Oalib search

标题关键字摘要作者全部

显示搜索

我的图书馆

OALib Journal期刊

ISSN: 2333-9721

费用：99美元

投稿

时间不限

( 2673 )

( 2672 )

( 2454 )

( 2208 )

自定义范围…

匹配条件： “Georges M. El-Mollayess” ，找到相关结果约495817条。
列表显示的所有文章，均可免费获取

第1页/共495817条

每页显示条

Exogenous Endophthalmitis in Diabetic Patients: A Systemic Review
Georges M. El-Mollayess,Joanna S. Saadeh,Haytham I. Salti
ISRN Ophthalmology , 2012, DOI: 10.5402/2012/456209

Abstract:

保存相关文章

Exogenous Endophthalmitis in Diabetic Patients: A Systemic Review
Georges M. El-Mollayess,Joanna S. Saadeh,Haytham I. Salti
ISRN Ophthalmology , 2012, DOI: 10.5402/2012/456209

Abstract: Diabetes mellitus is a systemic disease that increases the risk of infections. Exogenous endophthalmitis is an inflammatory disease to which diabetic patients are more predisposed to than nondiabetic patients undergoing any intraocular intervention. This might be because of the change in the immune and inflammatory factors that intervene in wound healing and in the bacterial flora of the ocular adnexa. We conducted a literature review to assess the risk of exogenous endophthalmitis in diabetic patients undergoing cataract extraction, pars plana vitrectomy, and intravitreal injections and to check whether its treatment differ from in non-diabetics. We found that diabetic patients are more predisposed to virulent organisms and that the incidence of ophthalmic symptoms was not substantially different in diabetic versus nondiabetic patients. Regarding treatment, all patients with light perception should receive pars plana vitrectomy, while those with hand motion and better vision should be given an intravitreal antibiotics injection. Some authors recommend vitrectomy to diabetic patients with even counting figure vision. 1. Introduction Infectious endophthalmitis is defined as the infestation of the intraocular compartment by microorganisms. It represents one of the most severe and potentially devastating inflammatory reactions seen in the eye and it often results in irreversible visual loss [1, 2]. Based on the site of entry of this agent, endophthalmitis can be divided into an infection of either exogenous or endogenous origin. While the former condition most commonly occurs after intraocular surgery or trauma, the latter form is believed to be linked to septicemia. Postoperative bacterial endophthalmitis is a rare, but severe complication of intraocular surgery. The infecting bacteria by replication and release of toxins can damage the intraocular structures, and the inflammatory reaction of the host seems to contribute even further to the damage [3]. Patients with diabetes mellitus (DM) known to have an impaired immune response may be at a higher risk for developing postoperative infections. Effectively at the cellular and humoral levels, there is suboptimal response to different antigens in addition to altered phagocytic capabilities [4–7]. Moreover, it is established that impaired neutrophil bactericidal function is strongly associated with poor glycemic control [8, 9]. Furthermore, the tear film, the first immunological barrier for the ocular system, is altered in patients with DM. There is documented decrease in the breakup time and an established

保存相关文章

Crystal Growth, Structural and Optical Studies of CuGa₃Se₅ Bulk Compounds [PDF]
Dayane Habib, Georges El Haj Moussa
World Journal of Condensed Matter Physics (WJCMP) , 2016, DOI: 10.4236/wjcmp.2016.61004

Abstract: Bulk materials were synthesized by the Bridgman technique using the elements Cu, Ga, Se. These samples were characterized by Energy Dispersive Spectrometry (EDS) to determine the elemental composition, as well as by X-ray diffraction for structure, hot point probe method for type of conductivity. Optical response (Photoconductivity) and Photoluminescence (PL) and PL-excitation (PLE) at temperatures from 4.2 to 77 K were also used to estimate the band-gap energy of Cu-Ga₃Se₅. They show a nearly perfect stoechiometry and present p-type conductivity. CuGa₃Se₅ either have an Ordered Defect Chalcopyrite structure (ODC), or an Ordered Vacancy Chalcopyrite structure (OVC). The gap energy obtained by Photoconductivity and Photoluminescence (PL) for the different samples is 1.85 eV. Studying the variation of the gap as a function of the temperature shows that the transition is a D-A type. The defects that appear are probably Ga_Cu.

保存相关文章

Spectroscopic Ellipsometry Study of the Dielectric Function of Cu(In_1–xGa_x)₃Se₅ Bulk Compounds: Identification of Optical Transitions [PDF]
Dayane Habib, Georges El Haj Moussa
World Journal of Condensed Matter Physics (WJCMP) , 2017, DOI: 10.4236/wjcmp.2017.74009

Abstract: Using Spectroscopic Ellipsometry (SE), the optical properties of Cu(In_1−xGa_x)₃Se₅ bulk compounds, grown by the Bridgman method, were analyzed by varying x composition (0 ≤ x ≤ 1). Energy levels above the gap in the band scheme were determined by measuring the complex dielectric function $\"\"$ ？at room-temperature for energies between 1.5 and 5.5 eV using a variable angle of incidence ellipsometer. The transitions values E₁, E₂ and E₃ were observed above the gap for different samples of Cu(In_1−xGa_x)₃Se₅ alloy. When a gallium atom replaces an indium atom, one assumes globally that the levels related to selenium and copper are unchanged. Conversely, the levels corresponding to the conduction band are shifted towards higher energies. Thus, the gap increases as the composition of gallium increases. Spectroscopic Ellipsometry (SE) gave evidence for the interpretation of the choice of gap values which were compatible with that obtained from solar spectrum. Several other characterization methods like Energy Dispersive Spectrometry (EDS), hot point probe method, X-ray diffraction, Photoluminescence (PL), Optical response (Photoconductivity) were presented in this paper. The Cu(In_1−xGa_x)₃Se₅ have an Ordered Vacancy Chalcopyrite-type structure with lattice constants varying as a function of the x composition. The band gap energy of Cu(In_1−xGa_x)₃Se₅ compounds is found to vary from 1.23 eV to 1.85 eV as a function of x.

保存相关文章

Identification of Optical Transitions by Spectroscopic Ellipsometry (SE) on CuIn₃Se₅ Bulk Compounds [PDF]
Dayane Habib, Georges El Haj Moussa
World Journal of Condensed Matter Physics (WJCMP) , 2017, DOI: 10.4236/wjcmp.2017.74010

Abstract: Bulk materials were synthesized by the Bridgman technique using the elements Cu, In and Se. These samples were characterized by Energy Dispersive Spectrometry (EDS) to determine the elemental composition, as well as by X-ray diffraction for structure, hot point probe method for type of conductivity, Optical response (Photoconductivity) and Photoluminescence (PL) to determine the band gap value and Spectroscopic Ellipsometry to find energy levels above the gap in the band scheme at room-temperature. They show a nearly perfect stoechiometry and present a p-type conductivity. CuIn₃Se₅ either has a Stannite structure, an Ordered Defect Chalcopyrite structure (ODC), or an Ordered Vacancy Chalcopyrite structure (OVC). The gap energy obtained for the different samples was 1.23 eV. Energy levels above the gap in the band scheme were determinate by measuring the dielectric function at room temperature for energies lying between 1.5 and 5.5 eV. Many transitions were observed above the gap for different samples. Spectroscopic Ellipsometry gave evidence for the interpretation of the choice of gap values which were compatible with that obtained from solar spectrum.

保存相关文章

Diet, Genetics, and Disease: A Focus on the Middle East and North Africa Region
Akl C. Fahed,Abdul-Karim M. El-Hage-Sleiman,Theresa I. Farhat,Georges M. Nemer
Journal of Nutrition and Metabolism , 2012, DOI: 10.1155/2012/109037

保存相关文章

Abstract: The Middle East and North Africa (MENA) region suffers a drastic change from a traditional diet to an industrialized diet. This has led to an unparalleled increase in the prevalence of chronic diseases. This review discusses the role of nutritional genomics, or the dietary signature, in these dietary and disease changes in the MENA. The diet-genetics-disease relation is discussed in detail. Selected disease categories in the MENA are discussed starting with a review of their epidemiology in the different MENA countries, followed by an examination of the known genetic factors that have been reported in the disease discussed, whether inside or outside the MENA. Several diet-genetics-disease relationships in the MENA may be contributing to the increased prevalence of civilization disorders of metabolism and micronutrient deficiencies. Future research in the field of nutritional genomics in the MENA is needed to better define these relationships. 1. Introduction Over the past few decades, the MENA has been witnessing significant changes in food habits paralleled by an important preponderance of metabolite-related diseases. In a region whose traditional diet is known to be healthy due to high vegetable proteins, fibers, minerals, and vitamins with low content of unfavorable food products, the “industrialization/westernization of the diet” is a well-studied and documented phenomenon [1–3]. The MENA has been losing its traditional diet which was distinguished by its diversity and richness in raw foods, proteins, and multivitamins, in the favor of a more industrial diet which consists of increased preprocessed foods, sugars, fats, alcohol, animal products, saturated- and trans-fatty acids, and relatively less vitamins and minerals with decreased consumption of milk, fruits, and vegetables [4]. A big part of this change is attributed to the lifestyle changes and globalization with the invasion of western fast food to the MENA countries. Dietary choices, minimum physical activity, religious habits, consumer ignorance, high population growth rates, economic factors, and lack of both protection laws and food fortification programs are other critical factors that influence the nutritional status in the region [5]. These changes in dietary and lifestyle patterns contribute to an increase in the rates of micronutrients deficiencies, diet-related chronic diseases, and obesity in all groups of the population in the region [5]. Due to this grave impact on chronic diseases, diet became a target of public health initiatives that aim at restoring the traditional diet of

保存相关文章

Fabrication, Characterization and Optical Properties of CuIn₃Se₅ Bulk Compounds [PDF]
Dayane Habib, Ouloum Aoudé, Slyman Karishy, Georges El Haj Moussa
World Journal of Condensed Matter Physics (WJCMP) , 2015, DOI: 10.4236/wjcmp.2015.53021

Abstract: The present work prepared the CuIn₃Se₅ ingots by using a horizontal Bridgman method and investigated the Energy Dispersive Spectrometry (EDS) and X-Ray Diffraction (XRD) to calculate the compositions of the ingots. Photoluminescence was used to check their optical properties. It was found that CuIn₃Se₅ had either a Stanite structure, an Ordered Defect Chalcopyrite (ODC) structure, or an Ordered Vacancy Chalcopyrite (OVC) structure. The gap energy obtained by Photoluminescence (PL) for the different samples is 1.23 eV. Studying the variation of the gap as a function of the temperature shows that the transition is a D-A type.

保存相关文章

Overview of Boost Converters for Photovoltaic Systems [PDF]
Saleh E. Babaa, Georges El Murr, Faisal Mohamed, Srilatha Pamuri
Journal of Power and Energy Engineering (JPEE) , 2018, DOI: 10.4236/jpee.2018.64002

Abstract: DC-DC boost power converters play an important role in solar power systems; they step up the input voltage of a solar array for a given set of conditions. This paper presents an overview of the variance boost converter topologies. Each boost converter is evaluated on its capability to operate efficient, size, and cost of implementation. Conventional boost converter and interleaved boost converter are widely used topologies in photovoltaic systems reported; however, they have negative sides of varied efficiency level under changed weather conditions. Therefore, this paper proposes, interleaved boost converter with novel switch adaptive control, to maximise efficiency of standalone photovoltaic system under change of solar power levels, due to illadation condition.

保存相关文章

Health, environmental, and economic costs from the use of a stabilized diesel/ethanol mixture in the city of S？o Paulo, Brazil
Miraglia, Simone Georges El Khouri;
Cadernos de Saúde Pública , 2007, DOI: 10.1590/S0102-311X2007001600016

Abstract: in greater metropolitan s？o paulo, brazil, fossil fuel combustion in the transportation system is a major cause of outdoor air pollution. air quality improvement requires additional policies and technological upgrades in fuels and vehicle engines. the current study thus simulated the environmental and social impacts resulting from the use of a stabilized diesel/ethanol mixture in the bus and truck fleet in greater metropolitan s？o paulo. the evaluation showed reductions in air pollutants, mainly pm10, which would help avert a number of disease events and deaths, as estimated through dose-response functions of epidemiological studies on respiratory and cardiovascular diseases. valuation of the impacts using an environmental cost-benefit analysis considered operational installation, job generation, potential carbon credits, and health costs, with an overall positive balance of us$ 2.851 million. adding the estimated qualitative benefits to the quantitative ones, the project's benefits far outweigh the measured costs. greater metropolitan s？o paulo would benefit from any form of biodiesel use, producing environmental, health and socioeconomic gains, the three pillars of sustainability.

保存相关文章

第1页/共495817条

每页显示条