452 research outputs found
A genre analysis of Iranian hotel homepages / Faranak Bastami Awal
No full textThe present research is a genre analysis of hotel websites, targeting the main three aspects; the move structure, communicative purposes, and linguistic features on the 23 five-star and four-star hotel homepages in Iran. Bhatia’s (1993) model is used to investigate the communicative purposes of the digital genre, Suen (2013) framework which is a comprehensive model was adapted to examine the rhetorical move structure, and a combination of Bhatia’s (1993) and Cook’s (2001) model was used to analyze the common linguistic features.
The findings of this research are going to contribute some knowledge to the production of more effective homepages specifically for the hotel industry, especially for Iranian hotels’ websites. The main purpose of the hotel homepage is to attract the readers' attention so that the customers are persuaded to buy the products and services. The persuasion is done indirectly by arranging the move structure wisely and the word and grammatical choices correctly to accomplish the hotels' communicative purposes.
This present study can also be used as a guideline for teachers who teach Business English. This study can help students to improve their communicative abilities with regards to promotional and persuasive writing in the Business context.
The present study does not deal with all the issues in this field, but it solely concentrates on the three parts which are to investigate the function and application of communicative purposes, the move structure, and the linguistic features of hotel homepages. Genre analysis of hotel homepages in Iran can be explored in other aspects of the genre analysis field and more extensively for further studies in the future
Naked-eye detection of morphine by Au@Ag nanoparticles-based colorimetric chemosensors
No full textIn this study, we report a novel and facile colorimetric assay based on silver citrate-coated Au@Ag nanoparticles (Au@AgNPs) as a chemosensor for the naked-eye detection of morphine (MOR). The developed optical sensing approach relied on the aggregation of Au@Ag NPs upon exposure to morphine, which led to an evident color variation from light-yellow to brown. Au@Ag NPs have been prepared by two different protocols, using high- and low-power ultrasonic irradiation. The sonochemical method was essential for the sensing properties of the resulting nanoparticles. This facile sensing method has several advantages including excellent stability, selectivity, prompt detection, and cost-effectiveness
Expression pattern of miR-193a, miR122, miR155, miR-15a, and miR146a in peripheral blood mononuclear cells of children with obesity and their relation to some metabolic and inflammatory biomarkers
No full textBackgroundThe widespread presence of childhood obesity has increased considerably over three decades. The present study was designed to investigate expression patterns of miR-146a, miR-155, miR-15a, miR-193a, and miR-122 in peripheral blood mononuclear cells (PBMCs) in children who are obese along with their association with metabolic and inflammatory biomarkers.MethodsNinety test subjects were admitted. The profile of blood pressure, resting energy expenditure (REE), anthropometric measures, body composition, dietary intakes, physical activity levels, insulin, and lipid profile, fasting blood glucose (FBG), high-sensitivity C-reactive protein (hs-CRP), and pubertal stage have been measured. Total RNA (including small RNAs) was extracted from PBMCs. The expression levels of miRNAs were measured by stem-loop RT-qPCR.ResultsThe miR-155a expression level was significantly lower in obese children, children with high hs-CRP, and children with high-fat mass. Obese girls had significantly higher PBMC levels of miR-122. MiR-155a had a significant negative association with fasting insulin, HOMA-IR, and hs-CRP. There were significant positive associations between miR-193a and miR-122 expression levels and fasting insulin, HOMA-IR, and TG. MiR-15a was positively correlated with fasting insulin and HOMA-IR. Children with metabolic syndrome, insulin resistance, and high-fat mass had higher PBMC levels of miR-122 and miR-193a. Higher miR-193a and miR-122 levels were also detected in PBMCs of children with fast REE, compared to those with slow REE, and the subjects with high hs-CRP, respectively.Conclusionlower level of miR-155 expression in obese subjects and significant associations unfolds the need for more studies to detect the possible underlying mechanisms
Cooperative secure transmission relying on the optimal power allocation in the presence of untrusted relays, a passive eavesdropper and hardware impairments
No full textIn this work, by considering a variety of realistic hardware impairments, we aim to enhance the security of a cooperative relaying network, where a source intends to transmit its confidential information to a destination in the presence of a group of untrusted amplify-and-forward relays, as potential eavesdroppers (Eves), and an entirely passive multiple-antenna aided Eve. Our goal is to safeguard the information against these two types of eavesdropping attacks, while simultaneously relying on the untrusted relays to boost both the security and reliability of the network. To reach this goal, we propose a novel joint cooperative beamforming, jamming and power allocation policy to safeguard the confidential information while concurrently achieving the required quality-of-service at the destination. We also take into account both the total power budget constraint and a practical individual power constraint for each node. Our optimization problem can be split into two consecutive sub-problems. In the first sub-problem, we are faced with a non-convex problem which can be transformed into the powerful difference of convex (DC) program. A low-complexity iterative algorithm is proposed to solve the DC program, which relies on the constrained concave-convex procedure (CCCP). We further introduce a novel initialization method, which is based on a feasible point of the original problem obtained from a novel iterative feasibility search procedure, rather than an arbitrary (infeasible) point as in the conventional CCCP. The second sub-problem of our optimization problem is a convex optimization problem and can be solved efficiently adopting the classic interior point method. The numerical results provided illustrate that although the trusted relaying scenario outperforms the untrusted relaying for small and medium total power budgets, however, by increasing the total power budget, the secrecy performances of both the trusted and untrusted relaying converge to the same. Additionally, by equally sharing the total impairments at the relays between the transmitter and the receiver the best secrecy performance is presented
Influences of spinel type and polymeric surfactants on the size evolution of colloidal magnetic nanocrystals (MFe(2)O(4), M= Fe, Mn)
No full textTwo types of polymeric surfactants, PEG₃₀₀₀ and PVP₄₀₀₀₀, were used for the preparation of magnetic ferrite MFe₂O₄ (M = Mn, Fe) colloidal nanocrystals using a solvothermal reaction method. The effect of spinel type effect on the size evolution of various nanoparticles was investigated. It was found that Fe₃O₄ nanoparticles exhibited higher crystalinity and size evolution than MnFe₂O₄ nanoparticles with use of the two surfactants. It is proposed that this observation is due to fewer tendencies of surfactants on the surface of Fe₃O₄ building blocks nanoparticles than MnFe₂O₄. Less amounts of surfactant or capping agent on the surface of nanoparticles lead to the higher crystalibity and larger size. It is also suggested that the type of spinel (normal or inverted spinel) plays a key role on the affinity of the polymeric surfactant on the surface of building blocks.Tahereh R. Bastami, Mohammad H. Entezari, Chiwai Kwong, Shizhang Qia
Maximizing the secrecy energy efficiency of the cooperative rate-splitting aided downlink in multi-carrier UAV networks
No full textAlthough Unmanned Aerial Vehicles (UAVs) are capable of significantly improving the information security by detecting the eavesdropper's location, their limited energy motivates our research to propose a secure and energy efficient scheme. Thanks to the common-message philosophy introduced by Rate-Splitting (RS), we no longer have to allocate a portion of the transmit power to radiate Artificial Noise (AN), and yet both the Energy Efficiency (EE) and secrecy can be improved. Hence we define and study the Secrecy Energy Efficiency (SEE) of a multi-carrier multi-UAV network, in which Cooperative Rate-Splitting (CRS) is employed by each multi-antenna UAV Base-Station (UAV-BS) for protecting their downlink transmissions against an external eavesdropper (Eve). Furthermore, we consider the challenging scenario in which CRS is employed by each multi-antenna UAV-BS to protect their corresponding downlink transmissions against an external Eve. We further consider a difficult scenario in terms of security in which only imperfect channel state information of Eve is available at the Tx. Accordingly, we conceive a robust secure resource allocation algorithm, which maximizes the SEE by jointly optimizing both the user association matrix and the network parameter allocation problem, including the RS precoders, time slot sharing and power allocation. Due to the non-convexity of the problem, it is decoupled into a pair of convex sub-problems. Firstly, new two-tier intra-cell optimization problems are formulated for achieving ξ-optimal solutions by iterative block coordinate decent programming. Then, the power of each sub-channel is optimized by formulating the associated power control problem. Simulation results confirm that the scheme conceived enhances both the secrecy and energy efficiency of the system compared to the existing cooperative non-orthogonal benchmarks
Supplymentary_data – Supplemental material for A link between expression level of long-non-coding RNA <i><b>ZFAS1</b></i> in breast tissue of healthy women and obesity
No full textSupplemental material, Supplymentary_data for A link between expression level of long-non-coding RNA ZFAS1 in breast tissue of healthy women and obesity by Yaser Mansoori, Mohammad Bagher Tabei, Alireza Askari, Pantea Izadi, Abdolreza Daraei, Mohammad Mehdi Naghizadeh, Zahra Zendehbad, Milad Bastami, Ziba Nariman-Saleh-Fam, Hosein Mansoori and Javad Tavakkoly-Bazzaz in The International Journal of Biological Markers</p
Discriminative detection of morphine and methamphetamine-like street samples by label-free Cu doped-silver nanoparticles chemosensor
No full textThis research provides a straightforward and sensitive method for detecting morphine (MOR) and methamphetamine (MET) by colorimetry. In order to characterize the nanoprobe as it was prepared, XRD, FT-IR, XPS, UV–vis, TEM, ICP, DLS, and EDS analyses were conducted. We evaluated the performance of Ag/Cu nanoparticles for colorimetric sensing of MOR and MET. As well as naked-eye detection (photographs), UV–visible spectroscopy was used to monitor and record the results. Color shifts of colloidal NP solutions or surface plasmon resonance (SPR) absorbance bands were used to differentiate between MOR and MET, leading to the discovery that NP could distinguish between the two. Based on the linearity of the calibration curves' ranges, MOR and MET were found to have different limits of detection (LODs), which are 0.21 μg/mL and 0.49 μg/mL for each, respectively. In addition, they displayed a linear range of 0–50 μg/mL and 0–100 μg/mL, for MOR and MET, respectively. When Ag/Cu NPs are exposed to MOR and MET, they aggregate and exhibit noticeable color changes. For MOR, the changes ranged from bright yellow to smoky, while for MET, they were dark orange. The optimal incubation time for sensing MOR and MET was 7 and 35 min, respectively
Large-scale rate-splitting multiple access in uplink UAV networks: effective secrecy throughput maximization under limited feedback channel
No full textUnmanned aerial vehicles (UAVs) are capable of improving the performance of next generation wireless systems. However, their communication performance is prone to both channel estimation errors and potential eavesdropping. Hence, we investigate the effective network secrecy throughput (ENST) of the uplink UAV network, in which rate-splitting multiple access (RSMA) is employed by each legitimate user for secure transmission under the scenario of massive access. To maximize the ENST, the transmission rate versus power allocation relationship is formulated as a max-min optimization problem, relying on realistic imperfect channel state information (CSI) of both the legitimate users and passive eavesdroppers (Eves). In the model considered, each user transmits a superposition of two messages to a UAV base-stations (UAV-BS), each having different transmit power and the UAV-BS adopts a successive interference cancellation (SIC) technique to decode the received messages. Given the non-convexity of the problem, it is decoupled into a pair of sub-problems. In particular, we derive a closed form expression for the optimal rate-splitting fraction of each user. Then, given the optimal rate-splitting fraction of each user, the \epsilon-constrainted transmit power of each user is calculated by harnessing sequential parametric convex approximation (SPCA) programming. Our simulation results confirm that the scheme conceived significantly improves the ENST compared to both the existing orthogonal and non-orthogonal benchmarks.</p
Optimization of waterflooding performance in a layered reservoir using a combination of capacitance-resistive model and genetic algorithm method
No full textManaging oil production from reservoirs to maximize the future economic return of the asset is an important issue in petroleum engineering. In many applications in reservoir modeling and management, there is a need for rapid estimation of large-scale reservoirs. The capacitance-resistive model (CRM), regarded as a promising rapid evaluator of reservoir performance, has recently been used for simulation of single-layer reservoirs. Injection and production rates are considered as input and output signals in this model. Connections between the wells and the effects of injection rates on production rates are calculated based on these signals to develop a simple model for the reservoir. In this study, CRM is improved to model a multilayer reservoir and is applied to estimate and optimize waterflooding performance in an Iranian layered reservoir. In this regard, CRM is coupled with production logging tools (PLT) data to study the effects of layers. A fractional-flow model is also coupled with the developed CRM to estimate oil production. Genetic algorithm (GA) method is used to minimize the error objective function for the total production history and oil production history to evaluate model parameters. GA is then used to maximize oil production by reallocating the injected water volumes, which is the main purpose of this research. The results show that our fast method is able to model liquid and oil production history and is in good agreement with available field data. Taking into account the reservoir constraints, the optimal injection schemes have been obtained. For the proposed injection profile, the field hydrocarbon production will increase by up to 1.8% until 2016. Also, the wells will reach the water-cut constraint 2 yr later than the current situation, which increases the production period of the field.Azadeh Mamghaderi, Alireza Bastami, Peyman Pourafshar
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