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11.
Effect of combined microwave (MW) and enzymatic hydrolysis on the human immunoglobulin E (IgE)-binding properties of ??-lactoglobulin (??-lg) and other whey proteins (WP) was investigated. Separated ??-lg and full whey protein isolate (WPI) were hydrolyzed with trypsin, chymotrypsin, mixture of trypsin/chymotrypsin, and pepsin at three microwave power levels: 50?W during 1 and 5?min, 100 and 200?W during 1 and 3?min. The immunoreactivity of the obtained hydrolysates resulting from combined microwave protease treatment was assessed using sera of young patients allergic to bovine whey proteins. The application of microwave treatment at 200?W enhances the hydrolysis of ??-lg by pepsin in 3?min and decreases significantly its immunoreactivity. The extensive hydrolysis of the microwave-treated ??-lg and WPI with trypsin, chymotrypsin, and the mixture of trypsin with chymotrypsin did not have an impact on the IgE binding of the products obtained in all the studied conditions.  相似文献   
12.
In this paper we deal with misbehaving nodes in mobile ad hoc networks (MANETs) that drop packets supposed to be relayed, whose purpose may be either saving their resources or launching a DoS attack. We propose a new solution to monitor, detect, and safely isolate such misbehaving nodes, structured around five modules: (i) The monitor, responsible for controlling the forwarding of packets, (ii) the detector, which is in charge of detecting the misbehaving of monitored nodes, (iii) the isolator, basically responsible for isolating misbehaving nodes detected by the detector, (iv) the investigator, which investigates accusations before testifying when the node has not enough experience with the accused, and (v) finally the witness module that responds to witness requests of the isolator. These modules are based on new approaches, aiming at improving the efficiency in detecting and isolating misbehaving nodes with a minimum overhead. We describe these modules in details, and their interactions as well. We also mathematically analyze our solution and assess its performance by simulation, and compare it with the watchdog, which is a monitoring technique employed by almost all the current solutions.  相似文献   
13.
This paper investigates a new front-end processing that aims at improving the performance of speech recognition in noisy mobile environments. This approach combines features based on conventional Mel-cepstral Coefficients (MFCCs), Line Spectral Frequencies (LSFs) and formant-like (FL) features to constitute robust multivariate feature vectors. The resulting front-end constitutes an alternative to the DSR-XAFE (XAFE: eXtended Audio Front-End) available in GSM mobile communications. Our results showed that for highly noisy speech, using the paradigm that combines these spectral cues leads to a significant improvement in recognition accuracy on the Aurora 2 task.  相似文献   
14.
The paper centres on the use of the so-defined LEIS approach (Large-Eddy & Interface Simulation) for turbulent multifluid flows present in thermal-hydraulics applications. Interfacial flows involving deformable, sheared fronts separating immiscible fluids are shown to be within reach of this new approach, featuring direct resolution of turbulence and sheared interface deformations within the interface tracking (ITM) framework, such as level sets and VOF. In this technique supergrid turbulence and interfacial scales are directly solved whereas the sub-grid (SGS) parts are modelled, at least the turbulence part of it. First results are shown (feasibility), and difficulties and open issues are discussed. The connection between these two particular scales will also be discussed, and potential modelling routes evoked, including combining two-fluid and ITM, local grid refinement, or combing particle tracking and ITM for sub-grid inclusions smaller than the grid size.  相似文献   
15.
Whey proteins adjusted at pH values 2, 4.6, 9 and at the natural milk pH (pH 6.8) were subjected to microwave irradiation at 300 W for 20 min or 700 W for 10 min. The protein composition of treated and native whey proteins were evaluated by Lowry’s method and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The ability of treated whey to bind IgG polyclonal antibody was determined by an enzyme-linked immunosorbent assay (ELISA) using sera obtained from rabbit immunized to β-Lactoglobulin (β-Lg). Significantly higher losses in soluble protein concentrations were observed for microwave irradiated whey proteins at pH value 4.6 (35.6% at 300 W and 44.33% at 700 W) (P < 0.0001) compared with those irradiated at the natural milk pH (26% at 300 or 700 W). The electrophoretic patterns of these proteins revealed a considerable decrease in intensity of the band corresponding to α-lactalbumin but only a slight modification was observed for the electrophoretic profiles of β-lactoglobulin. The data obtained with a rabbit anti-β-lactoglobulin immunoglobulin indicated a low antigenic response for microwave-irradiated whey proteins at the natural milk pH (up to 29.32% as well as 300–700 W) (P < 0.001). The lowest antigenicity was observed for samples adjusted to pH 4.6 followed by microwave irradiation at 300 or 700 W (46.99% at 300 W and 41.16% at 700 W) (P < 0.0001).  相似文献   
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17.
2008年,法国政府发起"后京都议定书时代大都市"和"未来都市巴黎"的研究,l'AUC事务所入选10家国际团队作为大巴黎研究项目的咨询顾问。本文展示了l'AUC事务所的方案及其他4个项目,分别针对当代规划、城市主义和建筑不同方面的主要问题:回收,生态城,紧凑和节点城市。  相似文献   
18.
Knowledge of endogenous ligands of olfactory binding proteins is a prerequisite for studying their role in odor and pheromone transduction. Here, we report the extraction, derivatization, and characterization by gas chromatography-mass spectrometry of the natural ligands of pig, Sus scrofa (L.), Von Ebner’s Gland protein (VEG) and odorant binding protein (OBP). We identified two isoforms (VEG1 and VEG2), which differed only by the linkage of an O-N-acetylglucosamine (O-GlcNac) group on VEG1. The natural ligands of VEG1 were characterized as two isomers of testosterone, whereas ligands of VEG2 and OBP were fatty acids or their derivatives. Our findings suggest that the binding specificity of VEG1 for steroids is governed by the presence of an O-GlcNac moiety on the protein. This specificity was confirmed by the binding of radiolabeled testosterone only by VEG1 in an in-gel binding assay. This is the first evidence for a post-translational modification in the process of odorant discrimination by olfactory binding proteins.  相似文献   
19.
Hydroxyapatite (HA) coating with nanoparticles like nanorice is fabricated on chemically pretreated titanium (Ti) surface, through an electrochemical deposition approach, for biomaterial applications. The Ti surface was chemically patterned with anatase TiO2 nanofibers. These nanofibers were prepared by in situ oxidation of Ti foils in a concentrated solution of H2O2 and NaOH, followed by proton exchange and calcinations. Afterward, TiO2 nanofibers on Ti substrate were coated with HA nanoparticles like nanorice. The obtained samples were annealed at high temperature to produce inter diffusion between TiO2 and HA layers. The resultant layers were characterized by Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), X-ray Photoelectron Spectroscopy (XPS), X-ray Diffraction (XRD), Infrared Spectroscopy (FTIR), corrosion tests in SBF solution, and Electron Probe Micro Analysis (EPMA). It was found that only Ti from the titanium substrate diffuses into the HA coating and a good corrosion resistance in simulated body fluid was obtained.  相似文献   
20.

Recent decades have witnessed the birth of major applications of wireless communication technology, further supported by the increasing capabilities of portable devices, low cost and ubiquitous presence. Despite radio technology diversity, a great deal of existing research focuses on a single and isolated wireless technology at a time, where homogeneous elements are identified by IP addresses. This work presents a heterogeneous technology routing (HTR) Framework, targeted towards scenarios where the heterogeneity of devices and networking technologies is present. Our contribution is many fold. It consists of a framework, which encompasses a process for bootstrapping networks, a routing protocol capable of dealing with multiple network interfaces, and a tuning with multipath extensions. We evaluate the performance of the bootstrap, routing and multipath mechanisms by way of simulation and an actual testbed implementation. The multipath evaluation simulates HTR networks with WiMAX, 3GPP LTE and Wi-Fi support. Results show that our proposal can effectively improve the data delivery ratio for ad-hoc networks and that it reduces the end-to-end delay without major impact on network energy consumption. As part of HTR tuning, we investigate next the impacts of tuning the HELLO refresh interval timer on route convergence and its subsequent energy consumption reduction during this phase. We also compare our tuned HTR with the widely used optimized link state routing protocol. Results show that varying the HELLO refresh interval can improve the convergence time and reduce the energy consumption without major impact on network behavior. Our proposal also includes a new distributed address allocation algorithm, namely, the dynamic node configuration protocol (DNCP). This paper conducts a comparative analysis between the Prime, Prophet and the DNCP schemes using static and dynamic topologies in terms of network setup time, energy consumption and control message overhead. Results show that the DNCP had a lower battery power consumption and less control message overhead while it slightly suffers with regard to setup.

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