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A major detriment to reliable and sustainable operation of rotational equipment has been extensively linked to high thermal loads from frictional dissipation. Frictional dissipation in critical tribological components such as bearings and gears results in lubricant degradation and subsequent subpar thermal performance. In this study, a novel in situ lubricant cooling system is used to provide a continuous cooling of these critical tribo-components. Experiments were conducted using rolling element bearing (REB) and planetary gear system (PGS) sets. The stationary outer race of a REB was used to accommodate a cooling coil in a heat exchange-like arrangement. Similarly, the stationary outer ring of the PGS housed a cooling coil in another heat exchanger-like arrangement. Use of the heat exchanger arrangements assured continuous in situ cooling to remove the heat generated in the tribological REB and PGS. Water was used as the coolant while Amsoil 75W-90 Severe Gear® oil was the lubricant used. Highly conductive copper coils surrounded the REB or PGS and the coolant was circulated through the coils to remove the heat from the outer bearing race and ring gear. The hot lubricant rejects heat by convection into the outer race thereby limiting lubricant degradation. The incidence of wear and premature failure are also minimized. So far results from this experimental study show that heat generation is significantly minimized in bearings and gears when cooled in situ. This preliminary study has offered important insight for more rigorous follow-on studies.Copyright © 2011 by ASME

Cerebral malaria is the most common cause of non-traumatic encephalopathy in the world. The mainstay of therapy is either quinine or artemisinin, both of which are effective antimalarials. The clinical picture of cerebral malaria may persist or even become worse in spite of the clearance of parasites from blood. The death rate is unacceptably high even with effective antimalarials in tertiary care hospitals. The mortality increases in presence of multi organ failure (renal failure, jaundice, respiratory distress, severe anaemia, lactic acidosis, etc.). The pathogenesis of cerebral malaria is multifactorial and includes clogging, sequestration, rosette formation, release of cytokines, cerebral oedema, increased intracranial hypertension, etc. Attempts are made to use adjuvant therapy which will act through alternate mechanisms and address one or more of the pathogenetic processes. In this review, we have discussed the role of corticosteroids, pentoxifylline, desferrioxamine, mannitol and newer agents in the treatment of cerebral malaria. Though the literature on adjuvant therapy in cerebral malaria is large enough, there are a number of shortcomings in the clinical trials, many being open and non randomized or of very small sample size. Further research is of utmost importance through large multicentric, double-blind controlled trials to show the efficacy of any of these drugs.

Sex chromosome abnormalities, such as 47,XXX, 47,XXY, 47,XYY, and 45,X, are relatively common and occur in approximately 1 of 400 births. Sex chromosome tetrasomy and pentasomy are much rarer events. The somatic and developmental consequences of supernumerary sex chromosomes have not been studied adequately. This is especially true of individuals with only supernumerary Y chromosomes. Based on available case reports, the effects of extra Y chromosomes appear not as severe as those of supernumerary X chromosomes. Only two case reports of nonmosaic tetrasomy of the Y chromosome have been published. We evaluated a 30-year-old man with a 49,XYYYY karyotype and assessed his severe physical and mental handicaps (particularly the endocrine abnormalities) and attempted to clarify the effects of extra Y chromosomes on growth, development, and behavior.

To examine factors which may predispose to tooth fracture, and to assess the compressive strengths of foods and sweets which are associated with tooth fracture in vivo.Consecutive dental patients presenting with one or more fractured posterior teeth at the surgeries of three general dental practitioners, over a four-month period.A pro forma was designed to elicit information on the factors associated with tooth fracture and the nature and extent of such fractures. Three general dental practitioners were requested to complete a pro forma for each patient presenting with a fractured posterior tooth over a four-month period. Foods and sweets considered to be associated with tooth fracture were identified and their compressive strengths tested.A total of 129 cases of fractured posterior teeth were recorded, of which 48% occurred in the mandibular arch and 52% in the maxillary arch. In the mandible, 75% of tooth fractures occurred in molars while in the maxillary arch 50% occurred in molars. In 57% of cases assessed, no identifiable causative item was noted. Forty-five per cent of fractures were in teeth which had been restored on three or more surfaces. Compressive forces of 0.16KN to 2.2KN were obtained for food items implicated in tooth fractures.As mesio-occlusodistal restorations were identified as a major predisposing factor to tooth fracture in this study, with mandibular first molar teeth particularly affected, placement of cuspal coverage restorations may be considered to be a justifiable preventative measure in teeth identified as being at risk.

In view of the controversies existing regarding the atherogenic potential of smoking, this study was conducted in 40 healthy young male Cigarette smokers and 40 age and weight matched male non smokers, to find out the difference in the serum lipid profiles of both the groups. Subjects in both the groups were in the age range of 25 and 35 years having no history of alcohol abuse or diseases like diabetes mellitus or obesity. The mean serum total cholesterol (177.3 +/- 32.5 mg/dL) and LDL cholesterol (100.2 +/- 31.0 mg/dL) were significantly higher in smokers (p0.05) whereas mean serum HDL- Cholesterol was (43.2 +/- 5.8 mg/dL) was significantly lower (P0.05). Mean triglyceride (170.8 +/- 59.7 mg/dL) was significantly higher in smokers than in nonsmokers (p0.01). In the fed state the total serum cholesterol level and triglyceride level was increased by 10.4 mg/dL and 51.1 mg/dL respectively in smokers whereas the increase was 4.8 mg/dL and 24.3 mg/dL respectively in nonsmokers. There was less rise of HDL cholesterol (1.9 mg/dL) in smokers as compared to that in nonsmokers (3.4 mg/dL) and in LDL-cholesterol (1.8 mg/dL) in smokers compared to nonsmokers (3.4 mg/dL) in fed state.

Metabolism of the anticancer agent crisnatol was investigated using a human hepatoma cell line, Hep G2, and human liver microsomes. Crisnatol was metabolized extensively by both systems. The TLC/autoradiographic analysis showed that the crisnatol metabolite profile was similar for both systems and the major metabolites were shown to have structural characteristics similar to those formed by the rat. The Hep G2 cells formed three isomeric dihydrodiols; one of these has been identified by GC/MS and 1H-NMR as the crisnatol 1,2-dihydrodiol. Human liver microsomes also formed two isomeric dihydrodiols with 1,2-dihydrodiol as the major isomer and, in addition, produced 1-hydroxycrisnatol. Crisnatol concentrations of 1.3 micrograms/mL completely inhibited the replication of Hep G2 cells as measured by thymidine incorporation and cell growth kinetics and, at this concentration, cell viability decreased by only 35% as determined by vital staining of cells using neutral red dye.

Disposition and metabolism of crisnatol (14C-labeled), a novel antitumor agent, was examined after po and iv administration to rats. After both routes of drug administration, there was rapid elimination of the administered radioactivity in the urine (6-12% of the dose) and feces (81-92% of the dose). The drug appeared to be rapidly absorbed after oral dose and there was substantial "first-pass" metabolism. Analysis of the excreta indicated extensive metabolism of crisnatol by the rat, with the intact compound being the major radiolabeled component in the feces (17-20% of dose). Intact drug was not present in urine. Biotransformation of crisnatol by the rat mainly involves oxidation and conjugation pathways. Hydroxylation and dihydrodiol formation in the chrysene ring and oxidation of the propanediol side chain resulted in the formation of the three major fecal metabolites. The principal metabolite in the urine was also a dihydrodiol. Concentrations of intact drug in each tissue assayed exceeded those in plasma, and in the lungs the tissue/plasma ratio approached 300 and 82 at 2 hr after iv and po doses, respectively.

1. Metabolism of aspirin was studied in 10 human volunteers who took a therapeutic dose (600 mg) by mouth and in nine patients who took aspirin in overdose. 2. Salicyluric acid was the major urinary metabolite in volunteers (63.1 +/- 8.4% of dose in 0-8 h). In overdose patients, salicyluric acid in urine was decreased (30.0 +/- 8.2%, 0-24 h, P less than 0.001) and there was increased elimination of salicyclic acid (34.1%, P less than 0.005), salicyl acyl glucuronide (14.4%, P less than 0.05) and gentisuric acid (5.3%). 3. Metabolism of orally administered 14C-aspirin in rats over a 10-fold dose range (10-100 mg/kg) resulted in excretion of 81-91% dose in urine in the first 24 h. Salicyclic acid was the major urinary metabolite (43-51% dose). Excretion of salicyluric acid decreased with increasing dose, whereas gentisic acid and salicyl phenolic and acyl glucuronides increased. 4. The profile of aspirin metabolites was qualitatively similar in man and rat but there were quantitative differences. Limited capacity to form salicyluric acid was observed in both species. Dependence on this pathway in rat was low and was compensated by increased utilization of other routes; dependence on salicyluric acid formation in man was high and in overdose, compensation by other routes was incomplete.

Fifteen (34.8%) of 43 patients of falciparum malaria screened for urinary abnormalities showed significant proteinuria (greater than 150 mg/24 h), haematuria (greater than 1/HPF) and casts, with or without azotaemia. Light microscopic examination of renal biopsy tissue from 12 patients revealed mesangial and endothelial proliferative change in 8, and acute tubular necrosis in one patient. Immunofluorescence showed IgM alone, or IgG and IgM along with C3, in 7 patients within the mesangium or along the capillary walls. Repeat kidney biopsy after 6 wk in 5 patients revealed no residual pathology indicating the reversible nature of the lesions.

In this paper, the design and construction of a speech entry data logger are described. This equipment consists of a commercially available voice recognition chip set, a bubble memory module, and a supervisory microprocessor. Necessary details on the hardware and software are included for the construction of the equipment. Test results using the equipment are included.

Vier Equisetum-Arten, E. palustre, E. arvense, E. hiemale und E. maximum wurden auf weitere Inhaltsstoffe untersucht.

To assess the effect of sleep on airflow resistance and patterns of ventilation in asthmatic patients with nocturnal worsening, 10 adult subjects (6 asthmatic patients with nocturnal worsening, 4 normal controls) were monitored overnight in the sleep laboratory on two separate occasions. During 1 night, subjects were allowed to sleep normally, whereas during the other night all sleep was prevented. The six asthmatic patients demonstrated progressive increases in lower airway resistance (Rla) on both nights, but the rate of increase was twofold greater (P less than 0.0001) during the sleep night compared with the sleep prevention night. However, overnight decrements in forced expired volume in 1 s (FEV1) were similar over the 2 nights. The asthmatic patients maintained their minute ventilation as Rla increased during sleep, demonstrating a stable tidal volume with a mild increase in respiratory frequency. We conclude that in asthmatic patients with nocturnal worsening 1) Rla increases and FEV1 falls overnight regardless of sleep state, 2) sleep enhances the observed overnight increases in Rla, and 3) sleep does not abolish compensatory ventilatory responses to spontaneously occurring bronchoconstriction.

R.& D.Department Cadila Laboratories, Ghodasar, Ahmedabad -380 008 Bhavan's R.A. College of Science, Khanpur, Ahmedabad-380 001 Manuscriptreceived 20 March 1976,revised 5th November 1976,accepted 10 November 1976 In order to evaluate their anesthetic and anticonvulsant properties, various benzyloxy oxa­mides have been synthesised.

In a study of 144 children aged 1-12 years, attempts were made to assess the ED50 and ED90 of the intravenous induction agent, propofol. The doses required for loss of eyelash reflex and tolerance of facemask, in 50% of unpremedicated children, were 1.6 mg/kg and 2.5 mg/kg respectively. In children premedicated with oral trimeprazine the corresponding values of ED50 were 1.1 mg/kg and 2.0 mg/kg. Doses of 2.8 mg/kg in unpremedicated and 2.0 mg/kg for those who received trimeprazine were required for loss of eyelash reflex in 90% of children. This probably corresponds to an effective induction dose. Pain and movement on induction were common; the incidence was 27% and 21.5% respectively.

A one-dimensional numerical technique is presented herein for determining the surface temperature boundary condition from an in-depth temperature history that is obtained from a single thermocouple in the Space Shuttle orbiter's thermal protection system (TPS). An iterative solution technique is given for solving this inverse heat conduction problem with a multi-material system that has been modeled with unequally spaced nodes. Results are presented for both a test case and an actual flight case (the second flight of the Space Shuttle). Heat flux, backed out from thermocouple temperature, is shown to match angle-of-attack maneuver phasing for an effective thermocouple displacement below the surface. Backed-out heat flux for an effective thermocouple depth is also shown to provide an acceptablc match with surface calorimeter data.

In the reaction of iodine with hydroxylamine it appears that at least two types of reactions proceed simultaneously, one involving absorption and the other, liberation of iodine. Titrations show that the amount of iodine absorbed always reaches a maximum after which the absorption distinctly diminishes. In neutral solution, the liberation of iodine takes place slowly and apparently reaches a definite value in fifteen to thirty minutes. Nitrite appears to be the chief product of the reaction. This is supported by the fact that the maximum amount of iodine absorbed tends to approximate to four atoms of iodine for one molecule of hydroxylamine and never exceeds this limit

In the presence of either neutral salts, basic salts or acids the iodine absorbed increases rapidly and reaches a maximum in about 2-10 minutes after which iodine appears to he liberated at a higher rate than that at which it is absorbed and hence the apparent absorption of iodine falls In neutral solution, the liberation of iodine takes place slowly, although as a general rule neutral salts have no appreciable effect on the course of this reaction The absorption of iodine appears to be fairly rapid and continuously increases with time in the presence of basic salts In the presence of mineral acids, the primary absorption of iodine is very small, being only about 1/5th of that required in the ease of neutral salts The liberation of iodine in the second stage, under these conditions, is more rapid In the presence of acetic acid, the absorption is similar to that in the case of neutral salts The absorp­tion of iodine is slightly more in an atmosphere of carbon dioxide than under ordinary conditions