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101.
Although a loss-of-function mutation has been identified in familial Parkinson’s disease PARK7, the wild-type of DJ-1 is known to act as an oxidative stress sensor in neuronal cells. Recently, we identified UCP0045037 as a compound that bound to the reduced form of DJ-1 by in silico virtual screening. In this study, we determined the neuroprotective effects of UCP0045037 against focal cerebral ischemia-induced neurodegeneration in rats. Hydrogen peroxide-induced cell death was significantly inhibited by UCP0045037 in both rat mesencephalic dopaminergic neurons and human normal SH-SY5Y cells. In contrast, DJ-1-knockdown SH-SY5Y cells lost the protective activity of UCP0045037. These results suggest that UCP0045037 interacts with endogenous DJ-1 and produces a neuroprotective response.  相似文献   
102.
103.
The pressure sensitive adhesive (PSA) properties of two samples of poly(vinyl ethylene-co-1,4-butadiene) (V-BR) (vinyl content: 47.4 and 60 wt%) blended with hydrogenated terpene resin (CLEARON P125) were measured on blend compositions having CLEARON P125 contents (by weight) of 10%, 30% and 50%. The maximum values of 180° peel adhesion, rolling ball tack and probe tack were observed with a V-BR/CLEARON P125 70/30 blend, whereas the maximum values of holding power were obtained with a 50/50 V-BR/CLEARON P125 blend. In these blends, the miscibility between V-BR and CLEARON P125 was confirmed by means of SEM, DSC and light scattering. The influences of surface tension and dynamic mechanical properties on PSA properties were investigated. The surface tension values were essentially the same in all the V-BR/CLEARON P125 blends. Minimum values of storage modulus G′ and loss modulus G″ at room temperature in V-BR/CLEARON P125 blends were obtained with a 70/30 blend. Thus, it is believed that in V-BR/CLEARON P125 blends, 180° peel adhesion and tack are related to the dynamic mechanical properties.  相似文献   
104.
We propose and demonstrate a CWDM full-mesh wavelength-routing system with an asymmetric physical star topology. We design a wavelength router to optimize this topology in which the node distances from the wavelength router are unequal. In addition, the router utilizes all the wavelengths making it possible to increase the maximum number of nodes in the system. The routing function is confirmed experimentally using transceivers with two different optical budgets  相似文献   
105.
The rationalization of various aspects of the mechanism of chirality induction in supramolecular assemblies based upon the complexes formed between an ethane-linked bisoctaethylporphyrin and chiral ligands is described. The influence of various controlling factors such as bonding strength, host-guest steric interactions, equilibria and thermodynamic parameters, temperature and solvent effects, role of the center metal ion, stoichiometry, and phase transition on the chirality induction processes have been investigated, and the results and implications are discussed. As a result of such detailed understanding, it is possible to employ this bisporphyrin system as an effective chirality sensor for the determination of absolute configuration.  相似文献   
106.
The group refractive index of air in laboratory conditions is measured directly between adjacent femtosecond laser pulses by a new interferometry technique. Measurement of the repetition rate of the mode-locked pulse train that gives the maximum amplitude of the interference-signal envelope enables us to determine the group refractive index of air within a standard deviation of 2 x 10(-7). This simple method without vacuum reference is attractive for measuring the group refractive index needed for precise distance measurements in open fields.  相似文献   
107.
108.
The joint torque which sets human limbs into motion is generated by a separate group of muscles provided for each joint. As the activation of each muscle is determined by a neural input, a neuromuscular system controlling all muscles has to be considered in order to understand human movements. In this study, an optimal control model of a neuromuscular system is investigated, and its control characteristics are examined. First, the dynamic and mechanical properties of a muscle are examined, and a neuromuscular system is formulated mathematically. Second, a performance criterion for the optimal control model is defined in order to characterize the dynamic behavior of the neuromuscular system, and a mathematical procedure for producing optimal trajectories is represented. Third, optimal trajectories in human arm movements are produced under various conditions of movement, and these trajectories are compared with experimentally observed ones. It is then verified that the optimal trajectories demonstrate human arm movements well. Finally, the behavior of individual muscles in various movements is examined quantitatively by means of simulation results, and the control characteristics of the human neuromuscular system are investigated. This work was presented in part at the Sixth International Symposium on Artificial Life and Robotics, Tokyo, January 15–17, 2001.  相似文献   
109.
The stable marriage problem (SMP) seeks matchings between n women and n men which would result in stability, and not lead to divorce or extramarital affairs. We have introduced a network consisting of nodes which represent matchings, and links between nodes which attain stability by exchanging a partner between two pairs. The network is depicted with nodes laid out to involve several coordinates which indicate either women’s satisfaction or men’s or both. With the network visualization, regularity and symmetry can be made conspicuous in specific instances of the SMP such as the Latin SMP.  相似文献   
110.
The technological advancements in digital imaging, the widespread popularity of digital cameras, and the increasing demand by owners and contractors for detailed and complete site photograph logs have triggered an ever-increasing growth in the rate of construction image data collection, with thousands of images being stored for each project. However, the sheer volume of images and the difficulties in accurately and manually indexing them have generated a pressing need for methods that can index and retrieve images with minimal or no user intervention. This paper reports recent developments from research efforts in the indexing and retrieval of construction site images in architecture, engineering, construction, and facilities management image database systems. The limitations and benefits of the existing methodologies will be presented, as well as an explanation of the reasons for the development of a novel image retrieval approach that not only can recognize construction materials within the image content in order to index images, but also can be compatible with existing retrieval methods, enabling enhanced results.  相似文献   
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