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Field measurements during the Bay of Bengal Monsoon Experiment (BOBMEX-99), data from a deep sea moored buoy, and satellite altimeter were used to describe variability in the hydrographic and meso-scale features in the Bay of Bengal (BoB) during the summer monsoon of 1999. The thermohaline fields showed two regions of upsloping of isopleths centered at 82°E and 84.75°E, ∼110 km and 450 km away from the coast, respectively, followed by downsloping. The upsloping/downsloping of isopleths and the alternating currents was part of cyclonic and anti-cyclonic circulation patterns in the western BoB. In this region, both wind and current were important in the dynamics of coastal upwelling. The observations showed a relationship between the propagating waves and eddy on variability of thermohaline fields. On an annual cycle, four Kelvin waves were observed in the BoB, but only the downwelling Kelvin wave formed during October entered the Arabian Sea. During the monsoon season, four eddies were formed in the western BoB, of which the anticyclonic eddy centered at 15°N, 84°E and the cyclonic eddy centered at 17.5°N, 84.5°E were prominent. The baroclinic instability caused by the opposing currents along the east coast and the wind stress curl favored the formation of eddies. Okhubo-Weiss and Isern-Fontanet parameter confirmed the presence of eddies in the BoB. [ABSTRACT FROM PUBLISHER]

This paper presents a novel technique for representing cost information of a candidate design. The underlying principle is to provide a knowledge-based system for cost modelling that makes the cost effects of design decisions more visible and quickly available to the designer. The development of a hybrid between hierarchical trees and object-oriented knowledge representation environment to represent cost information is shown. The development of an abstract product structure, reusable tree object libraries and an automated system to extract design information needed for estimation from computer-assisted design geometry is discussed. It is shown how the tool provides fast incremental cost fluctuations in response to changes in component geometry. This paper also considers the uncertain quantities present in cost models and analyses cost risk. A case study demonstrating the research applied to a Rolls-Royce aircraft gas turbine engine component is presented. [ABSTRACT FROM AUTHOR]

We describe 94 pathogenic NF1 gene alterations in a cohort of 97 Austrian neurofibromatosis type 1 patients meeting the NIH criteria. All mutations were fully characterized at the genomic and mRNA levels. Over half of the patients carried novel mutations, and only a quarter carried recurrent minor-lesion mutations at 16 mutational warm spots. The remaining patients carried NF1 microdeletions (7%) and rare recurring mutations. Thirty-six of the mutations (38%) altered pre-mRNA splicing, and fall into five groups: exon skipping resulting from mutations at authentic splice sites (type I), cryptic exon inclusion caused by deep intronic mutations (type II), creation of de novo splice sites causing loss of exonic sequences (type III), activation of cryptic splice sites upon authentic splice-site disruption (type IV), and exonic sequence alterations causing exon skipping (type V). Extensive in silico analyses of 37 NF1 exons and surrounding intronic sequences suggested that the availability of a cryptic splice site combined with a strong natural upstream 3′ splice site (3′ss)is the main determinant of cryptic splice-site activation upon 5′ splice-site disruption. Furthermore, the exonic sequences downstream of exonic cryptic 5′ splice sites (5′ss) resemble intronic more than exonic sequences with respect to exonic splicing enhancer and silencer density, helping to distinguish between exonic cryptic and pseudo 5′ss. This study provides valuable predictors for the splicing pathway used upon 5′ss mutation, and underscores the importance of using RNA-based techniques, together with methods to identify microdeletions and intragenic copy-number changes, for effective and reliable NF1 mutation detection. Hum Mutat 28(6), 599-612, 2007. Published 2007 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

We report the prenatal diagnosis of total anomalous pulmonary venous connection to the portal system in a 20-week fetus with right atrial isomerism. The apex of the fetal heart pointed to the left, the fetal stomach was on the right, there was a common atrioventricular valve, the left ventricle was small and the abdominal aorta and inferior vena cava were on the left side; all these features were suggestive of right atrial isomerism. An anomalous vein was connected to the portal vein which ascended above the diaphragm and ended in a confluence of pulmonary veins, posterior to the common atrium. Color Doppler imaging helped confirm the diagnosis of total anomalous pulmonary venous connection. The prenatal findings were confirmed on autopsy. [ABSTRACT FROM AUTHOR]

Henna leaf ( Lawsonia inermis), commonly known as Mehndi is cultivated throughout India and is a very popular natural dye to color hand and hair. It is an integral part of indigenous culture, and is also known for its medicinal value. The effect of 200 and 400 mg/kg body weight of 80% ethanolic extract of the fresh leaves of Lawsonia inermis were examined on drug metabolizing phase-I and phase-II enzymes, antioxidant enzymes, glutathione content, lactate dehydrogenase and lipid peroxidation in the liver of 7 weeks old Swiss albino mice. Also anticarcinogenic potential of Henna leaf extract was studied adopting the protocol of benzo(a)pyrene induced forestomach and 7,12 dimethylbenz(a)anthracene (DMBA)-initiated and croton oil-promoted skin papillomagenesis. Our primary findings reveal the ‘duel-acting’ nature of henna leaf as deduced from its potential to induce only the phase-II enzyme activity, associated mainly with carcinogen detoxification in liver of mice and inhibit the phase I enzyme activities. The hepatic glutathione S-transferase and DT-diaphorase specific activities were elevated above basal (p < 0.005) level by Lawsonia inermis extract treatment. With reference to antioxidant enzymes the investigated doses were effective in increasing the hepatic glutathione reductase (GR), superoxide dismutase (SOD) and catalase activities significantly (from p < 0.05 to p < 0.005) at both the dose levels. Reduced glutathione (GSH) measured as non-protein sulphydryl was found to be significantly elevated in liver (p < 0.005) and in all the extrahepatic organs studied (from p < 0.05 to p < 0.005). Among the extrahepatic organs examined (forestomach, kidney and lung) glutathione S-transferase and DT-diaphorase level were increased in a dose independent manner (from p < 0.05 to p < 0.005). Chemopreventive response was measured by the average number of papillomas per mouse (tumor burden) as well as percentage of tumor bearing animals and tumor multiplicity. There was a significant inhibition of tumor burden in both the tumor model systems studied (from p < 0.01 to p < 0.001). Tumor incidence was also reduced by both the doses used in our experiment in both the model systems. [ABSTRACT FROM AUTHOR]

We present a detailed X-ray study of the microquasar GRS 1915+105 during a variability class transition observed in 2000 June with the Pointed Proportional Counters (PPCs) of the Indian X-ray Astronomy Experiment (IXAE). We supplement this observation with data from the RXTE archives. The source made a transition from a steady low–hard state to a regular oscillatory behaviour in the light curve known as bursts or class ρ (variability classes from Belloni et al.) between 2000 May 11 and 17 and reverted back to the low–hard state on 2000 June 27. A gradual change in the burst recurrence time from about 75 s to about 40 s was observed, which then increased to about 120 s during the ∼40 d of class ρ. The regular bursts disappeared from the X-ray light curves and the class transition was observed to occur within 1.5 h on 2000 June 27 with the PPCs. A correlation is found between the observed quasi-periodic oscillation frequency at 5–8 Hz in the quiescent phase and the average X-ray intensity of the source during the class ρ. We notice a strong similarity between the properties of the source during the class ρ and those during the oscillatory phase of the observations of class α, which contains a long stretch (∼1000 s) of steady low–hard state in the light curve along with the regular periodic bursts. From the timing and spectral analysis, it is found that the observed properties of the source over tens of days during the class ρ are identical to those over a time-scale of a few hundreds of seconds in the class α. Examining the light curves from the beginning of the RXTE/PCA and RXTE/ASM observations, it is found that the change of state from radio-quiet low–hard state to high state occurs through the X-ray classes ρ and α, which appear together during the state transition. It is further inferred that the source switches from low–hard state to the class ρ through the intermediate class α. [ABSTRACT FROM AUTHOR]

Numerous reports have revealed an inverse association between consumption of some selective natural products and risk of developing cancer. In the present study the effect of 250 and 500 mg/kg body weight of Spirulina was examined on drug metabolising phase I and phase II enzymes, antioxidant enzymes, glutathione content, lactate dehydrogenase and lipid peroxidation in the liver of 7-week-old Swiss albino mice. The implications of these biochemical alterations have been further evaluated adopting the protocol of benzo(a)pyrene induced forestomach and 7,12 dimethylbenz(a)anthracene (DMBA) initiated and croton oil promoted skin papillomagenesis. Our primary findings reveal the ‘Monofunctional’ nature of Spirulina as deduced from its potential to induce only the phase II enzyme activities associated mainly with carcinogen detoxification. The glutathione S-transferase and DT-diaphorase specific activities were induced in hepatic and all the extrahepatic organs examined (lung, kidney and forestomach) by Spirulina pretreatment (significance level being from p < 0.05 to p < 0.005) except for the low dose treatment in forestomach. With reference to antioxidant enzymes viz., superoxide dismutase, catalase, glutathione reductase, glutathione peroxidase and reduced glutathione were increased significantly by both the chosen doses of Spirulina from p < 0.01 to p < 0.005. Chemopreventive response was quantitated by the average number of papillomas per effective mouse (tumor burden) as well as percentage of tumor bearing animals. There was a significant inhibition of tumor burden as well as tumor incidence in both the tumor model systems studied. In the skin tumor studies tumor burden was reduced from 4.86 to 1.20 and 1.15 by the low and high dose treatment respectively. In stomach tumor studies tumor burden was 2.05 and 1.73 by the low and high doses of Spirulina treatment against 3.73 that of control. [ABSTRACT FROM AUTHOR]

A few classes of the light curve of the black hole candidate GRS 1915+105 have been analysed in detail. We discover that unlike the previous findings, quasi-periodic oscillations (QPOs) occasionally occur even in the so-called ‘On’ or softer states. Such findings may require a revision of the accretion/wind scenario of the black hole candidates. We conjecture that considerable winds that are produced in ‘Off’ states cool down as a result of Comptonization and fall back to the disc, creating an excess accretion rate and producing the so-called ‘On’ state. After the drainage of the excess matter, the disc goes back to the ‘Off’ state. Our findings strengthen the shock oscillation model for QPOs. [ABSTRACT FROM AUTHOR]

The effect of a uniform magnetic field on Bénard-Marangoni convection in a shallow cavity, with differentially heated side walls, filled with two viscous, immiscible, incompressible an electrically conducting fluids is studied in the presence of a buoyancy force. The fluid-fluid interface and the free surface are assumed to be flat, and the driving forces for the flow are the thermocapillary and the buoyancy forces. Closed-form solutions, under thin layer approximation neglecting the side wall effects, are obtained for the stream function and the temperature. The solutions are obtained in various limiting cases, namely: absence of buoyancy force, absence of thermocapillary force and absence of magnetic field, and they coincide with the results existing in the literature. The velocity is calculated, and the resulting cell patterns are discussed for different values of λ, the ratio of the temperature gradients of surface tension at the interface and the free surface and the Hartmann number. There exist four different flow regimes depending on the values of λ but with reduced convection compared to the non-magnetic case for Marangoni convection. It is observed that it is possible to control the convection in the lower layer by a suitable choice of the magnetic field. [ABSTRACT FROM AUTHOR]

We present results of our analysis of a set of RXTE/PCA observations of X-ray flares/bursts with burst cycle ranging from 30 to 1300 s from theGalactic X-ray transient source GRS 1915+105 during last four years.These flares/bursts can be classified into four types: 1) regular burstswith short burst phase of ∼ 20 s (R1), 2) regular bursts with shortquiescent phase of ∼ 20 s (R2), 3) long regular bursts (R3) withburst cycle ≥ 1000 s, and 4) irregular bursts (IR). For all theobserved bursts, the duration of the quiescent phase is inverselyproportional to the square of the QPO frequency (2–10 Hz). [ABSTRACT FROM AUTHOR]

Recent results on the inner disk oscillations found in GRS 1915+105 are reviewed. QPOs during the low state are used as a marker for such oscillations and the physical picture emerging from a combined X-ray spectral and timing analysis isexamined. The relationship between inner disk oscillations andsynchrotron radio emission is critically evaluated. [ABSTRACT FROM AUTHOR]

Describes the distributions of morphological variability of wheat in eastern Nepal. Regularities in the distribution of barley genotypes; Changes in the frequency of the naked caryopsis character; Collection of 94 populations from 91 sites in a small area; Consideration of a large number of quantitative and qualitative characters of wheat.

Describes the purification, crystallization and preliminary X-ray studies of Mycobacterium tuberculosis ribosome recycling factor. One protein molecule in the asymmetric unit contained in the monoclinic crystals with 52.5 percent solvent content.

Frequencies of sister-chromatid exchanges (SCEs) were measured to study the genotoxicity of the total aqueous extract of betal nut and its tannin on mouse bone-marrow cells . Betal nut aqueous extract and tannin were injected i.p. into mice at doses of 12.5, 25 or 50 μg/g body weight and 50, 100 or 200 μg/g body weight respectively for 5, 10 or 15 days. Betal nut extract induced a dose-related increase in the frequency of SCEs after five daily doses of 12.5, 25 or 50 μg. Significant increases in SCEs were also observed in animals dosed for 10 days with 50 μg/g and for 15 days with 25 or 50 μg/g extract. After five daily doses of 50, 100 or 200 μg/g of betel nut tannin there was no significant induction of SCE. Mice dosed with 200 μg/g tannin for 10 days, or 100 or 200 μg/g for 15 days, showed significant increases in the frequency of SCEs. [ABSTRACT FROM PUBLISHER]

The chemopreventive properties of a Spirulina fusiformis (blue green algae) suspension in olive oil on 7,12-dimethylbenz(a)anthracene(DMBA) induced skin papillomagenesis in female Swiss albino mice are beingreported. A significant reduction in the values of tumor incidence, tumorburden and cumulative number of papillomas was observed in mice treated orallywith Spirulina fusiformis suspension continuously at pre-, peri-and post-initiation stages of papillomagenesis as compared to the controlgroup. Treatment of Spirulina fusiformis suspension by oralgavage for 15 days resulted in a significant decrease in the cytochrome P-450content of the liver (p < 0.01) . Conversely, glutathione S-transferaseactivity was observed to be significantly elevated as compared with the controlgroup (p < 0.1) following treatment with Spirulina fusiformis suspension. [ABSTRACT FROM AUTHOR]