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Communications in Computational physics 2009年第2期5卷 484-497页

作者： john p.Boyd Jun Rong Ong Department of Atmospheric Oceanic and Space ScienceUniversity of Michigan2455 Hayward AvenueAnn ArborMI 48109USA Department of Electrical Engineering and Computer Science University of Michigan2455 Hayward AvenueAnn ArborMI 48109USA

Approximating a function from its values f(x_(i))at a set of evenly spaced points x_(i)through(N+1)-point polynomial interpolation often fails because of divergence near the endpoints,the“Runge phenomenon”.Here we briefly describe seven strategies,each employing a single polynomial over the entire interval,to wholly or partially defeat the Runge phenomenon such that the error decreases exponentially fast with *** is successful in obtaining high accuracy for Runge’s original ***,each of these single-interval strategies also has liabilities including,depending on the method,various permutations of inefficiency,ill-conditioning and a lack of *** so,the Fourier Extension and Gaussian RBF methods are worthy of further development.

关键词： Interpolation Runge phenomenon Fourier extension radial basis functions

Sulfonation of Hydroxymethylated Lignin and Its Application

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Journal of Bioresources and Bioproducts 2019年第2期4卷 80-88页

作者： Weijue GAOD john p.W.INWOODD pedram FATEHI Department of Chemical Engineering and Green processes Research Centre Lakehead University955 Oliver RoadThunder Bay P7B5E1Canada

To valorize kraft lignin,hydroxymethylation and sulfonation were applied on this under-utilized,but vastly available,*** hydroxymethylation pretreatment was conducted as means to improve the reactivity of *** sulfonation of hydroxymethylated kraft lignin was investigated by sulfuric acid and sodium sulfite treatments under various *** modified lignin samples were characterized for their charge density,solubility,elemental components,and molecular *** results showed that the hydroxymethylation facilitated the sulfonation by sodium sulfite,yielding a product(SSH-lignin)with the charge density of-1.2 meq/g and water solubility of 10 g/L under the conditions of Ns_(2)SO_(3)/lignin molar ratio of 0.49 mol/mol,95℃and 3 *** the other hand,hydroxymethylation hindered the sulfonation of lignin by sulfuric acid,yielding a product(SAH-lignin)with the charge density of–0.46 meq/g and solubility of 0.9 g/L under the conditions of H_(2)SO_(4)/lignin molar ratio of 14.8 mol/mol,80℃and 1 *** SSH-lignin had a high adsorption on kaolinite(17 mg/g)at a lignin concentration of 40 g/*** sulfonated lignins were also found to be effective coagulant for the cationic dye ethyl violet.

关键词： kraft lignin hydroxymethylation sulfonation adsorption dye removal

Lipid metabolism is associated with temperament,corticosteroid,and hematological measures in infant rhesus monkeys(Macaca mulatta)

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Zoological Research 2020年第6期41卷 709-714页

作者： john p.Capitanio Frederik Dethloff Christoph W.Turck Department of psychology University of CaliforniaDavis 95616USA California National primate Research Center University of CaliforniaDavis 95616USA Max planck Institute of psychiatry Munich 80804Germany

DEAR EDITOR,Individuals can differ in how their behavioral and physiological systems are *** fact that these individual differences persist across life suggests they are supported by physical structures that may ***,we explored three datasets associated with health and behavioral outcomes,which were obtained from infant rhesus monkeys during standardized assessment of biobehavioral *** in biobehavioral measures was related to variation in molecular pathways,as assessed by metabolomics.

关键词： infant metabolism Lipid

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Calculation and interpretation of classical turning surfaces in solids

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npj Computational Materials 2021年第1期7卷 229-238页

作者： Aaron D.Kaplan Stewart J.Clark Kieron Burke john p.perdew Department of physics Temple UniversityPhiladelphiaPA 19122USA Centre for Materials physics Durham UniversityDurham DH13LEUK Departments of Chemistry and physics University of CaliforniaIrvineCA 92697USA Departments of physics and Chemistry Temple UniversityPhiladelphiaPA 19122USA

Classical turning surfaces of Kohn–Sham potentials separate classically allowed regions(CARs)from classically forbidden regions(CFRs).They are useful for understanding many chemical properties of molecules but need not exist in solids,where the density never decays to *** equilibrium geometries,we find that CFRs are absent in perfect metals,rare in covalent semiconductors at equilibrium,but common in ionic and molecular *** all materials,CFRs appear or grow as the internuclear distances are uniformly *** can also appear at a monovacancy in a *** with several approximate density functionals and codes confirm these behaviors.A classical picture of conduction suggests that CARs should be connected in metals,and disconnected in wide-gap insulators,and is confirmed in the limits of extreme compression and ***,many semiconductors have no CFR at equilibrium,a key finding for density functional ***,a strong correlation with insulating behavior can still be ***,equilibrium bond lengths for all cases can be estimated from the bond type and the sum of the classical turning radii of the free atoms or ions.

关键词： turning solids expanded

Efficacy of infliximab in acute severe ulcerative colitis:A single-centre experience

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World Journal of Gastroenterology 2013年第7期19卷 1091-1097页

作者： Stephen J Halpin p john Hamlin Daniel p Gree Lisa Warren Alexander C Ford Leeds Gastroenterology Institute St.James's University HospitalLeedsWest Yorkshire LS9 7TFUnited Kingdom Leeds Gastroenterology Institute St.James's University HospitalLeedsWest Yorkshire LS9 7TFUnited Kingdom r Leeds Institute of Molecular Medicine University of LeedsLeedsWest Yorkshire LS9 7TFUnited Kingdom

AIM:To suggest infliximab(IFX) is effective for acute severe ulcerative colitis,from real-life clinical ***:All patients receiving IFX for the treatment of acute severe ulcerative colitis in a single centre were *** were extracted from clinical records in order to assess response to IFX *** primary endpoint was colectomy-free survival,and secondary outcomes included glucocorticosteroid-free remission and safety,which was evaluated by recording deaths and adverse *** and clinical characteristics of those who underwent colectomy and those who were colectomy-free,both at discharge from their index admission,and during follow-up after an initial response to IFX were ***:Forty-four patients(16 females,mean age 36 years) received IFX between May 2006 and January 2012 for acute severe ulcerative *** median duration of follow-up post-first infusion was 396 d(interquartile range = 173-828 d).There were 21(47.7%) patients with p,10(22.7%) with 1 years to 2 years of follow-up,and 13(29.5%) with > 2 years of follow-up post-first infusion of ***,35(79.5%) responded to IFX,avoiding colectomy during their index admission,29(65.9%) were colectomyfree at last point of follow-up(median follow-up 396 d),and 25(56.8%) were in glucocorticosteroid-free remission at end of *** was one death from post-operative sepsis,20 d after a single IFX *** rates were generally lower among those "bridging" to *** 18 patients "bridged" to thiopurine therapy,17(94.4%) were colectomyfree,and 15(83.3%) were in glucocorticosteroid-free remission at study *** predictors of response were ***:IFX is effective for acute severe ulcerative colitis in real-life clinical ***-thirds of patients avoided colectomy,and more than 50% were in glucocorticosteroid-free remission.

关键词： Ulcerative colitis Severe Azathioprine Infliximab Remission

Determination of water environment standards based on water quality criteria in China:Limitations and feasibilities

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Journal of Environmental Sciences 2017年第7期29卷 127-136页

作者： Tieyu Wang Yunqiao Zhou Cencen Bi Yonglong Lu Guizhen He john p.Giesy State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China Toxicology Centre and Department of Veterinary Biomedical Sciences University of SaskatchewanSaskatoonSaskatchewanCanada

There is a need to formulate water environment standards（WESs） from the current water quality criteria（WQC） in *** this end,we briefly summarize typical mechanisms applied in several countries with longer histories of developing WESs,and three limitations to formulating WESs in China were *** analyzing the feasibility factors including economic development,scientific support capability and environmental policies,we realized that China is still not ready for a complete change from its current nation-wide unified WES system to a local-standard-based ***,we proposed a framework for transformation from WQC to WESs in *** framework consists of three parts,including responsibilities,processes and *** responsibilities include research authorization,development of guidelines,and collection of information,at both national and local levels;the processes include four steps and an impact factor system to establish water quality standards;and the policies include seven specific proposals.

关键词： Water quality Environmental criteria Standards Regulations

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Investigation of Terminal Group Effect on Electron Transport Through Open Molecular Structures

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Communications in Theoretical physics 2013年第5期59卷 649-654页

作者： C. preferencial Kala p. Aruna priya D. john Thiruvadigal Department of physics and Nano Technology Center for Materials Science and NanodevicesSRM University Department of Electronics and Communication Engineering Center for Materials Science and NanodevicesSRM University

The effect of terminal groups on the electron transport through metal-molecule-metal system has been investigated using nonequilibrium Green’s function (NEGF) formalism combined with extended Huckel theory (EHT). Au-molecule-Au junctions are constructed with borazine and BCN unit structure as core molecule and sulphur (S), oxygen (O), selenium (Se) and cyano-group (CN) as terminal groups. The electron transport characteristics of the borazine and BCN molecular systems are analyzed through the transmission spectra and the current-voltage curve. The results demonstrate that the terminal groups modifying the transport behaviors of these systems in a controlled way. Our result shows that, selenium is the best linker to couple borazine to Au electrode and oxygen is the best one to couple BCN to Au electrode. Furthermore, the results of borazine systems are compared with that of BCN molecular systems and are discussed. Simulation results show that the conductance through BCN molecular systems is four times larger than the borazine molecular systems. Negative differential resistance behavior is observed with borazine-CN system and the saturation feature appears in BCN systems.

关键词： molecular electronics extended Huckel theory (EHT) nonequilibrium Green’s function (NEGF) quantum transport

Artificial nesting habitats as a conservation strategy for turtle populations experiencing global change

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Integrative Zoology 2013年第2期8卷 209-221页

作者： john p.WNEK Walter F.BIEN Harold W.AVERY Department of Biology Drexel UniversityPhiladelphiaPennsylvaniaUSA

Diamondback terrapins(Malaclemys terrapin)inhabit estuaries in eastern USA and may tolerate salinity of seawater for short *** North American estuaries are adversely affected by anthropogenic impacts,such as pollution,dredging and invasion by non-native *** nesting areas have been altered or destroyed,causing terrapins to nest on roadsides and artificial islands made of dredged substrate from bottom *** by non-native plants may suppress development and reduce survival of *** Barnegat Bay,New Jersey,USA,there is a mosaic of natural and degraded terrapin nesting *** investigated the effects of dredge soil and shade on the hatching success of diamondback terrapins to determine whether nesting habitat could be increased by using dredged bottom *** year 1,unshaded nests in natural loamy-sand had the highest hatching success(55.2%),while nests in dredge soil produced no *** year 2,nests in unshaded loamy-sand had a hatching success of 85.3%,whereas those in dredge soil,aged 1 year,had a hatching success of 59.4%.Dredge soil improved as an incubation substrate after aging 1 year by the washout of *** temperatures were generally cool and produced mostly male *** dredge soil may provide suitable nesting substrates for diamondback terrapins if used after one year,and may be particularly beneficial if used for constructing islands that provide new nesting sites with reduced access of mammalian predators.

关键词： dredge estuarine turtles hatching success Malaclemys terrapin nesting ecology nest temperature nest substrate shade

predictive modelling of ferroelectric tunnel junctions

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npj Computational Materials 2016年第1期2卷 150-162页

作者： Julian p Velev john D Burton Mikhail Ye Zhuravlev Evgeny Y Tsymbal Department of physics and Astronomy University of NebraskaLincolnNEUSA Department of physics and Astronomy University of Puerto RicoSan JuanPuerto RicoUSA Nebraska Center for Materials and Nanoscience University of NebraskaLincolnNEUSA Kurnakov Institute for General and Inorganic Chemistry Russian Academy of SciencesMoscowRussia Faculty of Liberal Arts and Sciences St Petersburg State UniversitySt PetersburgRussia

Ferroelectric tunnel junctions combine the phenomena of quantum-mechanical tunnelling and switchable spontaneous polarisation of a nanometre-thick ferroelectric film into novel device *** the ferroelectric barrier polarisation direction produces a sizable change in resistance of the junction—a phenomenon known as the tunnelling electroresistance *** a fundamental perspective,ferroelectric tunnel junctions and their version with ferromagnetic electrodes,i.e.,multiferroic tunnel junctions,are testbeds for studying the underlying mechanisms of tunnelling electroresistance as well as the interplay between electric and magnetic degrees of freedom and their effect on *** a practical perspective,ferroelectric tunnel junctions hold promise for disruptive device *** a very short time,they have traversed the path from basic model predictions to prototypes for novel non-volatile ferroelectric random access memories with non-destructive *** remarkable progress is to a large extent driven by a productive cycle of predictive modelling and innovative experimental *** this review article,we outline the development of the ferroelectric tunnel junction concept and the role of theoretical modelling in guiding experimental *** discuss a wide range of physical phenomena that control the functional properties of ferroelectric tunnel junctions and summarise the state-of-the-art achievements in the field.

关键词： ferroelectric tunnel resistance

New Clues that May Link Osteoporosis to the Circulating Lipid profile

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Bone Research 2013年第3期1卷 260-266页

作者： Catalina poiana Valentin Radoi Mara Carsote john p. Bilezikian "C. I. parhon" National Institute of Endocrinology Bucharest Bucharest Romania University of Medicine and pharmacy"Carol Davila" Bucharest Bucharest Romania College of physicians and Surgeons Columbia UniversityNew York NY USA

Bone Mineral Density （BMD） is a gold standard for the diagnosis of osteoporosis and is also important in the assessment of fracture risk. Other risk factors have been identified that together make up fracture risk assessment tools such as FRAX. Another potential factor, circulating lipids, has been suggested because of reports linking statins to fracture risk reduction. We analyzed the lipid profile in a cohort of women diagnosed with postmenopausal osteoporosis based on bone density determination： 610 women with osteo- porosis （mean lumbar spine T-score -3.16±0.81, mean yrs. since menopause 15.79±8.9） were grouped according to age at evaluation （〈 50 years, 51-60 years, 61-70 years, 〉 70 years）, the presence/absence of a history of a fragility fracture, statin and/or antiresorptive drug use. There was no correlation between BMD and Body Mass Index （BMI： p〉0.05, r2〈0.02）. However, when BMD was correlated with both BMI and the lipid profile （Triglycerides, Cholesterol, LDLc, HDLc）, significant correlations were found in 5 cohorts： 51-60 years with fractures （n=61, r2=0.14, p〈0.01）, 61-70 years （n=201, r2=0.09, p〈0.01） with fractures （n=88, r2=0.14, p〈0.01） or without fractures （n=113, r2=0.24, p=0.02） and over 70 years （n=247, r2=0.11, p〈0.01）.

关键词： osteoporosis bone mineral density lipid cholesterol triglycerides HDL-cholesterol

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