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Abstract Gabion weirs are environment-friendly structures widely used for irrigation and drainage network purposes. These structures' hydraulic performance is fundamentally different from solid weirs' due to their porosity and the existence of a through-flow discharge. This paper investigates the reliability and suitability of a number of Machine learning models for estimation of hydraulic performance of gabion weirs. Generally, three different Boosting ensemble models, including Gradient Boosting, XGBoost, and CatBoost, are compared to the well-known Random Forest and a Stacked Regression model, with respect to their accuracy in prediction of the discharge coefficient and through-flow discharge ratio of gabion weirs in free flow conditions. The Bayesian optimization approach is used to fine-tune model hyper-parameters automatically. Recursive feature elimination analysis is also performed to find optimum combination of features for each model. Results indicate that the CatBoost model has outperformed other models in terms of estimating the through flow discharge ratio (Q in /Q t ) with R 2 = 0.982, while both XGBoost and CatBoost models have shown close performance in terms of estimating the discharge coefficient (C d ) with R 2 of CatBoost equal to 0.994 and R 2 of XGBoost equal to 0.992. Weakest results were also produced by Decision tree regressor with R 2 = 0.821 and 0.865 for estimation of C d and Qin/Qt values.

Predicting the behaviour of wildfires can help save lives and reduce health, socioeconomic, and environmental impacts. Because wildfire behaviour is highly dependent on fuel type and distribution, their accurate estimation is paramount for accurate prediction of the fire propagation dynamics. This paper studies the effect of combining automated hyperparameter tuning with Bayesian optimisation and recursive feature elimination on the accuracy of three boosting (AdaB, XGB, CatB), two bagging (Random Forest, Extremely Randomised Trees), and three stacking ensemble models with respect to their ability to estimate the vegetation cover type from cartographic data. The models are trained on the University of California Irvine (UCI) cover type dataset using five-fold cross-validation. Feature importance scores are calculated and used in recursive feature elimination analysis to study the sensitivity of model accuracy to the different feature combinations. Our results indicate that the implemented fine-tuning procedure significantly affects the accuracy of all models investigated, with XGB achieving an overall accuracy of 97.1% slightly outperforming the others.

Abstract The present article seeks to explore the sociological factors and consequences of social demand for the PhD in the recent decade in Iran. The method used is qualitative and within the framework of phenomenology .First, by the use of documentary method, empirical and theoretical backgrounds of the research were investigated, then these factors and consequences were put in a focus group interview with 10 experts and higher education officials. Finally, the findings of the research were classified in two parts: sociological factors and sociological consequences of social demand for the PhD degree. The factors of social demand in general became: "individual-family factors" and "environmental factors". Family factors include customs and morals and individual factors include the value of belonging, intrinsic value, functional value, and the exchange value of pursuing a doctoral degree. Environmental factors include historical, institutional, economic, and socio-cultural factors. The consequences of this phenomenon include scientific-educational, socio-cultural and economic consequences, which were divided into positive and negative categories. Finally, regarding extracted factors, some solutions to the problem of high social demand for higher education were suggested. Keywords Education Continuation, Sociological Consequences, Social Demand, Ph.D, Sociological Factors.

A comprehensive understanding of the sediment behavior at the entrance of diversion channels requires complete knowledge of three-dimensional (3D) flow behavior around such structures. Dikes and submerged vanes are typical structures used to control sediment entrainment in the diversion channel. In this study, a 3D computational fluid dynamic (CFD) code was calibrated with experimental data and used to evaluate flow patterns, the diversion ratio of discharge, the strength of secondary flow, and dimensions of the vortex inside the channel in various dike and submerged vane installation scenarios. Results show that the diversion ratio of discharge in the diversion channel is dependent on the width of the flow separation plate in the main channel. A dike perpendicular to the flow with a narrowing ratio of 0.20 doubles the ratio of diverted discharge in addition to reducing suspended sediment input to the basin, compared with a no-dike situation, by creating the outer arch conditions. A further increase in the narrowing ratio decreases the diverted discharge. In addition, increasing the longitudinal distance between consecutive vanes (Ls) increases the velocity gradient between the vanes and leads to a more severe erosion of the bed, near the vanes.

Background: Despite our awareness of the significant effect of Social Determinant of Health (SDoH) such as Socio Economic Status (SES), income and education on breast cancer survival, there was a serious lack of information about the effect of different level of these factors on breast cancer survival. So far, no meta-analysis has been conducted with this aim, but this gap was addressed by this meta-analysis. Methods: Main electronic databases such as PubMed, Web of Science, and Scopus were investigated up to January 2019. Epidemiological studies focusing on the association between SDoH and breast cancer were singled out. Q-test and I2 statistic were used to study the heterogeneity across studies. Begg's and Egger's tests were applied to explore the likelihood of the publication bias. The results were reported as hazard ratio (HR) with 95% confidence intervals (CI) through a random-effects model. Results: We identified 7,653 references and included 25 studies involving 1,497,881 participants. The HR estimate of breast cancer survival was 0.82 (0.67, 0.98) among high level of SES, 0.82 (0.70, 0.94) among high level of income and 0.72 (0.66, 0.78) among academic level of education. Conclusions: The SES, income, and education were associated with breast cancer survival, although the association was not very strong. However, there was a significant association between the levels of these factors and breast cancer survival.

سلامت اجتماعی مفهومی نسبتاً جدید در مباحث، نظرات و مطالعات اجتماعی است. این مفهوم همبعد نظری وهم کاربردی تجربی و میدانی دارد. یکی از حوزههایی که هم در سطح جهانی وهم درسطح ایران محل طرح و بهکارگیری سلامت اجتماعی بوده و هست، حوزه آموزش و بالطبع قلمروپژوهشهای آموزشی است. مطالعه دیگری نشان داده است که بهطورکلی ادبیات ایرانی این قلمرو چهدر بعد نظری و جه در بعد کاربردی ضعیف ولی رو به رشد است. مطالعه حاضر در پی ارزیابیوضعیت طرح این مفهوم بهطور مقایسهای در مجلات علمی پژوهشهای آموزشی داخل و خارج ازکشور و بهعنوان نمونه سه مجله مطرح در این قلمرو از ایران، مالزی و آمریکا بوده است. چنانکه دراین مقاله خواهیم دید، پوشش سلامت اجتماعی در کل و نیز به لحاظ محورها و مؤلفهها در مجلهایرانی کمتر از دوتای دیگر است.

Background: Health literacy is a major factor for health promotion and well-being. In spite of several researches on health literacy, information on the subject of the status of health literacy in Asian countries such as Iran is inadequate. Therefore, this study aimed to assess the inequality of health literacy in an Iranian population and its influencing factors. Methods: In this cross-sectional study, 736 families were selected by cluster random sampling. A validated questionnaire was used to measure the health literacy of participants. Socioeconomic status (SES) was calculated by asset-based approach, and principal component analysis (PCA) was performed to estimate the families' SES. Concentration index and curve were used to measure SES inequality in health literacy, and after that decomposed into its determinants. The data were analyzed by Stata software. Results: The mean age of the participants was 34.81 years (standard deviation = 5.98 years). The value of concentration index for health literacy equals 0.2292 (95% confidence interval = 0.168–0.283), and this value indicates that there is inequality in distribution of health literacy in Iran and the inequality disfavors the poor. Conclusions: The results of this study revealed that there is inequality in distribution of health literacy in Iran, and people of higher economic status in Iran enjoy from better health literacy levels.

سلامت اجتماعی از مفاهیم جدید مطرح در علوم اجتماعی است که در یکی دو دهۀ اخیر در ایران وجهان مورد توجه قرار گرفته است. بسیاری از صاحبنظران مطالعات اجتماعی بر این باورند که نوعیجمع بندی از شرایط اجتماعی جامعه در ذیل ابعاد مختلف این مفهومِ نوپا، مستتر است ، و به جهتگستردگی میتواند شاخص و ابزار تحلیلی خوبی برای جامعه شناسان، آسیب شناسان اجتماعی وبرنامه ریزان باشد. از سوی دیگر نظام آموزشی زیرسیستم مهمی از هر جامعه است که هم پوشش دهندهبعضی از شاخصهای سلامت اجتماعی است، هم مرتبط با شاخصهای دیگری از آن است، و هممحور تربیت نیروی انسانی است و بخش مهمی از کم و کیف فرایند اجتماعی شدن نسلهای جدید راشکل می دهد. در ایران معاصر نظام آموزشی دستخوش تحولات زیادی شده است و امروز هم چنانضرورت بازنگری در بخشهای مرتبط با امر آموزش و پرورش که شامل آموزش ر سمی، آموزشعالی، ضمن خدمت، علمی کاربردی میباشد، احساس می گردد. در این پژوهش، با روش فراتحلیل،تحقیقات و تألیفاتی که به طور توأمان در رابطه با نظام آموزشی و مؤلفه های سلامت اجتماعی هستند،مورد بررسی قرار گرفته اند. فراتحلیل از روشهای کیفی تحقیق رایج در علوم مختلف است که درعصر تورم دانش و اطلاعات، ضرورت و رونق ویژه ای پیدا کرده است . فراتحلیل از یک سو بهجمع بندی و پیوند تحقیقات انجام شده و از طرف دیگر به ماحصل کاربردی آن ها م یپردازد و درترسیم نگرش جامع و ارائه پیشنهاد به برنامه ریزان کاربرد منحصر به فردی دارد. نظر به ضرورتبررسی و ارزیابی تحقیقات و تألیفات آموزشی انجام شده در حوزه سلامت اجتماعی در ایران، در اینپژوهش با استفاده از مجموعه مؤلفهها و شاخصهای سلامت اجتماعی که از تحقیقی پیشین به دستآمده، فراتحلیل سلامت اجتماعی در پژوهشهای آموزشی صورت گرفته و نتایج آن بیان شده است.

Background and aim: The present research aims to draw and analyze the scientific collaboration network in the field of cultural heritage protection based on the data retrieved from the AATA database from 1800 to 2020. Materials and methods: This is a descriptive and applied research which was conducted with a scientometric approach. The research community includes all articles indexed in the AATA database from 1800 to 2020. Articles were reviewed in terms of micro and macro network parameters. Vosviewer, Microsoft Excel, Ucinet and Ravar PreMap were used to analyze the research data. Findings: The mean growth rate of articles is 14.12% and the doubling time of studies is 4.96 years. The mean growth rate of authors is 16.97% and the doubling time of researchers is 4.12 years. Based on macro network parameters, network density is 0.001, network cohesion is 0.186 and network diameter is 24. Single-author researches are decreasing and the collaboration of authors in researches is increasing. Collaboration index, collaboration degree and collaboration coefficient have increased and reached 3.93, 0.79 and 0.57, respectively, in 2020. Conclusion: Examining the macro parameters of the co-authorship network in this field shows the low cohesion of the authorship network and according to the values ​​of network diameter and the average distance, the distribution of information in this network is unfavorable, and chemistry researchers with high betweenness centrality have more influence than other researchers in the field of cultural heritage protection.

Abstract Various Flexible Alternating Current Transmission System (FACTS) devices are used to improve the power quality and reliability of power system. In addition to the technical constraints, the installation and maintenance costs limit the exploitation of such devices. To maximize the efficiency of FACTS, the least possible number of devices must be placed optimally in the network. In this vein, many types of research have been conducted to offer optimal placement solutions. Although these methods lead to optimal placement, they usually suffer from a huge amount of computational burden. Therefore, here, an intelligent optimal placement approach is presented, focusing on reducing computational volume. For this aim in the suggested method, the monitoring buses are limited, while monitoring other buses is carried out using an estimation approach. To avoid increasing calculations for this selection, applying the worst fault condition instead of all fault types, the least number of monitoring buses are selected. Moreover, high‐risk zones are indicated for each monitoring bus so that by applying different fault conditions in only these areas, the study is conducted, which results in an additional decrement in computational burden. Finally, the optimal placement problem is solved by employing the genetic algorithm.

Abstract This article suggests a non‐isolated high step‐up interleaved DC–DC topology for renewable energy applications. Two three‐winding coupled‐inductors along with two voltage multiplier cells are used to enhance the voltage gain significantly. One interesting aspect of this new topology is that high duty cycles are not required to achieve high voltage gains; this is done by adjusting the turn ratio of the coupled inductors. Moreover, the presented interleaved converter enjoys not only having less current stress due to the interleaving structure, but also showing 16% increase in voltage gain compared to the best similar boost topologies. Additional elements are designed for the purpose of soft switching and gain increase, which have little effect on the cost, weight and size of the proposed converter. Interestingly, the voltage stresses both on the switching devices and passive elements are much less than the output voltage. Furthermore, the coupled inductor's leakage inductance energy is recovered by employing a passive clamp circuit to minimize stresses across the semiconductors; therefore, efficiency is improved. The suggested converter is analyzed in the steady state, and a 400 W experimental setup was implemented; the outcomes verify the practicality of the proposed boost converter in accordance with the analysis.

The need for high gain DC-DC converters has lately increased in tandem with the utilization of renewable energy supplies. Particularly appealing are high gain converters that do not require the inclusion of extra power switches and/or other passive elements to the system. As a result, this study proposes a non-isolated single switch converter with ultra-high voltage gain (UHG) that is appropriate for most renewable energy conversion systems, like solar installations. With only a single MOSFET working within a suitable duty cycle region, the proposed converter provides significant voltage gain and around 95% efficiency. Moreover, the MOSFET in this UHG converter is turned on in zero current switching (ZCS) mode, resolving the diode recovery issue. The recommended UHG converter’s working modes, steady-state parametric study, circuit variables like voltage stress on switching devices, and converter gain are all thoroughly explained. Comparisons have been done with comparable topologies presented in the literature, and lastly, experimental results depending on 200W (20V input, 320V output voltage) are given to validate the operation of the proposed UHG design.

This research aims to verify the patterns of users' tagging to the articles of knowledge and information science field in academia.edu. The research method is quantitative and based on text mining and applicable typically. The population includes 6086 bibliographic articles and their abstracts extracted from 159 English journals of knowledge and information science field in Scopus database that are core journals in LISTA as well. In order to gather these data, 194337 articles were searched in academia.edu then every article that tagged was chosen. Examining the relationship between the growth of different types of tags (one-word, two-word, three-word, and four-word and more) and increasing of documents showed a linear correlation between them. Among the different groups of tags, the highest growth rate was related to two-word tags (.609%) and the lowest growth rate was related to four-word tags and more (.143%). The total growth rate of the tags (new and duplicate) was also 5.52 (i.e. 5.52 tags per document). It was also found that two-word tags had the most matching (54.92%) and four-word tags and the least matching (1.76%) with different sections of articles (title, abstract, and authors' keywords). The total tags were matched 7.5% with the title, 76.61% with the abstract, and 15.89% with the authors' keywords. Regarding the reuse of tags, it was revealed that in general, 38.8% of the tags have been reused. On the other hand, two-word tags with 57.59% had the most reuse and four-word tags and more with 7.54% had the least. Another point is that 16% of the tags were reused in the first year and more than 50% of the tags were reused in the first 3 years. Finally, it can be said that the existence of a significant user consensus on certain terms indicates that the new patterns of user tags are at least partially compatible with professional indexing concepts about document content, and by focusing on the most widely used tags and their sustainable distribution, weight formulation and even classification schemes may be achieved. Also, users' activities on social networks can be used to increase the quality of suggestions in collective tagging systems. Another point is that there is a connection between professional indexing and user tagging, and the two are not alien to each other. This connectivity can be the basis for a complementary subject access system that enriches professional indexing.

Abstract Modelling the uncertainty of wind speed is essential in power flow analysis. Having abundant knowledge of the wind speed in an area is critical. A low volume of data can increase uncertainty in wind speed analysis. Spatial dependencies are often modelled before running probabilistic power flow and load flow analysis. Copulas are a popular way of capturing spatial dependence between multiple wind farms. Using NREL data from seven Northeastern United States wind farm sites, Bayesian inference will be used to determine the copula parameter uncertainty between weekly, daily, and hourly wind speed observations. This approach will be used on elliptical and single parameter Archimedean copulas. For each possible wind farm pair, an uninformative prior will be placed on the copula parameter. The resulting posterior will contain a distribution of copula parameter values based on the prior and the observed wind speed data. The posterior's credible interval is reviewed to determine the uncertainty in parameter estimation. The results show that using a data volume considerably more petite than 8760 hourly data points will result in more uncertainty in parameter estimation and inaccuracies in wind speed forecasting if using non‐Bayesian methods for copula parameter estimation.

During the recent years, gabion weirs have attracted the attention of many researchers due to their compatibility with the environment, positive effects on river's water quality and simple design and implementation. In this research, the hydraulic parameters of flow around the triangular and broad-crested gabion weirs with various side slopes were numerically investigated. The numerical results were validated using the data obtained from laboratory experiments. Overall, a number of 256 different models were studied numerically. Results indicated that decreasing the average diameter of particles may result in the reduction of the discharge coefficient (C d ), through flow discharge and the energy dissipation of flow over the models up to 27%, 34%, and 8% respectively. Also, it was concluded that the upstream slope of triangular weirs and downstream slope of broad-crested gabion weirs have more significant impact on the performance of gabion weirs. Finally, mathematical relationships are correlated using Nonlinear Multivariate regression analysis in order to estimate the discharge coefficient and through flow discharge of these structures. [ABSTRACT FROM AUTHOR]

Background and aim: Assessing the quality of scientific outputs is part of the development measuring system of countries around the world. The aim of this study was to analyze the thematic structure of the top articles of Iranian researchers in the Web of Science (WoS) database in Web of Science database. Materials and methods: This applied-descriptive study was performed using scientometric method. The research population was all top papers of Iranian researchers indexed in Essential Scientific Indicators (ESI) and WoS databases from 2010 to 2019. Data were analyzed using Ravar Matrix and Ucinet softwares. Findings: Total number of Iranian top articles was 2447 of which 2428 and 114 were highly cited and hot articles published from 2010-2019, respectively. The top ranking of centrality was assigned to the keyword "nanofluid" with a closeness centrality of 53.684, betweenness centrality of 24.229 and degree centrality of 3.020%. Conclusion: The top articles of Iranian researchers were classified into 14 thematic clusters, so that most of these articles were in the field of "engineering" and the keyword "nano" was the most important thematic keyword and the basic foundation of this study.

Subject and Purpose of the Article: This research studied external accountability gap of tax affairs organization from the viewpoint of academic society, great taxpayers and the government through applying Servqula model. Research Method: Statistical society includes faculty members, CFOs and governmental experts which 156 samples of these three stakeholders were selected by sampling method and questionnaire distributed among them. Dependent t-test for paired samples and one way-analysis of variance test were utilized to test the hypotheses. Research Findings: Results show that there is a deeper gap in external and ethical accountability of National Tax organization from faculty members and CFOs' viewpoints. Besides, there is a deeper gap in financial, performance, democratic and political accountability from faculty members viewpoints in compare with two other strata. Conclusion, Originality and its Contribution to the Knowledge: Thus, tax affairs organization must fill the external gap toward academic society and major taxpayers and on the other hand does its best to improve accountability condition of the Organization.

An accurate and real-time knowledge of temperatures in insulated-gate bipolar transistor modules is crucial for reliability analysis and thermal management of power electronic converters. For this purpose, this paper establishes an integrated thermal equivalent circuit model comprising self-heating thermal impedances and cross-heating thermal impedances to provide a temperature profile of the junction and solder joints during various operations and in the case of thermal aging. The thermal resistance and capacitance parameters of the thermal impedances are characterized in terms of different electro-thermal operating conditions and solder joints aging conditions with the help of three-dimensional finite element simulations. Also, the effect of the heatsink, which brings an uneven heat transfer coefficient distribution at the module baseplate, is investigated and modeled into the thermal impedances. The introduced thermal model can work even if the conditions change simultaneously. The accuracy of the model is verified by experiments and finite element simulations, all of which agree with negligible error unlike thermal models given in the datasheet and fixed-parameter thermal models.

Sassanid reliefs are somehow reflecting events that include part of the beliefs, wars and victory over enemies, family relationships and courtesy, hunting and getting diadem. In the meantime, the reliefs of victory, which created a very positive psychological aspect among the society and the people, have received more attention from the kings. There has been a lot of research on Sassanid reliefs so far and many researchers have studied various dimensions of these reliefs. In the meantime, the reliefs of Shapur I, whose victories over the three Roman empires, namely Gordian III, Philip and Valerian, have been depicted, will be analyzed and examined. Sassanid Shapur I defeated Gordianus at the Battle of Mesica in 244 B.C. The narrations have informed that this emperor was killed on the battlefield. After this event, Philip paid a heavy annual tribute to the court of the Sassanid king and asked to support him to sit on the throne until the end of the war. About 15 years later, another Roman emperor named Valerian campaigned Iran that he was also captured by Iranians in Mesica with 70,000 Roman soldiers. Shapur ordered to sculpt these victories in Darabgird, Bishabour and the Naqsh-e Rustam, symbolically on the heart of the rocks. Scholars, however, have almost no doubt about the attribution of the present people in Shapur's reliefs to the three Roman empires, but it seems that the third Shapur’s relief in Tang-e-Chogan reminds another kind of narrative. The body of Gordianus in two reliefs in Bishabour and the relief of Darabgard, is slightly different from the relief number 3 in Bishabour, which is severely eroded and damaged. Regarding the location of this relief in an unsuitable place and its lower quality with other Shapur reliefs, it seems that it was carved in a hurry. The reason may be the events that took place between 260 and 267. After the capture of Valerian, the Roman court made many efforts to free him but never succeeded. In the same years, Odaenathus, the Arab Amir of Palmyr, had been involved with the Iranian army several times and had succeeded in defeating, supported by the Romans. Odaenathus was titled August by the Roman court for his great victories and was publicly called emperor. The growing power of this Palmyrian’s Amir caused concerns within the Sassanid court. The vastness of his territory itself indicates the power of the Palmyrians during these years. But the sudden and mysterious death of Odaenathus by the hands of his son and wife Zenobia reinforces the conspiracy theory of the Iranian court with Odaenathus's wife and son to eliminate this Arab Amir. According to the body covering and makeup of the person’s face depicted under the foot of Shapur’s horse in the relief of number 1 of Bishabour and its difference with the reliefs in which Gordianus is depicted, it can be hypothesized that this role is a reflection of the events between 260 and 267. Shapur portrays this relief as a general victory over the Roman emperor and court for their conspiracy and evils and the overthrow and elimination of Odaenathus, who was supported by the Romans. In the present article, we have attempted to analyze and study the reliefs of the victory of Shapur III over the Roman emperors with a descriptive and an analytical method and comparing the reliefs along with the use of numismatics. This analysis along with historical narratives can give the viewer a better view to look at these reliefs.

The present survey aims to study the scientific texts and social texts linked each other by citations in order to investigate the influence of scientific terms on social texts. The social text is expected to be a bridge between scholars and users by citing scientific texts. By indexing scientific and social text and measuring its similarity by means of an inclusion index, it is possible to see the influence of scientific terms on social texts. The basis of the statistical data of the present study is the scientific papers on climate change issues published in the journals covered by the Web of Science, which have the role of the research community. Sample members consisted of 9876 scientific and social texts (7912 social texts cited 1964 scientific texts) that were extracted and stored in .txt files with the help of Python web scraping using beautiful soup package. The pdf files were extracted manually and converted to a txt file. The indexed terms of the scientific and social texts and the common terms between them, were identified and categorized according to their length and document types separately using the automatic negative indexing model and regular expressions. Measuring the penetration of scientific terms on social texts using the inclusion index, showed that the average penetration rate was 27%. There was a positive, significant and strong correlation (0.76) between the number of common terms and academic penetration. The results of chi-square test showed that there is a significant relationship at 1% level between the term length and the average penetration rate. There is also a difference between the level of penetration and the type of social documents type, including news, blogs, policy documents, Wikipedia, and peer reviews. The highest percentage of penetration is related to policy documents and then Wikipedia. Obtaining 22 citations and 40 social citations on average per paper, and the strong correlation between citation and altmetric score, indicates the citation influence among the academic and non-academic community. Collectively, with the power of altmetrics like policy documents, Wikipedia and blogs and their permeability, they can be used to further promote scientific findings. Publishing scientific findings in these sources, even in a different language from scientific authors, can contributed to greater awareness of society and the general public.

A high voltage direct current system based on the modular multi‐level converter (MMC‐HVDC) is introduced as a suitable device for transmission of bulk powers over long distances. A pole‐to‐pole DC‐side fault is a significant challenge for the MMC‐HVDC system. Three main problems are the appearance of voltage spikes following a fast DC fault current break up, frequency instability due to insufficient inertia (networks such as renewable energy‐based systems) and destruction of anti‐parallel diodes within the MMC due to the high fault current. This study proposes a novel method for limiting DC fault current, improving isolation of the three‐phase AC system from the DC‐side. The suggested design employs high power resistors as virtual load such that continuity in active power flow will be kept on. Further, this prevents frequency deviation from exceeding the allowable limits. Also, transient over‐voltages will be limited which are coming from stray inductances linked with electromagnetic effects of fault current level. Simulations and design practical issues have verified the validity of the proposal by using MATLAB/Simulink.

Background: The purpose of this study was to compare the effect of magnesium sulfate adjunct to dexmedetomidine on increasing the duration of sensory and motor block in axillary block. Materials and methods: This study is a double-blind clinical trial. Ninety-nine patients were included in the study. They were undergoing forearm and hand surgery and were referred to Vali-e-Asr Hospital in Arak. The patients were divided into three groups. The first group received lidocaine (1.5%) and dexmedetomidine (0.5 μg/kg). The second group patients were given lidocaine (1.5%) plus magnesium. In the control group, lidocaine (1.5%) was adjusted to 35 cc with normal saline. The final volume was 35 cc in the three groups. Sensory and motor block and pain were measured and data were analyzed using SPSS v. 20. The final volume was 35 cc in the three groups. Results: The sensory and motor block onset time and the stabilization time of the sensory and motor block in the magnesium sulfate group were lower (p

Introduction: Axillary brachial plexus block is used for anesthesia in hands and forearm surgery. The aim of this study was to compare the hemodynamic changes of magnesium sulfate and dexmedetomidine in axillary block. Materials and Methods: This randomized, double-blind clinical trial was conducted on 99 patients undergoing a forearm and hand surgery at the Vali-Asr Hospital. Patients were divided into three groups. Dexmedetomidine group consisted of lidocaine 1.5% plus 0.5 μg/kg dexmedetomidine, magnesium sulfate group included lidocaine 1.5% plus 100 mg magnesium sulfate, and the control group received lidocaine 1.5% with normal saline. The final volume was divided into 35 groups in three groups. Blood pressure, heart rate, and oxygen saturation were measured every 5 minutes during surgery, and data were analyzed by SPSS 23. Results: There was a statistically significant difference between the three groups in terms of the mean blood pressure during surgery (P < 0.05). At all times, blood pressure in the dexmedetomidine group was lower as compared to the other two groups. But in the 20th and 25th minutes, there was a relative increase in blood pressure. There was a significant difference between the three groups in terms of heart rate during surgery in minutes 20, 25, 65–100, and 110–120 (P < 0.05). Conclusion: The final result showed that the blood pressure and heart rate of the dexmedetomidine group patients at different times were less than the other two groups.

Introduction: One problem in conducting scientometric thematic analysis is selecting which of the bibliographic fields containing the topics can be analyzed. This study aimed to compare subject fields of documents to determine the field or a combination of fields which are suitable for conducting a complete and proper thematic analysis in scientometrics. Methods: This was a descriptive research with content analysis approach. Scientific products in the field of functional gastrointestinal disorders were extracted from the Scopus database. The analysis was done on 13798 documents, which included title, author keywords, and index keywords. After clustering using the K-Means method, and calculating the inclusion index for created clusters, the similarity of keywords between the three fields was determined. Results: There was a high similarity between the index and the author keywords (87.71 and 85.71). The low amount of the index in the title field and the index keywords (0) also suggested that there was little similarity between the controlled vocabulary and the keywords used by the authors in the title, and that authors did not use the preferred vocabulary in the title. Conclusion: Using the words of the title field will show the results of the natural language analysis. However, if the purpose of a study is categorizing terms, the use of index keywords field will be the most appropriate.

Introduction: The relationship between science and technology is of evolving and changing type, and it might vary from discipline to discipline and from time to time. Therefore, this study aimed to investigate and explain the relationship between the science and technology in dental implants field. Methods: This study was implemented through content analysis, using co-word analysis approach. The database on the United States Patent and Trademark Office was used to retrieve patents, while the PubMed was used to retrieve the papers in dental implants field. In total, 1479 papers as well as 433 patents were studied. The phrase "dental implants" was searched as a Mesh descriptor, and the document type was filtered by "clinical trial". Results: Assessment of the asymmetric similarity of the phrases used in clinical trial with patents and vice versa revealed that 39.15% of the terms used in patents were also used in these papers. In other words, 39.15% of the terms of patents were similar to the ones used in papers of clinical trial. This was while only 5.31% of the terms in these papers were the same terms used in patent papers. Conclusion: The accessibility of a document will increase its application and its visibility. In other words, it can be inferred that technology is affected by science. In general, in dental implants field, the path to science and technology is interconnected, and there is a direct relationship between them; however this is a two-way relationship, but technology has more influence on science.

Background: Dental implants are known as a widely accepted and predictable method to replace missing teeth. Many factors, including using a class of drugs, such as β-blockers, can improve the osseointegration of dental implants. This study aimed to investigate the relationship between administrating propranolol and osseointegration in dental implants. Materials and Methods: This experimental animal study was performed on four native male street dogs of 11–13 kg of weight and 16–20 months of age. The specimens underwent teeth extraction. After that, the dogs were randomly divided into two groups. The first group contains two control dogs which would receive oral saline. The second contains two dogs which would receive oral tablets of propranolol daily. After a period of healing, three titanium implants were inserted in each of speciments' left mandibular quadrant, and treatment was resumed with propranolol and saline administration in case and control group, respectively. After 4 weeks, one of control group dogs and one of case group were anesthetized, and dental implants were removed alongside the peripheral bone marrow using a trephine drill. Meanwhile, the other two dogs (1 control and 1 propranolol administered dogs) were anesthetized after 9 weeks of implant placement, and the same procedure was carried out. Results: Due to the histomorphometric assessment, the mean score of bone implant contact (BIC) in week 4 was significantly higher in case group compared to control one (68.33% vs. 20.22%). In week 9, the mean BIC score was higher in case group compared to control group (68.60% vs. 50.17%); meanwhile, in contrast to week 4, it was not statistically significant. In both case and control groups, the formation of woven and lamellar bone was more significant in week 4 rather than week 9. Conclusion: Administration of systemic β-blockers can improve dental implants osseointegration process.

This study aimed to identify and analyze the structure of “Knowledge and Information Science (KIS)” scientific articles using co-word analysis in the “Web of Science (WoS)” database. Methodology of this study was content analysis of articles. By co-word analysis of the articles, subjects and concepts of KIS were identified, using Between-Groups Linkage algorithm in clustering techniques. The study population was selected using the census sampling of 16475 journals’ articles in WoS database (2009-2013). Also, statistical analysis regression correlation was used. RaverPremap software, SPSS, and Excel were also used. Findings showed that the words "information", "web", "research", "citation analysis", "knowledge", "Library", "journals", and" technology" have high impact in studies. Analysis of clusters showed that articles words divide to 13 clusters. The main subjects of clusters includes “teaching and learning of KIS; Information literacy”, “Knowledge & Information Organization”, “Web resources and social networks”, “professional ethics in information science”, “informatics, communication and health information services”, “information management; information systems; knowledge management and innovation", “indicators of informetrics and scintometrics”. Analyzing of clusters’ concepts indicated emerging some other fields of science studies in KIS is phenomenon. Given the diversity and increases of scientific capital of other disciplines in KIS scientific outputs, interdisciplinarity of KIS knowledge was increased as well. Awareness of the interdisciplinary relation of KIS with other fields enabled experts to strengthen the cooperation with their researchers.

Abstract Background The presence of chemotherapy-resistant colorectal cancer stem cells (CCSCs) with KRAS mutation is thought to be one of the primary causes for treatment failure in colorectal cancer (CRC). P53, survivin, and microRNA-16-1 are challenging targets for anticancer drugs which are associated with chemoresistance in CRC. Yet, no p53-, survivin-, and microRNA-16-1-modulating drug with low toxicity but high efficacy against KRAS-mutant CCSCs have been approved for clinical application in CRC. Here, we investigated whether in vitro concentrations of DHA equal to human plasma levels, are able to modulate, Wt-p53, survivin, and microRNA-16-1 in CRC cells with stem cell-like properties. Methods Wt-p53/KRAS-mutant CRC cells (HCT-116) with stem cell-like properties were treated with 100-, 150- and 200-μM/L DHA, after which cell number, viability, growth inhibition, Wt-p53, survivin and microRNA-16-1 expression, caspase-3 activation and apoptotic-rate were evaluated by different cellular and molecular techniques. Results After 24-, 48-, and 72-h treatments with 100- to 200-μM/L DHA, growth inhibition- rates were measured to be 54.7% to 59.7%, 73.% to 75.8%, and 63.3% to 97.7%, respectively. Treatment for 48 h with indicated DHA concentrations decreased cell number and viability. In addition, we observed a decrease in both the transcript and protein levels of survivin followed by 1.3- to 1.7- and 1.1- to 4.7-fold increases in the Wt-p53 accumulation and caspase-3 activation levels respectively. Treatment with 100 and 150 μM/L DHA increased microRNA-16-1 expression levels by 1.3- to 1.7-fold and enhanced the microRNA-16-1/survivin mRNA, p53/survivin, and caspase-3/survivin protein ratios by 1.7- to 1.8-, 1.3- to 2.6-, and 1.3- to 2-fold increases respectively. A decrease in the number of live cells and an increase in the number of apoptotic cells were also observed with increasing DHA concentrations. Conclusion Wt-p53, survivin, and microRNA-16-1 appear to be promising molecular targets of DHA. Thus, DHA might represent an attractive anti-tumor agent directed against KRAS-mutant CCSCs.

The aim of the current research is the analysis of patent classes to recognize the subject areas of RFID technology. The research is a descriptive one and uses the clustering and the social network analysis techniques for data analysis. The research population consisted of 35, 627 patents that the term “RFID” or “Radio Frequency Identification” occurred in their abstracts or titles. Data analysis was performed through softwares like Excel, SPSS, NetDraw, and RavarMatrix. The findings showed that the growth of patents in the intended technology followed an exponential regression. The important subclasses were determined by two factors: number of years and frequency of use. It resulted in 803 important subclasses. The result of clustering for main classes also revealed that the RFID technology was associated with 31 subject areas. The axes or runts of these areas were Telecommunication and Electrical Communication. Social Network Analysis confirmed that the “Electrical Communication” have-had the most significant role for bridging other classes.

The current research aims at studying the epidemic model of the term RFID within the classes of patents. Methodology: The research is descriptive and has been conducted based on the mathematical models of diseases. Research population consists of 35,627 granted patents from the USPTO database those which the terms RFID or Radio Frequency Identification occur in their titles or abstracts. Data analysis was performed through software like Excel, SPSS, and Ravar-Matrix. Findings show that the cumulative growth of sub-classes with the term RFID follows an S-logistic model. This is an evidence of natural growth rate for assigning the term RFID to the USPTO sub-classes over the years. Other finding reveals that the term RFID has been entered into and exited from the sub-classes of patents like the SIS epidemic model of diseases. As a final conclusion, the most technical fields those that are susceptible for RFID technology, have been met this technology. On the base of SIS model, the epidemic of RFID technology has been reached a balance.

Introduction: Prediction of future subjects is a necessity for policy making in science field, which is done by different variables. Accordingly, present research was conducted to predict basic concepts in the field of colon cancer based on the factor of oldness and frequency use of subject terms. Methods: The present study was a descriptive-applied research. PubMed database was used to extract the data. Two separate searches were done on two 25-year-period studies, one from 1965 to 1989, and one from 1990 to 2015. In order to determine and predict important subjects of colon cancer domain (Colonic Neoplasms), two factors of oldness and annual frequency use of the terms were used. To do this, frequency and duration of the use of each of these terms were noticed in a period of 25 years. Then, climax or deterioration of the subject terms in future documents was predicted based on their reducing and increasing frequency in use during a special period. Results: Studying the degree of conformity between predicted subjects and newly found basic subjects in colon cancer etiology during 1990 to 2015, 128 subjects were predicted as the key subjects for future out of which, 73 cases (58%) occurred in the second period. In addition, studying the degree of conformity between the mentioned 73 cases and the second period basic subjects indicated that predicted subject issues constitute 22% of the key subjects of the second period. Conclusion: The results of the present research and the studies on predicting future trends showed that there was no method to predict the future subject issues with certainty and high accuracy. It seems that various methods of scientometrics and experts’ views should be considered together in order to have a precise prediction.

In this study, the influence of Furfurylation on practical properties of beech plywood investigated. Furfurylation of beech layers were performed by impregnation and heat catalyze up to 30% and 70% weight percent gain. Plywood specimens made by 2 resins (Urea Formaldehyde and Methylene Diphenyl Diisocyanate). Practical properties of furfurylated specimens investigated and compared to untreated specimens. Modulus of rupture (MOR), modulus of elasticity (MOE), shear strength, water absorption and thickness swelling were determined. Results revealed that by increasing the furfurylation level, modulus of elasticity (MOE), water absorption and thickness swelling (dimensional stability) improved. But modulus of rupture (MOR) just increased up to 30% furfurylation and decreased in higher levels of furfurylation. Furfurylation had a negative effect on shear strength of bond line and decreased by increasing the furfurylation level.

The current research aims at studying the conceptual relationship between the science and technology documents through the comparison of vocabularies that are used within the patents and the papers in the field of Autonomous Underwater Vehicles (AUV). The research method is descriptive. To perform the research, the patents were retrieved from Google Patents and Lens websites, and the papers from IEEE Explore database. A hybrid keyword-class method was used to conduct the search. It means that the search query was consisted of "Autonomous Underwater Vehicle" keyword and “H” class. The titles and the abstracts of the patents and the papers were automatically indexed through a semi-automatic method. This resulted in 195 keywords for patents and 114 ones for papers. Co-occurrence matrices of these two sets of keywords were created through RavarMatrix software. The hierarchical maps of keywords were drawn by SPSS. Findings show that 65 percent of papers’ keywords are those that occurred within the patents but 23 percent of patents’ keywords are similar to the papers’. The structural comparison of patents and papers clustering’s also revealed that the structural proximity between patents and papers vocabularies is equal to zero. The other finding showed that the similarity between the members of ego networks of prominent keywords is for two cases zero and for others fewer than 15 percent except for the keyword “data”. It may be concluded that the science is affected by technology in the field of AUV.

The purpose of the present study was to analyze the interdisciplinary relations of “Library Science and Information Science”. For this purpose the subject categories of citing and cited journals of these fields were investigated in JCR database during the period of 1987-1997 and 2003-2013, and through the comparsion of obtained results the impact of information technology on the development of “LIS” interdisciplinarity was investigated. Methedology of the research was co-citation analysis of journals in scientometrics studies. Also the research was performed using the conventional techniques of scientometrics including Bradford law, Ward hierarchical clustering approach in statistical software SPSS, and the new measure including Proximity index. Research community includes citing and cited journals of 56 “LIS” journals during 1987-1997 and 83 journals during 2003-2013 in Journals Ctiation Report (JCR) database. The results showed that “LIS” has been influenced by other subject categories more than affecting them. For example, the number of journals which “LIS” cited from 1758 (in the first period) has increased to 5303 (in the second period). Co-occurrence matrix of core citing and cited subject categories was analyzed, and three main clusters in the first period and seven clusters in the second period were drawn. In general, the amount and quality of co-occurrence of subject categories in clusters showed that the domain and variety of affecting and affected subject categories were expanded in the second period. Structural similarity of clusters for affecting and affected subject categories calculated. Results showed that structural similarity of clusters in the second period was %10 higher than in the first period. Also, the Structural similarity of affecting clusters of “LIS” was more than affected clusters. Assessment of difference between subject categories groups by ANOVA and Tukey Post hoc tests showed that there were differences between all numbers of citing and cited groups.

Introduction: Today, scientific collaboration has a rising trend in scientific journals. Therefore, the aim of ‎the current study was to analyze the co-authorship network among authors of the Journal of ‎Health Information Management (JHIM).‎ Methods: The present applied and descriptive study was conducted through social networks analysis ‎approach. In the present study, 568 articles published in the JHIM from 2006 to 2014 were ‎studied. The data were analyzed using UciNet software and SPSS software. Results: The findings revealed that a large amount of the articles were the results of the collaboration ‎of three main authors. In addition, 25% ‎of the authors were the most influential individuals in ‎producing journal papers. These authors mostly collaborated with authors of ‎lower rank. The ‎authors were divided into 3 categories of outstanding, active, and non-active.‎ Conclusion: It can be concluded that co-authorship has had a rising trend in the JHIM. As the results ‎revealed, the number of articles with ‎multiple authors has increased. It seems that the ‎increasing of outstanding authors should be one of the policies of this journal.‎

Background: The metabolic syndrome and periodontitis coincide with systemic inflammation and glucose tolerance disorder, which indicate the common pathophysiologic pathway of these diseases. The main goal of this study was to determine the effects of the metabolic syndrome on the periodontal indices of hemodialysis (HD) patient. Materials and Methods: In this descriptive-analytical study, 75 persons were selected by the simple method, 50 of them were HD patients, and 25 of them were healthy people. They were divided into three groups each of which included 25 persons. The periodontal conditions of the selected persons were determined by radiography, gingival index, probing pocket depth, and bleeding index. Then, the periodontal indices of the patients suffering from metabolic syndrome and the persons not affected by metabolic syndrome were compared. At the end, the data were analyzed by SPSS software (version 20) using Mann–Whitney and Kruskal–Wallis tests at the meaningful level of α = 0.05. Since the condition of the unilateral variance test could not be provided for this study, the Kruskal–Wallis test was used. To complete the test, the Mann–Whitney test was used in the binary form among the groups being studied. Results: The obtained results showed a meaningful difference among the groups under study (P < 0.001). The results of the test showed a meaningful difference among the obtained indices of the groups being studied in the binary form (P < 0.001) too. Conclusion: The results of the present study revealed when the severity of chronic systemic disease increased the health of the periodontal tissues would decrease.

The purpose of this paper is to present a fast, economical and practical method for mathematical modeling of aerodynamic characteristics of rectangular wing-in-ground effect (WIG). Reynolds averaged Navier-Stokes (RANS) equations were converted to Bernoulli equation by reasonable assumptions. Also Helmbold's equation was developed for calculation of the slope of wing lift coefficient in ground effect by defining equivalent aspect ratio (ARe). Comparison of present work results against the experimental results has shown good agreement. Finally, according to the calculated aerodynamic coefficients, height static stability of WIG was evaluated by Irodov’s criterion in various ground clearance (h/c). A practical mathematical modeling with lower computational time and higher accuracy was presented for calculating aerodynamic characteristics of rectangular WIG. The relative error between the present work results and the experimental results was less than 8%. Also, the accuracy of the proposed method was checked by comparing with the numerical methods. The comparison showed fairly good accuracy. The evaluation of Irodov’s criterion shows that height static stability (HS) increases with reduction of the height. Aerodynamic surfaces in ground effect were used for reducing wetted surface and increasing speed in high-speed marine and novel aeronautical vehicles. The proposed method is useful for investigation of aerodynamic performance and HS of WIG vehicles and racing boats with aerodynamic surfaces in ground effect. The proposed method has reduced the computational time significantly as compared to numerical simulation that allows conceptual design of WIG craft to do with economical.

Although a relatively new discipline, Knowledge Management (KM) is an area with a wide range of theoretical concepts and practical implications. The applicability of KM in different environments, and the vast value and benefits of its application, have led to great developments within the discipline over the last few years. The interdisciplinary nature of KM has also provided the opportunity for contributions by people from different disciplines, which in turn has lead to the rapid advancement of KM boundaries. This paper aims to examine the subject structure of the KM discipline through keyword analysis of documents in the Web of Science, using a hierarchical clustering approach and an inclusion index. Within the Web of Science categories, according to the findings, the three categories of "Management", "Computer Science Information Systems" and "Information Science Library Science" claim the highest number of documents in this area. Of 5570 author keywords, , 96 keywords are identified as "highly used" keywords. Three hierarchical clusters (dendrograms) are formed from co-occurrence analysis of highly used keywords in the three categories. A comparison of these denrograms indicates that six clusters, including a total of 16 keywords, are common in the three categories. Looking at clusters of the three categories revealed that two categories - Management and Information Science Library Science - have 14 common/shared clusters, and therefore the highest degree of similarities. However, the category of Computer Science Information Systems, with 28 unique clusters, differs most markedly from the other two categories. To investigate the rate of common keywords from one category to another, the inclusion index is calculated. Results of this exercise indicate that the category of Information Science Library Science has the highest number of common keywords.

Purpose: Each language has its own problems. This leads to consider appropriate models for automatic indexing of every language. These models should concern the exhaustificity and specificity of indexing. This paper aims at introduction and evaluation of a model which is suited for Persian automatic indexing. This model suggests to break the text into the particles of candidate terms and to cull the most appropriate ones through a special method of term weighting. Methodology: The introduction method of the automatic indexing model is performed through showing the steps and the possible problems for running them. Evaluation is based on the inclusion index. This index is used for determination the inter-indexer consistency. Therefore, the consistency of resulted index terms (from this model) and author keywords is determined. Findings: Findings show that 90% of articles' most weighted terms are similar to their first author keywords. The overall consistency between the results of running the model and author keywords is 76%. Compared with the prior works, the performance of the model is acceptable. Originality/Value: The initial value of this paper is concerning the automatic indexing with regard of Persian language problems. The model is well suited for using regular expression language which is supported by many programming languages. This diminishes the need to create database tables for text manipulation and processing. In addition, the model solves the problem of upper threshold for determination of final terms. Another algorithm makes it possible to determine the lower one. Finally, the number of culled terms does not depend on the text length. This guaranties the exhaustificity and specificity of indexing.

INTRODUCTION: Due to dynamic of terms, their classification is challenging. The current research aims at determining the usability of a model for automatic recognition of MeSH terms categories through measuring their occurrence frequency within relevant and non-relevant document corpuses from PubMed. METHODs: This is a descriptive research that uses the document analysis method. MeSH and PubMed were used to collect research data. The significancy of these resources confirms their validity. 18164 MeSH-term and 163226 PubMed documents were selected. The both of these amounts are greater than what Cocran function suggests. Eleven document corpuses were retrieved from PubMed. The relative ocurrence frequencies of MeSH terms within each corpus were determined. The results were compared with the real category of MeSH. In additions, the categories of 1 percent of MeSH terms were determined by experts in medical domains. The frequency distribution method was used for statistical description of data. Data were also analyzed through T and Chi-Squar tests in SPSS. RESULTS: Each document of PubMed on average belongs to three MeSH categoris and most of Mesh terms occurred in all corpuses. The results confirm that the suggested method increases the probability of MeSH category recognition. The performance of the method depends on the subject category of MeSH Term and ranges between 3 to 67 percent. The findings also show that the medical expertises determination on the subject category of MeSH Terms is compatible with the real categories of MeSH tree. CONCLUSION: The compatibility of the subjective and objective methods for the subject category recognition depends on the knowledge area. The subjective categorization is a quite cognitive task and roots in human environmental experiences. This is why the machine depended models are not able to simulate that process.

Citing national publications is considered as a qualitative measure for science localization in the current research. Consequently, the aim is to study this metric within the corpus of Iranian Scholar Journals in Social Science Domain between 2002 and 2010. Methodology: The research uses the citation analysis method. The references of six social science scholar journals were extracted from the papers and they were then divided into two groups of national and foreign publications. The studied journals were those which were regularly published in Iran between 2002 and 2010. The analysis performed on a sample of 543 papers out of 1528 ones. The sampling method was based on the Cochran’s function. Findings: An ANOVA test showed that the average number of citing to the national publications is statistically unchanged in the journal’s papers during the period mentioned above. On the other hand, the same average for foreign publications is growing. The correlation analysis determined that this growth follows a logarithmic function. The other finding concerns the differences between the average numbers of citing to the national publications in the studied journals. A one way ANOVA test revealed a difference between the journals from this point of view. Based on the Tukey’s Range Test the results of ANOVA test is affected by the "Journal of Women Strategic Studies". It means, if this journal were omitted from the analysis, the rest five ones would statistically have the same rate of citing to the national publications. The citing rate to national publications ranges between 0.31 and 0.39 except for the Journal mentioned above. Conclusion: Based on this metric, the tendency toward the use of national publications in the social science domain is constant despite the number of scientific productions is growing in Iran. This means that the Iranian social science domain not only doesn’t tend to the science localization but its use of foreign science is growing in the span of time as well.

Purpose: The aim of this research is to study the relationship between the co-authorship and the impact factor in Persian technical and engineering journals of Iran during the years 2001-2010. Method: The research method is analytic-descriptive with a citation analysis approach. The research population consists of 9321 papers from 77 Persian technical and engineering journals of Iran during the years 2001-2010. The data analysis was performed through Excel® and SPSS® v.20 programs. They were analyzed by statistics methods like, ANOVA, Chi Square, and Regression analysis. Findings: Findings showed that the average number of authors for Persian technical and engineering journals’ papers of Iran was not experienced a considerable change in the period mentioned above. The co-authorship was a dominant status in the papers that were studied but the average number of authors was slowly increases during the years of study. The findings also showed that a relationship is occurring between the co-authorship and Journal Impact Factor from 2010. Conclusions: The findings suggested that the co-authorship trend was unchanged during the studied period and the trend towards writing articles with two or three authors has been more significant. Occurring a significant relationship between the number of authors and the Impact Factor at the end of the studied period gives a positive outlook for the role of co-authorship in receiving more citations in future. As a final conclusion, the role of the number of authors in rising the chance for receiving more citations has been 17 percent among the other factors in Iranian technical and engineering journals.

Purpose: The current research focuses on selective dissemination of news and aims at finding patterns for recognition of readers’ favorite news through web mining technique. Method: Data for this research was collected from the Yahoo News Website. The source of news was Associated Press. 840 news dated between 2011/3/1 and 2011/5/10 was analyzed through subject clustering technique. Findings: Results show that 18% of news were visited over the average visit rate. Based on 80/20 rule, it is probable that 80% of readers interested in outstanding news. The other finding shows the gender as an influencing variable on individuals’ news interest. About 70% of readers were located in USA. This percentage should be more for non-English news websites. About 21% of readers were considered as active ones. This follows the 80/20 rule too. Based on another finding, the news in the same clusters receive the same number of comments from readers. This shows that the other news in the same cluster can be disseminated to the readers of a news. Finally, the use of cross sell pattern is appropriate for selective dissemination of news. Originality/Value: The reader’s comments under the news can be considered as an appropriate source for selection and dissemination of news. The current research offers patterns for selective dissemination of news through analysis of readers’ comments written under the news.

Background: Different methods have been suggested to preserve bone architecture following traumatic events such as teeth extraction. The purpose of the study was to histologically and histomorphometrically evaluate the dental socket healing after applying porous titanium granules (PTG) in dogs. Materials and Methods: Four healthy male dogs were involved in the present 6-weeks experimental animal study. Three sockets were surgically created in each side of dog′s mandible. One of the sockets in one side was randomly filled by PTG and covered by a resorbable membrane (Tigran + membrane group). Another socket was left unfilled and just covered by the same membrane (membrane group) and the last one was left unfilled and uncovered as the control group. The dogs were killed at two time intervals (2 weeks and 6 weeks, two dogs at each time point). All samples were histologically evaluated under an optical microscope for a new bone formation. Data were analyzed by SPSS ver. 16 and Kruskal-Wallis and Mann-Whitney tests were used to compare data in different groups (α = 0.05). Results: There was a significant difference between the Tigran + membrane and the control group in 2 and 6 weeks in the mean amount of total regenerated bone (P < 0.05). The mean amounts of woven, lamellar, and total regenerated bone showed significant differences between 2 weeks and 6 weeks for all three groups (P < 0.05). Conclusions: It can be assumed that the use of Tigran bone substitute with membrane can promote the bone regeneration in bone defects.

Background: The greater surface of bioactive glass nanoparticles presents an incomparable and promising feature similar to the biological apatite. Nanoparticles improve cellular adhesion, enhance osteoblast proliferation and differentiation, and increase biomineralization for periodontal regeneration and dental implants. Considering the fact that interaction between periodontal cells and bone graft materials are important for periodontal lesion regeneration, the present study was undertaken to investigate the genotoxicity of a novel synthesized nanoscale bioactive glass and compared it with Novabone bioglass in periodontal fibroblasts cells, in order to approve the biocompatibility of nano bioactive glass. Materials and Methods: In this in vitro experimental study, periodontal C165 fibroblasts cells were cultured in their logarithmic phase and the genotoxicity of novel synthesized bioactive glass nanoparticles and Novabone bioglass was studied in different concentrations and a control group using Comet assay test. By using Autocomet software, three parameters (Tail length, %DNA in tail, Tail moment) were analyzed; the genotoxicity of mentioned biomaterials and control group. Obtained data were analyzed by SPSS 11.5 software, Kruskal Wallis H and Mann Whitney tests (P = 0.05). Results: No statistically significant difference was observed between the concentrations of Novabone bioglass (P value = 0.085) with control group and novel nano bioactive glass (P value = 0.437) with control group in the evaluation of %DNA in tail parameter. There was significant difference between genotoxicity of novel nano bioactive glass and control, and between Novabone bioglass and control group in concentrations of 4 and 5 mg/ml. According to significance of the mean difference, novel nano bioactive glass showed higher genotoxicity compared to Novabone bioglass in the concentration of 5 mg/ml (P ≤ 0.05). Conclusion: The findings of this study have demonstrated that novel nano bioactive glass had no genotoxicity in concentrations lower than 4 mg/ml. Nanoparticles have a higher surface area in comparison to microparticles and thus, the amount and rate of ion release for nanoparticles are extremely higher. This difference is the main reason for the different genotoxicity of nano bioactive glass and micro Novabone bioglass in the concentrations higher than 4 mg/ml.

Introduction: It has been demonstrated that use of plasma rich in growth factors produces a dynamic surface on the implants, which accelerates the healing process. This study undertook a histologic and histomorphometric evaluation of the effect of platelet-rich growth factors (PRGF) on the amount of bone regeneration around dental implants.Materials and Methods: In this animal-intervention study, two systemically healthy Persian mix-breed dogs were selected. Three months after extraction of the dogs’ mandibular premolars on both sides, 12 implants were selected from the OIC system with a length of 10 mm and a diameter of 5 mm. Six implants were placed in the osteotomy cavities using growth factors and 6 others were placed in the osteotomy cavities without PRGF. After 12 weeks, all the implants were removed along with the surrounding bone using Trephine bur. The samples were evaluated under a light microscope subsequent to sectioning. Data were analyzed with t-test and Mann-Whitney test (α = 0.05).Results: The results of the present study indicated that histologically, there was a significant increase in the amount of regenerated bone around the implants; moreover, thickness and maturity of bony trabeculae were not different in the samples containing PRGF in comparison with the control samples.Conclusion: According to the results, implant-bone interface integration rate around dental implants coated with PRGF was higher compared to the control group Key words: Animal study, Dental implants, Growth factor, Histomorphometry, Histology, Plasma.

Introduction: Effective plaque removal is an important factor in the long-term clinical success of dental implants. The aim of this study was to compare the clinical efficacy of a powered toothbrush (Power Cross-Action) and a manual toothbrush (Cross-Action) in the control of plaque and soft tissue inflammation around implants supporting mandibular overdentures.Materials and Methods: This study was a cross-over clinical trial. The subjects included 10 edentulous subjects, aged 47-73 years, with removable mandibular overdentures supported by 2 unsplinted implants; all the subjects wore maxillary complete dentures. The study consisted of two 4-week phases separated by a 2-week interval. In each phase each subject randomly used one toothbrush type. Two days prior to each phase, the implants were polished. Plaque and bleeding indices were recorded before and after brushing. Data was analyzed by t-test using SPSS software (α = 0.05).Results: Both toothbrushes reduced the indices under study. Means of plaque index decreases were 0.5 in manual toothbrush and 0.44 in powered toothbrush. Means of bleeding index decreases were 0.27 in manual toothbrush and 0.3 in powered toothbrush. There were no statistically significant differences between the two toothbrush types in changing plaque index (p value = 0.88) and bleeding index (p value = 0.91).Conclusion: Both toothbrushes were efficient in plaque control around implants which supported mandibular overdentures and there was no difference between them. Patients can use one of these toothbrushes depending on personal preference and comfort. Key words: Dental implants, Hand toothbrush, Mechanical plaque removal, Overdenture, Powered toothbrush.