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Wildfire severity alters soil microbial exoenzyme production and fungal abundances in the southern Appalachian Mountains

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Pedosphere 2024年第5期34卷 865-878页

作者： Megan l.SCHIll Richard BAIRD Shawn P.BROWN allison M.VEACH Department of Integrative Biology University of Texas at San Antonio Biochemistry Molecular Biology Entomology and Plant Pathology Department Mississippi State University Department of Biological Sciences The University of Memphis

Climate change has increased drought frequency and duration that are exacerbated by increased temperatures globally. This effect has, and will continue,to increase fire occurrence across many regions of North America. In the southern Appalachian Mountains, wildfires with high burn severity occurred in 2016due to increased drought and human activity. To investigate the effects of burn severity on soil physicochemical properties, microbial extracellular enzyme production, and microbial abundances in a temperate region, surface soils (0–15 cm) were collected from two sites (the Great Smoky Mountains National Park in Tennessee and the Nantahala National Forest in North Carolina, USA) spanning lightly, moderately, and severely burned areas, accompanied by adjacent unburned locations that act as controls. The soil samples were collected at three time points between 2017 and 2019 (i.e., 0.5, 1, and 2.5 years post-fire)among burn severity plots. Total hydrolytic enzyme production varied over time, with severe burn plots having significantly lower enzyme production at 2.5years post-fire. Individual enzymes varied among burn severities and across time post-fire. light burn plots showed greater carbon-specific (β-glucosidase and β-xylosidase) and phosphorus-specific (acid phosphatase) enzyme activities at 0.5 years post-fire, but this effect was transient. At 2.5 years post-fire, theβ-xylosidase and acid phosphatase activities were lower in severe or moderate burn plots relative to the controls. In contrast, the activity of nitrogen-specific enzyme leucyl aminopeptidase was the lowest in severe burn plots at 0.5 years post-fire, but was the lowest in light burn plots at 2.5 years post-fire. The fungi:bacteria ratio declined with burn severity, indicating that fungi are sensitive or less resilient to high burn severity during recovery. These results suggest that wildfires alter trajectories for soil microbial structure and function within a 2.5-year timeframe, which potentially

关键词： 16S rRNA burn severity extracellular enzyme fungi:bacteria ratio internal transcribed spacer microbial structure

Evaluating information-seeking approaches to metacognition

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Current Zoology 2011年第4期57卷 531-542页

作者： Jonathon D. CRYSTAl allison l. FOOTE Department of Psychological and Brain Sciences Indiana University Bloomington IN 47405 USA Department of Psychology University of Georgia Athens GA 30602 USA

Metacognition has been divided into information monitoring and control processes. Monitoring involves knowing that you know or do not know some information without taking corrective action. Control involves taking corrective action based on the knowledge that you know or do not know some information. In comparative metacognition, considerable attention has been paid toward critically assessing putative evidence for information monitoring in non-human animals. However, less attention has been paid toward critically evaluating evidence for control processes in animals. We briefly review a critique of information-monitoring in animals. Next, we apply these concepts to a number of studies that focus on information seeking in animals. The main type of evidence for control processes in animals come from tube tipping experiments. Before having the opportunity to search for the bait in these experiments, the subject sometimes observes opaque tubes being baited but is sometimes prevented from seeing the baiting. The observations that the subjects look more if baiting was not seen and are more accurate if baiting was seen have been taken as evidence for metacognition in information-seeking experiments. We propose simple alternative hypotheses that are sufficient to explain putative evidence for information seeking in animals without positing metacognition. The alternative explanation focuses on two relatively simple principles： First, an animal has a default ＂look before you go＂ response which supersedes random searches in space. Second, spatially guided behavior follows a default rule of ＂go where something good is.＂ These principles can explain the results of tube tipping experiments without proposing metacognition [Current Zoology 57 （4）： 531-542, 2011].

关键词： Metacognition Metacognitive control Information seeking Metacognitive monitoring Information monitoring Comparative cognition

A precise monitoring of snow surface height in the region of lambert Glacier basin-Amery Ice Shelf,East Antarctica

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Science China Earth Sciences 2005年第1期48卷 100-111页

作者： I.allison Australian Antarctic Division and Antarctic Climate and Ecosystems CRC

The net surface snow accumulation on the Antarctic ice sheet is determined by a combination of precipitation, sublimation and wind redistribution. We present a one-year record of hourly snow-height measurements at lGB69 (70°50'S, 77°04'E, 1850 m a.s.l.). east side of lambert Glacier basin (lGB), and 4 year record at G3 (70°53'S, 69°52'E, 84 m a.s.l.), Amery Ice Shelf (AIS). The measurements were made with ultrasonic sensors mounted on automatic weather stations installed at two sites. The snow accumulation at lGB69 is approximately 70 cm. Throughout the winter, between April and September, there was little change in surface snow height (SSH) at the two sites. The negative SSH change is due to densification at lGB69, and is due to both ablation and densification at G3. The strongest accumulation at two sites occurred during the period between October and March (accounting for 101.6% at lGB69), with four episodic increasing events occurring during 2002 for lGB69, and eight events during 1999-2002 for G3 (2 to 3 events per year). At lGB69, these episodic events coincided with obvious humidity 'pulses' and decreases of incoming solar radiation as recorded by the AWS. Observations of the total cloud amount at Davis station, 160 km NNE of lGB69, showed good correlation with major accumulation events recorded at lGB69. There was an obvious anti-correlation between the lowest cloud height at Davis and the daily accumulation rate at lGB69. Although there was no correlation over the total year between wind speed and accumulation at lGB69, large individual accumulation events are associated with episodes of strong wind (>7 m/s), we estimate drift snow may contribute to total SSH up to 35%. Strong accumulation events at lGB69 are associated with major storms in the region and inland transport of moist air masses from the coast.

关键词： Antarctica, lambert Glacier basin, Amery Ice Shelf, accumulation, katabatic wind.

Knee osteoarthritis:Therapeutic alternatives in primary care

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World Journal of Orthopedics 2017年第2期8卷 187-191页

作者： allison l Evaniew Nathan Evaniew Division of Orthopaedics Department of SurgeryMcMaster University

AIM To discusses pharmacological and non-pharmacological therapeutic alternatives for managing knee osteoarthritis in primary care by primary health care nurse *** A case example is presented, the evidence-based guideline recommendations of the Osteoarthritis Research Society International and the American Academy of Orthopaedic Surgeons are reviewed, and a plan of care is *** Osteoarthritis is the most common form of arthritis seen in primary care, and it is a major public health issue because the aging population and widespread obesity have drastically increased incidence. Osteoarthritis is clinically associated with escalating chronic pain, physical disability, and decreased quality of life. Early diagnosis of mild osteoarthritis in relatively young patients presents an opportunity for primary health care providers to manage pain, increase quality of life, and decrease risk of disability. CONClUSION Primary health care providers can implement these recommendations in their own practices to provide care to patients with knee osteoarthritis based on current best evidence.

关键词： Osteoarthritis Knee Primary care Nurse practitioner Guidelines

Transient occult cardiotoxicity in children receiving continuous beta-agonist therapy

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World Journal of Pediatrics 2014年第4期10卷 324-329页

作者： Christopher l Carroll Melinda Coro allison Cowl Kathleen A Sala Craig M Schramm Department of Pediatrics Connecticut Children's Medical CenterHartfordCTUSA

Background:Continuous beta-agonist therapy,typically in the form of inhaled albuterol,is the first line therapy for the treatment of acute and severe bronchospasm in *** this treatment is commonly used,concerns about cardiotoxicity have been *** aimed to investigate the cardiotoxic effects of continuous beta-agonist therapy in ***:We conducted a retrospective review of children admitted to the intensive care unit(ICU)between May 2008 and April 2009,who were treated with continuous beta-agonist therapy(intravenous and nebulized).Results:Twenty of the 36 children treated with continuous albuterol had repeated serum troponin-T and lactate levels *** patients(55%)were also treated with continuous intravenous *** levels of troponin-T levels were found in 25%of children,and elevated lactate levels were found in 60%.However,all returned to normal levels within 48 hours of ICU admission,despite continued beta-agonist *** children experienced arrhythmias during *** was no association between intravenous terbutaline use and elevated troponin-T[odds ratio(OR),1.3;95%CI,0.2-10.3]or with elevated serum lactate(OR,0.6;95%CI,0.1-3.7).There was also no association between elevated troponin-T or lactate and ICU or hospital length of ***:In this small study,a significant proportion of children had elevated serum troponin-T and lactate levels while receiving inhaled continuous beta-agonist therapy,irrespective of intravenous ***,these abnormal values all returned to normal within 48 hours of ICU admission and were not associated with increased duration of hospitalization.

关键词： asthma beta-agonist pediatric

PRISMS-Fatigue computational framework for fatigue analysis in polycrystalline metals and alloys

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npj Computational Materials 2021年第1期7卷 349-360页

作者： Mohammadreza Yaghoobi Krzysztof S.Stopka Aaditya lakshmanan Veera Sundararaghavan John E.allison David l.McDowell Materials Science and Engineering University of MichiganAnn ArborMIUSA Woodruff School of Mechanical Engineering Georgia Institute of TechnologyAtlantaGAUSA Aerospace Engineering University of MichiganAnn ArborMIUSA School of Materials Science and Engineering Georgia Institute of TechnologyAtlantaGAUSA

The PRISMS-Fatigue open-source framework for simulation-based analysis of microstructural influences on fatigue resistance for polycrystalline metals and alloys is presented *** framework uses the crystal plasticity finite element method as its microstructure analysis tool and provides a highly efficient,scalable,flexible,and easy-to-use ICME community *** PRISMS-Fatigue framework is linked to different open-source software to instantiate microstructures,compute the material response,and assess fatigue indicator *** performance of PRISMS-Fatigue is benchmarked against a similar framework implemented using *** indicate that the multilevel parallelism scheme of PRISMS-Fatigue is more efficient and scalable than ABAQUS for large-scale fatigue *** performance and flexibility of this framework is demonstrated with various examples that assess the driving force for fatigue crack formation of microstructures with different crystallographic textures,grain morphologies,and grain numbers,and under different multiaxial strain states,strain magnitudes,and boundary conditions.

关键词： fatigue alloys grain

An overview of the role of neutrophils in innate immunity,inflammation and host-biomaterial integration

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Regenerative Biomaterials 2017年第1期4卷 55-68页

作者： Gretchen S.Selders allison E.Fetz Marko Z.Radic Gary l.Bowlin Department of Biomedical Engineering University of MemphisMemphisTNUSA Department of Microbiology Immunology and BiochemistryUniversity of Tennessee Health Science Center(UTHSC)MemphisTN 38163USA

Despite considerable recent progress in defining neutrophil functions and behaviors in tissue repair,much remains to be determined with regards to its overall role in the tissue integration of *** article provides an overview of the neutrophil’s numerous,important roles in both inflammation and resolution,and subsequently,their role in biomaterial *** function in three primary capacities:generation of oxidative bursts,release of granules and formation of neutrophil extracellular traps(NETs);these combined functions enable neutrophil involvement in inflammation,macrophage recruitment,M2 macrophage differentiation,resolution of inflammation,angiogenesis,tumor formation and immune system *** exhibit great flexibility to adjust to the prevalent microenvironmental conditions in the tissue;thus,the biomaterial composition and fabrication will potentially influence neutrophil behavior following *** review serves to highlight the neutrophil’s plasticity,reiterating that neutrophils are not just simple suicidal killers,but the true maestros of resolution and regeneration.

关键词： neutrophil tissue engineering NETosis tissue regeneration host response inflammation

Study of Aerosol Direct and Indirect Effects and Auto-conversion Processes over the West African Monsoon Region Using a Regional Climate Model

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Advances in Atmospheric Sciences 2018年第2期35卷 182-194页

作者： Zeinab SAlAH Ahmed SHAlABY allison l. STEINER Ashraf S. ZAKEY Ritesh GAUTAM Mohamed M. ABDEl WAHAB The Egyptian Meteorological Authority Cairo 11784 Egypt University of Michigan Department of Climate and Space Sciences and Engineering Ann Arbor M148109-2143 USA Centre of Studies in Resources Engineering and Interdisciplinary Program in Climate Studies Indian Institute of Technology Bombay Bombay 400076 India Cairo University Department of Astronomy Space Science and Meteorology Giza 12613 Egypt Environmental Defense Fund Washington DC 20009 USA

This study assesses the direct and indirect effects of natural and anthropogenic aerosols （e.g., black carbon and sulfate） over West and Central Africa during the West African monsoon （WAM） period （June-July-August）. We investigate the impacts of aerosols on the amount of cloudiness, the influences on the precipitation efficiency of clouds, and the associated radiative forcing （direct and indirect）. Our study includes the implementation of three new formulations of auto-conversion parameterization [namely, the Beheng （BH）, Tripoli and Cotton （TC） and liu and Daum （R6） schemes] in RegCM4.4.1, besides the default model＇s auto-conversion scheme （Kessler）. Among the new schemes, BH reduces the precipitation wet bias by more than 50% over West Africa and achieves a bias reduction of around 25% over Central Africa. Results from detailed sensitivity experiments suggest a significant path forward in terms of addressing the long-standing issue of the characteristic wet bias in RegCM. In terms of aerosol-induced radiative forcing, the impact of the various schemes is found to vary considerably （ranging from -5 to -25 W m-2）.

关键词： aerosol, cloud West African monsoon auto-conversion RegCM

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时钟与电网

科技纵览 2024年第3期 78-78页

作者： allison Marsh 不详

1916年10月23日,位名叫亨利·E.沃伦(Henry ***)的工程师在位于波士顿的爱迪生电气照明公司的l街发电站安装了一台电钟,悄然间彻底改变了电力传输。这个主站时钟保持了一种非常特殊的时间类型,它结合使用了同步自启动电机和钟摆来将发... 详细信息

1916年10月23日,位名叫亨利·E.沃伦(Henry ***)的工程师在位于波士顿的爱迪生电气照明公司的l街发电站安装了一台电钟,悄然间彻底改变了电力传输。这个主站时钟保持了一种非常特殊的时间类型,它结合使用了同步自启动电机和钟摆来将发电站的交流电稳定地保持在每秒60个周期的频率。随着越来越多的发电站采用电钟,频率调节让它们得以共享电力并建立一个相互连接的电网。直到20世纪40年代末,沃伦电钟公司的站钟管理着美国95%以上的电力线路。

关键词：电气照明电力线路电力传输发电站频率调节启动电机交流电爱迪生