فهرست مطالب نجمه محمدی

Economic complexity is an index that has been raised in the last decade and indicates the use of technology in the process of producing goods and services of a country, which leads to increased economic growth and prosperity by creating a productive structure in the composition, increased productivity and diversity of manufactured products. Economic complexity is expected to affect energy consumption because the type of products produced is an important determinant of energy consumption. If countries operate in energy-intensive industries such as metals, chemicals, and forest products, energy consumption will be high, and if they specialize in low energy and highly complex products, energy consumption in these countries will decrease. In addition, the level of technological knowledge of countries can significantly affect energy efficiency. Therefore, in this research, the effects of economic complexity and economic growth on renewable, non-renewable and total energy consumption in developing and developed countries in the period of 2000-2020 have been investigated by GMM method.

GMM estimator is a subset of instrumental variable method estimators. In this method, in addition to solving the problem of correlation of the independent variable with disturbance components, the endogeneity of the variables and the heterogeneity of the variance of the model are also solved. It should be noted that this method is applicable when T is smaller than N (number of segments).

The results of this research show that the economic complexity index affects the development of renewable energy in developing and developed countries and also causes a decrease in the use of non-renewable energy and total energy consumption in developed countries and an increase in the use of non-renewable and total energy consumption in developing countries. It is currently being developed. In this research, the opening of trade has had a positive effect on the consumption of renewable energy in both groups of countries, and in developed countries, the opening of trade has reduced the consumption of non-renewable and total energy, and in developing countries, the opposite result has been obtained. In both groups of countries, energy consumption has a positive relationship with income level. Also, the results show that if economic growth is accompanied with higher technology, it can lead to a lower increase in total energy consumption in both groups of countries.

As mentioned in the introduction, economic complexity represents a complex and knowledge-based production structure of a given country that takes a long time to mature. When economic complexity increases, the use of non-renewable energy and environmental degradation increases first in a given country. However, with the increase of environmental preferences in a society, the economic actors change their energy by using non-renewable energy habits. This is completely consistent with the results of the estimation models as explained above. Based on the obtained results, it can be said that economic complexity is a policy factor for the overall transformation of renewable energy and demand for greener energy. The study recommends that complexity and structural change policies should be implemented for cleaner and greener growth and overall promotion of greener energy in developing and developed countries. Due to the movement of developing countries towards the development of technology, the need for energy will increase in the coming years. Hence, there is a need for policymakers to plan to meet energy needs. Considering the existing limitations in the use of fossil energy, which leads to complications such as environmental pollution and resource depletion, necessary investments should be made for the development of clean and renewable energy. In order to reduce energy consumption, policies that increase energy efficiency or prevent any form of  waste should be formulated, especially in economic sectors. In this regard, Can and Guzgur recommend that the level of fossil energy consumption in each industry should be clearly estimated and based on that, governments should establish specific laws for each industry. Through developing policies related to trade facilitation, they should also reduce the cost of importing new technologies, or decrease the cost of discovering new technologies via financing research and development institutions. Governments should promote energy regulations to reduce fossil fuel dependence and energy intensity. Future studies could examine the impact of economic complexity on energy demand in terms of oil-importing versus oil-exporting economies. Examining the effects of economic complexity on different aspects of energy (e.g., electric and nuclear energy) can be an important research question for researchers working on energy strategy.

Technology provides an opportunity for the economy to move from polluting sources to renewable sources to meet energy needs. Increasing economic complexity means more use of technology and innovation in production and may cause the expansion of effective technological products such as renewable energy. In the past few decades, the share of renewable energy has increased due to a wide range of factors, such as government regulations to promote the use of renewable energy, reduction in the cost of installing renewable energy and increasing production capacity, oil price fluctuations, and the positive effects of renewable energy in reducing emissions. Carbon and innovation processes have increased in the energy sector. Therefore, in this research, the effects of renewable energy consumption and economic complexity as well as their mutual effects on environmental pollution have been investigated using the GMM method in developing countries over the period 2000-2019.

In dynamic models, due to the presence of a lagged dependent variable, OLS or GLS methods cannot be used to estimate the model, because the disturbance components are correlated with the lagged dependent variable, and the estimation results are biased and inconsistent as before. Therefore, to solve this problem, the GMM method proposed by Arellano and Bond (1991) is used. The GMM estimator belongs to the set of instrumental variables’ estimators. In this method, in addition to solve the problem of the correlation of the independent variable with disturbance components, the endogeneity of the variables and the heteroscedasticity of the variances are also removed. It should be noted that this method is applicable when T (number of periods) is smaller than N (number of sections).

The results show that the economic complexity index has a negative and significant effect on carbon dioxide emissions in developing countries. Variables such as trade openness and energy intensity increase carbon dioxide emissions, and the Kuznets curve hypothesis is confirmed for developing countries, and economic complexity leads to an upward movement of the Kuznets curve. Renewable energy consumption has a significant effect on reducing carbon dioxide emissions, and also at higher levels of economic complexity, renewable energy consumption causes a greater reduction in carbon dioxide emissions.
Conclusion and

The need for a more accurate understanding of economic phenomena has prompted economists to review previous theories and present new theories that have a new window to economic development literature. The goal of all countries is to achieve sustainable economic growth and development. Renewable energy technologies are promising, but there is very little information about its role as a limiting factor in reducing environmental pollution, especially in developing countries. Therefore, in this research, the effects of renewable energy consumption and economic complexity as well as their mutual effects on environmental pollution have been investigated using the GMM method in developing countries over the period 2000-2019. The results show that the economic complexity index has a negative and significant effect on the emission of carbon dioxide, so it can be said that for developing countries, moving towards a more knowledge-oriented economy can improve the quality of the environment. The variables of trade openness, energy intensity significantly affect positively CO2 emissions. The EKC hypothesis was confirmed with the positive logarithm of GDP per capita and its negative square coefficient. According to the results of the study, economic complexity in countries under study leads to an upward movement of EKC, which means that as economic complexity increases in developing countries due to increased energy demand, scale effects occur and lead to higher CO2 emissions.
In this study, energy intensity has a positive effect on the increase in carbon dioxide emissions and as a result the increase in environmental pollution in developing countries.
The specific result of this article is the significant effect of renewable energy consumption on the reduction of carbon dioxide emissions in developing countries. At higher levels of economic complexity, renewable energy consumption causes a greater reduction in CO2 emissions. In terms of the role of complexity, it can be argued that in countries under consideration, the share of renewable energy should be significantly increased by using innovation processes in the energy sector. Considering the negative effects of the share of renewable energies on carbon dioxide emissions per capita, it is suggested to define new patterns of energy consumption by relying on renewable energies in development programs and using incentive tools to replace renewable energies instead of fossil fuels to reduce pollution. Developing countries should support knowledge-based industries, increase the import and production of environmentally friendly technologies, and increase the share of renewable energy in their plans to protect the environment. In addition, pricing strategies can be proposed to avoid increased fossil fuel consumption.

This work aimed to theoretically investigate the operation of the beta voltaic battery with the 14C radio isotopic source and several semiconductors in the p-n junction structure. For this purpose, the saturated thickness of the 14C beta source and energy deposition distribution of beta particles emitted from this source is simulated and calculated in the various semiconductors including the GaAs, GaN, SiC, and diamond using the Monte Carlo code of MCNPX. Regarding the results obtained, the optimized 14C thickness was achieved by 30 micrometers. Then, applying the analytical and numerical model, the relationships between the doping concentration, short circuit current density, open circuit voltage, and output power density were evaluated. The results showed that with   and    with the diamond as semiconductor, the output power density of designed battery was increased to 9.68 among the other considered semiconductors.

Acid mine drainage (AMD) as the most important environmental issue in mining sites is considered a significant source of environmental pollution.  AMD is typically produced by the oxidation of sulphide minerals, especially pyrite. The present study aims to investigate the acid production potential of the wastes of Mehmandoost coal washing plant located in NE Damghan. For this purpose, mineralogical, geochemical, and statistic tests were carried out on 7 representative coal washing waste samples. The obtained results show that although coal washing wastes are not enriched in Cu and Mn, they are moderately enriched in Ni and Co, significantly enriched in Cr, Sb and Zn, strongly enriched in Cd and As, and extremely enriched in Pb and Mo. The main mineral phases presented in the studied samples include quartz, muscovite, clinochlore, kaolinite, illite, montmorillonite, calcite and pyrite. In most of the studied samples, the pH and electrical conductivity (EC) of the saturated paste is <3 and > 2000 μm/cm, respectively. Moreover, in most samples the Net Neutralization Potential (NNP) is < -20. Also, in most of the samples, the Net Acid Production Potential (NAPP) is positive and the Neutralization Potential ratio (NPR) is < 3. The pH of Net Acid Formation (NAG pH) of these samples is < 4.5 and the ratio of Acid Neutralization Capacity to Maximum Acid Potential Acidity (ANC/MPA) is < 1. According to the results of static tests, there is a possibility of production of acidic drainage by the studied samples, therefore, taking suitable management measures to control acid production in the area is of crucial importance.

In accelerators operating energies above 7 MV, photoneutrons are produced by the interaction of photonuclear interaction with the heavy metals that constructed the linear accelerator (linac) head. Photoneutrons have destructive biological effects and increase the risk of secondary cancer in healthy organs outside the treatment area. In this study, the effect of flattening filter removal on the spectrum and dose of photoneutrons from the Siemens Primus 15 MV linear accelerator was investigated using the MCNPX2.6 Monte Carlo code. The results showed that removing the flattening filter increased the photon and photoneutron flux at the isocenter. The absorbed doses of photons and photoneutrons dose equivalent per incident electron on the linac target were also increased, without a flattening filter. However, in this case, the photoneutron dose equivalent per 1Gy of the photon absorbed dose at the isocenter is reduced to 50% at different distances from the isocenter.

Awareness of ethics principles is fundamental to morality in professionalism. Medical ethics courses are the most important source of knowledge about professional ethics. This study aimed to evaluate the effect of these courses on increasing the knowledge of dentistry students about professional ethics codes.

51 dentistry students at Shiraz University of Medical Sciences who had taken themedical ethics course in 2018 were evaluated through a multiple choice questionnaire related to the ethics code, with confirmed validity and reliability through an earlier published study (Cronbach′s alpa= 0.7). The students’ knowledge was evaluated before and after the course. Data were analyzed by SPSS software version 18 using the Wilcoxon test.

The mean score of the students' knowledge increased significantly after the course (74% versus 83%, P<0.001). The scores related to veracity, patient autonomy, and justice codes were significantly higher after the course. However, mean scores of the beneficence and non-maleficence codes did not show statistically significant differences (P values = 0.317 and 0.354, respectively). Veracity code, significantly improved after the course; however, the mean score was still low (39%)

The results of this study indicated that medical ethics courses effectively increased dental students' general knowledge about ethical codes. But in some certain aspects of ethical concepts like veracity, clinical and problem-based education are required.

Dosimetry of a pregnant woman under diagnostic imaging with ionizing radiation is very important due to the high radiosensitivity of the fetus and the destructive effects of radiation on it. In this study, the amount of S-values induced by the positron-emitting radiopharmaceutical 18F-FDG in different fetal organs were calculated using the MCNPX2.6 Monte Carlo code. In the simulations, hybrid phantoms of 3- 6- and 9-month pregnant women were used. The results showed that with increasing the fetal age, the self S-values of fetal organs decrease. A comparison between the calculated data in this study and those reported by other studies showed similar trend, however in some cases the data difference was up to 40% on average. These differences are due to the differences between the geometry of the used phantoms. Therefore, in order to more accurately estimate the dose to pregnant patient and her fetus, we intend to introduce a method for constructing a patient-dependent phantom using a limited number of measurements in our future studies, and thus increasing the accuracy of the calculated dose.

Low birth weight is one of the most widespread public health problems associated with high infant mortality. This study aimed to identify maternal risk factors affecting low birth weight neonates in Rafsanjan hospitals.

This case-control study consisted of 120 low birth weight infants (less than 2500 grams) as the case group and 120 normal weight infants (2500 grams and more) as controls in 2018. The data were collected by a randomized checklist from the records of the delivery mothers in the hospitals of Rafsanjan and were analyzed using Chi-square, independent t-test and logistic regression.

According to the results of the tests, the number of prenatal care and gestational age at birth was lower in the case group than in the control group, but the history of low birth weight was higher in the case group. Logistic regression for the history of low birth weight (OR=4.196, p=0.008) in the case group was more than the control and mean birth interval (OR=0.992, p=0.036) and gestational age at birth delivery (p<0.001, OR=0.61) was lower in the case group than in the control group.

Findings showed that low number of prenatal care, having low birth weight, preterm delivery, and low birth interval have a role in low birth weight. Therefore, increasing pregnancy care coverage and paying attention to mothers who have low birth weight and preterm birth and increasing the interval between births can decrease low birth weight infants.

Dental pulp health is very important during permanent dental root completion that takes place in the first three years after eruption. Any injury to the dental pulp during endodontic treatment or physical trauma causes disruption in the improvement of root formation. In this case it had been searched for a conservative treatment of permanent immature teeth

The patient was a 9 years old boy with severe carries of immature teeth number 36. The pulp was exposed and does not respond to any heat or electric test that shows pulp necrosis. Apexification treatment was done with applying intracanal medicament.

If an appropriate treatment is selected for immature necrotic teeth, root formation can be followed.

Premature loss of primary teeth affects child's nutrition, sleep, growth, and self-confidence. Besides, it can cause undesirable movement of the primary or permanent teeth.

This paper reports a 5.5-year old boy presenting with severe-early childhood caries, who had suffered from early extraction of some primary teeth as well as several other dental problems. After thorough clinical and radiographic evaluations, the treatment plan consisted of two phases. In the first phase, the focus of the treatment was on oral hygiene instruction, fluoride therapy, restorative procedures, pulp treatments, and extraction of non-restorable teeth. In the second phase, space management strategies were considered.

We designed a new modification of Groper's appliance to serve as space regainer and space maintainer, simultaneously. By replacing the extracted primary anterior teeth, both the parents and the patient were satisfied with the results.

Many developments in the last two centuries have made women to tend increasingly towards social acvies and employment. This had led to change or mulplicity of their family and social roles, resulng in new challenges. One of the main aims of the present paper is to review female faculty members’ condions in facing their family and professional roles. A qualitave method and phenomenological approach is used in this paper. The data are gathered through problem-oriented interview and its parcipants are 13 female faculty members of universies in Tehran who were selected through systemac sampling. The research findings are classified into four main themes of “family role and playing role in family”, “professional role and playing role in university”, simultaneity of playing family and professional roles”, and “facing with how to solve the problems of simultaneity of playing double roles”. Conceptual understanding of categories resulted in the fact that female faculty members face with some challenges in terms of mulplicity of their family and professional role and a balance can be easily made between their roles and responsibilies if proper strategies and plans are adopted by individuals, families and relevant organizaons, based on the recommendaons of a religious model.

The Orthognathic Quality of Life Questionnaire (OQLQ) was designed by Cunningham in 2001 to assess the quality of life of patients in relation to orthodontic treatments. This study sought to evaluate the validity and reliability of the Farsi version of OQLQ in 10-14 year-olds in Shiraz. This descriptive analytical study was conducted on 240 students in the age range of 10-14 years that were randomly selected from the 4 educational districts in shiraz. One elementary and one middle school were selected from each district. The OQLQ questionnaire contains two sections. The first section asks for demographic information of patients and the second part contains 22 questions regarding the quality of life in relation to dental status. This questionnaire was translated to Farsi using the standard forward-backward translation method. The standardized Cronbach’s alpha، alpha if item deleted، item-total correlation and inter-item coefficients were used for the assessment of the reliability and validity of the questionnaire. For the calculation of test-retest validity، 30 students filled out the questionnaire again 2 weeks after the first session. Mann Whitney U and Chi square tests were used to assess the correlation between the different aspects of the quality of life in the questionnaire and willingness to take the treatment. Data were analyzed using SPSS version 18 software. The internal consistency analysis of the OQLQ indicated a good correlation between questions and domains of the questionnaire. Cronbach’s alpha in this study was 0. 86. For the calculation oftest-retest reliability of the questionnaire، weighted kappa was found to be 0. 91. Mann Whitney U and Chi square tests found significant differences between willingness for orthodontic treatment and dentofacial esthetics (part 2، P=0. 008) and knowledge about dentofacial esthetics (part 4، P=0. 018). Farsi translation of OQLQ is a suitable tool for the assessment of the effect of dentofacial problems on thequality of life of orthognathic patients in an Iranian population.

The orthognathic quality of life (OQOL) questionnaire evaluates the quality of life in five aspects which are related to the dentofacial status of an individual. In this study the association between the orthodontic treatment willingness and these aspects was evaluated in 10‒14 year-old students in Shiraz. In this cross-sectional analytic study، 240 participants among 10‒14 year-old students in Shiraz were selected. The OQOL questionnaire was used for the evaluation of five aspects of the orthognatic quality of life. After completion of the questionnaire، the students were asked to answer a question about their willingness for orthodontic treatment with Yes or No and according to this answer، the participants were categorized in two groups. The case group involved those who answered with Yes (n=113) and the control group involved those who answered with No (n=127). Data was analyzed with the SPSS 15 using Mann-Whitney U test (α=0. 05). The scores of three components، including “self-confidence” (p value = 0. 009)، “awareness of dentofacial esthetic” (p value = 0. 018)، and the “dentofacial esthetic” (p value = 0. 023) were statistically significant. The difference between the case and the control groups were not significant in the “social aspect” (p value = 0. 070) and the “oral function” (p value = 0. 154). Based on the results of this study، in the adolescent age group، “self- confidence”، “dentofacial esthetic” and “awareness of dentofacial esthetic” are the most effective aspects of orthognathic quality of life (OQOL)، which result in willingness for orthodontic treatment.

At present different techniques are used for the removal of carious lesions. Chemomechanical caries removal technique is a noninvasive technique that removes the infected tissue، and at the same time، maintains sound tooth structures and prevents pulpal irritation and patient discomfort. The aim of this study was to evaluate shear bond strength of a two-step self-etch adhesive to demineralized dentin after caries removal in primary molars with Carisolv in comparison with a handpiece.

In this in vitro study، 60 freshly extracted primary molars with occlusal caries were collected. The samples were divided into two groups. In each group، the teeth were cut in mesiodistal and buccolingual directions to prepare four samples. In group 1، the carious lesions were removed using Carisolv gel and in group 2، they were removed using a bur in a handpiece. Then the teeth were restored with composite resin and Clearfill SE Bond adhesive، using molds measuring 2 mm in height and 1. 4 mm in diameter. The bonding interface underwent a shear strength test in a universal testing machine. Numerical values ​​of shear bond strength (SBS) were calculated for each group، and statistical analysis was performed with t-test using SPSS software program (α = 0. 05).

The mean SBS values of Carisolv and handpiece groups were 19. 7 ± 6. 1 and 17. 3 ± 5. 5 MPa، respectively، with no statistically significant differences between the two techniques (p value = 0. 308).

Based on the results of the present study، the bond strength of Clearfil SE Bond adhesive to dentin after caries removal using the two techniques (Carisolv and handpiece) did not exhibit significant differences.

Recurrent aphthous stomatitis (RAS) is an oral lesion with high prevalence. Its management is directed toward treatment of symptoms. Myrtle is an herbal drug that has been used for RAS treatment during last years. Its essential oil has antiseptic and antimicrobial properties. One of the best factors in the treatment of aphthous lesion is, remaining of drug in location, so, a dosage form was tried to design that can hold the drug for a long time in location. For this purpose mucoadhesive drug delivery system was selected. Methods & Materials: This study was a double blind randomized clinical trial. The essential oil was extracted from myrtle leaf by using water in Clevenger apparatus. Oral mucoadhesive paste was prepared by compounding of sodium carboxy methyl cellulose, pectin and gelatin in plastibase. The best formulations were selected for clinical trial. In this double blind clinical trial, individuals were divided into two groups, A and B that received Mocuadhesive paste containing myrtle essence and mucoadhesive paste without drug as placebo, respectively. The size of lesions was measured by periodontal probe at 1, 2, 6 and 10 days. Also by use of VAS scale, daily pain was measured at 10 days period.

The time of burning sensation relief in A and B groups were 1.64±0.74 and 4.91±1.30 days respectively, which there was significant difference between the two groups (P<0.001). The mean of lesion size in group A were 0.14±0.36 and in group B 2.73±1.68 (mm) in sixth day (P<0.001).

The Mocuadhesive paste containing myrtle essential oil is a suitable formulation for treatment of recurrent aphthous stomatitis, with regard to its adhesive properties, the reduced time of burning sensation and the reduced size of lesion, significantly.