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991.
We proposed an Intemet resource aggregation platform based on semantic web. The platform includes an Web Ontology Language(OWL) ontology design toolkit(VO-Editor) and a selective inference algorithm engine so that it can visually editing ontology and using novel selective reasoning for information aggregation. We introduce the VO-Editor and the principle of selective inference algorithm. At last a case of budget travel system is used to interpret the approach of Internet resources aggregation by this platform.  相似文献   
992.
Current uplink power control algorithm of code division multiple access (CDMA) time division duplex(TDD) system contains signal-to-interference-ratio(SIR) and interference measurement, which is based on history information. However, the adjustment of transmission power of one user equipment(UE) will affect SIR of the others, because the power control is done independently of the power adjustment of other UE's. So the convergence speed of power control is not fast and the system performance degrades. In the proposed algorithm, all UE's assigned in same time slot adjust their transmission power based on current information, which takes into account the adjustments of transmission power of all UE's. The simulation results indicated that the proposed algorithm outperforms the old algorithm.  相似文献   
993.
Pigmentary glaucoma is a significant cause of human blindness. Abnormally liberated iris pigment and cell debris enter the ocular drainage structures, leading to increased intraocular pressure (IOP) and glaucoma. DBA/2J (D2) mice develop a form of pigmentary glaucoma involving iris pigment dispersion (IPD) and iris stromal atrophy (ISA). Using high-resolution mapping techniques, sequencing and functional genetic tests, we show that IPD and ISA result from mutations in related genes encoding melanosomal proteins. IPD is caused by a premature stop codon mutation in the Gpnmb (GpnmbR150X) gene, as proved by the occurrence of IPD only in D2 mice that are homozygous with respect to GpnmbR150X; otherwise, similar D2 mice that are not homozygous for GpnmbR150X do not develop IPD. ISA is caused by the recessive Tyrp1b mutant allele and rescued by the transgenic introduction of wildtype Tyrp1. We hypothesize that IPD and ISA alter melanosomes, allowing toxic intermediates of pigment production to leak from melanosomes, causing iris disease and subsequent pigmentary glaucoma. This is supported by the rescue of IPD and ISA in D2 eyes with substantially decreased pigment production. These data indicate that pigment production and mutant melanosomal protein genes may contribute to human pigmentary glaucoma. The fact that hypopigmentation profoundly alleviates the D2 disease indicates that therapeutic strategies designed to decrease pigment production may be beneficial in human pigmentary glaucoma.  相似文献   
994.
An Erratum has been published for this article in Journal of Forecasting 23(6): 461 (2004) . This paper examines the problem of intrusion in computer systems that causes major breaches or allows unauthorized information manipulation. A new intrusion‐detection system using Bayesian multivariate regression is proposed to predict such unauthorized invasions before they occur and to take further action. We develop and use a multivariate dynamic linear model based on a unique approach leaving the unknown observational variance matrix distribution unspecified. The result is simultaneous forecasting free of the Wishart limitations that is proved faster and more reliable. Our proposed system uses software agent technology. The distributed software agent environment places an agent in each of the computer system workstations. The agent environment creates a user profile for each user. Every user has his or her profile monitored by the agent system and according to our statistical model prediction is possible. Implementation aspects are discussed using real data and an assessment of the model is provided. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
995.
996.
997.
Eolian loess is widely distributed on the various geomorphic surfaces between 700–2400 m a.s.l. on the northern slope of the Tian Shan. It is formed in a synchronous manner with dust transported from the Gurbantunggut Desert in the Junggar Basin. The thickest section of loess was found in the Shawan and Shihezi regions. Paleomagnetic and climatic proxy analyses of over 71 m of a loess-paleosol sequence on the highest terrace of the Qingshui He (River) in the Shawan show that the paleomagnetic Bruhues/Matuyama (B/M) boundary lies at the bottom of paleosol S8, at a depth of 69.5 m, and the bottom of the sequence was estimated to be ∼0.8 Ma. This implies that the extremely dry climatic conditions in the Junggar Basin and the initial Gurbantunggut Desert were present at least by 0.8 Ma. High-resolution grain size series demonstrate that this area and desert expansion experienced two dramatic periods of desert expansions that occurred at ∼0.65 Ma and 0.5 Ma, respectively; and the subsequent continuous enhancement led to the environment presently observed. This tremendous environmental effect, caused by large-scale expansion of the desert and arid region of inner Asia, might be an important driving force for the global temperature drop that occurred in the mid-Pleistocene.  相似文献   
998.
By comparing PGE patterns of sulfide ores with that of basic-ultrabasic dikes occurring in the Dajing Cu-polymetallic deposit, we discover that there are similar positive slopes between the basic-ultrabasic dikes and the black ores composed mainly of sphalerite and galena, reflecting affinity of their source. The PGE patterns of the yellow ores composed basically of chalcopyrite, arsenopyrite and pyrite are actually different. One is close to the pattern of the mantle lherzolite, and others resemble the pattern of the basic rocks. However, the concentrations of Ru are higher in the yellow ores, reflecting that sulfur attains or approaches saturation in their parent magma. The PGE characteristics of ores and dikes show that the magmas derived from the deep of crust and the metallogenic elements were supplied mainly by growth material of the crust. In addition, the mantle-derived magma also offered some elements.  相似文献   
999.
Superoxide activates mitochondrial uncoupling proteins.   总被引:64,自引:0,他引:64  
Uncoupling protein 1 (UCP1) diverts energy from ATP synthesis to thermogenesis in the mitochondria of brown adipose tissue by catalysing a regulated leak of protons across the inner membrane. The functions of its homologues, UCP2 and UCP3, in other tissues are debated. UCP2 and UCP3 are present at much lower abundance than UCP1, and the uncoupling with which they are associated is not significantly thermogenic. Mild uncoupling would, however, decrease the mitochondrial production of reactive oxygen species, which are important mediators of oxidative damage. Here we show that superoxide increases mitochondrial proton conductance through effects on UCP1, UCP2 and UCP3. Superoxide-induced uncoupling requires fatty acids and is inhibited by purine nucleotides. It correlates with the tissue expression of UCPs, appears in mitochondria from yeast expressing UCP1, and is absent in skeletal muscle mitochondria from UCP3 knockout mice. Our findings indicate that the interaction of superoxide with UCPs may be a mechanism for decreasing the concentrations of reactive oxygen species inside mitochondria.  相似文献   
1000.
A special extended basin topography is developed in the middle segment of the Altyn Tagh Fault Zone. The ratio of its length to width is over 50. The long boundaries at the two sides of the basin are controlled by the straight normal faults with strike-slip component. Within the basin, the Cenozoic strata are spread. The Altyn Tagh main fault goes through the basin, and a series of strike-slip topography was formed within the basin. The reverse thrust structures were formed at the two sides of the center of the basin, thus making the geological bodies composed of old metamorphic rocks at the two sides of the basin extrude vertically,and forming the extended massif (mountain) at the sides of the basin and parallel to the basin. This special topography was called the strike-slip fault basin. The giant extended strike-slip fault basin began to form during Pliocene, and its topography was basically formed during the late Pleistocene. It is the special topography formed during the strike-slip deformation process of the Altyn Tagh Fault Zone and under both transpression and uplifting.  相似文献   
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