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effects of a regenerating matrix on the survival of birds in tropical forest fragments

Avian Research 2020年第1期11卷 16-24页

作者： Jared D.Wolfe Philip C.Stouffer Richard O.Bierregaard Jr David A.Luther thomas e.Lovejoy College of Forest Resources and environmental Science Michigan Technological UniversityHoughtonMI 49931USA Biological Dynamics of Forest Fragments Project Instituto Nacional de Pesquisas da AmazoiaManaus 69011Brazil College of Renewable Natural Resources Louisiana State University AgCenterLouisiana State UniversityBaton RougeLA 70803USA Biology Department George Mason University4400 University Drive MS3EFairfaxVA 22030USA

Background: Vast areas of lowland neotropical forest have regenerated after initially being cleared for agricultural purposes. The ecological value of regenerating second growth to forest-dwelling birds may largely depend on the age of the forest, associated vegetative structure, and when it is capable of sustaining avian demographics similar to those found in pristine ***: To determine the influence of second growth age on bird demography, we estimated the annual survival of six central Amazonian bird species residing in pristine forest, a single 100 and a single 10 ha forest fragment, taking into consideration age of the surrounding matrix(i.e. regenerating forest adjacent to each fragment) as an explanatory ***: Study species exhibited three responses: arboreal, flocking and ant-following insectivores(Willisornis poecilinotus, Thamnomanes ardesiacus and Pithys albifrons) showed declines in survival associated with fragmentation followed by an increase in survival after 5 years of matrix regeneration. Conversely, Percnostola rufifrons, a gap-specialist, showed elevated survival in response to fragmentation followed by a decline after 5 years of regeneration. Lastly, facultative flocking and frugivore species(Glyphorynchus spirurus and Dixiphia pipra, respectively) showed no response to adjacent clearing and subsequent ***: Our results in association with previous studies confirm that the value of regenerating forest surrounding habitat patches is dependent on two factors: ecological guild of the species in question and second growth age. Given the rapid increase in survival following succession, we suggest that the ecological value of young tropical forest should not be based solely on a contemporary snapshot, but rather, on the future value of mature second growth as well.

关键词： Amazon fragmentation Brazil Matrix Second growth Survival Tropical bird

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Abelian quotients and orbit sizes of linear groups

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Science China Mathematics 2020年第8期63卷 1523-1534页

作者： thomas Michael Keller Yong Yang Department of Mathematics Texas State UniversitySan MarcosTX 78666USA Key Laboratory of Group and Graph Theories and Applications Chongqing University of Arts and SciencesChongqing 402160China

Let G be a finite group,and let V be a completely reducible faithful finite G-module(i.e.,G≤GL(V),where V is a finite vector space which is a direct sum of irreducible G-submodules).It has been known for a long time that if G is abelian,then G has a regular orbit on *** this paper we show that G has an orbit of size at least|G/G′|on *** generalizes earlier work of the authors,where the same bound was proved under the additional hypothesis that G is *** completely reducible modules it also strengthens the 1989 result|G/G′|er and Guralnick.

关键词： abelian quotients orbits of group actions linear groups

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Prediction of plane-strain specimen geometry to efficiently obtain a forming limit diagram by Marciniak test

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Journal of Iron and Steel Research International 2018年第5期25卷 539-545页

作者： Qing-bao Yang Jun-ying Min John e. Carsley Yuan-yuan Wen Bernd Kuhlenkotter thomas B. Stoughton Jian-ping Lin School of Mechanical engineering Tongji UniversityShanghai 201804 China General Motors Research & Development WarrenMI 48095-9055 USA Chair of Production Systems Ruhr-University BochumBochum 44780 Germany

Plane-strain forming limit strain （also known as FLD0） is an important data point on a forming limit diagram （FLD）. The effects of friction coefficients and material parameters on the specimen width associated with the FLDo （W FLD0） in Marciniak test were studied by finite element simulation. WFLD0 was expressed as a function of the Lankford coefficients, n-value, k-value and sheet thickness and validated with various sheet materials. The determination of W FLD0 is of significance not only to reduce iterative attempts to accurately obtain FLDo, but also to obtain a full valid FLD with the least number of test specimens, which largely increases the efficiency and reduces cost to experimentally measure valid FLDs.

关键词： Forming limit test ·Sheet metal· Plane-strain state· Marciniak test

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Association of rs1568885, rs1813443 and rs4411591 polymorphisms with anti-TNF medication response in Greek patients with Crohn's disease

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World Journal of Gastroenterology 2014年第13期20卷 3609-3614页

作者： Diamantis thomas Maria Gazouli Theodoros Karantanos Stella Rigoglou Georgios Karamanolis Konstantinos Bramis George Zografos George e Theodoropoulos Colorectal Unit 1st Department of Propaedeutic Surgery"Hippokrateio" HospitalSchool of MedicineUniversity of Athens11527 AthensGreece Department of Basic Medical Science Laboratory of BiologySchool of MedicineUniversity of Athens11527 AthensGreece Gastroenterology Unit 2nd Department of Surgery"Aretaieio" HospitalUniversity of AthensAthens 11527Greece

AIM: To investigate the correlation between rs1568885, rs1813443 and rs4411591 polymorphisms and response to infliximab in a cohort of Greek patients with Crohn’s disease (CD).

关键词： Crohn’ s disease, Treatment response, Infliximab, Polymorphisms

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Damping of Pressure Pulsations in Mobile Hydraulic Applications by the Use of Closed Cell Cellular Rubbers Integrated into a Vane Pump

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Journal of Bionic engineering 2017年第4期14卷 791-803页

作者： David Bach Tom Masselter thomas Speck Plant Biomechanics Group Freiburg Botanic Garden Faculty of Biology University of Freiburg Schginzlestr. 1 79104 Freiburg Germany Freiburg Materials Research Center (FMF) Stefan-Meier-StraBe 21 79104 Freiburg Germany Competence Networks Biomimetic and BIOKON e. V. Schainzlestr. 1 79104 Freiburg Germany

The present study evaluates the potential of a bio-inspired pulsation damper in a vane pump used in mobile hydraulic ap- plications. Pressure pulsations caused by such positive displacement pumps can lead to malfunctions and noise in a hydraulic system. A common measure to reduce pressure pulsations is the integration of pressure pulsation dampers downstream of the pump. This type of damping measure can also be found in biology as e.g. in the human blood circulatory system. Such working principles found in living organisms offer a high potential for a biomimetic transfer into technical applications. The newly developed bio-inspired damper consists of cellular rubbers with non-linear viscoelastic material properties. In order to evaluate the new damping method, pressure pulsations were measured at two different back pressures and at a wide engine speed range of the vane pump. For further assessment, different setups, varying the stiffness of the cellular rubber materials and the damper volume, were tested. Within the tested back pressures, the pressure pulsations could be reduced by up to 40%. The developed integrated pulsation damper offers a high potential to dampen pressure pulsations of positive displacement pumps used in mobile hydraulic applications ooeratin~ below 10 bar.

关键词： pressure pulsations pressure ripple vane pump bio-inspired pulsation damping cellular rubbers flexible foams

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Corrosion behavior of metallic alloys in molten chloride salts for thermal energy storage in concentrated solar power plants： A review

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Frontiers of Chemical Science and engineering 2018年第3期12卷 564-576页

作者： Wenjin Ding Alexander Bonk thomas Bauer Institute of engineering Thermodynamics German Aerospace Center (DLR) 70569 Stuttgart Germany Institute of engineering Thermodynamics German Aerospace Center (DLR) 51147 Cologne Germany

Recently, more and more attention is paid on applications of molten chlorides in concentrated solar power （CSP） plants as high-temperature thermal energy storage （TeS） and heat transfer fluid （HTF） materials due to their high thermal stability limits and low prices, compared to the commercial TeS/HTF materials in CSP- nitrate salt mixtures. A higher TeS/HTF operating temperature leads to higher efficiency of thermal to electrical energy conversion of the power block in CSP, however causes additional challenges, particularly increased corrosiveness of metallic alloys used as contain- ers and structural materials. Thus, it is essential to study corrosion behaviors and mechanisms of metallic alloys in molten chlorides at operating temperatures （500-800℃） for realizing the commercial application of molten chlorides in CSe The results of studies on hot corrosion of metallic alloys in molten chlorides are reviewed to understand their corrosion behaviors and mechanisms under various conditions （e.g., temperature, atmosphere）. emphasis has also been given on salt purification to reduce corrosive impurities in molten chlorides and development of electrochemical techniques to in-situ monitor corrosive impurities in molten chlorides, in order to efficiently control corrosion rates of metallic alloys in molten chlorides to meet the requirements of industrial applications.

关键词： corrosion mechanisms impurities metallic corrosion salt purification electrochemical techniques

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A fully abstract semantics for value-passing CCS for trees

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Frontiers of Computer Science 2019年第4期13卷 828-849页

作者： Ying JIANG Shichao LIU thomas eHRHARD State Key Laboratory of Computer Science Institute of Software Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China CNRS IRIF UMR 8243 Univ Paris Diderot Sorbonne Paris Cite F-75205 Paris France

We propose a fully abstract semantics for valuepassing CCS for trees (VCCTS) with the feature that processes are located at the vertices of a graph whose edges describe possible interaction capabilities. The operational semantics is given both in terms of a reduction semantics and in terms of a labelled transition semantics. We develop a theory of behavioral equivalences by introducing both weak barbed congruence and weak bisimilarity. In particular, we show that, on image-finite processes, weak barbed congruence coincides with weak bisimilarity. To illustrate potential applications and the powerful expressiveness of VCCTS, we formally compare VCCTS with some well-known models, e.g., dynamic pushdown networks, top-down tree automata and value-passing CCS.

关键词： process calculus non-interleaving semantics barbed congruence bisimulation

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Nitrogen enrichment alters carbon fluxes in a New england salt marsh

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ecosystem Health and Sustainability 2018年第11期4卷 34-44页

作者： emily K.Geoghegan Joshua S.Caplan Francine N.Leech Paige e.Weber Caitlin e.Bauer thomas J.Mozdzer Department of Biology Bryn Mawr CollegeBryn MawrPAUSA

Introduction:Nitrogen enrichment of coastal salt marshes can induce feedbacks that alter ecosystem-level processes including primary production and carbon *** the rising interest in coastal blue carbon,the effects of chronic nutrient enrichment on blue carbon processes have rarely been measured in the context of experimental ***,we examined the ecosystem-level effects of nitrate(NO3)enrichment on the green-house gas dynamics of a Spartina alterniflora-dominated salt *** measured CO2 and CH4 fluxes using static chambers through two growing seasons in a salt marsh that was nitrogen-enriched for 13 years and compared fluxes to those from a reference ***:We found that nitrogen enrichment increased gross primary productivity(GPP)by 7.7%and increased ecosystem respiration(Recd)by 20.8%.However,nitrogen enrichment had no discernible effect on net ecosystem exchange(Nee).Taken together,these results suggest that nitrogen-induced stimulation of Reco could transform this salt marsh from a carbon sink into a source of carbon to the atmos ***:Our results complement prior findings of nitrogen enrichment weakening soil structure and organic matter stability in tidal salt marshes,suggesting that increased nutrient inputs have the potential to alter the carbon storage function of these ecosystems through enhanced microbial respiration of previously sequestered carbon.

关键词： Spartina alterniflora blue carbon eutrophication gross primaryproductivity net ecosystemexchange nitrogen ecosystem respiration tidalsaltmarsh

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On the nonlinear transformation of breaking and non-breaking waves induced by a weakly submerged shelf

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Journal of Hydrodynamics 2018年第4期30卷 592-604页

作者： Giorgio Contento Guido Lupieri thomas Puzzer Department of engineering and Architecture University of Trieste

The interaction of regular quasi-monochromatic waves with a weakly submerged rectangular shelf is studied by means of CFD simulations. The fundamental incident wave frequency is kept constant for the full set of simulated cases, while the incident wave amplitude is made increase progressively, so that the interaction with the shelf is dominated by almost inviscid non-linear flow for the smallest and by breaking for the highest incident waves. A parameter identification（PI） procedure is used to adapt a reduced model to the highly resolved time-space matrix of wave elevations obtained from the numerical simulations, on the weather and lee side respectively. In particular the wave number and the frequency of the component waves in the reduced model are left uncoupled, thus computed by the PI independently. The comparison of simulated data with experiments generally shows a very good agreement. Free/locked, incident/reflected, first/higher order wave components are quantified accurately by the PI and the energy transfer to super-harmonics is clearly evidenced. Moreover the results of the PI show clearly a very large increase in the phase speed of the higher order free waves on the lee side of the shelf, with increasing deviation from the linear behavior with increasing incident wave amplitude.

关键词： Nonlinear wave transformation submerged shelf wave breaking coupled space-time domain analysis reduced model parameter identification

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Geotritium： Implications of DeP Weak Interaction Fusion in Magmatic Systems

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Journal of Physical Science and Application 2016年第4期6卷 1-7页

作者： thomas e. Ward Techsource Incorporated 20251 Century Blvd. Germantown Maryland 20874 US.A

Tritium in the environment comes from several sources： anthropogenic nuclear weapons and commercial nuclear reactors, atmospheric cosmic-ray production, and geotritium. Geotritium and its decay product 3He is found in the earth＇s magmatic system evidenced by tritium emission from volcanoes and 3He anomalies associated with MORB （Mid-Ocean Ridge Basalts）, OIB （Oceanic Island Basalts） and deep mantle plumes. The 3He can be accounted for assuming a radiogenic 3T（3He） component as opposed to a primordial source. It is proposed that the d（pe-, v） 3t weak interaction fusion （WIF） reaction （Q = 5.474 MeV） is the source for both the geotritium and anomalous 3He found in nature. The radiogenic lifetime for the WIF reaction, dp ＋ e- →3t ＋ V in a metal hydride geologic environment, such as Fell/FeD in the core and mantle of the earth, was calculated to be tdep = 1.61x10^9 yr. The anomalous 3He produced by the WIF reaction, a radio chronometer, was used to correlate and date mantle basalt processes deep within the earth. The p（pe-,v）d WIF reaction （Q = 1.442 MeV） with a lifetime Tpep = 2.54x10^12 yr. was also examined as a possible geoehronometer for the formation interval of the oceans, the duration of the earth＇s melting and degassing prior to the formation of the oceans. The formation age of the oceans was determined to be 3.93 billion years ago in good agreement with geologic magmatic activity and continental crust formation.

关键词： Geotritium mantle helium fusion geochronology.

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