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Heterogeneous foods are widely consumed but little is known about the dynamics of their breakdown during mastication. To investigate these dynamics the particle size and bolus mass at regular stages of the chewing sequence were investigated using a single subject, who was carefully selected according to strict mastication and dental criteria. A standardized volume of both a gelatine gel and chocolate matrix containing roasted peanuts was chewed and expectorated after a specified number of chews or at the point of swallowing. The mass of various components of the bolus was determined along with peanut particle parameters (d50, broadness (b), and specific surface area) at each interval.Results showed that for this subject the type of matrix influenced the pathway that the peanut particles (embedded inside each matrix) were broken down. The d50 of peanut particles within the bolus of the gelatine gel were greater than within the bolus of the chocolate throughout the chewing sequence until the point of swallowing. At the point of swallowing, the d50 of peanut particles inside the bolus of the gelatine gel and chocolate were the same. The broadness value (b) and specific surface area of the peanut particles in the bolus of the chocolate were greater than those in the bolus of the gelatine gel throughout the chewing sequence. The matrices also induced different dynamic trends in the mass of bolus components during the chewing sequence.  相似文献   
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The use of composite multiple feedback in a newly proposed virtual reality system enables the patient to perceive similar real-world performance in the virtual world. However, it might cause information overload, which makes the patient feel confused and distracted during training. The aim of this study is to investigate the effectiveness of having separate function-specific feedback pre-training prior to the final multiform feedback task. During the evaluating tests with thirty healthy subjects, it has been found that effective pre-training set could overcome the problem in the main task. Minor modifications on the pre-training set could overcome or aggravate the problem, which indicates the importance of choosing the correct pre-training parameters.  相似文献   
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Jim Nelson 《Cryptologia》2013,37(4):213-224
There are many requirements for commercial cryptosystems for transmission of intelligence between terminals, between terminals and computers, and between computers. Much commercial information has great value and can warrant the cost of cryptographic protection. This paper claims that the slow rate of implementation of commercial cryptosystems is due to the lack of standardization. This standardization is necessary to achieve general acceptance of cryptosystem products by users. General acceptance is required to permit production volumes which lead to reasonable crypto product prices. This paper discusses the standards efforts that are now ongoing, and projects the types of commercial cryptosystems which will be available in the near future.  相似文献   
107.
The transference and reactivity of proanthocyanidins is an important issue that affects the technological processing of some fruits, such as grapes and apples. These processes are affected by proanthocyanidins bound to cell wall polysaccharides, which are present in high concentrations during the processing of the fruits. Therefore, the effective extraction of proanthocyanidins from fruits to their juices or derived products will depend on the ability to manage these associations, and, in this respect, enzymes that degrade these polysaccharides could play an important role. The main objective of this work was to test the role of pure hydrolytic enzymes (polygalacturonase and cellulose) and a commercial enzyme containing these two activities on the extent of proanthocyanidin-cell wall interactions. The results showed that the modification promoted by enzymes reduced the amount of proanthocyanidins adsorbed to cell walls since they contributed to the degradation and release of the cell wall polysaccharides, which diffused into the model solution. Some of these released polysaccharides also presented some reactivity towards the proanthocyanidins present in a model solution.  相似文献   
108.

Despite the proven advantages of sampling-based motion planning algorithms, their inability to handle online navigation tasks and providing low-cost solutions make them less efficient in practice. In this paper, a novel sampling-based algorithm is proposed which is able to plan in an unknown environment and provides solutions with lower cost in terms of path length, runtime and stability of the results. First, a fuzzy controller is designed which incorporates the heuristic rules of Tabu search to enable the planner for solving online navigation tasks. Then, an adaptive neuro-fuzzy inference system (ANFIS) is proposed such that it constructs and optimizes the fuzzy controller based on a set of given input/output data. Furthermore, a heuristic dataset generator is implemented to provide enough data for the ANFIS using a randomized procedure. The performance of the proposed algorithm is evaluated through simulation in different motion planning queries. Finally, the proposed planner is compared to some of the similar motion planning algorithms to support the claim of superiority of its performance.

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The rumen is a complex microbial system of substantial importance in terms of greenhouse gas emissions and feed efficiency. This study proposes combining metagenomic and host genomic data for selective breeding of the cow hologenome toward reduced methane emissions. We analyzed nanopore long reads from the rumen metagenome of 437 Holstein cows from 14 commercial herds in 4 northern regions in Spain. After filtering, data were treated as compositional. The large complexity of the rumen microbiota was aggregated, through principal component analysis (PCA), into few principal components (PC) that were used as proxies of the core metagenome. The PCA allowed us to condense the huge and fuzzy taxonomical and functional information from the metagenome into a few PC. Bivariate animal models were applied using these PC and methane production as phenotypes. The variability condensed in these PC is controlled by the cow genome, with heritability estimates for the first PC of ~0.30 at all taxonomic levels, with a large probability (>83%) of the posterior distribution being >0.20 and with the 95% highest posterior density interval (95%HPD) not containing zero. Most genetic correlation estimates between PC1 and methane were large (≥0.70), with most of the posterior distribution (>82%) being >0.50 and with its 95%HPD not containing zero. Enteric methane production was positively associated with relative abundance of eukaryotes (protozoa and fungi) through the first component of the PCA at phylum, class, order, family, and genus. Nanopore long reads allowed the characterization of the core rumen metagenome using whole-metagenome sequencing, and the purposed aggregated variables could be used in animal breeding programs to reduce methane emissions in future generations.  相似文献   
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