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Cavitation resistance of peduncle,petiole and stem is correlated with bordered pit dimensions in Magnolia grandiflora

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Plant Diversity 2021年第4期43卷 324-330页

作者： Feng-Ping Zhang jiao-Lin Zhang timothy j.Brodribb Hong Hu CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla 666303YunnanChina College of Traditional Chinese Medicine Yunnan Key Laboratory of Dai and Yi MedicinesYunnan University of Chinese MedicineKunming650500YunnanChina Key Laboratory of Economic Plants and Biotechnology Kunming Institute of BotanyChinese Academy of SciencesYunnan Key Laboratory for Wild Plant ResourcesKunming 650201YunnanChina School of Natural Sciences University of TasmaniaPrivate Bag 55HobartTasmania 7001Australia

Variation in resistance of xylem to embolism among flowers,leaves,and stems strongly influences the survival and reproduction of ***,little is known about the vulnerability to xylem embolism under drought stress and their relationships to the anatomical traits of pits among reproductive and vegetative *** this study,we investigated the variation in xylem vulnerability to embolism in peduncles,petioles,and stems in a woody plant,Magnolia *** analyzed the relationships between water potentials that induced 50%embolism(P50)in peduncles,petioles,and stems and the conduit pit traits hypothesized to influence cavitation *** found that peduncles were more vulnerable to cavitation than petioles and stems,supporting the hypothesis of hydraulic vulnerability segmentation that leaves and stems are prioritized over flowers during drought ***,P50 was significantly correlated with variation in the dimensions of inter-vessel pit apertures among peduncles,petioles and *** findings highlight that measuring xylem vulnerability to embolism in reproductive organs is essential for understanding the effect of drought on plant reproductive success and mortality under drought stress.

关键词： Drought Flower Pit traits Xylem embolism Magnolia

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Evaluating rock mass disturbance within open-pit excavations using seismic methods:A case study from the Hinkley Point C nuclear power station

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journal of Rock Mechanics and Geotechnical Engineering 2021年第3期13卷 500-512页

作者： Antony Butcher Anna L.Stork james P.Verdon j-Michael kendall Katrin Plenkers Finlay Booth Marcus Boneham Adrian Koe School of Earth Sciences University of BristolWills Memorial BuildingQueen’s RoadBristolBS81RJUK Department of Earth Sciences University of OxfordSouth Parks RoadOxfordOX13ANUK Gesellschaft für Materialprüfung und Geophysik(GMuG) Bad Nauheim61231Germany Mott MacDonald 10 Temple BackBristolBS16FLUK Atkins The Hub500 Park AvenueAztec WestBristolBS324RZUK Atkins The Axis10 Holliday StreetBirminghamB11TFUK

Understanding rock strength is essential when undertaking major excavation projects,as accurate assessments ensure both safe and cost-effective engineered *** the cost-safety trade-off becomes more imperative during the construction of critical infrastructure such as nuclear power stations,where key components are built within relatively deep *** these engineered slopes is reliant on rock strength models,which are generally parameterised using estimates of rock properties(*** compressive strength,rock disturbance)measured prior to the commencement of ***,the physical process of excavation weakens the remaining rock ***,the model also requires an adjustment for the anticipated rock *** practice,this parameter is difficult to quantify and as a result it is often poorly *** can have a significant impact on the final design and cost of *** present results from passive and active seismic surveys,which image the extent and degree of disturbance within recently excavated slopes at the construction site of Hinkley Point C nuclear power *** from active seismic surveys indicate that the disturbance is primarily confined to 0.5 m from the excavated *** conjunction,passive monitoring is used to detected seismic events corresponding to fracturing on the cm-scale and event locations are in agreement with 0.5 m of disturbance into the rock *** suggests rock disturbance at this site is relatively low and occurred during and immediately after the excavation.A ratio of seismic velocities recorded before and after excavations are used to determine the disturbance parameter required for the Hoek eBrown rock failure criterion,and we assess that rock disturbance is low with the magnitude of the disturbance diminishing more quickly than expected into the excavated *** methods provide a low-cost and quick method to assess excavation related rock mass disturbance,

关键词： Rock mass strength Rock disturbance Seismic tomography Piezoelectric surveys Picoseismicity Acoustic emissions

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Stability of unicortical locked fixation versus bicortical non-locked fixation for forearm fractures

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Bone Research 2014年第2期2卷 131-135页

作者： timothy j Pater Steve I Grindel Gregory j Schmeling Mei Wang Department of Orthopaedic Surgery Medical College of Wisconsin Milwaukee WI USA Orthopaedic & Rehabilitation Engineering Center Marquette University Milwaukee WI USA

Locking plate fixation is being widely applied for fixation of forearm fractures and has many potential advantages, such as fixed angle fixation and improved construct stability, especially in osteoporotic bone. Biomechanical data comparing locking devices to commonly used Low Contact Dynamic Compression （LCDCP） plates for the fixation of forearm fractures has been lacking. The purpose of this study was to compare the fixation stability of a 3.5-mm unicortical locked plate with bicortical non-locked LCDCP plates. Six matched pairs of fresh frozen cadaveric forearms were randomly assigned to unicortical locked and bicortical unlocked groups. Non-destructive four-point bending and torsional test was performed on the ulna and radius separately, using a servohydraulic testing system to obtain construct stiffness of the intact specimens and specimens after osteotomy and plating. The specimens were then loaded to failure to test the fixation strength. The locked unicortical fixation showed significantly higher bending stiffness than the unlocked bicortical fixation, but with significantly lower stiffness and strength in torsion. Fixation strength was comparable between the two groups under bending, but significantly greater in the bicortical non-locked group under torsion. Findings from this study suggest that postoperative rehabilitation protocols may need modification to limit torsional loading in the early stage when using locked unicortical fixation. The study also points out the potential advantage of a hybrid fixation that combines locked unicortical and unlocked bicortical screws.

关键词： Stability of unicortical locked fixation versus bicortical non-locked fixation for forearm fractures

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Added-value of GEO-hyperspectral Infrared Radiances for Local Severe Storm Forecasts Using the Hybrid OSSE Method

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Advances in Atmospheric Sciences 2021年第8期38卷 1315-1333页

作者： Pei WANG Zhenglong LI jun LI timothy jSCHMIT Cooperative Institute for Meteorological Satellite Studies University of Wisconsin-MadisonMadisonWI53706USA Advanced Satellite Product Branch Center for Satellite Applications and ResearchNESDIS/NOAAMadisonWI53706USA

High spectral resolution(or hyperspectral)infrared(IR)sounders onboard low earth orbiting satellites provide high vertical resolution atmospheric information for numerical weather prediction(NWP)*** contrast,imagers on geostationary(GEO)satellites provide high temporal and spatial resolution which are important for monitoring the moisture associated with severe weather systems,such as rapidly developing local severe storms(LSS).A hyperspectral IR sounder onboard a geostationary satellite would provide four-dimensional atmospheric temperature,moisture,and wind profiles that have both high vertical resolution and high temporal/spatial *** this work,the added-value from a GEO-hyperspectral IR sounder is studied and discussed using a hybrid Observing System Simulation Experiment(OSSE)method.A hybrid OSSE is distinctively different from the traditional OSSE in that,(a)only future sensors are simulated from the nature run and(b)the forecasts can be evaluated using real *** avoids simulating the complicated observation characteristics of the current systems(but not the new proposed system)and allows the impact to be assessed against real *** Cross-track Infrared Sounder(CrIS)full spectral resolution(FSR)is assumed to be onboard a GEO for the impact studies,and the GEO CrIS radiances are simulated from the ECMWF Reanalysis v5(ERA5)with the hyperspectral IR all-sky radiative transfer model(HIRTM).The simulated GEO CrIS radiances are validated and the hybrid OSSE system is verified before the impact *** LSS cases from 2018 and 2019 are selected to evaluate the value-added impacts from the GEO CrIS-FSR *** impact studies show improved atmospheric temperature,moisture,and precipitation forecasts,along with some improvements in the wind *** added-value,consisting of an overall 5%Root Mean Square Error(RMSE)reduction,was found when a GEO CrIS-FSR is used in replacement of LEO ones indicat-ing the potential for a

关键词： GEO hyperspectral IR hybrid OSSE satellite data assimilation

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Regulation of cytokine gene expression by orosomucoid in neonatal swine adipose tissue

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journal of Animal Science and Biotechnology 2016年第3期7卷 403-411页

作者： timothy G.Ramsay Margo j.Stoll Le Ann Blomberg Thomas j.Caperna Animal Biosciences and Biotechnology Laboratory USDA/ARSBeltsville Agricultural Research CenterUSDABeltsvilieMD 20705USA

Background： Porcine adipose tissue expresses orosomucoid（ORM1） mRNA, a protein with anti-inflammatory and immunomodulatory properties. Previous research has demonstrated that porcine ORM1 can reduce insulin stimulated glucose metabolism in porcine adipose tissue in vitro. The present study was designed to examine the preweaning ontogeny of ORM1 m RNA abundance in porcine subcutaneous adipose and to determine if ORM1 can regulate m RNA abundance of inflammatory cytokines that contribute to insulin resistance in primary cultures derived from neonatal porcine subcutaneous adipose tissue. Cultures were differentiated in vitro and subsequently the adipocyte containing cultures were incubated for 24 h with 0–5000 ng porcine ORM1/m L medium. Cultures were then harvested, total RNA extracted for use in reverse transcription and the m RNA abundance of cytokine m RNA quantified by real-time ***： ORM1 m RNA abundance within neonatal adipose tissue does not change from d 1 to d 21 of age and is a very small fraction relative to liver m RNA abundance. The ORM1 m RNA level in porcine adipocytes and stromalvascular cells are similar（P 〉 0.05）. Treatment with ORM1 did not affect TNFα（tumor necrosis factor α） m RNA level（P 〉 0.05）, while interleukin 6（IL6） m RNA abundance was reduced 32 % at 1,000 ng ORM1/m L（P 〈 0.01）. However,TNFα protein content in the cell culture media was reduced by ORM1 treatment（5,000 ng/m L, P 〈 0.05）, whereas ORM1 had no detectable effect on the media content of IL6（P 〉 0.05）. The reduction of macrophage migration inhibitory factor（MIF） m RNA abundance by ORM1 was dose dependent（P 〈 0.01）. Monocyte chemotactic protein（MCP） m RNA level was reduced 27 % by 1,000 ng ORM1/m L（P 〈 0.05）.Conclusions： The data suggest that ORM1 has limited effects TNFα, IL6, MIF or MCP expression at the concentrations tested. Secondly, these cytokines do not appear to contribute to the reported insulin resistance induced by ORM1 in porcine adipose tissue in vitro as an in

关键词： Adipose Cytokines Neonate Orosomucoid Swine

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Finite-time circulation changes from topological rearrangement of distinguished curves and non-advective fluxes

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Tropical Cyclone Research and Review 2020年第1期9卷 37-52页

作者： Blake Rutherford timothy j.Dunkerton Northwest Research Associates

A vorticity budget diagnoses the growth or decay of a vortex from advective transport,or non-advective fluxes such as those due to friction or vortex ***,when a budget calculation is performed with respect to a fixed coordinate,errors may result from time-dependence of the flow,leading to disagreement between the vorticity tendency and the observed vorticity *** adaptive Lagrangian coordinate resolves this problem,provided that the resulting Lagrangian structure does not become too *** this study,a numerical simulation of Hurricane Nate(2011),the vorticity tendency is evaluated along distinguished material *** can be no net advective flux along a closed material curve,therefore,the total circulation tendency for a material region includes only the non-advective uxes acting along its boundary.A distinguished set of material curves(DMCs)associated with a distinguished hyperbolic trajectory(DHT)form a Lagrangian topology similar to that of a cat’s eye flow or"pouch"at each Eulerian *** time-dependence of velocities allows additional regions called lobes,which are formed by the intersections of DMCs,to exchange fluid across the vortex boundary by redefining the *** the vortex boundary changes,we refer to this redefinition of material boundary as"topological rearrangement".The method is useful for unsteady cat’s-eye flows and more complex interactions of multiple waves,vortices and background *** advective changes of the vortex circulation are identified by exchanges of the lobes,and all non-advective uxes act between the vortex and either the lobes or environmental *** Lagrangian topology and combination of advective and non-advective uxes relative to the topology is used to describe the evolution of the circulation of Nate during its time of formation.

关键词： red DMC Finite-time circulation changes from topological rearrangement of distinguished curves and non-advective fluxes

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The ruminal microbiome associated with methane emissions from ruminant livestock

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journal of Animal Science and Biotechnology 2017年第2期8卷 289-299页

作者： Ilma Tapio timothy j.Snelling Francesco Strozzi R.john Wallace Green Technology Natural Resources Institute FinlandJokioinenFinland Rowett Institute of Nutrition and Health University of AberdeenForesterhillAberdeen AB16 5BDUK. PTP Via Einstein-Loc.Cascina Codazza26900 Lodiltaly

Methane emissions from ruminant livestock contribute significantly to the large environmental footprint of *** rumen is the principal source of methane, and certain features of the microbiome are associated with low/high methane phenotypes. Despite their primary role in methanogenesis, the abundance of archaea has only a weak correlation with methane emissions from individual animals. The composition of the archaeal community appears to have a stronger effect, with animals harbouring the Methanobrevibacter gottschalki clade tending to be associated with greater methane emissions. Ciliate protozoa produce abundant H_2, the main substrate for methanogenesis in the rumen,and their removal（defaunation） results in an average 11% lower methane emissions in vivo, but the results are not consistent. Different protozoal genera seem to result in greater methane emissions, though community types（A, AB, B and O） did not differ. Within the bacteria, three different ‘ruminotypes＇ have been identified, two of which predispose animals to have lower methane emissions. The two low-methane ruminotypes are generally characterized by less abundant H_2-producing bacteria. A lower abundance of Proteobacteria and differences in certain Bacteroidetes and anaerobic fungi seem to be associated with high methane emissions. Rumen anaerobic fungi produce abundant H_2 and formate, and their abundance generally corresponds to the level of methane emissions. Thus, microbiome analysis is consistent with known pathways for H_2 production and methanogenesis, but not yet in a predictive manner. The production and utilisation of formate by the ruminal microbiota is poorly understood and may be a source of variability between animals.

关键词： Archaea Methane Microbiome Rumen

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The Impact of AIRS Atmospheric Temperature and Moisture Profiles on Hurricane Forecasts: Ike(2008) and Irene(2011)

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Advances in Atmospheric Sciences 2015年第3期32卷 319-335页

作者： ZHENG jing jun LI timothy j.SCHMIT jinlong LI Zhiquan LIU Cooperative Institute for Meteorological Satellite Studies University of Wisconsin-MadisonWisconsin 53706 USA National Satellite Meteorological Center China Meteorological Administration Advanced Satellite Products Branch Center for Satellite Applications and ResearchNESDIS/NOAA Madison WI 53706 USA National Center for Atmospheric Research Boulder Colorado 80305 USA

Atmospheric InfraRed Sounder （AIRS） measurements are a valuable supplement to current observational data,especially over the oceans where conventional data are *** this study,two types of AIRS-retrieved temperature and moisture profiles,the AIRS Science Team product （SciSup） and the single field-of-view （SFOV） research product,were evaluated with European Centre for Medium-Range Weather Forecasts （ECMWF） analysis data over the Atlantic Ocean during Hurricane Ike （2008） and Hurricane Irene （2011）.The evaluation results showed that both types of AIRS profiles agreed well with the ECMWF analysis,especially between 200 hPa and 700 *** average standard deviation of both temperature profiles was approximately 1 K under 200 hPa,where the mean AIRS temperature profile from the AIRS SciSup retrievals was slightly colder than that from the AIRS SFOV *** mean SciSup moisture profile was slightly drier than that from the SFOV in the mid troposphere.A series of data assimilation and forecast experiments was then conducted with the Advanced Research version of the Weather Research and Forecasting （WRF） model and its three-dimensional variational （3DVAR） data assimilation system for hurricanes Ike and *** results showed an improvement in the hurricane track due to the assimilation of AIRS clear-sky temperature profiles in the hurricane *** terms of total precipitable water and rainfall forecasts,the hurricane moisture environment was found to be affected by the AIRS sounding ***,improving hurricane intensity forecasts through assimilating AIRS profiles remains a challenge for further study.

关键词： AIRS data assimilation temperature profile moisture profile hurricane forecast WRF 3DVAR

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Two decades of variable retention in British Columbia: a review of its implementation and effectiveness for biodiversity conservation

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Ecological Processes 2019年第1期8卷 402-423页

作者： William j.Beese john Deal B.Glen Dunsworth Stephen j.Mitchell timothy j.Philpott Vancouver Island University 900 Fifth StreetNanaimoBC V9R 5S5Canada Western Forest Products 118–1334 Island Hwy.Campbell RiverBC V9W 8C9Canada Glen Dunsworth Ecological Consulting 7857 Shangri-La Rd.LantzvilleBC V0R 2H0Canada University of British Columbia 2424 Main MallVancouverBC V6T 1Z4Canada BC Min.of Forests Lands and Nat.Res.Oper400–640 Borland St.Williams LakeBC V2G 4T1Canada

Stand-level retention is an important component of sustainable forest management which aims to balance ecological,social and economic ***-term retention of mature forest structures at the time of harvesting(variable retention)is intended to produce future forest stands that more closely resemble conditions that develop after natural disturbances,thereby maintaining greater diversity of habitats for a variety of *** includes features such as live and dead trees representing multiple canopy layers,undisturbed understory vegetation and coarse woody *** the past two decades,variable retention has become common on forest lands in the temperate rainforests of coastal British Columbia(BC)and has been applied to a lesser extent in inland forest *** review of studies in BC and in similar forest types in our region indicates that both aggregated and dispersed retention can contribute to biodiversity conservation by providing short-term‘life-boating’habitat for some species and by enhancing the structural characteristics of future *** example,greater abundance of species present in the pre-harvest forest have been documented for vegetation,birds,carabid beetles,gastropods,ectomycorrhizal fungi and soil fauna in retention cutblocks compared to *** are,however,some negative consequences for timber production such as wind damage to retained trees and reduced growth rates of tree regeneration compared to *** authors suggest an adaptive management approach for balancing competing objectives when faced with *** includes monitoring the implementation and effectiveness of various strategies for achieving *** two decades of experience applying variable retention harvesting to industrial-scale management of forest lands in BC suggests that it is possible to balance production of wood with biodiversity conservation.

关键词： Alternative silvicultural systems Clearcutting Biological legacies Forest biodiversity Old-growth Variable retention British Columbia

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Notch signaling controls chondrocyte hypertrophy via indirect regulation of Sox9

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Bone Research 2015年第3期3卷 140-151页

作者： Anat Kohn timothy P Rutkowski Zhaoyang Liu Anthony j Mirando Michael j Zuscik Regis j O'Keefe Matthew j Hilton Department of Orthopaedics and Rehabilitation The Center for Musculoskeletal Research University of Rochester Medical Center Department of Biomedical Genetics University of Rochester Medical Center Department of Biology University of Rochester Department of Orthopaedic Surgery Duke Orthopaedic Cellular Developmental and Genome Laboratories Duke University School of Medicine Department of Orthopaedic Surgery Washington University School of Medicine

RBPjk-dependent Notch signaling regulates both the onset of chondrocyte hypertrophy and the progression to terminal chondrocyte maturation during endochondral ossification. It has been suggested that Notch signaling can regulate Sox9 transcription, although how this occurs at the molecular level in chondrocytes and whether this transcriptional regulation mediates Notch control of chondrocyte hypertrophy and cartilage development is unknown or controversial. Here we have provided conclusive genetic evidence linking RBPjk-dependent Notch signaling to the regulation of Sox9 expression and chondrocyte hypertrophy by examining tissuespecific Rbpjk mutant（Prx1Cre;Rbpjkf/f）, Rbpjk mutant/Sox9 haploinsufficient（Prx1Cre;Rbpjkf/f;Sox9f/1）,and control embryos for alterations in SOX9 expression and chondrocyte hypertrophy during cartilage development. These studies demonstrate that Notch signaling regulates the onset of chondrocyte maturation in a SOX9-dependent manner, while Notch-mediated regulation of terminal chondrocyte maturation likely functions independently of SOX9. Furthermore, our in vitro molecular analyses of the Sox9 promoter and Notch-mediated regulation of Sox9 gene expression in chondrogenic cells identified the ability of Notch to induce Sox9 expression directly in the acute setting, but suppresses Sox9 transcription with prolonged Notch signaling that requires protein synthesis of secondary effectors.

关键词： Figure Notch signaling controls chondrocyte hypertrophy via indirect regulation of Sox9 NICD SOX

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