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Spatial Variability and Cartography of Maximum Annual Daily Rainfall under Different Return Periods in Northern Algeria

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Journal of Mountain Science 2015年第6期12卷 1403-1421页

作者： MEDDI Mohamed toumi Samir National High School of Hydraulic (ENSH)

The estimation of precipitation quantiles has always been an area of great importance to meteorologists, hydrologists, planners and managers of hydrotechnical infrastructures. In many cases, it is necessary to estimate the values relating to extreme events for the sites where there is little or no measurement, as well as their return periods. A statistical approach is the most used in such cases. It aims to find the probability distribution that best fits the maximum daily rainfall values. In our study, 231 rainfall stations were used to regionalize and find the best distribution for modeling the maximum daily rainfall in Northern Algeria. The L-moments method was used to perform a regionalization based on discordance criteria and homogeneity test. It gave rise to twelve homogeneous regions in terms of LCoefficient of variation(L-CV), L-Skewness(L-CS) and L-Kurtosis(L-CK). This same technique allowed us to select the regional probability distribution for each group using the Z statistic. The generalized extreme values distribution(GEV) was selected to model the maximum daily rainfall of 10 groups located in the north of the steppe region and the generalized logistic distribution(GLO) for groups representing the steppes of Central and Western Algeria. The study of uncertainty by the bias and RMSE showed that the regional approach is acceptable. We have also developed maximum daily rainfall maps for 2, 5, 10, 20, 50 and 100 years return periods. We relied on a network of 255 rainfall stations. The spatial variability of quantiles was evaluated by semi-variograms. All rainfall frequency models have a spatial dependence with an exponential model adjusted to the experimental semi-variograms. The parameters of the fitted semi-variogram for different return periods are similar, throughout, while the nugget is more important for high return periods. Maximum daily rainfall increases from South to North and from West to East, and is more significant in the coastal areas of ea

关键词： Annual maximum daily rainfall Regionalisation L-moments Mapping Northern Algeria

Reduced Sensitivity of Tropical Cyclone Intensity and Size to Sea Surface Temperature in a Radiative-Convective Equilibrium Environment

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Advances in Atmospheric Sciences 2018年第8期35卷 85-97页

作者： Shuai WANG Ralf toumi State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of Oceanography Space and Atmospheric Physics Group Department of PhysicsImperial College London

It has been challenging to project the tropical cyclone （TC） intensity, structure and destructive potential changes in a warming climate. Here, we compare the sensitivities of TC intensity, size and destructive potential to sea surface warming with and without a pre-storm atmospheric adjustment to an idealized state of Radiative-Convective Equilibrium （RCE）. Without RCE, we find large responses of TC intensity, size and destructive potential to sea surface temperature （SST） changes, which is in line with some previous studies. However, in an environment under RCE, the TC size is almost insensitive to SST changes, and the sensitivity of intensity is also much reduced to 3% ~C-1-4% ~C-1. Without the pre-storm RCE adjustment, the mean destructive potential measured by the integrated power dissipation increases by about 25% ~C-1 during the mature stage. However, in an environment under RCE, the sensitivity of destructive potential to sea surface warming does not change significantly. Further analyses show that the reduced response of TC intensity and size to sea surface warming under RCE can be explained by the reduced thermodynamic disequilibrium between the air boundary layer and the sea surface due to the RCE adjustment. When conducting regional-scale sea surface warming experiments for TC case studies, without any RCE adjustment the TC response is likely to be unrealistically exaggerated. The TC intensity-temperature sensitivity under RCE is very similar to those found in coupled climate model simulations. This suggests global mean intensity projections under climate change can be understood in terms of a thermodynamic response to temperature with only a minor contribution from any changes in large-scale dynamics.

关键词： tropical cyclone sea surface temperature radiative-convective equilibrium intensity size destructive potential

SIMPLE PROOFS OF THE CAUCHY-SCHWARTZ INEQUALITY AND THE NEGATIVE DISCRIMINANT PROPERTY IN ARCHIMEDEAN ALMOST f-ALGEBRAS

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Analysis in Theory and Applications 2009年第2期25卷 117-124页

作者： Adel toumi Mohamed Ali toumi Nedra toumi Laboratoire de Physique des Liquides Critiques Département de Physique Faculté des Sciences de Bizerte 7021 Zarzouna Bizerte Tunisia Département des Mathématiques Faculté des Sciences de Bizerte 7021 Zarzouna Bizerte Tunisia

The paper presents simple proofs of the Cauchy-Schwartz inequality and the negative discriminant property in archimedean almost f-algebras^[5], based on a sequence approximation.

关键词： Cauchy-Schwartz inequality f-algebra almost f-algebra positive square g-algebra

Lightning activity on the central Tibetan Plateau and its response to convective available potential energy

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Chinese Science Bulletin 2003年第3期48卷 296-299页

作者： QIEXiushu R.toumi 等 ColdandAridRegionsEnvironmentalandEngineeringResearchInstitute.ChineseAcademyofSciences Lanzhou730000China ColdandAridRegionsEnvironmentalandEngineeringResearchInstitute.ChineseAcademyofSciences Lanz

Lightning flash activities on the central Tibetan Plateau have been studied by using the satellite-based Light-ning Imaging Sensor (LIS) database from January 1998 to July 2002. The lightning activity shows a clear diurnal varia-tion on the central Plateau. The peak lightning activity ap-pears at about 17︰00 which is 3 h earlier than that in Jing-zhou, Hubei in the same latitude belt nearby, indicating that the lightning activity is a sensitive indicator of solar heating on the Plateau. The lightning discharge is weaker on the Plateau than Jingzhou, Hubei and other low-altitude conti-nental regions because of the lower convective available po-tential energy (CAPE) on the Plateau. The CAPE on the Plateau is 12 times lower than that in Jingzhou, Hubei, and 20 times lower than that in the sea-level region, such as Guangzhou and Florida. However, the sensitivity of lightning activity to CAPE changes on the Plateau is up to 30 times more sensitive than other prominent low-altitude regions.

关键词：青藏高原中部闪电活动对流性电势能卫星图片气候资料

Prognostic significance of hepatic encephalopathy in patients with cirrhosis treated with current standards of care

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World Journal of Gastroenterology 2020年第18期26卷 2221-2231页

作者： Anuj Bohra Thomas Worland Samuel Hui ryma Terbah Ann Farrell Marcus Robertson Department of Gastroenterology Monash HealthClayton 3168VictoriaAustralia Department of Gastroenterology Austin HealthHeidelberg 3084VictoriaAustralia Department of Medicine School of Clinical SciencesMonash UniversityClayton 3168VictoriaAustralia

BACKGROUND Hepatic encephalopathy(HE)is a reversible neuropsychiatric complication of liver cirrhosis and occurs in up to 50%of cirrhotic *** examining the prognostic significance of HE are limited despite the high prevalence in *** To define the clinical outcomes of patients after an episode of HE treated with current *** All patients hospitalised with HE requiring Rifaximin to 3 tertiary centres over46-mo(2012–2016)were identified via pharmacy dispensing *** with hepatocellular carcinoma and those prescribed Rifaximin prior to admission were *** records were reviewed to determine baseline characteristics and *** Kaplan-Meier method was used to calculate survival *** survival analysis was performed with variables reaching statistical significance included in a multivariate *** primary outcome was 12-mo mortality following commencement of ***188 patients were *** age was 57 years(IQR 50-65),71%were male and median model for end stage liver disease and Child Pugh scores were 25(IQR 18-31)and 11(IQR 9-12)*** most common causes of cirrhosis were alcohol(62%),hepatitis C(31%)and non-alcoholic fatty liver disease(20%).A precipitating cause for HE was found in 92%patients with infection(43%),GI bleeding(16%),medication non-compliance(15%)and electrolyte imbalance(14%)the most *** a mean follow up period of 12±13 mo 107(57%)patients died and 32(17%)received orthotopic liver *** common causes of death were decompensated chronic liver disease(57%)and sepsis(19%).The probability of survival was 44%and 35%at 12-and 24-mo *** multivariate analysis a model for end stage liver disease>15 and international normalised ratio reached statistical significance in predicting *** Despite advances made in the management of HE patients continue to have poor ***,in all patients

关键词： Hepatic encephalopathy Cirrhosis Portal hypertension Prognosis Rifaximin Lactulose

Existence and Global Asymptotic Behavior of Positive Solutions for Sublinear and Superlinear Fractional Boundary Value Problems

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Chinese Annals of Mathematics,Series B 2016年第1期37卷 1-28页

作者： Imed BACHAR Habib MAAGLI Faten toumi Zagharide ZINE EL ABIDINE Mathematics Department College of Science King Saud University P.O.Box 2455 Riyadh 11451 Saudi Arabia. Department of Mathematics College of Sciences and Arts Rabigh Campus King Abdulaz University P.O.Box 344 Rabigh 21911 Saudi Arabia. Departement de Mathematiques Faculte des Sciences de Tunis Campus Universitalre 2092 Tunis Tunisia.

In this paper, the authors aim at proving two existence results of fractional differential boundary value problems of the form （Pa,bα）{D^au（x）＋f（x,u（x））=0,x∈（0,1）,u（0）=u（1）=0,D^a-3u（0）=a,u^（1）=-6where 3 ≤ a 〈 4, D^ is the standard Riemann-Liouville fractional derivative and a, b are nonnegative constants. First the authors suppose that f（x, t） = -p（x）t^σ, with cr ~ （-1, 1） and p being a nonnegative continuous function that may be singular at x - 0 or x - 1 and satisfies some conditions related to the Karamata regular variation theory. Combining sharp estimates on some potential functions and the Sch^uder fixed point theorem, the authors prove the existence of a unique positive continuous solution to problem （P0,0）. Global estimates on such a solution are also obtained. To state the second existence result, the authors assume that a, b are nonnegative constants such that a ＋ b 〉 0 and f（x, t） -= tφ（x, t）, with φ（x, t） being a nonnegative continuous function in （0, 1） × [0, ∞） that is required to satisfy some suitable integrability condition. Using estimates on the Green＇s function and a perturbation argument, the authors prove the existence and uniqueness of a positive continuous solution u to problem （Pa,b）, which behaves like the unique solution of the homogeneous problem corresponding the existence results. to （Pa,b）. Some examples are given to illustrate the existence results.,

关键词： Fractional differential equation Positive solution Fractional Green's function Karamata function Perturbation arguments Sch/iuder fixad point theorem

Importance of Air-Sea Coupling in Simulating Tropical Cyclone Intensity at Landfall

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Advances in Atmospheric Sciences 2022年第10期39卷 1777-1786页

作者： Charlie C.F.LOK Johnny C.L.CHAN Ralf toumi School of Energy and Environment City University of Hong KongHong KongChina Department of Physics Imperial CollegeLondon SW72AZUK

An atmosphere-only model system for making seasonal prediction and projecting future intensities of landfalling tropical cyclones(TCs)along the South China coast is upgraded by including ocean and wave models.A total of 642 TCs have been re-simulated using the new system to produce a climatology of TC intensity in the South China *** comparisons of the simulations from the atmosphere-only and the fully coupled systems reveal that the inclusion of the additional ocean and wave models enable differential sea surface temperature responses to various TC characteristics such as translational speed and *** particular,interaction with the ocean does not necessarily imply a weakening of the TC,with the coastal bathymetry possibly playing a role in causing a near-shore intensification of the *** results suggest that to simulate the evolution of TC structure more accurately,it is essential to use an air-sea coupled model instead of an atmosphere-only model.

关键词： tropical cyclone intensity tropical cyclone landfall seasonal prediction air-sea coupling

Synergistic combination of colistin with imipenem, amikacineor ciprofloxacin against Acinetobacter baumannii andPseudomonas aeruginosa carbapenem-resistant isolated inAnnaba hospital Algeria

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BIOCELL 2020年第2期44卷 175-182页

作者： SAIDA MELIANI SOUMAYA toumi HEYTHEM DJAHOUDI KHALED DEGHDEGH KAMEL AMOURA ABDELGHANI DJAHOUDI Department of Biochemistry Faculty of SciencesLaboratory of MicrobiologyBadji Mokhtar UniversityAnnabaAlgeria Department of Biochemistry Eco-biology Laboratory for Marine and Coastal AreasFaculty of SciencesBP 12 El-HadjarBadjiMokhtar UniversityAnnabaAlgeria Faculty of Medicine Pulmonology Service Badji Mokhtar UniversityAnnabaAlgeria Faculty of Medicine CHU AnnabaBadji Mokhtar UniversityAnnabaAlgeria Department of Pharmacy Faculty of MedicineLaboratory of MicrobiologyBadji Mokhtar UniversityAnnabaBP 205Algeria

Objective:The aim of this study is to detect in vitro the synergetic activity of colistin in combination with imipenem,amikacin or ciprofloxacin,at sub-inhibitory concentrations,against carbapenems-resistant(CR)Acinetobacter baumannii and Pseudomonas aeruginosa strains isolated from various wards in Annaba teaching hospital in eastern *** and Methods:The minimal inhibitory concentrations(MIC)were determined by broth macrodilution(BMD).Carbapenemase encoding genes were screened using polymerase chain reaction(PCR).The activity of colistin in combination with second antibiotic was evaluated by the Checkerboard ***:39 CR *** and 21 CR *** strains where *** MIC values ranging from(0.25 to 4μg/ml)to colistin,≥16μg/ml for imipenem,≥4μg/ml to amikacin and≥8μg/ml *** PCR reveals the presence of the genes blaOXA23(n=12),blaOXA24(n=6),blaNDM1(n=3)in *** and blaVIM2(n=12)in *** combination of colistin with imipenem showed synergistic effect on 57.14%and 46.15%of *** and *** isolates,*** colistin and amikacin,the synergistic effect is detected in 28.6%of *** and 30.8%of *** colistin and ciprofloxacin showed synergy on 14.29%and 15.38%of *** and *** isolates,***:CR *** and *** remain the most prevalent infection agents in patients from high-risk wards at Annaba *** associated with imipenem or with amikacin at sub-inhibitory concentrations gives very encouraging results allowing better management of infections caused by this type of bacteria.

关键词： Carbapenemases Colistin Combination GNB-NF Sub-inhibitory concentration

Thermoluminescent response of gamma irradiated Na^(+)–Cu^(+) ionexchanged silicate glass in large dose range

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Nuclear Science and Techniques 2023年第5期34卷 22-32页

作者： Safa toumi Khaled Farah Laboratoire de Physico‑Chimie des Matériaux Département de PhysiqueFacultédes Sciences de MonastirUniversitéde MonastirMonastirTunisia Institut Supérieur du Transport et de la Logistique de Sousse Universitéde Sousse4023 SousseTunisia Laboratoire de Recherche en Energie et Matière Développement des Sciences Nucléaires(LR16CNSTN02)Centre National des Sciences et Technologies Nucléaires2020 Sidi‑ThabetTunisia

The introduction of metals into vitreous matrices is the origin of various interesting phenomena;in particular,the presence of copper ions in glass has been the subject of considerable research because of its numerous *** ion-exchange process is primarily used to introduce copper ions into glass *** thermoluminescence(TL)of silicate glass was studied to evaluate its potential as gamma-sensitive material for dosimetric applications;the effect of copper doping on the thermoluminescent sensitivity was investigated using the Cu-Na ion-exchange technique for different concentrations and doping conditions,over a wide dose range of 10 mGy to 100 *** results showed that Cu doping significantly improved the sensitivity of the glasses to gamma *** the ion-exchange,two peaks appeared in the glow curves at approximately 175 and 230°C,respectively,which possibly originated from the Cu^(+) centers,along with a weak TL peak at around 320℃.We also attempted to explain the origin of the observed thermoluminescence by exploiting the Electron paramagnetic resonance(EPR)*** results clearly show quenching of the TL emission with increasing copper *** present work indicates that the thermoluminescence response of these glasses to gamma rays can be reasonably measured in the range of 0.001-100 *** study also facilitates the understanding of the basic TL mechanism in this glass system.

关键词： Cu-Na ion-exchange Silicate glass Thermoluminescence Gamma irradiation Electron paramagnetic resonance