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Influences of spinel type and polymeric surfactants on the size evolution of colloidal magnetic nanocrystals （MFe2O4, M = Fe, Mn）

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Frontiers of Chemical Science and Engineering 2014年第3期8卷 378-385页

作者： Tahereh r. BASTAMI Mohammad H. ENTEZArI Chiwai KWONG Shizhang QIAO Department of Chemical Engineering Quchan University of Advanced Technology Quchan 94771 Iran Department of Chemistry Verdowsi University of Mashhad Mashhad-91775 Iran School of Chemical Engineering The University of Adelaide SA 5005 Australia

Two types of polymeric surfactants, PEG300 and PVP40000, were used for the preparation of magnetic ferrite MFe2O4 （M- Mn, Fe） colloidal nanocrystals using a solvothermal reaction method. The effect of spinel type effect on the size evolution of various nanoparticles was investigated. It was found that Fe3O4 nanoparticles exhibited higher crystalinity and size evolution than MnFe2O4 nanoparticles with use of the two surfactants. It is proposed that this observation is due to fewer tendencies of surfactants on the surface of Fe3O4 building blocks nanoparticles than MnFe2O4. Less amounts of surfactant or capping agent on the surface of nanoparticles lead to the higher crystalibity and larger size. It is also suggested that the type of spinel （normal or inverted spinel） plays a key role on the affinity of the polymeric surfactant on the surface of building blocks.

关键词： spinel type polymeric surfactant size evolution mangnetic ferrite nanoparticle

Changes of the cytokine profile in inflammatory bowel diseases

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World Journal of Gastroenterology 2012年第41期18卷 5848-5861页

作者： Gyrgyi Mzes Béla Molnár Zsolt Tulassay Ferenc Sipos 2nd Department of Internal Medicine Semmelweis University1088 BudapestHungary Molecular Medicine research Unit Hungarian Academy of Sciences1051 BudapestHungary

Cytokines are indispensable signals of the mucosaassociated immune system for maintaining normal gut *** imbalance of their profile in favour of inflammation initiation may lead to disease states,such as that is observed in inflammatory bowel diseases(IBD).Although Crohn's disease(CD) is often described as a prototype of T-helper 1-type diseases,and ulcerative colitis(UC) is traditionally viewed as a T-helper 2-mediated condition,the classic paradigm,which categorises cytokines into pro-and anti-inflammatory groups,has recently been *** inflammation regulatory pathways may not be mutually exclusive as individual cytokines can have diverse and even opposing functions in various clinical and immunological *** the less there are many common immunological responses in IBD that are mediated by *** they regulate and influence the development,course and recurrence of the inflammatory process,the concrete pathogenic role of these small signaling molecules is sometimes not unambiguous in the subtypes of the *** aim is to review the current information about pro-and anti-inflammatory effects of traditionally studied and recently discovered cytokines in the pathogenesis of UC and *** better understanding of their production and functional activity may lead to the development of new therapeutic modalities.

关键词：细胞因子肠道疾病炎症信号分子抗炎作用免疫系统个人资料相互排斥

3D Photo-Fabrication for Tissue Engineering and Drug Delivery

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Engineering 2015年第1期1卷 90-112页

作者： rúben F.Pereira Paulo J.Bártolo Centre for rapid and Sustainable Product Development (CDrsp) Polytechnic Institute of Leiria Instituto de Investiga??o e Inova??o em Saúde (I3S) Universidade do Porto Instituto Nacional de Engenharia Biomédica (INEB) Universidade do Porto Instituto de Ciências Biomédicas Abel Salazar (ICBAS) Universidade do Porto School of Mechanical Aerospace and Civil EngineeringUniversity of Manchester Manchester Institute of Biotechnology University of Manchester

The most promising strategies in tissue engineering involve the integration of a triad of biomaterials, living cells, and biologically active molecules to engineer synthetic environments that closely mimic the healing milieu present in human tissues, and that stimulate tissue repair and regeneration. To be clinically effective, these environments must replicate, as closely as possible, the main characteristics of the native extracellular matrix(ECM) on a cellular and subcellular scale. Photo-fabrication techniques have already been used to generate 3D environments with precise architectures and heterogeneous composition, through a multi-layer procedure involving the selective photocrosslinking reaction of a light-sensitive prepolymer. Cells and therapeutic molecules can be included in the initial hydrogel precursor solution, and processed into 3D constructs. recently, photofabrication has also been explored to dynamically modulate hydrogel features in real time, providing enhanced control of cell fate and delivery of bioactive compounds. This paper focuses on the use of 3D photo-fabrication techniques to produce advanced constructs for tissue regeneration and drug delivery applications. State-of-the-art photo-fabrication techniques are described, with emphasis on the operating principles and biofabrication strategies to create spatially controlled patterns of cells and bioactive factors. Considering its fast processing, spatiotemporal control, high resolution, and accuracy, photo-fabrication is assuming a critical role in the design of sophisticated 3D constructs. This technology is capable of providing appropriate environments for tissue regeneration, and regulating the spatiotemporal delivery of therapeutics.

关键词：三维结构照片制作组织工程传递药物生物活性分子生物活性化合物合成环境

A　STUDY　OF　THE　DISPLACEMENT　MECHANICS　FOr　NONNEWTONIAN　FLUIDS　AND　ITS　APPLICATION　IN　THE　WELL　CEMENTING　TECHNIQUES

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Journal of Hydrodynamics 1995年第3期7卷 107-110页

作者： Zheng Yong-gang(University of Petroleum, Dongying 257062,P.r.China) Univ of Petroleum Dongying China

The displacement mechanics of non-Newtonian fluid in an eccentric annulus was investigated by using the slot flow model. Based on recognizing and analysing the displacement processes, the mathematical models of axial laminar displacement were proposed. The turbulent flow theory has also been studied systematically. Using the numerical method, the models were numerically solved. The theoretical models have been examined, it is found that these models are basically identical with the experimental data.

关键词： ITS FLUIDS APPLICATION AND

Giant pandas use odor cues to discriminate kin from nonkin

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Current Zoology 2016年第4期62卷 333-336页

作者： Oranit GILAD ronald r. SWAISGOOD Megan A. OWEN Xiaoping ZHOU Department of Biology Texas A&M University College Station TX 77843 USA Institute for Conservation research San Diego Zoo Global Escondido CA 92027 USA China research and Conservation Center for the Giant Panda Wolong Sichuan 623006 China

Sociality is an important factor in both the mechanism and function of kin recognition, yet it is little explored in solitary species. While there may be future opportunities for nepotistic functions of kin discrimination among solitary species, the ability to discriminate kin from nonkin may still have important roles in social regulation. The solitary giant panda offers a good model system to explore kin discrimination in a solitary mammal. As kin discrimination in many other mammals is olfactorily mediated, we investigated whether giant pandas are able to discriminate odor cues from daughters even after months and years of separation. Our results indicate that giant pandas are capable of discriminating between kin and nonkin using odor cues available in urine and body odor. Daughters preferentially investigated the odors of unrelated adult female pandas over the odors of their mothers, and mothers spent more time investigating the odors of unrelated age-matched female pandas over those from their daughters. Because these studies were conducted months or years after the mother-daughter period of dependency ended, it is still unclear what mechanism is used for recognition. Long-term olfactory memories and phenotype matching should both be considered, and further studies are required for such determination.

关键词： chemical communication giant panda kin discrimination

Projections of the impacts of climate change on the water deficit and on the precipitation erosive indexes in Mantaro river Basin, Peru

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Journal of Mountain Science 2018年第2期15卷 264-279页

作者： Sly C.WONGCHUIG Carlos r.MELLO Sin C.CHOU Hydraulics Institute research Federal University of Rio Grande do Sul Soil and Water Engineering Federal University of Lavras Brazilian Weather research and Forecast National Spatial Research Institute (INPE)

Projections of climate change are essential to guide sustainable development plans in the tropical Andean countries such as Peru. This study assessed the projections of precipitation and potential evaporation, rain erosive potential, and precipitation concentration in the Mantaro river Basin, in the Peruvian Andes, which is important for agriculture and energy production in Peru. We assumed the Intergovernmental Panel on Climate Change(IPCC)A_1B greenhouse gas emission scenario and simulated the global climate change by the HadCM_3 global climate model. Due to the steepness of the mountain slopes and the narrowness of the river valley, this study uses the downscaling of the global model simulations by the regional Eta model down to 20-km resolution. The downscaling projections show decrease in the monthly precipitation with respect to the baseline period, especially during the rainy season,between February and April, until the end of the 21st century. Meanwhile, a progressive increase in the monthly evaporation from the baseline period is projected. The Modified Fournier Index(MFI) shows a statistically significant downward trend in the Mantaro river Basin, which suggests a possible reduction in the rain erosive potential. The Precipitation Concentration Index(PCI) shows a statistically significant increasing trend, which indicates increasingly more irregular temporal distribution of precipitation towards the end of the century. The results of this study allow us to conclude that there should be a gradual increase in water deficit and precipitation concentration. Both changes can be negative for agriculture, power generation, and water supply in the Mantaro river Basin in Peru.

关键词：全球气候变化降水秘鲁设计索引腐蚀全球气候模型安第斯山脉

THE HADAMArD INEQUALITY FOr CONVEX FUNCTION VIA FrACTIONAL INTEGrALS

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Acta Mathematica Scientia 2013年第5期33卷 1293-1299页

作者： M.E.ZDEMr S.S.DrAGOMIr C.YILDIZ Department of Mathematics K.K.Education Faculty Atatürk University School of Engineering & Science Victoria University

In this paper, we establish several inequalities for some differantiable mappings that are connected with the riemann-Liouville fractional integrals. The analysis used in the proofs is fairly elementary.

关键词： Hadamard's inequality convex functions power-mean inequality riemann-Liouville fractional integration

Quantification of human telomerase rNA(hTr)and human telomerase reverse transcriptase(hTErT)mrNA in testicular tissue of infertile patients

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Asian Journal of Andrology 2001年第4期3卷 263-270页

作者： Mark Schrader Markus Müller rüdiger Heicappell Bernd Straub Kurt Miller Department of Urology Universitatsklinikum Benjamin FranklinFreie Universitat BerlinHindenburgdamm 3012200 BerlinGermany

Aim:To evaluate the quantitative detection of human telomerase rNA(hTr)and human telomerase reverse tran-scriptase(hTErT)mrNA as diagnostic parameters in the workup of testicular tissue specimens from patients presentingwith non-obstructive ***:hTr and hTErT mrNA expression were quantified in 38 cryopre-served testicular tissue specimens by fluorescence real-time reverse transcription-polymerase chain reaction(rT-PCr)in a LightCycler(r).This was paralleled by conventional histological workup in all tissue specimens and additionalsemithin sectioning preparation in cases with maturation arrest(n=12)and Sertoli-cell-only syndrome(n=12).re-sults;The average normalized hTErT expression(N_(hTErT))was 131.9±48.0 copies(mean±SD)in tissue speci-mens with full spermatogenesis,N_(hTErT)=51.2±17.2 copies in those with maturation arrest and N_(hTErT)=2.7±2.4copies in those with Sertoli-cell-only syndrome(SCOS).The discriminant analysis showed that detection of N_(hTErT)(N_(hTr))had a predictive value of 86.8%(55.3%)for correct classification in one of the three histological ***;Our results demonstrate that quantitative detection of hTErT mrNA expression in testicular tissue en-ables a molecular-diagnostic classification of *** detection of hTErT in testicular biopsies isthus well suited for supplementing the histopathological evaluation.

关键词： spermatogenesis human telomerase reverse transcriptase human telomerase rNA fertility

Effects of Isotopic Concentrations on Thermodynamic Parameters of Deuterium-Tritium Mixtures

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Communications in Theoretical Physics 2013年第7期60卷 108-112页

作者： S.M. Motevalli M.r. Pahlavani M. Azimi Department of Nuclear Physics Faculty of Science University of Mazandaran

Thermodynamic estimation is still too much requested for scientific applications in spite of great advances in simulation methods for efficient determination of phase equilibrium of multi-component systems. In this work, thermodynamic properties of deuterium-tritium mixture in a wide range of temperatures and pressures have been predicted. Buckingham exp-6 potential has been utilized in calculations, based on statistical perturbation theory. The effects of various values of density, temperature and isotopic concentrations on pressure have been studied. Eventually, we have found out symmetrical effects of tritium concentration in deuterium-tritium mixtures.

关键词：热力学性质氚浓度混合物数浓度同位素氘科学应用模拟方法