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1.
As the number of fuzzy logic applications increases, demand for faster architectures will grow. Our design for a VLSI fuzzy processor uses fuzzy inference techniques that optimize processing time. Preprocessing that reduces the number of rules to be processed, parallel computation of active rule degrees of activation, and scalability are major features of this architecture. The journal issue contains a concise summary of this article. The complete article is linked to Micro's home page on the World Wide Web (http://www.computer.org/pubs/micro/micro.htm)  相似文献   
2.
The evolution of the main colloidal parameters in the seeded starved‐feed semi‐continuous emulsion polymerization of butyl methacrylate (BMA) was investigated, with the main purpose of assessing the effectiveness of the semi‐empirical relationship S = K · SS · ΔA/AS as a tool to define the surfactant/monomer feed ratio (∝ K) best suited to achieve a target particle size. In particular, the effect of the type and amount of surfactant [i.e., anionic, sodium dodecyl sulfate (SDS), or nonionic, Brij 58P] added during the semi‐continuous stage was considered. Coagulum formation was never observed under the adopted experimental conditions. To detect the occurrence of secondary nucleation or particle aggregation, or both, the particle size and number of particles, the surface tension and the particle surface coverage ratio were correlated. The best results were obtained with SDS and 0.8 ≤ K ≤ 3. In fact, under the selected experimental conditions, only with SDS did the number of particles remain nearly constant throughout the polymerization at the value defined by the seed latex; the particle size distribution was highly monodisperse, and the final particle diameter closely matched the calculated one (~ 120 nm). The above semi‐empirical relationship based on the adjustable parameter K was validated by running test polymerizations aimed at lattices with well‐defined particle size. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 3083–3094, 2006  相似文献   
3.
The size of the inner water cavity of reversed micelles formedin a triple system ‘water-surfactant-organic solvent’can be widely varied by changing the degree of surfactant hydration.This gives grounds to use reversed micelles as matrix microreactorsfor the design of supramolecular complexes of proteins. Usingultracentrifugation analysis, it has been demonstrated thatthe oligomeric composition of various enzymes (ketoglutaratedehydrogenase, alkaline phosphatase, lactic dehydrogenase, glyceraldehyde-3-phosphatedehydrogenase) solubilized in reversed micelles of Aerosol OT[sodium bis(2-ethylehexyl)sulfosuccinate] in octane changesupon variation of the degree of hydration. An oligomeric complexforms under conditions when the radius of the micelle innercavity is big enough to incorporate this complex as a whole.At lower degrees of hydration the micelles ‘uncouple’such complexes to their components. The catalytic propertiesof various oligomeric complexes have been studied. Possibilitiesof using reversed micelles for the separation of subunits ofoligomeric enzymes under non-denaturating conditions have beendemonstrated. In particular, the isolated subunits of alkalinephosphatase, lactic dehydrogenase and glyceralde-hyde-3-phosphatedehydrogenase have been found to be active in Aerosol OT reversedmicelles. The dependences of the catalytic activity of oligomericenzymes represent saw-like curves. The maxima of the catalyticactivity observed at these curves relate to the functioningof various oligomeric forms of an enzyme. The radii of the micelleinner cavity under conditions when these maxima are observedcorrelate with the linear dimensions of the enzyme oligomericforms. Correlation of the position of a maximum with the shapeof an oligomeric complex is discussed.  相似文献   
4.
Cytidine deaminase (CDA) is a cytosolic metalloprotein whose functional unit can be either a homotetramer (T-CDA) or a homodimer (D-CDA), depending on the species. In 1994, the first crystal structure of the dimeric Escherichia coli CDA has been published. However, a crystal structure of a tetrameric CDA was not determined until 2002. Prior to the disclosure of the experimentally elucidated structure of a tetrameric CDA, we derived a homology model of the human T-CDA employing the crystal structure of the dimeric E. coli CDA as a template. The comparison of our theoretical model with the crystal structure of the human T-CDA, subsequently published in 2004, validates our prediction: not only of the structural features of the monomer and the details of the binding site, but also the multimeric arrangement of the subunits were determined with high accuracy in our model. By means of a phylogenetic analysis conducted on CDAs from various organisms, we demonstrate that the E. coli CDA is one of the furthest known homologues of the human enzyme. Nonetheless, despite the evolutionary distance and, more importantly, the different multimeric arrangement of their functional units, the E. coli CDA proved to have all the necessary information to accurately infer the structure of its human homologue.  相似文献   
5.
Java has begun to open up new possibilities for accessing applications on the Web. With Java, developers can write applications as applets and insert them into Web pages. The user can then retrieve and execute them with local computing resources. We show how developers can use this feature to create a network computing platform that lets Web users share applications not specifically devised for network use, including those that are computationally intensive. With our approach, the network is not involved as long as the user executes operations on the graphical interface, which is executed locally on the client. Only when users require some computational response from the server do they need to access it. Access is straightforward; authorized users can access the application from any node connected with the Internet as long as they have a Java-enabled Web browser. We have used used one such network computing platform to port an existing tool and develop a new application  相似文献   
6.
Pathogenic/likely pathogenic variants in susceptibility genes that interrupt RNA splicing are a well-documented mechanism of hereditary cancer syndromes development. However, if RNA studies are not performed, most of the variants beyond the canonical GT-AG splice site are characterized as variants of uncertain significance (VUS). To decrease the VUS burden, we have bioinformatically evaluated all novel VUS detected in 732 consecutive patients tested in the routine genetic counseling process. Twelve VUS that were predicted to cause splicing defects were selected for mRNA analysis. Here, we report a functional characterization of 12 variants located beyond the first two intronic nucleotides using RNAseq in APC, ATM, FH, LZTR1, MSH6, PALB2, RAD51C, and TP53 genes. Based on the analysis of mRNA, we have successfully reclassified 50% of investigated variants. 25% of variants were downgraded to likely benign, whereas 25% were upgraded to likely pathogenic leading to improved clinical management of the patient and the family members.  相似文献   
7.
Objective

There is a pressing need to assess user-dependent reproducibility of multi-fibre probabilistic tractography in order to encourage clinical implementation of these advanced and relevant approaches. The goal of this study was to evaluate both intrinsic and inter-user reproducibility of corticospinal tract estimation.

Materials and methods

Six clinical datasets including motor functional and diffusion MRI were used. Three users performed an independent tractography analysis following identical instructions. Dice indices were calculated to quantify the reproducibility of seed region, fMRI-based end region, and streamline maps.

Results

The inter-user reproducibility ranged 41–93%, 29–94%, and 50–92%, for seed regions, end regions, and streamline maps, respectively. Differences in streamline maps correlated with differences in seed and end regions. Good inter-user agreement in seed and end regions, yielded inter-user reproducibility close to the intrinsic reproducibility (92–97%) and in most cases higher than 80%.

Discussion

Uncertainties related to user-dependent decisions and the probabilistic nature of the analysis should be considered when interpreting probabilistic tractography data. The standardization of the methods used to define seed and end regions is a necessary step to improve the accuracy and robustness of multi-fiber probabilistic tractography in a clinical setting. Clinical users should choose a feasible compromise between reproducibility and analysis duration.

  相似文献   
8.
The aim of this study was to estimate the hydrolytic degree and antioxidant activity of purified casein characterised by different haplotypes (αs1-, β- and k-casein) after in vitro digestion with two different enzymatic systems: pepsin from porcine gastric mucosa (EP) and a crude enzymatic extract from the edible mushroom Pleurotus eryngii. The used enzymes showed a different mode of casein catalysis with a consequent production of peptides of different antioxidant activity. The CN haplotype significantly influenced peptides production; in fact, the amino acid substitutions caused by genetic polymorphisms at the αs1-, β- and k-CN loci influenced the sites of enzymatic cleavage and therefore the produced peptides. The above is evidenced by the different antioxidant activity found in the hydrolysates depending on the used enzymatic system, the CN haplotype, and the CN haplotype × enzymatic treatment interaction. The findings of this study are a perspective for the production of specific foods that exert a biological effect in addition to the nutritional one.  相似文献   
9.
The presence of corticosteroid residues was assessed in urine and liver samples from livestock of Sicily. A total of 630 bovine samples were collected from farms and slaughterhouses. The samples were analysed using solid-phase extraction (SPE) coupled with ultra-performance liquid chromatography tandem mass spectrometry (UHPLC–MS/MS). All the corticosteroids found were under the maximum residue limit imposed by Commission Regulation (EC) 37/2010. About 4% of liver samples showed dexamethasone levels above the limit of detection (LOD), with a mean of 1.5 ± 0.2 µg kg?1. Betamethasone was found only in seven liver samples, with a mean of 1.6 ± 0.1 µg kg?1. Furthermore, prednisolone and prednisone were found only in urine and liver samples from slaughterhouse, probably related to the high rate of stress for bovines. These results suggest good control practices adopted by Sicilian farms, able to ensure the quality of food products.  相似文献   
10.
Wireless Networks - Fixtures play a significant role in ensuring the quality of products in manufacturing engineering. The paper considers fork-type parts that have a complex spatial configuration...  相似文献   
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