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HEAVY-QUARK AND SOFT-COLLINEAR EFFECTIVE THEORY

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Chinese Physics C 2016年第10期40卷 303-309页

作者： C.W. bauer m. Neubert LBNL U. mainz

17.1. Effective Field Theories Quantum field theories provide the most precise computational tools for describing physics at the highest energies. One of their characteristic features is that they almost inevitably involve multiple length scales. When trying to determine the value of an observable, quantum field theory demands that all possible virtual states and hence all particles be included in the calculation. Since these particles have widely different masses, the final prediction is sensitive to many scales. This fact represents a formidable challenge from a practical point of view. No realistic quantum field theories can be solved exactly, so that one needs to resort to approximation schemes; these, however, are typically most straightforward when only a single scale is involved at a time.

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Setting kinetics and mechanical properties of flax fibre reinforced glass ionomer restorative materials

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The Journal of Biomedical Research 2017年第3期31卷 264-272页

作者： Ensanya Ali Abou Neel anne m.Young Division of Biomaterials Conservative Dental Sciences DepartmentKing Abdualziz University Biomaterials Department Faculty of DentistryTanta University Division of Biomaterials and Tissue Engineering UCL Eastman Dental Institute

Regardless of the excellent properties of glass ionomer cements,their poor mechanical properties limit their applications to non-load bearing *** study aimed to investigate the effect of incorporated short,chopped and randomly distributed flax fibers（0,0.5,1,2.5,5 and 25 wt%） on setting reaction kinetics,and mechanical and morphological properties of glass ionomer *** of flax fibers did not significantly affect the setting reaction *** to their content,flax fibers increased the compressive（from 148 to 250 mPa） and flexure strength（from 20 to 42 mPa）.They also changed the brittle behavior of glass ionomer cements to a plastic *** significantly reduced the compressive（from 3 to 1.3 GPa） and flexure modulus（from 19 to 14 GPa）.Accordingly,flax fiber-modified glass ionomer cements could be potentially used in high-stress bearing areas.

关键词： setting kinetics flax fibre glass ionomer cements

Corrosion behavior of Fe–Cr–Ni based alloys exposed to molten mgCl_(2)–KCl–NaCl salt with over-added mg corrosion inhibitor

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Frontiers of Chemical Science and Engineering 2023年第10期17卷 1608-1619页

作者： Rui Yu Qing Gong Hao Shi Yan Chai Alexander Bonk Alfons Weisenburger Dihua Wang Georg müller Thomas bauer Wenjin Ding Institute for Pulsed Power and microwave Technology Karlsruhe Institute of Technology(KIT)76344 Eggenstein-LeopoldshafenGermany School of Resources and Environmental Science Wuhan University(WHU)Wuhan 430072China Institute of Engineering Thermodynamics German Aerospace Center(DLR)70569 StuttgartGermany Institute of Engineering Thermodynamics German Aerospace Center(DLR)70569 CologneGermany

mgCl_(2)–NaCl–KCl salts mixture shows great potential as a high-temperature(>700°C)thermal energy storage material in next-generation concentrated solar power *** mg into molten mgCl_(2)–NaCl–KCl salt as a corrosion inhibitor is one of the most effective and cost-effective methods to mitigate the molten salt corrosion of commercial Fe–Cr–Ni ***,it is found in this work that both stainless steel 310 and Incoloy 800H samples were severely corroded after 500 h immersion test at 700°C when the alloy samples directly contacted with the over-added mg in the liquid *** corrosion attack is different from the classical impurity-driven corrosion in molten chloride salts found in previous *** analysis indicates that Ni preferentially leaches out of alloy matrix due to the tendency to form mgNi_(2)/mg_(2)Ni *** Ni-depletion leads to the formation of a porous corrosion layer on both alloys,with the thickness around 204μm(stainless steel 310)and 1300μm(Incoloy 800H),*** results suggest that direct contact of liquid mg with Ni-containing alloys should be avoided during using mg as a corrosion inhibitor for mgCl_(2)–NaCl–KCl or other chlorides for high temperature heat storage and transfer.

关键词： concentrated solar power(CSP) mg corrosion inhibitor mg-Ni intermetallic salt purification thermal energy storage(TES)

Improved source assessment of Si,Al and related mineral components to Pm_(10) based on a daily sampling procedure

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Journal of Environmental Sciences 2010年第4期22卷 582-588页

作者： Ge Peng Hans Puxbaum Heidi bauer Nicole Jankowski Yao Shi Chemical Engineering College Ningbo University of Technology Ningbo 315016 China. Institute for Chemical Technologies and Analytics Vienna University of Technology Vienna 1060 Austria College of Environmental and Resource Sciences Zhejiang University Hangzhou 310027 China

Samples obtained from an industrialized valley in the East Alpine region were collected daily for a half year and analyzed using X-ray fluorescence to examine the elements Si, Al, Fe, Ca, mg, Na, K, Zn, P, S and Cl. Some factors affecting the changes of these elements were considered, including time, elemental correlations, weekday, weekend and seasonal changes. Diagnostic analysis provided an insight into a decoupling behavior that occursin siliceous and carbonates minerals. A decrease in Si and Al and an increase in carbonates, Na, K, Zn and P were observed during the cold season. However, a consistently high correlation of Si and Al was observed in all seasons. It was established that such high levels originated from street surface abrasion. The increase in variability and absolute levels of carbonates during the cold season was demonstrated by adding carbonates to the street surface as gritting material to increase the grip on snowy surfaces. A marked increase in Na and Cl was observed in winter which may have been caused by thaw salt that is widely used in winter in Austria. This was associated with a significant increase in K, Zn, and P in the cold season that was the result of domestic space heating with wood. Pm10 levels in December were 12 μ/m^3 and were higher than levels detected in July. It was established that such high levels originated from mineral oxides, wood smoke, and inorganic ionic material（s）.

关键词： particulate matter Pm10 mineral aerosol silicates carbonates street dust wood combustion thaw salt

Gradients in predation risk in a tropical river system

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Current Zoology 2018年第2期64卷 213-221页

作者： Amy E. DEACON Faith A. m. JONES anne E. mAGURRAN Department of Life Sciences The University of the West Indies St Augustine Trinidad and Tobago School of Biology University of St Andrews Fife KY16 9TH Scotland UK

The importance of predation risk as a key driver of evolutionary change is exemplified by the Northern Range in Trinidad, where research on guppies living in multiple parallel streams has pro- vided invaluable insights into the process of evolution by natural selection. Although Trinidadian guppies are now a textbook example of evolution in action, studies have generally categorized predation as a dichotomous variable, representing high or low risk. Yet, ecologists appreciate that community structure and the attendant predation risk vary substantially over space and time. Here, we use data from a longitudinal study of fish assemblages at 16 different sites in the Northern Range to quantify temporal and spatial variation in predation risk. Specifically we ask： 1） Is there evidence for a gradient in predation risk？ 2） Does the ranking of sites （by risk） change with the defi- nition of the predator community （in terms of species composition and abundance currency）, and 3） Are site rankings consistent over time？ We find compelling evidence that sites lie along a contin- uum of risk. However, site rankings along this gradient depend on how predation is quantified in terms of the species considered to be predators and the abundance currency is used. Nonetheless, for a given categorization and currency, rankings are relatively consistent over time. Our study sug- gests that consideration of predation gradients will lead to a more nuanced understanding of the role of predation risk in behavioral and evolutionary ecology. It also emphasizes the need to justify and report the definition of predation risk being used.

关键词： abundance currency gradients Poecilia reticulata predation risk Trinidad Trinidadian guppy.

Detecting accidental punctures and lacerations during cholecystectomy in large datasets: Two methods of analysis

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Hepatobiliary & Pancreatic Diseases International 2018年第5期17卷 430-436页

作者： Artem Shmelev anne m Sill Gopal C Kowdley Juan A Sanchez Steven C Cunningham Department of Surgery Saint Agnes Hospital and Cancer Center

Background: After the Institute of medicine(IOm) report To Err Is Human highlighted the impact of medical errors, the Agency for Healthcare Research and Quality(AHRQ) developed Patient-Safety Indicators(PSI) to improve quality by identifying potential inpatient safety problems. PSI-15 was created to study accidental punctures and lacerations(APL), but PSI-15 may underestimate APLs in populations of patients. This study compares PSI-15 with a more inclusive approach using a novel composite of secondary diagnostic and procedural codes. methods: We used Nationwide Inpatient Sample(NIS) data(20 0 0–2012) from AHRQ’s Healthcare Cost and Utilization Project(H-CUP). We analyzed PSI-15-positive and-negative cholecystectomies. Cross tabulations identified codes that were significantly more frequent among PSI-15-positive cases; these secondary diagnostic and procedural codes were selected as candidate members of a composite marker(Cm) of APL. We chose cholecystectomy patients for study because this is one of the most common general operations, and the large size of NIS allows for meaningful analysis of infrequent occurrences such as APL rates. Results: Cm identified 1.13 times more APLs than did PSI-15. Patients with Cm-detected APLs were significantly older and had worse mortality, comorbidities, lengths of stay, and charges than those detected with PSI-15. Further comparison of these two approaches revealed that time-series analysis for both APL markers revealed parallel trends, with inflections in 2007, and lowest APL rates in July. Conclusions: Although Cm may yield more false positives, it appears more inclusive, identifying more clinically significant APLs, than PSI-15. Both measures presented similar trends over time, arguing against inflation in PSI-15 reporting. While arguably less specific, Cm may increase sensitivity for detecting APL events during cholecystectomies. These results may inform the interpretation of other large population studies of APLs following abd

关键词： Cholecystectomy Patient safety Accidental lacerations AHRQ PSI-15

Assessing disease activity using the pediatric Crohn’s disease activity index:Can we use subjective or objective parameters alone?

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World Journal of Gastroenterology 2021年第30期27卷 5100-5111页

作者： Amy Grant Trudy Lerer anne m Griffiths JS Hyams Anthony Otley Division of Pediatrics IWK HealthHalifaxNS B3K6R8Canada Division of Research Connecticut Children's Medical CenterHartfordCT 06106United States Division of Gastroenterology Hepatology and Nutrition The Hospital for Sick ChildrenTorontoON M5G1X8Canada Division of Gastroenterology Connecticut Children's Medical CenterHartfordCT 06106United States Division of Pediatrics Dalhousie UniversityHalifaxNS B3H4C3Canada

BACKGROUND The pediatric Crohn’s disease activity index(PCDAI)is used as a standard tool to assess disease activity in clinical trials for pediatric Crohn’s *** To examine which items on the PCDAI drive assessment of disease activity,and how subgroups of subjective and objective items reflect change in disease state over *** Selective raw data from three prospectively collected datasets were combined,including 703 children with full PCDAI data at baseline,at 3-mo(Q1,n=670),and 1-year(Q4,n=474).Change in individual PCDAI scores from baseline to Q1 and to Q4 were examined using the non-weighted *** Abdominal pain,well-being,weight,and stooling had the highest change scores over *** indicators including albumin,abdominal exam,and height velocity *** scores for well-being and abdominal exam did not explain significant variance at Q1 but were significant predictors at Q4(Pms predicted less variance(18%and 22%)on total PCDAI scores at Q1 and Q4 compared to the full PCDAI,or a composite scale(both 32%)containing significant *** Although subjective items on the PCDAI change the most over time,the full PCDAI or a smaller composite of items including a combination of subjective and objective components classifies disease activity better than a subgroup of either subjective or objective items *** on subjective or objective items as stand-alone proxies for disease activity measurement could result in misclassification of disease state.

关键词： Crohn’s disease Pediatric Crohn’s disease activity index Patient reported outcome measurement Disease activity Clinical trials Pediatric

matrix Roots and Embedding Conditions for Three-State Discrete-Time markov Chains with Complex Eigenvalues

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Communications in mathematics and Statistics 2022年第3期10卷 435-450页

作者： marie-anne Guerry Department of Business Technology and Operations Vrije Universiteit Brussel(VUB)Pleinlaan 21050 BrusselsBelgium

The present paper examines matrix root properties and embedding conditions for discrete-time markov chains with three states and a transition matrix having complex *** as well as sufficient conditions for the existence of an m-th stochastic root of the transition matrix are *** roots are expressed in analytical form based on the spectral decomposition of the transition matrix,and properties of these matrix roots are proved.

关键词： markov chain Embedding problem matrix root Complex eigenvalues

Investigation of dry sliding wear properties of multi-directional forged mg-Zn alloys

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Journal of magnesium and Alloys 2019年第3期7卷 444-455页

作者： S.Ramesh Gajanan anne H.Shivananda Nayaka Sandeep Sahu m.R.Ramesh Department of mechanical Engineering National Institute of Technology KarnatakaSurathkal 575025India Department of mechanical Engineering Shri Madhwa Vadiraja Institute of Technology and ManagementUdupiKarnataka 574115India Department of materials Science and Engineering Indian Institute of Technology KanpurKanpur 208016India

Effect of multi-directional forging(mDF)on wear properties of mg-Zn alloys(with 2,4,and 6wt%Zn)is *** sliding wear test was performed using pin on disk machine on mDF processed and homogenized *** behavior of samples was analyzed at loads of ION and 20 N,with sliding distances of 2000m and 4000m,at a sliding velocity of 3m/*** of worn samples were observed under scanning electron microscopy(SEm),energy dispersive spectroscopy(EDS),and x-ray diffraction(XRD)and the results were *** properties were evaluated using microhardness *** 5 passes of mDF,the average grain size was found to be 30±4p m,22±3 pm,and 18±3 pm,in mg-2%Zn,mg-4%Zn,and mg-6%Zn alloys,respectively,with significant improvement in hardness in all *** resistance was improved after mDF processing,as well as,with increment in Zn content in mg ***,it decreased when the load and the sliding distance *** surface exhibited ploughing,delamination,plastic deformation,and wear debris along sliding direction,and abrasive wear was found to be the main mechanism.

关键词： multi-directional forging mg-Zn alloy microhardness Wear Coefficient of friction