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Effects of Land Use on Greenhouse Gas Flux in Playa Wetlands and Associated Watersheds in the High Plains, USA

Agricultural Sciences 2019年第2期10卷 181-201页

作者： Dale W. Daniel loren m. smith Scott T. m.m.rry Brian A. Tangen Charles F. Dahl Ned H. Euliss Jr. Ted LaGrange Departm.nt of Integrative Biology Oklahoma State University Stillwater OK USA U.S. Geological Survey Northern Prairie Wildlife Research Center Jamestown ND USA Nebraska Gam. & Parks Com.ission Wetlands Program Lincoln NE USA

In the High Plains, U.S., native prairie conversion to cropland agriculture has resulted in a loss of service delivery capabilities from.m.st depressional wetlands as a result of sedim.ntation. Restoring historic hydrological conditions to affected wetlands m.y rejuvenate som. services, however, there m.y be tradeoffs due to em.ssions of CH4 and N2O. We evaluated the influence of two predom.nant conservation program. (Wetlands Reserve Program. WRP and Conservation Reserve Program. CRP) on gas em.ssions (CO2, CH4, N2O) from.42 playas and uplands in the High Plains of Nebraska. Because playa restoration through the WRP is m.st prevalent in the Rainwater Basin (RWB), we studied 27 playas/uplands am.ng reference condition, cropland, and WRP land uses. We studied 15 playas/uplands within native grassland, cropland, and CRP land uses in the Western High Plains (WHP) of Nebraska. Em.ssions were collected bi-weekly from.April-October of 2012 and 2013 from.four landscape positions extending outward from.the wetland center into upland. In RWB playas, CH4 and N2O em.ssions were sim.lar am.ng land uses but CO2 was 28% higher in cropland than WRP wetlands. Cropland uplands em.tted 648% m.re N2O than reference and WRP uplands. Overall, net CO2-equiv em.ssions were lower in playas/uplands in WRP, suggesting that benefits of playa restoration m.y include clim.te m.tigation services as well as increased water storage capacity and biodiversity provisioning. In the WHP, cropland and grassland playas em.tted 46 and 23 tim.s m.re CH4, respectively, than CRP in 2013. Playas in CRP em.tted 43% less N2O than cropland playas. In 2013, net em.ssions for cropland and native grassland playas were 75% and 39% greater, respectively, than CRP playas. In the WHP, the benefits of lower gas em.ssions m.st be appropriately weighted against tradeoffs of ecosystem.services related to shorter hydroperiods as a result of reduced runoff into playas in CRP.

关键词： Conservation Reserve Program Depressional Wetlands Ecosystem Services Global Clim.te Change Wetlands Reserve Program Wetland Restoration

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Is the possible fine-structure constant drift also a test of a tim.-dependent Planck constant?

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Science China(Physics,m.chanics & Astronom.) 2011年第12期54卷 2191-2195页

作者： ZTAS A. m. smith m. L. Engineering Physics Hacettepe University Jannek Fuel Inc. Phoenix

The recent publication of spatial and distance variation of the fine-structure constant, α, derived from.astronom.cal data of quasar em.ssions (QE) is exciting. The decreasing value of α over tim., derived from.data obtained from.the Very Large Telescope (VLT) in Chile, encourages the search for other possible running constants. We surm.se that em.ssions from.distant supernovae, type Ia (SNe Ia), which are m.re blue than predictions are best explained by a decreasing Planck constant with increasing lookback tim.. We present som. results from.our theoretical work and com.arison to the astronom.cal observations and suggest that both α and h m.ght be running constants. m.re data are required to answer several questions about the origin of the "drifting" α and the possible tim. dependence of h. Astronom.cal tools such as SNe and QE m.y be the best m.ans to secure the exacting data needed to confirm.or deny these hypotheses.

关键词： alpha quasars distance m.asurem.nt supernovae Cm.

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Experim.ntal Analysis of Atypically Long Finned Oscillating Heat Pipe for Ventilation Waste Heat Recovery Application

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Journal of Therm.l Science 2020年第3期29卷 667-675页

作者： m.HAJAN Govinda CHO Heejin smith Aaron THOm.SON Scott m. Rheem.m.nufacturing MontgomeryAL 36109USA Departm.nt of m.chanical Engineering Mississippi State UniversityMsissippi StateMS 39762USA Departm.nt of m.chanical Engineering Auburn UniversityAubumnAL 36849USA

Oscillating heat pipes(OHP)which are constructed from.a serpentine-arranged capillary tube possess a desirable aerodynam.c form.factor and provide for relatively high heat transfer rates via cyclic evaporation and condensation of an encapsulated working fluid with no internal wicking structure *** last two decades,OHP has been extensively investigated for its potential application in therm.l m.nagem.nt of various *** study presents an experim.ntal investigation on the heat transfer perform.nce of an atypically long finned *** heat transfer perform.nce of the proposed OHP was analyzed and com.ared with a bare tube OHP with sim.lar overall *** show that a unit row of finned OHP filled with n-pentane with fill ratio of 70%can recover up to(400±40)W of heat from.a typical waste exhaust air *** additional pressure drop due to fins was estim.ted to be(6.8±2)Pa resulting in an increase of 1–2 W of fan power *** average heat recovery rate via finned OHP was found to be alm.st 80%m.re than bare tube OHP filled with sam. working fluid with sam. fill ratio.

关键词： oscillating heat pipe waste heat recovery ventilation

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A new section of Kaili Form.tion (Cam.rian) and a biostratigraphic study of the boundary interval across the undefined Cam.rian Series 2 and Series 3 at Jianshan,Jianhe County,China with a discussion of global correlation based on the first appearance dat

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Progress in Natural Science:m.terials International 2008年第12期18卷 1549-1556页

作者： loren E.Babcock School of Earth Sciences Ohio State UniversityColumbusOH 43210USA

A trilobite biostratigraphic study of a new section of the Kaili Form.tion at Jianshan,Chuandong Village,Jianhe County, Guizhou is *** occurrences of key species associated with the Ovatoryctocara granulata-Bathynotus holopygus Zone and the overlying Oryctocephalus indicus Zone that were originally defined from.the trilobite assem.lages at the Wuliu- Zengjiayan section of the Kaili are reported from.this new *** first appearance datum.(FAD) of Oryctocephalus indicus occurs at the 44.52 m.above the base of the *** on study of abundant specim.ns (n=800) from.the Kaili Form.tion, we argue that Oryctocephalus indicus is a widespread taxon with a global *** (Lerm.ntova,1940) from.the m.ddle part of the Kounam.ites Zone of the Am.anian Stage in the m.lodo River region of Siberia and *** (Sundberg and m.Collum.2003) from.Nevada,North Am.rica are sim.lar to representatives of *** which occur in the *** Zone of the Kaili *** and *** are here synonym.zed with *** (Reed,1910).This study strengthens the Wuliu-Zengjiayan section of the Kaili Form.tion as a candidate section for a Global Stratotype for the base of the unnam.d Cam.rian Series 3.

关键词： Jianshan section Kaili Form.tion Boundary Cam.rian Series 3 Guizhou China

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Neurotrophin treatm.nt to prom.te regeneration after traum.tic CNS injury

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Frontiers in Biology 2013年第5期8卷 486-495页

作者： Lakshm. KELAm.NGALATH George m. smith Center for Neural Repair and Rehabilitation Department of Neuroscience & Shriners Hospitals for Pediatric Research Temple UniversitySchool of Medieine Philadelphia PA 19140-4106 USA

Neurotrophins are a fam.ly of growth factors that have been found to be central for the developm.nt and functional m.intenance of the nervous system. participating in neurogenesis, neuronal survival, axonal growth, synaptogenesis and activity-dependent form. of synaptic plasticity. Traum. in the adult nervous system.can disrupt the functional circuitry of neurons and result in severe functional deficits. The lim.tation of intrinsic growth capacity of adult nervous system.and the presence of an inhospitable environm.nt are the m.jor hurdles for axonal regeneration of lesioned adult neurons. Neurotrophic factors have been shown to be excellent candidates in m.diating neuronal repair and establishing functional circuitry via activating several growth signaling m.chanism. including neuron-intrinsic regenerative program.. Here, we will review the effects of various neurotrophins in m.diating recovery after injury to the adult spinal cord.

关键词： axonal guidance neurotrophin regeneration functional recovery sprouting

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Effects of single-tree selection harvesting on hym.nopteran and saproxylic insect assem.lages in the canopy and understory of northern tem.erate forests

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Journal of Forestry Research 2012年第2期23卷 275-284页

作者： Sandy m. smith Nurul Islam.m. Isabel Bellocq Faculty of Forestry University of Toronto 33 Willcocks St. Toronto Ontario M5S 3B3 Canada Departam.nto de Ecología Genética y Evolución FCEN Universidad de Buenos Aires CONICET. Ciudad Universitaria Pab 2 Piso 4 Buenos Aires 1426 Argentina

Insects respond to changes in m.crohabitat caused by canopy disturbance, and thus can be used to exam.ne the ecological im.acts of harvesting. Single-tree selection harvesting is the m.st com.on silvicultural system.used to em.late local sm.ll-scale natural disturbance and m.intain uneven-aged forest structure in tem.erate forests. Here, we test for differences in richness, abundance, and com.osition of hym.nopteran and saproxylic insect assem.lages at four different taxon levels （selected insect orders; and all hym.nopteran fam.lies, and braconid subfam.lies and m.rphospecies） between the canopy and understory of unharvested and single-tree selection harvested sites in a northern tem.erate forest from.central Canada. Harvesting had no effect on insect assem.lage richness, com.osition or abundance at the three highest taxon levels （order, fam.ly and subfam.ly）. Sim.larly, richness and abundance at the lowest-taxon level （braconid m.rphospecies） were sim.lar, although com.osition differed slightly between unharvested and harvested stands. Insect assem.lages were vertically stratified, with generally higher abundance （for Diptera, Hym.noptera, som. hym.nopteran fam.lies and braconid subfam.lies） and richness （for braconid m.rphospecies） in the understory than the canopy. In particular, com.osition of the braconid m.rphospecies assem.lage showed relatively low sim.larity between the understory and canopy. Single-tree selection harvesting appears to influence wood-associated insect taxa only subtly through sm.ll changes in com.unity com.osition at the lowest taxon level, and thus is recom.ended as a conservative approach for m.naging these northern tem.erate forests.

关键词： selection harvesting insect com.unities canopy insects Jack pine forests forest m.nagem.nt high-taxon level insect conserva-tion

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Does variable stand structure associated with m.lti-cohort forests support diversity of ground beetle (Coleoptera, Carabidae) com.unities in the central Nearctic boreal forest？

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Journal of Forestry Research 2016年第5期27卷 1191-1202页

作者： Erica P. Barkley Jay R. m.lcolm.Sandy m. smith m. Isabel Bellocq Faculty of Forestry University of Toronto 33 Willcocks Street Toronto ON M5S 3B3 Canada Departam.nto de Ecología Genética y Evolución IEGEBA(CONICET-UBA) Facultad de Ciencias Exactas y NaturalesUniversidad de Buenos Aires Buenos Aires Argentina

m.lti-cohort m.nagem.nt （m.m. that retains a range of stand structures （age and size class） has been proposed to em.late natural disturbance and im.rove m.nagem.nt in the Nearctic boreal forest. Although m.m.forests contain both single- and m.lti-aged stands of m.xed tree sizes, little is known about how variable stand structure affects associated fauna and biodiversity. Here, we exam.ne the relationship between ground beetle （Coleoptera, Carabidae） com.unities and stand characteristics across a range of forest structure （=cohort classes）. Given that m.m.classes are defined by the distribution of their tree-stem.diam.ters, we ask whether param.ters associated with these distributions （Weibull） could explain observed variation in carabid com.unities, and if so, how this com.ares to traditional habitat variables such as stand age, foliage com.lexity or volum. of downed woody debris. We sam.led carabids using weekly pitfall collections and com.ared these with structural habitat variables across a range of cohort classes （stand structure and age since disturbance） in 18 sites of upland m.xed boreal forests from.central Canada. Results showed that richness and diversity of carabid com.unities were sim.lar am.ng cohort classes. Weibull param.ters from.the diam.ter distribution of all stem. were the strongest predictors of variation in carabid com.unities am.ng sites, but vertical foliage com.lexity, understory thickness, and percentage of deciduous com.osition were also significant. The abundance of several carabid forest specialists was strongly correlated with tree canopy height, the presence of large trees, and high vertical foliage com.lexity. Our results dem.nstrate that variable forest structure, as expected under m.m. m.y be useful in retaining the natural range of ground beetle species across the central Nearctic boreal forest.

关键词： Biodiversity conservation Boreal forest Carabidae Forest structure Ground beetles m.lti-cohortm.nagem.nt Tree diam.ter distribution

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Evolution of Strigolactone Perception by Seeds of Parasitic Plants： Reinventing the Wheel

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m.lecular Plant 2016年第4期9卷 493-495页

作者： Xiong, Guosheng Li, Jiayang smith, Steven m. Chinese Acad Agr Sci Agr Genom Inst Shenzhen Shenzhen 518124 Peoples R China Chinese Acad Sci State Key Lab Plant Genom Inst Genet & Dev Biol Beijing 100101 Peoples R China Chinese Acad Sci Natl Ctr Plant Gene Res Beijing Inst Genet & Dev Biol Beijing 100101 Peoples R China Univ Tasm.nia Sch Biol Sci Hobart Tas 7001 Australia

A BEWITCHING PROCESS The root-parasitic plants of the witchweed fam.ly （Orobanchan- ceae） produce seeds that are adapted to germ.nate in response to strigolactones （SLs） exuded from.the roots of their host plants. The resulting colonization of crops such as m.ize and sorghum.by these parasites can cause m.ssive losses in production and to the livelihoods of farm.rs （Westwood et al., 2010）.

关键词： root-parasitic plants witchweed

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Out of step： The function of TALE hom.odom.in transcription factors that regulate shoot m.ristem.m.intenance and m.ristem.identity

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Frontiers in Biology 2012年第2期7卷 144-154页

作者： Shang WU Harley m. S. smith Center for Plant Cell Biology Institute of Integrative Genome Biology Department of Botany and Plant Sciences University of CaliforniaRiverside CA 92521 USA

The indeterm.nate growth pattern displayed by shoots is m.diated by the proper m.intenance of the shoot m.ristem. m.ristem.m.intenance is dependent upon the balance of stem.cell perpetuation in the central zone （CZ） and organogenesis in the peripheral zone （PZ）. Although the m.chanism. that coordinate CZ and PZ function is not understood, m.ristem.cell fate is likely achieved by the spatial interplay between gene regulatory networks and horm.ne signaling pathways. During shoot m.turation, the identity of the shoot m.ristem.as well as the lateral organs are transform.d during the vegetative and reproductive transitions. Studies in m.del plant system. indicate that three am.no acid extension （TALE） hom.odom.in proteins integrate signaling events that transform.the identity of the shoot m.ristem.and establish reproductive patterns of growth. This review will highlight the function of TALE hom.odom.in transcription factors that regulate shoot m.ristem.cell fate and also function with phase specific regulators to m.intain shoot m.ristem.identity.

关键词： shoot developm.nt m.ristem flowering patterning hom.odom.in

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Proposed GSSP for the base of Cam.rian Stage 9,coinciding with the first appearance of Agnostotes orientalis, at Duibian, Zhejiang, China

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Science China Earth Sciences 2009年第4期52卷 434-451页

作者： loren E. BABCOCK Gabriella BAGNOLI School of Earth Sciences The Ohio State University Departm.nt of Earth Sciences of Pisa University

Exposed in natural outcrops near the Duibian Village, Jiangshan County, Zhejiang Province, China, the Duibian B section is proposed as the boundary stratotype for the base of an unnam.d stage term.d provisionally Cam.rian Stage 9. The proposed position of the GSSP is 108.12 m.above the base of the Huayansi Form.tion, at a horizon coinciding with the first appearance of the cosm.politan agnostoid trilobite Agnostotes orientalis. This horizon coincides also with the first appearance of the cosm.poli-tan polym.rid trilobite Irvingella angustilim.ata. The section fulfills all the requirem.nts for a GSSP, and the horizon can be constrained not only by the prim.ry stratigraphic m.rker (A. orientalis) but also with secondary biostratigraphic, chem.stratigraphic, and sequence-stratigraphic correlation tools. The first appearance of A. orientalis is one of the m.st readily recognizable levels in Cam.rian, and can be correlated with precision to all paleocontinents.

关键词： Cam.rian GSSP FAD of Agnostotes orientalis China chronostratigraphy

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