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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

Dissecting symbiosis cell by cell

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Molecular Plant 2023年第2期16卷 308-309页

作者： Manuel frank Dugald Reid Department of Molecular Biology and Genetics Aarhus UniversityUniversitetsbyen 818000Aarhus CDenmark Department of Animal Plant and Soil SciencesSchool of AgricultureBiomedicine and EnvironmentLa Trobe UniversityMelbourneVIC 3086Australia

Symbiotic nitrogen fixation in legumes occurs in specialized root organs called *** development requires coordination across tissues as infection progresses from the epidermis to growing nodules derived from the cortex or ***,functional nodules include a variety of specialized cells,including those that house the nitrogen-fixing *** combination of developmental changes across tissues and specialized functions acquired by nodule cells makes dissecting the process difficult using bulk analysis of gene expression,proteins,and metabolites.

关键词： organs cortex specialized

Influence of groundwater depth on species composition and community structure in the transition zone of Cele oasis

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journal of Arid Land 2010年第4期2卷 235-242页

作者： frank M. THOMAS Department of Geobotany University of Trier Behringstraβe 21 54296 Trier Germany

The paper analyzes the hypothesis that the distribution of dominant plant species and characteristics of plant communities are related to groundwater depth. The results showed that variations of groundwater depth impacted distributions and characteristics of dominant plant communities. However, besides groundwater depth, the community composition and species diversity were also influenced by physiognomy of the habitat. Based on the similarity coefficient, the differences between dominant plant communities were significant at different groundwater depths. Compared with other results relating to desert vegetation and groundwater depth, variations of community distribution were similar at the large spatial scale. However, in this extremely arid region, there were significant differences in community type and community succession when compared with other arid regions, especially in relationship to deep groundwater depth. With groundwater depth from deep to shallow, communities transformed with the sequence of Alhagi communities, Tamarix spp. communities, Populus communities, Phragmites communities, and Sophora communities. At groundwater depth of less than 6.0 m, the community type and composition changed, and the species diversity increased. Among these dominant species, Tamarix exhibited the biggest efficiency in resource utilization according to niche breadth, which means it possessed the best adaptability to environmental conditions at the oasis margins.

关键词： groundwater depth community characteristic niche breadth oases Taklamakan desert

Improving TRAIL-induced apoptosis in cancers by interfering with histone modifications

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Cancer Drug Resistance 2020年第4期3卷 791-803页

作者： Bao-jie Zhang Deng Chen frank j.Dekker Wim j.Quax University of Groningen Department of Chemical and Pharmaceutical BiologyGroningen Research Institute of PharmacyUniversity of GroningenGroningen 9713 AVThe Netherlands

Epigenetic regulation refers to alterations to the chromatin template that collectively establish differential patterns of gene ***-translational modifications of the histones play a key role in epigenetic regulation of gene *** this review,we provide an overview of recent studies on the role of histone modifications in *** tumour-selective ligands such as tumor necrosis factor-related apoptosis-inducing ligand(TRAIL)are well-considered as promising anti-tumour therapies,we summarise strategies for improving TRAIL sensitivity by inhibiting aberrant histone modifications in *** this perspective we also discuss new epigenetic drug targets for enhancing TRAIL-mediated apoptosis.

关键词： Epigenetics histone modification tumor necrosis factor-related apoptosis-inducing ligand selective epigenetic inhibitors apoptosis

Sprinkler rotation and water application rate for the newly-designed complete fluidic sprinkler and impact sprinkler

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International journal of Agricultural and Biological Engineering 2014年第4期7卷 38-46页

作者： frank ADwomoh Yuan Shouqi Li Hong Research Center of Fluid Machinery Engineering and Technology Jiangsu UniversityZhenjiang Jiangsu Province212013China School of Engineering Koforidua PolytechnicP.O.Box KF 981KoforiduaEastern RegionGhana

One important indicator of the good performance of rotating sprinklers is the uniformity of *** objective of this experimental study was to investigate the rotation uniformity and water application rate of the newly designed complete fluidic sprinkler in comparison to the widely used impact sprinkler,with the goal to offer recommendations to improve the fluidic sprinkler’s operation ***-sprinkler water application experiments were conducted in accordance with the American Society of Agricultural and Biological Engineers *** completion time through the four quadrants of rotation and water delivery in catch cans were measured at different operating pressures for each sprinkler-nozzle size *** capabilities of Matrix Laboratory were employed to simulate the overlap of adjacent quadrants and to visualize the effect of sprinkler rotation speed variation on water application *** completion time variations were small for both impact and fluidic ***,variations in completion time through the quadrants were higher for the fluidic sprinkler compared to the impact *** higher variations in water application rates were also observed for the fluidic *** optimization of the design features of the fluidic component is necessary to improve rotation stability and to minimize variability in water application rate of the fluidic *** study significantly highlighted some performance qualities of the complete fluidic sprinkler in comparison to that of the impact *** findings of this research will help to improve the efficiency of the new type complete fluidic sprinkler.

关键词： sprinkler rotation variation water application rate complete fluidic sprinkler impact sprinkler rotation uniformity

PHASE STRUCTURES AND TRANSITION BEHAVIORS OF A TRIPHENYLENE DISCOTIC LIQUID CRYSTAL

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Chinese journal of Polymer Science 2007年第1期25卷 57-71页

作者： Kwang-Un jeong Alexander j.jing Bart Mansdorf Matthew j.Graham frank W.Harris 程正迪 Maurice Morton Institute and Department of Polymer Science The University of AkronAkronOhio 44325-3909USA

The phase behaviors and structures of a triphenylene-derived discotic liquid crystal （LC） hexa-n-octoxyl- triphenylene （C8HET） were studied using the combined techniques of differential scanning calorimetry （DSC）, wide angle X-ray diffraction （WAXD）, selected area electron diffraction （SAED） and polarized light microscopy （PLM）. Onedimensional （1D） powder WAXD results at different temperatures coupled with DSC and PLM observations revealed that the C8HET compound possessed an LC phase and three different crystalline （K3, K2 and K1） phases below the isotropic （I） melt. The I←→ LC phase transition was thermodynamically reversible and independent of the heating and cooling rates. The development and experimental observation of the three crystalline phases relied on different thermal histories. Among the three crystalline phases in CSHET, the K3 phase is the most stable phase, while the K2 and K1 phases are metastable. Note that the K1 phase only formed via a quenching process. Oh the basis of structure sensitive diffraction experiments such as 2D WAXD of oriented samples and SAED of single crystals, detailed structures and molecular packings of these four ordered phases were identified. The LC phase exhibited a hexagonal columnar phase with 2D lattice dimensions ofa = b = 2.38 nm and γ= 120°. All the three crystalline phases possess monoclinic unit cells, yet the y angle is not 90° in the cases of the K2 and the K3 phases, while in the case of the K1 phase the a angle is not 90°.

关键词： Triphenylene discotic liquid crystal Metastability Crystal structure Columnar phase Phase transitions.

Measurement and Interpretation of Connectivity of Chinese Cities in World City Network,2010

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Chinese Geographical Science 2013年第3期23卷 261-273页

作者： Ben DERUDDER Peter j TAYLOR Michael HOYLER NI Pengfei LIU Xingjian ZHAO Miaoxi SHEN Wei frank WITLOX Department of Geography Ghent University School of the Built and Natural Environment Northumbria University Department of Geography Loughborough University Chinese Academy of Social Sciences Department of Geography University of Cambridge South China University of Technology ESSCA School of Management

This is an empirical paper that measures and interprets the position of Chinese cities in the world city network in 2010. Building on a specification of the world city network as a′interlocking network′in which business services firms play the crucial role in city network formation, information is gathered about the presence of global service firms in cities. This information is converted into data to provide the′service value′of a city for a firm′s provision of corporate services in a 526(cities)×175(firms) matrix. These data are then used as the input to the interlocking network model in order to measure cities′connectivity and its predominant geographical orientation. Here we focus on the position of some key Chinese cities in this regard, and discuss and interpret results in the context of the urban dimensions of the′opening up′of the Chinese economy.

关键词： world city network advanced producer services Shanghai Hong Kong Beijing

Investigating unsafe behaviours in traffic conflict situations:An observational study in Nigeria

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journal of Traffic and Transportation Engineering(English Edition) 2019年第5期6卷 482-492页

作者： Chinebuli Uzondu Samantha jamson frank Lai Institute for Transport Studies University of Leeds Leeds LS2 9JT UK Department of Transport Management Technology Federal University of Technology Owerri Owerri Nigeria

Although road users are aware of the possible risks of engaging in unsafe behaviours while driving,they continue to do *** behaviours often contribute to traffic incidents and crashes involving them and other road *** study set out to analyse the effect of road user type,location and time of day on unsafe driving behaviours observed in traffic conflict *** were collected by road side observation at three different locations in the eastern part of Nigeria using the traffic conflict technique(TCT).This approach was adopted to overcome the inherent problems associated with reliable,inadequate and accessible crash data in *** total 946 traffic conflicts were observed and statistical testing showed that drivers were involved in one or more unsafe behaviours prior to these *** all unsafe behaviours observed,the incorrect use of indicators(13.3%) and tailgating(11.3%) were found to be the most prevalent,while road user type,location and time of day were found to be statistically associated with passenger scouting and other unsafe *** drivers were significantly more likely to engage in unsafe behaviours than vehicle *** are also more likely to engage in unsafe behaviours on straight ***,a greater number of these unsafe behaviours were observed during the peak *** is recommended that better road infrastructure,more effective regulations and enforcement,and proper road safety education could help improve traffic safety in Nigeria.

关键词： Unsafe behaviour Traffic conflict Traffic safety Crash data

Predictors of first-pass success intubations in the emergency departments in Germany:analysis of the German Airway Registry between 2015 and 2022

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World journal of Emergency Medicine 2024年第6期15卷 490-493页

作者： Christian Hohenstein Lucas Rudnik frank Bloos Department of Emergency Medicine Zentralklinik Bad BerkaAffiliation University of MarburgFaculty of MedicineBad Berka 99437Germany University of jena Faculty of MedicineJena 07747Germany Department of Anaesthesiology and Intensive Care Medicine University Hospital JenaJena 07747Germany

In the field of airway management,there is no national registry in Germany that captures data on emergency airway *** improve quality,one needs to know the data *** include gender,age,indications for emergency airway management,level of education,the intubating department,the intubation method,and other factors that can serve as a basis for quality improvement changes.

关键词： intubation airway education