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131.
This paper concentrates on the problem of automated negotiations in e-supply network coordination (e-SNC). Supply network is considered as a collection of agent-mediated decisions and coordination mechanisms in a web-based environment. The proposed agent based coordination model is composed of two negotiator agents and a coordinator agent. The coordination mechanism begins with determining the feasible and most promising partners in the network based on the similarity of profiles. In response to autonomy levels and conflict objectives, the model allows agents to negotiate in a cooperative manner through an iterative process of generating offers for re-establishing global optimality. The dynamic negotiation model is then defined based on the protocol, rule of bargain, proposal generation, and dynamic strategy. To illustrate the model efficiency, a prototype system has been modeled and is compared to the normal tendering mechanism. The validation results confirm the model efficiency in providing coherent decision making in a dynamic environment.  相似文献   
132.
Efficient accumulation of flavonoids is important for increased tolerance to biotic stress. Although several plant defense mechanisms are known, the roles of many pathways, proteins, and secondary metabolites in stress tolerance are unknown. We generated a flavanone 3-hydroxylase (F3H) overexpressor rice line and inoculated Xanthomonas Oryzae pv. oryzae and compared the control and wildtype inoculated plants. In addition to promoting plant growth and developmental maintenance, the overexpression of F3H increased the accumulation of flavonoids and increased tolerance to bacterial leaf blight (BLB) stress. Moreover, leaf lesion length was higher in the infected wildtype plants compared with infected transgenics. Kaempferol and quercetin, which scavenge reactive oxygen species, overaccumulated in transgenic lines compared with wildtypes in response to pathogenic infection, detected by scanning electron microscopy and spectrophotometry. The induction of F3H altered the antioxidant system and reduced the levels of glutathione peroxidase activity and malondialdehyde (MDA) contents in the transgenic lines compared with the wildtypes. Downstream gene regulation analysis showed that the expression of F3H increased the regulation of flavonol synthase (FLS), dihydroflavonol 4-reductase (DFR), and slender rice mutant (SLR1) during BLB stress. The analysis of SA and JA signaling revealed an antagonistic interaction between both hormones and that F3H induction significantly promoted SA and inhibited JA accumulation in the transgenic lines. SA-dependent nonexpressor pathogenesis-related (NPR1) and Xa1 showed significant upregulation in the infected transgenic lines compared with the infected control and wildtype lines. Thus, the overexpression of F3H was essential for increasing BLB stress tolerance.  相似文献   
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134.
In this work, synthesis of Ni nanoparticles was carried out successfully by water extract of Allium jesdianum as a biochemical reducing agent in the presence of montmorillonite clay (MMT) as a natural solid support for the first time. Then the electrochemical activity of the synthesized nanocomposite was investigated in methanol electrocatalytic oxidation. MMT with high cation exchange capacity and nano layer structure was exposed to ion exchange conditions in nickel solution. Then Ni2+ ion exchanged form was used in this process as a source of ions and also capping agent. Water extract of Allium jesdianum used as a reducing agent due to abundant availability of phenolic and flavonoid contents. The synthesized Ni/MMT nanocomposite was characterized using UV–Vis spectroscopy (UV–Vis), Fourier Transform Infrared Spectroscopy (FT-IR), X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission electron microscopy (TEM) and Energy-dispersive X-ray spectroscopy (EDX). The surface of prepared modified electrode has been characterized using SEM to evaluate the morphology, showing uniform dispersion of Ni nanoparticles with mean diameter of 12 to 20 nm. The modified carbon paste electrode was then used in methanol electrocatalytic oxidation reaction. Methanol oxidation on the proposed modified electrode surface occurs at 0.6 V and 0.3 V in alkaline and acidic medium respectively. Also, the results showed the better performance of modified electrode toward methanol electrocatalytic oxidation in comparison with carbon paste electrode that is modified by ion exchanged MMT. Charge transfer coefficients and apparent charge transfer rate constant for the modified electrode in the absence of methanol in alkaline medium were respectively found as: αa = 0.53, αc = 0.37 and ks = 1.6 × 10−1 s−1. Also, the average value of catalytic rate constant for the electrocatalytic oxidation of methanol by the prepared nano-catalyst was estimated to be about 0.9 L·mol-1·s-1 by chronoamperometry technique. The prepared electrode was also effective for electrocatalytic oxidation of ethanol and formaldehyde in alkaline medium.  相似文献   
135.
In this paper, we demonstrated the successful fabrication of crosslinked porous films with varying monomer-crosslinker ratios, by photo-induced crosslinking during the breath figure formation. For all the samples fabricated, the pores at the peripheral regions appeared more uniform in size and showed higher degree of ordering, due to the interplay between the solvent evaporation and crosslinking reaction. The pore morphology remains similar despite varying film compositions, suggesting that the pore-fixing process is still dominated by the solvent evaporation similar to that of conventional breath figure process, and is less dependent on the crosslinking process. Detailed characterizations of the chemical and physical properties, including the glass transition temperature, thermal stability, and surface wettability of the porous films were carried out.  相似文献   
136.
The aim of this study was to investigate androgen receptor (AR) expression in the developing human urogenital tract. The distribution of AR was examined in paraffin-embedded tissue sections of the lower urogenital tract using 55 human embryos of 8-12 weeks of gestation. Immunohistochemistry was performed for AR detection and gender was determined by polymerized chain reaction. There were no differences in the distribution of AR in male and female embryos at any stage of gestation. AR was present only in the mesenchymal tissues of the urogenital sinus at 8 weeks whilst the epithelium was negative, but after 9 weeks the epithelium also showed progressively more positive staining. In the phallus, AR staining was prominent. There was far less staining in the epithelium of the urethral groove from 8 to 10 weeks, whilst the mesenchyme of the urethral folds showed positive staining. At 11 and 12 weeks, both the urethral groove and folds showed uniform staining. The genital tubercle, genital swelling and bulbourethral gland precusors were also positively stained, although paramesonephric ducts were negative. Staining was observed in the mesonephric duct from 9 weeks. There was an absence of staining in the rectum at all stages of gestation. The expression of AR in an epithelium may be dependent upon the mesenchyme. Mesenchymal-epithelial interactions played an important role in development, as has been described in experimental animals. AR expression could play a part in the growth of the genital organs.  相似文献   
137.
Neural Computing and Applications - Grid-connected photovoltaic (PV) systems play an important role in reducing emissions resulting from conventional fossil-fuel-based power plants. However, in...  相似文献   
138.
The optical diagnostic system of KSTAR consists of visible diagnostics including toroidal and poloidal Hα monitors, a visible survey spectrometer, and filterscopes. A re-entrant cassette made of stainless steel, containing five optical quartz windows has been developed to allow easy access of the visible diagnostics to the plasma. The configuration and manufacturing design of the diagnostic cassette and the installation of optical diagnostic systems within the cassette are described. The structural and thermal analysis of the diagnostic cassette and in situ calibration of optical diagnostics have also been performed. The optical lens system showed good image quality by spot diagram analysis.  相似文献   
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