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Crystal Structure of ZnCl<sub>3</sub>(Methyl-(2-Pyridin-2-yl-Ethyl)-Ammonium)

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American Journal of Analytical chemistry 2015年第3期6卷 189-195页

作者： Mahjouba Ben nasr Erwann Jeanneau chérif Ben nasr Université de Carthage Laboratoire de Chimie des Matériaux Faculté des Sciences de Bizerte Zarzouna Tunisie Centre Diffractométrie Henri Longchambon Université Claude Bernard Lyon 1 Villeurbanne France

A new Zn(II) complex with the monodentate ligand methyl-(2-pyridin-2-yl-ethyl)-ammonium, ZnCl3C8H13n2, has been prepared and characterized by single crystal X-ray diffraction. The Zn(II) ion is tetracoordinated by one nitrogen atom of organic ligand and three chlorine ligands. In the atomic arrangement, the ZnnCl3 tetrahedra form corrugated chains extending along the b-axis. The organic entities are located between these chains through n-H···Cl, C-H···Cl and C-H···n hydrogen bonds to form layers parallel to (b, c) plan. Among these hydrogen bonds two are bifurcated.

关键词： X-Ray Diffraction Coordination Compound Zinc Complex

Master of one trade:Arbutus unedo relies on plasticity to persist under habitats differing in water availability

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Journal of Plant Ecology 2017年第5期10卷 869-881页

作者： Xabier Santiso Rubén Retuerto Área de Ecología Facultad de BiologíaCampus VidaUniversidade de Santiago de Compostela15782 Santiago de CompostelaSpain

Aims the limited water supply in the Mediterranean Basin will be exacerbated in the immediate future as result of severe drought ***,the study of the intraspecific variability in functional traits of plant species is important,because such variability modulates species’***,we aimed to analyse the variability in plasticity of physiological and structural traits of Arbutus unedo *** response to water availability and to determine whether the levels of phenotypic plasticity varied in plants of different *** We kept two sets of plants under contrasted water regimes(high water and low water)and calculated a phenotypic plasticity index to determine the plastic response to water *** compared the response among kind of traits and *** also per-formed analysis of variance to assess the trait and provenance *** Findings We found that biomass and key physiological traits decrease under drought conditions,while the water use efficiency *** differed between groups of traits,being higher in structural and gas exchange parameters,but the provenance did not account for signifi-cant variation in *** has evolved a‘good saver’strat-egy,involving decreasing growth and water use-when this resource is unavailable-together with the dissipation of excess of radiation that it cannot *** homogeneous response between provenances may be the result of a canalization *** strategy,based on a high degree of plasticity,is a probable determining factor in the success of the species over its wide range of environmental conditions and will be critical to withstand the ongoing environmental changes.

关键词： adaptation canalization contrasted provenances drought global change phenotypic plasticity

Stem cell-based approaches: Possible route to hearing restoration?

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World Journal of Stem Cells 2020年第6期12卷 422-437页

作者： María Beatriz Durán-Alonso Institute of Biology and Molecular Genetics University of ValladolidValladolid 47003Spain

Disabling hearing loss is the most common sensorineural disability *** affects around 466 million people and its incidence is expected to rise to around 900 million people by 2050,according to World Health Organization *** cases of hearing impairment are due to the degeneration of hair cells(HCs)in the cochlea,mechano-receptors that transduce incoming sound information into electrical signals that are sent to the *** to these cells is mainly caused by exposure to aminoglycoside antibiotics and to some anti-cancer drugs such as cisplatin,loud sounds,age,infections and genetic *** deficits may also result from damage to the spiral ganglion neurons that innervate cochlear *** from what is observed in avian and nonmammalian species,there is no regeneration of missing sensory cell types in the adult mammalian cochlea,what makes hearing loss an irreversible *** review summarizes the research that has been conducted with the aim of developing cell-based strategies that lead to sensory cell replacement in the adult cochlea and,ultimately,to hearing *** main lines of research are discussed,one directed toward the transplantation of exogenous replacement cells into the damaged tissue,and another that aims at reactivating the regenerative potential of putative progenitor cells in the adult inner *** from some of the studies that have been conducted are presented and the advantages and drawbacks of the various approaches discussed.

关键词： Hearing loss Cochlear hair cells Spiral ganglion neurons Cell regeneration Adult stem cells Cell transplantation

Thermodynamic analysis on synthesis process of diamond

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Journal of Central South University 2001年第3期13卷 156-160页

作者： YI Jian-hong, PEnG Yuan-dong (State Key Laboratory for Powder Metallurgy, Central South University, changsha 410083, china) State Key Laboratory for Powder Metallurgy Central South University Changsha China

Based upon the thermodynamic analysis of the nucleation of d iamond crystal, the effects of synthesis temperature and pressure on the nucleat ion of diamond crystal, diamond growth and output of diamond crystal, particle s ize and strength were discussed. The results show that the excess pressure has a n important effect on the critical radius of nucleation and thermodynamic b a rrier in the formation of a critical nucleus. Considering the excess pressure, t he expression of diamond nucleation rate was obtained.

关键词： diamond synthesis pressure temperature nucleation growth

Past,present,and future of long-term treatment for hepatitis B virus

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World Journal of Gastroenterology 2023年第25期29卷 3964-3983页

作者： Teresa Broquetas José A Carrión Liver Section Gastroenterology DepartmentHospital del MarBarcelona 08003Spain Institut Hospital del Mar D’Investigacions Mèdiques PSMARBarcelona 08003Spain Universitat Pompeu Fabra Facultat de Ciències de la Salut i de la VidaBarcelona 08003Spain

The estimated world prevalence of hepatitis B virus(HBV)infection is 316 *** infection was identified in 1963 and nowadays is a major cause of cirrhosis and hepatocellular carcinoma(HCC)despite universal vaccination programs,and effective antiviral ***-term administration of nucleos(t)ide analogues(nA)has been the treatment of choice for chronic hepatitis B during the last *** nA has shown a good safety profile and high efficacy in controlling viral replication,improving histology,and decreasing the HCC incidence,decompensation,and ***,the low probability of HBV surface antigen seroclearance made necessary an indefinite *** knowledge,in recent years,about the different phases of the viral cycle,and the new insights into the role of the immune system have yielded an increase in new therapeutic ***,several clinical trials evaluating combinations of new drugs with different mechanisms of action are ongoing with promising *** integrative literature review aims to assess the knowledge and major advances from the past of hepatitis B,the present of nA treatment and withdrawal,and the future perspectives with combined molecules to achieve a functional cure.

关键词： Hepatitis B Therapy Antigen Functional cure Antiviral agents Drug development

The prognostic role of high-sensitivity C-reactive protein in patients with acute myocardial infarction

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Journal of Geriatric Cardiology 2020年第7期17卷 379-383页

作者： Ekaterina A Polyakova Evgeny n Mikhaylov Department of Faculty Therapy Pavlov First Saint-Petersburg State Medical UniversitySaint-PetersburgRussian Federation Metabolic Syndrome Laboratory Institute of EndocrinologyAlmazov National Medical Research CentreSaint-PetersburgRussian Federation neuromodulation Lab and Arrhythmia Department Almazov National Medical Research CentreSaint PetersburgRussian Federation Department of Bioengineering Systems Saint-Petersburg Electrotechnical University“LETI”Saint PetersburgRussian Federation

1 Introduction Inflammation is one of the main mechanisms in the pathogenesis of atherosclerosis,and the interest to the evaluation of inflammatory biomarkers in coronary artery disease(CAD)has been increasing over the last decade.[1,2]Destabilization of chronic artery plaques,which leads to acute coronary syndromes,has been associated with inflammatory status.[1,3]。

关键词： Atrial fibrillation Coronary artery disease High sensitive C-reactive protein Myocardial infarction Prognosis

Efficient destruction of sodium cyanide by thermal decomposition with addition of ferric oxide

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Transactions of nonferrous Metals Society of china 2021年第4期31卷 1113-1126页

作者： Kai-wei dong Feng XIE Wei WAnG Yong-feng chAnG chun-lin chEn Xiao-wei GU School of Metallurgy Northeastern UniversityShenyang 110819China CSIRO Minerals Resources ClaytonVictoria 3168Australia School of Resources and Civil Engineering Northeastern UniversityShenyang 110819China Science and Technology Innovation Center of Smart Water and Resource Environment Northeastern UniversityShenyang 110819China

Efficient destruction of cyanide by thermal decomposition with ferric oxide addition was proposed. The mechanism of destruction of sodium cyanide with or without ferric oxide addition under various conditions was examined by XRD, DSC-TG, and chemical analysis technologies. In the absence of ferric oxide, sodium cyanide decomposes at 587.4 ℃ in air and 879.2 ℃ in argon atmosphere. In the presence of ferric oxide, about 60% of sodium cyanide decomposes at 350 ℃ for 30 min in argon, while almost all sodium cyanide decomposes within 30 min in air or O2 with mass ratio of ferric oxide to sodium cyanide of 1:1. The increase of ferric oxide addition, temperature, and heating time facilitates the destruction of sodium cyanide. It is believed that with ferric oxide addition, naCn reacts with Fe2O3 to form na4Fe(Cn)6, na2CO3, nanO2 and Fe3O4 in argon. naCn decomposes into naCnO, na4Fe(Cn)6, minor nanO2, and the formed naCnO and na4Fe(Cn)6 further decompose into na2CO3, CO2, n2, FeOx, and minor nOx in air or O2.

关键词： cyanide destruction thermal decomposition ferric oxide catalytic oxidation sodium cyanide

A note on Bell-Based Bernoulli and Euler Polynomials of Complex Variable

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Computer Modeling in Engineering & Sciences 2023年第4期135卷 187-209页

作者： n.Alam W.A.Khan S.Obeidat G.Muhiuddin n.S.Diab H.n.Zaidi A.Altaleb L.Bachioua Department of Basic Sciences Deanship of Preparatory YearUniversity of Ha’ilHa’il2440Saudi Arabia Department of Mathematics and natural Sciences Prince Mohammad Bin Fahd UniversityAl Khobar31952Saudi Arabia Department of Mathematics Faculty of ScienceUniversity of TabukTabuk71491Saudi Arabia

In this article,we construct the generating functions for new families of special polynomials including two parametric kinds of Bell-based Bernoulli and Euler *** fundamental properties of these functions are *** using these generating functions and some identities,relations among trigonometric functions and two parametric kinds of Bell-based Bernoulli and Euler polynomials,Stirling numbers are *** formulae for these polynomials are *** a partial derivative operator to these generating functions,some derivative formulae and finite combinatorial sums involving the aforementioned polynomials and numbers are also *** addition,some remarks and observations on these polynomials are given.

关键词： Bernoulli polynomials euler polynomials bell polynomials stirling numbers

Determination of 18 Kinds of Amino Acids in Fresh Tea Leaves by HPLC Coupled with Pre-column Derivatization

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Asian Agricultural Research 2018年第2期10卷 55-58,63页

作者： Shangwen dong Tengfei LIU Minghui dong Suzhou no. 10 High School of Jiangsu Province Suzhou 215000 China Suzhou Academy of Agricultural Sciences Suzhou 215155 China

A rapid and accurate quantitative method of high performance liquid chromatography( HPLC) with fluorescence detector has been developed for the analysis of 18 kinds of amino acids in fresh tea leaves. The samples were minced and mixed,and extracted with ultra pure water at 90℃ for 20 min. The 6-aminoquinolyl n-hydroxy-succinimidyl carbamate( AQC) was used as pre-column derivatization reagent. Gradient HPLC separation was performed on a C_(18) column( Symmetry C_(18),3. 9 mm × 15 cm,4 μm). Good linearity between concentrations and peak areas was achieved in the concentration range of 5. 0-250 μmol/L for 18 kinds of amino acids. The method was validated by the analysis of five replicates. The 18 kinds of amino acid standards were spiked in fresh tea leaf samples and the average recovery rate was 86. 25%-109. 05% with relative standard deviations( n = 5) ranging from 6. 03% to 10. 56%. The limit of detection( LOD) for the analytes was0. 05-1. 27 μmol/L. The method was successfully applied to the analysis of the 18 kinds of amino acids in fresh tea leaves from east dongting and west dongting mountains in Suzhou. The results indicate that the method is simple,rapid,precise and reliable.

关键词： Fresh tea leaves Free amino acids Pre-column derivatization High performance liquid chromatography(HPLC)