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Spread of common native and invasive grasses and ruderal trees following anthropogenic disturbances in a tropical dry forest

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Ecological Processes 2017年第1期6卷 394-407页

作者： Xavier A.Jaime Skip J.Van Bloem frank h.koch Stacy A.C.Nelson Department of Ecosystem Science and Management Texas A&M University2138 TAMUCollege StationTX 77843-2138USA Belle W.Baruch Institute of Coastal Ecology and Forest Science Clemson UniversityPO Box 596GeorgetownSC 29442USA USDA Forest Service Southern Research Station3041 East Cornwallis RoadResearch Triangle ParkNC 27709USA Center for Geospatial Analytics Department of Forestry and Environmental ResourcesNorth Carolina State UniversityRaleighNC 27695USA.

Introduction:A fundamental challenge to the integrity of tropical dry forest ecosystems is the invasion of nonnative grass *** grasses compete for resources and fuel anthropogenic *** 2012,a bulldozer from the Puerto Rico Electric Power Authority cleared a 570-m trail from a state road into a mature dry forest section of Guánica Forest to control a *** monitored colonization by a non-native invasive grass(Megathyrsus maximus),a highly invasive tree(Leucaena leucocephala),and a native grass(Uniola virgata),as well as natural regeneration,along the bulldozer *** determined whether bulldozing facilitated colonization by these species into the forest and the extent of ***:Distance from propagule source and temporal variations strongly influenced colonization by our three focal *** maximus invaded along the trail from source populations by the state *** establishment of new colonies of *** seedlings went as far as 570 m inside the forest(i.e.,at the end of the bulldozer trail),but we found most new colonies within 270 m of the *** leucocephala exhibited a similar spreading *** disturbance,Uniola virgata was distributed widely across the forest,but the highest densities were found in areas near the latter portion(>401 m)of the bulldozer ***,the species formed new clumps along more than half of the trail(250 to 570 m),apparently colonizing from undisturbed patches ***:Bulldozing facilitated the invasion of non-native *** projected community assemblage will be more fire-prone than before since *** carries fire across the landscape better than ***,emphasizing the capacity of invasive plant colonization to alter local ecological processes after only a single wildfire and bulldoze *** results provide a valuable baseline for short-term vegetation response to anthropogenic disturbances in tropical semi-deciduous dry forests.

关键词： Tropical dry forest Grass invasions Bulldozing Wildfire Leucaena leucocephala Megathyrsus(Panicum)maximus Uniola virgata

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Meta-analysis of laparoscopic vs open cholecystectomy in elderly patients

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World Journal of Gastroenterology 2014年第46期20卷 17626-17634页

作者： Stavros A Antoniou George A Antoniou Oliver O koch Rudolph Pointner frank A Granderath Center for Minimally Invasive Surgery Hospital Neuwerk41066 M?nchengladbachGermany Department of General Surgery University General Hospital of Heraklion71500 CreteGreece Department of Vascular Surgery Red Cross Hospital11526 AthensGreece Department of General and Visceral Surgery Sisters of Charity Hospital4020 LinzAustria Department of General and Visceral Surgery Hospital Zell am See5700 Zell am SeeAustria

AIM:To investigate the comparative effect of laparoscopic and open cholecystectomy in elderly ***:Laparoscopic cholecystectomy has induced a revolution in the treatment of gallbladder ***,surgeons have been reluctant to implement the concepts of minimally invasive surgery in older patients.A systematic review of Medline was embarked on,up to June *** which provided outcome data on patients aged 65 years or older,subjected to laparoscopic or open cholecystectomy were ***,morbidity,cardiac and pulmonary complications were the outcome measures of treatment *** methodological quality of selected studies was appraised using valid assessment tools.Τhe random-effects model was applied to synthesize outcome ***:Out of a total of 337 records,thirteen articles(2 randomized and 11 observational studies)reporting on the outcome of 101559 patients(48195in the laparoscopic and 53364 in the open treatment group,respectively)were *** ratios(OR)were constantly in favor of laparoscopic surgery,in terms of mortality(1.0%vs 4.4%,OR=0.24,95%CI:0.17-0.35,Phe laparoscopic concept,when adjusted for age and co-morbid ***:Further high-quality evidence is necessary to draw definite conclusions,although bestavailable evidence supports the selective use of laparoscopy in this patient population.

关键词： Laparoscopic Open cholecystectomy Surgery Elderly Older Geriatric Complications Mortality Morbidity

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Efficacy of chlorfenapyr against adult Tribolium castaneum exposed on concrete＂ effects of exposure interval, concentration and the presence of a food source after exposure

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Insect Science 2009年第2期16卷 157-163页

作者： frank h. Arthur USDA-ARS Grain Marketing and Production Research Center Manhattan Kansas USA

Chlorfenapyr, an insecticidal pyrrole, was applied to concrete arenas at concentrations of 1. 1, 0.825, 0.55, and 0.275 g of active ingredient [AI]/m^2. Adult Tribolium castaneum （herbst）, the red flour beetle, were exposed for 2, 4, or 8 h at each concentration, then removed and held either with or without food （wheat flour） for 7 days. Survival was assessed when the beetles were removed fi＇om the exposure arenas and daily during the post- exposure period. In the presence of food, survival was high regardless of concentration and the day on which post-treatment survival was assessed, but survival did decrease as the exposure period increased from 4 to 8 h. When the beetles were not given food after exposure, survival at each concentration and exposure period declined during the 1-week post- exposure assessments. This pattern of decrease could be described by linear and non-linear equations. Results show the presence of food material greatly compromised effectiveness of the insecticide, and emphasize the importance of cleaning and sanitation in conjunction with insecticide treatments.

关键词： chlorfenapyr efficacy sanitation Tribolium castaneum

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Aerosol distribution and efficacy in a commercial food warehouse

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Insect Science 2008年第2期15卷 133-140页

作者： frank h. Arthur USDA-ARS Grain Marketing and Production Research Center Manhattan Kansas USA

A series of field trials were conducted in a commercial food storage facility to evaluate exposure of stored-product insects to aerosol formulations of synergized pyrethrins and the insect growth regulator methoprene. When adults of Tribolium castaneum （herbst）, the red flour beetle, and Tribolium confusum （Jacqueline DuVal）, the confused flour beetle were exposed with and without a food source to synergized pyrethrin aerosol, there was no difference in adult mortality with respect to availability of food at either 7 or 14 days after exposure （P≥0.05）. however, mortality was lower in T. confusum （40.4% and 79.3% with flour at 7 and 14 days, 38.9% and 84.8% without flour at 7 and 14 days） compared to T. castaneum （96.5% and 99.8% with flour at 7 and 14 days, 91.0% and 98.7% without flour at 7 and 14 days）. Few late-stage larvae and pupae of either species exposed to the pyrethrin aerosol emerged as adults. In tests with methoprene aerosol, adult emergence of exposed 3- and 4-week-old larvae of T. confusum was less than 2%. Only 0.3% of 4-week-old larvae of T. castaneum exposed in open and obstructed areas emerged as adults. Emergence of adults from eggs of Plodia interpunctella （hubner）, the Indianmeal moth, embedded in culture media and exposed to the methoprene aerosol was 13.2%±3.5%. Results show that the aerosols evaluated in our study could give effective control of some of the major storedproduct insect pests in commercial food storage facilities, and may offer an alternative to fumigation.

关键词： aerosols control methoprene Plodia pyrethrin Tribolium

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代数数论历史及其在ICM上的反映

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数学译林 2004年第1期23卷 1-11页

作者： h.koch 冯克勤冯绪宁 h.koch 冯克勤冯绪宁

本文以20世纪历次世界数学家大会中的大会报告为例对代数数论和算术几何的发展给出历史的综述．

关键词：代数数论算术几何虚二次域 Abel扩张同调群 L函数

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Low-complexity online correction and calibration of pedestrian dead reckoning using map matching and GPS

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Geo-Spatial Information Science 2019年第2期22卷 114-127,I0004页

作者： Fabian hölzke Johann-P.Wolff frank Golatowski Christian haubelt Institute of Applied Microelectronics and CE University of RostockRostockGermany

Dead Reckoning is a relative positioning scheme that is used to infer the change of position relative to a point of origin by measuring the traveled distance and orientation *** Dead Reckoning(PDR)applies this concept to walking *** method can be used to track someone's movement in a building after a known landmark like the building's entrance is ***,the movement of a foot and the corresponding direction change is measured and summed up,to infer the current *** and integrating the corresponding physical parameters,*** inertial sensors,introduces small errors that accumulate quickly into large distance *** of a buildings geography may reduce these errors as it can be used to keep the estimated position from moving through walls and onto likely *** this paper,we use building maps to improve localization based on a single foot-mounted inertial *** describe our localization method using zero velocity updates to accurately compute the length of individual steps and a Madgwick filter to determine the step *** though the computation of individual steps is quite accurate,small errors still accumulate in the long *** show how correction algorithms using likely and unlikely paths can rectify errors intrinsic to pedestrian dead reckoning tasks,such as orientation and displacement drift,and discuss restrictions and disadvantages of these *** also present a method of deriving the initial position and orientation from GPS *** verify our PDR correction methods analyzing the corrected and raw trajectories of six participants walking four routes of varying length and complexity through an office building,walking each route three *** quantitative results show an endpoint accuracy improvement of up to 60%when using likely paths and 23%when using unlikely ***,both approaches can also decrease accuracy in certain *** identify those scenarios and

关键词： Indoor localization Pedestrian Dead Reckoning(PDR) Inertial Navigation System(INS) map matching Zero Velocity Update(ZUPT)

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玫瑰茄的成熟度与品质Ⅳ.改良干燥与收获方式

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亚热带植物科学 1985年第2期 48-52页

作者： Khafaga E.R. h.koch 卓仁松

来自埃及、塞内加尔、印度、泰国及中美洲的五个玫瑰茄品系的成熟萼片以五种方法,即在-3℃冷冻干燥和在20℃、40℃、60℃及105℃的烘箱内干燥,以研究干燥方法对玫瑰茄两个最主要的品质特性——有机酸和花色素苷含量的影响。各种干燥方... 详细信息

来自埃及、塞内加尔、印度、泰国及中美洲的五个玫瑰茄品系的成熟萼片以五种方法,即在-3℃冷冻干燥和在20℃、40℃、60℃及105℃的烘箱内干燥,以研究干燥方法对玫瑰茄两个最主要的品质特性——有机酸和花色素苷含量的影响。各种干燥方法对所有品系均有影响。冷冻干燥法可以获得最多量的有机酸和花色素苷,但要大规模生产则太昂贵。炉烘干法与冷冻干燥相比,不论哪一种温度都破坏品质,损失最小的是40℃,此时10%的酸与20—30%的花色素苷损失;而在1O5℃时,50—75%的酸与花色素苷受破坏。商品玫瑰茄萼片质量往往较差,这是因为采收时不完全成熟或过分成熟 (枯熟)、萼片混杂了果实其它部分,外来杂质很不干净或是阳光晒干时不干净所致。为了改善这种情况,现提出一个收获方式(表2),着重注意开花期、生长期及萼片发育期间成分的变化。但是,所探讨的五个品系的这些特性都不相同,因此应按各品系所适应的特殊情况进行收获。当地的土壤、气候与经济状况均会影响收获的方式,萼片应该分散成薄层放在干净草席上晾干。这样做费用增加了些,但萼片品质比在太阳下晒干的改善了很多。

关键词：玫瑰茄萼片花色素苷商品木槿属冷冻干燥收获方式成熟度纤维性能

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Prevention of stress-related ulcer bleeding at the intensive care unit: Risks and benefits of stress ulcer prophylaxis

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World Journal of Critical Care Medicine 2016年第1期5卷 57-64页

作者： Lukas Buendgens Alexander koch frank Tacke Department of Medicine Ⅲ University Hospital Aachen

Stress-related mucosal disease is a typical complication of critically ill patients in the intensive care unit(ICU). It poses a risk of clinically relevant upper gastrointestinal(GI) bleeding. Therefore, stress ulcer prophylaxis(SUP)is recommended in high-risk patients, especially those mechanically ventilated > 48 h and those with a manifest coagulopathy. Proton pump inhibitors(PPI) and, less effectively, histamine 2 receptor antagonists(h2RA) prevent GI bleeding in critically ill patients in the ICU. however, the routine use of pharmacological SUP does not reduce overall mortality in ICU patients. Moreover, recent studies revealed that SUP in the ICU might be associated with potential harm such as an increased risk of infectious complications, especially nosocomial pneumonia and Clostridium difficile-associated diarrhea. Additionally, special populations such as patients with liver cirrhosis may even have an increased mortality rate if treated with PPI. Likewise, PPI can be toxic for both the liver and the bone marrow, and some PPI show clinically relevant interactions with important other drugs like clopidogrel. Therefore, the agent of choice, the specific balance of risks and benefits for individual patients as well as the possible dose of PPI has to be chosen carefully. Alternatives to PPI prophylaxis include h2 RA and/or sucralfate. Instead of routine SUP, further trials should investigate risk-adjusted algorithms, balancing benefits and threats of SUP medication in the ICU.

关键词： Proton pump inhibitors Clostridium difficile Intensive care unit Gastrointestinal hemorrhage Stress histamine h2 antagonists Risk assessment Pneumonia Physiological Sucralfate

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From basic properties to the Mott design of correlated delafossites

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npj Computational Materials 2021年第1期7卷 1084-1100页

作者： frank Lechermann European XFEL SchenefeldGermany Center for Computational Quantum Physics Flatiron InstituteNew YorkNYUSA

The natural-heterostructure concept realized in delafossites highlights these layered *** metallic,band-or Mott-insulating character may be associated with individual layers,inter-layer coupling still plays a decisive *** review the correlated electronic structure of PdCoO_(2),PdCrO_(2),and AgCrO_(2),showing that layer-entangled electronic states can deviate from standard classifications of interacting *** finding opens up possibilities for materials design in a subtle Mott-critical *** hidden-Mott physics,correlation-induced semimetallicity,or Dirac/flat-band dispersions in a Mott background are emerging *** with achievements in the experimental preparation,this inaugurates an exciting research field in the arena of correlated materials.

关键词： materials metallic showing

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Efficacy of an esfenvalerate plus methoprene aerosol for the control of eggs and fifth instars of Plodia interpunctella （Lepidoptera： Pyralidae）

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Insect Science 2010年第1期17卷 21-28页

作者： Emily A. Jenson frank h. Arthur James R. Nechols Kansas State University USDA-ARS Grain Marketing and Production Research Center Manhattan KS USA

Aerosol insecticides may provide an alternative to fumigants for control of the Indianmeal moth, Plodia interpunctella （hübner）, the Indianmeal moth, a major insect pest of stored processed food. In this study, eggs and larvae （5th instars） ofP. interpunctella were exposed to aerosol applications of the pyrethroid esfenvalerate and insect growth regulator methoprene, alone and in combination, in open and obstructed positions inside small sheds. When larvae were exposed to methoprene alone, adult emergence from those exposed larvae was 7.1% ± 1.5%. In contrast, adult emergence was 92.5% ± 3.5% when larvae were exposed to esfenvalerate alone. When eggs were exposed to methoprene, adult emergence of those exposed eggs was approximately 75%; however, when eggs were exposed to esfenvalerate, adult emergence was approximately 35%. In the combination treatment of methoprene plus esfenvalerate at their respective label rates, adult emergence following larval exposure was 0.91% ±0.61% compared to 16.3% ± 9.6% when eggs were exposed. Based on our results, methoprene alone is highly effective in reducing adult emergence after larval exposure. however, it is not as effective on eggs as esfenvalerate. A combination treatment of esfenvalerate plus methoprene could be used to control eggs and the wandering-phase larval stages ofP. interpunctella. An economic risk analysis also supports a strategy of combining methoprene and esfenvalerate.

关键词： control Indianmeal moth Plodia interpunctella

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