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1.
The prediction of six different sensory texture attributes of twenty-seven potato samples based on uniaxial compression curve features and full uniaxial compressions curves is reported. The data set comprised five varieties, sorted in dry matter bins, and sampled at two storage times. The predictions of most of the sensory texture attributes from full compression curves performed better than just using curve features. Furthermore, force-deformation curves are shown to give slightly better predictions than stress-strain curves. For most of the texture attributes better predictions were obtained using uniaxial compression data from raw potato samples as compared to cooked samples. This study is meant to open up a debate on interpreting the information in uniaxial compression curves in relation to sensory texture quality. Multivariate analysis can handle this and can further give insight about where in the curve the information relevant for the predictions of the sensory attributes is found.  相似文献   
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Distinguishable patterns of mass homeownership have emerged across industrialised societies in recent decades, and have become increasingly central in comparative analyses of housing systems. This paper examines the nature of differences and similarities within and between two particular groups of societies where owner occupation dominates housing demand and policy systems, one constituted of English-speaking, Anglo-Saxon societies, and another of East Asian societies. The paper considers the potential of forming loose models based on core divergences in terms of systems, regimes and socio-ideological relationships. The aim is to further illustrate interactions between housing systems and welfare regimes in international contexts. Comparisons of housing and welfare elements are broadly related between societies, rather than quantitatively isolated, as systems are substantially variegated across the East Asian region. However, a loose system-model provides considerable insight into convergence within the group in regards to how housing systems have served a minimal social-welfare regime type.  相似文献   
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We introduce a new probabilistic approach to dealing with uncertainty, based on the observation that probability theory does not require that every event be assigned a probability. For a nonmeasurable event (one to which we do not assign a probability), we can talk about only the inner measure and outer measure of the event. In addition to removing the requirement that every event be assigned a probability, our approach circumvents other criticisms of probability-based approaches to uncertainty. For example, the measure of belief in an event turns out to be represented by an interval (defined by the inner and outer measures), rather than by a single number. Further, this approach allows us to assign a belief (inner measure) to an event E without committing to a belief about its negation -E (since the inner measure of an event plus the inner measure of its negation is not necessarily one). Interestingly enough, inner measures induced by probability measures turn out to correspond in a precise sense to Dempster-Shafer belief functions. Hence, in addition to providing promising new conceptual tools for dealing with uncertainty, our approach shows that a key part of the important Dempster-Shafer theory of evidence is firmly rooted in classical probability theory. Cet article présente une nouvelle approche probabiliste en ce qui concerne le traitement de l'incertitude; celle-ci est basée sur l'observation que la théorie des probabilityés n'exige pas qu'une probabilityé soit assignée à chaque événement. Dans le cas d'un événement non mesurable (un événement pour lequel on n'assigne aucune probabilityé), nous ne pouvons discuter que de la mesure intérieure et de la mesure extérieure de l'évenément. En plus d'éliminer la nécessité d'assigner une probabilityéà l'événement, cette nouvelle approche apporte une réponse aux autres critiques des approches à l'incertitude basées sur des probabilityés. Par exemple, la mesure de croyance dans un événement est représentée par un intervalle (défini par la mesure intérieure et extérieure) plutǒt que par un nombre unique. De plus, cette approche nous permet d'assigner une croyance (mesure intérieure) à un événement E sans se compromettre vers une croyance à propos de sa négation -E (puisque la mesure intérieure d'un événement et la mesure intérieure de sa négation ne sont pas nécessairement une seule et unique mesure). II est intéressant de noter que les mesures intérieures qui résultent des mesures de probabilityé correspondent d'une manière précise aux fonctions de croyance de Dempster-Shafer. En plus de constituer un nouvel outil conceptuel prometteur dans le traitement de l'incertitude, cette approche démontre qu'une partie importante de la théorie de l'évidence de Dempster-Shafer est fermement ancrée dans la theorie classique des probabilityés.  相似文献   
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A cryo-specimen storage system for low-temperature scanning electron microscopy (LTSEM) specimens is described, which: liberates multi-specimen experiments from sampling restrictions imposed by the rate at which LTSEM specimens can be examined in the SEM; provides security against experiment loss resulting from breakdown of the SEM or cryo-system; enables collection of specimens in the field or in laboratories remote from the SEM laboratory; and facilitates international air transport of LTSEM specimens. The components of the system, which has a capacity of 98 stub-mounted specimens, are readily made in a laboratory workshop. The details of the design may be altered to suit particular specimen types or experimental approaches.  相似文献   
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Counting Objects   总被引:1,自引:0,他引:1  
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A screening procedure utilizing boysenberry juice as a substrate, which combined HPLC and spectrophotometric analyses, was used to measure β-glucosidase activity of enzyme preparations used for juice processing. Enzyme preparations (n = 26) were evaluated at two dosage rates. At the mean recommended dosage, one preparation produced a decrease in total monomeric anthocyanin and cyanidin-3-glucoside, relative to a control, indicating β-glucosidase activity. At 0.1% dosage, 4 enzymes produced a significant decrease in cyanidin-3-sophoroside and 2 enzymes caused an increase in cyanidin-3-rutinoside, indicating β-1,2-glucosidase activity. Such activity in juice processing enzymes was much lower and less prevalent than found previously for β-galactosidase. Botrytis cinerea also degraded anthocyanins in boysenberry juice.  相似文献   
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Meat acquires a characteristic microflora after slaughter and butchering. This normal microflora may be beneficial in that it occupies a niche that would otherwise permit unimpeded growth of potential pathogens. Lactic acid decontamination (LAD) is intended to eliminate pathogens but also affects the normal microflora. The immediate effect was studied by means of an in-vitro model. Experiments using this model achieved a reduction in the mesophilic Enterobacteriaceae on meat by 1 to 3 log10 colony forming units and shifted the predominant microflora in the direction of Gram-positive bacteria and yeasts. Colony counts were an unreliable indicator of LAD-induced reductions in Gramnegative foodborne pathogens. Their reduction depended on the ratio of the more lactic acid resistant Gram-positive bacteria to the more sensitive Gram-negative bacteria. The rank order of lactic acid-resistance of nonpathogens present on meat was yeasts = lactobacilli > psychrotrophic Gram-positive bacteria > mesophilic Enterobacteriaceae. Psychrotrophic Gram-negative bacteria were the most sensitive.  相似文献   
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