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191.
A two-stage method for the reconstruction of missing data in the transmission of baseline JPEG coded images in error prone environments is proposed. In the first stage, we estimate the values of the missing DC coefficients. As effects of errors in estimating the missing DC values will appear as a number of stripes across the image, a technique for removing such stripes is also developed. In the second stage, the data of missing blocks is reconstructed by exploiting the correlation between adjacent blocks. Simulation results intricate that our reconstruction method performs very well. The two key contributions of our method are that it does not assume nondifferential encoding of the DC coefficients, and that it performs well in the reconstruction of diagonal edges.  相似文献   
192.
Although the Tactile Progressive Matrices (C. C. Rich, 1963), an adaptation of the Progressive Matrices for use with the blind, is cited in several reference sources, it is in fact defunct. The inclusion of this instrument may be the result of referencing based on secondary sources. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
193.
A series of three-dimensional numerical modeling experiments was conducted to determine the impacts of reaeration on the bioattenuation of petroleum hydrocarbon contaminants in groundwater systems. The influence of reaeration on plume length and mass loss was affected by four mechanisms including the groundwater mass transfer coefficient KL,GW, the concentration on partial pressure of O2 in the overlying soil gas PO2, the aquifer vertical dispersivity αv, and the reaeration zone Z or region of mixing between contaminated ground water and O2 supplied from the vadose zone. Results from this study showed that reaeration may reduce steady-state hydrocarbon plume length and mass by up to 87% as compared to the case in which reaeration is not considered. Among the four mechanisms, αv exerted the greatest influence on plume length followed by KL,GW, PO2, and Z. Comparisons between plume length and the ratio of reaeration transport KL,GW to hydraulic conductivity K indicated that appreciable reductions in steady-state plume length were possible when KL,GW/K ≥ 10?3.  相似文献   
194.
A maternal high fat diet (HFD) can have adverse effects on skeletal muscle development. Skeletal muscle PLIN proteins (PLIN2, 3 and 5) are thought to play critical roles in lipid metabolism, however effects of HFD on PLIN and lipases (HSL, ATGL, CGI‐58) in mothers as well as their offspring have yet to be investigated. The primary objective of this study was to determine whether maternal HFD would influence skeletal muscle lipase and PLIN protein content in offspring at weaning (19d) and young adulthood (3mo). Female rats (28d old, n = 9/group) were fed control (CON, AIN93G, 7 % soybean oil) or HFD (AIN93G, 20 % lard) for 10 weeks prior to mating and throughout pregnancy and lactation. All offspring were weaned to CON [n = 18/group, 1 female and 1 male pup per litter were studied at weaning (19d) and 3mo of age]. There was no effect of sex for the main outcomes measured in plantaris, therefore male and female data was combined. Maternal HFD resulted in higher triacylglycerol content in pups at 3mo (p < 0.05), as well as in the dams (p = 0.015). Maternal HFD resulted in higher PLIN5 content in pups at weaning and 3mo (p = 0.05). PLIN2 and PLIN5 content decreased at 3mo versus weaning (p < 0.001). HFD dams had a higher PLIN3 content (p = 0.016). Diet had no effect on ATGL, CGI‐58, or HSL content. In conclusion, exposure to a maternal HFD resulted in higher skeletal muscle lipid and PLIN5 content in plantaris of offspring through to young adulthood.  相似文献   
195.
A range of carbon nanoparticles, agglomerates and mineral phases have been identified in burning coal waste pile materials from the Douro Coalfield of Portugal, as a basis for identifying their potential environmental and human health impacts. The fragile nature and fine particle size of these materials required novel characterization methods, including energy-dispersive X-ray spectrometry (EDS), field-emission scanning electron microscope (FE-SEM), and high-resolution transmission electron microscopy (HR-TEM) techniques. The chemical composition and possible correlations with morphology of the nanominerals and associated ultra-fine particles have been evaluated in the context of human health exposure, as well as in relation to management of such components in coal-fire environments.  相似文献   
196.
One of the most annoying problems on the Internet is spam. To fight spam, many approaches have been proposed over the years. Most of these approaches involve scanning the entire contents of e-mail messages in an attempt to detect suspicious keywords and patterns. Although such approaches are relatively effective, they also show some disadvantages. Therefore an interesting question is whether it would be possible to effectively detect spam without analyzing the entire contents of e-mail messages. The contribution of this paper is to present an alternative spam detection approach, which relies solely on analyzing the origin (IP address) of e-mail messages, as well as possible links within the e-mail messages to websites (URIs). Compared to analyzing suspicious keywords and patterns, detection and analysis of URIs is relatively simple. The IP addresses and URIs are compared to various kinds of blacklists; a hit increases the probability of the message being spam. Although the idea of using blacklists is well known, the novel idea proposed within this paper is to introduce the concept of ‘bad neighborhoods’. To validate our approach, a prototype has been developed and tested on our university's mail server. The outcome was compared to SpamAssassin and mail server log files. The result of that comparison was that our prototype showed remarkably good detection capabilities (comparable to SpamAssassin), but puts only a small load on the mail server. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
197.
Molecular dynamics simulations were used to study deformation mechanisms during uniaxial tensile deformation of an amorphous polyethylene polymer. The stress-strain behavior comprised elastic, yield, strain softening and strain hardening regions that were qualitatively in agreement with previous simulations and experimental results. The chain lengths, number of chains, strain rate and temperature dependence of the stress-strain behavior was investigated. The energy contributions from the united atom potential were calculated as a function of strain to help elucidate the inherent deformation mechanisms within the elastic, yield, and strain hardening regions. The results of examining the partitioning of energy show that the elastic and yield regions were mainly dominated by interchain non-bonded interactions whereas strain hardening regions were mainly dominated by intra-chain dihedral motion of polyethylene. Additional results show how internal mechanisms associated with bond length, bond angle, dihedral distributions, change of free volume and chain entanglements evolve with increasing deformation.  相似文献   
198.
The interdisciplinary projects in bioinorganic and bioorganic chemistry of the Department of Chemistry, University of Basel led to the preparation of new systems that mimic biologically important processes and to the discovery of compounds from natural sources which are very promising with respect to medical applications. The advances in these areas are reported here.  相似文献   
199.
Reaction of [Ru(bpym)3]2+ (bpym = 2,2′-bipyridmidine) with hexacyanoruthenate under forcing conditions affords a mixture of the trinuclear species [(bpym)Ru{(µ-bpym)Ru(CN)4}2]2?, [1]2?, and the tetranuclear species [Ru{(µ-bpym)Ru(CN)4}3]4?, [2]4?, in which two or three (respectively) of the peripheral vacant bpym binding sites of [Ru(bpym)3]2+ are occupied by {Ru(CN)4}2? fragments. Thus, [1]2? and [2]4? have eight and twelve externally-directed cyanide groups respectively for use in forming high connectivity coordination networks. The crystal structure of HK[1]·2MeOH·6.5H2O reveals a one-dimensional ladder structure in which [1]2? anions are connected by (i) cyanide/K+ and (ii) bpym/K+ coordination interactions.  相似文献   
200.
A novel technique was developed to control the deposition of electrospun polyurethane fibers using a silicone collector substrate patterned with soft lithography. This method can be used to control selective fiber deposition with broad pattern dimensions (50–500 µm) over a large area. The combination of ease of use, low cost, tunability, and generation of relatively large fiber mats available with this technique is expected to advance our ability to mimic the orientation and anisotropic properties of native tissues to generate improved tissue engineering scaffolds.

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