82 research outputs found

    A Valid and Reliable Instrument for Cognitive Complexity Rating Assignment of Chemistry Exam Items

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    The design and use of a valid and reliable instrument for the assignment of cognitive complexity ratings to chemistry exam items is described in this paper. Use of such an instrument provides a simple method to quantify the cognitive demands of chemistry exam items. Instrument validity was established in two different ways: statistically significant correlations between expert-based cognitive complexity ratings and student performance (as measured through statistical difficulty of items), and statistically significant correlations between expert-based cognitive complexity ratings and student mental effort ratings. Key benefits associated with instrument use include an enhanced understanding of the cognitive complexity of chemistry assessment tasks and as a means for characterizing exam content for the measurement of cognitive development

    Water Collection from Air Humidity in Bahrain

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    The Kingdom of Bahrain falls geographically in one of the driest regions in the world. Conventional fresh surface water bodies, such as rivers and lakes, are nonexistent and for water consumption, Bahrain prominently relies on the desalination of sea water. This paper presents an ongoing project that is being pursued by a group of student and their advising professors to investigate the viability of extracting water from air humidity. Dehumidifiers have been utilized as water extraction devices. Those devices have been distributed on six areas that were selected based on a rigorous geospatial modeling of historical meteorological data. The areas fall in residential and industrial neighborhoods that are located in the main island and the island of Muharraq. Water samples have been collected three times every week since May of 2016 and the collection process will continue until May of 2017. The collected water samples have been analyzed against numerous variables individually and in combinations including: amount of water collected per hour versus geographical location, amount of water collected per hour versus meteorological factors, suitability of collected water for potable human consumption, detection of air pollution in the areas of collection and the economy of this method of water collection in comparison to other nonconventional methods. An overview of the completed analysis results is presented in this paper

    Water Collection from Air Humidity in Bahrain

    No full text
    The Kingdom of Bahrain falls geographically in one of the driest regions in the world. Conventional fresh surface water bodies, such as rivers and lakes, are nonexistent and for water consumption, Bahrain prominently relies on the desalination of sea water. This paper presents an ongoing project that is being pursued by a group of student and their advising professors to investigate the viability of extracting water from air humidity. Dehumidifiers have been utilized as water extraction devices. Those devices have been distributed on six areas that were selected based on a rigorous geospatial modeling of historical meteorological data. The areas fall in residential and industrial neighborhoods that are located in the main island and the island of Muharraq. Water samples have been collected three times every week since May of 2016 and the collection process will continue until May of 2017. The collected water samples have been analyzed against numerous variables individually and in combinations including: amount of water collected per hour versus geographical location, amount of water collected per hour versus meteorological factors, suitability of collected water for potable human consumption, detection of air pollution in the areas of collection and the economy of this method of water collection in comparison to other nonconventional methods. An overview of the completed analysis results is presented in this paper

    Pattern of Vascular Involvement in Egyptian Patients with Budd-Chiari Syndrome: Relation to Etiology and Impact on Clinical Presentation

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    Introduction and aim. Budd-Chiari syndrome (BCS) is caused by hepatic venous outflow obstruction. This work aims to analyze the pattern of vascular involvement in Egyptian patients with BCS, demonstrates its relation to etiology and shows its impact on clinical presentation.Material and methods. The current retrospective study was conducted at The Tropical Medicine Department, Ain Shams University on one hundred Egyptian patients with confirmed diagnosis of primary BCS who were presented to the Budd-Chiari Study Group (BCSG) from April 2014 to May 2016 by collecting clinical, laboratory and radiological data from their medical records.Results. Isolated hepatic vein occlusion (HVO) was the most common pattern of vascular involvement (43%), followed by combined HVO and inferior vena cava (IVC) compression by enlarged caudate lobe (32%), then combined HVO and IVC stenosis/webs (21%), and lastly isolated IVC occlusion (4%). Ascites was more significantly encountered in BCS patients with HVO than in those with isolated inferior vena cava (IVC) occlusion and patent HVs (P = 0.005). Abdominal pain was significantly encountered in patients with occluded three major HVs (P = 0.044). Behcet’s disease was significantly detected in isolated IVC occlusion. Protein C deficiency was significantly detected in patients with combined HVO and IVC compression.Conclusion. Isolated HVs occlusion was the most common pattern of vascular involvement in Egyptian patients with primary BCS. Vascular pattern of involvement affected the clinical presentation and was related to the underlying thrombophilia in those patients

    The Utility of Iron Chelators in the Management of Inflammatory Disorders

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    Since iron can contribute to detrimental radical generating processes through the Fenton and Haber-Weiss reactions, it seems to be a reasonable approach to modulate iron-related pathways in inflammation. In the human organism a counterregulatory reduction in iron availability is observed during inflammatory diseases. Under pathological conditions with reduced or increased baseline iron levels different consequences regarding protection or susceptibility to inflammation have to be considered. Given the role of iron in development of inflammatory diseases, pharmaceutical agents targeting this pathway promise to improve the clinical outcome. The objective of this review is to highlight the mechanisms of iron regulation and iron chelation, and to demonstrate the potential impact of this strategy in the management of several acute and chronic inflammatory diseases, including cancer
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