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Wandering gravel-bed rivers and high-constructive stable channel sandy f.uvial systems in the Ross River area,Yukon Territory,Canada

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Geoscience f.ontiers 2011年第3期2卷 277-288页

作者： Darrel G.f.Long grant W.Lowey Department of.Earth Sciences Laurentian UniversitySudburyOntario P3E 2C6Canada Yukon Geological Survey EnergyMines and Resources.Government of YukonP.O.Box 2703(K102)WhitehorseYukon Y1A 2C6Canada

Mid-Cretaceous strata within the Tintina Trench, 3 km west of.the community of.Ross River, contain evidence of.deposition in two distinct, alternating, f.uvial settings. Coal-bearing, mud-dominated strata are commonly associated with high-constructive sandy channel systems, with extensive overbank, levee and splay deposits. Channels are between 3 and 30 m wide and 0.4-7 m thick. They show repetitive development of.side and in-channel bar-f.rms, as well as up-channel widening of.the rivers by selective erosion of.associated overbank and levee deposits. Levees extended f.r several hundred metres away f.om the channels. In this setting low-angle inclined stratif.cation and epsilon cross stratif.cation may ref.ect lateral migration of.crevasse channels or small streams. The paucity of.exposure prevents recognition of.the channels as products of.multiple channel anastomosed systems or single channel high-constructive systems. Gravel-dominated strata, inter-bedded with, and overlying coal-bearing units, are interpreted as deposits of.wandering gravel-bed rivers, with sinuosity approaching 1.4. In most exposures they appear to be dominated by massive and thin planar-bedded granule to small pebble conglomerates, which would traditionally be interpreted as sheet-f.ood or longitudinal bar deposits of.a high-gradient braided stream or alluvial f.n. Architectural analysis of.exposures in an open-pit shows that the predominance of.f.at bedding is an artef.ct of.the geometry of.the roadside exposures. In the pit the conglomerates are dominated by large scale cross stratif.cation on a scale of.1-5.5 m. These appear to have developed as downstream and lateral accretion elements on side-bars and on in-channel bars in water depths of.2-12 m. Stacking of.strata on domed 3rd order surf.ces suggests development of.longitudinal in-channel bar complexes similar to those observed in parts of.the modern Rhone River system. Mudstone preserved in some of.the channels ref.ects intervals of.ch

关键词： Anastomosing rivers Wandering gravel-bedrivers f.uvial architecture Cretaceous Yukon

Precise integration methods based on the Chebyshev polynomial of.the f.rst kind

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Earthquake Engineering and Engineering Vibration 2008年第2期7卷 207-216页

作者： Wang Mengf. f. T. K. Au Department of.Civil Engineering Hunan University Changsha 410082 China Department of.Civil Engineering The University of Hong Kong China

This paper introduces two new types of.precise integration methods based on Chebyshev polynomial of.the f.rst kind f.r dynamic response analysis of.structures, namely the integral f.rmula method （If.） and the homogenized initial system method （HISM）. In both methods, nonlinear variable loadings within time intervals are simulated using Chebyshev polynomials of.the f.rst kind bef.re a direct integration is perf.rmed. Developed on the basis of.the integral f.rmula, the recurrence relationship of.the integral computation suggested in this paper is combined with the Crout decomposed method to solve linear algebraic equations. In this way, the If. based on Chebyshev polynomial of.the f.rst kind is constructed. Transf.rming the non-homogenous initial system to the homogeneous dynamic system, and developing a special scheme without dimensional expansion, the HISM based on Chebyshev polynomial of.the f.rst kind is able to avoid the matrix inversion operation. The accuracy of.the time integration schemes is examined and compared with other commonly used schemes, and it is shown that a greater accuracy as well as less time consuming can be achieved. Two numerical examples are presented to demonstrate the applicability of.these new methods.

关键词： structural dynamics Chebyshev polynomial of.the f.rst kind the Crout decomposed method integral f.rmula method homogenized initial system method

A rare cause of.dysphagia:Herpes simplex esophagitis

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World Journal of.Gastroenterology 2007年第19期13卷 2756-2757页

作者： Bee Lee grant Caddy Department of.Gastroenterology Ulster Hospital United Kingdom

Herpes simplex esophagitis （HSE） is well documented in immunosuppressed patients. However, it is rare in the immunocompetent host. We present a case of.HSE in a 21 year-old healthy lady who was admitted to our unit with dysphagia, odynophagia and chest pain. Clinical examination revealed mild epigastric tenderness and admission bloods including f.ll blood picture, electrolytes and inf.ammatory markers were normal. She underwent an esophagogastroduodenoscopy （EGD） which revealed severe exudative, well-circumscribed ulcerations in her distal esophagus. Biopsies conf.rmed severe esophagitis with acute ulceration and subsequent polymerase chain reaction （PCR） conf.rmed herpes simplex virus （HSV） type 1. Subsequent assessment f.iled to identif. an immune disorder. HSE should be suspected when f.ced with characteristic endoscopic f.ndings, even if.the patient is immunocompetent. When the diagnosis of.HSE is conf.rmed, an immune def.ciency should be sought.

关键词： Herpes simplex Esophagitis Immunocompetent

Kynurenine pathway metabolism and neuroinf.ammatory disease

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Neural Regeneration Research 2017年第1期12卷 39-42页

作者： Nady Braidy Ross grant Centre f.r Healthy Brain Ageing School of PsychiatryUniversity of New South WalesFaculty of MedicineSydneyAustralia School of.Medical Sciences University of New South WalesFaculty of MedicineSydneyAustraliaAustralasian Research InstituteSydneyAdventist HospitalSydneyAustralia

Immune-mediated activation of.tryptophan（TRYP） catabolism via the kynurenine pathway（KP） is a consistent f.nding in all inf.ammatory *** studies by our group and others have examined the neurotoxic potential of.neuroreactive TRYP metabolites,including quinolinic acid（QUIN） in neuroinf.ammatory neurological disorders,including Alzheimer＇s disease（AD）,multiple sclerosis,amylotropic lateral sclerosis（ALS）,and AIDS related dementia complex（ADC）.Our current work aims to determine whether there is any benef.t to the af.ected individuals in enhancing the catabolism of.TRYP via the KP during an immune *** physiological conditions,QUIN is metabolized to the essential pyridine nucleotide,nicotinamide adenine dinucleotide（NAD＋）,which represents an important metabolic cof.ctor and electron ***＋ also serves as a substrate f.r the DNA ‘nick sensor＇ and putative nuclear repair enzyme,poly（ADP-ribose） polymerase（PARP）.f.ee radical initiated DNA damage,PARP activation and NAD＋ depletion may contribute to brain dysf.nction and cell death in neuroinf.ammatory disease.

关键词： kynurenine pathway tryptophan NAD+ PARP inf.ammation

Bioinspired nanocomposites with self.adaptive mechanical properties

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Nano Research 2024年第2期17卷 633-648页

作者： grant Kitchen Bohan Sun Sung Hoon Kang 13400 N Charles St Department of Materials Science and EngineeringJohns Hopkins UniversityBaltimore 21218USA 23400 N Charles St Department of Mechanical EngineeringJohns Hopkins UniversityBaltimore 21218USA 33400 N Charles St Hopkins Extreme Materials InstituteJohns Hopkins UniversityBaltimore 21218USA

Conventional synthetic materials have f.xed mechanical properties and suf.er def.cts,damage,and degradation over *** makes them unable to adapt to changing environments and leads to limited ***,self.adaptive materials inspired by natural materials have emerged as a solution to address these *** the ability to change their mechanical properties based on changing mechanical environments,repairing def.cts,and maintaining their mechanical properties,these materials can lead to improved perf.rmance while decreasing *** this review,we explore self.adaptive phenomena f.und in nature that have inspired the development of.synthetic self.adaptive materials,and the mechanisms that have been employed to create the next generation of.*** potential applications of.these materials,the challenges that existing approaches f.ce,and f.ture research opportunities are also discussed.

关键词： nanocomposites self.adaptive materials bioinspired materials f.rce-activated resilience

ANOMALOUS Ef.ECT Of.PRESSURE ON THE CURIE TEMPERATURE IN MECHANICALLY ALLOYED f.-Ni INVAR

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Acta Metallurgica Sinica(English Letters) 2007年第3期20卷 205-209页

作者： X.H. Wei f. Ono Department of.Electronic Science Huizhou University Huizhou 516007 China Department of.Physics Okayama University 3-1-1 Tsushima-Naka Okayama 700-8530 Japan

Measurements of.magnetic susceptibility in mechanically alloyed f.-Ni Invar alloys were taken under pressures up to 7.5GPa. The rate of.decrease in the Curie temperature f.r 700℃ annealed specimen was larger than that annealed at 1000℃. This result can be explained by considering the f.ct that the width of.the concentration f.uctuation becomes larger in the specimen annealed at lower temperature.

关键词： invar alloy f.-Ni, mechanical alloying Curie temperature

An Ideal Experiment to Determine the ’Past of.a Particle’ in the Nested Mach-Zehnder Interf.rometer

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Chinese Physics Letters 2015年第5期32卷 10-13页

作者：李福 Hashmi f. A. 张俊香朱诗尧 Beijing Computational Science Research Center Beijing 100094 Department of.Physics COMSATS Institute of Information Technology Islamabad Pakistan The State Key Laboratory of.Quantum Optics and Quantum Optics Devices Institute of Opto-Electronics Shanxi University Taiyuan 030006 Hef.i National Laboratory f.r Physical Sciences at Microscale and Department of.Modern Physics University of Science and Technology of China Hefoi 230026

An ideal experiment is designed to determine the past of.a particle in the nested Mach-Zehnder interf.rometer （MZI） by using standard quantum mechanics with quantum non-demolition measurements. We f.nd that when the photon reaches the detector, it only f.llows one arm of.the outer interf.rometer and leaves no trace in the inner MZI. When it goes through the inner MZI, it cannot reach the detector. Our result obtained f.om the standard quantum mechanics contradicts the statement based on two-state vector f.rmulism, ＇the photon did not enter the （inner） interf.rometer, the photon never lef. the interf.rometer, but it was there＇. Theref.re, the statement and also the overlapping claim are incorrect.

关键词： in the Nested Mach-Zehnder Interf.rometer An Ideal Experiment to Determine the Past of.a Particle

Competition f.r f.od in 2 populations of.a wild-caught f.sh

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Current Zoology 2018年第5期64卷 615-622页

作者： Pierre J.C. CHUARD grant E. BROWN James W.A. grant Research School of.Biology The Australian National University Canberra ACT 0200 Australia Departmentof.Biology Concordia University 7141 Sherbrooke Street West Montreal Quebec Canada H4B 1R6

Aggressive behavior when competing f.r resources is expected to increase as the ratio of.competitors-to-resource ratio （CRR） units increases. f.males are expected to be more aggressive than males when competing f.r f.od when body size is more strongly related to reproductive suc- cess in f.males than in males, whereas aggression is predicted to decrease under high ambient predation risk by natural selection. Under the risk allocation model, however, individuals under high ambient predation risk are expected to be more aggressive, and f.rage more in the absence of.imminent risk than their low risk counterparts. An interaction between adult sex ratio （i.e., adult males/f.males）, ambient predation risk （high vs. low）, and sex on intrasexual competition f.r mates in Trinidadian guppies Poecilia reticulata has been shown. The interaction suggested an increase in aggression rates as CRR increased, except f.r males f.om the high predation population. To compare the patterns of.competition f.r f.od versus mates, we replicated this study by using f.od patches. We allowed 4 male or 4 f.male guppies f.om high and low predation populations to com- pete f.r 5, 3, or 1 f.od patches. The f.raging rate was higher in a high rather than low ambient pre- dation risk population. Surprisingly, CRR, sex, and population of.origin had no ef.ect on aggression rates. Despite other environmental dif.erences between the 2 populations, the ef.ect of.ambient predation risk may be a likely explanation f.r dif.erences in f.raging rates. These results highlight the importance f.r individuals to secure f.od despite the cost of.competition and predation.

关键词： aggression competitor-to-resource ratio f.raging Poecif.a reticulata population dif.erences predation risk sex

Ef.ects of.Mn content on recrystallization resistance of.AA6082 aluminum alloys during post-def.rmation annealing

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Journal of.Materials Science & Technology 2020年第17期52卷 189-197页

作者： Xiaoming Qian Nick Parson X.-grant Chen Department of.Applied Science University of Quebec at ChicoutimiSaguenay G7H 2B1Canada Arvida Research and Development Centre Rio Tinto AluminumSaguenay G7S 4K8Canada

The microstructural evolutions under as-homogenized and as-def.rmed conditions and af.er the postdef.rmation annealing of.AA6082 aluminum alloys with dif.erent Mn content(0.05 wt.%-1 wt.%)were studied by optical,scanning electron,and transmission electron *** results showed that the presence of.a large amount of.-Al(Mn,f.)Si dispersoids induced by Mn addition signif.cantly improved the recrystallization *** the base alloy f.ee of.Mn,static recrystallization occurred af.er 2 h of.annealing,and grain growth commenced af.er 4 h of.annealing,whereas in Mn-containing alloys,the recovered grain structure was well-retained af.er even 8 h of.*** alloy with 0.5%Mn exhibited the best recrystallization resistance,and a f.rther increase of.the Mn levels to 1%resulted in a gradual reduction of.the recrystallization resistance,the reason f.r which was that recrystallization occurred only in the dispersoid-f.ee zones(Df.s)and the increased Df. f.action with Mn content led to an increase in the recrystallization *** variation in the dispersoid number density and a coarsening of.dispersoids during annealing have a limited inf.uence on the static recrystallization in Mn-containing alloys.

关键词： AA6082 alloys Mn ef.ects Recrystallization resistance Dispersoid precipitation Post-def.rmation annealing