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1.
Molecular structure and granule morphology of native and heat‐moisture‐treated pinhão starch 下载免费PDF全文
Vania Z. Pinto Khalid Moomand Nathan L. Vanier Rosana Colussi Franciene A. Villanova Elessandra R. Zavareze Loong‐Tak Lim Alvaro R. G. Dias 《International Journal of Food Science & Technology》2015,50(2):282-289
Pinhão seed is an unconventional source of starch and the pines grow up in native forests of southern Latin America. In this study, pinhão starch was adjusted at 15, 20 and 25% moisture content and heated to 100, 110 and 120 °C for 1 h. A decrease in λ max (starch/iodine complex) was observed as a result of increase in temperature and moisture content of HMT. The ratio of crystalline to amorphous phase in pinhão starch was determined via Fourier transform infra red by taking 1045/1022 band ratio. A decrease in crystallinity occurred as a result of HMT. Polarised light microscopy indicated a loss of birefringence of starch granules under 120 °C at 25% moisture content. Granule size distribution was further confirmed via scanning electron microscopy which showed the HMT effects. These results increased the understanding on molecular and structural properties of HMT pinhão starch and broadened its food and nonfood industrial applications. 相似文献
2.
Robert Creutznacher Eric Schulze Georg Wallmann Prof. Dr. Thomas Peters Dr. Matthias Stein Dr. Alvaro Mallagaray 《Chembiochem : a European journal of chemical biology》2020,21(7):1007-1021
Bile acids have been reported as important cofactors promoting human and murine norovirus (NoV) infections in cell culture. The underlying mechanisms are not resolved. Through the use of chemical shift perturbation (CSP) NMR experiments, we identified a low-affinity bile acid binding site of a human GII.4 NoV strain. Long-timescale MD simulations reveal the formation of a ligand-accessible binding pocket of flexible shape, allowing the formation of stable viral coat protein–bile acid complexes in agreement with experimental CSP data. CSP NMR experiments also show that this mode of bile acid binding has a minor influence on the binding of histo-blood group antigens and vice versa. STD NMR experiments probing the binding of bile acids to virus-like particles of seven different strains suggest that low-affinity bile acid binding is a common feature of human NoV and should therefore be important for understanding the role of bile acids as cofactors in NoV infection. 相似文献
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Ramirez Juan R.; Crano William D.; Quist Ryan; Burgoon Michael; Alvaro Eusebio M.; Grandpre Joseph 《Canadian Metallurgical Quarterly》2004,18(1):3
The authors investigated relationships between marijuana and inhalant use and several cultural and demographic factors in Anglo American and Hispanic American adolescents (N=1,094). Outcome measures assessed lifetime and 30-day marijuana and inhalant use. Predictors and covariates used in logistic regression analyses were region, grade, gender, knowledge, acculturation, familism, and parental monitoring. Hispanic Americans exhibited higher usage across all measures. In this group, high acculturation was associated with low marijuana, but high inhalant, use. Across all participants, positive family relations and parental monitoring were strongly associated with attenuated marijuana use hut only among those most knowledgeable about drugs. Familism and monitoring were not associated with diminished usage among the less knowledgeable. For inhalants, monitoring combined with high knowledge or high familism was associated with diminished usage. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
5.
Alvaro E. Gil Author Vitae Author Vitae 《Automatica》2006,42(2):245-250
Resource allocation involves deciding how to divide a resource of limited availability among multiple demands in a way that optimizes current objectives. In this brief paper we focus on one type of distributed resource allocation problem where via an imperfect communication network multiple processors can share the load presented by multiple task types. We introduce asynchronous “cooperative” resource allocation strategies, and show that they lead to a bounded cumulative demand. 相似文献
6.
Compiler Verification has been identified as a vital process in the implementation of correct safety-critical systems. We extend here Hoare's refinement-algebra approach to compilation in order to include real-time languages in which processes interact asynchronously via communication queues. The existence of unique fixed-points is exploited to verify the implementation of crucial operators such as asynchronous input, delay and timeout. 相似文献
7.
Examined the relationship between aphasia type and lesion site in 80 subcortical stroke patients. Ss were classified as affected by aphasia, dysarthria, and nonaphasia, nondysarthria. Sites of lesions were identified by means of computerized tomography (CT) scan. No correlation between site of lesions and category group was found. Lesions of the same subcortical structures yielded different neurolinguistic impairment, whereas comparable linguistic patterns were observed with lesions of different deep areas. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
8.
This paper analyzes the welfare economics of three arrangements for purchasing health insurance: competitive markets in which consumers are free to choose among options with different levels of coverage and prices; systems with compulsory partial pooling which permit private firms to sell supplementary coverage; and government-run pools that purchase comprehensive coverage at a single price for all consumers. Competitive insurance markets are assumed to face the problem of 'adverse selection'. This refers to a situation in which the insurer cannot observe characteristics of individuals that affect the cost of insurance and that are known to the individuals. Competitive markets with adverse selection are not efficient because low risks cannot purchase comprehensive insurance coverage. However, government-run pools with comprehensive coverage are an inefficient solution to the problem of adverse selection. Compulsory partial coverage may represent an attractive alternative to both competitive markets and comprehensive pools. We discover two situations when government intervention of this type will succeed: when there are not many high risks in the population, and when the risk types are similar. We discuss the implications of these results for health insurance programs in several countries. Our results also have implications for the allocation of public funds for disease-prevention projects. A project targeted at high risks will produce external benefits for low risks, even though they are not directly affected by the program. However, a successful project might eliminate the market for private insurance; in this case the government should consider mandating partial insurance coverage. 相似文献
9.
G. Monrós J. Carda M. A. Tena P. Escribano J. Alarcón 《Journal of Materials Science》1992,27(2):351-357
The preparation of V-ZrSiO4 solid solutions starting from different ZrO2 precursors by using sol-gel methods is reported. The starting materials were hydrolysed and the dried gels were fired at a temperature between 500 and 900 °C with soaking times of 12h. The organic character of zirconia precursors was stronger, i.e. the starting material had more carbon atoms, a higher temperature was necessary to make the first crystalline phase appear (ZrO2(tetragonal)) and the temperature range for the whole phase transformation was narrower. In all dried gel samples the presence of infrared bands which might be associated with either Si-O-Zr or Si-O-V was not observed. On the other hand, some bands could be attributed to a silica network and ZrO8 groups. The main steps in V-ZrSiO4 solid solutions were confirmed. ZrO2(tetragonal) is crystallized on heating from an amorphous sample. The ZrO2(tetragonal) ZrO2(monoclinic) phase transformation then occurs and immediately afterwards the zircon formation begins. Finer textures in samples were obtained from polymeric gels rather than for colloidal gel samples, as seen from the scanning electron micrographs. 相似文献
10.
Manuel Alvar Andrea Torsello Alvaro Sanchez-Miralles José María Armingol 《Machine Vision and Applications》2014,25(5):1351-1368
Smart surveillance systems are increasingly being used to detect potentially dangerous situations. To do so, the common and easier way is to model normal human behaviors and consider as abnormal any new strange behavior in the scene. In this article, Dominant Sets is adapted to model most frequent behaviors and to detect any unknown event to trigger an alarm. It is proved that after an unsupervised training, Dominant Sets can robustly detect abnormal behaviors. The method is tested in several different cases and compared to other usual clusterization methods such as KNN, mixture of Gaussians or Fuzzy \(K\) -Means to confirm its robustness and performance. The overall performance of abnormal behavior detection based on Dominant Sets is better, being the error ratio at least \(1.5\) points lower than the others. 相似文献