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1.
The reduction in the molecular weight distribution during acid hydrolysis of ordinary and waxy maize starch occured in two stages: first amylopectin degraded to intermediate high molecular weight polysac-charides, secondly, these were further hydrolyzed. The amylose moiety of ordinary and high-amylose starch was not affected very much by the hydrolysis conditions used (0.1–1 M HCI, 40°C, 0.3–4 h), but the gelling properties of starch weakened. The amylopectin degradation products, probably branched dextrins, were shown to hinder the gel formation of amylose in the starch pastes.  相似文献   
2.
Identity and overall acceptance of two types of sour rye bread   总被引:1,自引:0,他引:1  
Response surface methodology was employed to study the influence of four recipe variables (wheat: rye flour ratio, bread acidity, ash content of rye flour and sodium chloride content) on the identity and overall acceptance of two rye bread types (soft and crisp rye bread). The subjects ( n = 79) rated attribute intensities, the extent to which the salient sensory properties and the overall sample corresponded to their expectations of rye bread, and the overall acceptance (pleasantness and purchase intentions). The acidity and ash content contributed the most to the extent to which a sample met subjects' expectations. The NaCl content was not critical. Consumer acceptance was affected by ash content, and by the interactions, NaCl content × acidity and wheat:rye ratio × ash content. The non-significance of NaCl content should encourage the baking industry to put low-salt rye products on the market.  相似文献   
3.
Neural networks and genetic algorithms for bankruptcy predictions   总被引:9,自引:0,他引:9  
We are focusing on three alternative techniques-linear discriminant analysis, logit analysis and genetic algorithms-that can be used to empirically select predictors for neural networks in failure prediction. The selected techniques all have different assumptions about the relationships between the independent variables. Linear discriminant analysis is based on linear combination of independent variables, logit analysis uses the logistical cumulative function and genetic algorithms is a global search procedure based on the mechanics of natural selection and natural genetics. In an empirical test all three selection methods chose different bankruptcy prediction variables. The best prediction results were achieved when using genetic algorithms.  相似文献   
4.
Genome-sequencing projects have revealed that Streptomyces bacteria have the genetic potential to produce considerably larger numbers of natural products than can be observed under standard laboratory conditions. Cryptic angucycline-type aromatic polyketide gene clusters are particularly abundant. Sequencing of two such clusters from Streptomyces sp. PGA64 and H021 revealed the presence of several open reading frames that could be involved in processing the basic angucyclic carbon skeleton. The pga gene cluster contains one putative FAD-dependant monooxygenase (pgaE) and a putatively bifunctional monooxygenase/short chain alcohol reductase (pgaM), whereas the cab cluster contains two similar monooxygenases (cabE and cabM) and an independent reductase (cabV). In this study we have reconstructed the biosynthetic pathways for aglycone synthesis by cloning and sequentially expressing the angucycline tailoring genes with genes required for the synthesis of the unmodified angucycline metabolite-UWM6-in Streptomyces lividans TK24. The expression studies unequivocally showed that, after the production of UWM6, the pathways proceed through the action of the similar monooxygenases PgaE and CabE, followed by reactions catalysed by PgaM and CabMV. Analysis of the metabolites produced revealed that addition of pgaE and cabE genes directs both pathways to a known shunt product, rabelomycin, whereas expression of all genes from a given pathway results in the production of the novel angucycline metabolites gaudimycin A and B. However, one of the end products is most probably further modified by endogenous S. lividans TK24 enzymes. These experiments demonstrate that genes that are either inactive or cryptic in their native host can be used as biosynthetic tools to generate new compounds.  相似文献   
5.
Recently the action systems formalism for parallel and distributed systems has been extended with the procedure mechanism. This gives us a very general framework for describing different communication paradigms for action systems, e.g. remote procedure calls. Action systems come with a design methodology based on the refinement calculus. Data refinement is a powerful technique for refining action systems. In this paper we will develop a theory and proof rules for the refinement of action systems that communicate via remote procedures based on the data refinement approach. The proof rules we develop are compositional so that modular refinement of action systems is supported. As an example we will especially study the atomicity refinement of actions. This is an important refinement strategy, as it potentially increases the degree of parallelism in an action system. Received February 1999 / Accepted in revised form July 2000  相似文献   
6.
The interaction between negative ions and 3 He superfluids was studied by using a time-of-flight spectrometer having a 10–3 relative resolution. The ions guided through a sample of rotating3He-A were found to be focused into the cores of the vortices present in this rotating superfluid. Two different types, with different core structures and presumably different numbers of circulation quanta associated with them, were found. The ion mobility along the vortex cores, c , observed in the absence of external magnetic field, can be explained by the mobility anisotropy of the A phase, which indicates that the vortices are continuous, i.e., consist of the A phase even in the core. In finite magnetic fields, a qualitatively similar continuous vortex structure was found, a result compatible with the earlier nuclear magnetic resonance (NMR) experiments, but also a new vortex type with an anomalously high c was seen when the vortex sample was prepared adiabatically. The observed strong ion focusing indicates broken w-symmetry in the core textures. This is in contradiction with the earlier numerical calculations on the optimal continuous vortex texture. Experiments to observe trapping of ions into the vortex cores were performed both in A and B phases. No trapping could be detected. Mobility measurements in stationary liquid were extended down toT=0.3T c . Comparison with the calculated transport coefficients yields A (T)=1.32 BCS (T) for the maximal A phase gap atP=29.3 bar, and B (T)=1.12 BCS (T) for the B phase gap at 4.8 bar. In the normal Fermi liquid a shallow minimum of ion mobility was detected aroundT2T c =5 mK.  相似文献   
7.
The technical enablers for mobile augmented reality (MAR) are becoming robust enough to allow the development of MAR services that are truly valuable for consumers. Such services would provide a novel interface to the ubiquitous digital information in the physical world, hence serving in great variety of contexts and everyday human activities. To ensure the acceptance and success of future MAR services, their development should be based on knowledge about potential end users’ expectations and requirements. We conducted 16 semi-structured interview sessions with 28 participants in shopping centres, which can be considered as a fruitful context for MAR services. We aimed to elicit new knowledge about (1) the characteristics of the expected user experience and (2) central user requirements related to MAR in such a context. From a pragmatic viewpoint, the participants expected MAR services to catalyse their sense of efficiency, empower them with novel context-sensitive and proactive functionalities and raise their awareness of the information related to their surroundings with an intuitive interface. Emotionally, MAR services were expected to offer stimulating and pleasant experiences, such as playfulness, inspiration, liveliness, collectivity and surprise. The user experience categories and user requirements that were identified can serve as targets for the design of user experience of future MAR services.  相似文献   
8.
Presentation of 11 cases of retroperitoneal sarcoma. Mean time from the beginning of symptoms to diagnosis is 6 months. The primary complementary study is CT. Surgery was performed in all cases, using complete resection in 6 cases, and partial resection in 5. Ten patients relapsed. 9 of which were treated with surgical rescue, in one or more occasions; chemotherapy was added in 6 cases and radiotherapy in 7. Survival at five years is 68%, with a mean follow-up of 66 months.  相似文献   
9.
The paper introduces ageing models of repairable components based on Bayesian approach. Models for the development of both failure rate and the probability of failure on demand are presented. The models are based on the assumption that the failure probability or rate has random changes at certain time points. This is modelled by assuming that the successive transformed failure probabilities (or rates) follow a Gaussian random walk. The model is compared with a constant increment model, in which the possible ageing trend is monotone. Monte-Carlo Markov Chain sampling is applied in the determination of the posterior distributions. Ageing indicators based on the model parameters are introduced, and the application of these models is illustrated with case studies.  相似文献   
10.
Cognition, Technology & Work - The work on the factory floor is gradually changing to resemble knowledge work due to highly automated manufacturing machines. In the increasingly automated work...  相似文献   
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