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81.
In the present study, a novel method of measuring the uptake of nutrients by 1H NMR spectroscopy was performed to determine dietary effects. Six pigs catheterized in the portal vein and mesenteric artery were fed breads made from whole-wheat grain (WWG), wheat aleurone flour (WAF; 19?% aleurone of bread) or rye aleurone flour (RAF; 15?% aleurone of bread) in a repeated 3?×?3 crossover design. Three meals were provided daily (at 0, 5 and 10?h), and each period comprised of 1?week. Portal and arterial blood samples were collected at fasting (?30?min) on day 4–7, and on day 7, pooled blood samples were collected at 0–2.5, 2.5–5, 5–7.5 and 7.5–10?h after first (0?h) daily meal. Using the arterial-venous difference and ANOVA–simultaneous component analysis, plasma betaine was found to accumulate during the experimental period. On day 7, plasma betaine concentrations was 20–40?% higher than when feeding the WAF diet compared with RAF and WWG (P?=?0.001), whereas the content of betaine in the WAF diet was about twice as high. The arterial-venous difference showed a tendency (P?=?0.078) for the diet–time interaction of betaine absorption in the absorption phases but there was no diet effect (P?=?0.31), which indicates a steady-state absorption has been reached on day 7. Furthermore, high plasma betaine levels correlated with low plasma creatine of endogenous origin. In conclusion, the explorative method revealed that the plasma concentration and absorption of betaine were differentially modified by the diets.  相似文献   
82.
ABSTRACT

The article analyzes Tidal River Management in Bangladesh from a social learning perspective. Four cases were investigated using participatory assessment. Knowledge acquisition through transformations in the Tidal River Management process was explored as an intended learning outcome. The study finds that social learning occurred more prominently at the individual stakeholder level and less at the collective level. For Tidal River Management to be responsive and sustainable, especially in times of increased uncertainty and climate vulnerability, more attention needs to be paid to coordination and facilitation of multi-level learning that includes all stakeholders.  相似文献   
83.
The trachea has a complex anatomy to fulfill its tasks. Its unique fibro-cartilaginous structure maintains an open conduit during respiration, and provides vertical elasticity for deglutition, mobility of the neck and speech. Blood vessels pierce the intercartilaginous ligaments to perfuse the ciliated epithelium, which ensures effective mucociliary clearance. Removal of a tracheal segment affected by benign or malignant disease requires airtight restoration of the continuity of the tube. When direct approximation of both tracheal ends is no longer feasible, a reconstruction is needed. This may occur in recurrent short-segment defects in a scarred environment, or in defects comprising more than half the length of the trachea. The resulting gap must be filled with vascularized tissue that restores the mucosal lining and supports the semi-rigid, semi-flexible framework of the trachea. For long-segment or circular defects, restoration of this unique biomechanical profile becomes even more important. Due to the inherent difficulty of creating such a tube, a tracheostomy or palliative stenting are often preferred over permanent reconstruction. To significantly improve and sustain quality of life of these patients, surgeons proposed innovative strategies for complex tracheal repair. In this review, we provide an overview of current clinical applications of tracheal repair using autologous and allogenic tissues. We look at recent advances in the field of tissue engineering, and the areas for improvement of these first human applications. Lastly, we highlight the focus of our research, in an effort to contribute to the development of optimized tracheal reconstructive techniques.  相似文献   
84.
85.
There are various methods for measuring flow rates in rivers, but all of them have practical issues and challenges. A period of exceptionally high water levels revealed substantial discrepancies between two measurement setups in the same waterway. Finding a causal explanation of the discrepancies was important, as the problem might have ramifications for other flow-rate measurement setups as well. Finding the causes of problems is called diagnostic problem-solving. We applied a branch-and-prune strategy, in which we worked with a hierarchy of hypotheses, and used statistical analysis as well as domain knowledge to rule out options. We were able to narrow down the potential explanations to one main suspect and an alternative explanation. Based on the analysis, we discuss the role of statistical techniques in diagnostic problem-solving and reasoning patterns that make the application of statistics powerful. The contribution to theory in statistics is not in the individual techniques but in their application and integration in a coherent sequence of studies – a reasoning strategy.  相似文献   
86.
Soft robots are an interesting alternative for classic rigid robots in applications requiring interaction with organisms or delicate objects. Elastic in?atable actuators are one of the preferred actuation mechanisms for soft robots since they are intrinsically safe and soft. However, these pneumatic actuators each require a dedicated pressure supply and valve to drive and control their actuation sequence. Because of the relatively large size of pressure supplies and valves compared to electrical leads and electronic controllers, tethering pneumatic soft robots with multiple degrees of freedom is bulky and unpractical. Here, a new approach is described to embed hardware intelligence in soft robots where multiple actuators are attached to the same pressure supply, and their actuation sequence is programmed by the interaction between nonlinear actuators and passive ?ow restrictions. How to model this hardware sequencing is discussed, and it is demonstrated on an 8‐degree‐of‐freedom walking robot where each limb comprises two actuators with a sequence embedded in their hardware. The robot is able to carry pay loads of 800 g in addition to its own weight and is able to walk at travel speeds of 3 body lengths per minute, without the need for complex on‐board valves or bulky tethers.  相似文献   
87.
Multimedia Tools and Applications - Recording videos with smartphones at large-scale events such as concerts and festivals is very common nowadays. These videos register the atmosphere of the event...  相似文献   
88.
Network and service management is an established research field within the general area of computer networks. A few years ago, an initial taxonomy, organizing a comprehensive list of terms and topics, was established through interviews with experts from both industry and academia. This taxonomy has since been used to better partition standardization efforts, identify classes of managed objects and improve the assignment of reviewers to papers submitted in the field. Because the field of network and service management is rapidly evolving, a biyearly update of the taxonomy was proposed. In this paper, a large-scale questionnaire is presented which was answered by experts in the field, evaluating the relevance of each individual topic for the next five years. Missing topics, which are likely to become relevant over the next few years, are identified as well. Furthermore, an analysis is performed of the records of papers submitted to major conferences in the area. Based on the obtained results, an updated version of the taxonomy is proposed.  相似文献   
89.
Untethered soft actuators are usually based on 3D engineered special polymers such as liquid crystal networks or hydrogels that require complex fabrication methods. Here, an easy-to-process, anisotropic composite soft actuator based on a simple photothermal dye-doped polyethylene film is presented. The 3D anisotropic polymer films are prepared by solution-casting and subsequent thermal solid-stretching. The resulting soft actuators exhibit large and controllable bending in response to light (UV and/or near-infrared (NIR)) and are able to act as grippers picking up cargo. Additionally, the films are capable of realizing “diving” and “surfing” locomotion in and over a liquid via the photothermal induced Marangoni effect, yielding a NIR light-fueled transporter able to pick up cargo. The results open up new possibilities of using commodity polymers in a broad range of applications including untethered soft actuators and robotic devices.  相似文献   
90.
Wireless Personal Communications - Private professional environments such as manufacturing industry, warehouses, hospitals, airports, among others, increasingly rely on end-to-end connected...  相似文献   
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