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131.
A growing number of diseases in association with gluten intake, such as coeliac disease, have led to increasing demand for gluten-free products as a crucial economic and health issue. Gluten-free products, because of the absence of gluten, usually have a poor texture, taste and appearance. Therefore, the production of good quality gluten-free products with substances that can somehow mimic the viscoelastic properties of gluten is an important challenge. Recently, hydrocolloids are widely used to improve the quality and shelf-life of gluten-free products. In this study, the effect of hydrocolloids on the production of gluten-free cereal-based products, such as breads, cakes and muffins, biscuits and cookies, pasta and noodles, has been reviewed as well as their nutritional values. In general, this study could suggest key factors in the improvement of gluten-free products.  相似文献   
132.
An optimized Ternary CAM concept is introduced for the hardware search engines in high-speed Internet routers. Our design employs w + 1 RAM bits to store a word of size w, whereas a conventional TCAM needs 2w RAM bits for the same word size. Based on this concept an 8-bit cluster is designed out of 9 SRAM bits, used as the basic building block of our Prefix-CAM (PCAM) structure. Four such clusters merge to store a 32-bit IPv4 prefix, thus, configuring a PCAM suitable for Internet packet forwarding. This PCAM module employs 48% less SRAM cells and a total of 22% less transistors plus 50% less address decode interconnects compared to a conventional TCAM, for equal storage size and equal functionality. We show that PCAM can be employed for multifield packet classification. Other factors, such as lookup speed and power dissipation, are not adversely affected.  相似文献   
133.
Iran produces about 7000 metric tons of cumin seed meal (CSM) as a by‐product of cumin oil extraction factories, annually. To evaluate the nutritional significance of cumin seed meal as a broiler feedstuff, an experiment was conducted using 288 male broiler chicks (14 days old) receiving diets containing 0, 25 and 50 g kg−1 of CSM with and without polyethylene glycol (PEG) and enzyme (Grindazyme GP 15000) for 28 days. Total body weight (BW), body weight gain (WG), feed intake (FI), feed conversion ratio (FCR), weight of carcass and percentage of legs, breast and edible parts of carcass were measured. The results showed that, inclusion of CSM in broiler diets had no negative influence on parameters evaluated compared to the control diet containing wheat bran (P > 0.05). PEG and enzyme had no influence on the bird performance (P > 0.05). There was an increase in relative weight of gizzard when the amount of CSM in the diet was increased (P < 0.01). An increase in relative weight of gizzard in birds that received the CSM diet was likely to be due to the increase in fibre content of CSM diets. In respect of the low price of CSM, it could be concluded that inclusion of CSM at levels used in this experiment has no negative effect on broiler performance and reduces the overall cost of broiler production. Copyright © 2006 Society of Chemical Industry  相似文献   
134.
On the nature of tip clearance flow in subsonic centrifugal impellers   总被引:1,自引:0,他引:1  
Increasing demand for downsizing of engines to improve CO2 emissions has resulted in renewed efforts to improve the efficiency and expend the stable operating range of the centrifugal compressors used in petro-chemical equipment and turbochargers. The losses in these compressors are dominated by tip clearance flow. In this paper, the tip clearance flow in the subsonic impeller is numerically investigated. The nature of the tip clearance in inducer, axial to radial bend and exducer are studied in detail at design and off-design conditions by examining the detailed flow field through the clearance and the interaction of the clearance flow with the shear effect with the endwalls. The correlation between blade loading and span wise geometry and clearance flow at different locations are presented.  相似文献   
135.
Over the last decade, nanocomposite hydrogels have been provided a new approach for the biomedical field. In this work, a novel pH-responsive nanocomposite hydrogel was fabricated using simultaneous in situ formation of magnetite iron oxide nanoparticles and hydrogel networks of poly(acrylic acid) grafted onto chitosan. The effects of various types of precursor molecules, pH, salt, and loading pressure were examined on the swelling properties of resulting nanocomposite hydrogels. The synthesized nanocomposite hydrogel was well characterized using different instruments. In vitro drug releasing behavior of doxorubicin was studied at pH 5.4 and 7.4. The drug release mechanism was investigated through different kinetic models. These experimental results open a new opportunity to make pH-responsive nanocomposite hydrogel devices for controlled delivery of drug.  相似文献   
136.

In case there is a communication contrary to the system security policies, a covert channel has been created. The attacker can easily disclosure information from the victim’s system with just one public access permission. Covert timing channels, unlike covert storage channels, do not have memory storage and they draw less attention. Different methods have been proposed for their identification, which generally benefit from the shape of traffic and the channel’s regularity. The application nature of HTTP protocol allows the creation of a covert timing channel based on different features of this protocol (or different levels) that has not been addressed in previous researches. This research tries to study the effect of using different features (or levels) of HTTP protocol on identifying the covert channel. The amount of channel’s entropy could be manipulated by changing the channel’s level or adding intentional noise on the channel to protect from the analyzer’s detection. The difference in the placement of the covert channel and the detector causes the amount of channel entropy to be far from the detection threshold. Therefore, we concluded that the analyzer must investigate traffic at all possible levels. Adding noise on the covert channel decrease its capacity, but as entropy increases, it would be harder to detect it.

  相似文献   
137.
Recently, social networking sites are offering a rich resource of heterogeneous data. The analysis of such data can lead to the discovery of unknown information and relations in these networks. The detection of communities including ‘similar’ nodes is a challenging topic in the analysis of social network data, and it has been widely studied in the social networking community in the context of underlying graph structure. Online social networks, in addition to having graph structures, include effective user information within networks. Using this information leads to enhance quality of community discovery. In this study, a method of community discovery is provided. Besides communication among nodes to improve the quality of the discovered communities, content information is used as well. This is a new approach based on frequent patterns and the actions of users on networks, particularly social networking sites where users carry out their preferred activities. The main contributions of proposed method are twofold: First, based on the interests and activities of users on networks, some small communities of similar users are discovered, and then by using social relations, the discovered communities are extended. The F-measure is used to evaluate the results of two real-world datasets (Blogcatalog and Flickr), demonstrating that the proposed method principals to improve the community detection quality.  相似文献   
138.
The level of muscle activity can be decreased with optimized foot wedge condition. The aim of this study was to evaluate the effect of different foot wedge conditions on the activity of selected lower extremity muscles during load lifting. Nine able‐bodied male subjects participated in this study. Electromyography activity of the vastus medialis (VM), vastus lateralis (VL), medialis gastrocnemius (MG), and soleus (SOL) muscles was recorded during dynamic load lifting using the squat technique in 5 conditions: i) non‐wedge (NW), ii) 1 cm heel height increasing (PW1), iii) 3 cm heel height increasing (PW3), iv) 1 cm in front of the feet (AW1), and v) 1 cm inside the feet (MW1). The results showed that the VM activity decreases in the MW1 compared to other conditions and significantly compared to the PW1 and PW3 conditions (p < .05). Decreases in the VL activity in the AW1 as well as in descending and ascending phases of MW1 were observed (p < .05). Also in the descending phase, the SOL activity in AW1 decreased significantly compared to NW condition (p < .05). However, there was no significant difference in MG activity between different conditions (p > .05). It seems that placing wedges in the anterior and medial area of the feet may decrease quadriceps muscles activity and probably can delay reaching time to fatigue during load lifting. These findings may be helpful in designing special shoes for ergonomics fields and work environments.  相似文献   
139.
Sheath blight disease in rice has caused major crop losses worldwide. Managing the causal agent of disease Rhizoctonia solani Kühn is difficult because of its broad host range and formation of sclerotia which can survive in harsh environmental conditions; therefore developing innovative disease management methods without application of hazardous chemicals has been considered as the main concern to maintain sustainable agriculture. This presented research has revealed the negative impact of silver nanoparticles (SNPs) on R. solani and disease progress both in vitro and in vivo. The adverse effects of the SNPs on R. solani are significantly dependent on the quantity of SNPs, sprayed at different concentrations in vitro. The highest inhibition level against sclerotia formation and mycelia growth are 92 and 85%, respectively, at a SNPs concentration of 50 ppm. In vivo glasshouse experiments also showed that SNPs at the same concentration favourably affects both the fresh and dry weight of rice plants with a remarkable suppressive effect on the lesion development in leaves.Inspec keywords: antibacterial activity, silver, nanoparticles, nanomedicine, plant diseases, cropsOther keywords: in vitro antifungal properties, in vivo antifungal properties, silver nanoparticles, rice sheath blight disease, major crop losses, causal agent, Rhizoctonia solani Kühn, sclerotia, harsh environmental conditions, disease management methods, hazardous chemicals, sustainable agriculture, negative impact, inhibition level, mycelia growth, in vivo glasshouse experiments, rice plants, suppressive effect, lesion development, leaves  相似文献   
140.
When structures undergo extreme loading conditions, the materials pass the elastic limits. Therefore, to preserve economy as well as safety, it is essential to perform a realistic elastoplastic analysis using the constitutive equations in plasticity. On the other hand, computing the stress alongside its associated variables on Gauss points is a delicate process and virtually the most important part of these analyses. In this study, an efficient stress-updating technique is presented for the constitutive rate equations of the pressure sensitive materials such as concrete, rock, soil and some kind of metals. Accordingly, the Drucker–Prager plasticity is utilized to consider the hydrostatic pressure in addition to the J 2-invariant of the deviatoric stress. Moreover, the isotropic and kinematic hardenings are used to take into account more realistic behavior of the materials. Finally, a wide range of numerical tests is carried out to show the performance of the presented method together with the application of the suggested formulations in elastoplastic analysis of a gravity dam.  相似文献   
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