2,044 research outputs found

    Assessment of Natural and Anthropogenic Environmental Effects in the Costal Areas between Abu Dhabi and Dubai – Application of Remote Sensing

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    The present work represents an attempt to detect changes induced by both natural and anthropogenic activities to the coastal area extending between the cities of Abu Dhabi and Dubai, United Arab Emirates. This area is dominated by islands, bars, tidal channels and embayment regimes and flanked by coastal sabkhas that give way to the great sand dunes, which represent an extension of the Empty Quarter desert. The area is also characterized by the existence of many aquatic systems such as coral reefs and the oolitic shoals around Abu Dhabi city. It was the site of many human activities in the pre-oil era, such as pearl diving. During the last three decades, the study area has witnessed deep and widespread changes as part of the urbanization process that has impacted the whole United Arab Emirates. Examples of such activities include coastal modification, large scale construction, oil well drilling and many other similar activities, some of which are really big in scale. Such activities have affected significantly the components of the natural ecosystems as well as the physical and chemical properties of the area, including its geomorphology and topography. In the study, some of these changes were traced and detected using remote sensing and direct visual observation, such as ground truthing where ever possible. The study focused on visual analysis mainly due to the scarcity of old data from the pre-oil era. However, wherever possible a quantitative approach was attempted when data was available. Maj or changes in the studied area are in the form of large scale urbanization in residential, commercial and industrial development of both continental and aquatic environments. Some of these are of a drastic scale and have affected significantly the pristine environment. These changes were detected and contrasted from the available images and then documented using ground photography. In some cases, vector layers were extracted and superimposed to give an idea about the extent of such changes. Such studies are essential to document the baseline environmental and man-made environmental components and to trace changes over time. These studies should be part of the future coastal management in the United Arab Emirates

    Fire Resistance of Loadbearing LSF Assemblies

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    This paper presents an analytical thermal-structural model for loadbearing lightweight steel framed (LSF) walls exposed to fire on one side. The model reflects temperature and deformation data from six standard fire resistance tests conducted recently by the National Research Council of Canada in partnership with the North American steel industry. Some characteristic patterns in thermal transmission and structural behaviour are discussed. Temperature histories across LSF assemblies are simulated numerically by explicit integration of transient heat transfer equations. The apparent thermal properties are calibrated for gypsum board and three types of insulation. Analytical procedures are presented to simulate lateral deformation histories and predict structural failure times. The model illustrates how different heating regimes in cold formed steel studs cause different structural failure modes

    An unusual metastatic site of head and neck cancer; Case Report and literature review

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    The annual occurrence of Head and Neck caner (HNC) is documented to be more than 650,000 cases with 330,000 deaths. In the United States, it represents 3% of all malignancies and affects 53,000 Americans. Metastasis to the lung, liver and bones are considered the most common locations. Herein, We are reporting a case of HNC and an unusual synchronous gastric metastasis found on an upper gastrointestinal endoscopy (EGD) after CECT scanning of Abdomen shows only the mass that related to stomach fundus and MRI pelvic no mass could be seen. Both cancers were poorly differentiation on histopathology, which raises the flag of possible disease aggressiveness and poor treatment respons

    Direct Enantiomeric Resolution of Betaxolol with Application to Analysis of Pharmaceutical Products

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    A high-performance liquid chromatographic (HPLC) method has been developed for the separation and determination of S- and R-enantiomers of betaxolol in tablets and ophthalmic preparations. Baseline resolution was achieved by using teicoplanin macrocyclic antibiotic chiral stationary phase (CSP) known as Chirobiotic T with fluorescence detection at excitation/emission wavelengths 275/305 nm. The polar ionic mobile phase (PIM) consists of methanol-glacial acetic acid-triethylamine, (100:0.020:0.025, v/v/v) has been used at a flow rate of 1.5 ml/min. All analytes with S-(–)-atenolol as internal standard were conducted at ambient temperature. The method is highly specific where another coformulated compounds did not interfere. The stability of betaxolol enantiomers under different degree of temperature also studied. The results showed that it is stable for at least 7 days at 70°C. The method validated for its linearity, accuracy, precision and robustness. Experimental design was used during validation to evaluate method robustness. Using the chromatographic conditions described, S- and R-betaxolol were well resolved with mean retention times of 11.3 and 12.6 min, respectively. Linear response (r > 0.997) was observed over the range of 10–500 ng/ml of betaxolol enantiomers, with detection limit of 5 ng/ml. The recoveries of S- and R-betaxolol from tablets and ophthalmic preparation ranged from 97.4 to 101.4% and 98.0 to 102.0%, respectively. The mean relative standard deviation (R.S.D.%) for both enantiomers were 1.1–1.4% and 1.3–1.7% in tablets and ophthalmic solution, respectively

    Predictive factors for nutritional behavior among pregnant women attending antenatal care clinic in 6th of October City

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    Background: Good maternal nutrition during pregnancy is important to ensure health for the mother and the fetus. This study aimed to assess nutritional knowledge and behavior among a group of Egyptian pregnant women in addition to identify the factors influencing their nutritional behavior. Methods: This comparative cross sectional study included 300 pregnant women attending the antenatal care clinics in 6th of October University private hospital and El-Hosary primary healthcare (PHC) unit. The data was collected through a modified nutritional survey that was translated from Spanish to Arabic and revised by language experts for clarity.  Results: Almost all of the women attending the private hospital were university educated while about half of the women attending the PHC unit were graduated from technical education. In general, the level of knowledge about food requirements of both groups was satisfactory good; however, neither of them fulfilled the WHO recommendations of food intake during pregnancy or the optimum number of meals per day. The average random blood glucose was higher among the women attending the PHC unit; the BMI, mid arm circumference and subcutaneous fat were higher among the same group as well. In regard to fulfilling the WHO recommended servings per day, only starch and fat items were fulfilled by both groups, whereas the other three items (vegetables, fruits, meat and dairy products) were merely included in the diets of both groups. Conclusion: Healthy behavior among pregnant women in both group were influenced by their educational level, occupation as well as their pre-gestational BMI. Those were the only three significant predictive factors, where women with higher education showed an active lifestyle. In addition, women starting with normal BMI before pregnancy had better healthy behaviors including the choice of healthy diets

    INVESTIGATION OF THE EFFECT OF TEMPERATURE AND TIME OF CASE HARDENING ON THE MECHANICAL PROPERTIES AND MICROSTRUCTURE OF LOW CARBON STEEL (AISI 1020)

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    The main objective of this paper is experimental study of pack carburizing of carbon steels (AISI 1020) by using two parameters (holding time and carburizing temperature). This study was conducted by using electrical furnace. This process is carried out at temperatures of 950°C for durations time 90 minutes. From the experiment, the surface hardness and thickness of carbon layer was different according to the parameters used. The quenching medium that uses in this experiment is water, oil, sea water and air. For carburizing temperature at 950°C, the highest of surface hardness value for air is 128 HV that carburized for 90 minutes, the highest of surface hardness value for water is 224 HV that carburized for 90 minutes. For carburizing temperature of 950°C, the highest of surface hardness value for sea water is 166.9 HV that carburized for 90 minutes and for carburizing temperature at 950°C which is the highest of surface hardness value for oil is 126 HV. The thickness of carbon layer was between 40μm to 120μm. The result indicates the carburizing process accelerates the diffusion of carbon atoms into the surface, thus increasing the thickness of carburized layer as well as the surface hardness

    Aorto-Uni-Iliac Stent Grafts with and without Crossover Femorofemoral Bypass for Treatment of Abdominal Aortic Aneurysms: A Parallel Observational Comparative Study

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    We investigated the safety and efficacy of primary aorto-uni-iliac (AUI) endovascular aortic repair (EVAR) without fem-fem crossover in patients with abdominal aortic aneurysm (AAA) and concomitant aortoiliac occlusive disease. 537 EVARs were implemented between 2002 and 2015 in University Hospital Galway, a tertiary referral center for aortic surgery and EVAR. We executed a parallel observational comparative study between 34 patients with AUI with femorofemoral crossover (group A) and six patients treated with AUI but without the crossover (group B). Group B patients presented with infrarenal AAAs with associated total occlusion of one iliac axis and high comorbidities. Technical success was 97% (n=33) in group A and 85% (n=5) in group B (P=0.31). Primary and assisted clinical success at 24 months were 88% (n=30) and 12% (n=4), respectively, in group A, and 85% (n=5) and 15% (n=1), respectively, in group B (P=0.125). Reintervention rate was 10% (n=3) in group A and 0% in group B (P=0.084). No incidence of postoperative critical lower limb ischemia or amputations occurred in the follow-up period. AUI without crossover bypass is a viable option in selected cases

    Prevalence of Toxigenic and Methicillin Resistant Staphylococci in Poultry Chain Production

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    oai:ojs.pkp.sfu.ca:article/1Staphylococci are a worldwide cause of human and animal infection and are considered to be of the most common causes of infections in birds. Enterotoxins produced by some staphylococcal species were recognized as a causative agent of staphylococcal food poisoning (SFP). Only enterotoxins produced by Staphylococcus aureus were as yet well characterized. Much less is known about enterotoxigenic potential of coagulase-negative species of genus Staphylococcus (CNS). It has been reported that enterotoxigenic CNS strains have been associated with human and animal infections and food poisoning. Samples collected from chicken production cycle (un hatched eggs, baby chicks, broilers, chicken meat and table eggs) in Luxor, Egypt were tested to investigate the presence of Staphylococcus species and detection of their enterotoxines genes with more special attention for detection of methicillin resistance gene (mec A). Samples were tested for S. aureus and CNS on the basis of cultural and biochemical properties and confirmed by PCR amplification of 16S rRNA and clfa gene. Results showed that the presence of Staphylococci were 50/150 (33.3%), 14% of the samples were S. aureus (21/150), while, 19.33% were CNS (29/150). mecA gene was detected in 66.7% and 51.7% among S. aureus and CNS respectively. Enterotoxins genes (seb, sec and see) were found in 5 (23.8%) of S. aureus with a percent of (9.5%) for seb and sec and (4.8%) for see, while sec and see were found in 6 (20.6%) of CNS.  With a percent (10.3%) for each. &nbsp

    A Case of Pure Matrix Ureteral Stone: A rare type of urinary calculi that may be overlooked

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    Matrix stones are a rare form of urinary calculi with a low mineral content. We report a 63-year-old female patient who presented to the Sohar Hospital, Sohar, Oman, in 2018 with unexplained left flank pain and constipation. She had a history of chronic renal failure (CRF) and had previously undergone haemodialysis (HD). Non-contrast computed tomography (CT) did not show any renal or urinary stones. However, a left-sided ureteroscopy revealed a yellow-coloured stone that was soft in consistency occupying the proximal 5 cm section of the ureter. Many attempts at forceps extraction were required for complete clearance. A global quantitative composition analysis revealed the extracted stone to be composed entirely of protein-matrix material. Matrix stones require a high index of suspicion as they are sometimes radiolucent and cannot be visualised on CT scans. Risk factors include being female and a history of urinary tract infections, CRF and HD.Keywords: Urolithiasis; Ureteral Calculi; Diagnostic Imaging; Ureteroscopy; Case Report; Oman

    Molecular Characterization of Biofilm Producing Genes in Salmonellae Isolated from Chicken

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    Salmonella enterica considered one of the most important food-borne pathogen. Biofilm formation considered one of the main problems related to S. enterica, in this study, biofilm formation, colony morphotype, cellulose and curli production genes of 19 Salmonella isolates were tested. The results showed that 85% of isolates produced strong biofilm and 15% of isolates produced moderate biofilm on polystyrene plate with 1/20 diluted TSB. Different colony morphotypes expressed saw, sbam, and rdar morphotype when cultivated on LB containing Congo red for monitoring cellulose and curli production. All S. enterica strains possess adrA, csgD and gcpA genes using PCR. Thus in this study all Salmonella isolates formed biofilm so they give increased tolerance for antimicrobial agents and disinfectant, which results in difficulty in the treatment of diseases and causing many problems in food industry as it becomes a persistent of source of contamination
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