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Acta geologica Sinica(English Edition) 2016年第5期90卷 1699-1712页

作者： christopher BAIYEgUNHI Oswald gWAVAVA School of Computational Sciences Faculty of Science and AgricultureUniversity of Fort Hare

gravity modelling was carried out along five profiles that traverse the Eastern Cape Province of South Africa in order to determine the depositional surface and isochore thickness of the Ecca *** models of the subsurface rock density reveal that the Ecca group has a maximum vertical thickness of about 3215 ± 160 *** maximum depositional surface（elevation）above sea level for the Ecca sediments is about 500 m,whilst the depth below sea level reaches about10000 *** of the isochore thickness maps with the depositional surfaces shows that the sediments in the basement highs were subsided,deformed,eroded and deposited in the basement *** basement highs served as the source area（s） for the sediments in the basement lows,thus basement highs are characterized with thin sediment cover whilst the lows have thick sediment cover.

关键词： ediment isochore thickness depositional surface Ecca group basement highs and lows

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A material change for ultra-high precision force sensing

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Light(Science & Applications) 2024年第11期13卷 2443-2445页

作者： christopher Perrella Kishan Dholakia Centre of Light for Life and School of Biological Sciences University of AdelaideAdelaideSouth Australia 5005Australia ARC Centre of Excellence in Optical Microcombs for Breakthrough Science(COMBS) University of AdelaideAdelaideSouth Australia 5005Australia SUPA School of Physics and AstronomyUniversity of St AndrewsSt Andrews KY169SSScotland

An original form of photonic force microscope has been *** with a trapped lanthanide-doped crystal of nanometric dimensions,a minimum detected force of the order of 110 aN and a force sensitivity down to 1.8 fN/ffiffi... 详细信息

关键词： dimensions high force

Endocasts-the direct evidence and recent advances in the study of human brain evolution

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Progress in Natural Science:Materials International 2007年第9期17卷 993-1002页

作者： christopher J.Norton 86011-4099 AZ Beijing 100044 China Flagstaff Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Laboratory of Quaternary Paleontology Northern Arizona University USA

Brain evolution is one of the most important aspects of human evolution,usually studied through *** of fossil hominid endocasts allows inferences on functional anatomy,physiology,and *** this paper,we describe the general features of endocast studies and review some of the major topics in *** are:absolute and relative brain size evolution;brain shape variation;brain asymmetry and lateralization;middle meningeal vessels and venous sinuses;application of computed tomography and virtual imaging;the history of Chinese brain endocast *** particular,this review emphasizes endocast studies on Chinese hominin fossils.

关键词： endocast human fossil brain evolution cranial capacity human evolution

Is sympatric speciation in nature only possible with micro-parapatry? A new case study of glacial lake cyprinid fishes

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National Science Review 2022年第12期9卷 21-23页

作者： christopher H.Martin Department of Integrative Biology University of California Museum of Vertebrate Zoology University of California

Although numerous theoretical models of the feasibility and necessary conditions for sympatric speciation abound in the literature,clear-cut examples in nature remain ***,as always in speciation research,this statement strongly depends on your definition of sympatric speciation [1-3].If using the biogeographic definition of sympatric speciation as divergence between individuals in a population within’cruising range’of each other [4],

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FINITE ELEMENT EXTERIOR CALCULUS FOR PARABOLIC EVOLUTION PROBLEMS ON RIEMANNIAN HYPERSURFACES

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Journal of Computational Mathematics 2018年第6期36卷 792-832页

作者： Michael Hoist christopher Tiee Department of Mathematics University of California San Diego La Jolla CA 92093 USA

Over the last ten years, Finite Element Exterior Calculus （FEEC） has been developed as a general framework for linear mixed variational problems, their numerical approximation by mixed methods, and their error analysis. The basic approach in FEEC, pioneered by Arnold, Falk, and Winther in two seminal articles in 2006 and 2010, interprets these problems in the setting of Hilbert complexes, leading to a more general and complete understanding. Over the last five years, the FEEC framework has been extended to a broader set of problems. One such extension, due to Hoist and Stern in 2012, was to problems with variational crimes, allowing for the analysis and numerical approximation of linear and geometric elliptic partial differential equations oil Riemannian manifolds of arbitrary spatial dimension. Their results substantially generalize the existing surface finite element approximation theory in several respects. In 2014, gillette, Hoist, and Zhu extended FEEC in another direction, namely to parabolic and hyperbolic evolution systems by combining the FEEC framework for elliptic operators with classical approaches for parabolic and hyperbolic operators, by viewing solutions to the evolution problem as lying in Bochner spaces （spaces of Banach-space valued parametrized curves）. Related work on developing an FEEC theory for parabolic evolution problems has also been done independently by Arnold and Chen. In this article, we extend the work of gillette-Holst- Zhu and Arnold-Chen to evolution problems on Riemannian manifolds, through tile use of framework developed by Holst and Stern for analyzing variational crimes. We establish a priori error estimates that reduce to the results from earlier work in tile flat （non-criminal） setting. Some numerical examples are also presented.

关键词： FEEC Elliptic equations Evolution equations Approximation theory Inf-supconditions A priori estimates Variational crimes Equations on manifolds

Signals and noise in the octavolateralis systems: What is the impact of human activities on fish sensory function?

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Integrative Zoology 2015年第1期10卷 4-14页

作者： christopher B.BRAUN Department of Psychology Hunter CollegeCity University of New YorkNew YorkNYUSA

The octavolateralis systems of fishes include the vestibular,auditory,lateral line and electrosensory *** are united by common developmental and neuro-computational features,including hair cell sensors and computations based on cross-neuron analyses of differential hair cell stimulation *** systems also all use both spectral and temporal filters to separate signals from each other and from noise,and the distributed senses(lateral line and electroreception)add spatial filters as *** all sensory systems,these sensors must provide the animal with guidance for adaptive behavior within a sensory scene composed of multiple stimuli and varying levels of ambient noise,including that created by human *** the extreme,anthropogenic activities impact the octavolateralis systems by destroying or degrading the habitats that provide ecological resources and sensory *** slightly lesser levels of effect,anthropogenic pollutants can be damaging to fish tissues,with sensory organs often the most *** exposed sensory cells of the lateral line and electrosensory systems are especially sensitive to aquatic *** still lesser levels of impact,anthropogenic activities can act as both acute and chronic stressors,activating hormonal changes that may affect behavioral and sensory ***,human activities are now a nearly ubiquitous presence in aquatic habitats,often with no obvious effects on the animals exposed to *** noise,indigenous and industrial fishing techniques,and all the ancillary noises of human civilization form a major part of the soundscape of *** fish use these new sources of information about their habitat is a new and burgeoning field of study.

关键词： audition,electrosense lateral line soundscape underwater noise

Spherical Tropical geometry:a Survey of Recent Developments

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Acta Mathematica Sinica,English Series 2018年第3期34卷 454-465页

作者： Kiumars KAVEH christopher MANON Department of Mathematics University of PittsburghPittsburghPAUSA Department of Mathematics Univcrsity of KentuckyLexingtonKYUSA

This is a survey of some recent results on spherical tropical geometry.

关键词： Tropical geometry reductive group action spherical variety grbner theory

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Using agent-based simulation to assess diseaseprevention measures during pandemics

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Chinese Physics B 2021年第9期30卷 643-651页

作者： Yunhe Tong christopher King Yanghui Hu Department of Engineering Mathematics University of BristolBristol BS81UBUK State Key Laboratory of Fire Science University of Science and Technology of ChinaHefei 230027China

Despite the growing interest in macroscopic epidemiological models to deal with threats posed by pandemics such as COVID-19,little has been done regarding the assessment of disease spread in day-to-day life,especially within buildings such as supermarkets where people must obtain necessities at the risk of exposure to ***,we propose an integrated customer shopping simulator including both shopper movement and choice behavior,using a force-based and discrete choice model,*** a simple extension to the force-based model,we implement the following preventive measures currently taken by supermarkets;social distancing and one-way systems,and different customer habits,assessing them based on the average individual disease exposure and the time taken to complete shopping(shopping efficiency).Results show that maintaining social distance is an effective way to reduce exposure,but at the cost of shopping *** find that the one-way system is the optimal strategy for reducing exposure while minimizing the impact on shopping *** should also visit supermarkets less frequently,but buy more when they do,if they wish to minimize their *** hope that this work demonstrates the potential of pedestrian dynamics simulations in assessing preventative measures during pandemics,particularly if it is validated using empirical data.

关键词： pedestrian dynamics occupant exposure COVID-19 simulation study

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Automatic sub-pixel co-registration of Landsat-8 Operational Land Imager and Sentinel-2A Multi-Spectral Instrument images using phase correlation and machine learning based mapping

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International Journal of Digital Earth 2017年第12期10卷 1253-1269页

作者： Sergii Skakun Jean-Claude Roger Eric F.Vermote Jeffrey g.Masek christopher O.Justice Department of geographical Sciences University of MarylandCollege ParkMDUSA NASA goddard Space Flight Center Code 619 GreenbeltMDUSA NASA goddard Space Flight Center Code 618 GreenbeltMDUSA

This study investigates misregistration issues between Landsat-8/Operational Land Imager and Sentinel-2A/Multi-Spectral Instrument at 30 m resolution,and between multi-temporal Sentinel-2A images at 10 m resolution using a phase-correlation approach and multiple transformation ***-registration of 45 Landsat-8 to Sentinel-2A pairs and 37 Sentinel-2A to Sentinel-2A pairs were *** correlation proved to be a robust approach that allowed us to identify hundreds and thousands of control points on images acquired more than 100 days ***,misregistration of up to 1.6 pixels at 30 m resolution between Landsat-8 and Sentinel-2A images,and 1.2 pixels and 2.8 pixels at 10 m resolution between multi-temporal Sentinel-2A images from the same and different orbits,respectively,were *** non-linear random forest regression used for constructing the mapping function showed best results in terms of root mean square error(RMSE),yielding an average RMSE error of 0.07±0.02 pixels at 30 m resolution,and 0.09±0.05 and 0.15±0.06 pixels at 10 m resolution for the same and adjacent Sentinel-2A orbits,respectively,for multiple tiles and multiple conditions.A simpler 1st order polynomial function(affine transformation)yielded RMSE of 0.08±0.02 pixels at 30 m resolution and 0.12±0.06(same Sentinel-2A orbits)and 0.20±0.09(adjacent orbits)pixels at 10 m resolution.

关键词： Sub-pixel co-registration phase correlation misregistration Landsat-8 Sentinel-2 machinelearning random forest

Improvement of quantitative testing of liver function in patients with chronic hepatitis C after installment of antiviral therapy

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World Journal of gastroenterology 2005年第35期11卷 5521-5524页

作者： Matthias Ocker Marion ganslmayer Steffen Zopf Susanne gahr christopher Janson Eckhart g. Hahn Christoph Herold Department of Medicine I University Erlangen-Nuernberg Ulmenweg 18 Erlangen 91054 Germany

MM： To investigate if and to what extent antiviral therapy influenced a broad panel of quantitative testing of liver function （QTLF）. METHODS： Fifty patients with chronic hepatitis C were either treated with interferon （n = 8）, interferon/ribavirin （n = 19） or peg-interferon/ribavirin （n = 23）. Quantitative testing of liver function, including aminopyrine breath test （ABT）, galactose elimination capacity （gEC）, sorbitol clearance （SCI） and indocyanine green clearance （ICg） was performed before and 3 mo after initiation of antiviral therapy. RESULTS： After 3 mo of antiviral treatment, 36 patients showed normal transaminases and were negative for HCVRNA, 14 patients did not respond to therapy. ABT and gEC as parameters of microsomal and cytosolic liver function were reduced in all patients before therapy initiation and returned to normal values in the 36 therapy responders after 3 too. Parameters of liver perfusion （SCl and ICg） were not affected by antiviral therapy. In the 14 non-responders, no changes in QTLF values were observed during the treatment period. CONCLUSION： ICg and SCI remained unaffected in patients with chronic hepatitis C, while ABT and gEC were significantly compromised. ABT and gEC normalized in responders to antiviral therapy. Early determination of ABT and gEC may differentiate responders from non-responders to antiviral treatment in hepatitis C.

关键词： Aminopyrine breath test galactose eliminationcapacity Indocyanine green clearance Sorbitol clearance Hepatitis C Interferon Ribavirin