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61.
Glutamate is an important excitatory signal in the hypothalamus for the steroid-mediated preovulatory gonadotropin surge. Steroids may exert this action by regulating glutamate receptor levels or glutamate release, or both. Work in our laboratory found no changes in NMDA and kainate receptor binding in the hypothalamus of castrated or castrated plus steroid-replaced male and female rats. Likewise, we found that NMDA and kainate binding did not change over the onset of puberty in the female rat. A competitive quantitative RT-PCR assay using exogenous internal standards was used to measure NMDAR1, GluR1, and beta-actin mRNAs levels. NMDAR1 and GluR1 expression was examined in the preoptic hypothalamic area and in the medial basal hypothalamus at Postnatal Days 10, 15, 20, 25, 30, 32, 34, 36, 40, and 63. A transient increase in GluR1 mRNA levels in the preoptic hypothalamic area was observed on Day 20, with all other time points showing comparable levels. NMDAR1 levels in the POA and medial basal hypothalamus did not change significantly at any of the time points; in contrast, however, AMPA receptor binding levels were increased in the hypothalamus at the time of puberty in the female rat. Thus, in addition to the previously reported elevation of glutamate release rates in the hypothalamus at the time of puberty, AMPA receptors may also be elevated and play a role in mediating glutamate regulatory effects on the timing of puberty in the female rat. 相似文献
62.
In this study, automation of the circuit board assembly process is considered using artificial neural networks with knowledge-based systems. Basic issues in achieving intelligent control that can adapt to changing conditions in the assembly process are discussed. The feasibility of using neural networks for pattern recognition and optimum component insertion sequence generation is examined. The study provides a basic foundation for designing a conceptual architecture for adaptive intelligent control of circuit board assembly. Real-time testing of component recognition is conducted using adaptive resonance theory (ART 1) as a neural network paradigm. 相似文献
63.
A new method of evaluation of the elastic property deterioration due to accumulated damage is suggested and experimentally verified. It is based on the explicit correlations between two groups of anisotropic properties – conductivity and elasticity, recently established for porous/microcracked materials with anistropic microstructures. An experimental study of fatigue has been done to verify the theoretical predictions. The electrical resistance and Young's modulus are measured as functions of the number of loading cycles in the standard fatigue tests. The agreement between the theoretical predictions and the direct experimental data is better than 10% in all cases. The results allow one to use measurements of the electric resistance to estimate the damage accumulated in methal structures and the decrease of the elastic modulus. 相似文献
64.
With an alarmingly increased rate of deterioration in reinforced concrete structures due to durability performance, efforts are being made to quantify in situ performance. Performance is a function of time and it is related to degradation and the parameters influencing it. Although state-of-the-art modeling of various deterioration mechanisms is available in the literature, evaluation of the influence of various deterioration mechanisms that decrease performance with time is difficult. However, in situ condition documentation, survey, and assessment of deteriorated structures reflect the resultant deterioration process and also helps in validation of experimental and theoretical methods of performance evaluation. In this research, a systematic in situ condition documentation, survey, and assessment of water tank structures has been done based on an empirical damage scale similar to that suggested in the literature and a bilinear graphical deterioration model for such water retaining structures in a semitropical region like India is presented on the basis of case studies. 相似文献
65.
66.
Mahesh C. Bhardwaj 《Materials Research Innovations》1997,1(3):188-196
This paper describes unusual applications of ultrasound that are based upon recent advances in transduction efficiency in
air and gaseous media. Piezoelectric transducer devices – capable of generating extremely high intensity ultrasound in ambient
air up to 5 MHz – have been successfully developed and tested. This is in addition to the obvious uses for gas analysis, remote
sensing, liquid level, gap, and thickness measurement, and proximity analysis. These new generation transducers make it possible
to analyze solids and liquids not only non-destructively, but also without physically contacting the test sample. Among various
applications to the non-destructive characterization (NDC) of industrial materials, we also describe the feasibility of a
forensic application. This concerns the detection of objects such as knives, guns, contraband drugs, dead bodies, etc., hidden
inside false compartments or walls.
Received: 15 October 1997 / Accepted: 24 October 1997 相似文献
67.
Sangappa S.?S.?Mahesh R.?SomashekarEmail author G.?Subramanya 《Journal of Polymer Research》2005,12(6):465-472
Microstructural parameters of varieties of silk fibers, like C.nichi, Pure Mysore Silk (PMS), Hosa Mysore (HM) and Nistari, have been determined by Fourier method of Warren using wide angle X-ray scattering (WAXS) data. Exponential, Lognormal, Reinhold functions for the column length distributions have been used for the determination of microstructural parameters. The goodness of the fit and the consistency of the results suggest the exponential distribution gives much better results in the analysis of fiber diffraction even though lognormal distribution has been widely used to estimate the similar stacking faults in metal oxide compounds. Estimated micro-structural parameters have been compared with parameters of other silk fibers like, Hosa Mysore, Pure Mysore Silk (PMS) and Nistari as a comparison of their molecular maps shows a wide contrast between them. 相似文献
68.
Polarographic reduction of some coupled product of acetyl acetone with aryl diazonium chloride takes place in a single 4-electron transfer, giving a diffusion controlled irreversible waves in B.R. buffers of pH range 2–11.8. The reduction in these compounds takes place at the ---NH---N=C bond. Effect of various cations, anions, surfactant and solvent percentage on the reduction has been discussed. 相似文献
69.
Mahesh Gupta Nissreen Abu‐Ghannam Eimear Gallaghar 《Comprehensive Reviews in Food Science and Food Safety》2010,9(3):318-328
ABSTRACT: Barley is the basic raw material for brewing. Its chemical composition, brewing, and technological indices are highly determinative for the beer quality and the economical efficiency of the brewing process. Barley is rich in protein, carbohydrates, dietary fibers, minerals, and vitamins. The presence of nonstarch polysaccharides as mixed linkage (1‐3),(1‐4)‐β‐d ‐glucans and arabinoxylans together with the enzymes are responsible for barley modification. Malting is a complex process that involves many enzymes; important ones are α‐amylase, β‐amylase, α‐glucosidase, and limit dextrinase. During the process of malting and brewing, the by‐products left after separation of the wort are rich in protein, fibers, arabinoxylans, and β‐glucan. This review summarizes and integrates barley grain with respect to nutritional, functional, and compositional changes that take place during malting and brewing. It also explores in‐depth the several by‐products obtained after brewing and their potential for various food applications. Barley brewing by‐products offer an opportunity for cereal‐based baked and extruded products with acceptable sensory and nutritional characteristics. 相似文献
70.
Priyal Sharma Mahesh Kumar Saini Jagdish Prasad Vinod Singh Gour 《Journal of surfactants and detergents》2019,22(2):403-408
Balanites aegyptiaca (L.) Del. is a widely distributed xerophytic multipurpose tree. The mesocarp of the fruit of B. aegyptiaca has detergent properties due to the presence of saponins. The stability potential of this biosurfactant at varying pH, temperature, and salinity has not been explored so far. In the present study, the relative surface tensions of five different concentrations of the biosurfactant were studied at different temperatures, salinity, and under pH conditions. This study reveals that this biosurfactant retains its activity over a wide range of pH (3–11) and at high salinity (7% NaCl). It is a thermostable cationic surfactant; surfactant activity was recorded even at 100 °C with the lowest relative surface tension of 0.47. High oil displacement (18.00 mm) was observed when studied with petrol. This biosurfactant was found to have a high emulsification index (E24) of 70% with mustard oil. These results indicate that biosurfactant derived from B. aegyptiaca may find use in a wide range of sectors such as textile, food, cosmetics, oil recovery, and healthcare under a wide range of physical and chemical conditions. It offers an efficient, economically viable, and plant-derived alternative to synthetic detergents and adds a way to maintain a sustainable environment. 相似文献