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A simulation based novel and unique approach of controlling and modulating the threshold voltage sensitivity of a short channel surrounding gate MOSFET biosensor is investigated for improved biosensing applications. Different results show that the biosensor with symmetric doping is more sensitive to charged and neutral biomolecules when compared with the asymmetric doping. Threshold voltage sensitivity and subthreshold slope sensitivity of 4.5 and 0.44 have been obtained which shows the significance of doping attributed sensitivity. It is so find that sensitivity increases on increasing drain to source voltage because of stronger horizontal electric field across the channel. A remarkable percentage change due to the doping variation shows the improved biosensing action in terms of threshold voltage change and subthreshold slope change.

A series of diphenylarsenic(III) and triphenylarsenic(V) derivatives of heterocyclic dithiocarbamates of the type: and [where X = > CH2 (Pipdtc), >CH–CH3 (4-MePipdtc), >O (Morphdtc), >N-CH3 (N-MePzdtc), and > NH (Pzdtc)] [n = 1 or 2] have been synthesized by reactions of diphenylarsenic(III) chloride and triphenylarsenic(V) dibromide with the sodium salt of heterocyclic dithiocarbamates in 1 : 1 and 1 : 2 M ratios, respectively, in refluxing benzene. All these newly synthesized compounds have been characterized by their elemental analyses, molecular weight measurements, and ESI mass studies. Structures of the compounds have been proposed on the basis of IR, 1H, and 13C NMR spectral data which suggest anisobidentate mode of bonding.

Planners aim to understand, analyze and influence the variety of forces—social, economic, cultural, legal, political, ecological, technological, aesthetic and so forth shaping the built environment. The present study focuses on the impact of urbanization on air quality in Jaipur city, ‘Pink City’. It is noted that the concentration of respirable suspended particulate matter (RSPM) in residential, commercial and industrial areas of the city are more than the prescribed air quality norms. In fact, the concentration of RSPM in residential and commercial areas of the city is more than the industrial area. With increasing population and growing pollution, we cannot ignore the ill effects of planning on the environment.

To evaluate the effect of Parkinsonia aculeata. Linn. (Caesalpiniaceae) on male reproductive function and fertility, the ethanol crude extract of its stembark was administered orally to male rats at the dose levels of 50, 100 and 200 mg/rat per day for 60 days. A dose-dependent response was found after this treatment. The body weights were not affected, whereas the weights of reproductive organ decreased significantly after this treatment. Significant (p < 0.001) suppression of cauda epididymal sperm count and motility was observed. Fertility was decreased in this treatment by 100% in Parkinsonia aculeata.–treated rats. The testicular cell population, that is, primary (preleptotene, pachytene) and secondary spermatocytes, were reduced significantly. A significant decline was also noticed in seminiferous tubular diameter and differential count of Leydig cells. Oral administration of this drug at all the dose levels did not alter the blood and serum profiles, whereas testosterone level of serum was ...

Oral administration of a methanolic extract of Cressa cretica. Linn. (Rundati) (Convolvulaceae) (whole plant) at a dose level of 100 mg/kg/day for a period of 60 days led to a significant decrease in the weight of testis, epididymis, seminal vesicle, and ventral prostate. Cressa cretica. reduced the fertility of male rats by 100%. There was a marked reduction in the number of primary spermatocytes, secondary spermatocyte, and spermatids. Sertoli cell counts as well as the cross-sectional surface area were significantly decreased. Leydig cell nuclear area and the number of mature Leydig cells were also significantly decreased. The protein, sialic acid, glycogen, and cholesterol content of the testis, the fructose in the seminal vesicle, and protein and sialic acid in the epididymis were significantly decreased. Serum testosterone levels were also reduced after Cressa cretica. treatment. The RBC and WBC counts, hemoglobin, hematocrit, blood sugar, serum cholesterol, phospholipids, triglyceride, and ...

The present study was undertaken to evaluate the antifertility activity of the active principle, i.e. lupeol acetate, isolated from benzene extract of Alstonia scholaris in male albino rats. The treatment with lupeol acetateat the dose level of 10 mg/rat/day did not cause any significant change in the body weights, but significant reduction in the weight of reproductive organs, i.e. testes, epididymides, seminal vesicle and ventral prostate, was observed. Testicular sperm count, epididymal sperm count and motility were found significantly declined when compared with controls, which resulted in reduction of male fertility by 100%. Arrest of spermatogenesis was noted at various stages with production of primary spermatocytes (preleptotene and pachytene), secondary spermatocytes and step-19 spermatids were decreased by 52.36, 54.91, 55.67 and 69.65%, respectively. The seminiferous tubules appeared reduced in size by 24.62%. Cross-sectional surface area of Sertoli cells as well as their counts were found to be significantly depleted. Leydig cell nuclear area and number of mature Leydig cells were decreased by 27.65 and 35.47%. Biochemical parameters of tissues i.e. protein, sialic acid, glycogen and cholesterol content of testes and seminal vesicular fructose also showed significant reduction.

Oral administration of Pueraria tuberosa. D.C. root extract to male rats (100 mg/rat per day) for the period of 60 days did not cause body weight loss, whereas the weights of testes, epididymides, seminal vesicle, and ventral prostate were significantly reduced. The production of step-19 spermatids was reduced by 63.7% in P. tuberosa.–treated rats. The population of preleptotene spermatocytes and secondary spermatocytes were decreased by 61 and 72%, respectively. The seminiferous and Leydig cell nuclear area were reduced significantly (p

Oral administration of saponins isolated from Albizia lebbeck bark at the dose level of 50 mg/kg/b.w. per day for 60 days to male rats brought about a significant decrease in the weights of testes, epididymides, seminal vesicle and ventral prostate. The production of round spermatid was reduced by 73.04% in Albizia lebbeck treated rats. The population of preleptotene spermatocytes and spermatogonia were reduced by 65.07% and 47.48% and secondary spermatocytes by 73.41%, respectively. Cross sectional surface area of Sertoli cells as well as the cell counts were found to be depleted significantly. Leydig cell nuclear area and number of mature Leydig cells were decreased by 57.47% and 54.42%, respectively. Sperm motility as well as sperm density were reduced significantly. Albizia lebbeck reduced the fertility of male rats by 100%. There were no significant changes in RBC and WBC count, haemoglobin, haematocrit and glucose in the blood and cholesterol, protein, triglyceride and phospholipid in the serum. The protein, glycogen and cholesterol contents of the testes, fructose in the seminal vesicle and protein in epididymides were significantly decreased. Histoarchitecture of the testes showed vacuolization at primary spermatocytes stage. Highly reduced seminiferous tubular diameter and increased intertubular space were also observed when compared to controls.

The treatment of α-amyrin acetate given orally in male albino rats at the dose level of 10 mg/rat/day for 60 days did not cause any significant loss in their body weights but the weights of reproductive organs, i.e., testes, epididymides, seminal vesicle and ventral prostate decreased in a significant manner when compared to controls. Sperm motility as well as sperm density were reduced significantly, resulting in complete suppression of fertility. A marked decline in the germ cell population was noticed. Populations of preleptotene, pachytene, secondary spermatocytes and step-19 spermatid were declined by 48.77, 63.29, 53.16 and 64.02%, whereas spermatogonial germ cell count did not show any statistically significant reduction. Leydig cell nuclear area and mature Leydig cell counts were significantly reduced when compared with controls. The seminiferous tubular diameter, cross-sectional surface area and counts of the Sertoli cells were also decreased significantly. The RBC and WBC counts, the levels of h...

Oral administration of Opuntia dillenii phylloclade extract to male rats caused a significant decrease in the weights of testes (P < 0.001), epididymides (P < 0.01), seminal vesicle (P < 0.001) and ventral prostate (P < 0.01). The production of spermatid was reduced by 88.06% in Opuntia treated rats. The populations of preleptotene spermatocytes and spermatogonia were reduced by 59.7 and 61.65% and secondary spermatocytes by 63.32%, respectively. The cross sectional surface area of Sertoli cells was decreased significantly. The seminiferous tubule and Leydig cell nuclear area were reduced significantly (P < 0.001) when compared to controls. Motility of the spermatozoa was reduced significantly. Opuntia reduced the fertility of male rats by 100%.

The antifertility activity of organoantimony(III) complexes PhSb[RC(NC6H4S)CH2(NC6H4S)CR′] {R' = CH3 (R1) and R = R' = CF3 (R2)} derived from corresponding sterically hinlered bifuinctional tetradentate ligands in the male rats was determined. The administration of compounds R1 and R2 at the dose level of 20 mg/kg. b. wt. siignificantly reduced the weights of testes and epididymides. Auxiliary glands showed a significant reduction after the treatment of compound R1 only. Treated animals showed a notable depression of spermatogenesis. The preleptotene spermatocytes were decreased by 76.19 and 47.06; the secondary spermatocytes by 87.4% and 54.87337; and the step-19 spermatids by 72.9 and 46.77% respectively, following the compound R1 and R2 treatment. Reduced sperm count and motility resulted in 100% negative fertility in both the treated groups. A significant fall in the content of various biochemical parameters of eproductive tissues was observed after R1 and R2 treatment in comparison to controls.

A biochemical investigation was carried out on the relative presence of some enzymes of the Krebs cycle and of the associated energy metabolism in various fractions (namely, cyst wall, cyst fluid and zoites) of sarcocysts of Sarcocystis fusiformis from the oesophageal muscles of naturally infected Indian water buffalo (Bubalus bubalis). Except for malate dehydrogenase, the activities of aconitase, isocitrate dehydrogenase, succinate dehydrogenase and fumarase were beyond detectable limits, pointing to a non-functional Krebs cycle in the cysts of this parasite. The activities of adenosine triphosphatase and cytochromes were lowest in cyst fluid and were maximally depicted by cyst wall and zoites.

Three hundred (300) unsexed day old ‘CARIBRO CROSS’ broiler chicks were distributed randomly into three treatment groups T1(control), T2 (probiotic supplemented in the feed) and probiotic supplemented in the water (T3) having 6 replicates in each treatment. Two replicates of each group contain 16 birds each and the rest four of each group contain 17 birds each. The probiotic contained Lactobacillus acidophilus, Lactobacillus bulgaricus, Lactobacillus plantarum, Streptococcus faecium, Bifidobacterium bifidus and Saccharomyces cerevisiae. The probiotic was incorporated at the rate of 100 g/tonne of feed during starter phase (0–4 weeks) and 50 g/tonne of feed during finisher phase (5–7 weeks) in feed probiotic group. However, the probiotic was given at the rate of 1 g/L of water during first week of age and thereafter 1 g/4L of water up to 7 weeks of age in water probiotic group. The basal diet was formulated for starter (23.46% CP, 2800 ME Kcal/Kg) and finisher phase (20.07% CP, 2900 ME Kcal/kg) separately. The chicks consumed significantly (p 0.05). It was concluded that probiotic supplementation reduce the feed consumption of CARIBRO CROSS chicks.

Eighteen lactating crossbred cows (HF × Jersey × Kankrej) yielding 10 to 12 L of milk daily and 7–59 days in milk were divided into three groups of six animals each. The cows under T1 were fed control diet (compound concentrate mixture + dry fodder + green fodder), in T2, control diet + bypass fat supplement (200 g/h/d) and in T3, control diet + unprotected oil (170 g/h/d). There was no difference in DMI, CPI, DCPI and TDNI in the three groups of cows. Ether extract digestibility was higher (P

A biochemical study was conducted to assess the relative presence of some enzymes of gluconeogenesis in various fractions—the cyst wall, cyst fluid and zoites—of sarcocysts of Sarcocystis fusiformis obtained from the oesophageal muscles of naturally infected Indian water buffalo ( Bubalus bubalis ). The activities of fructose 1,6-diphosphatase and malic enzyme were beyond detectable limits. Phosphoenol pyruvate carboxykinase (PEPCK) activity was maximally present in the zoites, whereas glucose 6-phosphates activity was highest in the cyst wall. PEPCK seemed to play a crucial role in carbon dioxide fixation metabolism.

In this paper, for the first time, a two-dimensional (2D) analytical drain current model for sub-100 nm multi-layered gate material engineered trapezoidal recessed channel (MLGMETRC) MOSFET: a novel design is presented and investigated using ATLAS and DEVEDIT device simulators, to mitigate the large gate leakages and increased standby power consumption that arise due to continued scaling of SiO2-based gate dielectrics. The twodimensional (2D) analytical model based on solution of Poisson-s equation in cylindrical coordinates, utilizing the cylindrical approximation, has been developed which evaluate the surface potential, electric field, drain current, switching metric: ION/IOFF ratio and transconductance for the proposed design. A good agreement between the model predictions and device simulation results is obtained, verifying the accuracy of the proposed analytical model., {"references":["S.A. Campbell, D.C. Gilmer, X. Wang, M. Hsieh, H-S. Kim, W.L.\nGladfelter and J. Yan , \"MOSFET transistors fabricated with high\npermittivity TiO2 dielectrics\" IEEE Trans. Electron Devices vol. 44,\npp.104-109, (1997).","W. Tsai et a,l \"Performance comparison of sub 1 nm sputtered TiN\nHfO2 nMOS and pMOSFETs\" IEDM Tech., Dig. 311-314, (2003).","H. Kimura, J. Mizuki, S. Kamiyama and H. Suzuki, \"Extended x-ray\nabsorption fine structure analysis of the difference in local structure of\ntantalum oxide capacitor films produced by various annealing methods\"\nAppl. Phys. Lett. Vol. 66, pp.2209-2211, (1995).","J-L Autran, D. Munteanu, M. Houssa, K. C. Coulie and A. Said,\n\"Performance degradation induced by fringing field-induced barrier\nlowering and parasitic charge in double-gate metal-oxide\nsemiconductor field-effect transistors with high-ê dielectrics\" Japan. J.\nAppl. Phys. Vol. 44, 8362-6, (2005).","S.J. Lee, C.H. Choi, A. Kamath, R. Clark and D.L. Kwong, \"\nCharacterization and reliability of dual high-k gate dielectric stack\n(poly-Si-HfO2-SiO2) prepared by in situ RTCVD process for systemon-\nchip applications\" IEEE Electron Device Lett. Vol. 24, 105-107,\n(2003).","T. Kauerauf, B. Govoreanu, R. Degraeve, G. Groeseneken and H. Maes,\n\"Scaling CMOS: finding the gate stack with the lowest leakage current\"\nSolid-State Electron. Vol. 49, 695-701, (2005).","B.Cheng, M. Cao, R. Rao, A. Inani, P.V. Voorde, W.M. Greene, J.M.C.\nStork, Z. Yu, P.M. Zeitoff and J.C.S. Woo , \"The impact of high-k gate\ndielectrics and metal gate electrodes on sub-100 nm MOSFETs\" IEEE\nTrans. Electron. Devices Vol. 46, pp. 1537, (1999).","J. Zhang, J.S. Yuan and Y. Ma \"Modeling short channel effect on highk\nand stacked gate MOSFETs\" Solid-State Electron. Vol.44, pp.\n2089, (2000).","P.Malik, S.P.Kumar, R.Chaujar, M.Gupta, R.S.Gupta, \"GATE\nMATERIAL ENGINEERED-TRAPIZIODAL RECESSED CHANNEL\nMOSFET FOR HIGH-PERFORMANCE ANALOG AND RF\nAPPLICATIONS\", Microwave and optical technology letters, Vol.52,\nmarch 2010.\n[10] P.H. Bricout and E. Dubois \"Short-channel effect immunity and current\ncapability of sub-0.1-micron MOSFETs using a recessed channel\" IEEE\nTrans. Electron. Devices Vol.43, pp.1251 (1996).\n[11] H. Ren and Y. Hao \"The influence of geometric structure on the hotcarrier-\neffect immunity for deep-sub-micron grooved gate PMOSFET\nSolid-State Electron\". Vol.46, pp. 665 (2002).\n[12] ATLAS: 3-D and DEVEDIT: 3D Device Simulator SILVACO\nInternational (2002).\n[13] X.J. Zhang, H.X. Ren, Q. Feng and Y. Hao, Chin. J. Semiconductors,\nVol.25, pp. 441, (2004) (in chinese)\n[14] N.D. Arora, R.Rios, C-L Huang and K. Raol,\"PCIM: A Physically\nShort-Channel IGFET Model for Circuit Simulation\" IEEE Trans.\nElectron Devices, Vol.41, June 1994."]}

Complexes having the general formula PhAs[SC(NH2):NN:C(R)R′]nCl2-n where (n = 1 or 2) have been synthesized by the reaction of phenylarsenic(III) dichloride with thiosemicarbazones in the presence of triethylamine in stoichiometric ratios in refluxing THF solution. These complexes have been characterized by elemental analyses and molecular weight measurements. Their plausible structure has been assigned on the basis of spectral (IR, 1H and 13C NMR) studies.

The interaction of the sodium salts of thiosemicarbazones with diphenylantimony chloride in 1:1 molar ratio in benzene solution lead to the formation of derivatives, Ph2Sb[SC(NH2)NN: C(R)R′] where R = H; R′ [dbnd] C6H5, CH3OC6H4, C6H5CH[dbnd]CH, and R′ [dbnd] CH3; R′[dbnd]C6H5, CH3OC6H4, C6H4CH3, respectively. The resulting complexes have been characterised on the basis of elemental analyses and molecular weight determination. The mode of bonding of the ligands with the metal atom has been proposed on the basis of I.R., 1H and 13C NMR studies. All these ligands are found to behave as monofunctional bidentate moiety in these complexes.

Effect of fibrolytic enzyme supplementation on nutrients utilization of sheep was studied. Twelve male Patanwadi sheep (12–15 month) were randomly divided in two groups of 6 each. Sheep were fed rations containing 50% wheat straw and 50% compound concentrate mixture. A fibrolytic exogenous enzyme @ 0.025% was added to the ration of animal fed TMR. At the end of 14 weeks experimental period, animals were kept on digestion trial and three animals of each group were used for rumen fermentation analysis. There was no difference in final body weight between the groups due to enzyme treatment. There was non-significant difference on intake of dry matter and organic matter and also digestibility of DM, OM, CF and EE were not affected by treatment. However, the digestibility of CP and NFE were observed significantly (p 0.05) which was somewhat lower in T2 in comparison to T1. It could be concluded that fibrolytic enzyme have no effect on feed intake, body wt gain, digestibility except protein utilization.

Methanolic extract of Albizia lebbeck bark when administered orally at the dose level of 100 mg/rat/day to male rats of proven fertility for 60 days did not cause any significant loss in their body weights but the weights of reproductive organs, i.e. testis, epididymides, seminal vesicle and ventral prostate were decreased in a significant manner when compared to controls. Sperm motility as well as sperm density were reduced significantly which resulted in reduction of male fertility by 100%. Marked decline in the germ cell population was noticed. Population of preleptotene, pachytene, secondary spermatocytes and step-19 spermatid were declined by 60.86%, 65.81%, 71.56% and 66.55%, respectively. Cross-sectional surface area of sertoli cells as well as the cells counts were found to be depleted significantly. Leydig cells nuclear area and number of mature Leydig cells were decreased by 60.03% and 51.56%, respectively. Serum testosterone levels showed significant reduction after A. lebbeck extract feeding. Oral administration of the extract did not affect red blood cell (RBC) and white blood cell (WBC) count, haemoglobin, haematocrit and glucose in the blood and cholesterol, protein, triglyceride and phospholipid in the serum. In conclusion, A. lebbeck bark extract administration arrests spermatogenesis in male rats without noticeable side effects.

Summary Oral feeding of male rats with plumieride (15 mg/rat/day) for the period of 60 days did not cause any significant change in the body weight of treated rats. However, the weights of testes, epididymides, seminal vesicle and ventral prostate were significantly reduced when compared to control values. The production of step-19 spermatids was reduced by 87.26% in plumieride treated rats. The population of preleptotene and pachytene spermatocytes were decreased by 64.26% and 55.13% respectively. Spermatogonia and sertoli cell population was also affected. Plumieride treatment resulted in an arrest of spermatogenesis without any systemic side effect. Sperm motility as well as sperm density was reduced significantly. The number of mature Leydig cells was decreased and complete suppression of fertility was observed. A significant fall in the protein and sialic acid contents of the testes, epididymides, seminal vesicle and ventral prostate as well as glycogen content of testes was also noticed. Fructose in seminal vesicle was lowered whereas testicular cholesterol was elevated. There was no significant change in RBC and WBC count, haemoglobin, haematocrit and sugar in the whole blood and total protein, cholesterol, phospholipid and triglycerides in the serum. Conclusion: Plumieride administration arrests spermatogenesis in male rats without noticeable side effects. For the clinical use more experiments should be carried out in a phased programme.

Textile waste water released from dyeing and printing industries situated in Sanganer, Jaipur (India), brought about inhibition of spermatogenesis in male rats. Water analysis showed the presence of heavy metals at more than permissible limits. Oral administration of waste water to the rats at the dose level of 26.6 ml kg(-1) body wt. significantly reduced the weights of testes, epididymides and seminal vesicle. Treated animals showed a notable depression of various stages of spermatogenesis. The production of spermatids was inhibited by 70.8% in waste-water-treated rats. The populations of spermatogonia, preleptotene spermatocytes and secondary spermatocytes were decreased by 67.2, 71.1 and 73.2%, respectively. The total number of Sertoli cells was affected after waste water treatment. Reduced sperm count and motility resulted in treated groups. A significant fall in the content of various biochemical parameters of reproductive tissues was observed after water treatment.

Recently, a review has already been made on the synthetic contraceptive agents whereas this review embraces the natural contraceptives upto year 2001 with 355 references. It also includes the isolation of their active principles, methods of analysis of active ingredients through TLC, HPLC, their side effects and pharmacological action.

This paper evolves analytically, for the first lime an absolute expression for temperature dependent short-channel threshold voltage reduction and temperature coefficient of threshold voltage of a thin film fully depleted SOI MOSFET. The model, applicable in the enhanced range of temperature (25/spl deg/C

Sixty patients with type III injuries (open fractures) of the tibia were treated in a prospective fashion by combined orthopaedic and plastic surgical schemes based on the principles of early radical cleaning, a second-look operation, and early coverage of soft tissue defects with an appropriate local or distant flap. Stabilization of fractures was achieved by external fixation in most cases and patients were allowed to walk within 4–8 weeks (partial weight bearing). Bony union was achieved in 23.4 weeks. The mean hospital stay was 3.5 weeks. Limb salvage was achieved in all cases and there were no major complications.

Two 100 kW solar photovoltaic power plants have been installed in the State of Uttar Pradesh (UP), India, for the Non-Conventional Energy Development Agency (NEDA) of UP. In the absence of prior experience on such large capacity solar PV power plants, an experimental pilot PV power plant of 25 kW capacity was installed to gain hands-on experience; the lessons learnt were made use of while installing the two power plants. This paper briefly describes the features of the two power plants, the developmental approach adopted based on "building block philosophy" with 25 kW system as the basic unit with the attendant advantages. It includes the indigenous design and development effort made for grid connected operation and most importantly the special design features incorporated to ensure a very high degree of safety and protection so necessary in rural areas with predominantly nonliterate users. The paper concludes with some important lessons learnt from both the technical and logistics points of view for guiding the installation of similar such plants in the remote rural areas in India and other developing countries in the future.

An investigation on the relative presence of some protein metabolic enzymes, namely aspartate aminotransferase (AST), alanine aminotransferase (ALT), NAD+ and NADP+ dependent glutamate dehydrogenase (GLDH) and arginase in cyst wall (CW), cyst fluid (CF) and zoite (ZP) fractions of the sarcocysts of Sarcocystis fusiformis in the oesophageal muscles of Indian water buffalo was carried out. Both the transaminases were present in all the fractions of the cyst, although in variables amounts. There was a higher level of AST activity than of ALT activity. AST activity was the highest in ZT, whereas ALT activity was at a maximum in the CF fraction. The levels of activity of NAD+ and NADP+ dependent GLDH and arginase remained beyond detectable limits. The study revealed that the intermediates of carbohydrate metabolism are linked to protein metabolism by transaminases. The possibility of concomitant removal of ammonia and its subsequent incorporation into the urea cycle is ruled out in this parasitic protozoan.

A comparative biochemical study on some enzymes of glycogenolysis, glycolysis and the hexose monophosphate shunt pathway in various fractions (cyst wall, cyst fluid and zoites) of the sarcocysts of Sarcocystis fusiformis from the oesophageal muscles of naturally infected Indian water buffalo (Bubalus bubalis) was carried out. The pattern and the magnitude of enzymatic activity differed markedly in these fractions. Phosphorylase, hexokinase, aldolase and pyruvate kinase showed their highest levels of activity in the zoites fractions, whereas lactate dehydrogenase was the highest in cyst fluid. Alcohol dehydrogenases were non-detectable. Glucose 6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase were localized in the cyst wall only. Zoites were considered to be the most active metabolic sites for glucose breakdown.

The simultaneous effects of radial and rotational inertia on the performance of an externally pressurized gas-lubricated circular thrust bearing was studied. Pressure depressions due to the effect of various bearing parameters were determined. The theoretical results obtained were compared with the experimental results of Tang and Gross. There is an improvement in the pressure depression and thereby a reduction in the loss of load capacity in the bearing which is beneficial for bearing performance.

The first extensive homologous series of phenolic derivatives exhibiting mesomorphic properties, 4(4-n-alkoxybenzoyloxy)benzylidene-4”-aminophenols(I), has been synthesized and their mesomorphic behaviour studied.

A mathematical analysis of the effects of rotation in the lubrication mechanism of hip joints including the porous nature of the cartilage is presented. The exact solution for pressure in the lubricant region is obtained for a short porous journal bearing which represents a simplified model of the hip joint. The load capacity of the joint increases as the rotation parameter increases, indicating that rotation aids the normal functioning of the joint. The results support experimental observations.

The analysis presented here is an attempt to study the influence of couple stresses on the lubricating film of a hydrostatic stepped thrust bearing using Stokes' couple stress fluid model. This also includes the effects due to circumferential velocity caused by rotation of the rotor. An approximate expression for the pressure distribution is obtained by using an “energy integral method”. A weaker flow rate and higher load capacity are observed for small values of the couple stress parameter. These are the most significant findings which can be applied in the selection of a better lubricant.