Thin shell wormhole due to dyadosphere of a charged black hole

To explain Gamma Ray Bursts, Ruffini argued that the event horizon of a charged black hole is surrounded by a special region called, the Dyadosphere where electric field exceeds the critical value for $e^+$ $e^-$ pair production. In the present work, we construct a thin shell wormhole by performing a thought surgery between two dadospheres. Several physical properties of this thin shell wormhole have been analyzed.Comment: 10 pages, 2 figures. Accepted in Mod.Phys.Lett.

Glyphosate in waters and soils from genetically modified canola cultivation in Parkes, NSW, Australia

Investigations were conducted of farmland from the Parkes region of New South Wales, Australia, cultivated with genetically modified canola, involving the determination of glyphosate (N-(phosphonomethyl)glycine) concentrations in water and soils, and its sorption. The soils are classified as loam under the USDA system (clay 13.8-15.8%, silt 39-43%, sand 41.2-47.2%). Firstly, a low-cost fluorometric method was developed for the analysis of glyphosate in waters and soils, calibrated against analytical standards and spectrophotometric and enzyme-linked immunosorbent assay (ELISA) methods. Soil and water samples were then collected using the NEPM sampling protocol into glass containers, chilled and analysed within two weeks. The samples were collected in multiple episodes, taking account of glyphosate and pesticide crop applications. The soil and water physical and chemical properties were characterised, and glyphosate levels were determined. Field concentrations of glyphosate ranged between 0.01 - 0.067 mg/L in water and 0.10 - 0.575 mg/kg in soil. The aqueous levels lie below Australian and international drinking water guidelines, but reach a Canadian freshwater guideline. Glyphosate levels varied with time of application and rainfall events. Glyphosate sorption isotherms were also constructed by batch tests on several soils, and were fitted with Freundlich and Langmuir isotherms. Desorption tests indicated 25% to 58% of soil glyphosate is extractable by 0.1M KH2PO4

Some new class of Chaplygin Wormholes

Some new class of Chaplygin wormholes are investigated in the framework of a Chaplygin gas with equation of state $p = - \frac{A}{\rho}$, $A>0$. Since empty spacetime ($p = \rho = 0$) does not follow Chaplygin gas, so the interior Chaplygin wormhole solutions will never asymptotically flat. For this reason, we have to match our interior wormhole solution with an exterior vacuum solution i.e. Schwarzschild solution at some junction interface, say $r = a$. We also discuss the total amount of matter characterized by Chaplygin gas that supplies fuel to construct a wormhole.Comment: 14 pages, 12 figures, Accepted for publication in Mod.Phys.Lett.

Mountain-Shaped Coupler for Ultra Wideband Applications

This paper demonstrates a novel mountain-shaped design for a compact 3-dB coupler operating at ultra-wideband (UWB) frequencies from 3.1GHz to 10.6 GHz. The proposed design was accomplished using multilayer technology in which the structure is formed by three layers of conductors interleaved by a layer of substrate between each conductor layer. Simulation was carried out using CST Microwave Studio; the result was then compared with results from rectangular and star-shaped couplers that implemented the same technique. The results obtained show that the proposed new coupler has better performance compared to both rectangular and star-shaped coupler designs in terms of return loss, isolation, and phase difference. The coupler was fabricated and measured; the measurement results satisfactorily agree with the simulation results

Purification and characterization of cyclodextrin glucanotransferase from alkalophilic Bacillus sp. G1

A cyclodextrin glucanotransferase (CGTase) was successively purified by ammonium sulphate precipitation, and affinity chromatography on a-CD (epoxy)-Sepharose 6B column. The specific activity of the CGTase was increased approximately 2200-fold, from 8.43 U/mg protein to 18,866 U/mg protein. SDS-PAGE showed that the purified CGTase was homogeneous and the molecular weight of the purified CGTase was about 75 kDa. The molecular weight of the enzyme that was estimated by gel filtration under native condition was 79 kDa. This has indicated that Bacillus sp. G1 CGTase is a monomeric protein. The isoelectric point (pI) of the enzyme was about 8.8. Characterization of the enzyme exhibited optimum pH and temperature of 6.0 and 60 8C, respectively. The enzyme was stable from pH 7.0 to 9.0 and retained its high activity up to 60 8C. However, in the presence of 20 mM Ca2+, the purified CGTase is able to prolong its thermal stability up to 70 8C. CGTase was strongly inhibited by ZnSO4, CuSO4, CoCl2, FeSO4, FeCl3 and EDTA. Km and Vmax for the purified enzyme were 0.15 mg/ml and 60.39 mg bcyclodextrin/( ml min), respectively, with soluble starch as substrate. In cyclodextrin production, tapioca starch was found to be the best substrate used to produce CDs. The enzyme produced g- and b-CD in the ratio of 0.11:0.89 after 24 h incubation at 60 8C, without the presence of any selective agents

Arid hydrological modeling at Wadi Alaqiq, Madinah, Saudi Arabia

Madinah is one of the urban centers that have experienced several devastating floods during the past 50 years. The objectives of this study are to estimate the flood hydrograph and peak discharge in the Wadi Alaqiq in Madinah and its major sub-catchments based on daily rainfall distribution. Daily annual maximum records are chosen for rainfall distribution in the study area. Wadi Alaqiq is located in the western part of the Madinah city and consists of five major sub-catchments, namely, Aqiq, Ruwawah, Reem, Al-Yutmah and Annaqi. The HEC-HMS and modified Talbot models are applied to estimate design flood for various average recurrence intervals (ARI). The analysis involves two stages, where stage one is concerned with modeling of the Wadi Alaqiq sub-catchment and comparison of the peak flow values obtained by previous studies and empirical formulae based on rainfall distribution analysis. In the second stage, the HEC-HMS is run separately for the five sub-catchments of Wadi Alaqiq. The model parameter values are then used to simulate for 25-year, 50-year and 100-year flood hydrographs. The HEC-HMS model is used to analyze the hydrologic behaviour of the wadi catchments. Initial and constant rate loss method is used to determine the hydrologic loss and the excess rainfall was transformed using the Clark\x92s Unit Hydrograph. The peak flow simulations are very close with reported values and those derived by modified Talbot. Also, the peak discharges are applied to model discharges from the HEC-HMS and modified Talbot equations of the five sub-catchments for a set of selected return periods. The direct runoff ratio for Madinah region in wadis Al-Yutmah, Annaqi, Aqiq, Reem and Ruwawah ranged from 25 to 28 of the total rainfall. This is due to topography condition, wadi catchment area and the use of predicted maximum daily rainfall results. The model results are reasonable for rainfall-runoff application and can be used for wadi corridor management in arid region