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Effects of fragmentation on the seed predation and dispersal by rodents differ among species with different seed size

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Integrative Zoology 2017年第6期12卷 468-476页

作者： Qiong CHEN kyle W.TOMLINSON Lin CAO Bo WANG Center for Integrative Conservation Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglaYunnanChina University of Chinese Academy of Sciences BeijingChina

Fragmentation influences the population dynamics and community composition of vertebrate ***mentation effects on rodent species in forests may,in turn,affect seed predation and dispersal of many plant *** studies have usually addressed this question by monitoring a single species,and their results are *** few studies have discussed the fragmentation effect on rodent-seed interaction among tree species with different seed sizes,which can significantly influence rodent foraging preference and seed *** that fruiting periods for many coexisting plant species overlap,the changing foraging preference of rodents may substantially alter plant *** this study,we monitored the dispersal and predation by rodents of 9600 seeds,belonging to 4 Fagaceae species with great variation in seed size,in both the edge and interior areas of 12 tropical forest fragments ranging in area from 6.3 to 13872.9 ha in Southwest *** results showed that forest fragmentation altered the seed fates of all the species,but the intensity and even the direction of fragmentation effect differed between species with large versus small *** the seeds harvested,fragment size showed negative effects in forest interiors but positive effects at edges for the 2 large-seeded species,but showed little effect for the 2 small-seeded *** the seeds removed,negative effects of fragment size only existed among the small-seeded *** different fragmentation effect on seed dispersal and predation among plant species may,in turn,translate into the composition differences of the regeneration of the whole fragmented forest.

关键词： edge effect forest fragmentation plant-rodent interaction seed size

Periodic orbits in the Chermnykh problem

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Astrodynamics 2017年第1期1卷 41-55页

作者： Xiangyuan Zeng kyle T.Alfriend School of Automation Beijing Institute of TechnologyBeijing 100081China Department of Aerospace Engineering Texas A&M UniversityCollege StationTexas 77840USA

Periodic orbits in irregular gravitational fields are significant for an understanding of dynamical behaviors around asteroids as well as the engineering aspect for deep space explorations. The rotating mass dipole, referred to as the Chermnykh problem, is a good alternative model to study qualitative dynamical environments near elongated asteroids, like the asteroid 1620 Geographos, 216 Kleopatra, or 25143 Itokawa. In this paper a global searching method is adopted to search for periodic orbits around the dipole model based on the concept of Poincaré section of surface. Representative families of periodic orbits are illustrated with respect to all three topological cases of the dipole model. Topological transitions of orbits during iso-energetic continuations are also presented as well as identification of new types of periodic orbits.

关键词： periodic orbits the Chermnykh problem topological transition iso-energetic continuation

Prime waterfront real estate： Apple snails choose wild taro for oviposition sites

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Current Zoology 2011年第5期57卷 630-641页

作者： Colin H. kyle Alexis W. KROPF Romi L. BURKS Department of Ecology and Evolution University of Chicago Chicago IL 60637 USA Department of Biology Southwestern University Georgetown TX 78626 USA

While difficult to prevent introductions, scientific research can help guide control efforts of exotic, invasive species. South American island apple snailsPomacea insularumhave quickly spread across the United States Gulf Coast and few control measures exist to delay their spread. Usually occupying cryptic benthic habitats, female apple snails crawl out of the water to deposit large, bright pink egg clutches on emergent objects. To help identify the most likely place to find and remove clutches, we conducted four lab experiments to investigate what specific object qualities (i.e. material; shape and height; plant species; natural and artificial) attractedP. insularumfemales to lay clutches. In our fourth experiment, we specifically examined the relationship between female size and reproductive output. To further understand reproductive output, we quantified experimental clutch characteristics (height above water, dimensions, mass, approximate volume, number of eggs, hatching efficiency).Pomacea insu-larumfemales laid more clutches on plant material, chose round over flat surfaces and failed to differentiate between tall and short structures. In comparison to a common native plant in the eastern US,Pontederia cordata, snails clearly preferred to lay clutches on a widely distributed exotic, invasive plant (wild taro,Colocasia esculenta). Unexpectedly, smaller snails showed higher overall total fecundity as well as more eggs per clutch than larger snails. Therefore, hand removal efforts of large females may not be enough to slow down clutch production. Collectively, our results indicate that conservationists and managers should search emergent plants forP. insularumclutches carefully to guard against established populations.

关键词：福寿螺芋头野生房地产网站产卵海滨外来入侵物种

Recent advances on the role of long non-coding RNAs in Alzheimer’s disease

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Neural Regeneration Research 2020年第12期15卷 2253-2254页

作者： kyle Doxtater Manish K.Tripathi Mohammad Moshahid Khan Department of Pharmaceutical Sciences University of Tennessee Health Science CenterMemphisTNUSA Department of immunology and Microbiology University of Texas Rio Grande ValleyMcAllenTXUSA Department of Neurology College of MedicineDivision of Rehabilitation Sciences and Department of Physical TherapyCollege of Health ProfessionsUniversity of Tennessee Health Science CenterMemphisTNUSA

Dementia is a progressive cognitive impairment that affects the activities of daily ***’s disease (AD) is the most common form of the dementia worldwide accounting for 60-80%of all dementia *** an estimated cost exceeding$290 billion in the USA,understanding and development of future therapeutic strategies is *** this perspective,we will be examining the current thinking of AD research and therapeutic strategies,while proposing a possible new direction for diagnosis,understanding,and treatment targets.

关键词： Alzheimer diagnosis exceeding

Neutron transmission imaging with a portable D-T neutron generator

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Radiation Detection Technology and Methods 2022年第2期6卷 234-243页

作者： Phillip Kerr Nerine Cherepy Jennifer Church Gary Guethlein Jim Hall Colby McNamee Sean o'Neal kyle Champley Andy Townsend Mayuki Sasagawa Anthony Hardy Saphon Hok Lawrence Livermore National Laboratory LivermoreCA 94550USA

Purpose A portable fast-neutron imaging system is being developed to provide complementary information to field X-ray *** include inspection of vehicles and infrastructure for corrosion,measurement of material levels in containers,and inspection of munitions and suspicious *** fast-neuron imaging generally provides lower imaging resolution compared to X-rays,fast-neutron interaction cross-sections have a weak dependence on material *** enables imaging of low-Z materials inside high-Z ***,we discuss the limitations and current improvements in fast-neuron *** Limitations in portable fast-neutron imaging systems include low D-T neutron generator output,low light pro-duction in ZnS(Cu)imaging scintillators,low resolution due to scintillator thickness and D-T spot size,and digital-panel darknoise that varies in time and position and that can be 100×larger than the neutron *** have made improvements in these areas through development of a segmented high light yield scintillator,panel noise mitigation techniques,and testing of new high-output,small spot size D-T neutron *** The segmented high light yield fast-neutron scintillator demonstrated 5×increase in light compared to ZnS(Cu).An additional 2×improvement in signal-to-noise was demonstrated with panel-noise mitigation *** MCNP calculations also show good agreement with neutron imaging results Conclusions We have demonstrated improvements in fast-neutron imaging through development of a segmented high light yield neutron scintillator,mitigation of digital panel noise,and preliminary testing with new high-output,small spot size D-T neutron *** have also demonstrated good results modeling fast-neutron images and scatter effects using MCNP.

关键词： Fast-neutron radiography Portable neutron imaging Neutron scintillators Monte Carlo simulation

Influence of smoke, heat and fire on germination of woody species occurring in the dry valleys of southwest China

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Journal of Plant Ecology 2019年第6期12卷 931-940页

作者： Mareike Roeder Weidong Yang kyle W.Tomlinson Center for Integrative Conservation Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglunMenglaYunnan 666303China Institute of Floodplain Ecology Karlsruhe Institute of TechnologyJosefstraße 1D–76437 RastattGermany

Aims Savannahs depend on fire for their *** influences regeneration from seeds in several ways:it converts the environment into a more open space which can benefit the establishment of seedlings,and fire itself can also enhance germination by chemical and physical cues,such as smoke and *** is limited information as to how seed of Asian savannah species respond to fire,even though Asia has several dry vegetation types that are associated with *** main question was whether fire enhances or triggers the germination of woody species occurring in southwest Chinese dry valleys,which have savannah *** We conducted tests with heat(80°C)and smoke solution treatments,and tests with real fire by burning grass on top of sand trays containing *** tested 35 species,including savannah species,and gully and forest *** on seed availability,not all species were tested for all ***-six species had total germination>4%and these were used for *** Findings Heat increased germination of three species(strongest reaction:Dodonaea viscosa),smoke increased germination of five species(strongest reaction:Calotropis gigantea).Both treatments decreased germination for five and seven species,*** fire was detrimental for most species,except for ***,which is known to respond positively to heat *** though fire-related cues were not a trigger for germination for most species in our study,fire could still be crucial for regeneration by competition release.

关键词： smoke water burning biomass germination time Dodonaea viscosa Calotropis gigantea seed mass water content dark germination

Overcoming barriers to the clinical utilization of iPSCs:reprogramming efficiency,safety and quality

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Protein & Cell 2012年第11期3卷 834-845页

作者： Suying Cao kyle Loh Yangli Pei Wei Zhang Jianyong Han State Key Laboratory for Agrobiotechnology College of Biological SciencesChina Agricultural UniversityBeijing 100193China Stem Cell and Developmental Biology Genome Institute of Singapore138672Singapore

Differentiated cells can be reprogrammed into pluripotent stem cells,known as“induced pluripotent stem cells”(iPSCs),through the overexpression of defined transcription *** creation of iPSC lines has opened new avenues for patient-specific cell replacement therapies for regenerative ***,the clinical utilization of iPSCs is largely impeded by two *** first limitation is the low efficiency of iPSCs generation from differentiated *** second limitation is that many iPSC lines are not authentically pluripotent,as many cell lines inefficiently differentiate into differentiated cell types when they are tested for their ability to complement embryonic ***,the“quality”of iPSCs must be increased if they are to be differentiated into specialized cell types for cell replacement *** these two limitations is paramount to facilitate the widespread employment of iPSCs for therapeutic ***,we summarize recent progress made in strategies enabling the efficient production of high-quality iPSCs,including choice of reprogramming factors,choice of target cell type,and strategies to improve iPSC quality.

关键词： iPSCs reprogramming embryonic stem cells efficiency and quality

A Note on the Generalized and Universal Associated Legendre Equations

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Communications in Theoretical Physics 2018年第7期69卷 19-24页

作者： Keegan L.A.Kirk kyle R.Bryenton Nasser Saad School of Mathematical & Computational Sciences University of Prince Edward Island

A class of second-order differential equations commonly arising in physics applications are considered,and their explicit hypergeometric solutions are provided. Further, the relationship with the Generalized and Universal Associated Legendre Equations are examined and established. The hypergeometric solutions, presented in this work,will promote future investigations of their mathematical properties and applications to problems in theoretical physics.

关键词： Legendre 微分方程通用笔记应用程序理论物理数学性质

Guest editorial–special issue on ground control in mining in 2020

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International Journal of Mining Science and Technology 2021年第1期31卷 1-2页

作者： Michael M.Murphy Ted Klemetti Heather Lawson Brijes Mishra kyle Perry CDC NIOSH PittsburghPA 15236USA CDC NIOSH SpokaneWA 99207USA Department of Mining Engineering West Virginia UniversityMorgantown 26501USA Department of Mining Engineering Missouri University of Science and TechnologyRollaMO 65409USA

Ground control is the science of studying and controlling the behavior of rock strata in response to mining ***-control-related research has seen significant advancements over the last 40 years,and these accomplishments are well documented in the proceedings of the annual International Conference on Ground Control in Mining(ICGCM)[1].The ICGCM is a forum to promote closer communication among researchers,consultants,regulators,manufacturers,and mine operators to expedite solutions to ground control problems in mining[2–7].Fundamental research and advancements in ground control science define the central core of the conference *** information to mine operators is a priority,as the conference goal is to offer solutions-oriented *** addition,the conference has included innovative technologies and ideas in miningrelated fields such as exploration,geology,and surface and underground mining in all *** new ground control technologies and design standards adopted by the mining industry were first discussed at *** conference is recognized as the leading international forum for introducing new ground-control-related research and products.

关键词： operators closer accomplishment