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81.
Listeria monocytogenes (LM) is a major foodborne pathogen causing septicemia, meningitis and death in humans. LM infection is preceded by its attachment to and invasion of human intestinal epithelium followed by systemic spread. The major virulence factors in LM include motility, hemolysin and lecithinase production. Reducing LM attachment to and invasion of host tissue and production of virulence factors could potentially control listeriosis in humans. This study investigated the efficacy of sub-inhibitory concentrations (SICs, concentrations not inhibiting bacterial growth) of three, generally regarded as safe (GRAS)-status, plant-derived antimicrobial compounds in reducing LM attachment to and invasion of human colon adenocarcinoma (Caco-2) and human brain microvascular endothelial cells (HBMEC). Additionally, the effect of these compounds on the aforementioned LM virulence factors was studied. The compounds and their respective SICs used relative to their MICs were trans-cinnamaldehyde (TC 0.50mM, 0.75mM with the MIC of 0.90mM), carvacrol (CR 0.50mM, 0.65mM with the MIC of 0.75mM), and thymol (TY 0.33mM, 0.50mM with the MIC of 0.60mM). All three-plant antimicrobials reduced LM adhesion to and invasion of Caco-2 and HBMEC (p<0.05). The compounds also decreased LM motility, hemolysin production and lecithinase activity (p<0.05). Real-time PCR data revealed that TC, CR, and TY down-regulated the expression of LM virulence genes by >3.0 folds compared to controls (p<0.05). Results suggest that TC, CR, and TY could potentially be used to control LM infection; however, in vivo studies are necessary to validate these results.  相似文献   
82.
With the improved processing power, graphic quality and high-speed wireless connection in recent generations of mobile phones, it looks more attractive than ever to introduce networked games on these devices. However, these games consume higher levels of energy. While device features and application resource requirements are rapidly growing, the battery technologies are not growing at the same pace. Therefore, the main concern is the limitation of the battery power of such portable devices to support potentially long-hour of game play. In this paper we present ARIVU, a scalable power aware middleware that dynamically controls the energy consumption of wireless interface based on the game and system state while maintaining the user experience. The middleware is able to save up to 60% of the total energy consumed by the 802.11 g wireless interfaces for First Person Shooting (FPS) games and up to 35% of the total energy for Massively Multiplayer Online Role Playing Games (MMORPG).  相似文献   
83.
The effect of fish oil recovered from fish visceral waste (FVW-FO) on serum and liver lipids, activity of HMG-CoA reductase in liver microsomes and EPA + DHA incorporation in liver, heart and brain were evaluated. Rats were fed different concentrations of FVW-FO providing 1.25%, 2.50%, 5.0% EPA + DHA recovered by either fermentation or enzymatic hydrolysis for 8 weeks. Feeding FVW-FO reduce triacylglycerols (5.96–20.3%), total cholesterol (7.9–21.5%) and LDL (7.39–21.7%) cholesterol levels in serum compared to group fed on a control diet (groundnut oil). The activity of HMG-CoA reductase was reduced (p < 0.05) in the FVW-FO fed groups compared to the control. EPA + DHA level in serum, liver, brain and heart increased with increments in dietary EPA + DHA. Results show the hypolipidemic property of FVW-FO and reduced HMG-CoA reductase activity which is proportional to the incorporation of EPA + DHA. Recovery of FVW-FO will address the increasing demand for fish oil and reduce pollution problems.  相似文献   
84.
Magnetic flux leakage technique is used for defect detection inside a magnetically permeable bar by measuring the leakage fields outside the bar. Defects of varying sizes in a magnetically permeable bar have been modelled as localized anti-dipoles with different moments. These defect locations and moments have to be determined based on the measurement of the leakage fields in the presence of random noise. Multiple Signal Classification (MUSIC) approach has been used to identify the defect locations and the moments of these defects. After finding the location of the first dipole representing the larger defect, using orthogonal projection of the measured magnetic field data away from the first defect location, location of the next dipole is identified by MUSIC. This process is continued until all the defects are exhausted. The leakage fields from three deeply buried defects were simulated by direct forward calculation and the resulting data were utilized for inversion using this approach. It has been possible to identify the number of defects and their locations by this approach even in the presence of reasonable levels of additive noise.  相似文献   
85.
The non-orthogonal multiple access (NOMA) wireless networks are a robust multi-access mechanism that serves multiple clients accessing the same resource block simultaneously. The fifth-generation wireless networks offer huge efficiency in spectrum utilization, which can be exploited to deploy NOMA for LOS communication of unmanned aerial vehicles (UAVs). Previous research has extensively analyzed various aspects of NOMA-UAV communication systems, including user access fairness, coverage, maximizing system capacity, and total energy efficiency. However, only a few researchers have focused on maximizing the EE of NOMA-UAV wireless networks with user quality of service (QoS) constraints. This paper proposes a fuzzy logic-based crossover-based coati optimization algorithm for maximizing the energy efficiency of NOMA-UAV, along with user scheduling. The main objective of this model is to offer a solution to the joint energy efficiency and user QoS scheduling problem. The fuzzy decision-making strategy optimizes the energy efficiency (EE) of NOMA-UAV by selecting appropriate power and time resources. Additionally, the crossover-based coati optimization algorithm transforms the subchannel allocation problem into a two-sided matching procedure. The efficiency of the proposed algorithm is evaluated concerning overall residual energy, number of remaining nodes, and time consumption. The experimental outcomes demonstrate the capability of the proposed model in optimizing the energy efficiency of the NOMA-UAV network by identifying the optimal resource set in terms of time and power while satisfying the clients' QoS.  相似文献   
86.
The discovery of metabolically active brown adipose tissue (BAT) in human adults and the worldwide increase in obesity and obesity-related chronic noncommunicable diseases (NCDs) has made BAT a therapeutic target in the last two decades. The potential of BAT to oxidize fatty acids rapidly and increase energy expenditure inversely correlates with adiposity, insulin and glucose resistance, and cardiovascular and metabolic diseases. Currently, BAT is recognized by a new molecular signature; several BAT-derived molecules that act positively on target tissues have been identified and collectively called batokines. Bioactive compounds present in foods are endowed with thermogenic properties that increase BAT activation signaling. Understanding the mechanisms that lead to BAT activation and the batokines secreted by it within the thermogenic state is fundamental for its recruitment and management of obesity and NCDs. This review contributes to recent updates on the morphophysiology of BAT, its endocrine role in obesity, and the main bioactive compounds present in foods involved in classical and nonclassical thermogenic pathways activation.  相似文献   
87.

Nowadays, the Wire Electrical Discharge Machining (WEDM) process was also working to cut the hard titanium alloys. During the WEDM, the generation of high temperatures was used to melt and vaporize and also flushed away the hard titanium alloy. The tough Ti–6Al–2Sn–4Zr–2Mo alloy was machined in the current research by the WEDM method and machining features such as surface roughness (SR) and Material Removal Rate (MRR) were statistically evaluated to achieve optimum performance. The investigations were performed using the Taguchi orthogonal array technique. The optimum process factors were defined from the main effect plot 32 μs, 3 m/min, and 12 g for material removal rate and as 10 μs, 32 μs, 7 m/min, and 12 g for surface roughness. The best essential parameters were established from the Analysis of variance (ANOVA) analysis. The pulse on-time current and pulse off time were identified as important parameters for the material removal rate with a contribution of 23.60%, 5.91%, and 65.02%. The best essential parameters for surface roughness were pulse on time, pulse off time, and a combination of pulse on-time and pulse off time with a percentage contribution of 22.71% and 36.88% respectively.Moreover, the machined surface was examined using the Scanning Electron Microscope (SEM).

  相似文献   
88.
The thermal diffusivity of chemically vapour deposited silicon carbide reinforced with either Nicalon SiC yarn or PAN-precursor carbon fibres was measured by the laser-flash method during various time-temperature treatments. The diffusivity was found to depend on the degree of densification, the direction of heat flow with respect to the fibre orientation, and the thermal history. Structural modifications, confirmed by X-ray diffraction, produced large permanent changes in the thermal properties of the SiC-SiC composites when heated above 1200° C, while only minor changes were seen in C-SiC composites heated above 1500° C. On sabbatical leave of absence from the Société Européenne de Propulsion, Bordeaux, France.  相似文献   
89.
There are many different types of word processor on the market today, each storing documents in a different way. Hence, a document created using one particular word processor cannot be edited using another word processor. Documents are often exchanged in an office environment, and should be in a form acceptable by other vendors' word processing packages. To make the exchange of documents created using word processors general and flexible, a standard canonical form has been adopted, and is outlined here. A methodology for converting the word processor documents into canonical form is described, detailing document and canonical structure, look-up tables, the intermediate file structure, and logical/layout object information. The author concludes by working through the methodology using an example.  相似文献   
90.
A PCR method for uniform amplification of a mixture of DNA templates differing in GC content is described using the two enzyme approach (Klentaq1 and Pfu DNA polymerase) and a combination of DMSO and betaine. This method was applied to amplify the CGG repeat region from the fragile X region.  相似文献   
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