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Interactions of zinc and cadmium toxicity in their effects on growth and in antioxidative systems in tomato plants (Solanum lycopersicum)

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Journal of Environmental Sciences 2011年第5期23卷 837-844页

作者： Jaouhra Cherif Chamseddine Mediouni wided ben ammar Fatma Jemal Unit of Research "Nitrogenized Nutrition and Metabolism and Stress Proteins" UR 99/09-20 Department of BiologyFaculty of Science University of Tunis Tunis 2092 Tunisia Unit of Research "Nitrogenized Nutrition and Metabolism and Stress Proteins" UR 99/09-20 Department of BiologyFaculty of ScienceUniversity of Tunis Tunis 2092 Tunisia

The interaction between zinc and cadmium was investigated in tomato plants （Solanum lycopersicum）. Ten-day-old seedlings were treated with 10 μmol/L CdC12 associated to different concentrations of ZnC12 （10, 50, 100, and 150 μmol/L）. Zn supply clearly reduced Cd accumulation in leaves and simultaneously increased Zn concentration. Cd induced oxidative stress in leaves as indicated by an increase in thiobarbituric acid-reactive substances （TBARS） level and chlorophyll breakdown. Furthermore, compared with control, Cd- treated plants had significantly higher activities of superoxide dismutase （SOD, EC 1.***.1.1）, whereas, catalase （CAT, EC 1.***.1.6）, ascorbate peroxidase （APX, EC 1.***.1.11）, and glutathione reductase （GR, EC 1.***.4.2） activities were significantly suppressed by Cd addition. Zn supplementation, at low level, restored and enhanced the functional activity of these enzymes （SOD, CAT, APX and GR） as compared to Cd-alone-treated plants. The beneficial effect of adequate Zn level on Cd toxicity was confirmed by a significant decrease in TBARS level and restoration of chlorophyll content. However, when Zn was added at high level in combination with Cd there was an accumulation of oxidative stress, which was higher than that for Cd or excess Zn alone treatments. These results suggested that higher Zn concentrations and Cd are synergistic in their effect on plant growth parameters and oxidative stress.

关键词： Solanum lycopersicum cadmium zinc oxidative stress antagonism synergism.

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SIMAD:Secure Intelligent Method for IoT-Fog Environments Attacks Detection

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Computers, Materials & Continua 2022年第2期70卷 2727-2742页

作者： wided ben Daoud Sami Mahfoudhi NTS’Com Research Unit SfaxTunisia Department of MIS CBEQassim UniversityBuraidahAl QassimKSA

The Internet of Thing IoT paradigm has emerged in numerous domains and it has achieved an exponential ***,alongside this advancement,IoT networks are facing an ever-increasing rate of security risks because of the continuous and rapid changes in network *** order to overcome these security challenges,the fog system has delivered a powerful environment that provides additional resources for a more improved data ***,because of the emerging of various breaches,several attacks are ceaselessly emerging in IoT and Fog ***,the new emerging applications in IoT-Fog environment still require novel,distributed,and intelligent security models,controls,and *** addition,the ever-evolving hacking techniques and methods and the expanded risks surfaces have demonstrated the importance of attacks detection *** proves that even advanced solutions face difficulties in discovering and recognizing these small variations of *** fact,to address the above problems,Artificial Intelligence(AI)methods could be applied on the millions of terabytes of collected information to enhance and optimize the processes of IoT and fog *** this respect,this research is designed to adopt a new security scheme supported by an advanced machine learning algorithm to ensure an intelligent distributed attacks detection and a monitoring process that detects malicious attacks and updates threats signature databases in IoTFog *** evaluated the performance of our distributed approach with the application of certain machine *** experiments show that the proposed scheme,applied with the Random Forest(RF)is more efficient and provides better accuracy(99.50%),better scalability,and lower false alert *** this regard,the distribution character of our method brings about faster detection and better learning.

关键词： Attack detection Fog IoT network machine learning distributed mechanism

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Kinetics of the Anti-oxidant Response to Salinity in the Halophyte Cakile maritima

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Journal of Integrative Plant Biology 2007年第7期49卷 982-992页

作者： Nader ben Amor Ana Jimenez wided Megdiche Marianne Lundqvist Francisca Sevilla Chedly Abdelly Centre de Biotechnologie a la Technopole de Borj Cedna Laboratoire d'Adaptation des Plantes sux Stress Abiotiques BP 901 Hammam-Lif 2050 Tunisia Department of Plant Stress Biology and Pathology Centro de Edafologia y Biologia Aplicada del Segura Consejo Superior de Investigaciones Cientificas (CSIC) Apdo. 164 E-30100 Murcia Spain

The effects of NaCl stress on the activity of anti-oxidant enzymes （superoxide dismutase, catalase （CAT）, peroxidase （POD）, ascorbate peroxidase （APX）, monodehydroascorbate reductase, dehydroascorbate reductase （DHAR）, and glutathione reductase （GR））, anti-oxidant molecules （ascorbate and glutathione）, and parameters of oxidative stress （malondialdehyde （MDA）, electrolyte leakage, and H2O2 concentrations） were investigated in Cakile maritima, a halophyte frequent along the Tunisian seashore. Seedlings were grown in the presence of salt （100, 200, and 400 mmol/L NaCl）. Plants were harvested periodically over 20 days. Growth was maximal in the presence of 0-100 mmol/L NaCl. At 400 mmol/L NaCl, growth decreased significantly. The salt tolerance of C. maritima, at moderate salinities, was associated with the lowest values of the parameters indicative of oxidative stress, namely the highest activities of POD, CAT, APX, DHAR, and GR and high tissue content of ascorbate and glutathione. However, prolonged exposure to high salinity resulted in a decrease in anti-oxidant activities and high MDA content, electrolyte leakage, and H2O2 concentrations. These results suggest that anti-oxidant systems participate in the tolerance of C. maritima to moderate salinities.

关键词： anti-oxidant activities ascorbate glutathione halophyte lipid peroxidation salt tolerance.

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Novel Kernel Function With a Hyperbolic Barrier Term to Primal-dual Interior Point Algorithm for SDP Problems

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Acta Mathematicae Applicatae Sinica 2022年第1期38卷 44-67页

作者： Imene TOUIL wided CHIKOUCHE LMPA Mohammed Seddik Ben Yahia UniversityJijel 18000Algeria

In this paper,we introduce for the first time a new eligible kernel function with a hyperbolic barrier term for semidefinite programming(SDP).This add a new type of functions to the class of eligible kernel *** prove that the interior-point algorithm based on the new kernel function meets O(n3/4 logε/n)iterations as the worst case complexity bound for the large-update *** coincides with the complexity bound obtained by the first kernel function with a trigonometric barrier term proposed by El Ghami et ***2012,and improves with a factor n(1/4)the obtained iteration bound based on the classic kernel *** present some numerical simulations which show the effectiveness of the algorithm developed in this paper.

关键词： Linear Semidefinite Programming Primal-Dual Interior Point Methods Hyperbolic Kernel Function Complexity Analysis Large and small-update methods

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Epidemiology of Occupational Asthma in Tunisia: Results of a First National Study

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Occupational Diseases and Environmental Medicine 2016年第2期4卷 27-36页

作者： Maoua Maher El Maalel Olfa Boughattas wided Chatti Souhail Gharbi Ezzeddine Kammoun Houda Kalboussi Houda Mlaouah Jabrane Abbassi ammar Brahem Aicha Loukil Mouna Haj Salah Habib ben Khdimallah Khaled Masmoudi Tasnim benzarti Mohamed Debbabi Faten Mrizak Néjib Occupational Medicine and Professional Pathologies Department Faculty of Medicine of Sousse Sousse Tunisia University of Sousse Sousse Tunisia CNAM Regional Centers of Sousse Tunis and Sfax Tunisia English Department Faculty of Medicine of Sousse Sousse Tunisia Forensic Medicine Department Faculty of Medicine of Sousse Sousse Tunisia Department of Pneumology and Allergology Farhat Hached Teaching Hospital Sousse Tunisia

Introduction: Apart from its increasingly important frequency, occupational asthma (OA) has become the most important cause of occupational respiratory disorders in developed countries. The number of etiological agents continues to grow following the constant introduction of new harmful substances in industry. Objectives: Determine the prevalence and incidence of OA in our country, the socio-occupational characteristics of asthmatics, and study the forensic and social impact of such pathology. Material and Methods: An exhaustive retrospective epidemiological study was conducted in Tunisia about charts of occupational asthma cases recognized by the competent commissions of the National Medical Care Fund (CNAM) during the period ranging from January 1st 2000 to December 31st 2008. Results: 361 occupational asthma cases, accounting for a prevalence of 7.17% of all occupational diseases, were recognized during the period of the study. Occupational asthma annual incidence was estimated to be 24.42 cases per 1000000 workers. Our study population was mainly women with a sex ratio of 0.86. More than a half (57.6%) of recognized OA cases were working in the textile industry sector. Concerning the asthmatics’ professional career, most of recognized OA cases (n = 225 i.e. 70.6% of cases) kept their jobs, whereas 58 patients did not. The professional career was linked to gender with a job loss that is 1.79 time more important in asthmatic women. Conclusion: The incidence of occupational asthma in Tunisia is comparable with that found in other Mediterranean countries. A rigorous and adequate prevention is necessary and allows reducing the importance of this occupational pathology and its serious consequences.

关键词： Epidemiology Occupational Asthma Pneumology Allergology Tunisia

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Hospital Night Shift and Its Effects on the Quality of Sleep, the Quality of Life, and Vigilance Troubles among Nurses

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International Journal of Clinical Medicine 2014年第10期5卷 572-583页

作者： wided Boughattas Olfa El Maalel Ridha ben Chikh Maher Maoua Kalboussi Houda Aicha Braham Houssem Rhif Souheil Chatti Faten Debbabi Mohamed Dogui Nejib Mrizak Neurophysiology Department Sahloul Teaching Hospital Sousse Tunisia Occupational Medicine and Professional Pathologies Department Medicine Faculty of Sousse Sousse Tunisia

Introduction: The exposure to shift works, and especially to night shift, goes against the circadian rythmicity of the social man, which brings about a multitude of disruptive effects on health. In a hospital environment, such night shift is necessary so as to ensure the continuity of care. Sleep and vigilance disorders related to this work mode are frequent and often pose adaptation problems. The objective of this study is to detect the harmful effects of night shift on sleep, vigilance and the quality of life of nurses in Farhat Hached Teaching Hospital in Sousse. Material and Methods: It is a cross-sectional study carried out among two groups of nurses: one group performing a fixed night work and the other one working permanently during the day at Farhat Hached Teaching Hospital in Sousse. Data collection is mainly based on validated questionnaires evaluating sleep quality (Pittsburg sleep quality index), daytime sleepiness (Epworth sleepiness scale), sleep typology (Horne and Ostberg questionnaire), and the quality of life (SF-12). An objective evaluation of vigilance was realized by the study of reaction time and error rates to different tasks of “Super lab” software. Results: 50 night and 50 day nurses have been colligated. Both groups were age- and gender-matched. Sleep quality mean index was significantly higher among night nurses in comparison with day nurses (10.2 ± 5.9 versus 6.76 ± 5.16). After multivariate analysis, sleep quality was significantly correlated to age, department, schedule and the choice of schedule. Night shift was not related to daytime sleepiness. The objective analysis of vigilance showed that the reaction time to different tasks exploring the attentional mechanisms, as well as errors rate, were significantly more important among the night group. The mental score of the quality of life was significantly higher among day nurses. However, such difference was not significant with regard to physical score. Conclusion: The findings of our s

关键词： Night Shift Nurse Quality of Life Sleep Vigilance

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