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91.
The development of new production lines of extruded ready-to-eat (RTE) snacks often results in high losses of edible food due to the trial-and-error approach in industry. Being able to predict extrudate characteristics of new formulations before having to run trials on industrial scale would be beneficial for reducing waste and having a more efficient development process. With this study, the correlation between pasting properties of seven blends of flours/starches and extrudate characteristics was investigated (100% corn grits, 25% and 50% replacement of corn grits with high amylose starch, potato starch, and rice flour). The predictive power of pasting characteristics on extrudate's moisture content, water absorption and solubility index, sectional expansion index (SEI) and hardness was studied. Results indicated the potential of predicting SEI, water solubility index (WSI), and water absorption index (WAI) of RTE-snacks. WSI and WAI were, respectively, negatively correlated with peak temperature (R2 = 0.897), and positively with peak temperature and positively with trough viscosity (R2 = 0.855). One can conclude that the rheometer can be a useful tool to gain insight into the characteristics of the extrudate, although further research with enlargement of the dataset is necessary to make the rheometer effectively deployable for potentially other extrudate characteristics.  相似文献   
92.
INTRODUCTION: A population-based cross-sectional study was conducted in Pelotas, Southern Brazil, with the objective of determining the prevalence of obesity and identify associated, variables as this condition increased markedly in the country between 1974 and 1989. MATERIAL AND METHODS: One thousand and thirty-five adults between 20 and 69 years of age were studied. Obesity was defined as a Body Mass Index--BMI--equal to or over 30 Kg/square meter). The multivariate analyses took into account the hierarchical model of the variables associated with obesity for both men and women. RESULTS: The prevalence for the overall population was of 21% (CI 18-23). It was higher among women--25% (CI 22-29) than for men--15% (CI 12-18). Socioeconomic status was positively associated with obesity among men, whereas the opposite situation was reported for women, with those belonging to the poorest social strata presenting increased BMI. Reported obesity in their parents was associated with increased BMI in the subjects, and this association remained statistically significant even after compensating for the effect of possible confounding variables. Self-reported diabetes and arterial hypertension doubled the risk of obesity, whereas non-smoking was associated with obesity only among women. Variables which were not associated with obesity after adjusting for confounders were alcohol consumption, marital status and parity. Women having more daily meals were less prone to obesity, even after controlling for confounders, and this association was not quite significant for men (p = 0.07). CONCLUSIONS: The prevalence of obesity was higher among women, and important differences in risk factors were noticed when the population was considered by sex.  相似文献   
93.
Integrating diverse energy sources to produce cost‐competitive fuels requires efficient resource management. An optimization framework is proposed for a nationwide energy supply chain network using hybrid coal, biomass, and natural gas to liquids (CBGTL) facilities, which are individually optimized with simultaneous heat, power, and water integration using 162 distinct combinations of feedstock types, capacities, and carbon conversion levels. The model integrates the upstream and downstream operations of the facilities, incorporating the delivery of feedstocks, fuel products, electricity supply, water, and CO2 sequestration, with their geographical distributions. Quantitative economic trade‐offs are established between supply chain configurations that (a) replace petroleum‐based fuels by 100%, 75%, and 50% and (b) utilize the current energy infrastructures. Results suggest that cost‐competitive fuels for the US transportation sector can be produced using domestically available coal, natural gas, and sustainably harvested biomass via an optimal network of CBGTL plants with significant GHG emissions reduction from petroleum‐based processes. © 2012 American Institute of Chemical Engineers AIChE J, 2012  相似文献   
94.
Endowing mesh routers with multiple radios is a recent solution to improve the performance of wireless mesh networks. The consequent problem to assign channels to radios has been recently investigated and its relation to the routing problem has been revealed. The joint channel assignment and routing problem has been shown to be NP-complete and hence mainly heuristics have been proposed. However, such heuristics consider wireless links just like wired links, whereas disregarding their peculiar features. In this paper, we consider the impact of tuning the transmission power and rate of the wireless links on the efficiency of the channel assignment. Then, we present a channel, power and rate assignment heuristic and compare its performance to previously proposed algorithms.  相似文献   
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96.
ABSTRACT:  This study evaluated the effect of pH on the microstructure of cream cheese and compared pH-induced changes in its microstructure with concomitant changes in cheese firmness and meltability. On 4 different days, experimental batches of cultured hot pack cream cheese were manufactured and analyzed for initial chemical composition. The cheeses were then sectioned into samples that were randomly assigned to 7 different treatment groups. Three groups were exposed to ammonia vapor for 1, 3, and 5 min to increase the pH; 3 groups were exposed to acetic acid vapor for 30, 60, and 90 min to decrease the pH; and 1 unexposed group served as the control. After equilibration at 4 °C, samples were analyzed for pH, firmness, meltability, and microstructure by scanning electron microscopy. The effects of experimental treatments on cheese pH, firmness, and meltability were analyzed by randomized complete block analysis of variance (ANOVA). Relationships between cheese pH and firmness and meltability were evaluated by regression. Experimental treatments significantly affected cheese pH, firmness, and meltability. Cheese firmness decreased and meltability increased with increasing pH from about pH 4.2 to 6.8. Cheese microstructure also changed dramatically over the same approximate pH range. Specifically, the volume of the protein network surrounding the fat droplets increased markedly with increasing pH, presumably due to casein swelling. These data support the hypothesis that protein-to-water interactions increased as the cheese pH increased, which gave rise to progressive swelling of the casein network, softer texture, and increased meltability.  相似文献   
97.
98.
The incremental frequency amplitude and phase tracker (IFAPT) is a recursive algorithm that estimates the parameters of piecewise-linear approximation to assumed continuous narrow-band signals. The parameters are amplitude, phase, and their respective slopes. The simple, recursive nature of IFAPT enables its direct interaction with recursive algorithms, such as the Viterbi and the BCJR in the APP SISO module, used for iteratively decoding concatenated codes. An augmented APP (A 2P2)-module, containing IFAPT and BCJR algorithms, is here applied to iterative decoding serial concatenated convolutional codes under Rayleigh fading conditions with diversity reception. The bit-error rate under Rayleigh fading with dual diversity reception at E bT/N0=6 dB and fdTs=10-2 is 10-4, where E bT is the total mean energy per bit in both diversity branches, fd is the Doppler frequency, and Ts the symbol time  相似文献   
99.
An [M, n] spherical signal set is a collection ofM unit-norm vectors in the Euclideann-dimensional space n . Itsconfiguration matrix C is the matrix of the scalar products between pairs of vectors. isgeometrically uniform if, given any two vectors x i , x j there exists an isometry that transforms x i to x j while leaving invariant. Agenerating group of is a group of isometries of n that transform any given vector of into each of the vectors in while leaving invariant. In this paper we characterize the configuration matrix of a geometrically uniform spherical signal set and we show how its generating groups can be obtained.Parts of an earlier version of this paper were presented at the IEEE International Symposium on Information Theory, Ithaca, NY, 1977  相似文献   
100.
Bartter (BS) and Gitelman (GS) syndrome are autosomal recessive inherited tubulopathies, whose clinical diagnosis can be challenging, due to rarity and phenotypic overlap. Genotype–phenotype correlations have important implications in defining kidney and global outcomes. The aim of our study was to assess the diagnostic rate of whole-exome sequencing (WES) coupled with a bioinformatic analysis of copy number variations in a population of 63 patients with BS and GS from a single institution, and to explore genotype-phenotype correlations. We obtained a diagnostic yield of 86% (54/63 patients), allowing disease reclassification in about 14% of patients. Although some clinical and laboratory features were more commonly reported in patients with BS or GS, a significant overlap does exist, and age at onset, preterm birth, gestational age and nephro-calcinosis are frequently misleading. Finally, chronic kidney disease (CKD) occurs in about 30% of patients with BS or GS, suggesting that the long-term prognosis can be unfavorable. In our cohort the features associated with CKD were lower gestational age at birth and a molecular diagnosis of BS, especially BS type 1. The results of our study demonstrate that WES is useful in dealing with the phenotypic heterogeneity of these disorders, improving differential diagnosis and genotype-phenotype correlation.  相似文献   
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