incidence of tyrosine phosphorylated-positive spermatozoa were not reduced markedly. Upstream protein kinase A activation may be a facilitatory rather than an indispensable step in the capacitation-induced tyrosine phosphorylation mediating motility changes in human spermatozoa. Triton-x100 soluble tyrosine phosphorylated proteins, more than their insoluble counterparts, appear to be involved in the modulation of human sperm motion characteristics.

This paper presents the results of a project performed to (a) determine the severity of insulator contamination in nuclear power generating station, and (b) compare and evaluate different types of room temperature vulcanized (RTV) silicone rubber coatings available for improving the contamination performance of the porcelain insulators in the station. Cap and pin suspension insulators coated with four different formulations of RTV silicone rubber and uncoated insulators, were evaluated over a 3 year period. Periodic measurements of ESDD, NSDD, contaminant analysis, flashover testing and material analysis were performed. Results indicate that the RTV coatings evaluated can provide a significant improvement in the contamination performance, are resistant to environmental conditions prevailing in the station, and exhibit similar electrical and weathering, characteristics.

A -1027 bp to + 108 bp region of Na-K-ATPase alpha3 gene promoter has been searched for the presence of thyroid response elements (TRE). Computer analysis of this sequence using a consensus TRE sequence revealed the presence of four putative TRE rich regions referred to as regions I (-636 to -457 bp), II (-218 to -106 bp), III (-106 to -6 bp) and IV (-6 to +108 bp). Cotransfection of the luciferase linked full length construct as well as constructs progressively devoid of the TRE rich regions in Cos1 cells revealed that regions I and III are positively regulated by T3 whereas there are some sequences in region II which can suppress the positive regulatory effect of region III but not of region I. TRE IV seems to have no functional role. EMSA of the three functional TRE rich regions (I, II and III) showed strong and specific interaction with thyroid hormone receptor (TR) cloned and expressed in baculovirus. The overall results suggest the regulation of Na-K-ATPase alpha3 gene by T3 is complex involving several thyroidal regulatory elements.

Variations in specific activities of the marker enzymes of Sertoli and germ cells during breeding (November-December) and non-breeding (May-June) seasons were investigated in rhesus and bonnet monkeys maintained under laboratory conditions. The marker enzymes selected for testicular cells were-Sertoli cells: beta-glucuronidase, gamma-glutamyl transpeptidase; pre-meiotic germ cells: glucose 6-phosphate dehydrogenase, malate dehydrogenase, alpha-glycerophosphate dehydrogenase; mature germ cells: LDH-X, sorbitol dehydrogenase. Results have indicated significant seasonal variation in marker enzymes only in rhesus testis. Marker enzymes of Sertoli cell increased while those of germ cell decreased significantly during non-breeding season. Marker enzymes of mature germ cells were affected much more drastically than those of the pre-meiotic germ cells.

Mediastinal teratomas usually present in the anterior mediastinum, almost always in contact with the thymus. However, rare cases have also been described in the pericardium and posterior mediastinum. We present one such case of a successfully treated posterior mediastinal teratoma.

In this work, ZnO microparticles were in situ in the chitosan – attached cotton fabric following ‘equilibration – cum - hydrothermal’ approach to yield zinc oxide microparticles loaded cotton (ZOMLC) fabrics. The ZnO microparticles were characterized by surface plasmon resonance (SPR), X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. The ZOMLC fabric showed fair antibacterial action against model bacteria E.coli.

Copper is a normal constituent of the diet and is present in all living matter. It is an important trace metal required for different metabolic processes. Detecting alterations in serum copper has an important role in the early detection and diagnosis of malignancy. Serum copper estimation was conducted on 95 women aged 32-60 using the P.P. Doxidase method. 62 women of varying age and parity had different stages of carcinoma cervix uteri and comprised the study group, while the control group was comprised of 33 non-pregnant women of different ages and parity. Approximately 40% of women in both groups were aged 41-45 years. In the control group, the mean serum copper level of reproductive age women was 118.3 ug% and 111.2 ug% among women of menopausal age. A linear progressive increase of serum copper levels was found in the study group with increasing stages of cervical malignancy. The mean values of stages I, II, III, and IV were 162.2 ug%, 190.64 ug%, 201.78 ug%, and 220.8 ug%, respectively.