53 research outputs found
Studying effects of gold nanoparticle on dose enhancement in megavoltage radiation
Background: Gold nanoparticles are emerging as promising agents for cancer therapy and are being investigated as drug carriers, photothermal agents, contrast agents and radiosensitisers. Objective: The aim of this study is to understand characteristics of secondary electrons generated from interaction of gold nanoparticles GNPs with x-rays as a function of nanoparticle size and beam energy and thereby further understanding of GNPenhanced radiotherapy. Methods: Effective range, defection angle, dose deposition, energy, and interaction processes of electrons produced from the interaction of x-rays with a GNP were calculated by Monte Carlo simulations. The MCNPX code was used to simulate and track electrons generated from 30 and 50 nm diameter GNP when it is irradiated with a cobalt-60 and 6MV photon and electron beam in water. Results: When a GNP was present, depending on beam types used, secondary electron production increased by 10- to 2000-fold compared to absence of a GNP. Conclusion: GNPs with larger diameters also contributed to more doses. © 2015, Shiraz University of Medical Sciences. All rights reserved
Studying the factors affecting urban dispersion in mashhad metropolis
In recent decades, urban population in the world, especially in southern countries, hasexceeded rural population that has brought about urban land expansion followed bydispersion phenomenon, the result of which has created problems in environmental,economic, social, and physical aspects including increased air pollution, potentialdeterioration within the city, and destruction of farms and open spaces. The aim of thisstudy is to investigate the roots of dispersion in Mashhad metropolis in order to identifysolutions to control this problem. The tools used in this research were GIS software formapping, quantitative methods of Holdren Model, urban primacy index, and area topopulation growth rate for review and analysis, and at first by examining area topopulation growth rate, Mashhad- developmental process map, Holdren model, andgross population-density dispersion model of this city was shown.Then the roots of dispersion including market failure (checking the price of land), technology, natural population-growth process, and migration were analyzed. To study the dispersion in Mashhad metropolis, Holdren model was used, according to which only 34% of dispersion is population growth, and 66% of urban growth is related to horizontal growth. This is indicative of the dispersion in Mashhad metropolis, and the most important reasons are low price of housing in the suburb, ignoring social costs arising from it, increasing percentage of car ownership, gradual population growth inMashhad due to political priority, and the concentration of facilities in it that are thereason of increase in immigration to this metropolis. To deal with this phenomenondispersion, it is proposed that patterns of sustainable development such as transportbased development and compact city are used.Key words: urban dispersion, technology, roots of Mashhad dispersion, the price ofland, immigratio
Effects of Gas Cross-over through the Membrane on Water Management in the Cathode and Anode Sides of PEM Fuel Cell
Water management in a proton exchange membrane fuel cell (PEMFC) is numerically modeled by considering the 2D, non-isothermal steady flow assumptions. Governing equations are solved in all cell layers including cathode and anode electrodes by finite volume method using a single-region approach. The effect of gas cross-over through the membrane is studied on cell performance. This consideration, not only improves the general accuracy of modeling but also makes it possible to model energy losses due to direct reaction of reactant gases. The effect of some key variables such as liquid water diffusivity, current density, membrane thickness, etc. on PEMFC conditions such as the amount of saturated liquid water, power density, cell temperature, cross-over efficiency and so on are examined. It was observed that the amount of saturated liquid water on the anode side is considerably important. This observation addresses needs for further investigation of liquid water behavior in the anode electrode. The amount of liquid water saturation in both the cathode and anode electrodes is increased with increasing the current density. The results showed that at the current density of 0.2 A/cm2, cross-over effect causes about 10% reduction in cell efficiency and by decreasing the current density this effect is enhanced
Safety and Efficacy of MLC601 in Iranian Patients after Stroke: A Double-Blind, Placebo-Controlled Clinical Trial
Objective. To investigate the safety and efficacy of MLC601 (NeuroAid) as a traditional Chinese medicine on motor recovery after ischemic stroke. Methods. This study was a double-blind, placebo-controlled clinical trial on 150 patients with a recent (less than 3 month) ischemic stroke. All patients were given either MLC601 (100 patients) or placebo (50 patients), 4 capsules 3 times a day, as an add-on to standard stroke treatment for 3 months. Results. Sex, age, elapsed time from stroke onset, and risk factors in the treatment group were not significantly different from placebo group at baseline (P > .05). Repeated measures analysis showed that Fugl-Meyer assessment was significantly higher in the treatment group during 12 weeks after stroke (P < .001). Good tolerability to treatment was shown, and adverse events were mild and transient. Conclusion. MLC601 showed better motor recovery than placebo and was safe on top of standard ischemic stroke medications especially in the severe and moderate cases
CGMP: cloud-assisted green multimedia processing
With continued advancements of mobile computing and communications, emerging novel multimedia services and applications have attracted lots of attention and been developed for mobile users, such as mobile social network, mobile cloud medical treatment, mobile cloud game. However, because of limited resources on mobile terminals, it is of great challenge to improve the energy efficiency of multimedia services. In this paper, we propose a cloud-assisted green multimedia processing architecture (CGMP) based on mobile cloud computing. Specifically, the tasks of multimedia processing with energy-extensive consumption can be offloaded to the cloud, and the face recognition algorithm with improved principal component analysis and nearest neighbor classifier is realized on CGMP based cloud platform. Experimental results show that the proposed scheme can effectively save the energy consumption of the equipment
Energy-Efficient Service-Oriented Architecture for Mobile Cloud Handover
Mobile cloud computing uses features to deliver outsourcing data to remotely available mobile devices. However, the flexible nature of the mobile device is a critical challenge for the mobile cloud computing environment. The mobile phone significantly degrades the data transfer performance when initiating the handover process. Thus, an energy-efficient handover process could improve the quality of service (QoS). Here, we introduce a secure energy-efficient and quality-of-service architecture (EEQoSA) for the handover process in the mobile cloud computing environment. The proposed architecture involves four layers: application, the Internet protocol multimedia subsystem (IPMS), communication, and media with connectivity layers. These four layers collectively handle the energy-efficiency, security and QoS parameters. Existing service-oriented architectures designed for mobile cloud computing are based on the symmetric encryption cryptography to support different media services. However, this approach easily allows an adversary to expose the symmetric key and gain access to private data. Thus, our proposed architecture uses the secure and strong authentication (SSA) process at the IPMS layer by protecting the media services from unauthorized users, as the IPMS is the central layer that could be the entry point for an adversary. Furthermore, to extend the mobile lifetime during the handover process, an energy detection (ED) model is deployed at the communication layer to detect the energy level of the mobile device prior to the handover initialization process. The media with the connectivity layer supports the secure handover process using a priority enforcement module that allows only legitimate users to complete the re-registration process after initiating the handover. Finally, the architecture is tested using the CloudSim simulation environment and validated by a comparison with other known service-oriented architectures.https://doi.org/10.1186/s13677-017-0079-
Rhizosphere Effect of Kharif Crops on Phosphatases and Dehydrogenase Activities in a Typic Haplustert
Towards Efficient and Scalable Data-Intensive Content Delivery: State-of-the-Art, Issues and Challenges
This chapter presents the authors’ work for the Case Study entitled “Delivering Social Media with Scalability” within the framework of High-Performance Modelling and Simulation for Big Data Applications (cHiPSet) COST Action 1406. We identify some core research areas and give an outline of the publications we came up within the framework of the aforementioned action. The ease of user content generation within social media platforms, e.g. check-in information, multimedia data, etc., along with the proliferation of Global Positioning System (GPS)-enabled, always-connected capture devices lead to data streams of unprecedented amount and a radical change in information sharing. Social data streams raise a variety of practical challenges: derivation of real-time meaningful insights from effectively gathered social information, a paradigm shift for content distribution with the leverage of contextual data associated with user preferences, geographical characteristics and devices in general, etc. In this article we present the methodology we followed, the results of our work and the outline of a comprehensive survey, that depicts the state-of-the-art situation and organizes challenges concerning social media streams and the infrastructure of the data centers supporting the efficient access to data streams in terms of content distribution, data diffusion, data replication, energy efficiency and network infrastructure. The challenges of enabling better provisioning of social media data have been identified and they were based on the context of users accessing these resources. The existing literature has been systematized and the main research points and industrial efforts in the area were identified and analyzed. In our works, in the framework of the Action, we came up with potential solutions addressing the problems of the area and described how these fit in the general ecosystem
EFFECTS OF 6-MONTHS TREATMENT WITH DONEPEZIL AND RIVASTIGMIN ON RESULTS OF NEUROPSYCHOLOGICAL TESTS OF MMSE, NPI, CLOCK AND BENDER IN PATIENTS WITH ALZHEIMER'S DISEASE
Alzheimer's disease is the most common degenerative disease of brain. Nowadays, the most common treatment being used to slow down disease progression, include Donepezil , Rivastigmine and Galantamine, which all of them act as inhibitors of acetyl cholinesterase. General purpose of our study was to show effects of treatment with Donepezil and Rivastigmine, as two drugs that commonly used for treatment of AD in Iran and to compare these effects between two drugs. Samples selected from patients who had Alzheimer` disease with DSM IV criteria and were candidate of receiving Donepezil or Rivastigmine, as treatment of AD, for the first time. We used four neuropsychological tests including MMSE, NPI, Clock and Bender to assess patient's cognitive and behavioral changes during treatment with two drugs. Patients divided to two groups (each group 35 cases); Patients with plan of taking Donepezil entered into one of the groups and patients with plan of taking Rivastigmine entered into another. The four tests were completed once before starting treatment and then, 1 month, 3 months and 6 months after treatment with Donepezil and Rivastigmine. MMSE, 6 months after treatment with Donepezil, improved from 20.63 before treatment to 21.83, which is statistically significant (P = 0.04). Also, MMSE, 6 months after treatment with Rivastigmine, improved from 20.03 before treatment to 22.71, which was statistically significant (P = 0.007). About Clock test, there was a significant improvement from 5.74 before treatment to 6.4 after 6 months of treatment with Rivastigmine; while this significant improvement was not seen in patients receiving Donepezil. In two other tests, no significant differences were seen before and after treatment. Also, No significant difference was detected between two groups and so no different effects on these tests between Donepezil and Rivastigmine in 6 months period of treatment
Large eddy simulation of the flameless oxidation in the IFRF furnace with varying inlet conditions
In the present study, large eddy simulation methodology is applied to investigate the 3D non-premixed flameless oxidation in the IFRF furnace. In order to serve this purpose, to model the combustion and radiation, the partially stirred reactor and finite volume discrete ordinate model are used, respectively.Moreover, the detailed mechanism of GRI-2.11 is undertaken to represent chemistry reactions. The present simulations agree qualitatively well with published experimental data. Finally, the present study focusses on the assessment of the effects of variations in the fuel vertical injection by adding an inert gas as well as the fuel temperature on combustion behavior. The results revealed that important changes occur in the characteristics of the flameless oxidation process
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