Islamic University of Gaza
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حدوث الطفيليات المعوية وخصائص النظافة بين مقدمي الأغذية في قطاع غزة-فلسطين
No full textBackground: The present study aimed at investigating the presence of intestinal parasites among food handlers in Gaza Strip.
Methods: A cross-sectional study was carried out where a total of 214 stool samples were collected from food handlers. The study was performed in the period between October 2007 to April 2009. The stool samples were tested by wet mount using normal saline, Lugol’s iodine and sedimentation techniques using formalin and ether. A questionnaire was filled for each food handler including, age, residence, hygiene characters, work place and education level.
Results: The study revealed an overall prevalence of parasites in food handlers of 24.3%. The most common protozoan parasite was Entameba histolytica/dispar ( 19.2% . It was found that the age group 26-36 years had the highest prevalence of Giardia lamblia. It was found that city workers had the highest prevalence of intestinal parasites while camp workers had the lowest prevalence.
Conclusions: It is concluded that a high percentage of food handlers are infected with intestinal parasites. It is recommended that food handlers should be subjected to regular medical examination that includes stool analysis.هدف الدراسة الحالية للبحث في وجود الطفيليات المعوية بين مقدمي الأغذية في قطاع غزة- فلسطين. تم عمل دراسة مقطعية حيث تم جمع 214عينة براز من مقدمي الأغذية و أجريت الدراسة في الفترة الواقعة بين أكتوبر 2007 الى ابريل 2009. تم اختبار عينات البراز بطرائق مختلفة: الفحص المباشر للعينة باستعمال المحلول الملحي، و الصبغ بالايودين، و الترسيب بالايثر الفورمال، تم ملئ الاستبانة من كل مقدم أغذية و التي تشمل على معلومات مثل :العمر، مكان الاقامة ، خصائص النظافة، مكان العمل و مستوى التعليم. كشفت الدراسة ان نسبة الشيةع العامة للطفيليات بين مقدمي الأغذية وصلت الى 24.3% وكان الأكثر شيوعا طفيل المتحولة الحالة للنسيج / دسبار 19.2% . وجد أن الفئة العمرية 26-36 سنة كان لها أعلى معدل شيوع للجارديا اللمبلية. بينت الدراسة أن معدل شيوع الطفيليات كان أعلى بين مقدمي الأغذية المقيمين في المدينة بينما المقيمين في المخيم أقل شيوعا. خلصت الدراسة أن هناك نسبة عالية من مقدمي الأغذية مصابة بالطفيليات المعوية وبالتالي يوصى الباحثون أن يخضع مقدمي الأغذية لفحص طبي منتظم و الذي يتضمن تحليل عينة براز
Epidemiology of acute diarrheal diseases among Children under five in Gaza Strip: Post war community based study
No full textDiarrhoeal disease is the second leading cause of death in children under five years old, and is responsible for
killing around 760 000 children every year. To study the determinants and the magnitude of acute diarrheal diseases one
month after the cessation of the third Israeli aggression against Gaza Strip and to assess its burden among the children
under five. This is cross sectional design study. Data has been collected throughout Gaza Strip. The sample size included
705 women from three governorates were surveyed out of five. Eligible women were interviewed using a pre designed,
pre tested interview questionnaire. The period (last month) and the point (24 hours) prevalence rates of diarrheal diseases
among children under five years were 46.1% and 17.7% respectively. The Sex of the child had no significant effect on
both point and period prevalence of diarrhea. More than sixty percent (63.3%) of period prevalence of diarrhea was
recorded among children that have no exclusive breastfeeding before. There are no significant differences for the point
prevalence as a result of introducing the complementary feeding. Period and point prevalence rates of diarrhea were not
significantly related to the room number. Both rates were higher for children in homes without refrigerators but only
significant for point prevalence. It was found that 62.1% of the mother increased fluid intake, 54% of them used ORS.
Drugs like anti diarrhea and herbal drugs were used by (61.4% and 40.3%) respectively of the participating mothers.
Cleaning of drinking water tanks and the domestic tanks have played a role in reducing the occurrence of diarrhea among
children under five with highly statistically significant between both of them. It is concluded that there was high point
and period prevalence of diarrhoea still exists among children in Gaza Strip. It is recommended to start to search for
diarrhoea causes to reduce its incidence
Chemical attack on concrete containing a high volume of crumb rubber as a partial replacement for fine aggregate in engineered cementitious composite (ECC)
No full textToday, scrap tire is disposed of by open burning which harms the environment. To reduce the wastage of the resource, a sustainable approach is needed to dispose of the waste tire as a partial replacement of the fine aggregate in concrete mixes. This research has been conducted with a focus on the chemical attack of an engineered cementitious composite (ECC) containing a high volume of crumb rubber in terms of durability, behaviour, and comparison with conventional concrete. Two variables have been considered in developing rubberized ECC mixtures, that is, the amount of crumb rubber as a replacement for fine aggregate by volume of 0%–30% and PVA fibres by volume of 0%–2% to cementitious materials. The resistance properties of ECC incorporating crumb rubber were investigated for 13 different variable combinations developed using response surface methodology (RSM). The experimental results revealed that the presence of crumb rubber in the ECC matrix enhanced the resistance of the ECC in both acidic and sulphate environments. It was also revealed that by incorporating 15% crumb rubber, the loss of compressive strength significantly reduced from 38% to 15%.Today, scrap tire is disposed of by open burning which harms the environment. To reduce the wastage of the resource, a sustainable approach is needed to dispose of the waste tire as a partial replacement of the fine aggregate in concrete mixes. This research has been conducted with a focus on the chemical attack of an engineered cementitious composite (ECC) containing a high volume of crumb rubber in terms of durability, behaviour, and comparison with conventional concrete. Two variables have been considered in developing rubberized ECC mixtures, that is, the amount of crumb rubber as a replacement for fine aggregate by volume of 0%–30% and PVA fibres by volume of 0%–2% to cementitious materials. The resistance properties of ECC incorporating crumb rubber were investigated for 13 different variable combinations developed using response surface methodology (RSM). The experimental results revealed that the presence of crumb rubber in the ECC matrix enhanced the resistance of the ECC in both acidic and sulphate environments. It was also revealed that by incorporating 15% crumb rubber, the loss of compressive strength significantly reduced from 38% to 15%
تصميم وتركيب وتقييم بيولوجي لمشتقات بايرزولو الجديدة [1،2،4] مشتقات تريازولوبيريميدين كعقاقير محتملة مضادة للسرطان
No full textThree novel pyrazolo-[4,3-e][1,2,4]triazolopyrimidine derivatives (1, 2, and 3) were designed, synthesized, and evaluated for their in vitro biological activity. All three compounds exhibited different levels of cytotoxicity against cervical and breast cancer cell lines. However, compound 1 showed the best antiproliferative activity against all tested tumor cell lines, including HCC1937 and HeLa cells, which express high levels of wild-type epidermal growth factor receptor (EGFR). Western blot analyses demonstrated that compound 1 inhibited the activation of EGFR, protein kinase B (Akt), and extracellular signal-regulated kinase (Erk)1/2 in breast and cervical cancer cells at concentrations of 7 and 11 µM, respectively. The results from docking experiments with EGFR suggested the binding of compound 1 at the ATP binding site of EGFR. Furthermore, the crystal structure of compound 3 (7-(4-bromophenyl)-9-(pyridin-4-yl)-7H-pyrazolo[4,3-e][1,2,4]triazolo[1,5-c]pyrimidine) was determined by single crystal X-ray analysis. Our work represents a promising starting point for the development of a new series of compounds targeting EGFRقطر الخيريةThree novel pyrazolo-[4,3-e][1,2,4]triazolopyrimidine derivatives (1, 2, and 3) were designed, synthesized, and evaluated for their in vitro biological activity. All three compounds exhibited different levels of cytotoxicity against cervical and breast cancer cell lines. However, compound 1 showed the best antiproliferative activity against all tested tumor cell lines, including HCC1937 and HeLa cells, which express high levels of wild-type epidermal growth factor receptor (EGFR). Western blot analyses demonstrated that compound 1 inhibited the activation of EGFR, protein kinase B (Akt), and extracellular signal-regulated kinase (Erk)1/2 in breast and cervical cancer cells at concentrations of 7 and 11 µM, respectively. The results from docking experiments with EGFR suggested the binding of compound 1 at the ATP binding site of EGFR. Furthermore, the crystal structure of compound 3 (7-(4-bromophenyl)-9-(pyridin-4-yl)-7H-pyrazolo[4,3-e][1,2,4]triazolo[1,5-c]pyrimidine) was determined by single crystal X-ray analysis. Our work represents a promising starting point for the development of a new series of compounds targeting EGF
Role of expanded clay aggregate, metakaolin and silica fume on the of modified lightweight concrete properties
No full textThis investigation aimed to assess the effect of micro-cementitious materials on the mechanical properties and sulphate resistance of modified eco-efficient lightweight concrete (MDLWC). A modified lightweight concrete (MDLWC) was produced by mixing Light-expanded clay aggregate (LECA) with normal coarse aggregate (dolomite cushed rock). The impact of using different percentage of micro-cementitious materials which was micro silica fume (5–20%) and metakaolin(10–35%) on the mechanical properties (compressive strength, splitting tensile and flexural strength), waves transmission velocity of the ultrasonic pulses and sulphate resistivity of MDLWC was studied. The overall results illustrated that the use of micro-cementitious materials in MDLWC caused an enhancement on MDLWC properties. However, the MDLWC specimens containing micro silica fume showed better results than metakaolin. The best results were observed while using samples containing 10% micro silica fume and 30 % metakaolin individually or combined. In addition, the usage of combined mixture of 10% micro silica fume and 30% metakaolin MDLWC mix showed the best improvement rate in compressive, splitting tensile and flexural strengths by 25, 53.3 and 66.6%, respectively, compared to control MDLWC specimens. On the other hand, the direct empirical equations were proposed on the basis of strong and nonlinear regression analysis using the test data to predict the mechanical properties of MDLWC relationships, rationally. Experimental tests were conducted on ultrasonic pulses velocity, which showed good correlation equation strength of MDLWC. Scanning electron microscopy illustrated that the pores of concrete is smaller for SF and MK individually or combined with MDLWC compared to the control concrete, demonstrating an enhancement within the interfacial microstructure with the pozzolanas incorporation. The previous difference could be explained due to the concrete strength and sulphate penetrability to an extent.This investigation aimed to assess the effect of micro-cementitious materials on the mechanical properties and sulphate resistance of modified eco-efficient lightweight concrete (MDLWC). A modified lightweight concrete (MDLWC) was produced by mixing Light-expanded clay aggregate (LECA) with normal coarse aggregate (dolomite cushed rock). The impact of using different percentage of micro-cementitious materials which was micro silica fume (5–20%) and metakaolin(10–35%) on the mechanical properties (compressive strength, splitting tensile and flexural strength), waves transmission velocity of the ultrasonic pulses and sulphate resistivity of MDLWC was studied. The overall results illustrated that the use of micro-cementitious materials in MDLWC caused an enhancement on MDLWC properties. However, the MDLWC specimens containing micro silica fume showed better results than metakaolin. The best results were observed while using samples containing 10% micro silica fume and 30 % metakaolin individually or combined. In addition, the usage of combined mixture of 10% micro silica fume and 30% metakaolin MDLWC mix showed the best improvement rate in compressive, splitting tensile and flexural strengths by 25, 53.3 and 66.6%, respectively, compared to control MDLWC specimens. On the other hand, the direct empirical equations were proposed on the basis of strong and nonlinear regression analysis using the test data to predict the mechanical properties of MDLWC relationships, rationally. Experimental tests were conducted on ultrasonic pulses velocity, which showed good correlation equation strength of MDLWC. Scanning electron microscopy illustrated that the pores of concrete is smaller for SF and MK individually or combined with MDLWC compared to the control concrete, demonstrating an enhancement within the interfacial microstructure with the pozzolanas incorporation. The previous difference could be explained due to the concrete strength and sulphate penetrability to an extent
Technological performance of açaí natural fibre reinforced cement-based mortars
No full textAçaí (Euterpe oleracea Mart.) is a fruit from forests typical of South American countries, such as Brazil. The fruit is harvested from palm trees and later processed to produce several food and aesthetic products that bear considerable health benefits. The processing of açaí generates substantial amounts of waste, such as natural fibres, which are generally disposed of in landfills. The objective of this work is to evaluate the technological performance of adding açaí fibre (with additions of 1.5%, 3.0% and 5.0% relative to cement mass) in its natural condition and after surface treatment with NaOH in mortars based on cement and lime. Açaí fibre was physically, chemically and microscopically characterised. The properties of consistency, water retention, incorporated air content, mechanical strength (compression and flexion), mass density (fresh and hardened state), capillary water absorption and durability (wetting and drying cycles) were analysed as well. Results show that açaí fibres in additions of up to 3.0% relative to cement mass and properly treated with NaOH solution can be used as reinforcement mechanism for mortar applications.Açaí (Euterpe oleracea Mart.) is a fruit from forests typical of South American countries, such as Brazil. The fruit is harvested from palm trees and later processed to produce several food and aesthetic products that bear considerable health benefits. The processing of açaí generates substantial amounts of waste, such as natural fibres, which are generally disposed of in landfills. The objective of this work is to evaluate the technological performance of adding açaí fibre (with additions of 1.5%, 3.0% and 5.0% relative to cement mass) in its natural condition and after surface treatment with NaOH in mortars based on cement and lime. Açaí fibre was physically, chemically and microscopically characterised. The properties of consistency, water retention, incorporated air content, mechanical strength (compression and flexion), mass density (fresh and hardened state), capillary water absorption and durability (wetting and drying cycles) were analysed as well. Results show that açaí fibres in additions of up to 3.0% relative to cement mass and properly treated with NaOH solution can be used as reinforcement mechanism for mortar applications
Effect of high temperature on the mechanical properties of basalt fibre self-compacting concrete as an overlay material
No full textBasalt fibres are modern inorganic concrete fibres, fabricated by melting the basalt rock. These fibres exhibited remarkable resistance to elevated temperatures in comparison with other manufactured fibres. Thus, when the impact of fire is the main consideration, basalt fibres are favoured in the construction of concrete buildings. In this study, the effects of basalt fibres on the workability of fresh self-compacting concrete (SCC) were measured using slump flow, J-ring flow, V-funnel flow and L-box height ratio. The properties of hardened concrete such as compressive strength, splitting strength, modulus of elasticity, flexural strength, and Poisson’s ratio were examined at temperatures between 25 °C and 500 °C. Also, the bond strength between the basalt fibre SCC as an overlay material and a normal concrete substrate was analysed at elevated temperatures. The interfacial surface between the concrete parts of the hybrid samples was roughened in different ways to determine the best roughening mode, which induced high slant shear strength of concrete under fire. The experimental results revealed that increasing the temperature up to 500 °C reduced the tensile and compressive strengths of SCC by over 20%. The optimum slant shear strength of hybrid concrete under fire was achieved by roughening the interfacial surface through the sandblasting method.Basalt fibres are modern inorganic concrete fibres, fabricated by melting the basalt rock. These fibres exhibited remarkable resistance to elevated temperatures in comparison with other manufactured fibres. Thus, when the impact of fire is the main consideration, basalt fibres are favoured in the construction of concrete buildings. In this study, the effects of basalt fibres on the workability of fresh self-compacting concrete (SCC) were measured using slump flow, J-ring flow, V-funnel flow and L-box height ratio. The properties of hardened concrete such as compressive strength, splitting strength, modulus of elasticity, flexural strength, and Poisson’s ratio were examined at temperatures between 25 °C and 500 °C. Also, the bond strength between the basalt fibre SCC as an overlay material and a normal concrete substrate was analysed at elevated temperatures. The interfacial surface between the concrete parts of the hybrid samples was roughened in different ways to determine the best roughening mode, which induced high slant shear strength of concrete under fire. The experimental results revealed that increasing the temperature up to 500 °C reduced the tensile and compressive strengths of SCC by over 20%. The optimum slant shear strength of hybrid concrete under fire was achieved by roughening the interfacial surface through the sandblasting method
Highly sensitive nano-sensor based on a binary photonic crystal for the detection of mycobacterium tuberculosis bacteria
No full textTuberculosis is a widespread disease all over the world. Early diagnosis plays a crucial role in the treatment of patients and can reduce the mortality rate. A new biosensor based on a binary photonic crystal is designed for the detection of mycobacterium tuberculosis bacteria in the blood. The structure air/(A/B)N/(Defect)/(A/B)N/air is employed, where A, B and N are the first and second layers and the number of periods, respectively. Layers A and B are chosen as GaAs and BaF2, respectively. The defect layer is the blood sample. The transfer matrix method (TMM) is utilized to simulate the structure. Some parameters, such as central wavelength, defect layer thickness and incident angle are optimized to maximize the sensitivity. The optimum sensitivity is found 3197.18 nm/RIU, which is extremely high when compared to the most recent papers published in this field. In addition, our sensor has a simple design, tunable fabrication and low cost and can be useful for the detection of many
organisms that can exist in the blood.Tuberculosis is a widespread disease all over the world. Early diagnosis plays a crucial role in the treatment of patients and can reduce the mortality rate. A new biosensor based on a binary photonic crystal is designed for the detection of mycobacterium tuberculosis bacteria in the blood. The structure air/(A/B)N/(Defect)/(A/B)N/air is employed, where A, B and N are the first and second layers and the number of periods, respectively. Layers A and B are chosen as GaAs and BaF2, respectively. The defect layer is the blood sample. The transfer matrix method (TMM) is utilized to simulate the structure. Some parameters, such as central wavelength, defect layer thickness and incident angle are optimized to maximize the sensitivity. The optimum sensitivity is found 3197.18 nm/RIU, which is extremely high when compared to the most recent papers published in this field. In addition, our sensor has a simple design, tunable fabrication and low cost and can be useful for the detection of many
organisms that can exist in the blood