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Particuology 2015年第1期13卷 179-185页

作者： Xavier Simon Sébastien Bau denis Bémer Philippe Duquenne institut national de Recherche et de Securite(INRS)

Widely used bioaerosol generators like Collison nebulizer probably produce electrostatically charged par- ticles, but the electrical charges carried by laboratory-generated airborne microorganisms using bubbling aerosolizers are poorly understood. In this study, we measured the fraction of neutral particles and num- ber of elementary charges per particle as a function of the aerodynamic diameter of airborne bacteria （Escherichia coli and Enterococcus hirae）. Bioaerosols were produced by a liquid sparging aerosolizer-type bubbling generator, with particle sizes ranging from roughly 0.6 to 2 p^m. The experimental setup included an electrostatic precipitator and real-time devices including an electrometer, aerodynamic particle sizer, and electrical low-pressure impactor. Experimental results obtained for various operating conditions showed that aerosols produced with a higher bubbling airflow contained a larger proportion of neutral particles （from around 30% to 50%） and that bacteria carried a greater average absolute number of elementary charges （from around -10 to -60 elementary units） than those under lower airflow. Under the investigated conditions, a neutralization step is unnecessary because it may have a negative effect on the viability of sensitive microorganisms. Our results suggest that the neutral fraction can be used down- stream of an electrostatic precipitator, and that this setup may have advantages over bipolar neutralizers.

关键词： Bubbling generator Bioaerosol Electrical charge Electrostatic precipitator Escherichia coil Enterococcus hirae

Serrated Flow Model for Metallic Glasses under Compressive Loading

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Acta Metallurgica Sinica(English Letters) 2013年第5期26卷 503-508页

作者： M.A.Yousfi K.Hajlaoui Z.Tourki A.R.Yavari Laboratoire de Mcanique de Sousse LMS ENISo Universit de Sousse SIMaP-LTPCM Institut National Polytechnique de Grenoble

A rheological model is proposed that incorporates the serrated flow nature of metallic glasses. It involves the process of the nucleation, propagation and the arrest of a shear bands in the samples subjected to compressive deformation at room temperature. Numerical resolution of the constitutive equations resulting from the model is compared with the stress-strain curve obtained from in-situ nano-compression test in SEM of Zrbased metallic glass. Parametric identification method was applied and enabled us to release the physical parameters of the model. The obtained results showed that the model is adequately valid to describe the experimental data and the almost adjustable model parameters are physically meaningful and comparable to literature.

关键词： Metallic glasses Shear bands Serrated flow Rheological modelling Nanocrystallization

Dimensions of hepatocellular carcinoma phenotypic diversity

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World Journal of Gastroenterology 2018年第40期24卷 4536-4547页

作者： Romain Désert Natalia Nieto Orlando Musso institut NuMeCan Université de Rennes 1 Institut national de la recherche agronomique (INRA) Institut national de la santé et de la recherche médicale (INSERM) department of Pathology Department of Medicine (Gastroenterology and Hepatology) University of Illinois at Chicago

Hepatocellular carcinoma(HCC) is the 3^(rd) leading cause of cancer-related death worldwide. More than 80% of HCCs arise within chronic liver disease resulting from viral hepatitis, alcohol, hemochromatosis, obesity and metabolic syndrome or genotoxins. Projections based on Western lifestyle and its metabolic consequences anticipate a further increase in incidence, despite recent breakthroughs in the management of viral hepatitis. HCCs display high heterogeneity of molecular phenotypes, which challenges clinical management. However, emerging molecular classifications of HCCs have not yet formed a unified corpus translatable to the clinical practice. Thus, patient management is currently based upon tumor number, size, vascular invasion, performance status and functional liver reserve. Nonetheless, an impressive body of molecular evidence emerged within the last 20 years and is becoming increasingly available to medical practitioners and researchers in the form of repositories. Therefore, the aim this work is to review molecular data underlying HCC classifications and to organize this corpus into the major dimensions explaining HCC phenotypic diversity. Major efforts have been recently made worldwide toward a unifying "clinically-friendly" molecular landscape. As a result, a consensus emerges on three major dimensions explaining the HCC heterogeneity. In the first dimension, tumor cell proliferation and differentiation enabled allocation of HCCs to two major classes presenting profoundly different clinical aggressiveness. In the second dimension, HCC microenvironment and tumor immunity underlie recent therapeutic breakthroughs prolonging patients' survival. In the third dimension,metabolic reprogramming, with the recent emergence of subclass-specific metabolic profiles, may lead to adaptive and combined therapeutic approaches. Therefore, here we review recent molecular evidence, their impact on tumor histopathological features and clinical behavior and highlight the r

关键词： Liver metabolism Liver zonation Hepatocellular carcinoma classification Wnt/β-catenin TP53 Tumor microenvironment Inflammation Tumor immunity Hepatocyte proliferation Hepatocyte differentiation

Virtual brain twins: from basic neuroscience to clinical use

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national Science Review 2024年第5期11卷 72-86页

作者： Huifang E.Wang Paul Triebkorn Martin Breyton Borana Dollomaja Jean-Didier Lemarechal Spase Petkoski Pierpaolo Sorrentino Damien depannemaecker Meysam Hashemi Viktor K.Jirsa Aix Marseille Université Institut National de la Santéet de la Recherche Médicale Institut de Neurosciences des Systèmes(INS) UMR1106 Service de Pharmacologie Clinique et Pharmacosurveillance AP–HM

Virtual brain twins are personalized, generative and adaptive brain models based on data from an individual's brain for scientific and clinical use. After a description of the key elements of virtual brain twins,we present the standard model for personalized whole-brain network models. The personalization is accomplished using a subject's brain imaging data by three means:(1) assemble cortical and subcortical areas in the subject-specific brain space;(2) directly map connectivity into the brain models, which can be generalized to other parameters; and(3) estimate relevant parameters through model inversion, typically using probabilistic machine learning. We present the use of personalized whole-brain network models in healthy ageing and five clinical diseases: epilepsy, Alzheimer's disease, multiple sclerosis, Parkinson's disease and psychiatric disorders. Specifically, we introduce spatial masks for relevant parameters and demonstrate their use based on the physiological and pathophysiological hypotheses. Finally, we pinpoint the key challenges and future directions.

关键词： virtual brain twin personalized modeling inference neuroscience brain disorder

c-Fos overexpression increases the proliferation of human hepatocytes by stabilizing nuclear Cyclin D1

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World Journal of Gastroenterology 2008年第41期14卷 6339-6346页

作者： Meryem Güller Kahina Toualbi-Abed Agnès Legrand Laurence Michel Alain Mauviel Dominique Bernuau Fanny Daniel institut national de laSanté et de la Recherche Médicale U697 Hpital Saint-Louis institut national de la Santé et de la RechercheMédicale U591 Faculté de Médecine Necker institut national de la Santé et de la RechercheMédicale U773 Centre de Recherche Bichat Beaujon CRB3and Université Paris 7 Denis Diderot site Bichat

AIM： To investigate the effect of stable c-Fos over- expression on immortalized human hepatocyte （IHH） proliferation. METHODS： IHHs stably transfected with c-Fos （IHH- Fos） or an empty vector （IHH-C） were grown in me- dium supplemented with 1% serum or stimulated with 10% serum. Cell proliferation was assessed by cell counts, 3H-thymidine uptake and flow cytometry analyses. The levels of cell cycle regulatory proteins （Cyclin DI, E, A） cyclin dependent kinases （cdk） cdk2, cdk4, cdk6, and their inhibitors p15, p16, p21, p27, total and phosphorylated GSK-3β and epidermal growth factor receptor （EGF-R） were assayed by Western blotting. Analysis of O/c/in D1 mRNA levels was performed by reverse transcription-polymerase chain reaction and real-time polymerase chain reaction （PCR） analysis. Stability of Cyclin DI was studied by cycloheximide blockade experiments. RESULTS： Stable c-Fos overexpression increased cell proliferation under low serum conditions and resulted in a two-fold increase in [3H]-thymidine incorpora- tion following serum addition. Cell cycle analysis by flow cytometry showed that c-Fos accelerated the cell cycle kinetics. Following serum stimulation, Cyclin D1 was more abundantly expressed in c-Fos overexpress- ing cells. Cyclin D1 accumulation did not result from increased transcriptional activation, but from nuclear stabilization. Overexpression of c-Fos correlated with higher nuclear levels of inactive phosphorylated GSK- 3β, a kinase involved in Cyclin D1 degradation and higher levels of EGF-R mRNA, and EGF-R protein com- pared to IHH-C both in serum starved, and in serum stimulated cells. Abrogation of EGF-R signalling in IHH- Fos by treatment with AG1478, a specific EGF-R tyro- sine kinase inhibitor, prevented the phosphorylation of GSK-3β induced by serum stimulation and decreased Cyclin D1 stability in the nucleus. CONCLUSION： Our results clearly indicate a positive role for c-Fos in cell cycle regulation in hepatocytes. Importantly, we delineate

关键词： c-Fos Cyclin DI GSK-3 Cell growth, Cell cycle Hepatoma Epidermal growth factor

Mg(OH)_2 Nanorods Synthesized by A Facile Hydrothermal Method in the Presence of CTAB

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Nano-Micro Letters 2011年第3期3卷 153-159页

作者： Hassouna Dhaouadi Hedia Chaabane Fathi Touati "Laboratoire des Matriaux Utiles" institut national de Recherche et d’Analyse Physico-chimique Ple technologique de Sidi-Thabet "Laboratoire de Microbiologie" institut national de Recherche et d’Analyse Physico-chimique Ple technologique de Sidi-Thabet

Magnesium hydroxide(Mg(OH)_2) nanorods were synthesized by a simple and facile hydrothermal method in the presence of cetyltetramethylammonium bromide(CTAB) as a surfactant. Nanorods of magnesium oxide Mg O were also induced by thermal decomposition of Mg(OH)_2 nanorods at 700. By using disk diffusion technique, the Mg(OH)_2 nanorods were found to exhibit higher antibacterial efficiency against several tested bacterial strains.

关键词： Nanorods Morphology Hydrothermal synthesis

Very high conservation between Cyp6a2 from Drosophila melanogaster and its ortholog Cyp6a26 from D. simulans

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Insect Science 2007年第1期14卷 15-27页

作者： SOPHIE TARES LAURY ARTHAUD ALEXANDRA BRUN-BARALE DIDIER CROCHARD JEAN-MARC BRIde MARCEL AMICHOT institut national de la Recherche Agronomique UMR ROSE 1112 Sophia-Antipolis France

Although Drosophila simulans is closely related to D. melanogaster, very few cytochrome P450 genes have been studied in this species until now. As Cyp6a2 from D. melanogaster is a major gene implicated in the detoxification of xenobiotic molecules, we decided to look for its ortholog in D. simulans. The isolated gene, Cyp6a26, presents structural characteristics very similar to those of Cyp6a2： an identical size of 1590-bp comprising two exons separated by a 69-bp intron and a nucleotide sequence homology of 95%. Many putative transcriptionally important motifs were identified in the upstream DNAs of the two genes but only 16 elements are in common positions. Treatment of flies with phenobarbital leads to an increased production of Cyp6a26 mRNAs. The expression of Cyp6a26 mRNAs varies following developmental stages in the same manner as Cyp6a2. Immunohistochemistry experiments of phenobarbital-treated adult drosophila show that the spatial expression pattern of the two proteins is also conserved between the two species. All these data argue in favor of the conservation of the function of these homologous genes between the two Drosophila species.

关键词： cytochrome P450 Drosophila ortholog mRNA expression promotor

Phenological stage effect on phenolic composition and repellent potential of Mentha pulegium against Tribolium castaneum and Lasioderma serricorne

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Asian Pacific Journal of Tropical Biomedicine 2018年第4期8卷 207-216页

作者： Nidhal Salem Jazia Sriti Olfa Bachrouch Kamel Msaada Saber Khammassi Majdi Hammami Saoussen Selmi Emna Boushih Marwa Ouertani Nesrine Hachani Manef Abderraba Brahim Marzouk Ferid Limam Jouda Mediouni Ben Jemaa Laboratoire des Substances Bioactives Centre de Biotechnologie a la Technopole de Borj Cedria Laboratoire de Protection des Vegetaux Institut National de la Recherche Agronomique de Tunisie (INRAT) institut Superieur des Sciences Biologiques Appliquees de Tunisia Laboratoire de Biotechnologie Appliquee a l'Agriculture Institut National de la Recherche Agronomique de Tunisie (INRAT)

Objective:To elucidate for the first time the phenological stage effect on polyphenol,flavonoid and proanthocyanidin contents of pennyroyal(Mentha pulegium)as well as their antioxidant capacities and insecticidal potentials against Tribolium castaneum and Lasioderma ***:Crude methanol extracts from pennyroyal(Mentha pulegium)aerial parts were evaluated for their anti radical,reducing power activities and repellent potentials against selected coleopteran insects during different phenological ***:Phenolic contents of pennyroyal aerial parts and their antioxidant effects were significantly dependent on maturity stage of the *** maximum of phenol production was reached during the full flowering *** was the major phenol in Mentha pulegium with an amount of6.01 mg/g of dry vegetable matter during this ***,at fructification stage,the highest antioxidant activity was not related to high phenolic *** repulsive effect of pennyroyal extract showed that Lasioderma serricorne was more susceptible to pennyroyal extract than Tribolium castarneum with corresponding median repellent dose values of 0.124and 0.006 mg/mL ***,great differences in insect repulsion depending on extract concentrations,exposure time and developmental stage was *** the lowest concentration(0.125 mg/mL),the repellent effect against Tribolium reached its maximum(90%)during the fructification stage(after 24 h of exposure)while this repellent effect was 80%during the vegetative ***:Due to the strong insecticidal potential of pennyroyal extracts,this study highlights the therapeutic properties of this plant and encourages its use as a safer,environmental-friendly and efficient insecticide in food industry.

关键词： Apigenin Lasioderma Repellent activity Full flowering stage

Locally Enhanced Flow and Electric Fields Through a Tip Effect for Efficient Flow‑Electrode Capacitive deionization

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Nano-Micro Letters 2025年第2期17卷 1-17页

作者： Ziquan Wang Xiangfeng Chen Yuan Zhang Jie Ma Zhiqun Lin Amor Abdelkader Maria‑Magdalena Titirici Libo deng College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060People’s Republic of China Research Center for Environmental Functional Materials College of Environmental Science and EngineeringTongji University1239 Siping RoadShanghai 200092People’s Republic of China department of Chemical and Biomolecular Engineering National University of SingaporeSingapore 117585Singapore department of Engineering Faculty of Science and TechnologyBournemouth UniversityTalbot CampusFern BarrowPooleEngland BH125BBUK institut de Chimie de Nice UniversitéCôte d’AzurUMR CNRS 727228 Av.Valrose06108 NiceFrance department of Chemical Engineering Imperial College LondonSouth Kensington CampusExhibition RdLondon SW72AZUK

Low-electrode capacitive deionization(FCDI)is an emerging desalination technology with great potential for removal and/or recycling ions from a range of ***,it still suffers from inefficient charge transfer and ion transport kinetics due to weak turbulence and low electric intensity in flow electrodes,both restricted by the current ***,a new tip-array current collector(designated as T-CC)was developed to replace the conventional planar current collectors,which intensifies both the charge transfer and ion transport *** effects of tip arrays on flow and electric fields were studied by both computational simulations and electrochemical impedance spectroscopy,which revealed the reduction of ion transport barrier,charge transport barrier and internal *** the voltage increased from 1.0 to 1.5 and 2.0 V,the T-CC-based FCDI system(T-FCDI)exhibited average salt removal rates(ASRR)of 0.18,0.50,and 0.89μmol cm^(-2) min^(-1),respectively,which are 1.82,2.65,and 2.48 folds higher than that of the conventional serpentine current collectors,and 1.48,1.67,and 1.49 folds higher than that of the planar current ***,with the solid content in flow electrodes increased from 1 to 5 wt%,the ASRR for T-FCDI increased from 0.29 to 0.50μmol cm^(-2) min^(-1),which are 1.70 and 1.67 folds higher than that of the planar current ***,a salt removal efficiency of 99.89%was achieved with T-FCDI and the charge efficiency remained above 95%after 24 h of operation,thus showing its superior long-term stability.

关键词： Flow-electrode Capacitive deionization Current collector Tip effect desalination

Carbon–Iron Microfibrous Material Produced by Thermal Treatment of Self-rolled Poly(4-vinyl pyridine) Films Loaded by Fe_2O_3 Particles

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Journal of Materials Science & Technology 2015年第9期31卷 881-887页

作者： Camelia Matei Ghimbeu Aleksandr I.Egunov Andrey S.Ryzhikov Valeriy A.Luchnikov institut de Science des Matériaux de Mulhouse

Ensembles of freeze-dried self-rolled polymer micro-scrolls are explored as template media for produc- ing carbon-iron based composites with fibrous morphology. Polymer fibres impregnated with furfuryl alcohol and loaded with Fe2O3 particles, were thermally treated under inert atmosphere at 700 ℃ and subsequently analysed by scanning and transmission electron microscopy, X-ray diffraction, thermogravimetric analysis, and nitrogen adsorption. The resulting material has a micro-fibrous mor- phology and is basically composed of metallic Fe^0 and FeO particles, i.e., more than 98 wt% of the carbon/ iron-based composite mass. These particles are held together by amorphous porous carbon foam obtained by in-situ carbonization of the polymer/Fe2O3 composite with evacuation of carbon from the system via COx gases released by carbo-reduction of Fe2O3. The material has significant activity in the reaction of catalytic decomposition of hydrogen peroxide in water solutions.

关键词： Composite materialsPorous carbonPolymersIron particles