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Melt Crystallization of Poly(butylene 2,6-naphthalate)

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Chinese Journal of Polymer Science 2020年第4期38卷 311-322,I0004页

作者： Qian Ding Michelina Soccio nadia Lotti Dario Cavallo Rene Androsch School of Packaging Design and Art Hunan University ofTechnologyZhuzhou 412007China Department ofCivil ChemicalEnvironmental and Materials EngineeringUniversity of BolognaVia Terracini 28Bologna 40131Italy Department of Chemistry and Industrial Chemistry University of GenovaViaDodecaneso31Genova 16146Italy Interdisciplinary Center for Transfer-oriented Research in Natural Sciences(IWE TFN) Martin Luther University Halle-WittenbergHalle/Saale 06099Germany

Poly(butylene 2,6-naphthalate)(PBN)is a crystallizable linear polyester containing a rigid naphthalene unit and flexible methylene spacer in the chemical repeat *** materials made of PBN exhibit excellent anti-abrasion and low friction properties,superior chemical resista nee,and outstanding gas barrier *** of the properties rely on the presence of crystals and the formatio n of a semicrystalline *** develop specific crystal structures and morphologies during cooling the melt,precise information about the melt-crystallization process is *** review article summarizes the current knowledge about the temperature-controlled crystal polymorphism of *** rather low supercooling of the melt,with decreasi ng crystal I izatio n temperature,0'-and a-crystals grow directly from the melt and organize in largely different spherulitic *** of a-crystals at high supercooling may also proceed via intermediate formation of a transient monotropic liquid crystalline structure,then yielding a non-spherulitic semicrystalline *** of PBN is rather fast since its suppression requires cooling the melt at a rate higher than 6000 K-s_*** this reason,investigation of the two-step crystallization process at low temperatu res requires application of sophisticated experimental *** in elude temperatureresolved X-ray scattering techniques using fast detectors and synchrotron-based X-rays and fast scanning chip *** scanning chip calorimetry allows freezi ng the transie nt liquid-crystalline structure before its con version into a-crystals,by fast cooling to below its glass transition *** an alysis using polarized-light optical microscopy reveals its texture and X-ray scatteri ng con firms the smectic arrangement of the *** combination of a large variety of experimental techniques allows obtaining a complete picture about crystallization of PBN in the entire

关键词： Poly(butylene 2,6-naphthalate) Crystallization Polymorphism Semicrystalline morphology

Impact of zinc and arginine on antioxidant status of weanling piglets raised under commercial conditions

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Animal Nutrition 2019年第3期5卷 227-233页

作者： nadia Bergeron Frédéric Guay Departement des Sciences Animales Université Laval

The effects of dietary zinc and L-arginine supplements on the weight gain,feed efficiency,antioxidant capacity and oxidative status of weanling piglets raised under commercial conditions were examined.A total of 288 piglets aged 21 d were fed for 15 d a diet supplemented or not with 2,500 mg/kg of zinc(provided as zinc oxide)and 1% L-arginine *** 4 treatments were distributed in a randomized complete block design with 6 initial body weight categories(12 animals per pen).Access to feed and water was ad *** were analyzed as a 2 x 2 factorial experiment using the SAS MIXED procedure,with zinc and arginine as the main independent *** collection day(d 8 and 15,samples were collected from the same 2 piglets in each pen before the morning feeding)was included as a third *** zinc supplement increased the average daily gain(ADG)from d 0 to 7.d 8 to 15 and d 0 to 15(0.289 vs.0.217 kg/d).average daily feed intake(ADFR)from d 8 to 15 and d 0 to 15(0.338 vs.0.279 kg/d)and the gain to feed(G:F)ratio from d 0 to 7 and d 0 to 15(0.86 vs.0.77)(P<0.001).Both supplements significantly decreased the malondialdehyde concentration(zinc:4.37 vs.3.91 μmol/L,P= 0.005;arginine:4.38 vs.3.89 μmol/L,P = 0.002).Total antioxidant capacity and reduced glutathione(GSH)increased from d 8 to 15(0.953 vs.1.391 μmol/L,2.22 vs.3.37 μmol/L,P<0.05)regardless of dietary *** and oxidized GSH concentrations on d 8 were higher in response to the combined supplements(zinc x arginine interaction.P<0.05).Piglets fed either Zn-supplemented diet had a lower haptoglobin serum concentration(509 vs.1.417 mg/L;P<0.001).In conclusion,the zinc supplement improved piglet growth performance(ADG and ADFI)and oxidative status(based on malondialdehyde concentration).The arginine supplement had a limited effect on growth performance and oxidative status under these conditions.

关键词： Zinc Arginine Weanling piglets Antioxidant status Growth performance

Essential oils of Origanum compactum increase membrane permeability,disturb cell membrane integrity,and suppress quorum-sensing phenotype in bacteria

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Journal of Pharmaceutical Analysis 2019年第5期9卷 301-311页

作者： Abdelhakim Bouyahya Jamal Abrini nadia Dakka Youssef Bakri Laboratory of Human Pathologies Biology Department of Biology Faculty of Sciences and Genomic Center of Human Pathologies Faculty of Medicine and Pharmacy Mohammed V University Rabat Morocco Biology and Health Laboratory Department of Biology Faculty of Science Abdelmalek Essaadi University Tetouan Morocco

The aim of this study was to investigate antibacterial activity of Origanum compactum essential oils collected at three phenological stages on Escherichia coli and Bacillus subtilis. The antibacterial activity was evaluated using the agar-well diffusion assay. The MIC and MBC values were determined using the micro-dilution assay. The investigation of the antibacterial action was carried out by the evaluation of the effect of O. compactum essential oils on the antibacterial kinetic growth, the integrity of cell membrane and permeability of the cell membrane. The anti-quorum sensing activity was tested by the inhibition of the biofilm formation. The findings of this study showed that O. compactum essential oil has potent antibacterial activities against E. coli and B. subtilis. The lowest inhibition value against B. subtilis was obtained with O. compactum essential oil at the post-flowering stage (MIC=MBC=0.0312%(v/v)). The antibacterial mechanisms of O. compactum essential oils are related to the disturbing of the cell membrane integrity and the increasing of the membrane permeability, which leads to the leakage of genetic materials (DNA and RNA). Moreover, O. compactum essential oils inhibited the formation of the biofilms, a phenotype that has been known to be quorum sensing regulated.

关键词： Origanum compactum Essential oil Antibacterial action Cell membrane Quorum sensing inhibition

Salinity effect on the compaction behaviour,matric suction,stiffness and microstructure of a silty soil

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Journal of Rock Mechanics and Geotechnical Engineering 2021年第4期13卷 855-863页

作者： Zi Ying Yu-Jun Cui nadia Benahmed Myriam Duc Ecole des Ponts ParisTech Laboratoire Navier/CERMES6-8 av.Blaise PascalCite DescartesChamps-sur-MarneMarne-la-Vallee cedex 277455France INRAE Aix Marseille UnivRECOVEREquipe G2DR3275 route CezanneCS 40061Aix-en-Provence13182France Universite Gustave Eiffel IFSTTAR/GERS/SRO14-20 boulevard NewtonChamps-sur-MarneMarne-la-Vallee77447France

To better understand the salinity effect on the compaction behaviour of soil,standard Proctor compaction test was conducted on soil samples with different *** suction and small-strain shear modulus,G_(max),were determined and pore size distribution was also investigated on samples statically compacted at different water *** showed that with the decrease of soil salinity from initial value of 2.1‰(g of salt/kg of dry soil)to zero,the maximum dry density increased and the optimum water content decreased,whereas there was no significant change with the increase of soil salinity from 2.1‰ to 6.76‰.Interestingly,it was observed that G_(max) also decreased when the soil salinity decreased from initial value of 2.1‰ to zero and kept almost constant when the soil salinity increased from 2.1‰ to 6.76‰,for dry samples with similar matric suction and also for samples compacted at optimum state and on wet side whose matric suctions were slightly different due to the difference in remoulded water ***,the effect of salinity on compaction behaviour and G_(max) decreased for samples compacted from dry side to wet *** pore size distribution exhibited bi-modal characteristics with two populations of micro-and macro-pores not only for samples compacted on dry side and at optimum state,but also for those compacted on wet *** examination showed that the modal size of micro-pores shifted to lower values and that of macro-pores shifted to higher values for saline soil compared to the soil without salt.

关键词： Silts Compaction Suction Stiffness Microstructure

Application of Response Surface Methodology for Optimization of Cadmium Ion Removal from an Aqueous Solution by Eggshell Powder

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Chemical Research in Chinese Universities 2018年第2期34卷 302-310页

作者： SABAH Hajji THOURAYA Turki MELEK Hajji nadia Mzoughi Natural Water Treatment Laboratory Water Researches and Technologies Centre of Borj Cedria(CERTE) Technopark of Borj Cedria Soliman 8020 Tunisia Faculty of Science of Bizerte University of Carthage Jarzouna-Bizerte 7000 Tunisia Research Unit: Electrochemistry Materials and Environment Preparatory Institute forEngineering Studies of Kairouan University of Kairouan Kairouan 3100 Tunisia High Institute of Environmental Sciences and Technologies of Borj Cedria Environmental Sciences and Technologies Laboratory University of Carthage Hammam Lif 2050 Tunisia

The removal of cadmium（Cd） from synthetic solutions by batch adsorption process was performed using eggshell powder, which is mainly composed of calcite（CaCO3）. In order to optimize the adsorption process, a re- sponse surface methodology（RSM） based on Central Composite Design（CCD） was applied. Developed model for Cd removal yields（R, %） response was statistically validated by variance analysis（ANOVA） which showed a high de- termination coefficient value（R2=0.9889）. According to Minitab software, the optimal conditions were found at tem- perature of 44℃, eggshell adsorbent dose of 2.98 g, initial Cd concentration of 36.74 mg/L and initial pH of 7. Under these conditions, the Cd removal yield was 98.76%. The deviation value of 1.24% confirms the validity of the model for the adsorption process optimization. The adsorption isotherm has been described by a Freundlich model. In addition, the predominant sorption mechanisms are the chemisorptions or precipitation（non-reversible） and ion ex- change（reversible）.

关键词： Response surface methodology Cadmium Eggshell Sorption Desorpfion Freundlich model

Photo-induced reorientation of molecules in dye micro crystals

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Chinese Optics Letters 2006年第1期4卷 43-44页

作者： Tariel D. Ebralidze nadia A. Ebralidze Institute of Cybernetics Georgian Academy of Sciences Sandro Euli Str. Tbilisi 186 Georgia USA

Upon massive generation of anisotropic grains of azo dye methyl orange in a gelatin film exposed to active polarized light, a cluster of micro crystals with optical axes of similar orientations has been produced. The ... 详细信息

关键词： Photo-induced reorientation of molecules in dye micro crystals

Tumor rupture during surgery for gastrointestinal stromal tumors: Pay attention!

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World Journal of Gastroenterology 2013年第12期19卷 2009-2010页

作者： nadia Peparini Piero Chirletti Azienda Sanitaria Locale Roma H Department of Surgical Sciences Sapienza University of Rome

In a recently published letter to the editor, we debated the proposal by Coccolini et al to treat gastrointestinal stromal tumors (GISTs) of the esophagogastric junction with enucleation and, if indicated, adjuvant therapy. We highlighted that, because the prognostic impact of a T1 high-mitotic rate esophageal GIST is worse than that of a T1 high-mitotic rate gastric GIST, enucleation may not be adequate surgery for esophagogastric GISTs with a high mitotic rate. In rebuttal, Coccolini et al pointed out the possible bias in assessment of the mitotic rates due to the lack of standardized methods and underlined that the site and features of the tumor need to be carefully considered in evaluation of the risk-benefit balance. Here we confirm that, apart from the problematic issue of mitotic counting, enucleation should not be indicated for GISTs at any site to reduce the risk of tumor rupture, which has been recently considered to be an unfavorable prognostic factor, and to avoid microscopic residual tumor.

关键词： Gastrointestinal stromal tumor Esophagogastric junction Surgery Resection Enucleation

Insight into the interaction of inhaled corticosteroids with human serum albumin: A spectroscopic-based study

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Journal of Pharmaceutical Analysis 2018年第1期8卷 37-44页

作者： Carlotta Pontremoli nadia Barbero Guido Viscardi Sonja Visentin Department of Applied Science and Technology (DISAT) Politecnico of Torino Department of Chemistry and NIS Interdepartmental Centre University of Torino Molecular Biotechnology and Health Sciences Department University of Torino

It is well known that the safety and efficacy profile of an inhaled cortocosteroid(ICS) is influenced by the pharmacokinetic properties and associated pharmacodynamic effects of the drug. Freely circulating,protein unbound, and active ICS can cause systemic adverse effects. Therefore, a detailed investigation of drug-protein interaction could be of great interest to understand the pharmacokinetic behaviour of corticosteroids and for the design of new analogues with effective pharmacological properties. In the present work, the interaction between some corticosteroids and human serum albumin(HSA) has been studied by spectroscopic approaches. UV–Vis spectroscopy confirmed that all the investigated corticosteroids can bind to HSA forming a protein-drug complex. The intrinsic fluorescence of HSA was quenched by all the investigated drugs, which was rationalized in terms of a static quenching mechanism. The thermodynamic parameters determined by the Van't Hoff analysis of the binding constants(negative ΔH and ΔS values) clearly indicate thathydrogen bonds and van der Waals forces play a major role in the binding process between albumin and betamethasone, flunisolide and prednisolone, while hydrophobic forces may play a major role in stabilizing albumin-triamcinolone complexes.

关键词： Human serum albumin Inhaled corticosteroids Fluorescence spectroscopy Fluorescence resonance energy transfer(FRET)

Determining osmotic suction through electrical conductivity for unsaturated low-plasticity soils

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第6期14卷 1946-1955页

作者： Zi Ying nadia Benahmed Yu-Jun Cui Myriam Duc Ecole des Ponts ParisTech Laboratoire Navier/CERMES6-8 Av.Blaise PascalCitéDescartesChamps-sur-MarneMarne-la-ValléeCedex277455France INRAE Aix Marseille UniversityUnitéde Recherche RECOVER3275 Route CézanneAix-en-Provence13182France UniversitéGustave Eiffel IFSTTAR/GERS/SRO14-20 Boulevard NewtonChamps-sur-MarneMarne-la-Vallée77447France

Determining osmotic suction from the electrical conductivity(EC)of soil pore water was widely reported in the ***,while dealing with unsaturated soils,they do not have enough soil pore water to be extracted for a reliable measurement of *** this paper,the chilled-mirror dew-point hygrometer and contact filter paper method were used to determine the total and matric suctions for low-plasticity soils with different salinities(0.05‰,2.1‰,and 6.76‰).A new piecewise function was proposed to calculate the osmotic suction,with the piecewise point corresponding to the first occurrence of precipitated salt in mixed salt solutions(synthetic seawater).EC,ion and salt concentrations used for osmotic suction calculation were transformed from the established relationships of mixed salt solution instead of experimental *** calculated osmotic suction by the proposed equation and the equations in the literature was compared with the indirectly measured one(the difference between the measured total and matric suctions).Results showed that the calculated osmotic suction,especially the one calculated using the proposed function,was in fair agreement with the indirectly measured data(especially for specimens with higher salinity of 6.76‰),suggesting that the transformation of EC and concentrations from the established relationship is a good alternative to direct measurement for lowplasticity *** particular,the proposed method could be applied to unsaturated low-plasticity soils which do not have enough soil pore water for a proper EC measurement.

关键词： Unsaturated soils Mixed salt solutions Osmotic suction Electrical conductivity(EC)