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Herein, a modified synthesis method was presented and the effect of using an aqueous acetic acid solution in the process of synthesizing SQCOF was investigated. Adding a catalytic amount of aqueous solution of acetic acid as a co-catalyst has contributed to improving the quality of crystallinity. Effective parameters in the synthesis of SQCOF, including the concentration and volume of the co-catalyst and reaction solvent, were optimized. Then, the prepared SQCOF was used as a metal-free catalyst with Brønsted acid groups in the condensation reaction between 1,3-dicarbonyl compounds and primary amines. SQCOF was used under solvent-free conditions for the synthesis of enaminones at ambient temperature by mild manual grinding with a mortar and pestle and showed excellent catalytic performance in the above reaction. High performance and efficiency (62 to 96%), high TOF (833 to 1283 h−1), short reaction time, easy operation, minimizing the consumption of toxic organic solvents, absence of heavy metals in the framework and green conditions are the main advantages of this study. Also, SQCOF shows good chemical stability and recyclability (7 runs) and acts as an efficient catalyst in the synthesis of β-enaminones. [ABSTRACT FROM AUTHOR]

A high-order time discretization scheme to approximate the time-fractional wave equation with the Caputo fractional derivative of order α ∈ (1 , 2) is studied. We establish a high-order formula for approximating the Caputo fractional derivative of order α ∈ (1 , 2) . Based on this approximation, we propose a novel numerical method to solve the time-fractional wave equation. Remarkably, this method corrects only one starting step and demonstrates second-order convergence in both homogeneous and inhomogeneous cases, regardless of whether the data is smooth or nonsmooth. We also analyze the stability region associated with the proposed numerical method. Some numerical examples are given to elucidate the convergence analysis. [ABSTRACT FROM AUTHOR]

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With the growing movement of using direct current (DC) load demands, as well as DC distribution generations (DGs), the distribution system has undergone significant changes on the production and demand side. Due to alternating current (AC) and DC generators and load demands, it is not costeffective to continue in the AC distribution system. Therefore, AC/DC hybrid distribution system planning is economical despite various demands and generations. On the other hand, uncertainty in load demand and output power of DGs cause the possible behavior of the distribution system. This behavior leads to risk in the distribution system. In this paper, the AC/DC distribution system planning is discussed by considering the risk. The planning problem in the matrix laboratory and general algebraic modeling system (MATLAB/GAMS) hybrid space has been formulated and solved. Using the K-means algorithm, the uncertainty related to renewable DG output power and load demand has been modeled. To verify the proposed method, it was implemented in a sample distribution system. [ABSTRACT FROM AUTHOR]

Herein, an efficient eco-friendly protocol is reported for the continuous synthesis of enaminones using a microreactor device in the presence of a catalytic amount of cerium (III) trichloride (1 mol%) in Propylene carbonate (PC) as a non-toxic solvent. Moreover, continuous separation of the corresponding product, and recycling of the catalyst-solvent system with water is another promising advantage of this technique. Indeed, the separation of the product by water allows any required catalyst and solvent to be reapplied in the next run. In addition, this microfluidic system enabled turnover frequency (TOF) of up to 2940 h−1 for the corresponding products. The employment of these environment friendly facilitates produce the products with an excellent isolated yield up to 98%. This method performs efficiently, and would extent future applications of continuous organic, inorganic and biochemical reactions in green chemistry. [ABSTRACT FROM AUTHOR]

Aim; Autism is a pervasive developmental disorder Deficit; in sensory functions is one of the characteristics of people with autism, and usually these people show abnormality in processing and correct interpretation of auditory information. Also people with Autism show problems in communicating with others. This review article deals with the accurate understanding of Auditory processing skills of autistic children compared to normal children is done to clarify the auditory processing disorder in this group. Information & Methods This systematic review was conducted in articles published from 2002 to 2022 in the field of electrophysiological evaluations of auditory brainstem in autism spectrum disorder by searching Scopus, PubMed, Google Scholar, and Science Direct databases. Finding: Disorders were observed in the brainstem electrophysiological responses of patients with ASD compared to the normal group. The results of studies of auditory brainstem evoked responses with click stimuli showed an increase in wave V latency and I-V interpeak latency in ASD subjects compared to normal groups. Studies of brainstem evoked responses with speech stimuli also showed a decrease in amplitude and an increase in latency. Conclusion Auditory processing disorders in verbal and non-verbal stimuli in people with autism spectrum have been reported. Most studies show disorders in speech stimuli, which play a very important role in communicating. department [ABSTRACT FROM AUTHOR]

1H-Indazolo[2,1-b]phthalazine-1,6,11-trione derivatives have been synthesized through a one-pot three-component condensation of phthalhydrazide, dimedone, and aromatic aldehydes at 80°C under solvent-free conditions in the presence of a novel Co nanoparticle catalyst. The catalyst was prepared by coating Fe3O4 magnetic nanoparticles with tetraethyl orthosilicate, followed by functionalization with 3-chloropropyl(tri-methoxy)silane and 2-amino-1,3,4-thiadiazole-5(4H)-thione and complexation with cobalt(II) acetate. The superparamagnetic catalyst could be readily recovered by applying an external super magnet and used for several times without significant loss of catalytic activity. [ABSTRACT FROM AUTHOR]

In this group article, part of the teaching of advanced dynamics course has been done in the form of group-based training projects. In this project, the mechanism of a spinning ride is designed and then engineering analyzes are performed on it. The system of this spinning ride must be designed in such a way that the absolute acceleration of the human head is equal to six times the acceleration of gravity. The most basic thing to do is conceptual design. Engineering analyzes such as dynamic analysis and motion simulation; finite element analysis is also performed to obtain natural frequencies and to determine the deformations caused by loading. After completing the above steps, information will be provided about materials and manufacturing processes. Due to the fact that this project was carried out in the form of a new method of learning advanced dynamics in the form of nine groups at Sharif University of Technology and the groups competed with each other, in the end, students were surveyed about the amount of learning from this method of teaching. [ABSTRACT FROM AUTHOR]

Radar cross section reduction has been one of the most important research topics in recent years. Plasma-based stealth is a method of reducing the radar cross section, which dampens the electromagnetic waves and reduces the amount of return waves. In this paper, a coating of the radioactive nucleus 241 Am on the surface of the cylinder with a radius of 10 cm is considered and the range of the emitted alpha particles and the electron density generated in the air are obtained using the Geant4 code under standard temperature and pressure conditions. By finite element method solution, the radar cross section of the conductive cylindrical object has been simulated and extracted in the presence and absence of plasma created by alpha-particles. The obtained results show a reduction of 5–8 dB m 2 in the radar cross section in the frequency range of 2–12 GHz for specific activity source of 1 Ci/ cm 2 . [ABSTRACT FROM AUTHOR]

One of the important living organisms in stagnant waters, surface waters, water reservoirs, pools and dams is microalgae. Various methods have been developed and studied for the removal of these microscopic organisms from drinking water, of which the sedimentation or flocculation is one of the significant methods. The method is based on using sediments substance or flocculants. This study aimed to introduce feasible, harmless and suitable biological flocculants and evaluate their ability to precipitate Cyclotella diatoms. The presence of a large number of Cyclotella diatoms in water creates an unpleasant color and odor in the water. For this purpose, autoflocculation–sedimentation and bioflocculation processes were used to harvest Cyclotella. The effect of pH, mixing speed and time on harvest efficiency for autoflocculation–sedimentation and bioflocculation processes was investigated. The autoflocculation results showed that the removal efficiency increased with increasing pH, decreasing mixing speed and increasing settling time. For bioflocculation, Scenedesmus microalgae were used to isolate Cyclotella diatoms, and by examining the parameters affecting the rate of microalgae isolation, the optimal conditions have been determined. The ratio of 1:1 combination of microalgae–diatomaceous earth and pH = 10 and residence time of 120 min can yield up to 83% isolation and sedimentation of Cyclotella microalgae, which is a very efficient and inexpensive environmentally friendly method for the separation of infected microalgae from used drinking water. [ABSTRACT FROM AUTHOR]

Non-thermal plasma can be generated by gliding arc discharge units and is used in various applications including disinfection of the surface, inactivation of fungi, viruses, and bacteria. Degradation of the electrodes through prolonged use is common. It is caused by bombardment by plasma-charged particles causing changes to the structure and chemistry of its electrodes which in turn leads to a reduction in the efficiency of the plasma. In this study, the discharged plasma from a gliding arc unit was investigated using optical emission spectrometry (OES). Also studied were the electrodes of the unit after prolonged use. The structure and metallographic properties of the electrodes were evaluated using positron annihilation lifetime spectroscopy (PALS), X-ray diffraction analysis (XRD) and scanning electron microscopy—energy dispersive X-ray spectroscopy (SEM-EDX) and compared to data from new unused samples. The size of defects and holes were also compared using PALS. It was found that the intensity of species decreased significantly with prolonged use of the unit as the copper electrodes degraded. It was also found that the internal structure, as well as the surface of the used electrodes, had changed significantly compared to the unused samples, the radius of holes in the electrode material had decreased and the intensity of holes increased. Furthermore, the planes of the atomic structure of the copper electrode have moved closer. The approach developed in this study has been shown an effective non-destructive method for routine evaluation of the electrodes and maybe a development further for monitoring and quality assurance programs for maintaining high plasma efficiency as well as for research into improvements to electrode material design. [ABSTRACT FROM AUTHOR]

A prevalent problem in pomegranate (Punica granatum L.) fruit is sunburn which reduces fruit quality. This study aimed to reduce the severity of sunburn during the fruit development of pomegranate by covering them with colored netted bags. Kaolin (5%) as a traditional treatment to reduce sunburn was used to compare the efficiency of noble and traditional techniques. The netted bags used were either white, green, yellow, gray or blue. This study was carried out on a commercial cultivar (Rababe-Neyriz) over a period of two successive years. The color of the netted bags affected the anthocyanin content of arils at harvest besides minimizing the levels of sunburn. Fruit of the control group were damaged notably (32.26%) by sunburn, compared to those covered with blue and white netted bags (0%). The highest amount of ascorbic acid and the minimum amount of anthocyanin were recorded in the fruit covered with blue netted bags. The lowest degree of aril whitening (discoloration of arils) was observed when fruit were covered with white bags. Covering the fruit with gray netted bags caused the highest antioxidant activity and the highest total phenolic content in the arils. Overall, covering fruit with netted bags is recommended to prevent sunburn and to enhance fruit quality. [ABSTRACT FROM AUTHOR]

This paper studies a B-spline algorithm for calculating the solution of the multi-term time-fractional diffusion equationsM-TT-FDEs. This model describes the diffusion prossing in the fluid mechanics and provides valuable predictions. The solution of the MTT-FDEs. is discretized by means of B-spline function based on the B-spline shape technique. It is verified that the proposed strategy is more efficient in terms of computational time and accuracy in domain. [ABSTRACT FROM AUTHOR]

The present study aims to propose a robust method to detect the damage severity and location of the structural elements, focusing on the data type and acquisition method and promoting the model updating tools. The novelty of this method lies in its rotational mode shape acquisition that provides valuable information on the damage. In this method, the damaged elements were indirectly identified by detecting the healthy elements and eliminating them from the search space. Moreover, this method could minimize the modal strain energy difference between the damaged reference model and the numerical model using an optimization algorithm. An improved genetic algorithm was then employed to perform the optimization task. In this study, four numerical and two experimental damage scenarios were applied to a simply supported beam to examine the performance of the proposed method. Data acquisition systems were implemented using vision-based and accelerometer-based methods. The results indicated that this method could accurately identify the location and severity of damage using only the first mode shape since the rotational mode shapes were more sensitive to damage than the vertical mode shapes. [ABSTRACT FROM AUTHOR]

The present study aims to propose a robust method to detect the damage severity and location of the structural elements, focusing on the data type and acquisition method and promoting the model updating tools. The novelty of this method lies in its rotational mode shape acquisition that provides valuable information on the damage. In this method, the damaged elements were indirectly identified by detecting the healthy elements and eliminating them from the search space. Moreover, this method could minimize the modal strain energy difference between the damaged reference model and the numerical model using an optimization algorithm. An improved genetic algorithm was then employed to perform the optimization task. In this study, four numerical and two experimental damage scenarios were applied to a simply supported beam to examine the performance of the proposed method. Data acquisition systems were implemented using vision-based and accelerometer-based methods. The results indicated that this method could accurately identify the location and severity of damage using only the first mode shape since the rotational mode shapes were more sensitive to damage than the vertical mode shapes. [ABSTRACT FROM AUTHOR]

In this part of the study, several benchmark problems are solved to evaluate the performance of the existing strain-based membrane elements, which were reviewed in the first part. This numerical evaluation provides a basis for comparison between these elements. Detailed discussions are offered after each benchmark problem. Based on the attained results, it is concluded that inclusion of drilling degrees of freedom and also utilization of higher-order assumed strain field result in higher accuracy of the elements. Moreover, it is evident that imposing the optimal criteria such as equilibrium and compatibility on the assumed strain field, in addition to reducing the number of degrees of freedom of the element, increases the convergence speed of the resulting strain-based finite elements. [ABSTRACT FROM AUTHOR]

Since the introduction of the finite element approach, as a numerical solution scheme for structural and solid mechanics applications, various formulation methodologies have been proposed. These ways offer different advantages and shortcomings. Among these techniques, the standard displacement-based approach has attracted more interest due to its straightforward scheme and generality. Investigators have proved that the other strategies, such as the force-based, hybrid, assumed stress, and assumed strain provides special advantages in comparison with the classic finite elements. For instance, the mentioned techniques are able to solve difficulties, like shear locking, shear parasitic error, mesh sensitivity, poor convergence, and rotational dependency. The main goal of this two-part study is to present a brief yet clear portrait of the basics and advantages of the direct strain-based method for development of high-performance plane finite elements. In this article, which is the first part of this study, assumptions and the basics of this method are introduced. Then, a detailed review of all the existing strain-based membrane elements is presented. Although the strain formulation is applicable for different types of structures, most of the existing elements pertain to the plane structures. The second part of this study deals with the application and performance of the reviewed elements in the analysis of plane stress/strain problems. [ABSTRACT FROM AUTHOR]

Nowadays, academics have paid special attention to global warming, because it has several issues such as urban heat island (UHI) related to the quality of life. For this purpose, a spatial decision support system (SDSS) has been developed to investigate the effect of parcels' roof covering type on surface heat island (SHI) values and its variation at the neighborhood scale in Tehran, Iran. This SDSS, as the innovation of the present research, consists of two main steps including estimating the UHI value in the study area and adopting the optimum set of parcels to change their roofs' cover with three types of vegetation, high-albedo material, and flagstone. The first step is accomplished by aggregating various indices related to land cover obtained from Landsat 8 images. The aggregation is done by linear regression method (LRM) with an RMSE and R2 equal to 0.942 and 0.897, respectively. Then, the genetic algorithm was used to select the optimal subset, including 10% of the parcels in the area, to change their roof covering type based on minimizing the UHI's variation. The standard deviation obtained after the changes improved from 13.222 to 10.781 °C. The results indicate that to control UHI in the center of the region, it is necessary to inhibit UHI effects at the boundary of the study area with vegetation roof covering since flagstone and high-albedo materials have local effects on controlling the UHI effects. [ABSTRACT FROM AUTHOR]

A reliable forecast of the prices of agricultural commodities can help to allocate resources optimally, enhance efficiency and farmer income, and alleviate fluctuations. Given the importance of accurate forecasts, the present paper investigates how one can forecast greenhouse tomato prices at one, two, three, and six-month horizons using different support vector machines and artificial neural network algorithms. The data on variables affecting the price of greenhouse tomatoes were collected through a field study for a shortterm period from November 2014 to January 2017. The wholesale price of the crop was drawn from a market study for this period. The results show that the trend forecasted through General Regression Neural Network along with activating function of reciprocal is more efficient to estimate the training data. The Epsilon-SVR SVM acquisition pattern alongside the linear activating function was taken into consideration to estimate the testing data in an efficient way for two-month, three-month or biannual periods. [ABSTRACT FROM AUTHOR]

In the present study for the first time, a novel polyacrylonitrile-silver nanocomposite nanofiber was synthesized by electrospinning for adsorbing sulfur compounds in natural gas condensate. The synthesized material was characterized by SEM, EDAX, and XRD. The presence of C, N, O, and Ag proved that the composite was synthesized successfully. In order to achieve the best adsorption conditions, the effect of contact time, adsorbent dosage and initial sulfur compound concentration was examined. Under optimal values, efficiency of greater than 90% was found. In addition, different isotherms and kinetics models were tested to describe the sorption process. It was found that Freundlich (0.9900) was superior to Langmuir (0.9688), Temkin (0.9648) and Dubinin-Radushkevich (0.8273) models, revealing that sulfur compounds tend to for, multilayers on the heterogeneous surface of polyacrylonitrile-silver nanocomposite nanofiber. The energy value of the adsorption was 23.57 kJ/mol, indicating chemisorption reactions. Based on kinetics studies, the desulfurization by nanofibers followed Pseudo-second-order and Elovich kinetics. Finally, the desulfurization function of nanocomposite was studied and validated using adsorbent columns. The obtained results demonstrate polyacrylonitrile-silver nanocomposite nanofiber as a promising material in the field of desulfurization. [ABSTRACT FROM AUTHOR]

A horizontal axis wind turbine power generation depends upon the aerodynamic performance of its blades. Flow separation is one of the phenomena that causes power loss and consequently decreasing the wind turbine output generation. Since usually the local angle of attack in the inner and middle parts of a blade is much greater than the local angle of attack in the separation onset, the blade section encounters a highly separated flow. Hence, flow control methods are applied in order to reduce or weaken the negative effects of the separation. This paper investigates the effects of the passive flow control method for a horizontal axis wind turbine using validated three-dimensional DES (detached eddy simulation) on an S809 split airfoil. The split in the airfoil thickness causes the flow from the high-pressure zone under the lower surface is injected into the separated area over the upper surface, transporting external energy to the separated zone, hence weakening the separated area. As the result show, the overall performance of this method depends on parameters such as split locations on the airfoil pressure and suction surfaces, the direction of the jet flow with respect to the freestream wind and also the thickness of the split. In this research, two different split locations and four thickness values of 0.5, 1, 2 and 4 percent of chord length are simulated at a range of AOA from 0 to 25 degrees. Noticeably, the results demonstrate that for an appropriate split exit location, the thickness value of 2 and 4 percent of the chord are generated more lift force. The average increase of lift coefficient for these split airfoils at a high angle of attack (17, 20, 22 and 25) are 68.5 and 55.8 percent respectively. [ABSTRACT FROM AUTHOR]

In this study, we discuss the problem of estimating ρ = P (X > Y) , when X and Y are two independent power Lindley random variables, based on progressively type II right censored order statistics. The maximum likelihood estimator of ρ and its asymptotic distribution, asymptotic interval estimator of ρ, Bayesian point estimators for ρ under symmetric and asymmetric loss functions as well as credible intervals for ρ are achieved when X and Y have a common parameter. Since it seems that the integrals pertaining to the Bayes estimation cannot be obtained in explicit forms, we propose the Metropolis-Hastings within Gibbs algorithm to find the approximate Bayes estimates of ρ. A simulation study is given in order to evaluate the proposed estimators and compare the different methods, developed in the paper. The corresponding results for the general case (when X and Y have no common parameters), as well as two examples, are also provided. The paper finishes with some remarks. [ABSTRACT FROM AUTHOR]

A novel magnetic Co nanoparticle catalyst was prepared by coating Fe304magnetic nanoparticles with tetraethyl orthosilicate functionalized with (3-chloropropyl)trimethoxysilane and 2-amino-5-mercapto-1,3,4-thiadiazole ligands followed by complexation with Co(OAc)4. The catalyst was then characterized and applied for the synthesis of various tetrazoles by the reactions of amines with sodium azide and triethyl orthoformate in solvent-free conditions at 100°C. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the effects of different early weaning programs on growth performance and blood parameters of dairy calves. To meet this objective, thirty Holstein calves with initial body weight of 36 ± 5 kg were randomly assigned at birth to one of the three weaning programs. Experimental groups were: 1) starter diet and whole milk from birth to 6 weeks and weaning at 42 d old (6WW)), 2) starter diet and whole milk from birth to 9 weeks and weaning at 63 d old (9WW) and 3) starter diet and whole milk from birth to 12 weeks and weaning at 84 d old (12WW). Starter diet and water were available ad libitum throughout the experiment. Daily starter intake and growth performance of calves were measured until d 90 of life for all groups. Body weight (BW) and starter intake in all measured periods (on d 28, 56 and 84) did not differ between experimental groups. Calves weaned at 42 d (6WW) had higher average daily gain (ADG) in second month than 9WWand 12WWgroups (P<0.05). Calves reared in 6WW group had significantly greater total ADG values than calves weaned on 63 and 84 d (P<0.05). Total feed conversation ratio affected by experimental treatments and was lowest in 6WWcalves (P<0.05). Body length, heart girth and withers height of calves did not differ among treatments at 28, 56 and 84. Plasma cholesterol concentration of calves weaned in 6WWgroup was lower (P<0.05) than calves weaned in 9WW and 12WW. Under the conditions of this study, the results suggest that calves weaned at 42 d were more efficient at utilizing dry matter intake for body weight (BW) gain and growth. [ABSTRACT FROM AUTHOR]

In this paper, we derive a closed form equation for the joint probability distribution fRz,Θz(rz,θz) of the amplitude Rz and phase Θz of the ratio Z=XY of two independent non-zero mean Complex Gaussian random variables X∼CN(νxejϕx,σx2) and Y∼CN(νyejϕy,σy2). The derived joint probability distribution only contains a confluent hypergeometric function of the first kind 1F1 without infinite summations resulting in computational efficiency. We further derive the probability distribution for the ratio of two non-zero mean independent real Rician random variables containing an infinite summation generated by the estimation of the Cauchy product of equivalent series of two modified Bessel functions. [ABSTRACT FROM AUTHOR]

The current study illustrated the possible positive effects of flavonoids present in the leaves of Mespilus germanica on cognitive performance, learning and memory function in an intra-cerebroventricular streptozotocin-induced Alzheimer's disease model in male Wistar rats. Five groups (saline-saline control, streptozotocin-saline, and streptozotocin with different doses of flavonoids, 5, 10 and 20 mg/kg) of rats were examined. Rats received different doses of Mespilus germanica flavonoids or saline over three weeks starting one day before surgery. Next, they were assessed using a learning and memory test. After subjected to the behavioral test, the animals were perfused and their brains were fixed with paraformaldehyde 4 % and the tissue was further processed. Finally, the density of intact neurons in the hippocampal CA1 area in all groups was investigated. The results revealed that injection of streptozotocin significantly reduced cognitive function, memory retention as well as CA1 intact neurons compared to the control group. Flavonoids extracted by Mespilus germanica considerably eradicated the negative effects of streptozotocin. Accordingly, Mespilus germanica leaf flavonoids can improve cognitive deficits resulted from injection of streptozotocins. [ABSTRACT FROM AUTHOR]

As a prophylactic cancer vaccine, human amniotic membrane epithelial cells (hAECs) conferred effective protection in a murine model of colon cancer. The immunized mice mounted strong cross‐protective CTL and antibody responses. Tumor burden was significantly reduced in tumor‐bearing mice after immunization with hAECs. Placental cancer immunotherapy could be a promising approach for primary prevention of cancer. In spite of being the star of therapeutic strategies for cancer treatment, the results of immunotherapeutic approaches are still far from expectations. In this regard, primary prevention of cancer using prophylactic cancer vaccines has gained considerable attention. The immunologic similarities between cancer development and placentation have helped researchers to unravel molecular mechanisms responsible for carcinogenesis and to take advantage of stem cells from reproductive organs to elicit robust anti‐cancer immune responses. Here, we showed that vaccination of mice with human amniotic membrane epithelial cells (hAECs) conferred effective protection against colon cancer and led to expansion of systemic and splenic cytotoxic T cell population and induction of cross‐protective cytotoxic responses against tumor cells. Vaccinated mice mounted tumor‐specific Th1 responses and produced cross‐reactive antibodies against cell surface markers of cancer cells. Tumor burden was also significantly reduced in tumor‐bearing mice immunized with hAECs. Our findings pave the way for potential future application of hAECs as an effective prophylactic cancer vaccine. [ABSTRACT FROM AUTHOR]

Indoor positioning is a fundamental requirement of many indoor location-based services and applications. In this paper, we explore the potential of low-cost and widely available visual and inertial sensors for indoor positioning. We describe the Visual-Inertial Odometry (VIO) approach and propose a measurement model for omnidirectional visual-inertial odometry (OVIO). The results of experiments in two simulated indoor environments show that the OVIO approach outperforms VIO and achieves a positioning accuracy of 1.1% of the trajectory length. [ABSTRACT FROM AUTHOR]

Based on the theory of beams on elastic foundations, a new analytical solution for calculating the natural frequencies of reinforced-soil retaining walls is presented. The assumed retaining wall is geosynthetic-reinforced, with a full-height rigid concrete facing (a GRS-FHR wall). The current study takes into account the rigid body motion of these walls for the first time, and two analytical formulae for calculating the natural frequencies of the rigid mode of deformation for reinforced retaining walls are presented through an exact solution. Next, applying the energy method, a new analytical formula for calculating the natural frequency of the flexural deformation mode is developed. Another innovation is the modeling of the foundation soil with both rotational and translational springs, which makes it possible to consider rocking and sliding deformation modes for retaining wall motion. Moreover, the effect of backfill soil interaction is taken into consideration by translational springs along the wall. The results thus obtained are then compared with numerical analysis using Ansys software, and an excellent agreement was observed. [ABSTRACT FROM AUTHOR]

Aim: Diazinon (DZN) is one of the most important organophosphorus compounds used to control pests in agriculture in many countries. Several studies have shown that exposure to DZN may alter protein expression in the liver. In order to further investigate the mechanism of DZN toxicity, differentially expressed ATP-interacting proteins, following subacute exposure to toxin, were separated and identified in rat liver. Main methods: Male rats were equally divided into four groups: control (corn oil) and DZN (15 mg/kg) by gavage once a day for 4 weeks. After homogenization of liver tissue, lysates were incubated ATP-sepharose beads. After several washes, ATP-interacting proteins were eluted and separated on 2-D polyacrylamide gels. Deferentially expressed proteins were cut and identified using matrix-assisted laser desorption/ionization/time-of-flight and Mascot database. Identified proteins were classified according to their biological process using protein analysis through evolutionary relationships (PANTHER) Web site. Key finding: In this work, we showed that several key proteins involved in biological processes such as antioxidant system, oxidative stress, apoptosis, and metabolism were differentially expressed after subacute exposure to DZN. [ABSTRACT FROM AUTHOR]

Polyethylenimine (PEI) is a polycation widely used for successful gene delivery both in vitro and in vivo experiments. However, different studies showed that PEI could be cytotoxic to transfected cells, and the mechanism of toxicity is poorly understood. Identification of PEI-interacting proteins may help in understanding the toxicity pathways. In this study, we investigated proteins that could interact with PEI in human colorectal adenocarcinoma cells (HT29). In order to identify the proteins interacting with PEI, PEI was immobilized to sepharose beads as solid matrix. The HT29 cell lysate were passed through the matrix. PEI-bound proteins were isolated, and further separation was performed by two-dimensional gel electrophoresis. After gel digestion, proteins were identified by matrix-assisted laser desorption/ionization–time-of-flight (TOF)/TOF mass spectrometry. Our data indicated that most of the identified PEI-interacting proteins such as shock proteins, glutathione-S-transferases, and protein disulfide isomerase are involved in apoptosis process in cells. Thus, although this is a preliminary experiment implicating the involvement of some proteins in PEI cytotoxicity, it could partly explain the mechanism of PEI cytotoxicity in cells. [ABSTRACT FROM AUTHOR]

In the fusion devices, ions, H atoms, and H2 molecules collide with dust grains and exert stochastic torques which lead to small variations in angular momentum of the grain. By considering adsorption of the colliding particles, thermal desorption of H atoms and normal H2 molecules, and desorption of the recombined H2 molecules from the surface of an oblate spheroidal grain, we obtain diffusion coefficients of the Fokker-Planck equation for the distribution function of fluctuating angular momentum. Torque coefficients corresponding to the recombination mechanism show that the nonspherical dust grains may rotate with a suprathermal angular velocity. [ABSTRACT FROM AUTHOR]

A correction to the article on "Silver tungstate nanostructures: electrochemical synthesis and its statistical optimization" in the June 10, 2015 issue is presented.

We survey a model for theoretical study of the interaction of hydrogen and dust surface and apply our results for dusty plasmas to fusion devices. In this model, considering the mobility of ad-atoms from one physisorbed, or chemisorbed site, to other one by thermal diffusion, we describe the formation of H2 on grain surfaces. Finally, we calculate the formation rate on the high temperature dust surfaces for a range of temperature and density in typical conditions of divertor of tokamak. [ABSTRACT FROM AUTHOR]

An efficient, rapid, simple, and inexpensive liquid phase microextraction method, called floating organic drop, combined microextraction with electrothermal atomic absorption spectroscopy was proposed for the determination of trace amounts of cobalt in several wastewater samples. Samples were prepared from Tehran oil refinery. In this technique, preconcentration of Co2+was carried out by 2-nitroso-1-naphthol as complexing agent, from a 25-mL sample solution into a few microliters ofn-octanol that formed by agitation with a stirring bar for a desired time. After coalescence of fine droplets on the surface, 10 µL of the organic phase was withdrawn with a microsyringe, injected into a graphite tube, and cobalt content determined by electrothermal atomic absorption spectrometry. Under optimum conditions, the detection limit of Co2+was 4 ng L−1, with a preconcentration factor of 155. The relative standard deviations for 0.1 µg L−1of Co2+in water was 4.3% (n= 8). A dynamic linear range of 0.008–0.2 µg L−1with correlation coefficientR2= 0.994 was observed. The proposed method was applied successfully to the determination of Co2+in oil refining wastewater samples. [ABSTRACT FROM PUBLISHER]

Silver tungstate (AgWO) nanoparticles were synthesized by a simple electrochemical method with the aid of silver electrode and sodium tungstate as starting reagents. In this study, synthesis conditions of silver tungstate nanoparticles were optimized by Taguchi robust design. Besides, the effects of several synthesis conditions such as tungstate ion concentration, applied voltage, stirring rate, and reaction temperature on the particle size of product were investigated by SEM images. Furthermore, the significance of these factors on the diameter of silver tungstate nanoparticles was evaluated by the analysis of variance and the optimum conditions for the preparation of silver tungstate nanoparticles by electrochemical method was investigated. The resulted nanoparticles were characterized by different routes, i.e., XRD, FTIR, SEM, and PL analysis. Also, the optical band gap corresponding to the resulted AgWO nanoparticles was predicted to be 2.75 eV. [ABSTRACT FROM AUTHOR]

A single-task functional magnetic resonance imaging (fMRI) experiment may only partially highlight alterations to functional brain networks affected by a particular disorder. Multivariate analysis across multiple fMRI tasks may increase the sensitivity of fMRI-based diagnosis. Prior research using multi-task analysis in fMRI, such as those that use joint independent component analysis (jICA), has mainly assumed that brain activity patterns evoked by different tasks are independent. This may not be valid in practice. Here, we use sparsity, which is a natural characteristic of fMRI data in the spatial domain, and propose a joint sparse representation analysis (jSRA) method to identify common information across different functional subtraction (contrast) images in data from a multi-task fMRI experiment. Sparse representation methods do not require independence, or that the brain activity patterns be nonoverlapping. We use functional subtraction images within the joint sparse representation analysis to generate joint activation sources and their corresponding sparse modulation profiles. We evaluate the use of sparse representation analysis to capture individual differences with simulated fMRI data and with experimental fMRI data. The experimental fMRI data was acquired from 16 young (age: 19–26) and 16 older (age: 57–73) adults obtained from multiple speech comprehension tasks within subjects, where an independent measure (namely, age in years) can be used to differentiate between groups. Simulation results show that this method yields greater sensitivity, precision, and higher Jaccard indexes (which measures similarity and diversity of the true and estimated brain activation sources) than does the jICA method. Moreover, superiority of the jSRA method in capturing individual differences was successfully demonstrated using experimental fMRI data. [ABSTRACT FROM AUTHOR]