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391.
392.
In this paper, a mathematical model describing the process of heat transfer in biological tissues for different coordinate system during thermal therapy by electromagnetic radiation is studied. The boundary value problem governing this process has been solved using Galerkin’s method taking B-polynomial as basis function. The system of ordinary differential equation in unknown time variable, thus obtained, is solved by homotopy perturbation method. The effect of thermal conductivity, antenna power constant, surface temperature, and blood perfusion rate on temperature for different coordinates are discussed. It has been observed that the process is faster in spherical symmetric coordinates in comparison to axisymmetric coordinate and faster in axisymmetric in comparison to Cartesian coordinate.  相似文献   
393.
Helicoverpa armigera Nuclear Polyhedrosis Virus (HearNPV) was isolated from the larva, obtained from four different geographic locations in India. All the HearNPV isolates appeared clear, irregular, six sided in outline with rounded edges; phase bright under phase contrast microscope; but varied in size, bioefficacy and restriction profiles. Anand isolate had largest mean diameter, highest frequency of large polyhedral inclusion bodies and gave highest total percent mortality with lowest LC50 and LT50 followed by Surat, Patancheru and Junagadh isolates. Mortality rate of Anand and Surat isolates projected two peaks at two different time intervals pointing at the presence of more than one genotype in the same host origin. Restriction digestion analysis produced many unique fragments for each isolates proving that variation existed between the four isolates. These studies have clearly demonstrated that baculoviruses are very diverse, and that this diversity occurs at a range of scales from between isolates collected from the same host species, to between caterpillars collected at the same site and, from the current study, within variants collected from within an individual larva. The efficacy of such geographic isolates can be greatly improved by a deeper knowledge of their physical, chemical and biological properties. The knowledge can be applied for strain selection of the viruses from wild populations which would prove useful to develop NPVs desirable for biopesticides.  相似文献   
394.
This study investigated the effect of a 30-cm covering of finished compost (FC) on survival of Escherichia coli O157:H7 and Salmonella spp. in active static and windrow composting systems. Feedstocks inoculated with E. coli O157:H7 (7.41 log CFU/g) and Salmonella (6.46 log CFU/g) were placed in biosentry tubes (7.5-cm diameter, 30-cm height) at three locations: (i and ii) two opposing sides at the interface between the FC cover layer (where present) and the feedstock material (each positioned approximately 10 cm below the pile''s surface) and (iii) an internal location (top) (approximately 30 cm below the surface). On specific sampling days, surviving populations of inoculated E. coli O157:H7 and Salmonella, generic E. coli, and coliforms in compost samples were determined. Salmonella spp. were reduced significantly within 24 h in windrow piles and were below the detection limit after 3 and 7 days at internal locations of windrow and static piles containing FC covering, respectively. Likewise, E. coli O157:H7 was undetectable after 1 day in windrow piles covered with finished compost. Use of FC as a covering layer significantly increased the number of days that temperatures in the windrows remained ≥55°C at all locations and in static piles at internal locations. These time-temperature exposures resulted in rapid reduction of inoculated pathogens, and the rate of bacterial reduction was rapid in windrow piles. The sample location significantly influenced the survival of these pathogens at internal locations compared to that at interface locations of piles. Finished compost covering of compost piles aids in the reduction of pathogens during the composting process.  相似文献   
395.
Molecular Biology Reports - Natural polysaccharides cellulose, hemicelluloses, inulin etc., galactooligosaccharides (GOS), and fructooligosaccharides (FOS) play a significant role in the...  相似文献   
396.
Cation sensing behaviour of a pyrrole‐based derivative (2‐hydroxyl 3 methyl 6 isopropyl benzaldehyde}‐3,4‐dimethyl‐1H‐pyrrole‐2‐carbohydrazide (receptor 3) has been explored and is found to be selective towards Zn2+ over a variety of tested cations. The receptor 3 has shown high selectivity and sensitivity towards Zn2+ over the other alkali, alkaline earth and transition metal ions. In the presence of Zn2+, absorption band of receptor 3 has shown the red shift. The sensing behaviour has been suggested to continue via enhancement process which has further been supported by UV‐vis absorption and theoretical density functional theory (DFT) calculations indicating the formation of a 1:1 complex between the pyrrole based receptor 3 and Zn2+. The present work is presenting a highly selective dual channel colorimetric sensor for zinc with great sensitivity. The developed sensor was successfully applied to image intracellular Zn2+ in living cells. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
397.
398.
Nef is an HIV-1 accessory protein that directly contributes to AIDS progression. Nef is myristoylated on the N-terminus, associates with membranes, and may undergo a transition from a solution conformation to a membrane-associated conformation. It has been hypothesized that conformational rearrangement enables membrane-associated Nef to interact with cellular proteins. Despite its medical relevance, to our knowledge there is no direct information about the conformation of membrane-bound Nef. In this work, we used neutron reflection to reveal what we believe are the first details of the conformation of membrane-bound Nef. The conformation of Nef was probed upon binding to Langmuir monolayers through the interaction of an N-terminal His tag with a synthetic metal-chelating lipid, which models one of the possible limiting cases for myr-Nef. The data indicate that residues are inserted into the lipid headgroups during interaction, and that the core domain lies directly against the lipid headgroups, with a thickness of ∼40 Å. Binding of Nef through the N-terminal His tag apparently facilitates insertion of residues, as no insertion occurred upon binding of Nef through weak electrostatic interactions in the absence of the specific interaction through the His tag.  相似文献   
399.
Evaluations of genetic diversity in domestic livestock populations are necessary to implement region‐specific conservation measures. We determined the genetic diversity and evolutionary relationships among eight geographically and phenotypically diverse cattle breeds indigenous to west‐central India by genotyping these animals for 22 microsatellite loci. A total of 326 alleles were detected, and the expected heterozygosity ranged from 0.614 (Kenkatha) to 0.701 (Dangi). The mean number of alleles among the cattle breeds ranged from 7.182 (Khillar) to 9.409 (Gaolao). There were abundant genetic variations displayed within breeds, and the genetic differentiation was also high between the Indian cattle breeds, which displayed 15.9% of the total genetic differentiation among the different breeds. The genetic differentiation (pairwise FST) among the eight Indian breeds varied from 0.0126 for the Kankrej–Malvi pair to 0.2667 for Khillar–Kenkatha pair. The phylogeny, principal components analysis, and structure analysis further supported close grouping of Kankrej, Malvi, Nimari and Gir; Gaolao and Kenkatha, whereas Dangi and Khillar remained at distance from other breeds.  相似文献   
400.
The sugars will eventually be exported transporters (SWEET) family of transporters in plants is identified as a novel class of sugar carriers capable of transporting sugars, sugar alcohols and hormones. Functioning in intercellular sugar transport, SWEETs influence a wide range of physiologically important processes. SWEETs regulate the development of sink organs by providing nutritional support from source leaves, responses to abiotic stresses by maintaining intracellular sugar concentrations, and host–pathogen interactions through the modulation of apoplastic sugar levels. Many bacterial and fungal pathogens activate the expression of SWEET genes in species such as rice and Arabidopsis to gain access to the nutrients that support virulence. The genetic manipulation of SWEETs has led to the generation of bacterial blight (BB)-resistant rice varieties. Similarly, while the overexpression of the SWEETs involved in sucrose export from leaves and pathogenesis led to growth retardation and yield penalties, plants overexpressing SWEETs show improved disease resistance. Such findings demonstrate the complex functions of SWEETs in growth and stress tolerance. Here, we review the importance of SWEETs in plant–pathogen and source–sink interactions and abiotic stress resistance. We highlight the possible applications of SWEETs in crop improvement programmes aimed at improving sink and source strengths important for enhancing the sustainability of yield. We discuss how the adverse effects of the overexpression of SWEETs on plant growth may be overcome.  相似文献   
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