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91.
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To determine whether faecal microorganisms can represent the entire large intestinal population, samples from caecum, mid‐colon and rectum of three adult pigs were used for the in vitro fermentation of fructo‐oligosaccharide (FOS), potato starch, wheat bran and oat hulls. The cumulative gas production technique measured fermentation kinetics and end‐products such as total gas, NH3 and volatile fatty acids (VFA). There were significant differences in the fermentability of substrates, in terms of both kinetics and end‐products. More relevant to this study, there were also differences between pigs in respect of total gas production, the rate of gas production (RM) and VFA production. For large intestine sections, there were more VFA from mid‐colon and rectal inocula compared with that from the caecum (p < 0.0001). Total gas, RM and NH3 were highest for rectal, intermediate for mid‐colon and lowest for caecal inocula (p < 0.0001). It was concluded that, while faecal sampling might overestimate caecal fermentation, its use is valid for in vitro assessment of large intestinal fermentation. However, differences between pigs indicate that a mix of samples from several animals remains important. Copyright © 2004 Society of Chemical Industry  相似文献   
93.
A trial was set up in northern Benin to evaluate the potential of Teretrius nigrescens to reduce the infestation and damage to cassava chips caused by storage insects. Cassava chips were stored for 5 months in mud silos and 50 adults of T. nigrescens were added when the stores were first filled. Stores where no predator was released were monitored as controls. The main storage insects observed were Prostephanus truncatus and Dinoderus spp. Initial chip weight varied between 102 and 246 g with no difference between treatments. Chip weight and number of holes on chips initially differed between treatments after 2 months of storage. After 3 months of storage, losses reached 40-50% without T. nigrescens and 30-40% when cassava chips were stored with T. nigrescens. A farmer can increase his profit by 1437 Fcfa/100 kg (1$=560 Fcfa, 1£=968 Fcfa; 1€=656 Fcfa, as on 2 December 2005) through the use of T. nigrescens because losses are reduced by 11%. Data analysis showed that there were significant differences (P<0.0001) between the two treatments for the number of holes, number of insects, weight of each chip as well as damage. There were twice as many P. truncatus and holes on chips in stores where T. nigrescens was not released. The addition of the predator to farmers’ stores is an economic option for controlling losses due to insects in cassava chips.  相似文献   
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Effects of tumbling and RN genotype on sensory perception of cured-smoked loins were studied on loins from 32 crossbred female pigs containing Hampshire blood. Right-side loins were intermittently tumbled during 4 h, whereas left-side loins were left non-tumbled. Tumbled loins were more tender and uniform in cured colour as well as less acidulous in taste compared with non-tumbled loins. Further, the formation of undesirable pores was lower in tumbled loins. Final juiciness tended to be higher and meat taste intensity lower in tumbled loins, whereas initial juiciness did not differ. There were no significant interactions between tumbling and RN genotype for sensory attributes. RN carriers (RN/rn+) were more acidulous in taste, had more pronounced meat taste and were saltier than non-carriers (rn+ /rn+). Moreover, they tended to have higher initial juiciness and more undesirable pores, and be less homogeneous in cured pink colour. No differences in consumer preference between the four treatments were detected in the ranking test, but most persons ranked non-tumbled loins highest regarding overall liking. Instrumental tenderness measurements agreed well with sensory tenderness scores.  相似文献   
95.
The evolution of the velocity boundary layer during the initial phase of copper electrolysis under the influence of a magnetic field is studied by using particle image velocimetry and a novel laser Doppler velocity profile sensor. With this new sensor, time-resolved velocity measurements within 400 μm of a vertically aligned cathode in an aqueous 0.05 M CuSO4-solution are presented. In this way, the complex interaction of Lorentz force and opposing buoyancy-driven convection was studied by measuring the resulting velocity profile inside the concentration boundary layer with a spatial resolution of 15 μm. It is shown that the Lorentz force-driven convection only dominates the velocity boundary layer during the early phase of electrolysis and induces a linear velocity profile near the cathode. The linear relationship between the velocity gradient and Lorentz force is determined. With the onset of the opposing buoyancy-driven convection at the cathode, a duplex structure of the boundary layer appears. Its characteristic quantities, given by the horizontal distances, δmax and δv=0, where the velocity reaches the maximum and where it is equal to zero, remain nearly unchanged, while the maximum velocity, vmax, in spite of the counteracting Lorentz force, increases faster as compared to pure natural convection, depending on the current density.  相似文献   
96.
This study focuses upon the heterogeneity in the contemporary workforce in relation to well-being and organizational attitudes. This heterogeneity may concern (a) the specific type of contract (permanent full-time vs. alternative arrangements; e.g., permanent part-time, fixed-term, and on-call work), (b) job and contract preferences, or (c) specific combinations of contract type and preferences. The authors argue that working in alternative employment, but also being in a nonpreferred contract or job may imply stress and, hence, strain (i.e., poor well-being). This may lead to withdrawal from the organization (i.e., poor organizational attitudes). A combination of the stressors may strengthen these effects. Analyses of questionnaire data from Sweden collected in 2004 (N = 716) reveal that preferences, particularly preferences for the job and partly also for the contract, were associated with the outcomes. Contract heterogeneity was not informative for well-being, while it was for differences in reported organizational attitudes. Type of employment contract interacted with job and contract preferences: for permanent full-time workers, job preferences displayed stronger associations with well-being and attitudes than for workers in alternative employment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The interdisciplinary Tales of Things and electronic Memory (TOTeM) project investigates new contexts for augmenting things with stories in the emerging culture of the Internet of Things (IoT). Tales of Things is a tagging system which, based on two-dimensional barcodes (also called Quick Response or QR codes) and Radio Frequency Identification (RFID) technology, enables the capturing and sharing of object stories and the physical linking to objects via read and writable tags. Within the context of our study, it has functioned as a technology probe which we employed with the aim to stimulate discussion and identify desire lines that point to novel design opportunities for the engagement with personal and social memories linked to everyday objects. In this paper, we discuss results from fieldwork with different community groups in the course of which seemingly any object could form the basis of a meaningful story and act as entry point into rich inherent ‘networks of meaning’. Such networks of meaning are often solely accessible for the owner of an object and are at risk of getting lost as time goes by. We discuss the different discourses that are inherent in these object stories and provide avenues for making these memories and meaning networks accessible and shareable. This paper critically reflects on Tales of Things as an example of an augmented memory system and discusses possible wider implications for the design of related systems.  相似文献   
100.
More effective methods of eliciting and summarizing stakeholders' goals can assist in improving watershed management. This paper discusses the process of summarizing the goals that were generated during a workshop of watershed stakeholders in Virginia by using the Vector Analytic Hierarchy Process, and then grouping them into homogeneous subgroups by using two different methods: 1) assigning subgroups based on individuals' stated affiliations from a participant bio-sheet; and 2) assigning subgroups based on the similarity of individuals' actual preferences between the goals. Several different clustering approaches are considered for creating the preference-based subgroups, and the relative advantages and disadvantages of each approach are discussed. The process of combining the subgroups to generate a single overall preference structure for the group as a whole is also considered, and the final results are compared based on both the resulting rankings and the coherence, or variability of opinion, that they reflect. Determining the “best” set of subgroups can be valuable not only in exploring the underlying nature of the population's preferences, but also in supporting additional discussion and analysis of the results. As such, it can ultimately lead to much stronger and better informed decision-making by the stakeholders.  相似文献   
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