A Comparative Study of Soil Stabilization Effect and Concrete Strength Development on Rigid Pavement Thickness

تعتبر التربة الطبيعية هي الجزء السفلي الداعم للطريق الخرساني عند انتقال الأحمال المرورية المختلفة من سطح الطريق اليها فعندما تزيد قوة التربة فان قدرتها على استقبال الأحمال تزداد وبذلك تزيد من متانة الطريق الخرساني وديمومته وعدم التسبب بالمشاكل الإنشائية. اما إذا كانت التربة ضعيفة، فسوف يؤدي ذلك إلى نقصان في العمر الخدمي للطريق ويسبب أنواعًا متعددة من الفشل مثل تلف المفاصل وزيادة الاجهادات والانحراف والتصدع. بالإضافة إلى ذلك، فإن عملية تثبيت التربة تزيد من قوة التربة وتحملها للأحمال العالية، حيث أظهرت النتائج المختبرية أن استخدام 4٪ من المستحلب الأسفلتي أدى إلى تحسين خصائص التربة الجبسية وزيادة نسبة تحمل كاليفورنيا إلى 52٪. ان عملية تصميم الطريق الخرساني باستخدام طريقة تصميم AASHTO واعتمادًا على خصائص الخرسانة وخصائص التربة قبل التثبيت وبعده، وجد أنه أثناء الحسابات التصميمية عند تغير في قيمة CBR في حدود 27-52 ٪ وقوة انضغاط الخرسانة 30 ميجا باسكال نتجت في تقليل سمك الطريق بنسبة 7.5٪. لوحظ كذلك انخفاض بنسبة 7.8٪ في سمك الطرق عند تغيير قيمة CBR من نطاق 27-52٪ وقوة ضغط تبلغ 35 ميجا باسكال. لوحظ ايضاً انخفاض بنسبة 4.5٪ في سمك الطريق مع تباين في مقاومة الانضغاط من 30-35 ميجا باسكال وقيمة CBR تبلغ 27٪. بالإضافة الى انخفاض بنسبة 4.8٪ في السمك مع تباين في مقاومة الانضغاط من 30-35 ميجا باسكال وقيمة CBR تبلغ 52٪، لذلك نجد أن تأثير زيادة مقاومة التربة في تقليل سمك الطريق الخرساني أكبر من تأثير تغيير مقاومة الانضغاط للخرسانة.The subgrade soil is the supporting part of the concrete road for transferring the different traffic loads from the road surface. The strength of this soil increases its ability to receive loads, increases the durability of the concrete road, and does not cause structural failure problems. If the soil is weak, it will decrease pavement service life and cause multiple types of failure on the road such as damage to joints, an increase in stresses and deflection, and cracking. In addition, the soil stabilization process increases the soil's strength and its tolerance to high loads, so the laboratory results showed that the use of 4% of the asphalt emulsion led to improving the gypsum soil properties and increasing the California bearing ratio to 52%. In the process of designing rigid pavement using the AASHTO design method and depending on concrete properties and subgrade properties before and after stabilization, it was found that alterations in the CBR value within the range of 27-52% and a compressive strength of 30 MPa resulted in a reduction of 7.5% in slab thickness during the design calculations. A reduction of 7.8% in slab thickness was observed upon alteration of the CBR value from a range of 27-52% and a compressive strength of 35 MPa. A reduction of 4.5% in slab thickness was observed with a variation in compressive strength from 30-35 MPa and a CBR value of 27%. A reduction of 4.8% in slab thickness was found with a variation in compressive strength from 30-35 MPa and a CBR value of 52%. Therefore, it was found that the effect of increasing the soil strength on reducing the thickness of the concrete road is greater than the effect of changing the compressive strength of concrete

Using fuzzy logic approach to predict work-related musculoskeletal disorders among automotive assembly workers

Background: Musculoskeletal disorders (MSDs) are considered an important health concern, particularly in automotive assembly industries. Evaluation of the effects of all MSDs risk factors is difficult due to its multifactorial nature. In addition, the risk factors cannot be detected accurately when they are only based on individual opinions. Thus, in this study, fuzzy logic tool was used to evaluate the combined effects of all risk factors on MSDs. Methods: This cross sectional study was conducted on 100 male workers in an automotive industry. Job satisfaction, job stress, job fatigue, and body posture were evaluated by a self-reported questionnaire. Body posture was evaluated using Rapid Entire Body Assessment (REBA). Primary data analysis on extracting the input variables of MATLAB was performed by SPSS 22, with a significant level of 0.05. T test, one-way Anova, and Pearson correlation analysis were used to extract the input variables for the fuzzy logic model. The results obtained from the Nordic questionnaire was selected as the output of the fuzzy model. Fuzzy logic assessment was performed using MATLAB software version 7.0. Results: There were significant differences between WMSDs factors, including job fatigue, strain, working posture, and the REBA final score, and pain in all limbs of the body (p<0.05). A significant difference was also found between working posture with wrist score (p<0.05). The findings on defuzzification showed a strong correlation between real and modelling results. Conclusion: The results showed that many factors such as posture, fatigue, and strain affect MSDs. Based on the obtained results, all categories of risk factors, including personal, psychosocial, and occupational, should be considered to predict MSDs, which can be achieved by a modeling approach. Keywords: Automotive industry; Fuzzy logic; Work-related musculoskeletal disorders

Studying the Impact of Soil Stabilization Techniques on Rigid Pavement Joints Across Various Axle Loads

Rigid pavement slabs are erected on a prepared subgrade or foundation layer, providing a hard and continuous surface. Transverse joints made of dowel bars connect them, and longitudinal joints made of tie bars join them longitudinally. This study is an investigation of the impact of soil strength and concrete parameters on the effectiveness of dowel bars in rigid pavements. Moreover, three parameters were examined; California Bearing Ratio (CBR), concrete compressive strength and slab thickness. The analysis was conducted using the Ever FE program and focused on several axle configurations applied to the joint. The results indicate inverse association between the pavement slab thickness and the concrete strength, under the assumption of consistent soil strength. Moreover, an assortment of reduced shear forces on the dowel bars is seen when the soil strength values increase. It indicates that soil strength has a greater impact on the shear load of dowel bars compared to the qualities of concrete. Additionally, the type of axles used and the magnitude of soil strength were shown to have a significant effect on the shear load

Evaluation the influence of steel-fiber on the concrete characteristics

The impact of steel fibers on the engineering characteristics of concretes were explored experimentally in this work. Steel fibers of 0.5, 0.7, and 0.9 percent by volume fraction were applied to concretes mixture with water/cements (W/C) proportions of 0.43 to accomplish this. There have been a total of 24 cubic specimens produced for compressive strengths testing, 24 cylindrical specimens for splitting tension strengths testing, and 12 cubic specimens for toughened unit weight testing. The experimental findings reveal that applying 0.5 percent to 0.9 percent of fibers made of steel to concrete boosts both compressive and tension strengths concurrently when compared to ordinary concretes; however, there is no discernible gain in hardened unit weight with increased fiber amounts

Application of Dose Area Product (DAP) to Estimate Entrance Surface Dose (ESD) in Pediatric Chest X-Rays

Introduction: Given the high radiation tissue sensitivity of pediatric patients, it is necessary to monitor their received dose to optimize radiation protection. The first aim of this study was to evaluate the entrance surface dose (ESD) in pediatric patients undergoing a chest X-ray at the main hospital of Dezful, Iran. The second aim was to compare our results with the established dose reference levels (DRLs). Materials and Methods: The studied population included 204 pediatric patients less than 15 years who were referred to as chest X-ray. A calibrated dose area product meter (DAP-meter) with permanent installation on the X-ray unit was used to radiation dose measurements. For each patient, the demographic data, exposure parameters and the dose read by DAP-meter were recorded and ESD was calculated using a standard mathematical formula. Results: The average value of ESD was 119 μGy in patients less than 15 years. This value was 51.3, 122.3, 131.5 and 171.2 μGy for the age groups for less than 1 year, 1 to 5 years, 5 to 10 years and 10 to 15 years, respectively. A statistically significant difference was seen between ESD values ​​in different age groups (P&lt;0.001), whereas no statistical difference was seen between ESD values in ​ girls and boys (P =0.993). Conclusion: Pediatric patients in hospital investigated (except age group less than 1 year) are subjected to unnecessary radiation exposure, especially due to the use of non-optimize X-ray protocols

Cutaneous reactions to carbamazepine in children with epilepsy

BACKGROUND: The main components in controlling and treating seizures are antiepileptic drugs (AEDs). Mostly, the systemic side effects of these drugs are regarded very important; however, these drugs can also cause serious mucocutaneous side effects. Carbamazepine is a drug which is used to treat epilepsy. Side effects of this drug can range from skin rash to toxic epidermal necrolysis (TEN) and Stevens-Johnson syndrome (SJS). The purpose of this study was to evaluate skin complications of carbamazepine in children with epilepsy.METHODS: This study was performed on 99 children, aged 2 months to 11 years, with the diagnosis of skin complications after taking carbamazepine. Records were examined and their initial profiles including their medical skin conditions and rashes were recorded within the checklist. Data were entered into SPSS software. Measures of central tendency and dispersion were achieved. Finally, the relationship between the drug and the cutaneous reactions of these patients was analyzed using the chi-square test.RESULTS: The most common complications among the patients were maculopapular lesions and skin erythroderma, with the prevalence of 37.4% for each. Other types of skin lesions included papules with 14.1%, macules with 8.1%, and SJS with 3.0%. A significant association (P = 0.02) between the types of the skin lesion and the dose of carbamazepine was observed; the more the dosage was, the more severe skin lesions were.CONCLUSION: The most common cutaneous reactions to carbamazepine were erythroderma and maculopapular rash in the patients. The findings of this study also revealed that the lack of drug compliance was of high importance

Effect of Novel Zein Coating Combined with Different Antioxidants (Thymol and Carvacrol) on the Aflatoxin Production of Peanut

Introduction: Aflatoxin contamination of agricultural crops leads to health hazards and detrimental to the economy. Despite enhanced processing, handling and storage, it remains an issue in the peanut industry. An effort was made to investigate the efficacy of corn zein coating combined with thymol and carvacrol as the edible coating may extend aflatoxinproduction. Methods: Analysis of aflatoxins B1, B2 and total were performed for 11 treatments on coated and uncoated peanuts stored at room temperature for 90 days. Treatments were included zein, thymol (500, 1000, 1500 ppm), carvacrol (5000, 10000, 15000 ppm), incorporating thymol and carvacrol at three different concentrations and control. Results: Significant differences between coated and uncoated treatments were observed (

The therapeutic potential of losartan in lung metastasis of colorectal cancer

Colorectal cancer (CRC) is a common cancer with a high incidence rate. Components of the renin-angiotensin system (RAS) have been reported to be dysregulated in several malignancies including CRC. Here, we have explored the potential anti-metastatic effects of a RAS inhibitor, losartan, in an experimental model of lung metastasis in CRC. A murine model of lung metastasis of CRC was used, which involved the intravenous injection of CT26 cells via a tail vein. Four experimental groups comprised: an untreated group; a group that received 5-FU which was administered intraperitoneally; a losartan group that received a combination group that received 5-FU plus losartan . We evaluated the anti-inflammatory effects of losartan by histopathological method, and the measurement of oxidative or antioxidant markers including malondialdehyde (MDA) and total-thiols (T-SH) tissue levels, superoxide-dismutase (SOD) and catalase activity. We found that losartan inhibited lung metastasis of CRC and there was a reduction of the IL-6 expression level in the tissue sample. It was also associated with reduced levels of the anti-angiogenic factor Vascular endothelial growth factor (VEGF). Furthermore, we found that losartan induced oxidative stress as assessed by an elevation of MDA level, reduction of T-SH, SOD and catalase activities in lung tissue. Our findings demonstrated that losartan ameliorates angiogenesis, inflammation and the induction of oxidative stress via Angiotensin II type I receptor (AT1R). This may shine some lights on targeting the RAS pathway as a potential therapeutic approach in the treatment of metastatic CRC patients

Effect of Female Sex Hormones on Cardiorespiratory System: Theoretical Review

This study aimed at analyzing the effect of the female sex hormones upon  the cardiorespiratory system. And the results showed that the cardiac output measurement showed no significant increase during both phases of menstrual cycle before exercise but there was an insignificant increase soon after exercise owing to sympathetic over activity. The observed increase in the peripheral blood flow during mid-follicular phase before and after exercise revealed that influence of estrogen increases the arterial distensibility. The observed increase in the respiratory efficiency test during early luteal phase before and soon after exercise revealed the influence of progesterone, which is considered to be a potent stimulator of respiration, and added up effect of hormones and exercise-induced changes

Practices of Infection Control Among Dental Care Providers at Makkah

Background: A wide range of microorganisms poses a threat to patients and dental care teams. Implementation of safety guidelines is thus essential to prevent infection in dental clinics. Aim: To investigate the level of infection-control practices among dental health-care providers in Makkah. Methods: A self-administered questionnaire was distributed to dental care providers from hospitals, and dental centers. The questionnaire covered sociodemographic variables, professional characteristics, and recommended guidelines of infection control. Results: A total of 190 questionnaires were obtained out of 500 distributed questionnaires (response rate: 38%). Females accounted for 62.6% of the sample and 64.7% were dentists. The majority was vaccinated against hepatitis B (82.1%) and wash their hands as usual behavior before (66.3%) and after (83.2%) treatment. Approximately 87.9% wear gloves and 78.9% wear masks while performing dental procedures. Autoclave sterilization and puncture resistant containers for sharp instruments were used by 90.5% and 88.4%, respectively. The majority (81.0%) had protocols for emergency treatment of needle stick or other sharps accidents. High volume evacuation was used in 28.6% of public hospitals compared to 19.4% in academic institutions (P&lt;0.01). In addition, surface barriers for dental unit surfaces were used by 70.2% of private dental clinics, 50% of public hospitals, and 36.1% of academic institutions (P&lt;0.001). Finally, compared to dentists, dental support staff showed low compliance with infection-control guidelines. Conclusion: The overall practice of infection-control measures among the participants is very good. Educational programs and training strategies should be implemented to maximize and enhance the compliance of the dental care providers with infection-control guidelines. Keywords: infection control, dental care providers, vaccination, sterilization, disinfection