Converging Cylindrical Shock Waves in a Nonideal Gas With an Axial Magnetic Field

This paper analyses the propagation of converging cylindrical shock waves in a nonidealgas, in the presence of an axial magnetic field. Chester-Chisnell-Whitham’s method has beenemployed to determine the shock velocity and the other flow-variables just behind the shockin the cases, when (i) the gas is weakly ionised before and behind the shock front, (ii) the gasis strongly ionised before and behind the shock front, and (iii) nonionised gas undergoes intenseionisation as a result of the passage of the shock. The effects of the nonidealness of the gas,the conductivity of the gas, and the axial magnetic field have been investigated. It is found thatin the case (i), an increase in the value of parameter ( ) characterising the nonidealness of thegas accelerates the convergence of the shock. In the case (ii), the shock speed and pressurebehind the shock increase very fast as the axis is approached; and this increase occurs earlierif the strength of the initial magnetic field is increased. In the case (iii), for smaller values of theinitial magnetic field, the shock speed, and pressure behind the shock decrease very fast afterattaining a maximum; and for higher values of the initial magnetic field, the tendency of decreaseappears from the beginning. This shows that the magnetic field has damping effect on the shockpropagation. In the case (iii), it was also found that the growth of the shock in the initial phaseand decay in the last phase were faster when it was converging in a nonideal gas in comparisonwith that in a perfect gas. Further, it has been shown that the gas-ionising nature of the shockhas damping effect on its convergence

Intracultural Cognizance of Medicinal Plants of Warangal North Forest Division, Northern Telangana, India

Differences in the traditional botanical knowledge of Koya communities inhabiting Eturnagaram Wildlife Sanctuary (Warangal North Forest Division) are investigated. Eighteen villages (16 within the wildlife sanctuary and two outside it) were selected to test the null hypothesis that there exist no cognitive differences among the ethnic inhabitants in their ability to recognize the plants and recall the vernacular names and medicinal uses since they are recipients of the same dry deciduous forest ecosystem services. The Koyas were found to use as medicine 237 species in 66 angiosperm families. Analyses of data gathered from villagers showed that there is significant intracultural diversity in terms of taxonomic groups and growth forms in regard to utilizing the proximate plant resource for their primary healthcare and disease treatment of pets

Damping and Trapping in 2D Inviscid Fluids

We demonstrate collisionless decay due to phase mixing of a disturbance in an inviscid 2D fluid with sheared flow. Experiments performed on a cylindrical pure electron plasma, which behaves as a 2D inviscid fluid, show that a small amplitude quadrupole excitation (m=2, k=0 mode) decays exponentially. At larger amplitudes, the exponential decay is modulated by bounce motion of fluid elements trapped in the azimuthally traveling wave field, with the bounce frequency proportional to the square root of the excitation amplitude. We also show that the linear decay rate is decreased by the addition of external dissipation. We describe a calculation of the linearized response function

Comparative Study of Sink Node Placement Strategies of Wireless Sensor Network

One of the fundamental design challenges in designing a Wireless Sensor Network (WSN) is to be more maximize the network lifetime, as each sensor node of the network is equipped with a limited power battery. Wireless Sensor Networks are rapidly growing area of research and commercial development. Meanwhile it draws attention of many researchers because of the enormous scope of its applications in numerous areas. A Wireless Sensor Network (WSN) consists of large number of spatially distributed autonomous sensors to monitor physical environment conditions, such as temperature, sound, humidity, pressure, light etc. and pass their data often called raw data through the network to Base Station which is often called Sink. The sink forms the gateway between the WSN and end-user application. In real time applications sensors collect data and transfer to the sink. Generally Sensors have limited range and less battery life. In this paper our main goal is to increase the network life time of sensors and reduce their energy consumption of the network. In this paper two sink placement strategies are implemented along with an existing strategy geographical sink placement strategy (GSP) by placing sink in an appropriate area to cover maximum number no of sensors in the region of an network. The advantages of these two strategies were analyzed and compare with an existing strategy

Morphology and Magnetic Properties of Sulfonated Poly[styrene-(ethylene/butylene)-styrene]/Iron Oxide Composites

α-Fe2O3 structures were initiated in the sulfonated polystyrene block domains of poly[styrene–(ethylene/butylene)–styrene] (SEBS) block copolymers via a domain-targeted in-situ chemical precipitation method. The crystal structure of these particles was determined using wide-angle X-ray diffraction and selected area electron diffraction using a transmission electron microscope (TEM). TEM revealed that for less sulfonated SEBS (10 mole%), nanoparticles were aggregated with aggregate size range of 100–150 nm whereas for high sulfonation (16 and 20 mole% sSEBS) there were needle-like structures with length and width of 200–250 nm and 50 nm, respectively. Dynamic mechanical analyses suggest that initial iron oxide nanoparticle growth takes place in the sulfonated polystyrene block domains. The magnetic properties of these nanocomposites were probed with a superconducting quantum interference device magnetometer at 5 and 150 K as well as with an alternating gradient magnetometer at 300 K. The materials exhibited superparamagnetism at 150 K and 300 K and ferrimagnetism at 5 K

Intergeneric hybridization in pigeonpea. I. Effect of hormone treatments

Attempts to cross Cajanus cajan with Atylosia albicans, A. cajanifolia, A. grandifolia, A. mollis, A. platycarpa, A. sericea and A. volubilis resulted in varying degrees of success. Hormone treatment (gibberellic acid and kinetin) increased pod-set and the number of seeds per pod. Hormone treatment among the unsuccessful crosses delayed bud drop by 3–4 days, which prolonged ovule development. Our results indicate that treatment with hormones helps post-fertilization development and leads to improvement in the rate of crossing succes

Intergeneric hybridization in pigeonpea. II. Effect of cultivar on crossability and hybrid fertility

Eight species of Atylosia hybridized with Cajanus cajan L. Millsp. with varying degrees of success when Cajanus was the female parent. The cultivar of the Cajanus parent influenced both the species crossability and hybrid fertility. Variation in the extent of species crossability and hybrid fertility was less pronounced in Cajanus × Atylosia crosses involving Cajanus cultivars derived from a common female background

Enhancement in production of recombinant two-chain Insulin Glargine by over-expression of Kex2 protease in Pichia pastoris

Glargine is an analog of Insulin currently being produced by recombinant DNA technology using two different hosts namely Escherichia coli and Pichia pastoris. Production from E. coli involves the steps of extraction of inclusion bodies by cell lysis, refolding, proteolytic cleavage and purification. In P. pastoris, a single-chain precursor with appropriate disulfide bonding is secreted to the medium. Downstream processing currently involves use of trypsin which converts the precursor into two-chain final product. The use of trypsin in the process generates additional impurities due to presence of Lys and Arg residues in the Glargine molecule. In this study, we describe an alternate approach involving overexpression of endogenous Kex2 proprotein convertase, taking advantage of dibasic amino acid sequence (ArgArg) at the end of B-chain of Glargine. KEX2 gene overexpression in Pichia was accomplished by using promoters of varying strengths to ensure production of greater levels of fully functional two-chain Glargine product, confirmed by HPLC and mass analysis. In conclusion, this new production process involving Kex2 protease over-expression improves the downstream process efficiency, reduces the levels of impurities generated and decreases the use of raw material

Ternary structure reveals mechanism of a membrane diacylglycerol kinase

Diacylglycerol kinase catalyses the ATP-dependent conversion of diacylglycerol to phosphatidic acid in the plasma membrane of Escherichia coli. The small size of this integral membrane trimer, which has 121 residues per subunit, means that available protein must be used economically to craft three catalytic and substrate-binding sites centred about the membrane/cytosol interface. How nature has accomplished this extraordinary feat is revealed here in a crystal structure of the kinase captured as a ternary complex with bound lipid substrate and an ATP analogue. Residues, identified as essential for activity by mutagenesis, decorate the active site and are rationalized by the ternary structure. The g-phosphate of the ATP analogue is positioned for direct transfer to the primary hydroxyl of the lipid whose acyl chain is in the membrane. A catalytic mechanism for this unique enzyme is proposed. The active site architecture shows clear evidence of having arisen by convergen