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THE ORIGIN OF THE NIANGTZEKUAN TUFA

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地质学报 1930年第3期 216-221页

作者： george b. bARbOUR Department of Geology Yenching University

For centuries the tufa of Niangtzekuan has possessed a peculiar fascination. It is to be seen decorating rock-gardens and fish-ponds all over North China, and is sold in curio-markets for use in flower-bowls, and as o... 详细信息

关键词： THE ORIGIN OF THE NIANGTZEKUAN TUFA down

THE SUPERFICIAL DEPOSITS OF YUTAOHO, SHANSI

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地质学报 1930年第4期 350-357页

作者： george b. bARbOUR Department of Geology Yenching University

An account is given of the structural relations of a curious Pleistocene conglomerate and a calcareous tufa in Yutaoho valley the interpretation of which bears on the problem of the Pleistocene history of Shansi. Obse... 详细信息

关键词： THE SUPERFICIAL DEPOSITS OF YUTAOHO SHANSI

Hepatocellular carcinoma in chronic hepatitis b patients under antiviral therapy

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World Journal of Gastroenterology 2013年第47期19卷 8822-8830页

作者： John Vlachogiannakos george Papatheodoridis Academic Department of Gastroenterology Athens University Medical SchoolLaiko General Hospital11527 AthensGreece

Patients with chronic hepatitis b are at increased risk of hepatocellular carcinoma(HCC),while the inhibition of viral replication can represent a reasonable target for HCC ***-αtherapy results in decreased HCC risk,which is more evident in patients with high baseline HCC *** majority of chronic hepatitis b patients are treated with a nucleos(t)ide analogue(NA)for several reasons including the nonsustained response after interferon-α.The effect of the first licensed and low genetic barrier NA,lamivudine,on HCC incidence,has been repeatedly ***,compared to no treatment,reduces the HCC incidence,which may increase again in cases with lamivudine *** data with the currently first-line NAs,entecavir and tenofovir,suggest that they also reduce the HCC *** treatment benefit in reduction of the HCC incidence is always greater in patients with high baseline HCC risk,particularly cirrhotics,and without virological remission under entecavir/***,the HCC risk is not eliminated even in the vast majority of patients who remain in virological remission under entecavir/***,patients at increased baseline HCC risk should continue to undergo HCC surveillance even if they have achieved complete long-term inhibition of viral replication and improvements in liver histology.

关键词： Chronic hepatitis b Hepatocellular carcinoma Interferon Lamivudine Adefovir Entecavir Tenofovir Virological remission Cirrhosis

Interfacial Strategies for Smart Slippery Surfaces

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Journal of bionic Engineering 2020年第4期17卷 633-643页

作者： Glen McHale Rodrigo Ledesma-Aguilar Gary george Wells Smart Materials&Surfaces Laboratory Faculty of Engineering and EnvironmentNorthumbria UniversityNewcastle upon TyneNE18STUK

The problem of contact line pinning on surfaces is pervasive and contributes to problems from ring stains to ice *** we provide a single conceptual framework for interfacial strategies encompassing five strategies for modifying the solid-liquid interface to remove pinning and increase droplet *** biomimetic strategies are included,(i)reducing the liquid-solid interfacial area inspired by the Lotus effect,(ii)converting the liquid-solid contact to a solid-solid contact by the formation of a liquid marble inspired by how galling aphids remove honeydew,and(iii)converting the liquid-solid interface to a liquid-lubricant contact by the use of a lubricant impregnated surface inspired by the Nepenthes Pitcher *** further strategies are,(iv)converting the liquid-solid contact to a liquid-vapor contact by using the Leidenfrost effect,and(v)converting the contact to a liquid-liquid-like contact using slippery omniphobic covalent attachment of a liquid-like coating(SOCAL).Using these approaches,we explain how surfaces can be designed to have smart functionality whilst retaining the mobility of contact lines and ***,we show how droplets can evaporate at constant contact angle,be positioned using a Cheerios effect,transported by boundary reconfiguration in an energy invariant manner,and drive the rotation of solid components in a Leidenfrost heat *** conceptual framework enables the rationale design of surfaces which are slippery to liquids and is relevant to a diverse range of applications.

关键词： superhydrophobicity SLIPS liquid marbles leidenfrost SOCAL

Statistical analysis on the influence of mechanical parameters in the vibration of pylons

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Earthquake Engineering and Engineering Vibration 2023年第1期22卷 263-278页

作者： Georgios I.Dadoulis george D.Manolis Laboratory for Experimental Mechanics Department of Civil EngineeringAristotle UniversityThessaloniki 54124Greece

We present a statistical investigation of the degree of influence that assumptions made in relation to the mechanical parameters of a pylon have on its ground-induced *** study is set up by using as a key kinematic variable the displacement at the top of a reference,a stand-alone pylon with a uniform cross-section and fixity at its ***,statistics are produced using a dimensionless displacement ratio defined between the‘parental’and the‘subsidiary’cases,the latter defined for the pylon(a)resting on compliant soil,(b)having an attached top mass,and(c)being non-uniform with ***,two materials are examined,namely,steel and reinforced concrete(R/C).More specifically,this displacement ratio is independent of the excitation and plays the role of a transfer function between the base and the top of the *** horizontal and vertical motions are considered,and the equations of motion are solved in the frequency *** ensuing statistical analysis is conducted for the following parameter combinations:(a)pylon founded on soft,intermediate,and stiff soil;(b)low,intermediate,and high-mass ratios of the attached mass to the pylon′s mass;(c)a constant and quadratic degree of pylon tapering with *** correlation coefficients are calculated for all the above combinations to arrive at statistical results that establish validity bounds and quantify the degree of influence of each assumption on the pylon′s response.

关键词： pylons statistical analysis spearman coefficients structural vibrations elastic waveguides attached masses soil springs tapering

Demographic variation and habitat specialization of tree species in a diverse tropical forest of Cameroon

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Forest Ecosystems 2014年第4期1卷 201-213页

作者： David Kenfack george b Chuyong Richard Condit Sabrina E Russo Duncan W Thomas Center for Tropical Forest Science - Forest GEO Botany Department Smithsonian Tropical Research Institute Department of botany and Plant Physiology University of Buea Center for Tropical Forest Science Smithsonian Tropical Research Institute School of biological Sciences University of Nebraska Department of biological Sciences Washington State University

background： Many tree species in tropical forests have distributions tracking local ridge-slope-valley topography. Previous work in a 50-ha plot in Korup National Park, Cameroon, demonstrated that 272 species, or 63% of those tested, were significantly associated with topography. Methods： We used two censuses of 329,000 trees ≥1 cm dbh to examine demographic variation at this site that would account for those observed habitat preferences. We tested two predictions. First, within a given topographic habitat, species specializing on that habitat （＇residents＇） should outperform species that are specialists of other habitats （＇foreigners＇）. Second, across different topographic habitats, species should perform best in the habitat on which they specialize （＇home＇） compared to other habitats （＇away＇）. Species＇ performance was estimated using growth and mortality rates. Results： In hierarchical models with species identity as a random effect, we found no evidence of a demographic advantage to resident species. Indeed, growth rates were most often higher for foreign species. Similarly, comparisons of species on their home vs. away habitats revealed no sign of a performance advantage on the home habitat. Conclusions＂ We reject the hypothesis that species distributions along a ridge-valley catena at Korup are caused by species differences in trees _〉1 cm dbh. Since there must be a demographic cause for habitat specialization, we offer three alternatives. First, the demographic advantage specialists have at home occurs at the reproductive or seedling stage, in sizes smaller than we census in the forest plot. Second, species may have higher performance on their preferred habitat when density is low, but when population builds up, there are negative density-dependent feedbacks that reduce performance. Third, demographic filtering may be produced by extreme environmental conditions that we did not observe during the census interval.

关键词： tree Demographic variation and habitat specialization of tree species in a diverse tropical forest of Cameroon Figure

A Poincaré Inequality in a Sobolev Space with a Variable Exponent

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Chinese Annals of Mathematics,Series b 2011年第3期32卷 333-342页

作者： Philippe G.CIARLET george DINCA Department of Mathematics City University of Hong Kong Faculty of Mathematics and Computer Science University of Bucharest

Let Ω be a domain in RN. It is shown that a generalized Poincaré inequality holds in cones contained in the Sobolev space Wl,P（）（Ω）, where p（.）： Ω → [1, ∞[ is a variable exponent. This inequality is itself a corollary to a more general result about equivalent norms over such cones. The approach in this paper avoids the difficulty arising from the possible lack of density of the space ;D（Ω） in the space {v ∈ Wl,P（）（Ω）; tr v = 0 on δΩ}. Two applications are also discussed.

关键词： Poincaré inequality Sobolev spaces with variable exponent

ITERATIVE REGULARIZATION METHODS FOR NONLINEAR ILL-POSED OPERATOR EQUATIONS WITH M-ACCRETIVE MAPPINGS IN bANACH SPACES

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Acta Mathematica Scientia 2015年第6期35卷 1318-1324页

作者： Ioannis K.ARGYROS Santhosh george Department of Mathematical Sciences Cameron University Department of Mathematical and Computational Sciences National Institute of Technology Karnataka

In this paper, a modified Newton type iterative method is considered for ap- proximately solving ill-posed nonlinear operator equations involving m-accretive mappings in banach space. Convergence rate of the method is obtained based on an a priori choice of the regularization parameter. Our analysis is not based on the sequential continuity of the normalized duality mapping.

关键词： nonlinear ill-posed equations iterative regularization m-accretive operator Newton type method

LAVRENTIEV'S REGULARIZATION METHOD FOR NONLINEAR ILL-POSED EQUATIONS IN bANACH SPACES

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Acta Mathematica Scientia 2018年第1期38卷 303-314页

作者： Santhosh george C.D.SREEDEEP Department of Mathematical and Computational Sciences NIT Karnataka

In this paper, we deal with nonlinear ill-posed problems involving m-accretive mappings in banach spaces. We consider a derivative and inverse free method for the imple- mentation of Lavrentiev regularization method. Using general HSlder type source condition we obtain an optimal order error estimate. Also we consider the adaptive parameter choice strategy proposed by Pereverzev and Schock （2005） for choosing the regularization parameter.

关键词： nonlinear ill-posed problem banach space Lavrentiev regularization m-accretive mappings adaptive parameter choice strategy