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CdSe/ZnSe Quantum-Dot Semiconductor Optical Amplifiers
Muaffak A. Al-Mossawi,Ali Gehad Al-Shatravi,Amin H. Al-Khursan
Insciences Journal , 2012,
Abstract: CdSe/ZnSe quantum dot semiconductor optical amplifier is studied theoretically where the core/shell structure is discussed. Absorption and emission coefficients and noise figure are studied. The emission coefficient obtained is higher than the similar structure of InGaAs/InP. A 25dB gain is obtained. A low noise figure (5.5dB) is obtained. A high output power can be obtained. The simulated structure can be used to develop photonic integrated circuits.
丝网印刷选择离子电极测定药物试剂中的氢溴酸西酞普兰
Tamer,Awad,Ali,Gehad,G.,Mohamed,A.,M.,Al-Sabagh,M.,A.,Migahed
分析化学 , 2014, DOI: 10.3724/SP.J.1096.2014.30518
Abstract: 以四硼酸钾（KTpClPB）离子载体（电极V）和西酞普兰磷钨酸（cp-pt）离子对混合物（电极X）作为丝网印刷电极的电活性物质、磷酸三甲苯酯（TCP）作为溶剂中介，制备并表征了一种新型丝网印刷离子选择电极。利用此电极测定药剂中的西酞普兰，在4.90×10-7-1.0×10-2（电极V）和1.0×10-6-1.0×10-2mol/L（电极X）浓度范围内呈一近似-Nernstain响应，斜率分别为60.47±0.80和59.93±1.45mV/decade，检出限分别为0.49和1.0μmol/L。电极具有响应快、重复性好、稳定性高（电极V：5个月，电极X，4个月）、宽pH值适应范围（电极V：2-9，电极X，2-8）以及良好的选择性等特点，可应用于测定尿液和血清中的西酞普兰。
The Epistemic Oppression of the Veil  [PDF]
Gehad Abdelal
Open Journal of Social Sciences (JSS) , 2017, DOI: 10.4236/jss.2017.59001
Abstract: The veil is one of the essential phenomena in the Islamic world. Many Islamic and western feminist studies analyzed the veil. The Islamic feminism considers the veil as a free choice and a representation of the Islamic identity. On the other hand, one group of the feminism of the West counts the veil as oppression and a threat to the western modernity. However, both studies tackle the veil issue from the framework of free choice and identity without enough analyzing to the epistemological framework that surrounds it. Therefore, this paper investigates the epistemic oppression of the veil in the Islamic world by examining the claim of “the veil is a free choice”. The study will result in three situations of re-situatedness to the right-wing, external re-situatedness and re-situatedness to contrary epistemic system. These outcomes could refute the claim that the veil could be analyzed through the free choice structure, whether it is oppression or a gift.
Redefining Technology Role in Education  [PDF]
Ali S. Al Musawi
Creative Education (CE) , 2011, DOI: 10.4236/ce.2011.22018
Abstract: The paper is a conceptual attempt to explore the new roles of technology in education which has increasingly become more than a sole medium, as was its description in the past. Basically, the key idea is that technology, with the powers of ICT, in education has now three main roles, namely: a medium/resource, a management, and a delivery. These new roles, when combined, could set the stage for restructuring the education institutions in an innovative way that leaves the current education system in history.
Calcium Composition and Microstructure of Coral Stylophora pistillata under Phosphate Pollution Stress in the Gulf of Aqaba  [PDF]
Ali Al-Sawalmih
Natural Science (NS) , 2016, DOI: 10.4236/ns.2016.83012
Abstract: Corals and coral-reef ecosystems have been known to be extremely sensitive to environmental pollution, which effects on growth and calcification of their skeletons. Diffused phosphate dust during loading and shipment in seawater was found to cause serious impacts on corals by inhibiting calcification in their skeletons. Calcium concentrations in cultured fragments of coral Stylophora pistillata from Phosphate Terminal (PT) site in the Jordanian Gulf of Aqaba were investigated and compared with fragments from the same colony cultured in the Marine Science Station (MSS) site as marine protected area. Energy Disperse X-rays (EDX) spectroscopy and Scanning Electron Microscopy (SEM) were employed to determine the elemental composition of coral fragments and identify their microstructural characteristics, respectively. EDX results showed that coral samples from the Phosphate Terminal (PT) site were poorly mineralized with significantly low concentrations of calcium which were only about 12% of those from the MSS control site. Moreover, higher amounts of O and C in the elemental analysis of corals from the PT site indicated domination of organic matrix content in their skeleton which is typical for corals under phosphate pollution stress. This result was in accordance with the SEM images of the PT samples which exhibited alteration in their microstructure morphology resembling organic matrix as a major constituent, unlike the SEM images from the MSS protected area. These results strongly suggest that phosphate dust which is diffused during exportation through loading and shipping in the Gulf of Aqaba has adverse impacts on corals and marine ecosystem through decreasing calcium mineralization in their skeletons.
Stripping Voltammetric Determination of Timolol Drug in Pharmaceuticals and Biological Fluids  [PDF]
Ali F. Al-Ghamdi
American Journal of Analytical Chemistry (AJAC) , 2011, DOI: 10.4236/ajac.2011.22020
Abstract: A sensitive and reliable stripping voltammetric method was developed to determine timolol drug. This method is based on the adsorptive accumulation of the drug at a hanging mercury drop electrode (HMDE) and then a negative sweep was initiated, which yield a well defined cathodic peak at –850 mV versus (Ag/AgCl) silver reference electrode. To achieve high sensitivity, various experimental and instrumental variables were investigated such as supporting electrolyte, pH, accumulation time and potential, scan rate, frequency, pulse amplitude, convection rate and working electrode area. The monitored adsorptive current was directly proportional to the concentration of timolol and it shows a linear response in the range from 1 × 10–7 to 1.5 × 10–6 mol●l–1 of this drug (correlation coefficient = 0.998) and the detection limit (S/N = 3) is 1.26 × 10–9 mol●l–1 at an accumulation time of 30 sec. The developed adsorptive stripping voltammetry (AdSV) procedure shows a good reproducibility, the relative standard deviation RSD% (n = 8) at a concentration level of 1 × 10–6 mol●l–1 of timolol was 0.13%, whereas the method accuracy was indicated via the mean recovery of 110% ± 1.414%. Possible interferences by several substances usually present in the pharmaceutical formulations have been also evaluated. The applicability of this approach was illustrated by the determination of the drug in pharmaceutical preparation and biological fluids such as serum and urine.
Pattern of Thyroid Cancer in the Eastern Province of Saudi Arabia: University Hospital Experience  [PDF]
Ali M. Al-Amri
Journal of Cancer Therapy (JCT) , 2012, DOI: 10.4236/jct.2012.33027
Abstract: Objectives: To review the pattern of thyroid tumor, demographic data of the patients, sensitivity, and specificity of fine needle aspiration cytology; Materials and Methods: This is a retrospective analysis of patients who underwent total or near-total thyroidectomy at King Fahad Hospital of the University between 1982 and 2008. Data were analyzed for demographic characteristics, type of thyroid tumors, Fine Needle Aspirations Cytology (FNAC) yields and surgical complications; Results: A total of 143 patients with thyroid tumors underwent throidectomy. Their median age was 37.5 years. Females were predominantly affected (81%) with female to male ratio of (4:29). Thyroid carcinoma accounted for (75%) while benign tumors for (25%). The most common thyroid epithelial cancer was papillary type (74%) and was limited to thyroid tissues in almost two third of cases. Non-epithelial cancer in the form of thyroid lymphoma accounted for (4.89%) of the cases. FNAC sensitivity was 56% and specificity 92%. Surgical complications occurred in 18% of the patients; Conclusions: The commonest malignant thyroid cancer was papillary carcinoma. Thyroid cancer was more common in females. FNAC is highly accurate to confirm thyroid cancer but less sensitive in this study. Surgical complications were relatively minimal.
Lethal time at different temperatures and date variety preference of the saw-toothed grain beetle in stored dates  [PDF]
Mohammad Ali Al-Deeb
Agricultural Sciences (AS) , 2012, DOI: 10.4236/as.2012.36095
Abstract: This electronic document is a “live” template. The various The saw-toothed grain beetle, Oryzaephilus surinamensis (L.) (Coleoptera: Silvanidae), is the most important insect pest attacking stored dates in the United Arab Emirates. We sought to determine the time required to cause 100% mortality (lethal time) in O. surinamensis adults incubated at different temperatures, to measure temperature penetration time inside a date mass, and to study date variety preference of O. surinamensis adults. To do this, adults of O. surinamensis were separately incubated at -22℃, 50℃, and 55℃, for 5, 10, 20, 30, 60, 90, and 120 min, per temperature treatment; and we used feeding choice tests on four date varieties (Khelas, Fardh, Lulu, and BuMaán). Results showed that the lethal times of O. surinamensis adults, incubated at -22℃, 50℃, and 55℃, without dates, were 5, 10, and 20 min, respectively; while they were several times higher (30, 90, and 120 min, respectively) in the presence of dates. Results also showed that bigger date masses required either more heating or more freezing time to reach lethal temperatures. We found Khelas to be the least preferred date variety. Future studies should evaluate if heat and chilling injury affect postharvest date quality.
Identity and Mobility in a Digital World  [PDF]
Ali M. Al-Khouri
Technology and Investment (TI) , 2013, DOI: 10.4236/ti.2013.41002
Abstract:

Mobile identity management has attracted the attention of both the public and private sectors in the last few years. In the context of service delivery, modern mobile communication networks offer more convenient approaches to developing citizen-centric applications. However, taking into consideration the need for compelling user authentication and identification, secure communication in mobile environments remains a challenging matter. This article explores the potential role of government-issued smart identity cards in leveraging and enabling a more trusted mobile communication base. It delves into the identity management infrastructure program in the United Arab Emirates (UAE) and how the smart identity card and overall system architecture have been designed to enable trusted and secure transactions for both physical and virtual mobile communications.

Triggering the Smart Card Readers Supply Chain  [PDF]
Ali M. Al-Khouri
Technology and Investment (TI) , 2013, DOI: 10.4236/ti.2013.42008
Abstract:

In the last 12 years or so, many governments have launched modern identity management systems. These systems typically integrate a set of advanced and complex technologies to provide identification and authentication capabilities. The major output of such systems is smart identity cards that bind the cardholders’ identities to their biographical data and one or more biometric characteristics. The field of government practice has been focusing on the enrolment capabilities and infrastructure rollout, with little focus on smart card applications in the public domain. This article attempts to address this area in the body of knowledge from a government view point. It explores card reader adoption opportunities in both the public and private sectors, and attempts to outline the United Arab Emirates’ (UAE’s) government’s plans to disseminate card readers and promote their adoption in government and various industrial groups in the country.

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