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Neurological consequences of systemic inflammation in the premature neonate

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Neural Regeneration Research 2017年第6期12卷 890-896页

作者： Aparna Patra Hong Huang john A.Bauer Peter j.Giannone OMNI Academic Service Line and Division of Neonatology Department of Pediatrics Kentucky Children's Hospital College of MedicineUniversity of Kentucky

Despite substantial progress in neonatal care over the past two decades leading to improved survival of extremely premature infants, extreme prematurity continues to be associated with long term neurodevelopmental impairments. Cerebral white matter injury is the predominant form of insult in preterm brain leading to adverse neurological consequences. Such brain injury pattern and unfavorable neurologic sequelae is commonly encountered in premature infants exposed to systemic inflammatory states such as clinical or culture proven sepsis with or without evidence of meningitis, prolonged mechanical ventilation, bronchopulmonary dysplasia, necrotizing enterocolitis and chorioamnionitis. Underlying mechanisms may include cytokine mediated processes without direct entry of pathogens into the brain, developmental differences in immune response and complex neurovascular barrier system that play a critical role in regulating the cerebral response to various systemic inflammatory insults in premature infants. Understanding of these pathologic mechanisms and clinical correlates of such injury based on serum biomarkers or brain imaging findings on magnetic resonance imaging will pave way for future research and translational therapeutic opportunities for the developing brain.

关键词： premature consequences inflammation prematurity extremely translational dysplasia sepsis necrotizing neurological

Genetic algorithm optimization for finned channel performance

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Applied Mathematics and Mechanics(English Edition) 2007年第12期28卷 1597-1604页

作者： S.S.Mousavi K.Hooman S.j.Mousavi Production Department SAIPA CompanyTehranIran School of Engineering the University of QueenslandBrisbaneAustralia Knowledge Engineering Research Center Aerospace Industrial OrganizationTehranIran

Compared to a smooth channel, a finned channel provides a higher heat transfer coefficient; increasing the fin height enhances the heat transfer. However, this heat transfer enhancement is associated with an increase in the pressure drop. this leads to an increased pumping power requirement so that one may seek an optimum design for such systems. the main goal of this paper is to define the exact location and size of fins in such a way that a minimal pressure drop coincides with an optimal heat transfer based on the genetic algorithm. Each fin arrangement is considered a solution to the problem （an individual for genetic algorithm）. An initial population is generated randomly at the first step. then the algorithm has been searched among these solutions and made new solutions iteratively by its functions to find an optimum design as reported in this article.

关键词： Nusselt number pressure drop genetic algorithm optimum design baffle

Crystal structure and magnetic properties of YbZn_(0.7)In_(1.3)

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journal of Rare Earths 2011年第10期29卷 943-945页

作者： Yu.Verbovytskyy L.C.j.Pereira A.P.Gon alves Department of Chemistry Nuclear and Technological InstituteNational Rd.102686-953SacavémPortugal

the new ternary YbZn0.7Inl.3 compound was synthesized in evacuated quartz ampoules at 900 ℃, followed by annealing at 400 ℃. It crystallized in the UHg2 structure type with a=0.47934（5） nm, c=0.36955（5） nm, V=0.073535（15） nm3. the shortest distances between the atoms in this structure were equal to 0.3696 nm （Yb-Yb）, 0.3328 nm （Yb-M） and 0.2767 nm （M M）, respectively. Magnetization measurements indicated that the title compound exhibited a paramagnetic behavior down to 2 K, with antiferromagnetic-like interactions. Calculated magnetic moment for YbZn0.7inl.3 （μeft =3.86μB/Yb） could indicate mixed valence state of Yb.

关键词： ytterbium intermetallics crystal structure magnetic measurements rare earths

A quasi-crystal model of collagen microstructure based on SHG microscopy

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Chinese Optics Letters 2010年第2期8卷 213-216页

作者： Pu Xu Eleanor Kable Colin j. R. Sheppard Guy Cox Australian Key Centre for Microscopy and MicroanMysis University of Sydney NSW 2006 Australia Division of Bioengineering National University of Singapore Singapore 117576 Key Laboratory of Ecophysics Department of Physics Shihezi University Shihezi 832000 China

Second harmonic generation （SHG） results from molecules which are polarized by an external electric field often provided by an intense laser beam. the polarizability depends on firstly the intrinsic structural properties of the substance and hence the second-order nonlinear susceptibility, and secondly the intensity and polarization direction of the incident light. the polarization characteristics of the beam are therefore of interest. In this letter, we discuss some considerations in SHG microscopy of collagen when the incoming beam is circularly polarized, and present some supporting results as well as a numerical analysis. We propose a quasi-crystal model of collagen microstructure in an effort to further our understanding on this protein.

关键词： Collagen Electric fields Harmonic generation Nonlinear optics Numerical analysis Polarization Quasicrystals

Critical review of strategies for CO_2 delivery to large-scale microalgae cultures

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Chinese journal of Chemical Engineering 2018年第11期26卷 2219-2228页

作者： Qi Zheng Xiaoyin Xu Gregory j.O.Martin Sandra E.Kentish Peter Cook Centre for CCS Research Department of Chemical EngineeringThe University of Melbourne Algal Processing Group Department of Chemical EngineeringThe University of Melbourne

Microalgae have great, yet relatively untapped potential as a highly productive crop for the production of animal and aquaculture feed, biofuels, and nutraceutical products. Compared to conventional terrestrial crops they have a very fast growth rate and can be produced on non-arable land. During microalgae cultivation, carbon dioxide(CO_2) is supplied as the carbon source for photosynthesising microalgae. there are a number of potential CO_2 supplies including air, flue gas and purified CO_2. In addition, several strategies have been applied to the delivery of CO_2 to microalgae production systems, including directly bubbling CO_2-rich gas, microbubbles, porous membrane spargers and non-porous membrane contactors. this article provides a comparative analysis of the different CO_2 supply and delivery strategies and how they relate to each other.

关键词： Bubble Carbon dioxide Flue gas Bioreactors

Comparative study of 2mol% Li- and Mn-substituted lead-free potassium sodium niobate ceramics

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International journal of Minerals,Metallurgy and Materials 2014年第12期21卷 1241-1246页

作者： Asha Dahiya O.P.thakur j.K.juneja Sangeeta Singh Dipti School of Applied Sciences Netaji Subhas Institute of Technology Dwarka University of Delhi Department of Physics Hindu College Department of Physics Geeta Vidya Mandir Girls College School of Physics & Material Sciences Thapar University

the effect of Li and Mn substitution on the dielectric, ferroelectric and piezoelectric properties of lead free K0.5Na0.5NbO3 （KNN） was investigated. Samples were prepared using a conventional solid state reaction method. the sintefing temperature for all the samples was 1050℃. the optimum doping concentration for the enhancement of different properties without the introduction of any other co-dopants such as Ti, Sb, and La was investigated. X-ray diffraction analysis confirmed that all the samples crystallize in a single phase perovskite structure. the dielectric properties were investigated as a function of temperature and applied electric field frequency. Compared with Li-substituted KNN （KLNN）, Mn-substituted KNN （KMNN） exhibited a higher dielectric constant εmax （i.e., 4840） at its critical transition temperature Tc （i.e., 421℃） along with a lower value of tangent loss at 10 kHz and greater values of saturation polarisation Ps （i.e., 20.14 μC/cm^2） and remnant polarisation Pr （i.e., 15.48 μC/cm^2）. the piezoelectric constant （d33） of KMNN was 178 pC/N, which is comparable to that of lead-based hard ceramics. the results presented herein suggest that B-site or Mn substitution at the optimum concentration results in good enhancement of different properties required for materials used in memory devices and other applications.

关键词： ceramics dielectric properties ferroelectricity piezoelectricity substitution comparative study

Modern Microalloyed Steels

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journal of Iron and Steel Research International 2011年第S1期18卷 14-21页

作者： Garcia C Issac Suikkanen Pasi P Deardo Anthony j Basic Metals Processing Research Institute Department of Mechanical Engineering and Materials ScienceUniversity of PittsburghPittsburghPA 15261USA Department of Mechanical Engineering University of OuluBox 420090014 OuluFinland

the addition of microalloying elements (MAE) to low C-Mn-Si HSLA steels has led to many benefits to the producers,fabricators and *** improvements such as microstructural refinement,higher dislocation and sub-grain boundary densities and finer M-A-C distributions have led to higher strength,improved toughness and better *** improvements can often be traced to the MA *** steels for load-bearing applications,the combination of MAE with hardenability additions (Cr,Mo,B,etc.) and lower transformation temperatures has led to much higher strength levels than what were available a few years *** resulting nonpolygonal,bainitic and martensitic ferrite microstructures have not only higher strengths but also adequate levels of improved ductility and *** strip,plate and pipe applications have benefitted from these *** improvements have been found in the microalloyed forging steels,where the change from pearlite-ferrite to bainitic ferrite microstructures has led to higher strengths and improved high-cycle fatigue resistance,with little penalty in ductility and *** the cold rolled gauges,both the so-called Advanced High Strength Steels (DP,TRIP and Complex Phase Steels) and the martensitic direct-quenched and press-quenched steels,along with the Interstitial-Free steels,have benefited from MAE additions,especially in the very popular zinc-coated sheet *** paper will briefly review each of these topic areas,and the underlying physical metallurgy will be discussed.

关键词： microalloying vanadium HSLA steels bainite,linepipe thermomechanical processing

Analysis of High Frequency Data in Finance:A Survey

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Frontiers of Economics in China-Selected Publications from Chinese Universities 2020年第2期15卷 141-166页

作者： George j.jiang Guanzhong Pan Department of Finance and Management Science College of BusinessWashington State UniversityPullmanWA 99164USA School of Finance Yunnan University of Finance and EconomicsKunming 650221China

this study examines the use of high frequency data in finance,including volatility estimation and jump *** frequency data allows the construction of model-free volatility measures for asset *** variance is a consistent estimator of quadratic variation under mild regularity *** variation concepts,such as power variation and bipower variation,are useful and important for analyzing high frequency data when jumps are *** frequency data can also be used to test jumps in asset *** discuss three jump tests:bipower variation test,power variation test,and variance swap test in this *** presence of market microstructure noise complicates the analysis of high frequency *** survey introduces several robust methods of volatility estimation and jump tests in the presence of market microstructure ***,some applications of jump tests in asset pricing are discussed in this article.

关键词： high frequency data quadratic variation(QV) realized variance(RV) power variation(PV) bipower variation jump tests market microstructure noise asset pricing

Noni juice is not hepatotoxic

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World journal of Gastroenterology 2006年第22期12卷 3616-3619页

作者： Brett j West C jarakae jensen johannes Westendorf Research and Development Department Tahitian Noni International American ForkUtahUnited States University Medical School of Hamburg Department of Toxicology HamburgGennany

Noni juice （Morinda citrifolia） has been approved for use as a safe food within the European Union, following a review of safety. Since approval, three cases of acute hepatitis in Austrian noni juice consumers have been published, where a causal link is suggested between the liver dysfunction and ingestion of anthraquinones from the plant. Measurements of liver function in a human clinical safety study of TAHITIAN NONI juice, as well as subacute and subchronic animal toxicity tests revealed no evidence of adverse liver effects at doses many times higher than those reported in the case studies. Additionally, M. citrifolia anthraquinones occur in the fruit in quantities too small to be of any toxicological significance. Further, these do not have chemical structures capable of being reduced to reactive anthrone radicals, which were implicated in previous cases of herbal hepototoxicity. the available data reveals no evidence of liver toxicity.

关键词： Noni juice Morinda citrifolia Novel food Human clinical safety study