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91.
Lactic acid bacteria strains were identified from wheat germ by 16S rRNA partial sequencing, subjected to RAPD-PCR typing and screened. Lactobacillus plantarum LB1 and Lactobacillus rossiae LB5 were used as starters to produce sourdough fermented wheat germ (SFWG). The chemical and nutritional characteristics of SFWG were compared to those of the raw wheat germ (RWG). Lipase activity in SFWG was ca. 2.6-fold lower than that found in RWG. As shown by SPME/GC/MS analysis, most of the volatile compounds derived from lipid oxidation during storage (40 days) were at markedly lower levels in SFWG compared to RWG. Fermentation of wheat germ increased of ca. 50% the concentration of free amino acids. Glu markedly decreased in SFWG, due to its conversion in GABA. The concentration of the anti-nutritional factor raffinose also decreased in SFWG. The in vitro protein digestibility, the concentration of total phenols, phytase and antioxidant activities were increased by fermentation.  相似文献   
92.
Wireless Personal Communications - The integration of everyday objects into the Internet represents the foundation of the forthcoming Internet of Things (IoT). Smart objects will be the building...  相似文献   
93.
Although the eukaryotic elongation factor eEF1A1 plays a role in various tumours, there is little information on its prognosis/therapeutic value in prostate carcinoma. In high-grade and castration-resistant prostate carcinoma (CRPC), the identification of novel therapeutic markers/targets remains a priority. The expression of eEF1A1 protein was determined in formalin-fixed, paraffin-embedded prostate cancer and hyperplasia tissue by IHC. The role of eEF1A1 was investigated in a cellular model using a DNA aptamer (GT75) we previously developed. We used the aggressive CRPC cancer PC-3 and non-tumourigenic PZHPV-7 lines. Cytotoxicity was measured by the MTS assay and eEF1A1 protein levels by in-cell Western assays. The mRNA levels of eEF1A1 were measured by qPCR and ddPCR. Higher expression of eEF1A1 was found in Gleason 7–8 compared with 4–6 tissues (Gleason ≥ 7, 87% versus Gleason ≤ 6, 54%; p = 0.033). Patients with a high expression of eEF1A1 had a worse clinical outcome. In PC-3, but not in PZHPV-7, GT75 decreased cell viability and increased autophagy and cell detachment. In PC-3 cells, but not in PZHPV-7, GT75 mainly co-localised with the fraction of eEF1A1 bound to actin. Overexpression of the eEF1A1 protein can identify aggressive forms of prostate cancer. The targeting of eEF1A1 by GT75 impaired cell viability in PC-3 cancer cells but not in PZHPV-7 non-tumourigenic cells, indicating a specific role for the protein in cancer survival. The eEF1A1–actin complexes appear to be critical for the viability of PC-3 cancer cells, suggesting that eEF1A1 may be an attractive target for therapeutic strategies in advanced forms of prostate cancer.  相似文献   
94.
Throughout the 1990s, Software Defined Radio (SDR) technology was viewed almost exclusively as a solution for interoperability problems between various military standards, waveforms and devices. In the meantime, Cognitive Radio (CR) – a novel communication paradigm which embodies SDR with intelligence and self-reconfigurability properties – has emerged. Intelligence and on-the-fly self-reconfiguration abilities of CRs constitute an important next step in the Communications Electronic Warfare, as they may enable the jamming entities with the capabilities of devising and deploying advanced jamming tactics. Similarly, they may also aid the development of the advanced intelligent self-reconfigurable systems for jamming mitigation. This work outlines the development and implementation of the Spectrum Intelligence algorithm for Radio Frequency (RF) interference mitigation. The developed system is built upon the ideas of obtaining relevant spectrum-related data by using wideband energy detectors, performing narrowband waveform identification, extracting the waveforms’ parameters and properly classifying the waveforms. All relevant spectrum activities are continuously monitored and stored. Coupled with the self-reconfigurability of various transmission-related parameters, Spectrum Intelligence is the facilitator for the advanced interference mitigation strategies. The implementation is done on the Cognitive Radio test bed architecture which consists of two military Software Defined Radio terminals, each interconnected with the computationally powerful System-on-Module.  相似文献   
95.
Minimum substrate loss is required for resist strip of high dose, ultra shallow junction implant for source/drain extensions. Silicon surface oxidation of downstream plasma resist strip results in silicon recess of the source/drain extension regions. This paper reports the study of silicon surface oxidation for different resist strip plasma chemistries and the effect of plasma strip process parameters such as power, pressure and temperature on silicon surface oxidation. A good agreement was found between optical ellipsometry, XPS (X-ray photoelectron spectroscopy) and TEM (transmission electron spectroscopy) for thickness measurement of very thin (<20 Å) oxide grown on silicon surface due to plasma exposure. Selectivity of crust breakthrough and resist removal over silicon oxidation was also discussed in this paper along with dopant loss.  相似文献   
96.
Inclusion between XML types is important but expensive, and is much more expensive when unordered types are considered. We prove here that inclusion for XML types with interleaving and counting can be decided in polynomial time in the presence of two important restrictions: no element appears twice in the same content model, and Kleene star is only applied to disjunctions of single elements.  相似文献   
97.
Scanning electron microscope evaluation could be criticized if the method adopted to correct for bias is not specified in the study design. Observers can draw conclusions from images unconsciously chosen to best support their research hypotheses, impairing the basic research principle of operator's impartiality. In this study, a systematic observation method has been described and verified for repeatability. The number and the observation points on a certain specimen have been predetermined using a scheme along with observation rules previously established in the research protocol. When our instrument is used at an operating magnification between 500× and 1,000× (corresponding to a frame of 250×190 µ and 120×90 µ, respectively), the method allowed 100% repeatable observation frames, with linear frame errors in finding an observation point of 12.5% in length and 16.8% in height. With modifications to accommodate research objective and statistical requirements, the method could be applied to many SEM observation study. SCANNING 32: 97–103, 2010. © 2010 Wiley Periodicals, Inc.  相似文献   
98.
When a layer of volatile liquid is exposed to a shear flow of inert gas, thermal patterns, in the form of interfacial ripples and bulk plumes, are created by the combined action of evaporative, shear-driven and surface-tension-driven instabilities. The topology of the interfacial thermal patterns is mainly influenced by the geometry of the evaporating surface, the thickness of the evaporating layer, the intensity of the shear flow and by the physic-chemical properties of the working fluid. In this paper, by means of numerical simulations, we focused our attention on the dynamics of the interfacial thermal patterns for different working fluids and thicknesses of the volatile liquid layer. This study has been performed in the frame of the ESA sponsored Space Program on heat and mass transfer CIMEX-1. The choice of the fluids—ethyl alcohol and FC72 (n-perfluorohexane)—the reference values for the inert gas flow rate, the thickness of the liquid layer as well as the geometrical features of the computational domain correspond exactly to the ones foreseen for the CIMEX-1 experiment. However, the main conclusions can be considered of more general validity.  相似文献   
99.
Artificial olfaction systems, which mimic human olfaction by using arrays of gas chemical sensors combined with pattern recognition methods, represent a potentially low-cost tool in many areas of industry such as perfumery, food and drink production, clinical diagnosis, health and safety, environmental monitoring and process control. However, successful applications of these systems are still largely limited to specialized laboratories. Sensor drift, i.e., the lack of a sensor’s stability over time, still limits real industrial setups. This paper presents and discusses an evolutionary based adaptive drift-correction method designed to work with state-of-the-art classification systems. The proposed approach exploits a cutting-edge evolutionary strategy to iteratively tweak the coefficients of a linear transformation which can transparently correct raw sensors’ measures thus mitigating the negative effects of the drift. The method learns the optimal correction strategy without the use of models or other hypotheses on the behavior of the physical chemical sensors.  相似文献   
100.
Alkali-free glass as a high energy density dielectric material   总被引:3,自引:0,他引:3  
One of the greatest challenges in the development of new high energy density materials is to increase dielectric permittivity while maintaining high breakdown strength. The dielectric breakdown behavior of an alkali-free barium boroaluminosilicate glass is shown to have remarkably high DC dielectric breakdown strength (12 MV/cm) and reasonably high permittivity (~ 6), equating to energy densities in excess of 35 J/cm3. This behavior is attributed to highly polarizable Ba ions enhancing the real part of complex permittivity, the low loss due to the alkali-free composition, and the substantially defect-free quality of the glass and its surfaces. To our knowledge, this is the highest breakdown strength reported for a bulk glass, and rivals the breakdown strength more typically observed in pristine thin films of SiO2. These findings indicate that alkali-free multicomponent glasses may be strong candidates for next-generation high energy density storage capacitors for portable or pulsed power applications.  相似文献   
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