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The cross-sections of deuteron-induced nuclear reactions suitable for ion beam analysis, measured in different laboratories, are often significantly different. In the present work, differential cross-sections of 27Al(d,p) and 27Al(d,α) reactions were measured, and the cross sections benchmarked with thick target spectra obtained from pure aluminium for the first time in two independent laboratories. The 27Al(d,p) and (d,α) differential cross-sections were measured between 1.4 and 2 MeV at scattering angles of 165°, 150°, and 135° in the VDGT laboratory in Tehran (Iran), and the same measurements for detector angle of 150° were repeated from scratch, including target making, with independent equipment on the SAFIR platform at INSP in Paris (France). The results of these two measurements at 150° are in good agreement, and for the first time a fitted function is proposed to describe the Al-cross sections for which no suitable theoretical expression exists. The obtained differential cross-sections were validated through benchmarking, by fitting with SIMNRA deuteron-induced particle spectra obtained from a high purity bulk Al target at both labs for deuteron incident energies between 1.6 and 2 MeV. The thick target spectra are well-reproduced. The evaluated and benchmarked cross sections have been uploaded to the ion beam analysis nuclear data library database (www-nds.iaea.org/ibandl/).

IntroductionIn Iran, due to population growth and rising costs in the coming years and supply of food needs, there should be solutions for more production, with less waste, so the presence of robots can be justified for more production, reducing waste and reducing current costs. The present study investigates the factors affecting the adoption of automation in agriculture in Ardabil within the framework of the constructive factors of "Technology Acceptance Model" and examining the applicability of this model in the research community.Materials and MethodsIn the present study, the conceptual model factors include perceived usefulness, perceived ease of use, attitude toward use, and the intention to use, that affect the dependent variable of automation. Six of the first hypotheses of this study are based on the study of the significant relationships between each pair of variables in the framework of the "Technology Acceptance Model", and the applicability of the "Technology Acceptance Model" in the research community is defined in the seventh hypothesis. The method of this research is surveyed and data collection tool is a questionnaire designed based on technology acceptance model (TAM). In this research, the population of 27670 people were investigated that include university staffs-farmers and managers of ministry of agriculture in Ardabil. Using Cochran formula, 380 of them were selected in the form of stratified random sampling as sample size. Validity was confirmed by experts in agricultural management and mechanization, using Cronbach's alpha (0.958). Also, descriptive and inferential statistics were used and data analysis was performed using SPSS20 software.Results and DiscussionThe findings of this study showed that the technology acceptance model with a final determination coefficient of 635.0 was used in the studied population, which means that the applicability of the model (TAM) was very suitable for agricultural study in Ardabil. The priorities for the effects of the variables of the technology acceptance model for the actual use of automation were perceived ease of use (1.284), perceived usefulness (1.280), intention to use (0.954) and attitude (0.478) respectively.Using the results of modeling, it was also found that the correlation coefficient between individual factors and the perceived usefulness of the application of automation has a strong relationship. The correlation coefficient between the two variables is negative and indicates that with increasing individual factors, the level of perceived usefulness of the use of automation also decreases, and vice versa. However, experience, self-confidence and financial situations, level of education, land area, number of family workforce, have not greatly increased productivity and reduced production costs and helped agricultural activities (understanding the usefulness of technology).The relationship can be considered as the most important factor in holding weak and undesirable classes in creating knowledge, experience and poor self-confidence of the respondents towards accurate agricultural technology. In these classes, the content should be presented in a more specialized and practical way to make them understand the usefulness of precision agricultural technology.According to the results of this study, the organization of workshops and periodic training courses, as well as the introduction of this technology in journals and publications and social media is recommended.ConclusionsConsidering the confirmation of the hypotheses of this research and the priorities obtained for the effects of the structures of the technology acceptance model, it can be concluded that as it is known, the two main constituents of this model, perceived ease of use and perceived usefulness have had a significant impact on the amount of technology used, or, in other words, technology acceptance. The perceived usefulness is the most effective factor in the actual use of automation. In following, perceived ease of use, intention to use, and the attitude was ranked respectively.

Erosion has been recognized as one of the major threats for industries involving multiphase transportation pipelines. Within the last decades, effective parameters on wear pattern have been identified. As a result, the (famous) V-shaped erosion profile has been detected for the pipes' elbow section. In this study, CFD is employed to investigate the erosion mechanism on the square duct elbows. A novel erosion pattern has been observed for square ducts in comparison with the pipes. The impact of several parameters (particle and flow velocity, secondary flow, turbulent intensity, particle streamline) has been inspected as well. It has been led to the conclusion that the erosion rate of square ducts is lower than common pipes, especially when either higher flow velocities or bigger particles size are employed.

In this paper, a novel method for loss reduction and efficiency optimization of the high frequency flyback transformers is proposed based on rearrangement of the windings. According to detailed analysis of the high frequency flyback transformer using FEM technique, a novel and simple approach for its design improvement and loss reduction is introduced. It is shown that leakage flux scattering in core air-gap is one of the main reasons for hot-spot point generation in the windings. So, this problem and its possible solutions are analyzed in more detail. Moreover, FEM analysis is used for investigation of the developed method and rearrangement of the winding structure. In fact, some winding structures for efficiency improvement of the flyback transformer is presented and analyzed. Finally, in order to verify accuracy and effectiveness of the developed approach, simulation and experimental results are presented. Experimental results show 3.3% improvement in total efficiency of the converter and 41.78% loss reduction in the flyback transformer.

The blood flow in the skin of the temporal region and the functional state of the muscles were investigated using the speckle-optical method. It is shown that the speckle-optical method can be used to objectify the skin blood flow and to evaluate vascular reactivity during breath-holding and hyperventilation. Obtained objective data of the tonic state of the anterior tibial muscle of healthy people can be used as indicators of the norm in the clinic for comparison with the results of examinations of patients with diseases of the motor sphere and the pathology of the neuromuscular apparatus, as well as in sports medicine.

The possibility of application of the speckle-optical method for the objectivization of cutaneous blood flow and evaluation of vascular reactivity with respiratory arrest and hyperventilation is shown. 21 patients with arterial aneurysms (AA) of the brain were examined. Recording of blood flow was carried out on skin of the temporal region on both sides. Violation of vascular reactivity during respiratory tests in the form of development of paradoxical reactions or reduction of adequate responses to HF and HB on the side with AA has been established. The most informative are the power of the spectrum and the mean frequency of the spectrum.

The cross-sections of deuteron-induced nuclear reactions suitable for ion beam analysis, measured in different laboratories, are often significantly different. In the present work, differential cross-sections of 27 Al(d,p) and 27 Al(d,α) reactions were measured, and the cross sections benchmarked with thick target spectra obtained from pure aluminium for the first time in two independent laboratories. The 27 Al(d,p) and (d,alpha) differential cross-sections were measured between 1.4 and 2 MeV at scattering angles of 165°, 150°, and 135° in the VDGT laboratory in Tehran (Iran), and the same measurements for detector angle of 150° were repeated from scratch, including target making, with independent equipment on the SAFIR platform at INSP in Paris (France). The results of these two measurements at 150° are in good agreement, and for the first time a fitted function is proposed to describe the Al-cross sections for which no suitable theoretical expression exists. The obtained differential cross-sections were validated through benchmarking, by fitting with SIMNRA deuteron-induced particle spectra obtained from a high purity bulk Al target at both labs for deuteron incident energies between 1.6 and 2 MeV. The thick target spectra are well-reproduced. The evaluated and benchmarked cross sections have been uploaded to the ion beam analysis nuclear data library database (www-nds.iaea.org/ibandl/).

Investigating the dynamical behavior of a system is an effective method to predict and control its future behavior. Studying the dynamic behavior of a virus can prevent the pathogenicity of a virus and save human lives during the disease epidemic. If the transmission of information from the virus genome to the environment is locked, the pathogenicity of the virus stops. Information transmission can be checked via the investigation of the spin information transport. In the current study, we have characterized the dynamical behavior of the virus by studying the spin transport through its RNA chain to estimate the information transfer path in the system. A voltage generator with adjustable frequency as a control system has been designed using the control theory of chaotic systems. Our aim is disturbing and reduces the transmitted information from viruses to the environment. The external stimuli can propel the system to the locked information transfer situation. Applying an external field noise with a specific frequency range (200–500 GHz) controlled through the external controller system can destroy the information transmitted by the virus to the environment. Disturbance intensity as a control parameter adjusts the external field frequency to push the system to the chaotic behavior which will be able to lock the information transfer and then prevent the spread of the epidemic.

Toxoplasmosis, a parasitic disease caused by Toxoplasma gondii, has possible irreparable consequences in immunocompromised patients and fetuses. Finding an effective method of prevention, such as vaccination, is crucial because of the global distribution of the parasite and the lack of effective anti-toxoplasmosis drugs. The Sag1 and Gra7 antigens of T. gondii can induce strong humoral and cell-mediated immune responses. Therefore, to develop a novel DNA vaccine against toxoplasmosis, we prepared a eukaryotic construct expressing the Sag1 and Gra7 genes of T. gondii (RH strain). We then verified the ability of this construct to produce the corresponding Sag1 and Gra7 antigens in mammalian cells. Using specific primers, the complete coding sequences of Sag1 and Gra7 genes were amplified by polymerase chain reaction (PCR) from the genomic DNA of T. gondii. Then, both genes were subcloned into pVitro2-neo-mcs plasmid. The pVitro-Sag1-Gra7 construct was subjected to colony PCR, enzymatic digestion, and sequencing to confirm successful subcloning. Sag1 and Gra7 expression in HeLa cells was investigated. Sag1 and Gra7 were successfully subcloned in pVitro2-neo-mcs plasmid. The expression of Sag1 and Gra7 in HeLa cells was confirmed through Western blot analysis. The recombinant pVitro-Sag1-Gra7 construct that simultaneously produces Sag1 and Gra7 antigens in one mammalian cell may be used to develop a novel protective vaccine against toxoplasmosis.

Toxoplasmosis is an infectious disease caused by the coccidian parasite Toxoplasma gondii. Diagnosis is based on serological methods with detection of specific IgG and IgM antibodies. The present study was performed to compare the sensitivity and specificity of soluble antigen of T. gondii, RH strain obtained from mice and cell culture in ELISA method. Tachyzoites of T. gondii, RH strain that inoculated in mice peritoneum were collected. At the same time, tachyzoites were harvested from HeLa cell culture that infected with the parasite. Soluble antigen was prepared and ELISA method performed on 100 serum samples that were collected from different laboratories in Tehran, Iran. Commercial Trinity kit was used as gold standard. The sensitivity and specificity of T.gondii soluble antigen were higher in antigens that obtained from cell culture in comparison with mice peritoneum. T. gondii cell culture derived antigen has high sensitivity and specificity in ELISA test.

A family of reticulocyte-binding proteins of Plasmodium vivax (PvRBP) is localised at the apical pole of the merozoites and appears to bind to reticulocytes specifically and has also been involved in identifying host cells. Protein component produced by the Pvrbp2c gene is highly antigenic. The aim of this study was to detect the genetic diversity in the Pvrbp2c gene of Iranian P. vivax field isolates using the polymerase chain reaction- restricted fragment length polymorphism (PCR-RFLP) technique. A total of 79 P. vivax malaria patients with fever participated in the study. Alu1 and Apo1 restriction enzymes were independently used to identify allelic variants of the Pvrbp2c gene. All of the samples exhibited a single band of about 2 Kb in nested PCR. Among 79 P. vivax field isolates in the RFLP with Apo1 and Alu1 restriction enzymes, 15 and nine patterns were observed, respectively. In total, 24 various patterns were detected from the combined findings of both Alu1 and Apo1 fragments in RFLP. This study revealed that Pvrbp2c has genetic diversity in southeast Iran. Genotyping of Pvrbp2c not only shows the heterogeneity of P. vivax but also provides important information that could be used to control vivax malaria.

The spent bleaching clays (SBC) of vegetable oil refining plants have residual vegetable oil contents ranging from 17 to 40 wt%. The common worldwide practice of landfilling such spent clays imposes inevitable environmental hazards. The extraction of oil from a spent clay will not only alleviate this problem, but can also provide an oil source for processes, such as transesterification for the production of alcohol-esters. In-situ transesterification of the residual oil within SBC is an even more attractive idea, as it can eliminate the extraction step from the process. In this study, in-situ transesterification on the spent bleaching clay of a local vegetable oil plant was investigated experimentally. Furthermore, optimum operating conditions were determined for a number of parameters influencing the conversions, including reaction temperature, ethanol-to-SBC ratio, alkali catalyst type, and catalyst-to-SBC mass ratio. The experiments were designed by the response surface method based on the central composite approach (RSM-CCD model). The results were analyzed using the analysis of variance method (ANOVA) to investigate the effect of the parameters on the efficiencies of the biodiesel produced and the oil removed from the initial SBC. Within the ranges investigated, the maximum conversion to ethyl-ester was 72.90% at the optimum conditions of a reaction temperature of 73.2 °C, reaction time of 4.5 h, ethanol/SBC ratio of 4.2 ml/g, while using NaOH alkali catalyst with a catalyst-to-SBC mass ratio of 4.33%.

In this study, effects of milling conditions on mechanical and microstructural properties of AISI 316 stainless steel powder were examined. Milling process was performed at ambient and cryogenic (−100 to −90 °C ) temperatures for 1–12 h. The cryogenic tests were performed using liquid nitrogen without direct contact to the main powder. In order to investigate the effect of milling parameters on final properties of sintered samples, hot pressing was performed on selected as-milled powders at 1150 °C for 1 h under 65 MPa pressure. XRD analysis on as-milled powders confirmed the phase transformation of austenite ( γ ) to α ' martensite in all samples. It was also evident from quantitative measurements carried out by Rietveld refinement method that the α ' weight fraction was a function of time and temperature. Based on this method, for all phases, crystallite size reduced to nanometer regime. Microstructural analysis for all samples was carried out by Scanning Electron Microscopy (SEM) equipped with Energy Dispersive Spectroscopy (EDS) that confirmed Rietveld analysis results. For as-sintered samples, relative density and Vickers hardness measurement were also performed to assess the physical and mechanical properties.

The purpose of this study was to describe the steps of implementing the Realistic Mathematics Education (RME) approach in teaching geometry in elementary schools. This research uses collaborative action research between lecturers, students, and teachers in 2019 at one of the primary schools in Central Java. Data collection techniques through observation, interviews, and tests. The result of the research is that the implementation steps of the RME approach include: (a) Understanding contextual problems. (b) Describing contextual problems, (c) Solving contextual problems, (d) Comparing and discussing answers, and (e) Concluding. The implementation of the RME approach is proven to improve mathematics learning outcomes about geometry.

This paper presents an integrated model based on a compromised solution method to solve fuzzy belief multi-objective large-scale nonlinear programming (FBMOLSNLP) problem with block angular structure. A new method is proposed to transfer each belief decision-making problem into some fuzzy problems. Furthermore, we propose a new compromise method of decision-making as one of the most efficient methods based on the particular measure of closeness to the ideal solution to aggregate multi-objective decision-making (MODM) problems into a single problem. The decomposition algorithm based on Dantzig–Wolfe is utilized to reduce the large-dimensional objective space into a two-dimensional space. Then, Zimmerman method is applied to transfer each bi-objective to a single-objective. Moreover, TOPSIS and VIKOR are utilized as two independent solution methods to aggregate each multi-objective sub-problem. Finally, a new single-objective nonlinear programming problem is solved to find the final solution. To justify the proposed model, two illustrative examples are provided, and the results of three decision methods are compromised.

Forced convective heat transfer in a microchannel heat sink (MCHS) using CuO/water nanofluids with 0.1 and 0.2 vol% as coolant was investigated. The experiments were focused on the heat transfer enhancement in the channel entrance region at Re

Background and objectives: Dried pulps and peels of Ziziphus jujuba fruits are commonly applied as food because of their high nutritional value. It has been widely used in traditional medicine as laxative, tonic, wound healing agent and appetizer. The aim of this study was to evaluate the anti-melanogenic effects of Z. jujuba fruit. Methods: Fruit extracts were obtained by two different extraction methods, percolation (cold extraction) and soxhlet (hot extraction) using methanol 80% as the solvent. The total phenolic and flavonoid contents, DPPH radical scavenging activity and anti-tyrosinase capacity of the MeOH extracts from Z. jujuba fruits were evaluated in vitro. In addition, the effects of fruit extracts on the melanin content and cytotoxicity on human melanoma SKMEL-3 cells were determined after 72 hours. Results: The amount of total phenolic and flavonoid contents of the cold extract were found higher in comparison to the hot extract. Moreover, the antioxidant (SC50 =1.40 mg/mL) and anti-tyrosinase activities (IC50 = 0.54 mg/mL) of the cold extract were significantly stronger than the hot extract. At the dose of 500 μg/mL, the cold extract showed weaker toxicity to the melanoma cells than the hot extract. Melanin content of the cold extract was reduced to 30% at this concentration, while the hot extract had no inhibitory effect on melanin formation. Conclusion: The results showed that the percolation method was more suitable for extraction of the (poly) phenolics from Z. jujuba fruits. In addition, the results of tyrosinase activity and melanin content assays suggested that the cold extract of Z. jujuba fruit can be considered as a dermatological whitening agent in skin care products.

Tracing of buried plastic pipes by the means of acoustic methods has become a subject undergoing intense study, thanks to the encouraging results in comparison to other commercial techniques. The current acoustic technique for tracing underground plastic pipes involves the excitation of the pipe wall or the contained fluid at a fixed location. As wave attenuations are generally large for plastic water pipes, signals cannot be sensed at large distances away from the exciter's location, or at high frequencies. Although in-pipe sources allow tracking of the pipe at larger ranges, current acoustic exciters are not always appropriate, being cumbersome and too large to fit into smaller pipes. In this work, two types of pneumatic device were evaluated, with the aim of generating high amplitude signals at low frequencies and with the ability of accessing pipes with a wide range of diameters, down to 1 cm. The devices are experimentally characterised by a series of laboratory tests in a water-filled plastic pipe section. A comparison of the acoustic power transmission to a fluid filled pipe between a standard electro-acoustic device, an electromagnetic shaker, and the pneumatic ones is made.

We perform a new extraction of polarized parton distribution functions (PPDFs) from the spin structure function experimental data in the fixed-flavor number scheme (FFNS). In this analysis, we include recent proton and deuteron spin structure functions obtained by the \texttt{COMPASS} collaboration. We examine the impact of the \texttt{new COMPASS} proton and deuteron data on the polarized parton densities and compare with results from our previous study (KATAO PPDFs), which used the Jacobi polynomial approach. We find the extracted PPDFs of the proton, neutron, and deuteron structure functions are in very good agreement with the experimental data. The results for extracted PPDFs are also compared with available theoretical models from the literature., Comment: 16 Pages, 13 figures, 6 tables

Background: Helicobacter pylori infection is a major cause of gastric diseases in humans that its rapid, simple and low cost diagnosis is important. Diabetes mellitus increases the risk of Helicobacter pylori infection. Objective: The aim of this study was to compare diagnostic accuracy of serologic test with histology for Helicobacter Pylori in diabetic patients with dyspepsia. Methods: This analytical study was conducted on 183 diabetic patients with dyspepsia referred to Imam Hossain hospital of Shahroud in 2014. All patients underwent endoscopy. Standard biopsy was performed as gold standard which included six gastric and duodenal samples. Simultaneously, blood samples were taken for serologic test. The presence of Helicobacter pylori was examined using Giemsa staining in histological study. Anti-Helicobacter pylori IgG was measured using ELISA in serological study. Sensitivity, specificity, and positive and negative predictive values were calculated. Data were analyzed using Chi-square test. Findings: Of 183, 104 patients (57.1%) were positive for Helicobacter pylori in serological study and 151 patients (82.5%) were positive in histological study. The sensitivity, specificity, positive predictive value and negative predictive value of serologic test for diagnosis of Helicobacter pylori were 64.2%, 78.1%, 93.3%, and 31.6%, respectively. IgG cut point for diagnosis of Helicobacter pylori was set to be 1.4 (sensitivity: 92.4% and specificity: 75.3%). Conclusion: The serologic test can be used as screening test for Helicobacter pylori in diabetic patients with regards to relatively high sensitivity and specificity as well as its simplicity, rapidity, and low price.

The current study presents synthesis and characterization of high impact polystyrene - TiO2 nanoparticles mixed matrix membranes for separation of carbon dioxide from nitrogen. The solution-casting method was used for preparation of membranes. The nano mixed matrix membranes were characterized using scanning electron microscopy to ensure the suitable dispersion of nano particles in high impact polystyrene matrix. The effect of TiO2 nanoparticles loading on membrane performance was investigated. The separation performance of synthesized membranes was investigated in separation of CO2 from CO2/N2 mixture. Effect of feed pressure and TiO2 content on separation of CO2 was studied. The results revealed that increase of feed pressure decreases flux of gases through the mixed matrix membrane. The results also confirmed that the best separation performance can be obtained at TiO2 nanoparticles loading of 7 wt.%.

Hysteresis current control method is vastly used in PWM inverters because of simplicity in performance, fast control response and good ability in limiting peak current. However, switching frequency in hysteresis current control method with fixed bandwidth has large variation during a cycle and therefore causes non-optimal current ripple generation in output current. One of basic problems in implementing hysteresis current control is its variable switching frequency that causes sound noise and increase in inverter losses and also high frequency current components injection to the source current. In this paper, in addition to the calculation of variable hysteresis bandwidth equation that fixes frequency switching, also other problems can be solved by removing the derivative part. Here, a shunt active filter has been used for removing the current harmonic components generated by non-linear loads. Proposed method is simple to perform and reliable, and also has been simulated in MATHLAB software environment

In the present investigation, spherical nanoparticles of nickel ferrite with uniform structure were successfully produced by hydrothermal method in the presence of polyethylene glycol (PEG) as a polymeric surfactant at 180°C for 12 hour aging time and the effects of the synthesis time, temperature and surfactant were investigated. According to the X-ray analysis, conversion of nickel oxide and hematite to nickel ferrite was a way to produce NiFe2O4. At 140‌°C, agglomerated particles without specific shape were formed, but at 180°C particles were homogenous with spherical shape. Saturation magnetization increased by increasing the hydrothermal process aging time.

Failure mode and effect analysis (FMEA) model is a technique used to evaluate the risk. This paper aimed to propose a new FMEA model combining technique for order of preference by similarity to ideal solution (TOPSIS) and belief structure to overcome the shortcomings of the traditional index of FMEA. In this paper, the fuzzy belief TOPSIS method is combined with FMEA to introduce a belief structure FMEA to describe the expert knowledge by a number of linguists as a grammatical phenomenon. Moreover, the weights of components in FMEA index can be different from each other. Therefore, the flexibility of assigning weight to each factor in this method is more compatible to the real decision-making situation. In other word, TOPSIS method is applied to determine the preference of alternatives versus risk criteria. Using linguistic terms in the fuzzy belief approach, the risk factors described a more meaningful value and decision-makers’ judgment is assigned with belief degrees through evaluation of factors. Finally, a numerical case study about the preference of cause failures of steel production process is provided to illustrate the process of proposed method, and then result and discussion is performed for each case.

Single phase forced convective heat transfer and fluid flow of CuO/water and Al2O3/water nanofluids have been experimentally investigated in a microchannel heat sink (MCHS). The heat sink consisted of 17 rectangular cross section microchannels with the dimensions of 400 μm × 560 μm. All the experiments have been performed at constant heat flux of 19 W/cm2 and at the laminar flow regime 500

The purpose of this research was comparison of short-term, active and long- term memory between strong and weak students in Persian language dictation. Therefore, by cluster sampling, four girl’s elementary school among girls elementary schools in academic year 1392-93 in Chadegan city were chosen randomly. First, Persian dictation test of the students were sampled at three stages. Then dictation tests were marked and the average of each three tests for every student was calculated. 20 percent of high marks and 20 percent of low marks were chosen as strong and weak groups. Thirty students who earned highest marks (m=20)were chosen as strong group and thirty students who earned lowest marks were chosen as weak group (m=14/70). Both groups answered the questions of Wechsler memory test individually. For information analysis, independent–T-test and several changeable variance analyses were used. Findings of this research showed that the averages of strong students marks with average of weak students marks with average of weak students marks in Persian language dictation at long memory (general information subtests), active memory (mental control subtests),short hearing memory (logical memory subtests and repetition of figures) and over short visual memory and associative learning have meaningful difference (P

Many experimental observations have shown that in most nanostructures such as nanocomposites, carbon nanotubes (CNTs) are often characterized by a certain degree of waviness along their axial dimension. This geometrical imperfection has a profound effect on the mechanical behavior of CNTs. In the present work, the effects of initial curvature, shear deformation and influence of surrounding medium that are modeled as Winkler-Pasternak elastic foundation on behavior of slightly curved carbon nanotubes are investigated. It is shown that the initial curvature has an important role on mechanical behavior of curved carbon nanotubes. To capture the small size effects, nonlocal elasticity theory is implemented. Timoshenko beam theory (TBT) is used to model the behavior of CNTs and the governing equations are solved analytically. The effects of initial height and shear deformation on vibration frequencies and buckling loads are studied. It is found that these effects considerably contribute to mechanical behavior ...

SUMMARY In this paper, a biomechanical study of a human head model exposed to blast shock waves followed by a blunt impact with the surface of the enclosing walls of a confined space is carried out. Under blast, the head may experience primary blast injury (PBI) due to exposure to the shockwaves and tertiary blast injury (TeBI) due to a possible blunt impact. We examine the brain response data in a deformable finite element head model in terms of the inflicted stress/pressure, velocity, and acceleration on the brain for several blast scenarios with different intensities. The data will be compared for open space and confined spaces. Following the initial impact of the shock front in the confined space, one can see the fluctuations in biomechanical data due to wave reflections. Although the severity of the PBI and TeBI is dependent on the situation, for the cases studied here, PBI is considerably more pronounced than TeBI in confined spaces. Copyright © 2014 John Wiley & Sons, Ltd.

Objectives To evaluate anti-proliferative as well as apoptotic activities of compounds identified in chloroform extract of Juglans regia leaves, on human breast and oral cancer cell lines (MCF-7 and BHY). Materials and methods Column chromatography, MTT assay, flowcytometry and western blotting have all been used in the study. Results Bioassay-guided fractionation of chloroform extract of J. regia afforded isolation of 5-hydroxy-3,7,4′-trimethoxyflavone [1], lupeol [2], daucosterol [3], 4-hydroxy-α-tetralone [4], β-sitosterol [5], 5,7- dihydroxy-3,4′-dimethoxyflavone [6] and regiolone [7]. Structures of the compounds were established on the basis of spectroscopic analyses [Nuclear magnetic resonance (NMR) and mass]. All compounds inhibited proliferation of MCF-7 (human breast adenocarcinoma) and BHY (human oral squamous carcinoma) cells in a concentration-dependent manner. Compounds 6 and 7 had potent cytotoxic effects on both MCF-7 and BHY cells (IC50 21–51 μm), yet were not toxic to normal cells. MCF-7 growth inhibition was attributed to apoptosis; population of apoptotic cells increased from 1.12% in controls to 5.64 and 8.1% after 48-h treatment with compounds 6 and 7, indicating their potential at inducing early and late apoptosis. The caspase cascade was not activated, as indicated by only insignificant cleavage of caspase-3. Conclusions Our results suggest that compounds 6 and 7 can induce apoptosis in MCF-7 cells through the caspase-3 independent pathway.

In this paper, a computational modeling for biomechanical analysis of primary blast injuries is presented. The responses of the brain in terms of mechanical parameters under different blast spaces including open, semi-confined, and confined environments are studied. In the study, the effect of direct and indirect blast waves from the neighboring walls in the confined environments will be taken into consideration. A 50th percentile finite element head model is exposed to blast waves of different intensities. In the open space, the head experiences a sudden intracranial pressure (ICP) change, which vanishes in a matter of a few milliseconds. The situation is similar in semi-confined space, but in the confined space, the reflections from the walls will create a number of subsequent peaks in ICP with a longer duration. The analysis procedure is based on a simultaneous interaction simulation of the deformable head and its components with the blast wave propagations. It is concluded that compared with the open and semi-confined space settings, the walls in the confined space scenario enhance the risk of primary blast injuries considerably because of indirect blast waves transferring a larger amount of damaging energy to the head.

Introduction: interpersonal communication skills are required for training and represent one of the most significant parts concerning the character of student learning. In another idea, learning is a constant method and learners favor a position of knowledge forms according to their character and individual practices. Evaluate the correlation between the learning methods and interpersonal conversation abilities of the nursing undergraduate in Medical Sciences Tehran University in 2012 was the purpose of this research. Methods: In this regular detailed cross-sectional analysis, 361 students from the School of Nursing and Midwifery were chosen during a census method. The information collection instruments were regulated, giving a questionnaire called Interpersonal Communication Skills Standards exam and VARK Learning Styles questionnaire. Data was examined by SPSS application (18th edition) by using Mann-Whitney and Kruskal-Wallis test. Results: 320 questionnaires were finished. 60.6% of the members were females. The average number of the students’ conversation abilities level was 101.91 ± 10.35. More than half of the samples (58.8%) preferred multi-modal learning styles (Bi-Tri and Quad Modals) and 41.2% of the students preferred single modal learning styles. There were no significant differences between the Interpersonal Communication Skills and the learning styles (P= 0.46). Conclusion: According to no significant relationship between the communication skills of students with learning style and Demographic changeable and Lack of proper form of communication skills, we were ready to build different systems and courses related to improving the skills’ level.

Background: As the biggest collection among various collections of hospital employees, nurses perform a vital role in the progress of the hospital actions and the improvement of community health. Objectives: This research intended to find the relationship between the shortage of nursing workforce and hospitals performance of Tehran’s Medical Sciences University. Materials and Methods: The current analysis was a cross-sectional definitive research, which was conducted in selected educational hospices associated to Tehran University of Medical Sciences during the year 2010. While using three researcher-made questionnaires, information was obtained from all clinical, paraclinical, commercial, managerial and support units of hospitals. Information was investigated according to the patterns of Iran's Healthcare Ministry and Medical Education by employing Excel software. Pabon Lasso model was used for performance measurement during the year 2010. The mixture of 3 indicators was applied to determine the period of stay, bed occupancy time and bed turnover. Results: The outcomes revealed that the personnel of nursing, in the 18 hospital wards (66.67%) were at levels below the standards, just one ward (3.7%) reached the standards requirements, and the remainder of the hospital wards (29.62%) were at greater levels than the standard requirements. Both hospitals were near the value 4 in the Pabon Lasso model. The correlation analysis among the nursing shortage and performance showed a meaningful relationship (P

We study the polarized parton distribution functions (PPDFs) from recent experimental data at the next-to-leading order (NLO) approximation in the fixed-flavor number scheme. In this analysis, we can compare our results with experimental data such as very recent COMPASS data. It would be very worth to study the PPDFs parametrization form when we want to use this new COMPASS data in QCD analysis on polarized proton structure and parton distribution functions.

Vibro-acoustic techniques have been developed with the aim of determining the location of buried pipes. However, the characteristics of the recorded conical wave radiation from the pipe wall to the surface, at very low frequencies, have not been investigated in depth.

This study was conducted to determine whether two estrus phases (proestrus and diestrus) in female rats may influence the metabolic response to a high-fat diet and/or stress, focusing on pancreatic insulin secretion and content. Animals were divided into high-fat and normal diet groups, then each group was subdivided into stress and non-stress groups, and finally, each one of these was divided into proestrus and diestrus subgroups. At the end of high-fat diet treatment, foot-shock stress was applied to the animals. Then, blood samples were taken to measure plasma factors. Finally, the pancreas was removed for determination of glucose transporter 2 (GLUT2) protein levels and assessment of insulin content and secretion of the isolated islets. In the normal and high-fat diet groups, stress increased plasma corticosterone concentration in both phases. In both study phases, high-fat diet consumption decreased estradiol and increased leptin plasma levels. In the high-fat diet group in response to high glucose concentration, a reduction in insulin secretion was observed in the proestrus phase compared with the same phase in the normal diet group in the presence and absence of stress. Also, high-fat diet decreased the insulin content of islets in the proestrus phase compared with the normal diet. High-fat diet and/or stress caused a reduction in islet GLUT2 protein levels in both phases. In conclusion, it seems possible that high-fat diet alone or combined with foot-shock, predispose female rats to impaired insulin secretion, at least in part, by interfering with estradiol levels in the proestrus phase and decreasing pancreatic GLUT2 protein levels.

The influence of tortuosity and fluid volume fractions on trickle-flow bed performance was analyzed. Hydrodynamics of the gas-liquid downward flow through trickle beds, filled with industrial trilobe catalysts, were investigated experimentally and numerically. The pressure drop and liquid holdup were measured at different gas and liquid velocities and in two different loading methods, namely, sock and dense catalyst loading. The effect of sharp corners on hydrodynamic parameters was considered in a bed with rectangular cross section. The reactor was simulated, considering a three-phase model, appropriate porosity function, and interfacial forces based on the Eulerian-Eulerian approach. Computational fluid dynamics (CFD) simulation results for pressure drop and liquid holdup agreed well with experimental data. Finally, the velocity distribution in two types of loading and the effect of bed geometry in CFD results demonstrated that pressure drop and liquid holdup were reduced compared to a cylindrical one due to high voidage at sharp corners.

The nonlinear free vibration of nanobeams with considering surface effects (surface elasticity, tension and density) is studied using Euler–Bernoulli beam theory including the von karman geometric nonlinearity. The component of plane stress, σ zz , is assumed to vary linearly through the beam thickness and satisfy the balance conditions between nanobeam bulk and its surfaces. Accordingly, surface density is introduced into the governing equation of the nonlinear free vibration of nanobeams. It is seen that the effect of surface density is independent of amplitude ratio. In addition, it is observed that in lower modes, surface density has insignificant effects on the variation of the natural frequency versus mode number, whereas this is not the case in higher modes where the surface density causes the normalized natural frequencies of the nanobeams to increase drastically. Moreover, it is shown that the effect of the surface density on the variation of the natural frequency of the nanobeam versus the thickness ratio decreases consistently with the increase of the mode number.

Background and Aim: Identifying criteria of expert teacher and efforts to strengthen and use them in teaching by teachers will enhance the learning process. In this way, one of the important methods is taking the views of students. This study was conducted to determine the characteristics of an expert teacher for effective teaching from the viewpoints of allied medical students at Tehran University of Medical Science. Materials and Methods: In this cross-sectional study, 200 BSc of allied medical students at were included employing simple random sampling method. Data collection was done employing a self administrated questionnaire. Validity and reliability of questionnaire was calculated. Data analysis was carried out by t-test and SPSS software. Results: Some criterias like dominance in the scientific subjects (86.8%), power of expression and transmission the training materials (86.2%), respect for students(85.6%), good mood(85%) and work with ethic and sense of responsibility (84.4%) are important criteria for expert teacher. Furthermore, no significant relationship was found between gender and field of study and the above-mentioned four domains (p> 0/05). Conclusion: Teaching ability was the most important factor for teaching process from he view of the students which could be paid attecntion in teachers' assessment program.

Introduction: In the universities and academic institutes, most of the research activities are performed in departments and research centers, which are evaluated by measurement of indices such as number of academics and students, number of publications and patents, citation analysis, journals in which their reports have been published, the amount of grants etc. Methods: Academic department is considered as the evaluation unit of researcher’s activities. Two important parameters of departments’ “research focus” and number of academics who are active in the “field of focus” have not been considered in any evaluation systems yet. Results: In this article, two new indices entitled “subject h-index” (hs-index) and “researcher for subject h-index” (hrs-index) are proposed for measurement of these parameters. Conclusion: Both of suggested indices make the assessing and monitoring of research focus and active scientists feasible.

"nWe report a case of human urogenital myiasis in an 86-year-old rural man with a penil ulcer and numerous alive and motile larvae from urethra and glans penis. Entomological studies on adult flies showed the larvae were Lucilia sericata and Wohlfahrtia magnifica. The clinical presentation and treatment strategies are discussed.

Geography be one way the creation of 21st century skills, where geography can help students develop global awareness and allows them to be creative and innovative. Seeing these benefits, presumably prospective teachers can master the material and learning geography in order to guide students toward global awareness. This case study was carried out to the students of primary school teacher candidates with questionnaires and interview techniques. The results showed that the students' perspective on the material of geography is a branch of social science that studies the environment and its relationship with humans. While the student perspective on learning geography is the interaction between students and teachers in order to understand the material geography.