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31.
Soymilk was prepared from boiled and unboiled comminuted suspensions of dehulled soybean and water using pressurized homogenization (one pass and two pass). Particle size showed significant differences between soymilks homogenized by one pass and two pass. Apparent viscosities and total solid contents showed significant differences between boiled and unboiled treatments. Soymilks exhibited pseudoplastic and thixotropic behavior and Arrhenius model was fitted to express temperature dependence of apparent viscosity. Microscopic images showed hydrated, separated, uniformly distributed, and homogeneous particles in boiled two-pass soymilk as they were disrupted easily and it was selected as the best treatment for processing soymilk containing all of the soybean solids.  相似文献   
32.
The Particle Swarm Optimization (PSO) method was employed to optimize an industrial chemical process characterized by being difficult to be optimized by conventional deterministic methods. The chemical process is a three phase catalytic slurry reactor (tubular geometry) in which the reaction of the hydrogenation of o-cresol producing 2-methyl-cyclohexanol is carried out. The optimization problem was formulated considering as input variables the operating conditions of the reactor and as objective function the maximization of productivity, subject to the environmental constraint of conversion. The process was represented by a multivariable non-linear rigorous mathematical model and in order to solve the optimization problem, the performance of the PSO algorithm was evaluated considering four sets of parameters values suggested by the literature. PSO demonstrated to be efficient and robust to solve the constrained optimization problem, independently of the values of the PSO parameters. The solution of the rigorous mathematical model of the reactor was associated with a high computational burden, and although the PSO algorithm presented high rate of convergence, the attempt to make possible the optimization in a timeframe suitable to real time applications failed because the algorithm lost robustness (fraction of the number of runs the algorithm reached the optimization goal) when run with a reduced number of function evaluations. Therefore, if this type of application is desired, simplified mathematical models with fast and simple numerical methods must be preferred.  相似文献   
33.
Advertising activities are one of the main aspects of companies. Its global evaluation is an important index, not only within economic sectors, but also for public economic policies. The evaluation of the adverts is carried out by specialised companies, which deliver advertisement expenditure information. Their work consist in an exhaustive collection of adverts (e.g., all adverts from any media), and deliver information (integrated from every media) relevant for their clients. The delivered information can range from statistical data to bear witness of an advertisement campaign. Important quality indicators for the delivered information are the exhaustiveness, the delay of delivering and a correct identification of different versions of an advert. In this article, we present an advanced computer-aided system for collecting and delivering advertising information from magazines and daily press. The system provides computer-aided data validation and exploitation resources. Using computerised document image analysis and image database indexing and retrieval, the system is able to locate an advert in a page, extract relevant quality indicators and search the advert (or similar ones) in a database. This tool is configured as an intranet and offers resources for image data acquisition, storage/retrieval and advert quality indicators extraction, however, the key of the system is the underlying idea of incorporating computer-aided visual information management.The EU has funded the system construction within the program: European Take-up of essential Information Society Technologies, Integrated Machine Vision (EUTIST-IMV), task CV-AdControl. .  相似文献   
34.
In this paper, a MAS for system identification and process control is presented. In particular, this MAS implements a self‐tuning regulator (STR) scheme. It has adopted FIPA specifications because they have become a stronger standard in MAS development and they involve not only agent language specifications but also agent management and conversations. In this work, an Ontology Agent (OA) is included, using DAML + OIL as ontology language. The obtained results validate this approach in the implementation of well‐known algorithms for control process.  相似文献   
35.
We compared the biological activity of a new group of keto-C-glycosides to that of a narrow spectrum of unsaturated ketonucleosides in a panel of non-small-cell lung cancer (NSCLC) cells with various levels of intrinsic resistance to standard chemotherapy drugs. Unlike cisplatin, etoposide, adriamycin, or taxol, for which a significant difference in the cytotoxic effect was observed between sensitive cell lines (H460, H125, and MGH4) and drug-resistant cell lines (H661, MGH7, and FADU), nucleoside analogs were equally cytotoxic in NSCLC cell lines, with compound 92 being 10-fold more active than compound 43, 44, 81, or 161, while compound 3 was the least active. Apoptotic measurements with flow cytometric analysis of terminal uridine deoxynucleotide nick end-labeled cells revealed that the cytotoxic activity of these nucleosides correlated with their potency to induce apoptosis. Compound 92 triggered death in cells with wild-type p53, mutated p53, or p53 gene deletion. Our findings suggest that keto-C-glycosides may be promising alternative anticancer agents which merit further studies in in vivo cancer models refractory to standard chemotherapy drugs.  相似文献   
36.
BACKGROUND: A low-flow situation in arterial and venous grafts has been associated with high rates of perioperative infarction and mortality. This study was designed to look at intraoperative graft flow and resistance in patients with coronary artery disease. METHODS: Coronary artery bypass graft flow was measured in 46 patients. Transit-time flow was used for coronary flow measurements at rest as well as after maximal vasodilation with adenosine infusion. RESULTS: Forty-three of the 46 patients showed normal internal mammary artery graft flow (>20 mL/min); 3 patients had no or minimal graft flow. Redoing the graft anastomosis in these 3 patients resulted in normalization of graft flow. The mean flow increased significantly after correction from 0.5 +/- 0.7 mL/min to 15.7 +/- 9.6 mL/min (p < 0.02). Conversely, vascular resistance decreased significantly from 138 +/- 10 to 4.8 +/- 1.8 Ohmv (p < 0.0001), as did the pulsatility index (from 146.9 +/- 95.7 to 3.4 +/- 1.8; p < 0.001). After correction, coronary flow reserve was 2.5 +/- 1.1. CONCLUSIONS: Measurements of intraoperative flow and resistance as well as derived variables allow assessment of early graft function and thus help prevent graft failure and reduce perioperative infarction. Transit-time volume flow might be a simple tool for quality control in coronary bypass procedures.  相似文献   
37.
INTRODUCTION: Moebius's syndrome is an entity present at birth, characterized by oculofacial paralysis and external ophthalmoplegia. Other cranial nerves can also be affected and associated to skeletal abnormalities and neurologic symptoms. It appears sporadically, sometimes of familiar nature, presenting special facies with total absence of facial expression and severe strabismus. The pathogenesis of the syndrome still remains unknown, being the transitory situation of fetal hypoxia/ischemic the most accepted theory. In some cases chromosomal abnormalities have been detected. CLINICAL CASE: We reported three children with different symptoms, two of them are siblings whose father is affected, but he was not diagnosed until adult age. CONCLUSIONS: We conclude pointing out the different presentation of the disease, the appearance in several members of a family and its chronically evolution.  相似文献   
38.
The authors propose a comprehensive approach to laboratory diagnosis of seasonal transmissible infections, based on modern methods permitting etiological deciphering of disease. A universal diagnostic algorithm notably accelerated the laboratory diagnosis due to cutting the period between collection of material from a patient and consecutive screening for antibodies to agents of tick-borne encephalitis, Lyme disease, and California encephalitis.  相似文献   
39.
The Escherichia coli Fpg protein is involved in the repair of oxidized residues. We examined, by targeted mutagenesis, the effect of the conserved lysine residue at position 57 upon the various catalytic activities of the Fpg protein. Mutant Fpg protein with Lys-57-->Gly (K57G) had dramatically reduced DNA glycosylase activity for the excision of 7,8-dihydro-8-oxo-guanine (8-oxoG). While wild type Fpg protein cleaved 8-oxoG/C DNA with a specificity constant ( k cat/ K M) of 0.11/(nM@min), K57G cleaved the same DNA 55-fold less efficiently. FpgK57G was poorly effective in the formation of Schiff base complex with 8-oxoG/C DNA. The efficiency in the binding of 8-oxoG/C DNA duplex for K57G mutant was decreased 16-fold. The substitution of Lys-57 for another basic amino acid Arg (K57R) had a slight effect on the 8-oxoG-DNA glycosylase activity and Schiff base formation. The DNA glycosylase activities of FpgK57G and FpgK57R using 2,6-diamino-4-hydroxy-5N-methylformamidopyrimidine residues as substrate were comparable to that of wild type Fpg. In vivo, the mutant K57G, in contrast to the mutant K57R and wild type Fpg, only partially restored the ability to prevent spontaneously induced transitions G/C-->T/A in E.coli BH990 ( fpg mutY ) cells. These results suggest an important role for Lys-57 in the 8-oxoG-DNA glycosylase activity of the Fpg protein in vitro and in vivo.  相似文献   
40.
We systematically examined relations among 6 measures of child language derived from 3 sources, including observations of the child's speech with mother, experimenter assessments, and maternal reports. A total of 184 20-month-olds and their mothers contributed complete information about child language comprehension and expression. Correlations of child language measures with socioeconomic status and maternal education were accounted for, as were correlations of child language measures with mothers' verbal intelligence, maternal report measures with mothers' tendency to respond in a socially desirable fashion, and experimenter assessments with child social competence. Structural equation modeling supported (1) strong relations among child language measures derived from observations of the child's speech with mother, experimenter assessments, and maternal reports; (2) the loading of multiple measures of child language from different sources on a single latent construct of vocabulary competence; and (3) the predictive validity of the vocabulary competence latent variable at 20 months, as well as receptive vocabulary specifically, for both verbal and performance IQ (verbal better than performance) at 48 months. Neither an index of child monologing (a nonvocabulary language measure) nor symbolic play (a nonlinguistic representational measure) covaried with vocabulary competence. Girls consistently outperformed boys on individual language measures, but no differences emerged in any model in the fit for boys and girls.  相似文献   
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