Mobile social networks are among subsets of delay tolerant networks. The nodes of these networks are mobile and the communication between them is done wireless and all nodes have social characteristics. The connection between these nodes is temporary and there is not end to end route between the source and the destination. Therefore, it is difficult to deliver the packets to the destination. One of the best routing methods in such networks is to use the information about the network context. These methods require the process of information collection and replicate the packets based on the context to increase the delivery ratio and enforce great overhead onto the network. Since the nodes have social characteristics and these features exist within the network, it seems that using them within the routing can be useful. In this paper a community based method of delivering is proposed that uses social characteristics of the individual members for routing the packets. Using the predetermined roles for the members that do not need data collection level can improve routing in these networks. In this method a tree is formed and each group of the members is entitled in one branch of it. The transmission of the packets from the source to the destination is done based on the differences between their characteristics and through the route which has the highest number of the nodes. The simulation results show that the delivery ratio of this method has increased regarding the related works and the overhead ratio has decreased.
Two superparamagnetic and heat resistant xanthene based poly(ether-imide) nanocomposites were successfully synthesized. Field emission scanning electron microscopy, transmission electron microscope, X-ray diffraction, thermal gravimetric analysis, vibrating sample magnetometer, Energy-dispersive X-ray spectroscopy and Fourier-transform infrared (FTIR) techniques were used for studying the morphology, crystalline phase, thermal stability and magnetization properties of the nanocomposites. The neat form of the corresponding poly(ether-imide) was also prepared by thermal imidization method and its structure was confirmed by FTIR, proton nuclear magnetic resonance (1H NMR), UV–Vis and photoluminescence (PL) spectroscopies. In order to investigate the effects of modifying the surface of Fe3O4 nanoparticles on thermal properties of the nanocomposites, the surface of Fe3O4 nanoparticles was coated with SiO2 and polysuccinimide (PSI), sequentially. Then, both the unmodified Fe3O4 and surface-modified Fe3O4 (Fe3O4@SiO2–PSI) nanoparticles were used as fillers for the polymer matrix. According to the results, the prepared nanocomposites were superparamagnetic and showed higher thermal stability in comparison to the neat poly(ether-imide). Furthermore, poly(ether-imide)/Fe3O4@SiO2–PSI (PIEN 10b) nanocomposite showed higher thermal stability and dispersed better in the polymer matrix [in comparison to poly(ether-imide)/Fe3O4 (PIEN 10 a)] due to the presence of imide groups and high hydroxyl content of the functional Fe3O4 nanoparticles which caused high interactions between poly(ether-imide) and functional Fe3O4. Furthermore, the presence of methyl, ether and bulky xanthene groups in the poly(ether-imide(backbone improved the solubility of the neat polymer in organic solvents. These properties can be very helpful for extending new applications of poly(ether-imide)s. 相似文献
Impaired wound healing in people with diabetes has multifactorial causes, with insufficient neovascularization being one of the most important. Hypoxia-inducible factor-1 (HIF-1) plays a central role in the hypoxia-induced response by activating angiogenesis factors. As its activity is under precise regulatory control of prolyl-hydroxylase domain 2 (PHD-2), downregulation of PHD-2 by small interfering RNA (siRNA) could stabilize HIF-1α and, therefore, upregulate the expression of pro-angiogenic factors as well. Intracellular delivery of siRNA can be achieved with nanocarriers that must fulfill several requirements, including high stability, low toxicity, and high transfection efficiency. Here, we designed and compared the performance of layer-by-layer self-assembled siRNA-loaded gold nanoparticles with two different outer layers—Chitosan (AuNP@CS) and Poly L-arginine (AuNP@PLA). Although both formulations have exactly the same core, we find that a PLA outer layer improves the endosomal escape of siRNA, and therefore, transfection efficiency, after endocytic uptake in NIH-3T3 cells. Furthermore, we found that endosomal escape of AuNP@PLA could be improved further when cells were additionally treated with desloratadine, thus outperforming commercial reagents such as Lipofectamine® and jetPRIME®. AuNP@PLA in combination with desloratadine was proven to induce PHD-2 silencing in fibroblasts, allowing upregulation of pro-angiogenic pathways. This finding in an in vitro context constitutes a first step towards improving diabetic wound healing with siRNA therapy. 相似文献
The aim of this study was to investigate the content of omega-3 fatty acids in Persian Gulf fishes. The fishes were collected from Persian Gulf and the content of fatty acids in the head, muscle, and liver of fishes were determined. Quantitative analysis of fatty acids was performed by gas chromatography (GC) and methylmyristate was used as the reference material. GC and mass spectrometer (GC- mass) was applied for qualitative analysis and cod liver oil with all of omega-3 fatty acids was used as standard. Ghezel ala, Zamin kan-e-dom navari and Sorkhu mahi had maximum levels of omega-3 in total body. Halva Sefid, Gish-e-deraz baleh and Shamshiri were poor sources of omega-3. The liver of fish had the most content of omega-3 fatty acids followed by muscle and head, respectively. 相似文献
AbstractSeveral studies have been conducted on the effects of peanut consumption on cardiovascular diseases (CVD) risk factors. However, the findings are conflicting and appear inconsistent. The aim of this review is to summarize the findings on the effect of peanut consumption on the risk factors of CVDs. We used relevant keywords and searched through PubMed, Scopus and Web of Science for articles published studies up to November 2018. Randomized controlled trials (RCTs) were included in this meta-analysis. Random or fixed-effects meta-analysis method depending on the results of heterogeneity tests was used to estimate the effect size. Between-study heterogeneity was assessed by Q test and I2 index. Subgroup analysis was conducted to find any excess relationship. Publication bias was checked by Egger’s test and funnel plot. Quality of studies was assessed by the Cochrane criteria. According to the results of 13 RCTs, peanuts has no significant effect on weight (WMD: ?0.11?kg, P?=?0.773), waist circumference (WMD: ?1.41?cm, P?=?0.139), body mass index (WMD: ?0.14?kg/m2, P?=?0.428), systolic and diastolic blood pressure (WMD: ?0.09?mmHg, P?=?0.939 and WMD: 0.60?mmHg, P?=?0.652, respectively), low-density lipoprotein cholesterol (WMD: ?3.31?mg/dl, P?=?0.472), triglyceride (WMD: ?7.59?mg/dl, P?=?0.180), total cholesterol (WMD: 3.15?mg/dl, P?=?0.171), fasting blood sugar (WMD: 0.57?mg/dl, P?=?0.604) and serum insulin (WMD: ?0.40, P?=?0.582). Also, this meta-analysis showed that peanut had a positive significant effect on high-density lipoprotein cholesterol (HDL) (WMD: 2.72?mg/dl, P?=?0.001). Peanuts consumption has a positive significant effect on HDL especially at the type of peanut oil, high-oleic peanut and peanut sprout and in healthy subjects and for consumption more than 12?weeks, while has no significant effect on other CVD risk factors. 相似文献
Multimedia Tools and Applications - In recent years, measuring the speed of vehicles by a single camera has been done using several methods including the road geometric information, the difference... 相似文献
The ratios of gas flow to steam flow are huge in heat recovery steam generators (HRSGs) compared to other steam generators. So the volume which is occupied by components of the HRSG such as economizer, evaporator and superheater is important factor when the HRSG is applied in structures including buildings and ships. The optimum volume of a HRSG is deduced through optimization of entropy generation and cost evaluation. By increasing volume, second law of thermodynamics is improved, but this improvement may not be economical. In this work, the best dimensions and arrangements of flows in HRSG are obtained by constructal design and the optimization method is algorithm genetic. In this case, super heater temperature, pinch point, water/steam flow rate and gas pressure drop are derived from configuration which designed by constructal theory for HRSG. The effects of gas flow rate and inlet gas temperature are examined on the values of optimum volume. 相似文献
This paper addresses a bi-modal multi-objective discrete urban road network design problem with automobile and bus flow interaction. The problem considers the concurrent urban road and bus network design in which the authorities play a major role in designing bus network topology. The road network design deals with the decision making for new street constructions, lane additions to existing streets, lane allocations for two-way streets, and the orientations and locations of one-way streets. The bus network design is performed by keeping the terminal stations of the existing bus lines unchanged and redesigning the forth and back routes of each line. Four measures, namely user benefit, the demand coverage of the bus network, the demand share of the bus mode, and the average travel generalized cost of bus passengers, are used to evaluate the network design scenarios. The problem is formulated as a multi-objective optimization model in which a modal-split/assignment model is included to depict the mode and route choice behaviors of travelers. The model is solved by the hybrid genetic algorithm and the hybrid clonal selection algorithm. The performance of these algorithms is presented and investigated by solving a number of test networks. 相似文献