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Influence of climate fluctuations on Pinus palustris growth and drought resilience

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Forest Ecosystems 2023年第6期10卷 681-689页

作者： Joao Campoa joshua Puhlick CENsE–Center for Environmental and sustainability Research CHANGE-Global Change and Sustainability InstituteDepartment of Environmental Sciences and EngineeringNOVA School of Science and TechnologyNOVA University LisbonCampus de Caparica2829-516 CaparicaPortugal The Jones Center at Ichauway 3988 Jones Center Drive39870NewtonGAUSA

The longleaf pine(Pinus palustris Mill.)ecosystem is an endangered ecosystem in the southeastern UsA,and efforts to restore the species are ***,in recent decades,the region has experienced drastic fluctuations between wet and dry growing season conditions from year to year,and it is not fully understood how these fluctuations have influenced the growth of *** address this topic,we cored *** trees in woodlands of southwest Georgia and used dendrochronology techniques to determine how climate fluctuations have influenced the growth and drought resilience of *** also cored slash pine(Pinus elliottii Engelm.)trees in the same woodlands to compare growth between *** *** growth was less impacted by adverse climate conditions compared to ***,the strength of correlations between *** growth and temperature,precipitation,and Palmer Drought severity Index(PDsI)changed over *** recent decades,climate conditions during the growing season became more influential on *** growth than the previous year's *** is concerning given that drought severity during the growing season has been *** results also indicate that *** was less resilient to droughts during the 2000s and 2010s than to those of the *** this new climate paradigm,our results suggest that *** might be more susceptible to growth reductions and less resistant to droughts than once *** work highlights the importance of understanding the impact of novel climate conditions on *** and has implications for restoration efforts,such as using silvicultural treatments that reduce tree vulnerability to drought(e.g.,thinning)and promote other climate-adapted species in mixture with ***.

关键词： Longleaf pine slash pine Pinus elliottii Climate change Dendrochronology Dendroclimatology Forest disturbances

Influence of indoor airflow on airborne disease transmission in a classroom

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Building simulation 2024年第3期17卷 355-370页

作者： Mojtaba Zabihi Ri Li joshua Brinkerhoff school of Engineering Faculty of Applied ScienceUniversity of British ColumbiaKelownaCanada

It has been widely accepted that the most effective way to mitigate airborne disease transmission in an indoor space is to increase the ventilation airflow,measured in air change per hour(ACH).However,increasing ACH did not effectively prevent the spread of *** better understand the role of ACH and airflow large-scale patterns,a comprehensive fully transient computational fluid dynamics(CFD)simulation of two-phase flows based on a discrete phase model(DPM)was performed in a university classroom setting with people *** investigations encompass various particle sizes,ventilation layouts,and flow *** findings demonstrated that the particle size threshold at which particles are deemed airborne is highly influenced by the background flow strength and large-scale flow pattern,ranging from 5µm to 10µm in the cases *** effects of occupants are significant and must be precisely accounted for in respiratory particle transport *** enhanced ventilation design(UFAD-CDR)for university classrooms is introduced that places a premium on mitigating airborne disease *** to the baseline design at the same ACH,this design successfully reduced the maximum number density of respiratory particles by up to 85%.A novel airflow-related parameter,Horizontality,is introduced to quantify and connect the large-scale airflow pattern with indoor aerosol *** underscores that ACH alone cannot ensure or regulate air *** addition to the necessary ACH for air exchange,minimizing horizontal bulk motion is essential for reducing aerosol transmissibility within the room.

关键词： aerosol transmission airflow pattern horizontality COVID-19 simulation classroom ventilation

Regular Orbits of Extra-special Groups

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Algebra Colloquium 2016年第4期23卷 681-688页

作者： joshua E. Goodson Texas A&M University at Galveston Department of General Academics P.O. Box 1675 Galveston Texas 77553 USA

In this paper, for odd primes p we find a recursive formula for the number of regular orbits of an extra-special p-group of exponent p2 acting on a faithful irreducible module over a finite field. This complements an ... 详细信息

关键词： extra-special orbits counting p-groups

Fundamental behaviours of production traffic in underground mine haulage ramps

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International Journal of Mining science and Technology 2015年第1期25卷 7-14页

作者： Haviland David Marshall joshua Golder Associates Ltd. The Robert M. Buchan Department of Mining Queen’s University

Ramps(or declines) are often used in underground mines to transport ore, waste, materials, and personnel. This paper studies mine ramp productivity and presents results from a set of computer simulations designed to model the fundamental behaviours of ramp haulage systems. simulations show that, under fundamental assumptions without random disturbances, the haulage system always converges to a periodic behaviour in the steady state, but that productivities vary between equilibria. simulations also demonstrate how productivity per vehicle does not necessarily decrease as more vehicles are added and,for example, in the five-vehicle case, how a 3.1% improvement can be achieved over the use of four vehicles. The result reveals the inefficiency of commonly-used lockout-style vehicle coordination strategies,and suggests a possible avenue for improving the productivity of haulage ramps by controlling the system to achieve more productive behaviours.

关键词： Underground miningFleet managementDiscrete-time simulationVehicle dispatching

Ensemble-based Kalman Filters in strongly Nonlinear Dynamics

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Advances in Atmospheric sciences 2009年第3期26卷 373-380页

作者： Zhaoxia PU joshua HACKER Department of Atmospheric sciences University of Utah USA National Center for Atmospheric Research USA

This study examines the effectiveness of ensemble Kalman filters in data assimilation with the strongly nonlinear dynamics of the Lorenz-63 model, and in particular their use in predicting the regime transition that occurs when the model jumps from one basin of attraction to the other. Four configurations of the ensemble-based Kalman filtering data assimilation techniques, including the ensemble Kalman filter, en- semble adjustment Kalman filter, ensemble square root filter and ensemble transform Kalman filter, are evaluated with their ability in predicting the regime transition （also called phase transition） and also are compared in terms of their sensitivity to both observational and sampling errors. The sensitivity of each ensemble-based filter to the size of the ensemble is also examined.

关键词： ensemble Kalman filter nonlinear data assimilation Lorenz model

How aerosol direct effects influence the source contributions to PM2.5 concentrations over southern Hebei, China in severe winter haze episodes

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Frontiers of Environmental science & Engineering 2018年第3期12卷 145-157页

作者： Litao Wang joshua s. Fu Wei Wei Zhe Wei Chenchen Meng simeng Ma Jiandong Wang Department of Environmental Engineering Hebei University of Engineering Handan 056038 China Department &Civil and Environmental Engineering The University of Tennessee Knoxville TN 37996 USA Department of Environmental science Beijing University of Technology Beijing 100124 China state Key Joint Laboratory of Environment simulation and Pollution Control School of Environment Tsinghua University Beijing 100084 China

Beijing-Tianjin-Hebei area is the most air polluted region in China and the three neighborhood southern Hebei cities, shijiazhuang, Xingtai, and Handan, are listed in the top ten polluted cities with severe PM2.5 pollution. The objective of this paper is to evaluate the impacts of aerosol direct effects on air aualitv over the southern Hebei cities, as well as the im0acts when considering those effects on source apportionment using three dimensional air quality models. The WRF/Chem model was applied over the East Asia and northern China at 36 and 12 km horizontal grid resolutions, respectively, for the period of January 2013, with two sets of simulations with or without aerosol-meteorology feedbacks. The source contributions of power plants, industrial, domestic, transportation, and agriculture are evaluated using the Brute-Force Method （BFM） under the two simulation configurations. Our results indicate that, although the increases in PM2.5 concentrations due to those effects over the three southern Hebei cities are only 3%-9% on monthly average they are much more significant under high PM2.5 Ioadmgs （-50 gg.m - when PM25 concentrations are higher than 400μg.m^-3）. When considering the aerosol feedbacks, the contributions of industrial and domestic sources assessed using the BFM will obviously increase （e.g., from 30% 34% to 32%-37% for industrial）, especiallY3under high PM2.5 loadings （e.g., from 36%-44% to 43%-47% for domestic when PM2.5〉400μg·m^-3）. Our results imply that the aerosol direct effects should not be ignored during severe pollution episodes, especially in short-term source apportionment using the BFM.

关键词： Aerosol direct effect PM2.5 southern Hebei WRF/Chem Haze

Anterior glenohumeral instability:Current review with technical pearls and pitfalls of arthroscopic soft-tissue stabilization

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World Journal of Orthopedics 2021年第1期12卷 1-13页

作者： John M Apostolakos joshua Wright-Chisem Lawrence V Gulotta samuel A Taylor joshua s Dines Department of sports Medicine and shoulder surgery Hospital for Special SurgeryNew YorkNY 10021United States

The glenohumeral joint(GHJ)allows for a wide range of motion,but is also particularly vulnerable to episodes of *** GHJ instability is especially frequent among young,athletic populations during contact sporting *** first time dislocators can be managed non-operatively with a period of immobilization and rehabilitation,however certain patient populations are at higher risk for recurrent instability and may require surgical intervention for adequate *** of the optimal treatment strategy should be made on a case-by-case basis while weighing both patient specific factors and injury patterns(i.e.,bone loss).The purpose of this review is to describe the relevant anatomical stabilizers of the GHJ,risk factors for recurrent instability including bony lesions,indications for arthroscopic vs open surgical management,clinical history and physical examination techniques,imaging modalities,and pearls/pitfalls of arthroscopic soft-tissue stabilization for anterior glenohumeral instability.

关键词： Arthroscopic soft-tissue Anterior instability Glenohumeral Functional anatomy Recurrent instability

Effect of laser textured surface with different patterns on tribological characteristics of bearing material AIsI 52100

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Journal of Central south University 2020年第8期27卷 2210-2219页

作者： PAUL joshua s DINEsH BABU P school of Mechanical Engineering SASTRA Deemed UniversityThanjavur 613401TamilnaduIndia

Chrome steels are used in bearings since they possess high strength and wear ***,when those parts are in service,failure happens due to sliding friction before the *** improve the durability of the American Iron and steel Institute(AIsI)52100 chromium steel,in this work,the effect of laser surface texturing(LsT)was *** the different patterns of circle and ellipse comparing with the untextured samples,the wear behavior was investigated using the pin-on-disc *** lubricant used for wear analysis is semisolid lithium grease National Lubricating Grease Institute lubricant(sKF NLGI-3).sliding wear analysis was conducted at different loads of 10 N,30 N and 50 N for the sliding speed of 750 r/min and 1400 r/*** wear morphology was analyzed using a scanning electron microscope(sEM).The roughness of the samples was found using a white light *** effect of different patterns like circle and ellipse,alter the friction and wear properties of chromium alloy was observed compared with the untextured *** shows considerable reduction in friction and wear for ellipsoidal pattern compared with the circular pattern because of wear debris and lubricant getting trapped.

关键词： laser surface micro texturing AIsI52100 3D surface roughness wear scanning electron microscopy

Genetics provides new individualized therapeutic targets for Parkinson’s disease

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Neural Regeneration Research 2021年第5期16卷 994-995页

作者： Eric joshua Garcia Ellen sidransky Medical Genetics Branch National Human Genome Research InstituteNational Institutes of HealthBethesdaMDUSA

The identification of genes increasing one’s risk of developing common,complex disorders like Parkinson’s disease(PD)can provide novel therapeutic opportunities.A prime example of this are the consequences of mutations in GBA1,the gene responsible for the lysosomal storage disorder Gaucher disease(GD).GD is a multi-system disorder,primarily affecting tissues of the reticuloendothelial system.A subset of patients with GD also have neuronopathic manifestations(types 2 and 3 GD).

关键词： therapeutic consequences primarily