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71.
Magnetopriming has emerged as a promising seed-priming method, improving seed vigor, plant performance and productivity under both normal and stressed conditions. Various recent reports have demonstrated that improved photosynthesis can lead to higher biomass accumulation and overall crop yield. The major focus of the present review is magnetopriming-based, improved growth parameters, which ultimately favor increased photosynthetic performance. The plants originating from magnetoprimed seeds showed increased plant height, leaf area, fresh weight, thick midrib and minor veins. Similarly, chlorophyll and carotenoid contents, efficiency of PSII, quantum yield of electron transport, stomatal conductance, and activities of carbonic anhydrase (CA), Rubisco and PEP-carboxylase enzymes are enhanced with magnetopriming of the seeds. In addition, a higher fluorescence yield at the J-I-P phase in polyphasic chlorophyll a fluorescence (OJIP) transient curves was observed in plants originating from magnetoprimed seeds. Here, we have presented an overview of available studies supporting the magnetopriming-based improvement of various parameters determining the photosynthetic performance of crop plants, which consequently increases crop yield. Additionally, we suggest the need for more in-depth molecular analysis in the future to shed light upon hidden regulatory mechanisms involved in magnetopriming-based, improved photosynthetic performance.  相似文献   
72.
Roselle is a bast fiber, and its utilization as a textile fiber for the development of textile products is still scanty. A work has been attempted to develop yarn from Roselle. Fibers were extracted from Roselle bark by decortication and degummed in alkaline medium. The degumming process was optimized based on fiber yield and strength. The degummed fibers were then bleached by the hydrogen peroxide bleaching process. Degummed and bleached fibers were characterized by scanning electron microscope, Fourier transform infrared spectroscopy, and X-ray diffraction analysis. Degumming and bleaching results in enhancement of density, fineness, and brightness of Roselle fiber. A marginal decrease in tenacity of the Roselle fiber was observed after bleaching; however, the strength was not affected by degumming. Fibers were converted into fine yarn in the jute spinning system. The yarn properties inferred that the yarn possessed essential properties for the preparation of apparels and home furnishing.  相似文献   
73.
In this study, a cutting tool is developed from duplex stainless steel (DSS) using the superplastic boronizing technique. The feasibility of the development process is studied, and the cutting performances of the cutting tool are evaluated and compared with commercially available carbide and high-speed steel (HSS) tools. The superplastically boronized (SPB) cutting tool yielded a dense boronized layer of 50.5 µm with a surface hardness of 3956 HV. A coefficient of friction value of 0.62 is obtained, which is lower than 1.02 and 0.8 of the carbide and HSS tools. When tested on an aluminum 6061 surface under dry condition, the SPB cutting tool is also able to produce turning finishing below 0.4 µm, beyond the travel distance of 3000 m, which is comparable to the carbide tool, but produces much better results than HSS tool. Through superplastic boronizing of DSS, it is possible to produce a high-quality metal-based cutting tool that is comparable to the conventional carbide tool.  相似文献   
74.
A hairy root line of Linum album LYR2i was obtained via the genetic transformation of a cotyledon segment of the plant by cocultivating it with Agrobacterium rhizogenes and culturing it in hormone-free B5 Gamborg liquid medium. Characteristic changes in root morphology associated with variations in biosynthetic capabilities were achieved by adding different combinations of phytohormones to the basal medium. A reversible system between hairy roots and its cultures with a diversified morphology was established by including and excluding phytohormones in the basal medium. The medium containing indole 3 acetic acid (IAA) at a concentration of 3 mg/l (MI3) induced thicker root tips and that containing 2,4-dichlorophenoxy acetic acid (2,4-D) at a concentration of 1 mg/l (MD1) induced compact green callus. Podophyllotoxin and 6-methoxypodophyllotoxin content increased by 1.86-fold and 1.45-fold as a result of adding IAA (MI3) and 2,4-D (MD1) to the basal medium, respectively. After regeneration, the hairy roots regained their original morphology and biosynthetic capability on hormone-free basal medium. The transformation status of the regenerated hairy roots was confirmed by PCR analysis.  相似文献   
75.
The theory of generalized thermoelastic diffusion with one relaxation time is employed to study the distribution of temperature, displacement components, stresses, concentration and chemical potential in a semi-infinite medium having an impulsive mechanical load at the origin. Using the joint Laplace and Fourier transforms, the governing equations are transformed into a vector–matrix differential equation which is then solved by the eigenvalue approach. The solution of the problem in the physical domain is obtained numerically using a numerical method for the inversion of the Laplace and Fourier transforms. Results of this work are presented graphically and are compared with the results of generalized thermoelasticity and classical elasticity deduced as special cases.  相似文献   
76.
Neeru Bala  Sunita Rani 《Sadhana》2009,34(6):887-902
Closed-form analytical expressions for the displacements and the stresses at any point of a two-phase medium consisting of a homogeneous, isotropic, perfectly elastic half-space in welded contact with a homogeneous, orthotropic, perfectly elastic half-space due to a dip-slip fault of finite width located at an arbitrary distance from the interface in the isotropic half-space are obtained. The Airy stress function approach is used to obtain the expressions for the stresses and the displacements. The case of a vertical dip-slip fault is considered in detail. The variations of the displacements with the distance from the fault and with depth have been shown graphically.  相似文献   
77.
In this article, fuzzy based rendezvous points selection (FRPS) technique for mobile data gathering in wireless sensor networks is proposed. At beginning, the importance of detected data is categorized into perilous and non-perilous based on the perseverance and time limit of data. Then two Sencars are set up: one for gathering perilous data by visiting straight to the corresponding sensors, the other one for gathering non-perilous data from other sensors. The rendezvous points (RPs) for visiting the Sencars are determined by using fuzzy decision model based on the input parameters energy level, buffer occupancy level, and current load. Based on the output of this model, each sensor is assigned a combined utility value. Then the sensors with high utility values are selected as RPs and the details are broadcast to the respective Sencars.  相似文献   
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In the present investigation, goat prochymosin cDNA was cloned and characterized by sequence analysis. The prochymosin cDNA spanned 1101 nucleotides and was predicted to code for 365 amino acid with a proregion of 42 amino acid. The goat prochymosin cDNA revealed a high degree of homology with respect to nucleotide and amino acid sequence with corresponding to NCBI sequence to goat chymosin at the 99% and 98% levels, respectively, followed by sheep with 98% homology at both the nucleotide and amino acid levels. The least homology of 76% at the nucleotide level and 69% at the amino acid level was observed for the rat sequences. The cDNA fragment containing goat prochymosin was then subcloned in to pET43.1a(+) and expressed as a NusA fusion protein in E.coli which showed low level of milk clotting activity after activation at acid pH.  相似文献   
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