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11.
This paper presents a low-power wakeup radio (WUR) for application in indoor location systems. The presented radio has a better performance than the state-of-the-art radios, since it has low-power consumption, only 10 μW and it is perfectly integrated into a wireless sensor network based on ZigBee, which is used for location purposes. This performance was achieved due to an optimised radio frequency design of the WUR, which was embedded with a low-cost/low-power processor, and due to an enhanced control algorithm. Moreover, a software defined radio approach has been used to implement the WUR protocol. The WUR was designed and integrated in an existing WSN-based indoor location system which was originally based on a periodic sleep-wake up duty-cycled protocol. In the WUR protocol the location sensor is kept in deep sleep mode until it receives an external wake-up order. According to estimates, with this scheme, the battery lifetime can be increased from 200 days (using conventional duty-cycle protocol) up to almost 8000 days (sensor waken-up few times per day).  相似文献   
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Vehicular Delay-Tolerant Networking (VDTN) is a Delay-Tolerant Network (DTN) based architecture concept for transit networks, where vehicles movement and their bundle relaying service is opportunistically exploited to enable non-real time applications, under environments prone to connectivity disruptions, network partitions and potentially long delays. In VDTNs, network resources may be limited, for instance due to physical constraints of the network nodes. In order to be able to prioritize applications traffic according to its requirements in such constrained scenarios, traffic differentiation mechanisms must be introduced at the VDTN architecture. This work considers a priority classes of service (CoS) model and investigates how different buffer management strategies can be combined with drop and scheduling policies, to provide strict priority based services, or to provide custom allocation of network resources. The efficiency and tradeoffs of these proposals is evaluated through extensive simulation.  相似文献   
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This research verified the ability of Lactobacillus rhamnosus encapsulated with inulin to tolerate the simulated digestive system and their viability in a soy blend. Probiotic encapsulated in alginate-chitosan matrix without inulin presented a better encapsulation efficiency (80.92%) than encapsulation with inulin (57.39%). On the 28th day, the count of probiotics decreased by 3.42 and 1.99 logarithmic cycles of free and encapsulated cells without inulin, respectively. In contrast, the microorganisms encapsulated with inulin showed an increase of 1.26 logs CFU g−1. During gastrointestinal simulation, cell counts decreased by 0.78, 1.55 and 1.95 CFU g−1 logs for encapsulated cells without inulin, free and encapsulated with inulin, respectively. Sensory panellists liked the fermented soy blend with encapsulated lactobacilli, and this result shows the possibility to create new probiotic foods of plant origin. Therefore, the alginate/chitosan matrix can be considered adequate for the encapsulation of L. rhamnosus. The inulin reduces the encapsulation efficiency and increases the cell loss in gastrointestinal simulation. Considering cellular losses, the best option for preparing a fermented soy blend is to use L. rhamnosus encapsulated without inulin.  相似文献   
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This study aimed to evaluate the vacuum impregnation (VI) and soaking methods in the addition of Lactobacillus acidophilusLA‐3 to minimally processed melon (MPM). The melons were washed, sanitised in chlorine solution (200 mg L?1), peeled and cutted into cubes. Lactobacillus acidophilusLA‐3 (1.4 × 1010 CFU g?1) were added to the MPM through both techniques. The L. acidophilusLA‐3 count in MPM was similar to those commonly found in dairy products having probiotic claim, but VI was more efficient than soaking in maintaining the viability (8.61 and 7.98 Log CFU g?1, respectively). The pH, acidity and soluble solids were not affected by probiotic culture and the incorporation technique; however, the VI affected the firmness of fruit. The MPM was within Brazilian standards for their microbiological characteristics. MPM may be used as a carrier of probiotic bacteria, being one more alternative for individuals who consume probiotic products.  相似文献   
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Nonconventional raw materials have been applied in gluten‐free pasta, to meet the demand of people with coeliac disease. The objective of this study was to evaluate the cooking properties and texture of pasta formulated with rice flour, defatted flaxseed flour and pregelatinised mixed flour of rice and flaxseed (80:20). For this experiment, simplex design was used. Cooking properties and texture were found within the quality limits established for this type of product. The pasta with the most desirable properties (short optimum cooking time (OCT), less solid loss (SL) and intermediate mass increase (MI)) was that one formulated with 43 g 100 g?1 of pregelatinised flour, 47 g 100 g?1 of rice flour and 10 g 100 g?1 of defatted flaxseed flour. This formulation can be characterised as a food rich in dietary fibre and of high nutritional value.  相似文献   
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The antioxidant capability and total phenolic contents of methanolic extracts of Agaricusbrasiliensis in two stages of maturity, young (YB) and mature (MB), were evaluated in this work. Four complementary assays, reducing power, radical scavenging capacity, inhibition of lipid peroxidation and chelating ability for ferrous ions were used to screen the antioxidant properties of extracts. Minor differences in the composition of phenolic compounds were detected, but the extracts showed similar antioxidant activities, except for the chelating ability for ferrous ions, higher in MB than in YB. Our results support the use of both young and mature fruiting bodies of Agaricus blazei as sources of antioxidant compounds.  相似文献   
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Sugarcane spirit is the most consumed distilled beverage in Brazil. Currently the manufacturing industries are trying to widen their market and attract new consumers, and thus it has become necessary to elevate the product to national and international quality standards. This study's aim was to determine the influence of subsequent distillations on the composition of organic sugarcane spirit. From mono‐distilled organic sugarcane spirit, bi‐, tri‐, tetra‐ and penta‐distilled sugarcane spirits were obtained, and analysed for the following: relative density, alcoholic degree, volatile acidity, pH, copper, methanol, aldehydes, furfural, esters, ethyl carbamate and higher alcohols. The most relevant results were reductions of 69.57% volatile acidity, 98.4% copper, 40.9% methanol, 71.5% aldehydes, 100% esters, 100% ethyl carbamate and 32.2% higher alcohols in the penta‐distilled sugarcane spirit, as compared with the mono‐distilled. It was concluded that subsequent distillations would put sugarcane spirit in line with the international standards for distilled beverages. Copyright © 2013 The Institute of Brewing & Distilling  相似文献   
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