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Evaluating and quantifying the effect of various spruce budworm intervention strategies on forest carbon dynamics in Atlantic Canada

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Forest Ecosystems 2022年第4期9卷 547-557页

作者： Zelin liu Changhui Peng david AMaclean louis De Grandpre Jean-Noel Candau Daniel Kneeshaw School of Geographic Sciences Hunan Normal UniversityChangsha410081China Department of Biological Sciences University of Qu�ebec at MontrealMontrealQC H3C 3P8Canada Faculty of Forestry and Environmental Management University of New BrunswickFrederictonNB E3B 5A3Canada laurentian Forestry Centre Canadian Forest ServiceNatural Resources CanadaQC G1V 4C7Canada Great lake Forestry Centre Canadian Forest ServiceNatural Resources CanadaON P6A 2E5Canada

Spruce budworm (SBW) outbreaks are one of the most devastating natural disturbances in spruce-balsam fir forests of eastern North America. Both early intervention strategy (EIS) and foliage protection strategy (FP) are being tested to limit forest losses, but the quantitative impact on forest carbon (C) dynamics is still unclear. In this study, we designed 19 separate scenarios of no intervention or varying success of EIS, FP, and their combination on SBW caused defoliation and mortality. We then used the TRIPlEX-Insect model to quantify their effects on forest C dynamics in the forests of the four provinces of Atlantic Canada. A scenario applying FP to 10%of the area with the greatest potential C losses of living biomass, protecting foliage in 10%of the forests is more realistic than higher proportion of FP given the high cost and large areas involved, resulted in reducing average cumulative net ecosystem productivity (NEP) from 2020 to 2039 by 56%–127%compared to a no outbreak *** results showed that FP would have to be applied everywhere to reduce tree mortality and increase NEP more than 8 years of successful EIS applied. However, if EIS can be successfully implemented for 12 years, it will maintain more forest C than FP applied everywhere during a moderate outbreak. We also found that the combination of EIS followed by FP in 10%of the areas disturbed by the SBW could maintain average cumulative NEP at similar levels to no defoliation in every province of Atlantic Canada. Black/red spruce forests younger than 60years old underwent the smallest changes in C dynamics whether using EIS, FP, or both. This highlights the importance of forest species, forest age, and their interactions on the effectiveness of a treatment during SBW outbreak. Overall, 31%–76%of the study area in Atlantic Canada could convert from a C sink to a source by 2039,if no protective measures are used under the worst-case scenarios, thus contributing to future climate warming.

关键词： Annual defoliation Natural disturbance Forest protection Net ecosystem productivity TRIPlEX-Insect Conifers

Predicting lower limb periprosthetic joint infections: A review of risk factors and their classification

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世界骨科杂志：英文版 2017年第5期8卷 400-411页

作者： david A George lorenzo Drago Sara Scarponi Enrico Gallazzi Fares S Haddad Carlo l Romano Department of Trauma and Orthopaedics University College London Hospitals Microbiological laboratory Orthopaedic Re-search Institute Galeazzi Centre for Reconstructive Surgery and Osteoarticular Infections Orthopaedic Research Institute Galeazzi

AIM To undertook a systematic review to determine factors that increase a patient's risk of developing lower limb periprosthetic joint infections(PJI).METHODS This systematic review included full-text studies that reviewed risk factors of developing either a hip or knee PJI following a primary arthroplasty published from January 1998 to November 2016. A variety of keywords were used to identify studies through international databases referencing hip arthroplasty, knee arthroplasty, infection, and risk factors. Studies were only included if they included greater than 20 patients in their study cohort, and there was clear documentation of the statistical parameter used; specifically P-value, hazard ratio, relative risk, or/and odds ratio(OR). Furthermore a quality assessment criteria for the individual studies was undertaken to evaluate the presence of record and reporting bias. RESUlTS Twenty-seven original studies reviewing risk factors relating to primary total hip and knee arthroplasty infections were included. Four studies(14.8%) reviewed PJI of the hip, 3(11.21%) of the knee, and 20(74.1%) reviewed both joints. Nineteen studies(70.4%) were retrospective and 8(29.6%) prospective. Record bias was identified in the majority of studies(66.7%). The definition of PJI varied amongst the studies but there was a general consensus to define infection by previously validated methods. The most significant risks were the use of preoperative high dose steroids(OR = 21.0, 95%CI: 3.5-127.2, P low 20(OR = 6.00, 95%CI: 1.2-30.9, P = 0.033), diabetes(OR = 5.47, 95%CI: 1.77-16.97, P = 0.003), and coronary artery disease(OR = 5.10, 95%CI: 1.3-19.8, P = 0.017).CONClUSION We have highlighted the need for the provider to optimise modifiable risk factors, and develop strategies to limit the impact of non-modifiable factors.

关键词： Periprosthetic joint infection Risk factor Predictive Hip arthroplasty Knee arthroplasty

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岩石中的压力影形成的实验观测研究

岩石学报 2016年第1期32卷 264-270页

作者：赵永红张琼 Hang WANG 綦超杨天舒 david l KOHlSTEDT 北京大学地球物理系北京100871 美国明尼苏达大学地质与地球物理系 mn55455 中国地质大学北京100083

野外地质观察发现,在大陆地壳变质岩中可以广泛观察到围绕一个大的单晶或者硬质点的两端区域填充低粘度相物质形成的压力影。为了定量研究岩石材料中压力影的形成条件,本文利用高精度Paterson气体介质变形装置,对含有刚性球的圣卡罗橄... 详细信息

野外地质观察发现,在大陆地壳变质岩中可以广泛观察到围绕一个大的单晶或者硬质点的两端区域填充低粘度相物质形成的压力影。为了定量研究岩石材料中压力影的形成条件,本文利用高精度Paterson气体介质变形装置,对含有刚性球的圣卡罗橄榄石和洋中脊玄武岩(MORB)的混合物圆柱型样品进行了高温高压扭转变形试验。变形实验前样品的初始熔融均匀分布,比例为φ≈0.05,变形试件尺寸为D8.9mm×l5.5mm,内含8粒直径约1mm的刚性球。扭转变形试验温度为1473K,围压为300MPa,应变率为γ≈1×10^(-4)s^(-1),最大剪切变形为γ≈4。实验结果表明,岩石受到扭转力的作用产生变形之后,当局部剪切应变达到γ≈1时,可以在刚性球周围形成熔融富集带和熔融贫乏带,即压力影构造,围绕刚性球对称分布。由于熔融分布的不均一性,富集带熔融比例上升,最高可以达到φ_(high)=0.1~0.3,熔融贫乏带熔融比例下降,含量为φ_(low)=0.01~0.02。由于刚性球对其周围的压力分布的扰动区域大约为刚性球的尺度范围,因此,在离开刚性球一定距离后,熔融趋于均匀分布。

关键词：橄榄石扭转实验高温高压部分熔融压力影

Tandem cervical carotid stenting for stenosis with flow diversion embolisation for the treatment of intracranial aneurysms

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Stroke & Vascular Neurology 2019年第1期4卷 43-47页

作者： Jessica K Campos li-Mei lin Narlin B Beaty Matthew T Bender Bowen Jiang david A Zarrin Alexander l Coon Department of Neurosurgery Johns Hopkins University School of MedicineBaltimoreMarylandUSA Department of Neurosurgery University of CaliforniaIrvineOrangeCaliforniaUSA

Background An estimated 2%-3%of the population harbour an intracranial *** atherosclerotic cervical carotid disease is not *** management of these two entities remains a challenge within the *** presentation We report a single case of concomitant carotid stenosis and two ipsilateral unruptured intracranial aneurysms treated with a single-staged cervical carotid stenting and cerebral aneurysm embolisation with the Pipeline embolisation *** No consensus currently exists to guide endovascular treatment of intracranial aneurysms associated with asymptomatic ipsilateral ***,we present a case of asymptomatic moderate carotid stenosis with two ipsilateral intracranial aneurysms and suggest carotid artery stenting takes procedural priority over aneurysm embolisation in single-stage *** rationale for the sequence of neurointerventions is based on the tracking a robust distal access system beyond a stenotic proximal carotid lesion and stabilisation of the ulcerated plaque to avoid thromboembolic complications associated with plaque irritation during aneurysm *** cases and longer follow-up will be needed to further assess the efficacy of this technique.

关键词： aneurysm carotid stenosis

Use of Hi-resolution data for evaluating accuracy of traffic volume counts collected by microwave sensors

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Journal of Traffic and Transportation Engineering(English Edition) 2017年第5期4卷 423-435页

作者： david K.Chang Mitsuru Saito Grant G.Schultz Dennis l.Eggett Hales Engineering lCC LehiUT 84043USA Department of Civil&Environmental Engineering Brigham Young UniversityProvoUT 84602USA Department of Statistics Brigham Young UniversityProvoUT 84602USA

Over the past few years, the Utah Department of Transportation has developed the signal performance metrics （SPMs） system to evaluate the performance of signalized in- tersections dynamically. This system currently provides data summaries for several per- formance measures, one of them being turning movement counts collected by microwave sensors. As this system became public, there was a need to evaluate the accuracy of the data placed on the SPMs. A large-scale data collection was carried out to meet this need. Vehicles in the Hi-resolution data from microwave sensors were matched with the vehicles by ground-truth volume count data. Matching vehicles from the microwave sensor data and the ground-truth data manually collected required significant effort, A spreadsheet- based data analysis procedure was developed to carry out the task. A mixed model analysis of variance was used to analyze the effects of the factors considered on turning volume count accuracy. The analysis found that approach volume level and number of approach lanes would have significant effect on the accuracy of turning volume counts but the location of the sensors did not significantly affect the accuracy of turning volume counts. In addition, it was found that the location of lanes in relation to the sensor did not significantly affect the accuracy of lane-by-lane volume counts. This indicated that accu- racy analysis could be performed by using total approach volumes without comparing specific turning counts, that is, left-turn, through and right-turn movements. In general, the accuracy of approach volume counts collected by microwave sensors were within the margin of error that traffic engineers could accept. The procedure taken to perform the analysis and a summary of accuracy of volume counts for the factor combinations considered are presented in this paper.

关键词： Traffic volume Microwave Signal Performance Accuracy Mixed model analysis of variance

Extensive adhesion formation in a total knee replacement in the setting of a gastrointestinal stromal tumor:A case report

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World Journal of Orthopedics 2022年第5期13卷 538-543页

作者： Steven Mitchell Anderson lee Ryan Stenquist david YatsonskyⅡ Megan l Mooney Vithal B Shendge Department of Orthopaedic Surgery The University of Toledo Medical CenterToledoOH 43614United States

BACKGROUND Gastrointestinal stromal tumors(GISTs)are rare primary neoplasms of the gastrointestinal tract,accounting for 1%to 2%of all gastrointestinal neoplasms *** are frequently discovered incidentally during workup for other diagnosis or intestinal obstruction,as they can present with few or no ***,GISTs confer a high degree of malignant transformation,with a progression in about 10%to 30%of *** SUMMARY A 63-year-old healthy female presented to our institution with complaints of right knee pain and limited passive and active motion in the setting of a previous right total knee arthroplasty(TKA).One year after TKA,the patient was incidentally diagnosed with a GIST,which was successfully *** removal,the patient continued to have limited range of motion of the right knee and subsequently underwent revision *** significant fibrotic adhesions were found encapsulating the femoral and tibial *** patient’s pain improved postoperatively,however,she continued to have decreased range of motion with difficulty *** We propose that this case may demonstrate a proinflammatory milieu arising from a GIST,which had a direct influence on the outcome of recent total knee *** proposed mechanism between neoplastic cytokinetic activity and adhesion formation could have implications on preoperative and postoperative orthopedic management of total knee arthroplasty.

关键词： Gastrointestinal stromal tumor Adhesion formation Total knee arthroplasty Inflammatory response Decreased range of motion Case report

Environmental temperatures,physiology and behavior limit the range expansion of invasive Burmese pythons in southeastern USA

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Integrative Zoology 2012年第3期7卷 271-285页

作者： Elliott R.JACOBSON david G.BARKER Tracy M.BARKER Richard MAUlDIN Michael l.AVERY Richard ENGEMAN Stephen SECOR College of Veterinary Medicine University of FloridaGainesvilleFlorida Vida Preciosa International(VPI) BoerneTexas US Department of Agriculture Wildlife ServicesNational Wildlife Research CenterFort CollinsColorado US Department of Agriculture Wildlife ServicesNational Wildlife Research CenterGainesvilleFlorida Department of Biological Sciences University of AlabamaTuscaloosaAlabamaUSA

A well-established population of Burmese pythons resides in the Everglades of southern *** in part by a report that identified much of southern USA as suitable habitat for expansion or establishment of the Burmese python,we examined the plausibility of this snake to survive winters at sites north of the *** integrated daily low and high temperatures recorded from October to February from 2005-2011 at Homestead,Orlando and Gainesville,Florida;and Aiken,South Carolina,with minimum temperatures projected for python digestion(16℃),activity(5℃)and survival(0℃).Mean low and high temperatures decreased northward from Homestead to Aiken and the number of days of freezing temperatures increased *** was impaired or inhibited for 2 months in the Everglades and up to at least 5 months in Aiken,and activity was increasingly limited northward during these *** of overwinter survivorship document that a single bout of low and freezing temperatures results in python *** capacity for Burmese pythons to successfully overwinter in more temperate regions of the USA is seemingly prohibited because they lack the behaviors to seek refuge from,and the physiology to tolerate,cold *** tropical Southeast Asia is the source of the Everglades Burmese pythons,we predict it is unlikely that they will be able to successfully expand to or colonize more temperate areas of Florida and adjoining states due to their lack of behavioral and physiological traits to seek refuge from cold temperatures.

关键词： ambient temperature Burmese python invasion snake thermal tolerance

Water Vapor Variability in the Tropical Western Pacific from 20-year Radiosonde Data

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Advances in Atmospheric Sciences 2001年第5期18卷 752-766页

作者： Junhong Wang, Harold l. Cole and david J. Carlson National Center for Atmospheric Research P. O, Box 3000,Boulder, CO 80307 National Center for Atmospheric Research Boulder USA

The 20-year (1976-1995) daily radinsonde data at 17 stations in the tropical western Pacific was ana- lyzed. The analysls shows that the atmosphere is more humid in a warmer climate on seasonal,inter-annual and long-term (20-year) time scales, implying a positive water vapor feedback The vertlcal structure of the long-term trends in relative humidity (RH) is distinct from that on short-term (seasonal and inter-annual) time scales, suggesting that observed water vapor changes on short time scales could not be considered as a surrogate of long-term climate change. The increasing trend of RH (3%-5% / decade) in the upper troposphere is stronger than that in the lower troposphere (1 %-2% / decade). Such verthal structure would amplify positive water vapor feedback in comparison to the common assumption of constant RH changes vertically. The empicical orthogonal function (EOF) analysis of vertical structure of RH varmtions shows distinct features of the vert1cal structure of the first three EOFs. The first three EOFs are optimal for repre- sentation of water vapor profiles and provide some hints on physical mechanisms respons1ble for observed humidity variability. Vaisala radiosondes were used at nine stations, and VIZ radiosondes used at other eight stations The Vaisala data are corrected for temperature-dependence error using the correction siheme developed by NCAR / ATD and Vaisala. The comparison of Vaisala and VIZ data shows that the VIZ-measured RHs after October 1993 have a moist bias of - 10% at RHs l changes in- cluding both instruments and reporting practice have been made at Vaisala stations and introduce errors to long-term RH variations.

关键词： Water vapor Radiosonde

Zinc-assisted synthesis of imidazolium-tetrazolate bi-heterocyclic zwitterions with variable alkyl bridge length

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Science China Chemistry 2012年第8期55卷 1620-1626页

作者： DRAB david M. SHAMSHINA Julia l. SMIGlAK Marcin COJOCARU O. Andreea KEllEY Steven P. ROGERS Robin D. Center for Green Manufacturing and Department of Chemistry The University of Alabama Tuscaloosa AL 35487 USA

Zinc halide-complexed alkyl-bridged bi-heterocycles were obtained as zwitterions from the Click reaction of a series of N-cyanoalkyl-N-alkylimidazolium halide ionic liquids with sodium azide. Reaction optimization sho... 详细信息

关键词： Click chemistry ionic liquids heterocycle coordination chemistry