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11.
L. Plantarum NCIM 2084 cells are homofermentative, essentially producing lactic acid as the main end product of glucose fermentation. Prolonged use through repeated batch fermentation with the cells of L. plantarum immobilized on chitosan treated polypropylene matrix showed a shift in the metabolic pathway from the homofermentative to heterofermentative, accompanied by morphological changes in immobilized cells from the normal rod shape to the coccoid shape. These changes appear to be related to a shift in the bacterial cell metabolism, resulting in a decrease in lactic acid yields. 相似文献
12.
Rajashekhar V Ballari Asha Martin Lalitha R Gowda 《Journal of the science of food and agriculture》2013,93(2):340-347
BACKGROUND: Brinjal is an important vegetable crop. Major crop loss of brinjal is due to insect attack. Insect‐resistant EE‐1 brinjal has been developed and is awaiting approval for commercial release. Consumer health concerns and implementation of international labelling legislation demand reliable analytical detection methods for genetically modified (GM) varieties. RESULTS: End‐point and real‐time polymerase chain reaction (PCR) methods were used to detect EE‐1 brinjal. In end‐point PCR, primer pairs specific to 35S CaMV promoter, NOS terminator and nptII gene common to other GM crops were used. Based on the revealed 3′ transgene integration sequence, primers specific for the event EE‐1 brinjal were designed. These primers were used for end‐point single, multiplex and SYBR‐based real‐time PCR. End‐point single PCR showed that the designed primers were highly specific to event EE‐1 with a sensitivity of 20 pg of genomic DNA, corresponding to 20 copies of haploid EE‐1 brinjal genomic DNA. The limits of detection and quantification for SYBR‐based real‐time PCR assay were 10 and 100 copies respectively. CONCLUSION: The prior development of detection methods for this important vegetable crop will facilitate compliance with any forthcoming labelling regulations. Copyright © 2012 Society of Chemical Industry 相似文献
13.
14.
Lalitha Oruganti 《电子产品世界》2005,(12):66-71
简介 信号完整性是高速系统设计的关键因素.较差的信号完整性会导致工程成本增加,延缓产品发布,降低产品收益.在当今要求产品能够及时面市的半导体市场上,忽略信号完整性可能会造成高达几百万美元的代价.高速系统中如何保持信号完整性无疑取决于对FPGA的选型. 相似文献
15.
In case of spatial multi spectral images, such as remotely sensed earth cover, there could be many classes in one entire frame covering a large spatial stretch, because of which meaningful dimensionality reduction cannot perhaps be realizable without trading off with the quality of classification. However most often one would encounter in such images, presence of only a few classes in a small neighborhood, which would enable to devise a very effective dimensionality reduction around that small neighborhood identified as a block. Based on this theme a new method for dimensionality reduction is proposed in this paper.
The method proposed divides the image into uniform non-overlapping windows/blocks. The few features that are essential in discriminating classes in a window are identified. Clustering is performed independently on each of the blocks with the reduced set of features. These clusters in the blocks are later merged to obtain an overall classification of the entire image. The efficacy of the method is corroborated experimentally. 相似文献
16.
Dielectric constant (ɛ), dielectric loss (tan δ) and conductivity (σ) for K2Zn2(SO4)3 and (NH4)2 Mg2(SO4)3 have been measured over the frequency range 100 Hz — 100 kHz and in temperature range 30°C — 400°C. The values of static
dielectric constant at room temperature are 7.67 and 4.80 for K2Zn2(SO4)3 and (NH4)2 Mg2(SO4)3 respectively. The plots of log σ against reciprocal temperature at different frequencies of these samples merge into a straight
line beyond 250°C and the activation energies calculated in this region are found to be 0.67 eV and 1.98 eV for K2Zn2(SO4)3 and (NH4)2 Mg2(SO4)3 respectively. 相似文献
17.
In this paper we propose a methodology to mine concepts from documents and use these concepts to generate an objective summary of all relevant documents. We use the conceptual graph (CG) formalism as proposed by Sowa to represent the concepts and their relationships in the documents. In the present work we have modified and extended the definition of the concept given by Sowa. The modified and extended definition is discussed in detail in section 2 of this paper. A CG of a set of relevant documents can be considered as a semantic network. The semantic network is generated by automatically extracting CG for each document and merging them into one. We discuss (i) generation of semantic network using CGs and (ii) generation of multi-document summary. Here we use restricted Boltzmann machines, a deep learning technique, for automatically extracting CGs. We have tested our methodology using MultiLing 2015 corpus. We have obtained encouraging results, which are comparable to those from the state of the art systems. 相似文献
18.
Nagaraju R. Haritha L. Sekhar K. Chandra Shareefuddin Md. Lalitha G. Kumar K. Vijaya 《Journal of Materials Science: Materials in Electronics》2022,33(18):14397-14408
Journal of Materials Science: Materials in Electronics - To investigate the structural, optical and spectroscopic properties for possible applications in optical and shielding materials, the... 相似文献
19.
A microstrip patch filtenna inspired by defected ground structure (DGS) is presented in this article. It uses modified split ring resonator and capacitance loaded strip as a radiating element. The presented structure is incorporated with a pair of double U‐shaped DGS (DU‐DGS) to obtain filtering characteristics. The width of DU‐DGS plays a vital role in selecting attenuation poles of the filter as well as for the filtenna circuit. The separation distance between the DU‐DGS also affects the resonant frequency of the structure. Both radiation and filtration can be performed through a single structure, otherwise known as filtenna. The physical size of the proposed filtenna in terms of guided wavelength is 2.465λg × 1.160λg × 0.116λg at 10.8 GHz, and is comparatively less to others reported, so is considered as a superior feature. The presented filtenna possesses impedance bandwidth of 700 and 1800 MHz at 10.8 and 16.6 GHz, which covers standards of X‐ and Ku‐band, respectively. So, this can be referred to as dual band filtenna. The radiation pattern shows omnidirectionality in both E and H planes at resonance. 相似文献
20.
Dimerisation of olefins catalysed by K10-montmorillonite clays 总被引:1,自引:0,他引:1
K10- as well as cation-exchanged montmorillonite clays are found to catalyse efficiently the dimerisation of trans-stilbene, 1,1-diphenylethylene and -methylstyrene, in a reaction involving carbocationic intermediates. 相似文献