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Submaximal oxygen uptake kinetics, functional mobility, and physical activity in older adults with heart failure and reduced ejection fraction

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Journal of Geriatric Cardiology 2016年第5期13卷 450-457页

作者： Scott L Hummel john Herald Craig Alpert Kimberlee A Gretebeck Wendy S Champoux Donald r Dengel Peter V Vaitkevicius Neil B Alexander Department of lnternal Medicine University of Michigan Ann Arbor MI USA VA Ann Arbor Healthcare System Ann Arbor MI USA School of Nursing University of Wisconsin-Madison Madison WI USA William Beaumont School of Medicine Oakland University Royal Oak MI USA School of Kinesiology University of Minnesota Minneapolis MN USA Aspirus Health System Ontanagon ML USA

Background Submaximal oxygen uptake measures are more feasible and may better predict clinical cardiac outcomes than maximal tests in older adults with heart failure （HF）. We examined relationships between maximal oxygen uptake, submaximal oxygen kinetics, fianctional mobility, and physical activity in older adults with HF and reduced ejection fraction. Methods Older adults with HF and reduced ejection fraction （n = 25, age 75 ：i： 7 years） were compared to 25 healthy ageand gender-matched controls. Assessments included a maximal treadmill test for peak oxygen uptake （VO2p^ak）, oxygen uptake kinetics at onset of and on recovery from a submaximal treadmill test, functional mobility testing [Get Up and Go （GUG）, Comfortable Gait Speed （CGS）, Unipedal Stance （US）], and self-reported physical activity （PA）. results Compared to controls, HF had worse performance on GUG, CGS, and US, greater delays in submaximal oxygen uptake kinetics, and lower PA. In controls, VO2peak was more strongly associated with functional mobility and PA than submaximal oxygen uptake kinetics. In HF patients, submaximal oxygen uptake kinetics were similarly associated with GUG and CGS as VO2peak, but weakly associated with PA. Conclusions Based on their mobility performance, older HF patients with reduced ejection fraction are at risk for adverse functional outcomes. In this population, submaximal oxygen uptake measures may be equivalent to VO2 peak in predicting functional mobility, and in addition to being more feasible, may provide better insight into how aerobic function relates to mobility in older adults with HF.

关键词： Aging Congestive heart failure Mobility Oxygen uptake The elderly

Femtosecond laser-assisted astigmatic keratotomy: a review

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Eye and Vision 2018年第1期5卷 59-69页

作者： john S.M.Chang Department of Ophthalmology Hong Kong Sanatorium&Hospital8/FLi Shu Pui BlockPhase II2 Village RoadHappy ValleyHong KongChina

Background:Astigmatic keratotomy(ak)remains an accessible means to correct surgically induced or naturally occurring *** advantages of femtosecond laser-assisted astigmatic keratotomy(FSak)over conventional methods have been recognized *** text:This review evaluates the efficacy,complications,and different methods of FSak for correction of astigmatism in native eyes and those that underwent previous penetrating keratoplasty(PKP).The penetrating and intrastromal FSak(IFSak)techniques can reduce post-keratoplasty astigmatism by 35.4%to 84.77%and 23.53%to 89.42%,*** native eyes,the penetrating and IFSak techniques reduce astigmatism by 26.8%to 58.62%and 36.3%to 58%respectively,implying that the magnitude of the astigmatic reduction is comparable between the two FSak ***,IFSak offers the additional advantages of almost no risk of infection,wound gape,and epithelial *** use of nomograms,anterior-segment optical coherence tomography,and consideration of posterior cornea and corneal biomechanics are helpful to enhance the efficacy and safety of *** complications of FSak in eyes that underwent PKP include overcorrection,visual loss,microperforations,infectious keratitis,allograft rejection,and *** reported difficulties in native eyes include overcorrection,anterior gas br.akthrough,and suction ***:In eyes that underwent PKP,FSak effectively reduces high regular or irregular astigmatism,with rare and manageable ***,the drawbacks of the procedure include the potential loss of visual acuity and low *** native eyes undergoing femtosecond laser-assisted cataract surgery,IFSak is a good choice to correct low astigmatism(rs).The refractive effect of astigmatism from the posterior cornea needs to be considered in the nomograms for native eyes undergoing refractive cataract *** further improve the efficacy of FSak,more large-scale ra

关键词： Femtosecond laser-assisted astigmatic keratotomy Post-keratoplasty astigmatism Astigmatism correction refractive surgery

Host-environment mismatches associated with subalpine fir decline in Colorado

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Journal of Forestry research 2016年第5期27卷 1177-1189页

作者： robin M. reich john E. Lundquist Kristina Hughes Colorado State University Fort Collins CO USA U.S. Forest Service Anchorage Anchorage AK 99501 USA

Subalpine fir decline （SFD） has killed more trees in Colorado＇s high elevation forests than any other insect or disease problem. The widespread nature of this disorder suggests that the cause involves climatic factors. We examined the influence of varying combinations of average annual temperature and precipitation on the incidence and distribution of SFD. Climatic transition matrices generated in this study indicate that most healthy trees are found in climatic zones with moderate to low temperatures and high precipitation; whereas, SFD occurs mostly in zones of moderate temperatures and moderate precipitation. The contrasting distributions define an environmental mismatch. Forests matched with favorable climatic conditions thrive; those that are mismatched can become vulnerable to decline disease.

关键词： Abiotic disorder Climate stress High elevation forests Forest disease - Subalpine fir

Flood Forecasting GIS Water-Flow Visualization Enhancement (WaVE): A Case Study

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Journal of Geographic Information System 2016年第6期8卷 692-728页

作者： Timothy r. Petty Nawajish Noman Deng Ding john B. Gongwer Department of Civil and Environmental Engineering University of Alaska Fairbanks Fairbanks AK USA Esri Redlands CA USA iCatalyst Washington DC USA

riverine flood event situation awareness and emergency management decision support systems require accurate and scalable geoanalytic data at the local level. This paper introduces the Water-flow Visualization Enhancement (WaVE), a new framework and toolset that integrates enhanced geospatial analytics visualization (common operating picture) and decision support modular tools. WaVE enables users to: 1) dynamically generate on-the-fly, highly granular and interactive geovisual real-time and predictive flood maps that can be scaled down to show discharge, inundation, water velocity, and ancillary geomorphology and hydrology data from the national level to regional and local level;2) integrate data and model analysis results from multiple sources;3) utilize machine learning correlation indexing to interpolate streamflow proxy estimates for non-functioning streamgages and extrapolate discharge estimates for ungaged streams;and 4) have time-scaled drill-down visualization of real-time and forecasted flood events. Four case studies were conducted to test and validate WaVE under diverse conditions at national, regional and local levels. results from these case studies highlight some of WaVE’s inherent strengths, limitations, and the need for further development. WaVE has the potential for being utilized on a wider basis at the local level as data become available and models are validated for converting satellite images and data records from remote sensing technologies into accurate streamflow estimates and higher resolution digital elevation models.

关键词： Geovisualization riverine Flooding Geoanalytics Forecasting Machine Learning Emergency Management Decision Support

Investigation of normal,lateral,and oblique impact of microscale projectiles into unidirectional glass/epoxy composites

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Defence Technology（防务技术） 2022年第11期18卷 1960-1978页

作者： Christopher S.Meyer Isabel G.Catugas john W.Gillespie Jr. Bazle Z.Gama Haque University of Delaware Center for Composite Materials(UD-CCM) 101 Academy StreetNewarkDE19716USA

Spacesuits and spacecraft must endure high velocity impacts from micrometeoroids. This work considers the impact of 100 μm diameter projectiles into composite targets at velocities from 0.5 km/s to 2 km/*** work begins by presenting an energy-based theoretical model relating depth of penetration(Do P)and impact force to impact velocity, characteristic time, and threshold velocity and force. Next, this work compares numerical simulations of normal impact on composites to the theoretical model. Numerical simulations are conducted with LS-DYNA and the well-known composite model, MAT-162. The numerical models consider unidirectional S2-glass fiber reinforced SC-15 epoxy composite laminates. The numerical model shows good correlation with the theoretical model. The numerical model also investigates lateral impact, parallel to the fiber direction, and oblique impact at angles from 30°to 82.5°.This work decomposes oblique impact into normal and lateral components, and compares them with normal and lateral impact results. The results show good correlation of the normal component of oblique results with the theoretical model. This numerical and theoretical study focuses on Do P, velocity, and penetration resistance force as functions of time. The theoretical model and numerical simulations are used to determine new Do P parameters: characteristic time of depth of penetration and threshold impact velocity. These models are a first step in developing the capability to predict Do P for oblique,microscale, high-speed impact on composite materials.

关键词： Microscale Hypervelocity impact Composites Erosion Penetration

reimagining large river management using the resist-Accept-Direct(rAD)framework in the Upper Mississippi river

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Ecological Processes 2023年第1期12卷 645-664页

作者： Nicole K.Ward Abigail J.Lynch Erik A.Beever Joshua Booker Kristen L.Bouska Holly Embke Jeffrey N.Houser john F.Kocik Joshua Kocik David J.Lawrence Mary Grace Lemon Doug Limpinsel Madeline r.Magee Bryan M.Maitland Owen McKenna Andrew Meier john M.Morton Jeffrey D.Muehlbauer robert Newman Devon C.Oliver Heidi M.rantala Greg G.Sass Aaron Shultz Laura M.Thompson Jennifer L.Wilkening Minnesota Department of Natural resources Lake CityMN 55041USA U.S.Geological Survey National Climate Adaptation Science CenterRestonVA 22041USA U.S.Geological Survey Northern Rocky Mountain Science CenterBozemanMT 59715USA Department of Ecology Montana State UniversityBozemanMT 59715USA U.S.Fish and Wildlife Service National Wildlife Refuge SystemOak HarborOH 43449USA U.S.Geological Survey Upper Midwest Environmental Sciences CenterLa CrosseWI 54603USA U.S.Geological Survey Midwest Climate Adaptation Science CenterSt.PaulMN 55108USA NOAA NEFSC OronoME 04473USA University of Nebraska-Lincoln LincolnNE 68503USA National Park Service Climate Change Response ProgramFort CollinsCO 80525USA U.S.Fish and Wild-life Service National Wildlife Refuge SystemBloomingtonMN 55437USA Habitat Conservation Division NOAAAlaska RegionAnchorageAK 99513USA Wisconsin Department of Natural resources MadisonWI 53703USA Aquatic Sciences Center Center for LimnologyUW-MadisonMadisonWI 53706USA U.S.Geological Survey Northern Prairie Wildlife Research Center and Midwest Climate Adaptation Science CenterJamestownND 58401USA U.S.Army Corps of Engineers La CrescentMN 55947USA Alaska Wildlife Alliance AnchorageAK 99520USA U.S.Geological Survey Alaska Cooperative Fish and Wildlife Research UnitUniversity of Alaska FairbanksFairbanksAK 99775USA University of North Dakota Grand ForksND 58202USA Minnesota Department of Natural resources DuluthMN 55804USA Wisconsin Department of Natural resources Boulder JunctionWI 54512USA Great Lakes Indian Fish and Wildlife Commission(GLIFWC) OdanahWI 54861USA U.S.Geological Survey National Climate Adaptation Science Centerand School of Natural ResourcesUniversity of TennesseeKnoxvilleTN 37996USA U.S.Fish and Wildlife Service National Wildlife Refuge SystemFort CollinsCO 80526USA

Background Large-river decision-makers are charged with maintaining diverse ecosystem services through unprec-edented social-ecological transformations as climate change and other global stressors *** interconnected,dendritic habitats of rivers,which often demarcate jurisdictional boundaries,generate complex management ***,we explore how the resist–Accept–Direct(rAD)framework may enhance large-river management by promoting coordinated and deliberate responses to social-ecological trajectories of *** rAD frame-work identifies the full decision space of potential management approaches,wherein managers may resist change to maintain historical conditions,accept change toward different conditions,or direct change to a specified future with novel *** the Upper Mississippi river System,managers are facing social-ecological transformations from more frequent and extreme high-water *** illustrate how rAD-informed basin-,reach-,and site-scale decisions could:(1)provide cross-spatial scale framing;(2)open the entire decision space of potential management approaches;and(3)enhance coordinated inter-jurisdictional management in response to the trajectory of the Upper Mississippi river *** The rAD framework helps identify plausible long-term trajectories in different reaches(or subbasins)of the river and how the associated social-ecological transformations could be managed by altering site-scale *** reach-scale objectives may reprioritize how,where,and when site conditions could be altered to contribute to the basin goal,given the basin’s plausible trajectories of change(e.g.,by coordinating action across sites to alter habitat connectivity,diversity,and redundancy in the river mosaic).Conclusions When faced with long-term systemic transformations(e.g.,>50 years),the rAD framework helps explicitly consider whether or when the basin vision or goals may no longer be achievable,and direct options may open y

关键词： Ecosystem Management Transformation Social-ecological system Anthropocene Climate change Basin planning Cross-scale interactions

中国西部天山高山带冷生土壤及相关土壤的地貌发生学(英)

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冰川冻土 2002年第5期24卷 517-522页

作者： PIHG Chien\|lu~ 1,\ ZHAO Lin ~ 2,\ WAng Shao\|ling ~ 2,\ ronald Paetzold~ 3, john Kimble~ 3,\ YE Bai\|sheng ~ 2 (1.Palmer research Center, University of Alaska Fairbanks, Palmer, ak 99645, USA 2.CArEErI, Chinese Academy of Sciences, Lanzhou Ga Palmer research Center University of Alaska Fairbanks 美国 Palmer CArEErI Chinese Academy of Sciences 甘肃 Lanzhou 730000 National Soil Survey Center USDA - USDA - NRCS 美国 Lincoln

The soil landscape relationship was investigated in the Upper Urumqi river Basin of the Tienshan Mountain range, Xinjiang, China. Cryosols occurred in glaciated valleys and north\|facing toeslopes at elevations above \{3 000\} m. Most cryosols developed in moraine are Aquiturbels. The microrelief is dominated by earth hummocks, thus the surface organic layers are either discontinuous or broken due to frost action. The Bg horizons are either gleyed or mottled and frost\|churned organic matter is common in the lower Bg horizons. Stratified horizons and buried organic or A horizons are also common on gentle sloping or undulating moraines indicating the effects of gelifluction. reticular structures formed in the lower active layers due to ice lens formation and freeze\|thaw cycles. The active layer thickness ranges from 140～200 cm. The organic cryosols (Hemistels) occur in depressions and north\|facing toeslopes with an active layer thickness ranging from 90～110 cm. Soils formed on south\|facing slopes have a mollic epipedon 20～25 cm thick and a strong brown cambic horizon and are classified as Haplocryolls. The distribution of cryosols is smaller as compared with the extent of permafrost due to the depth requirement of permafrost in cryosol classification. However, the existence of permafrost at greater depth cannot be ignored in land use interpretations.

关键词：中国天山高山带冷生土壤地貌发生学

Climatological Characteristics of Historical and Future High-Wind Events in Alaska

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Atmospheric and Climate Sciences 2018年第4期8卷 373-394页

作者： Soumik Basu john E. Walsh International Arctic research Center University of Alaska Fairbanks AK USA

High winds cause waves, storm surge, erosion and physical damage to infrastructure and ecosystems. However, there have been few evaluations of wind climatologies and future changes, especially change in high-wind events, on a regional basis. This study uses Alaska as a regional case study of climatological wind speed and direction. Eleven first-order stations across different subregions of Alaska provide historical data (1975-2005) for the observational climatology and for the calibration of Coupled Model Inter comparison Project (CMIP5) simulations, which in turn provide projections of changes in winds through 2100. Historically, winds exceeding 25 and 35 knots are most common in the Bering Sea coastal region of Alaska, followed by northern Alaska coastal areas. Autumn and winter are the seasons of most frequent high-wind occurrences in the coastal sites, while there is no distinct seasonal peak at the interior stations where high-wind events are less frequent. An examination of the sea level pressure pattern associated with the highest-wind event at each station reveals the presence of a strong pressure gradient associated with an extratropical cyclone in most cases. Northern coastal regions of Alaska are projected to experience increased frequencies of high-wind events during the cold season, especially late autumn and early winter, when reduced sea ice cover in the late century will leave coastal regions increasingly vulnerable to flooding and erosion.

关键词： Extreme Winds Station Data CMIP5 Wind Climatology Alaskan Climate

Near-Surface Wind-Speed Stilling in Alaska during 1984-2016 and Its Impact on the Sustainability of Wind Power

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Journal of Power and Energy Engineering 2019年第7期7卷 71-124页

作者： Gerhard Kramm Nicole Molders john Cooney ralph Dlugi Engineering Meteorology Consulting Fairbanks AK USA Department of Atmospheric Sciences and Geophysical Institute University of Alaska Fairbanks Fairbanks AK USA Department of Atmospheric Sciences Texas A&M University College Station TX USA Arbeitsgruppe Atmospharische Prozesse (AGAP) Munich Germany

Based on wind-speed records of Alaska’s 19 first-order weather stations, we analyzed the near-surface wind-speed stilling for January 1, 1984 to December 31, 2016. With exception of Big Delta that indicates an increase of 0.0157 m·s–1·a–1, on average, all other first-order weather stations show declining trends in the near-surface wind speeds. In most cases, the average trends are less then?–0.0300?m·s–1·a–1. The strongest average trend of?–0.0500?m·s–1·a–1 occurred at Homer, followed by?–0.0492?m·s–1·a–1 at Bettles, and?–0.0453?m·s–1·a–1 at Yakutat, while the declining trend at Barrow is marginal. The impact of the near-surface wind-speed stilling on the wind-power potential expressed by the wind-power density was predicted and compared with the wind-power classification of the National renewable Energy Laboratory and the Alaska Energy Authority. This wind-power potential is, however, of subordinate importance because wind turbines only extract a fraction of the kinetic energy from the wind field characterized by the power efficiency. Since wind turbine technology has notably improved during the past 35 years, we hypothetically used seven currently available wind turbines of different rated power and three different shear exponents to assess the wind-power sustainability under changing wind regimes. The shear exponents 1/10, 1/7, and 1/5 served to examine the range of wind power for various conditions of thermal stratification. Based on our analysis for January 1, 1984 to December 31, 2016, Cold Bay, St. Paul Island, Kotzebue, and Bethel would be very good candidates for wind farms. To quantify the impact of a changing wind regime on wind-power sustainability, we predicted wind power for the periods January 1, 1984 to December 31, 1994 and January 1, 2006 to December 31, 2016 as well. Besides Big Delta that suggests an increase in wind power of up to 12% for 1/7, predicted wind power decreased at all sites with the highest decline at Annette (≈38%), Kodiak (≈30%),

关键词： Near-Surface Wind Speed Wind Power Wind-Power Potential Wind-Power Density Wind-Speed Stilling Energy Flux Budget Sensible and Latent Heat