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961.
Twin-screw extrusion texturization of extruded-expelled soybean flour   总被引:4,自引:0,他引:4  
Texturized soy proteins (TSP) have been produced from hexane-extracted soy flours having a narrow range of characteristics. The objective of this study was to determine the influence of protein dispersibility index (PDI) and residual oil content on extrusion texturization of partially defatted soy flours produced by extruding-expelling (E-E). Ten E-E processed soy flours having residual oil contents and PDI values of 5.5–12.7% and 35.3–69.1%, respectively, were texturized using a twin-screw extruder. Water-holding capacities were greater for TSP prepared from E-E processed soy flours with lower residual oil contents. Bulk densities were significantly lower for TSP prepared from E-E processed soy flours compared with a commercial product made from hexane-extracted soy flour. The texture characteristics of extended ground beef patties containing texturized E-E processed soy flour were similar to that of 19% fat ground beef. Flavor acceptability was directly correlated (R=0.761) with residual oil content of the E-E processed soy flours. However, lower residual oil and higher PDI flours exhibited better texturization and extrudate qualities.  相似文献   
962.
The authors documented syllable omission in one child's multisyllabic vocabulary from 10 to 20 months of age to evaluate L. Gerken's (1991, 1994, 1994) proposal that children organize their productions according to a trochaic metrical (strong–weak) template and omit syllables from target utterances that do not conform to this pattern. The trochaic template hypothesis was not supported by these early productions. Results indicated that the likelihood of producing a target syllable was influenced primarily by the strength of the prosodic stress placed on it and secondarily by its serial order within a word. Over time, the child demonstrated an increasing ability to include syllables with weaker prosodic stress in multisyllabic productions. Omissions became much less common with the onset of 2-word speech. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
963.
Vibrio parahaemolyticus is ubiquitous in estuarine environments and can be commonly found in seafood products. This bacterial pathogen continues to emerge as an important cause of foodborne illness, and several foodborne disease outbreaks caused by V. parahaemolyticus have been linked to the consumption of contaminated seafood, in particular those consumed raw such as oysters. In response to these outbreaks, especially during the 1990s, several cultural, immunological‐based and molecular detection methods have been developed, which allow for rapid detection and quantification of total and pathogenic V. parahaemolyticus. The development of molecular methodology has allowed for clinical and environmental isolates of V. parahaemolyticus to be subtyped, thus providing the framework for risk‐based strategies aimed at controlling foodborne outbreaks cause by this pathogen. It is important that the detection and typing methods strive to accomplish detection and differentiation of the pathogenic strains from environmental (non‐pathogenic) ones, as well as to detect the presence of the organism and not just the presence of V. parahaemolyticus produced toxins, which can also be produced by closely related species. This review covers the current status of detection and typing methodology for identification and characterisation of V. parahaemolyticus from seafood.  相似文献   
964.
Collective efficacy has received little research attention since its inception. Therefore, the objectives of this study were to develop a theory-based measure of collective efficacy and determine its relationship with another group phenomenon—group cohesion. Volleyball players (N?=?70) completed questionnaires designed to assess their perceptions of their teams' confidence in skills and abilities related to group tasks and processes. Several important outcomes emerged. First, a theory-based measure of collective efficacy was developed, and initial psychometric properties were established. Second, various aspects of collective efficacy were found to be positively correlated with group cohesion. Third, only certain aspects of a multidimensional collective efficacy measure were found to be predictive of task-related aspects of team cohesion. When considered together, the findings represent a promising step toward the investigation of collective efficacy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
965.
The genetically obese Zucker rat is a widely investigated model of pathological changes associated with type 2 diabetes. To assess cognitive function, obese and lean Zucker rats were tested on a variable-interval delayed alternation test of learning and memory. There were no group differences in learning the alternation rule or at short intervals, but obese rats were impaired at longer intervals where performance is hippocampus dependent. Plasma membrane association of the insulin sensitive glucose transporter, GLUT4, was reduced in the hippocampus of obese rats in the absence of changes in total GLUT4 and insulin receptor expression. These results parallel those of human studies in pointing to the susceptibility of the hippocampus and related structures to the adverse environment of diabetes mellitus. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
966.
Scrutiny into the composition of natural, or biological materials convincingly reveals that high material and structural efficiency can be attained, even with moderate-quality constituents, by hierarchical topologies, i.e., successively organized material levels or layers. The present study demonstrates that biologically inspired hierarchical designs can help improve the moderate properties of natural fiber polymer composites or biocomposites and allow them to compete with conventional materials for load-bearing applications. An overview of the mechanics concepts that allow hierarchical designs to achieve higher performance is presented, followed by observation and results from flexural tests on periodic and hierarchical cellular beams and plates made from industrial hemp fibers and unsaturated polyester resin biocomposites. The experimental data is shown to agree well with performance indices predicted by mechanics models. A procedure for the multi-scale integrated material/structural analysis of hierarchical cellular biocomposite components is presented and its advantages and limitations are discussed.  相似文献   
967.
The precision of point-of-gaze (POG) estimation during a fixation is an important factor in determining the usability of a noncontact eye-gaze tracking system for real-time applications. The objective of this paper is to define and measure POG fixation precision, propose methods for increasing the fixation precision, and examine the improvements when the methods are applied to two POG estimation approaches. To achieve these objectives, techniques for high-speed image processing that allow POG sampling rates of over 400 Hz are presented. With these high-speed POG sampling rates, the fixation precision can be improved by filtering while maintaining an acceptable real-time latency. The high-speed sampling and digital filtering techniques developed were applied to two POG estimation techniques, i.e., the high-speed pupil-corneal reflection (HS P-CR) vector method and a 3-D model-based method allowing free head motion. Evaluation on the subjects has shown that when operating at 407 frames per second (fps) with filtering, the fixation precision for the HS P-CR POG estimation method was improved by a factor of 5.8 to 0.035 degrees (1.6 screen pixels) compared to the unfiltered operation at 30 fps. For the 3-D POG estimation method, the fixation precision was improved by a factor of 11 to 0.050 degrees (2.3 screen pixels) compared to the unfiltered operation at 30 fps.  相似文献   
968.
We are interested in autonomous or unsupervised data mining. In the broad context of our work, we were interested in partitioning data in order to increase the information within each partition. An important aspect of this was data granulation. Clustering is an important aspect of data mining; it enables us to granulize the data. However, classic clustering methods require either the number of clusters and/or the approximate cluster centers. To avoid providing guidance, we used a variation of the Mountain Method to develop clustering parameters. This gave us satisfactory cluster centers. The estimated clusters' centers were then used in the data mining algorithm to develop and refine partitions. Experimental results of using the method on some data sets are reported. © 2005 Wiley Periodicals, Inc. Int J Int Syst 20: 415–432, 2005.  相似文献   
969.
The objectives of this study were to (1) compare a test for serum measurement of total Ca (tCa), Mg, and P (VetTest Chemistry Analyzer, IDEXX Laboratories Inc., Westbrook, ME) to reference methods (spectrophotometric assays on a Beckman Coulter 640e automated clinical chemistry analyzer; Beckman Coulter, Brea, CA), (2) determine the relationship between ionized Ca (iCa) and reference method tCa in the immediate postpartum period, and (3) assess the relative value of these blood Ca indices as predictors of neutrophil oxidative burst activity. Samples were collected from multiparous Holstein cows (n = 33) over the first 5 d in milk. A total of 183 samples for objective 1 and 181 samples for objective 2 were available. Neutrophil oxidative burst activity was assessed once between 2 and 5 d in milk (n = 29). Linear regression demonstrated strong relationships between serum tCa, Mg, and P concentrations measured by the VetTest compared with the reference method. Bland Altman analysis indicated that the VetTest values were higher than the reference method by 0.22 mmol/L for tCa, 0.12 mmol/L for Mg, and 0.16 mmol/L for P. Compared with hypocalcemia categorized at ≤2.0 or ≤2.125 mmol/L with the reference method tCa, thresholds for the VetTest measured tCa of ≤2.23 mmol/L (sensitivity = 87%, specificity = 89%) or ≤2.30 mmol/L (sensitivity = 86%, specificity = 96%) could be used. The relationship between whole-blood iCa and reference method serum tCa differed by sampling time point after calving. Compared with identification of hypocalcemia with serum tCa measurements from the reference method (thresholds of ≤2.0 and 2.125 mmol/L), a whole-blood iCa threshold of ≤1.17 mmol/L resulted in the highest combined sensitivities (94 and 82%) and specificities (80 and 94%) at either threshold. Ionized Ca measurements were more consistently related to outcomes of neutrophil oxidative burst activity measured in vitro. The VetTest measurements of serum tCa reliably identified hypocalcemia when thresholds were adjusted to account for the bias of the test. The variation in the relationship between iCa and reference method tCa in the days following parturition suggest that these measures cannot be used interchangeably as indicators of Ca status. The more consistent associations between iCa and in vitro measures of neutrophil function, compared with tCa, indicated that this may be a more sensitive predictor of functional outcomes associated with postpartum Ca status.  相似文献   
970.
A microtiter plate (MTP) method was developed to determine the quality of fats that are used in large‐scale processing using lipase catalysis. Two assay formats were followed: In the first approach, the fats were interesterified with p‐nitrophenol laurate using a lipase from Thermomyces lanuginosa; in the second approach, pH indicators were added to the fat samples containing lipase. A blind study using 29 fats showed that the MTP method using p‐nitrophenol as pH indicator allowed a rapid and reliable assignment of bad fats and an acceptable differentiation between fats of moderate and good quality.  相似文献   
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