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Seasonal variability in CdOM absorption and fluorescence properties in the Barataria Basin,Louisiana,Usa

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Journal of Environmental Sciences 2010年第10期22卷 1481-1490页

作者： Shatrughan Singh Eurico d'sa Erick Swenson department of Oceanography and Coastal Sciences Louisiana State University

Absorption and fluorescence properties of chromophoric dissolved organic matter （CdOM） along a 124 km transect in the Barataria Basin, a large estuary located in Louisiana, Usa, were investigated during high and low flow periods of the Mississippi River in the spring and winter of 2008-2009. Mean CdOM absorption at 355 nm from the marine to the freshwater end member stations ranged from （3.25 ± 0.56） to （20.76 ± 2.43） m^-1 for the three month high flow period whereas it varied from （1.48 ± 1.08） to （25.45 ± 7.03） m^-1 for the same stations during low flow period. Corresponding salinity values at these stations indicated the influence of river and shelf exchanges in the lower basin and precipitation and runoff in the upper basin. An inverse relationship of CdOM absorbance and fluorescence with salinity observed in the basin could he a useful indicator of salinity. CdOM fluorescence also varied over a large range showing an approximately 8 to 12-fold increase between the marine and freshwater end members for the two flow seasons. Excitation-emission matrix spectral plots indicated the presence of various fluorescence components with highest being the A-peak, lowest the T-peak, and the C and M-peaks showing similar trends along the transect. during low flow season the A/C ratio were well correlated with station locations indicating increased terrestrial influence towards the upper basin. CdOM absorption and fluorescence at 355 nm were highly correlated and independent of CdOM sources suggesting that fluorescence could be used to characterize CdOM in the basin.

关键词： Barataria Basin chromophoric dissolved organic matter CdOM fluorescence excitation-emission matrix

Analysis and optimal synthesis of single loop spatial mechanisms

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第9期12卷 665-679页

作者： Med Amine LARIBI Lotfi ROMdHANE sa.d ZEGHLOUL Laboratoire de Génie Mécanique LAB-MA-05 Ecole Nationale d'Ingénieurs de Sousse Institut Pprime-UPR 3346 CNRS-Université de Poitiers-ENSMA Département Génie Mécanique et Systémes Complexes SP2MIBP30179 86962 Futuroscope France

In this work, a systematic approach is presented to obtain the input-output equations of a single loop 4-bar spatial mechanisms. The dialytic method along with denavit-Hartenberg parameters can be used to obtain these equations efficiently. A genetic algorithm （GA） has been used to solve the problem of spatial mechanisms synthesis. Two types of mechanisms, e.g., RSCR and RSPC （R： revolute; S： spherical; C： cylindrical; P： prismatic）, have illustrated the application of the GA to solve the problem of function generation and path generation. In some cases, the GA method becomes trapped in a local minimum. A combined GA-fuzzy logic （GA-FL） method is then used to improve the final result. The results show that GAs, combined with an adequate description of the mechanism, are well suited for spatial mechanism synthesis problems and have neither difficulties inherent to the choice of the initial feasible guess, nor a problem of convergence, as it is the case for deterministic methods.

关键词： Spatial mechanisms Genetic algorithm-fuzzy logic (GA-FL) method denevit-Hartenberg parameters Mechanism synthesis

Modeling the Spatio-Temporal dynamics of Local Context for a Contextualized diffusion of Agroecological Intensification Options in Niger

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International Journal of Geosciences 2024年第3期15卷 270-301页

作者： Nouhou salifou jangorzo Maud Loireau Abou-Souﬁanou sa.da Ousmane sami Mari Abdoul-Aziz sa.dou Hassane Bil-Assanou Issoufou département des Sciences du Sol et Télédétection Université Dan Dicko Dankoulodo de Maradi UMR DAP Maradi Niger Unité mixte de Recherche diversité et Adaptation des Plantes (UMR dAP) Université Dan Dicko Dankoulodo de Maradi Maradi Niger Institut de Recherche pour le développement UMR Espace-DEV Université de Perpignan Via Domitia (UPVD) Perpignan France Institut de Recherche pour le développement Représentation Niamey Niger Centre Imaan de Support en Recherche Transdisciplinaire UMR DAP/UDDM Niamey Niger département des Sciences et Techniques de Productions Végétales Université Dan Dicko Dankoulodo de Maradi UMR DAP Maradi Niger

Spatio-temporal variability and dynamics in sahelian agro-pastoral zones make each local situation a special case. These specificities must be considered to guide the dissemination of agricultural options with a view to sustainable development. The territorial scale of municipalities is not sufficient for this necessary contextualization;the scale of the “village terroir” seems to be a better option. This is the hypothesis we put forward in the framework of the Global Collaboration for Resilient Food Systems program (CRFS), i.e. local context is spatially defined by village terroir. The study is based on data collected through participatory mapping and surveys in “village terroirs” in three regions of Niger (Maradi, dosso and Tillabéri). Then the links between farm managers and their cultivated land, as well as the spatio-temporal dynamics of local context are analyzed. This study provides evidence of the existence and functional usefulness of the village terroir for farmers, their land management and their activities. It demonstrates the usefulness of contextualizing agricultural options at this scale. Their analysis elucidates the links between “terroirs village” and the specific functioning of the agrosocio-ecosystems acting on each of them, thus laying the systemic and geographical foundations for a model of the spatio- temporal dynamics of “village terroirs”. This initial work has opened up new perspectives in modeling and sustainable development.

关键词： Niger Option by Context Local Condition Complex System Multiscale Conceptual Modeling

Hepatocellular carcinoma-the role of the underlying liver disease in clinical practice

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World Journal of Gastroenterology 2024年第19期30卷 2488-2495页

作者： Angelo Zambam de Mattos Isadora Zanotelli Bombassaro Arndt Vogel Jose d debes department of Internal Medicine Universidade Federal de Ciências da Saúde de Porto AlegreRSPorto Alegre 90020090Brazil Graduate Program in Medicine:Hepatology Federal University of Health Sciences of Porto AlegreRSPorto Alegre 90050-170Brazil division of Gastroenterology Hepatology University of TorontoHannover M5R 0A3Canada department of Medicine University of MinnesotaMinneapolisMN 55455United States

Hepatocellular carcinoma(HCC)is one of the most common causes of cancerrelated *** particular type of cancer has the distinctive characteristic of mostly happening in individuals with an underlying liver *** makes the management of patients more challenging,since physicians must take into consideration two different conditions,the chronic liver disease and the *** underlying liver disease has several implications in clinical practice,because different kinds of chronic liver disease can lead to varying degrees of risk of developing HCC,obstacles in surveillance,and differences in the efficacy of the treatment against HCC.A shift in the prevalence of liver diseases has been evident over the last few years,with viral hepatitis gradually losing the leading position as cause of HCC and metabolic dysfunction-associated steatotic liver disease gaining ***,in an era of personalized medicine,it is imperative that physicians are aware of the underlying liver disease of individuals with HCC and its impact in the management of their tumors.

关键词： Hepatocellular carcinoma Etiology Epidemiology Surveillance Therapy

A predictive controller for induction motors using an unknown input observer for online rotor resistance estimation and an update technique for load torque

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控制理论与应用（英文版） 2013年第3期11卷 367-375页

作者： Hanen CHEHIMI salim HAdJ sa.d Faouzi MsaHLI department of Electrical Engineering National Engineering School of Monastir

This paper deals with the design of an output feedback predictive controller for induction motors. The fundamental interest of the proposed controller is the capability of decoupling the mechanical speed and the rotor fluxes, without degradation against the variation of rotor resistance and load torque. Hence, the contribution is to apply two estimation procedures in order to achieve this goal. Namely, an unknown input observer （UIO） is used for the constant time estimation whereas a heuristic solution is exploited for the load torque update. Moreover, rotor flux components are recovered as an unavailable state of the system. Effectiveness of the proposed observers and the performance of the controller are confirmed by simulation results.

关键词： Predictive controlle UIO Induction motors Parameters estimation

On the Rayleigh-Plateau instability

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Applied Mathematics(A Journal of Chinese Universities) 2012年第2期27卷 127-138页

作者： Ali AL Riyabi Mohammed Boutat sa.d Hilout Laboratoire de Mathématiques Université de PoitiersBoulevard Marie et Pierre CurieTéléport 2BP 3017986962 Futuroscope Chasseneuil cedexFrance

In this paper,we study the surface instability of a cylindrical pore in the absence of *** instability is called the Rayleigh-Plateau *** consider the model developed by Spencer et al.[18],Kirill et al.[10]and Boutat et al.[2]in the case without *** obtain a nonlinear parabolic PdE of order *** show the local existence and uniqueness of the solution of this problem by using Faedo-Galerkin *** main results are the global existence of the solution and the convergence to the mean value of the initial data for long *** tests are also presented in this study.

关键词： parabolic nonlinear partial differential equation initial boundary value problem local solution uniqueness stability.

A Lightweight Blockchain for IoT in Smart City (IoT-SmartChain)

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Computers, Materials & Continua 2021年第11期69卷 2687-2703页

作者： Zakariae dlimi Abdellah Ezzati sa.d Ben Alla Hassan First University of Settat FacultéSciences et TechniqueLAVETESettat26000Morocco

The smart city is a technological framework that connects the city’s different components to create new *** connection is possible with the help of the Internet of Things(IoT),which provides a digital personality to physical *** studies have proposed integrating Blockchain technology with IoT in different use cases as access,orchestration,or replicated storage *** majority of connected objects’capacity limitation makes the use of Blockchain inadequate due to its redundancy and its conventional processing-intensive consensus like *** paper addresses these challenges by proposing a NOVEL model of a lightweight Blockchain framework(IoT-SmartChain),with a lightweight consensus and a lightweight *** framework architecture presents a role hierarchy of connected objects according to their computational and storage *** organization allows all things to be linked even indirectly via different interfaces and to benefit from the power of high-capacity objects such as Fog and Edge computing *** is validated and added to the blockchain ledger by running a lightweight consensus called Proof of Random Participation(PoRP),which reduces the blockchain nodes’high computing power *** TOPIC subscription-based data storage strategy called Assisted Selected Relevant data in Local Ledger(ASRdLL)reduces the data size of a node’s local ledger and the entire network’s data *** strategy is assisted by a centralized algorithm that optimizes the overall network size by adjusting the choice of *** storage capacity,computational power,and energy consumption have been evaluated by a proof of concept implementation under NodeJS.

关键词： Smart city Internet of Things blockchain lightweight consensus lightweight ledger Iot-SmartChain

On Newton’s Method for Solving Nonlinear Equations and Function Splitting

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Numerical Mathematics(Theory,Methods and Applications) 2011年第1期4卷 53-67页

作者： Ioannis K.Argyros sa.d Hilout Cameron University Department of Mathematics SciencesLawtonOK 73505USA Universitéde Poitiers Laboratoire de Mathématiques et ApplicationsBd.Pierre et Marie CurieTéléport 2B.P.3017986962 Futuroscope Chasseneuil CedexFrance

We provided in[14]and[15]a semilocal convergence analysis for Newton’s method on a Banach space setting,by splitting the given *** this study,we improve the error bounds,order of convergence,and simplify the sufficie... 详细信息

关键词： Newton’s method Banach space majorizing sequence semilocal convergence splitting of an operator

Cadmium bioaccumulation in three benthic fish species, salaria basilisca, Zosterisessor ophiocephalus and Solea vulgaris collected from the Gulf of Gabes in Tunisia

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Journal of Environmental Sciences 2009年第7期21卷 980-984页

作者： BARHOUMI sana MESsaOUdI Imed dELI Tmim sa.d Khaled KERKENI Abdelhamid Trace Elements Free Radicals Antioxidant Systems and Environment and Humain Pathology Faculty of Medicine 5000 Monastir Tunisia UR 09/30: Genetic and Biodiversity Institute of Biotechnology 5000 Monastir Tunisia

To select a marine teleost fish which can be used as a bioindicator of cadmium （Cd） pollution in the Gulf of Gabes in Tunisia, Cd concentrations in liver and gill were compared in three benthic fish species including salaria basilisca, Zosterisessor ophiocephalus and Solea vulgaris. Fish samples were collected from three selected sites in the Gulf of Gabes, with different degrees of Cd contamination： the industrialized coast of Sfax （S 1）, the coast of douar Chatt （S2） and the coast of Luza （S3）. The results shows that Cd concentrations in both sediment and water collected from S1 were significantly higher （t9 〈 0.0001） than those from S2 and S3. For each species, Cd concentrations, in both liver and gill, showed the decreasing order： S 1 〉 S2 〉 S3. The highest concentration of Cd was detected in the liver of S. basilisca, and only S. basilisca showed bioaccumulation factors （BAF） greater than 1 in all studied sites. In S 1 and S2, BAF values respect the following order： S. basilisca 〉 Z. ophiocephalus 〉 S. vulgaris. These results of significant bioaccumulation of Cd, in terms of hepatic concentrations and bioaccumulation factors, indicated that S. basilisca can be used as bioindicator to evaluate the evolution of Cd pollution in the Gulf of Gabes.

关键词： bioaccumulation cadmium Gulf of Gabes salaria basilisca Solea vulgaris Zosterisessor ophiocephalus Tunisia