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41.
牛改     
对于许多国家的普通中产阶级而言,把钱大把大把地砸在改装车上.有点荒唐且不可思议。既便是林宝坚尼(Lambo)、保时捷(Porsche)、玛莎拉蒂(Maserati).或是其他高端车的改装.我们在欣赏它的原装设计的同时,都期望它的改装意念不要过火。车主与改装技师的深入沟通才可以产生经典牛改。  相似文献   
42.
当对汽车施展拳脚准备大干一场时,有些车主朋友比汽车更经受不起折腾。对于Hi-Velocity Motorsports(HVM)的Don Whitmire来说,各式各样的高档车或者SEMA车展的展示样车已经是司空见惯了,然而。他对梅赛德斯一奔驰S600仍赞赏有加。我们的老朋友——汽车改装迷Dennis Scalpi就拥有一辆梅赛德斯-奔驰S600,它是一款高性能的新车型。Dennis Scalpi要求HVM对他的爱车进行音响改装并非一时心血来潮,Whitmire对此也心知肚明。值得一提的是,梅赛德斯-奔驰S600装备了双涡轮增压的顶级v12发动机。排量为5.51,最大功率为368kw  相似文献   
43.
    
Energy usage by mobile robots is becoming a larger concern as autonomous systems increase mission durations. Understanding and characterizing energy usage is key to reliable mission operation. This paper presents a methodology for characterizing energy usage of a ground robot traveling at a constant speed applicable to both open and “black box” (proprietary) platforms. To address testing area limitations, we introduce a “rounded box” path to approximate straight line travel. For a case study, this methodology was applied to an iRobot Packbot on grass and asphalt surfaces. Our results show a decrease in electrical energy used with increasing speed for soft grass and constant energy usage on asphalt. For both surfaces, a similar electrical‐to‐mechanical efficiency curve is obtained.  相似文献   
44.
    
Chemically modified starch was used as resistant starch (RS) to enhance the dietary fibre content in foods. Citrate starch was produced by esterification of starches of various origins and added to toast bread, wafers, pasta and extruded products. The RS content as well as relevant product features were determined and results compared to those of products without any citrate starch addition. The results show that the RS content in toast bread could be increased by approximately 3%, when 7.5% citrate starch was added, compared to non-fortified bread. Changes in product features due to addition of citrate starch could be compensated for by variation in the recipe, such as increasing the amount of water. Thus, appealing products could be obtained with an enriched dietary fibre content. The extend of the RS enhancement depends highly on the food system chosen.  相似文献   
45.
46.
    
All real‐life multiobjective optimization problems (MOPs) are considered dynamic. It is occurring due to fluctuations in environmental or the global market instabilities that lead to the quick fluctuations of prices. Wireless sensor network optimization problem, by nature, is considered one of the dynamic MOP (DMOP) and needs to be solved by a special method to save time and effort. Thus, this paper proposed a novel particle swarm optimization (PSO) for dynamic wireless sensor network MOP to accelerate data transfer in networks and reduce energy losses. Generally, in DMOPs, the optimization period is broken into several equal subperiods. In each subperiod, there is a dynamic parameter that changes. In the proposed approach, PSO is used to handle DMOPs without any changing of its structure and has fast convergence properties. However, a new mechanism to choose the personal and global preferred particles is introduced, which based on the distance between the nondominated solutions obtained so far and the particles positions by using Euclidean metric. In addition, two types of archives are used to maintain the nondominated solutions. The first one is used to store the nondominated solutions obtained by each particle, whereas the second type is used to store the nondominated solutions achieved by all particles. The novel methodology performance is proved by applying it on three benchmark problems that were chosen from the literature and one design problem from the engineering domain. The simulation results mentioned that the proposed algorithm is active and efficacious in solving DMOPs.  相似文献   
47.
    
Pancreatic ductal adenocarcinoma remains an aggressive cancer with a low 5-year survival rate. Although gemcitabine has been a standard treatment for advanced pancreatic cancer, patients often develop resistance to this therapeutic. We have previously shown that treating pancreatic cancer cells in vitro with a combination of gemcitabine and the cytokine TRAIL significantly reduced both cell viability and survival. The data presented here demonstrate that this response to treatment is inhibited when cells are incubated with a conditioned medium derived from untreated cells. We show that this inhibition is specifically mediated by extracellular vesicles present in the conditioned medium, as seen by a significant decrease in apoptosis. Additionally, we further demonstrate that this effect can be reversed in the presence of GW4869, an inhibitor of exosome biogenesis and release. These results show that pancreatic cancer cell-derived extracellular vesicles can confer resistance to treatment with gemcitabine and TRAIL. The implications of these findings suggest that removal of EVs during treatment can improve the response of cells to gemcitabine and TRAIL treatment in vitro.  相似文献   
48.
    
Bacterial membrane vesicles (BMVs) are nanoparticles produced by both Gram-negative and Gram-positive bacteria that can function to modulate immunity in the host. Both outer membrane vesicles (OMVs) and membrane vesicles (MVs), which are released by Gram-negative and Gram-positive bacteria, respectively, contain cargo derived from their parent bacterium, including immune stimulating molecules such as proteins, lipids and nucleic acids. Of these, peptidoglycan (PG) and lipopolysaccharide (LPS) are able to activate host innate immune pattern recognition receptors (PRRs), known as NOD-like receptors (NLRs), such as nucleotide-binding oligomerisation domain-containing protein (NOD) 1, NOD2 and NLRP3. NLR activation is a key driver of inflammation in the host, and BMVs derived from both pathogenic and commensal bacteria have been shown to package PG and LPS in order to modulate the host immune response using NLR-dependent mechanisms. Here, we discuss the packaging of immunostimulatory cargo within OMVs and MVs, their detection by NLRs and the cytokines produced by host cells in response to their detection. Additionally, commensal derived BMVs are thought to shape immunity and contribute to homeostasis in the gut, therefore we also highlight the interactions of commensal derived BMVs with NLRs and their roles in limiting inflammatory diseases.  相似文献   
49.
50.
    
Colorimetric nanofibers provide visual, easy-to-interpret sensors for personal use as well as advanced applications. The potential of 2-n-butyl-2-oxazoline (B) and 2-ethyl-2-oxazoline (E) statistical copolymers as a universal, versatile support platform for nanofibrous halochromic sensor design is demonstrated. These polymers are electrospinnable from eco-friendly solvent systems, while wettability, moist adsorption capacity, and water-solubility of the membranes can be easily tuned by changing the B/E monomer ratio, ensuring wide applicability. The halochromic sensing functionality is introduced by incorporating the alizarin yellow R (AYR) chromophore, which is covalently modified with an ethyl ester-group or a short poly(2-n-butyl-2-oxazoline) chain, which is demonstrated to simultaneously prevent dye-leaching and allows tuning of the halochromic pH-sensing window. The colorimetric nanofibrous sensors reversibly respond toward aqueous solutions of different pH, (hydrochloric) acid and alkaline (ammonia) vapors, and several biogenic amines with detection limits as low as 5 ppb. Tunability of sensor responsivity, sensitivity, and pKa via manipulation of dye–polymer interactions, determined by support polymer structure and semi-crystallinity, as well as the chain length of the AYR-modified polymer, are discussed. Preliminary proof-of-principle studies indicate the potential of the developed sensors for sub-ppm biogenic amine vapor detection, which may serve as the basis for future applications in food packaging or breath analysis.  相似文献   
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