r. ahmadi

The main purpose of the present research, is not to cut the floor of stone block in quarrying dimensional stones in order to save the costs of the quarry operation and reduce the operation time. By using methods such as drilling parallel drill holes, containing quarry with feathers and wedge, use of expansion chemical materials and overlapping parallel drill holes methods, initial cutting the stone as well as separating it from the mountain without need to cut the floor is possible. Of course, in these methods, there are always limitations on the height and thickness (width) of the block and the speed of operation is low. Therefore, to achieve the goal, experimental studies were carried out, especially in the quarry method with diamond cutting wire in Mahallat, Hajiabad travertine mine located in Markazi province as a case study. In some zones of this mine, especially zone 14, there is a layer of shale under the travertine layer. In the experiment process, to simulate the reality in practice, first, two perpendicular vertical cuts (with a ninety degrees angle to each other) were created on the samples in the laboratory. Then, using a wedge-shaped steel piece with a flat end, a vertical force was applied into the crack of the stone samples. The results of the present research through experimental studies on four travertine stone samples of Mahallat Hajiabad with natural and fine layering, showed that by applying vertical force into the cracks of the samples without any floor cutting, smooth and flat fracture surfaces were created in the mechanically weak surfaces of the stone. This finding reveals the possibility of quarrying travertine building stone mines with layering and high height, by diamond wire cutting quarry method without the need for floor cutting.

To improve children’s writing skills through philosophy one could look at a novel such as Suki Novel and its Instructional Manual for use in philosophy for children program to see what the requirements of writing ability are indicated to be in the novel, and how these requirements can be strengthened. To this end, the content analysis of the novel and its manual revealed the purpose of writing is creation and regeneration of thought through words. As such, it is the mission of any educational system to help with improvement of writing ability in children by emphasizing skills such as defining, exemplifying, categorizing, and clarification of concepts, mental exercise, storytelling, discovering ambiguities, and reasoning. Such skills not only strengthen the writing ability constituents, but help students with writing both beautifully and logically.

In this study, adsorption of procarbazine on the surface of fullerene (C20) was studied computationally. For this purpose, the structures of fullerene (C20), procarbazine and the derived products from the interaction of procarbazine with fullerene at three different configurations were optimized geometrically. Then, IR and frontier molecular orbital calculations were implemented on them in the temperature range of 278-314 K at 3˚ intervals. The obtained thermodynamic parameters including Gibbs free energy changes (ΔGf), and formation enthalpy alterations (ΔHf) have revealed that the adsorption of procarbazine is exothermic, spontaneous, one-sided and experimentally feasible at the both evaluated configurations. The influence of temperature on the thermodynamic factors of the desired process was also inspected and the results indicate that 298.15 K is the best temperature for the fullerene (C20) substitution on procarbazine. Some HOMO-LUMO related parameters such as energy gap, electrophilicity, chemical hardness, maximum transferred charge index (ΔNmax) and chemical potential were also calculated and discussed in details.

In this study, adsorption of melphalan on the surface of single walled carbon nanotube was studied computationally. For this purpose, the structures of carbon nanotube, melphalan and the derived products from the interaction of melphalan with carbon nanotube at two different configurations were optimized geometrically. Then, IR and frontier molecular orbital calculations were implemented on them in the temperature range of 298-398 K at 10˚ intervals. The obtained thermodynamic parameters including Gibbs free energy changes (ΔGf) and formation enthalpy alterations (ΔHf) have revealed that the adsorption of melphalan is exothermic, spontaneous, one-sided and experimentally feasible at the both evaluated configurations. The influence of temperature on the thermodynamic factors of the desired process was also inspected and the results indicate that 298.15 K is the best temperature for the carbon nanotube substitution on melphalan. The calculated specific heat capacity values have shown that the sensitivity of the produced carbon nanotube- melphalan derivatives to the heat and shock have declined significantly. Some HOMO-LUMO related parameters such as energy gap, electrophilicity, chemical hardness, maximum transferred charge index (ΔNmax) and chemical potential were also calculated and discussed in details.

To investigate the effect of the selection of different race-specific normal databases on the densitometric results and diagnosis. Eighty-two participants included in the study were selected consecutively from the archived scans. Analysis was conducted three times for each participant using different ethnicities (White, Asian and Hispanic) as the race-specific normal database for comparison with the patient’s data. The densitometric data, including bone mineral density (BMD), as well as T- and Z-scores, were extracted for three standard regions, including the spine, femoral neck, and total femur. The agreement among the diagnoses based on three different ethnicities (White Vs. Asian, White Vs. Hispanic, and Asian Vs. Hispanic) was tested by cross-tabulation and calculation of the coefficient of Kappa. The mean and standard deviation of the T-score of participants with the selected reference types were exactly the same in all three regions. The mean and standard deviation of the Z-score of all participants, in comparison with "Asian" and "white" references, was exactly the same, but with the cases where the "Latin" race was selected as the reference, in the region of the neck, thigh (p<0.001) and the whole thigh (p<0.001) was different. Z-score values of the spine were the same in all three racial groups. The Z-scores of the spine were the same in all three types of races. Bland-Altman analysis demonstrated a significant difference in the femoral neck but not in the spine and total femur. All the diagnoses based on WHO and ISCD criteria were the same (Agreement test: Kappa coefficient=1.00 and P-value<0.001). The study shows that the effect of the selection of different race-specific normal databases is insignificant on the densitometric results and diagnosis.

In this research, the performance of Carbone nanotubes (CNT) as a sensing material and adsorbent for the detection and removal of Amoxicillin was investigated. at the first, the structures of Amoxicillin and CNT were optimized with Gaussian program. Then, using the molecular docking strategy and its grading system, they were computed the arrangement of 10 structures with more negative binding energy than other . Finally, for the best arrangement of Amoxicillin with CNT, molecular orbitals evaluations and depedents parameters , binding energy and other thermodynamic parameters evaluated, the results indicated that the adsorption of Amoxicillin antibiotic on CNT was an exothermic. This procedure was carried out at 298 K and 1 atm. Finally, the QTAIM calculations were performed to evaluate the type of interaction and bonds created between amoxicillin and CNT.

Wheat straw is one of the wastes produced in agricultural section that is burned in the farmlands entering huge greenhouse gases into the atmosphere. The aim of this study is to evaluate thermal energy loss from external walls of a building constructed using fired clay hollow bricks filled with compacted wheat straw. Hence, fired clay hollow bricks compared to those filled with compacted wheat straw (having a density of 0.156 g cm-3) were used to build up the walls of an experimental container model outdoor and thermal energy loss throughout the walls of it were evaluated. Comparison of thermal properties of the constructed walls using non insulated fired clay hollow bricks or insulated with compacted wheat straw including: thermal conductivity, heat flow rate and heat transfer coefficient showed decreasing from 0.2 to 0.04 W m-1 ºC-1, 18.36 to 6.98 W m-2 and 1.7 to 0.41 W m-2 °C-1, respectively, for insulated walls. The results revealed a decreased thermal energy loss between 72 to 81 percent from walls of the building constructed once compacted wheat straw with the compaction degree applied.

Otosclerosis is caused by abnormal bone remodeling in the middle ear, which is associated with dizziness and lightheadedness. An underlying cause of dizziness in this disease can be the presence of an enlarged vestibular aqueduct. In this study, the prevalence of enlarged vestibular aqueduct in these patients compared to the normal population has been investigated.

In this cross-sectional study, 26 people with bilateral otosclerosis and 26 people with at least one healthy ear requiring a CT scan were compared. Vestibular aqueduct was tested by evaluating the two factors of the midpoint width between the external diaphragm and the common crus, and its width in the external diaphragm region and comparing the two groups. Bone conduction, speech detection threshold, and gap between bone conduction and air conduction were calculated and compared in otosclerosis patients with enlarged versus normal vestibular duct.

The median width of the vestibular aqueduct in the area of the external aperture in patients with otosclerosis (1.2 mm) was significantly greater than that of healthy subjects (1 mm) (p=0.046). Regarding the size of the vestibular aqueduct in otosclerosis patients, 5 patients (9.6%) were found with enlarged vestibular aqueduct in radiological findings. However, this difference was not statistically significant. In otosclerosis patients, bone conduction threshold in all frequencies was significantly higher in people with enlarged vestibular aqueduct compared to other patients (p<0.001).

Based on the results of this study, the prevalence of enlarged vestibular aqueduct in patients with otosclerosis is considerable, and it is better to pay enough attention to the CT scan of patients before surgery to prevent possible complications.

On March 29, 2021, UNESCO held a virtual meeting of education ministers under the slogan "One year into covid, priority given to improving education to prevent generational catastrophe".The purpose of this meeting was to review the lessons learned from this new situation, the most important risks head and strategies to prevent academic backwardness. One of the main themes of the meeting was the digital transformation and the future of education. Following the pandemic of covid-19 disease in Iran and other countries of the world and the horizon opened in the application of e-learning, it is necessary to develop indicators to evaluate the quality of this training. The purpose of this research is to evaluate the quality of learning management system based on ISO 9126 standard.

In this research, descriptive-survey research method was used. Data collection tool was a researcher-made quality questionnaire of e-learning management system that was designed based on ISO 9126 indicators. To check the validity of the measurement tool, Question analysis, reliability and validity were used. To analyze the questions, the methods of calculating the difficulty index   , discriminative index and loop method and for  face validity, content validity and construct validity were used to validate the questionnaire. Its validity was confirmed by experts and its reliability was obtained using Cronbach's alpha of 0.907.  To analyze the data, two methods of descriptive and inferential statistics were used by SPSS software. In the descriptive statistics section, tables of frequency, mean, graphs and standard deviation, frequency percentage and in the inferential statistics section, one-group t were used to test for significant differences. The statistical population of this study included Master's and PhD students of Shahid Rajaei teacher training University Virtual Education Center, which was calculated by random sampling method to 161 people based on Klein's view.

According to statistical tests results the results indicate that the quality of the learning management system, virtual learning centers operating in the components and reliability is low-middle level, and components of usability is medium to high levels and components of efficiency is medium levels. The results of t-test indicate that the mean obtained in 160 degrees is significant with 95% confidence. Therefore, the quality of e-learning management system of the statistical population based on ISO 9126, with 95% confidence is in the middle to lower level.

In the learning management system, the ISO 9126 standard to determine the quality of software is one of the most important topics in e-learning which has been considered as an influential factor in various researches. In terms of the necessary of changes the world's educational systems and the tendency to use virtual education, Managers of educational systems are advised to ensure the provision of high quality training by identifying the weaknesses of the e-learning software system and paving the way for their elimination. Also, in accordance with the standards, provide the necessary infrastructure for the purposeful use of these systems. In investigating the cause of low quality of learning management system based on ISO 9126 standard, there can be weaknesses in the sub-characteristics of these components such as adaptability, compliance, security, fault tolerance, recoverability, time behavior, resource behavior, installability, analyzability and stability named.

In the present research, to fully recognize the Yazd, Darreh-Zereshk copper deposit, 3-D multiple-log of the boreholes lithology, cross-sections of lithology and assay data corresponding to profiles covering the whole area and 3-D lithology model of the deposit were plotted using Rockworks software. Based on this, limestone, skarns, sandstone, diorite, granodiorite, quartzite and monzonite perform the dominant lithology of the region and the surface of the area is mostly covered by overburden, shale and lime. Depending on the deposit conditions, to estimate the deposit reserve, inverse distance squared method as a geometric method and geostatistical kriging method were used through Surpac software. According to the deposit variography using WinGslib software, the deposit has geometric anisotropy and maximum range of 130 m with azimuth zero, mean range of 100 m with azimuth 90 and minimum range of 40 m on the vertical direction with azimuth zero. After geometric modeling and producing block model of the deposit, the reserve was estimated for cut-off grades of 0.1, 0.2, 0.3, 0.4 and 0.5% copper as well as their results were compared. The results of the reserve calculation show that the difference of the calculated reserves with applied methods is relatively high, i.e. for cut-off grade of 0.1% is about 1547600 tones or 5.7%. Although, inverse distance squared method is the most accurate method among the geometric methods of reserve estimation, geostatistical kriging method considering spatial structure of the region, being unbiased and having minimum estimation variance is more accurate with higher degree of validity.

The aim of this study was the effect of topotecan on the activity of nitric oxide synthase in the tumor cell line Hela in comparison with the normal Hek cell line.

For this purpose, Hela and Hek cells were randomly divided into the control groups and treatment groups exposed to 7.8, 15.6,31.25, 62.5,125, and 250 µg/ml of topotecan for 24,48,72 hr. Then, the data analysis of plate supernatant was evaluated the number of live cells using the MTT method, grease reaction as well as Real-Time PCR method and the data were compared using the one-way ANOVA statistical method between groups.

The viability of Hela cells exposed to 250, 125, and 61.5 µg/ml of topotecan significantly decreased in comparison to the control group in 24, 48, and 72 h (p≤0.05). Also, the level of nitric oxide in Hela cells that were exposed to 250 µg/ml drug increased ½ times in comparison to the control group.

Topotecan has an inhibitory effect on cervical cancer cells. Also, topotecan increased the level of nitric oxide in Hela cells and this amount of nitric oxide kills the cells in cervical cancer cells.

Despite many studies carried out on the application of stem cells in the healing of diabetic wounds, the results are still challenging. The aim of the present study was to determine the effects of gelatin hydrogel containing adipose-derived mesenchymal stem cells on diabetic wound healing in animal model.

In the present experimental-laboratory study conducted in 2019, mesenchymal stem cells were isolated from human adipose tissue and at that point characterized. The gelatin hydrogel was made using the microbial transglutaminase enzyme. Diabetes was induced in Wistar male rats by injecting streptozotocin. Subsequently, 0.8 cm thick wounds appeared on the backs of the mice. Animals were divided into control groups (treated with normal saline) and treated group with hydrogels containing adipose tissue-derived mesenchymal stem cells. Wound healing was assessed on days 7, 14 and 21 days after treatment through wound imaging. Data were analyzed using t-test and one-way analysis of variance.

The wound area decreased significantly in rats treated with “hydrogel + mesenchymal stem cells” on post-treatment days 7, 14 and 21 compared to first day of treatment (P<0.01, 0.001 and P<0.001, respectively). Unlike control group, the wound area significantly decreased on day 14 compared with day 7 in treated group.

Conclusion

Mesenchymal stem cells transported by gelatin hydrogel to the wound site, cause faster healing of diabetic wounds, therefore, can be used as a dressing for diabetic wounds.

Photogrametry with UAV (unmanned aerial vehicle) is a fast, accurate and cost-effective approach to obtain high-resolution spatial information. Taking overlapped photos of the target, production of 3-D dense point cloud, digital elevation model and orthomosaic from the region surface as well as verifying their accuracy using a definite number of ground control points, are main stages of the process. In the present research, photogrametry through UAV was used for monitoring, modeling and evaluation of exploited and residual ore reserve of Qods sand and gravel mine in Lanjan district of Isfahan. Based on dimensions and form of the region, nine flight lines with approximately 37m interspacing and 114m flight altitude were designed and traversed. The total number of photos taken from the region is 225 with 75% and 65% longitudinal and transverse coverage for the images, respectively. The number of six control points (five control points and one check point) were also scattered at the region so that the error range from -1.5 to 1.5mm with the total error of about 6.8mm is the appropriate precision. Total accuracy of the survey operation using the UAV was validated through comparing with ground check point via accurate three frequency GPS. The survey errors in the three coordinate directions are negligible, less than 5cm. At the end, the volume of exploited part and residual deposit was determined and with multiplying by average density (1.4 gr/cm3), the amount of extracted and residual ore reserve was calculated 3657.43 and 82942.55 tones, respectively.

In the present research, the situation of chromite in Iran has been investigated in terms of production, import and export during 10 years period (1387-1396 in Persian calendar and 2008-2017) as well as the position of Iran has been determined in the world. Over these years, Iran ranked 10th in the world by producing between 1 to 1.5 percent of the world’s chromite production. Investigating the import and export of chromite ore and concentrates in Iran through 1388 to 1396 also reveals that while the export varies between 20 and 160 million dollars, the top of imports can’t even reach to 850000 dollars. Neighboring countries such as Oman, Turkey and Turkmenistan, Asian countries containing China, India and Japan and European countries like Spain make up the most important export target markets of Iran’s chromite, which China with 99.7 percent is the largest importer of Iran’s chromite. Iran ranked 6th in global exports of chromite but the presence of Iran’s rival economies in Asia and the Middle East such as Turkey, Kazakhstan and Pakistan in the ranking above Iran, predicates serious rivals in the region. During 2008 to 2017 Iran’s relative quota of the chromite global exports is between 1 and 6 percent. The results of the research show that the state of the country is promising in all three sectors of the production, import and export of chromite ore and concentrates. It means that by increasing production and appropriate planning on target markets, exports will also be increased in the future.

In this study, the effect of recycled water on the grade and recovery of lead and zinc sulfide flotation in comparison with Tap water has been investigated. The ore sample was prepared from Anguran lead and zinc mine, and the process water sample was prepared from KZG (Kimia Zanjan Gostaran) lead and zinc flotation plant. The results showed that when process water is used compared to Tap water, the recovery and grade of Galena and Sphalerite decreased. In Galena flotation, the recovery using Tap water was 3% higher than process water, and the grade with Tap water was significantly higher (8%). In Sphalerite flotation with Tap water, the recovery and grade were significantly increased (11% of recovery and 10% of grade). Investigation of the oxides in Galena and Sphalerite concentrates revealed that the number of oxides that were non-selective activated in the presence of process water is higher. This result is due to flotation reactant residues in these waters and their Precipitation on Galena and Sphalerite ores and non-selective activation of other minerals.

To investigate the effects of sowing date and nitrogen fertilizer on the quantitative and qualitative characteristics and nitrogen efficiency in Lallemantiaiberica (M.Bieb.) Fisch. & C.A.Mey. and Lallemantiaroyleana (Benth.) Benth., an experiment was conducted as a factorial split plot in a randomized complete block design at the Faculty of Agriculture, Shahed University. The treatments included the sowing date as the main plot at two levels of autumn and spring sowing, and the nitrogen fertilizer at three levels of 0, 50 (8 kg ha-1), and 100%(16 kg ha-1) and two Lallemantia species as the subplots. The results of analysis of variance showed the significance of the effects of sowing date, nitrogen fertilizer, plant species, and the interaction of all three treatments on grain yield, 1000-grain weight, harvest index, leaf area index, leaf chlorophyll content, seed protein, nitrogen, and mucilage content, and nitrogen uptake, use, and utilization efficiencies. The autumn sowing in comparison with the spring one had the most positive and incremental effect on the studied traits except seed nitrogen. The results showed that the application of 16 kg ha-1 nitrogen fertilizer on both sowing dates increased the quantitative and qualitative characteristics of both Lallemantia species compared to the non-fertilizer application conditions. Increasing the use of nitrogen fertilizer compared to the non-fertilizer application conditions increased the nitrogen uptake and use efficiencies in the autumn and spring sowing dates in both Lallemantia species. Increasing the use of nitrogen fertilizer in the autumn sowing increased the nitrogen use efficiency in both Lallemantia species, but in the spring sowing, the nitrogen use efficiency was higher under the non-fertilizer application conditions compared to the different levels of nitrogen fertilizer application. L.iberica showed a more positive reaction to the nitrogen fertilizer application compared to L.royleana.

In addition to its natural and initial functions, walking stick or cane, as an important cultural and mythical symbol, has a great presence in myths and religions. Once upon a time, it was used as a simple tool in routine tasks; but gradually it acquired new functions in the life of people. In subsequent periods and in close relation with the intellectual development of man, it emerged in symbolic form. Symbolic functions of cane have been changed in different mythical and religious periods. Sometimes due to these changes, its connection with its roots is cut away and appears in a different form. On the other hand, along with technological advances, the functions of cane are assigned to more advanced instruments such as spear, bow, sword and modern weapons. In the present article the attempt is made to explain the role of cane and its various functions in myths and epics in conjunction with the gods, kings and heroes. Also, its presence in different religions and its symbolic roles as well as gradual change of these roles are considered.

Studies have shown that ibuprofen can have an anti-cancer effect on cervical cells, although the mechanism of this effect is not well known in cellular and molecular terms. Accordingly, the aim of this study was to investigate the effect of cytotoxic concentration of ibuprofen on the activity of caspases -3, -8 and -9 in cervical cancer (Hela) cells.

In this experimental-laboratory study, Hela cells were prepared from Pasteur Institute cell Bank and were divided into the control group and groups exposed to 0.01, 0.1, 1 and 10 mg/ml of Ibuprofen. Viability of cells was measured by MTT assay. The activity level of caspases-3, -8 and -9 was assessed by colorimetric method. The data were statistically analyzed using ANOVA.

The viability decreased significantly in cervical cancer cells exposed to 0.1 (76%), 1(64%) and 10(15%) mg/ml of ibuprofen compared to control group (100%)(p<0.05, p<0.001 and p<0.001 respectively). The caspases-3، -8 and -9 activity level increased significantly in cervical cancer cells exposed to IC50 dose of ibuprofen compared with control group (p<0.001, p<0.001 and p<0.01 respectively).

The results of present study showed that ibuprofen is able to reduce the viability of cervical cancer cells in a dose-dependent pathway, and this pathway is induced by activating of caspases-3, -8 and -9.
 
 

The purpose of this study was to develop a structural model of students' academic engagement based on the achievement and self-regulation goals with the mediating role of academic motivation. In a descriptive-correlational study, 473 female students from the second-cycle secondary schools in the city of Ilām were selected, using a random stratified sampling method. They responded to a self-report questionnaire including the Zerang academic engagement questionnaire, Elliot and McGregor  (2001) achievement goals Inventory, Valerand, Peltier, Blys et al (1992) Educational Motivation Scale and Self-Regulatory Questionnaire (MSLQ). The results of the structural equation analysis showed that mastery-approach and performance-approach achievement goals have a significant indirect effect on academic engagement by mediating internal and external motivation. The self-regulation variable also had a significant indirect effect on the academic engagement by mediating internal and external motivation. Also, self-regulation had a direct positive and significant effect on the academic motivation; the achievement goals of mastery-approach and performance-approach had a direct effect on internal and external motivation, and the internal and external motivation had a direct effect on the academic engagement. According to the results of this study, identification of variables associated with the academic engagement can help educators to organize the educational programs and environments that leads to the selection of the desired achievement goals, the development of the students' self-regulation skills and motivation and, consequently, increasing their academic engagement and improving the educational outcomes.

Given the impact that new technologies have had on individual and social activities, it is the task of education to respond to the growing needs of the society. To emphasize this task, UNESCO, in 2008, in collaboration with major companies such as Microsoft, Intel, Cisco, the International Association of Education Technology, the Polytechnic Institute and the University of Virginia, designed a document for teacher information and communication technology knowledge. Due to the importance of the issue and the welcome of member countries, this document was further revised. In the introduction to this document, students and teachers must be able to use technology effectively to live, learn and function successfully in highly complex, knowledge-based and information-rich environments. Education should strive to design students with specific characteristics that meet the needs of today's societies by designing an appropriate environment. Some of these characteristics are: capable of using information technology, searcher, analyst and information evaluator, decision maker and problem solver, capable of effective and creative use of productivity tools, informed, responsible and participatory citizens. By increasing the daily and effective use of technology in the educational process, student-teachers gain the opportunity to learn through technology. The growth and development of various information and communication technologies has made it possible to build a variety of software, hardware and Internet networks that can help the educational system of any country in a variety of formal, informal and free learning. Accordingly, given the important role that the teacher has in organizing learning experiences, it is necessary for them to be trained in a way that finds the necessary attitude, knowledge and skills. Accordingly, in-service and pre-service professional programs for teachers should include objective experiences of information and communication technology in the professional dimension. The present paper aims to construct, validate and estimate the reliability of the questionnaire of technology competencies of student-teachers at Shahid Rajaee Teacher Training University (SRTTU) in Tehran.

To do so a questionnaire was developed after a systematic review of literature on theories of technology competencies. Through a random cluster sampling a sample of 60 student teachers of SRTTU was selected and the questionnaire was administered among them. The instrument included 49 items. Item analysis such as item discrimination and loop, construct validation (factor analysis) and reliability analysis (Cronbach Alpha) were utilized.

In factor analysis, three factors were identified as: technology knowledge, knowledge consolidation and knowledge production. The reliability of the questionnaire turned out to be .98. The results indicate that the instrument is both reliable and valid and can be readily used to assess student-teachers’ technology competencies.

The results indicate that the instrument is both reliable and valid and can be readily used to assess student-teachers’ technology competencies.

This study, master's dissertation of instructional technology were analyzed in point of methodological and executive context. Research methodology was content analysis and all master's dissertations of the public universities of Iran were selected. The total study population was selected as a sample (279dissertations were selected from Alameh Tabtabaei, Kharazmi and Arak University). Results indicate that master's dissertations of instructional technology has been conducted with positivist paradigm and relayed on quantitative approach, and the most methods that were used include experimental, survey, correlation and content analysis. Executive context analysis indicated that the most of researches have been carried out at the universities and schools, and other contexts such as industries and business have rarely been considered.

An association have been reported between diesel exhaust and endocrine disorders in several studies. Hence, this study aimed to investigate the effects of diesel exhaust on serum levels of T3, T4 and testosterone in male rats.

In this laboratory experimental study, 24 male Wistar rats were randomly divided to 4 groups (6 series) consisting of the control group and groups exposed to 1, 4 and 8 hours daily diesel exhaust. After 10 weeks, blood samples were collected using cardiac puncture method and the levels of T3, T4 and testosterone were measured by radioimmunoassay following the serum collection. The study data were statically analyzed using ANOVA.

T3, T4 and testosterone serum levels did not significantly change in rats exposed to diesel exhaust for 1h/day compared to control rats, whereas these serum levels significantly increased in group exposed for 8h/day compared to control animals (P<0.05, P<0.01 and P<0.001, respectively).

The study findings indicated that prolonged exposure to diesel exhaust results in increased thyroid and testicular activity, according to which exposure to diesel exhaust, particularly prolonged exposure can be accounted as an important factor associated with thyroid and sex glands disorders.

Studies reveal that there is an association between smoking and serum levels of sexal steroid hormones. The main aim of this study was to determine the effects of cigarette or waterpipe smoking on serum level of LH, FSH, and testosterone in male rats.

Male Wistar rats were randomly divided into control, cigarette, and waterpipe smoking groups, each consisting of 10 participants. After 6 weeks, blood samples were collected using cardiac puncture method. Following serum collection, levels of LH, FSH or testosterone were measured by radioimmunoassay method. Data were statistically analyzed and compared between groups using ANOVA.

The results indicated that serum FSH level was significantly increased in cigarette smoke and waterpipe smoke receiving rats compared with control ones (P<0.001). Serum levels of testosterone were decreased in cigarette or waterpipe smoke groups in comparison with control animals (P<0.001). Furthermore, Serum level of LH was not significantly changed in waterpipe and cigarette smoke receiving rats.

Our finding indicated that there was no significant difference between effects of cigarette and waterpipe smoke on serum testosterone, FSH and LH levls.