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Value-added Impact of Geostationary Hyperspectral Infrared Sounders on Local Severe Storm Forecasts——via a Quick Regional OSSE

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Advances in Atmospheric Sciences 2018年第10期35卷 1217-1230页

作者： Zhenglong LI Jun LI Pei WANG Agnes LIM Jinlong LI Timothy J.SCHMIT Robert ATLAS sid-ahmed BOUKABARA Ross N.HOFFMAN Cooperative Institute for Meteorological Satellite Studies University of Wisconsin-Madison Center for Satellite Applications and Research NOAA Atlantic Oceanographic and Meteorological Laboratory OAR/NOAA Center for Satellite Applications and Research NOAA

Accurate atmospheric temperature and moisture information with high temporal/spatial resolutions are two of the key parameters needed in regional numerical weather prediction(NWP) models to reliably predict high-impact weather events such as local severe storms(LSSs). High spectral resolution or hyperspectral infrared(HIR) sounders from geostationary orbit(GEO) provide an unprecedented source of near time-continuous, three-dimensional information on the dynamic and thermodynamic atmospheric fields—an important benefit for nowcasting and NWP-based forecasting. In order to demonstrate the value of GEO HIR sounder radiances on LSS forecasts, a quick regional OSSE(Observing System Simulation Experiment)framework has been developed, including high-resolution nature run generation, synthetic observation simulation and validation, and impact study on LSS forecasts. Results show that, on top of the existing LEO(low earth orbit) sounders, a GEO HIR sounder may provide value-added impact [a reduction of 3.56% in normalized root-mean-square difference(RMSD)] on LSS forecasts due to large spatial coverage and high temporal resolution, even though the data are assimilated every 6 h with a thinning of 60 km. Additionally, more frequent assimilations and smaller thinning distances allow more observations to be assimilated, and may further increase the positive impact from a GEO HIR sounder. On the other hand, with denser and more frequent observations assimilated, it becomes more difficult to handle the spatial error correlation in observations and gravity waves due to the limitations of current assimilation and forecast systems(such as a static background error covariance). The peak reduction of 4.6% in normalized RMSD is found when observations are assimilated every 3 h with a thinning distance of 30 km.

关键词： OSSE hyperspectral sounder high-impact weather

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Incidence and Risk Factors of Acute Kidney Injury in ICU Patients of Omdurman Teaching Hospital

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Open Journal of Nephrology 2021年第1期11卷 43-57页

作者： Abdel Mumin sid ahmed Nusaiba Hassan Mohamed Eltahir Omdurman teaching Hospital Omdurman Khartoum State Sudan

Background: Acute kidney injury (AKI) is a common complication in critically ill patients and it is commonly associated with high mortality and morbidity with adverse short and long term outcome. Objectives: The main objective of this study was to determine the incidence of acute kidney injury in ICU patients in Omdurman teaching hospital, and to assess the risk factors associated with the development of acute kidney injury in a critically ill patient. We also intended to find out the impact of acute kidney injury on ICU outcomes. Methods: In this descriptive prospective, cohort hospital-based study, 211 patients were studied and followed up during admission in ICU from November 2019 until July 2020 in Omdurman teaching hospital. Results: 61 patients of the total 211 patients developed renal impairment during their stay in ICU. 64% (39 patients) were males and 36% (22 patients) were female, mean age was 41 ± 5, renal impairment developed after a mean of 5 days of admission and the most common cause was decreased level of consciousness and severe hypotension, sepsis accounting for 40% of the admission. The outcome in ICU showed that the mortality rate was high up to 41% in patients who developed acute kidney injury, Sepsis accounted for over 96% (24 patients) who have passed away. Conclusions: Development of AKI in ICU is an important risk factor for poor outcomes in critically setting. Prevention is the best method for avoiding AKI, with the early identification and recognition of high-risk patients.

关键词： Acute Kidney Injury ICU Risk Factors Outcome Frequency

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Blood Oxidant/Antioxidant Status in overfed Aging Rats: Comparative Effects of Sunflower and Olive-Linseed Mixture Oil Rich Diets

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Biomedical and Environmental Sciences 2013年第9期26卷 765-768页

作者： AYAD Amina MERZOUK Hafida MERZOUK sid ahmed NARCE Michel Laboratory of Physiology and Biochemistry of Nutrition Department of Biology Faculty of Natural and Life SciencesEarth and Universe University Abou-Bekr Belkad Department of technical sciences Faculty of Engineering University Abou-Bekr Belkad INSERM UMR 866 "Lipids Nutrition Cancer"University of Burgundy Faculty of Sciences 6 Boulevard Gabriel

Obesity, one of the most common health problems, is associated with glucose and lipid metabolism abnormalities, increased cardiovascular risk and oxidative stressI1}. Aging is also associated with an increase in oxidative stress[2]. Considering that older adults are already at risk for oxidant stress, the additional metabolic perturbations of obesity aggravated the susceptibility to oxidant stress. Modulating age-related oxidative stress via dietary interventions could reduce free radical production and significantly improve health in aging.

关键词： Comparative Effects of Sunflower and Olive-Linseed Mixture Oil Rich Diets Blood Oxidant/Antioxidant Status in overfed Aging Rats CAF PUFA

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On Leader Election in Multi-Agent Control Systems

On Leader Election in Multi-Agent Control Systems

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2010 Chinese Control and Decision Conference

作者： Theodor Borsche sid ahmed Attia Control Systems Group Berlin Institute of TechnologyBerlinGermany

ISBN: (纸本)9781424451814

＜正＞In this contribution,we discuss the election of an optimal leader out of a network of agents described by first integrator dynamics and running a consensus *** network of agents may be a group of autonomous robots or more generally communicating vehicles,and the target is,for instance,to move the formation to a new location.A leader is said to be optimal if it leads to a controllable network,and minimizes a quadratic cost of reaching a target for all the other agents of the *** the first part,controllability conditions and a decentralized way of checking them are *** then study the correlation between the value of a quadratic cost function measuring the leader performance and the network *** correlation is found between closeness and degree centrality indices of the agents and the cost of achieving the assigned *** allows us to run the optimal leader election process without a central authority and without the nodes having full knowledge of the network topology.

关键词： Consensus algorithms controllability multi-agent control systems leader election networked control systems centrality indices

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Vitamins C, E, and NADH on in Vitro Lymphocyte Proliferation and Redox Status among Obese Patients

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Food and Nutrition Sciences 2016年第12期7卷 1082-1098页

作者： Asmaa Meraou Hafida Merzouk Amel Saidi Amel Medjdoub sid ahmed Merzouk Slimane Belbraouet Laboratory of Physiology Physiopathology and Biochemistry of Nutrition Department of Biology Faculty of Natural and Life Sciences Earth and Universe University Abou-Bekr Belkaid of Tlemcen Tlemcen Algeria University Djilali liabes of sidi Bel Abbes Sidi Bel Abbes Algeria Department of Technical Sciences Faculty of Engineering University Abou-Bekr Belkaid of Tlemcen Tlemcen Algeria Ecole de Nutrition Université de Moncton Moncton Canada

Background: The prevalence of overweight and obesity associated with oxidative stress and immune abnormalities is continuously increasing. Antioxidant supplementations might counteract potential damage caused by ROS to cellular tissues. Objective: To determine the role of vitamins on immune improvement during obesity, we investigated in vitro effects of vitamins C, E, and NADH on mitogen-stimulated proliferation, Th1- and Th2-type cytokine production, and oxidant/antioxidant status of lymphocytes isolated from obese patients. Methods: Peripheral blood lymphocytes were isolated using a density gradient of Histopaque. They were in vitro cultured and stimulated by Con A in the presence or absence of vitamins. Cell proliferation was determined by MTT assay and interleukin-2, interleukin-4 and interferon-γ (INFγ) secretions. Cell oxidant/antioxidant balance was studied by assaying glutathione (GSH), malondialdehyde (MDA), carbonyl protein levels, catalase activity and micronucli frequency. Results: Obesity is associated with enhanced oxidative stress response. Indeed, vitamin C, E and NADH improved significantly lymphocyte proliferation and diminished cellular oxidative stress. Conclusion: Treatments of lymphocytes with vitamins had beneficial effects on lymphocyte proliferation, cytokines secretions and redox status, generating an anti-inflammatory profile and should be considered in therapeutic approaches for normalizing immune cell function in obesity.

关键词： Obesity Lymphocytes Vitamins Cytokines Oxidant/Antioxidant Status

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Cartography of Air Pollution in an Industrial City in North-Eastern Algeria by Using Two Indexes： Poleotolerance Index and Atmospheric Purity Index

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Journal of Life Sciences 2014年第1期8卷 95-100页

作者： Djamel Fadel ahmed Soufiane sid Nadla Zga Filali Latreche Abdelkarim Ouamer Ali Institute Agro-Veterinary Taoura Laboratory Life Science and Technology University of Mohamed Cherif Messaadia Route d 'Annaba 41000 Algeria Planning Department Laboratory of Natural Resources and Sustainable Development University of Annaba B.P/12 Annaba 23000 Algeria

Of all the methods of studies on bio-estimation of air pollution by lichen flora, the authors cannot justify a choice of one method over another. Consultation of previous work by researchers has allowed us to compare these methods and to better understand their strengths and limitations. Under the terms of estimating the pollution, these methods are classified into three categories. Some are qualitative, quantitative and others are finally some indirect methods. The methods used to assess the overall air pollution relative value for each station studied. As part of our work, the authors have chosen a quantitative approach based on the combination of two methods. They are based on pollution indices obtained from mathematical formulas based on various parameters related to the lichen flora. They are represented by the I.P. （index poleotolerance） and the I.A.P. （index of atmospheric purity） and these two indices allowed us to map of global air pollution in the city of Skikda and petrochemical industry as well as peri-urban areas （Haddaiek, Hamadi Krouma, Hamrouche Hamoudi, Larbi Ben M＇Hidi）. The authors have identified areas of iso-pollution around different emission centers represented by the largest petrochemical area, traffic and households in urban areas of Skikda, Hamadi Krouma, Hamrouche Hamoudi and Larbi Ben M＇Hidi.

关键词： Bio-diversity bio-indication lichenic flora pollution Algeria.

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Thermophotovoltaic Emitters Based on a One-Dimensional Metallic-Dielectric Multilayer Nanostructures

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Journal of Electronics Cooling and Thermal Control 2014年第1期4卷 39-48页

作者： Samah G. Babiker Shuai Yong Mohamed O. sid-ahmed Xie Ming Department of Engineering Thermophysics School of Energy Science and Engineering Harbin Institute of Technology Harbin China Department of Engineering Thermophysics School of Energy Science and Engineering Harbin Institute of Technology Harbin China Department of Physics Faculty of Education University of the Holy Quran and Islamic Science OmdurmanSudan Department of Physics Faculty of Sciences Sudan University of Science and Technology Khartoum Sudan

In this paper, a one-dimensional multilayer is optimized for potential applications as thermophotovoltaic (TPV) selective emitter. The proposed TPV emitter was fabricated through a magnetron sputtering process by using the radio frequency (RF) magnetron sputtering system. The spectral emittance of the proposed TPV emitter is measured by using spectral transmittance and reflectance measurement system at wavelength from 0.3 μm to 2.5 μm at near-normal incident 8。. The bidirectional reflectance distribution function BRDF is measured by three axis automated scatterometer (TAAS). The effect of the diffraction orders and plane of incidence on the spectral emittance of the proposed TPV emitter is calculated numerically by using the rigorous coupled-wave analysis (RCWA). The emittance spectrum of the proposed TPV selective emitter shows three close to unity emission peaks which are explained by the surface plasmon polariton (SPP), gap plasmon polariton (GPP) and magnetic polariton (MP) excitation. The results show that the proposed emitter has high emittance value in the spectral range of 0.69 emitter, if used as a selective emitter with a low band gap photovoltaic cell (GaSb), would lead to high TPV overall efficiency and high electrical output power.

关键词： Thermophotovoltaic Selective Emitter Rigorous Coupled Wave Analysis (RCWA) A Magnetron

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Effect of negative permittivity and permeability on the transmission of electromagnetic waves through a structure containing left-handed material

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Natural Science 2011年第4期3卷 328-333页

作者： Muin F. Ubeid Mohammed M. Shabat Mohammed O. sid-ahmed 不详

We investigate the characteristics of electromagnetic wave reflection and transmission by multilayered structures consisting of a pair of left-handed material (LHM) and dielectric slabs inserted between two semi-infinite dielectric media. The theoretical aspect is based on Maxwell's equations and matching the boundary conditions for the electric and magnetic fields of the incident waves at each layer interface. We calculate the reflected and transmitted powers of the multilayered structure taking into account the widths of the slabs and the frequency dependence of permittivity and permeability of the LHM. The obtained results satisfy the law of conservation of energy. We show that if the semi-infinite dielectric media have the same refractive index and the slabs have the same width, then the reflected (and transmitted) powers can be minimized (and maximized) and the powers-frequency curves show no ripple. On the other hand if the semi-infinite dielectric media have different values of refractive indices and the slabs have different widths, then under certain conditions the situation of minimum and maximum values of the mentioned powers will be reversed.

关键词： Electromagnetic Waves Left-Handed Materials Frequency Reflected and Transmitted Powers

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Genetical Crossbreeding Effect on the Zootechnical Performances of the Domestic Rabbit （Algeria） x Californian

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Journal of Life Sciences 2013年第2期7卷 165-170页

作者： Mefti Korteby Hakima Kaidi Rachid sid Sihem Boukhelifa ahmed Derradji Billel Kenchache Youce Mareche Hachemi Department of agronomy science (Animal production) Saad Dhlablab University Blida 09100 Algeria Department of veterinary science Saad Dahlab University Blida 09100 Algeria National Agronomy Institute Algiers 16010 Algeria

The carried out experimental work aimed at the improvement of the native rabbit zootechnical performances. The goal was to run a genetical progress of an exotic breed ＂the Californian＂ through a crossbreeding with a native rabbit. Ten females have been crossed with two native males （L × C） compared to controls Native × Native （N × N） and Californian × Californian （C × C）. The reproduction and growth performances are clearly improved by crossbreeding effect, the recorded heterosis are： 9.43%, 16.34% and 21.93%, respectively for the alive litter size, alive and weaned; 10%, 16.75% and 2.57%, respectively for the alive litter weight, alive and weaned; 2.57% for the individual weight at birth; 10% and 7% for post weaning performances, respectively day mean gains and feed conversion ratio. Weight at slaughter is improved with 167 g, which representing a considerable level for the native population. Genetic crossbreeding between the Algerian native rabbit and the Californian, raised under rearing conditions of the Blida university farm experiment showed its efficiency on the most zootechnical performances. The complementary effect turned up positively on the crossbred rabbits Their post-weaning growth performance is comparable to those of the Californian with a better viability at weaning and slaughtering age.

关键词： Rabbit performance crossbreeding heterosis.

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A Spectrally Selective Window for Hot Climates

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Journal of Electronics Cooling and Thermal Control 2017年第2期7卷 33-44页

作者： M. O. sid-ahmed M. H. Bilal S. G. Babiker Department of Physics Omdurman Ahlia University Omdurman Sudan Department of Physics Faculty of Education University of Algadarif Gadaref Sudan Department of Physics Red Sea University Port Sudan Sudan

Rigorous coupled-wave analysis has been used to design a glazing for hot climates. The designed glazing is relatively simple and it transmits most of the visible light and reflects most of the infrared radiation. It does not need any external source of energy to control its optical properties. It consists of ITO and four periodic pairs of Si/SiO2, deposited on a glass sheet. The optimum thicknesses of ITO, Si and SiO2 are 0.1 μm, 0.15 and 0.4 μm, respectively. The glazing acts as an optically selective filter. It transmits about 80% of the visible light and reflects almost all the infrared radiation. The performance of the glazing is almost independent of the angle of incidence of solar radiation. This makes it suitable for all hours of the day. The fabrication of the glazing and the testing have been performed at the laboratories of the Faculty of Science, University of Witwatersrand, South Africa. Magnetron sputtering technique has been used for the fabrication. ITO, Si and SiO2 have been used as sputtering targets. The experimental results are almost identical to the simulation results.

关键词： Smart Windows Electrochromic Windows Thermochromic Windows Hot Climates

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