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Genetic diversity and differentiation follow secondary succession in a multi-species study on woody plants from subtropical China

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Journal of Plant Ecology 2017年第1期10卷 213-221页

作者： Christoph Z.Hahn Stefan G.Michalski Markus fischer Walter Durka Department of Community Ecology(BZF) Helmholtz Centre for Environmental Research—UFZTheodor-Lieser-Straße 4D-06120 HalleGermany Institute of Plant Sciences University of BernAltenbergrain 21CH-3013 BernSwitzerland German Centre for Integrative Biodiversity Research(iDiv)Halle-Jena-Leipzig Deutscher Pl.5E04103 LeipzigGermany

Aims Species diversity and genetic diversity may be affected in parallel by similar environmental ***,genetic diversity may also be affected independently by habitat *** aim at disentangling relationships between genetic diversity,species diversity and habitat characteristics of woody species in subtropical *** We studied 11 dominant tree and shrub species in 27 plots in Gutianshan,China,and assessed their genetic diversity(A_(r))and population differentiation(F′_(ST))with microsatellite *** tested if Ar and population specific F′_(ST) were correlated to local species diversity and plot ***-model inference and model averaging were used to determine the relative importance of each ***,we tested for isolation-by-distance(IBD)and isolation-by-elevation by regressing pairwise F′_(ST) against pairwise spatial and elevational *** Findings Genetic diversity was not related to species diversity for any of the study ***,our results do not support joint effects of habitat characteristics on these two levels of ***,genetic diversity in two understory shrubs,Rhododendron simsii and Vaccinium carlesii,was affected by plot age with decreasing genetic diversity in successionally older *** differentiation increased with plot age in *** and Lithocarpus *** shows that succession can reduce genetic diversity within,and increase genetic diversity between ***,we found four cases of IBD and two cases of *** former indicates inefficient pollen and seed dispersal by animals whereas the latter might be due to phenological *** patterns indicate that succession can affect genetic diversity without parallel effects on species diversity and that gene flow in a continuous subtropical forest can be restricted even at a local scale.

关键词： Allelic richness population differentiation habitat characteristics gene flow species-genetic diversity correlation SGDC

Socioecological drivers facilitating biodiversity conservation in traditional farming landscapes

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Ecosystem Health and Sustainability 2015年第9期1卷 8-17页

作者： Ine Dorresteijn Jacqueline Loos Jan Hanspach Joern fischer Faculty of Sustainability Leuphana University LuneburgScharnhorststraße 121335 LuneburgGermany

Traditional farming landscapes have evolved as tightly coupled socioecological systems that support high ***,land-use change severely threatens the high biodiversity of these *** nature conservation in such landscapes requires a thorough understanding of the key drivers underpinning *** empirical research on mammals,birds,butterflies,and plants in a traditional cultural landscape in Romania,we revealed seven hypothesized drivers facilitating biodiversity *** proportions of three main land-use types support the landscape species pool,most likely through habitat connectivity and frequent spillover between land-use *** complementation and supplementation provide additional habitat for species outside their core *** of woody vegetation cover and gradients in land-cover heterogeneity provide mosaic landscapes with wide ranges of *** land-use practices underpin landscape heterogeneity,traditional land-use elements such as wood pastures,and human-carnivore ***-down predator control may limit herbivore ***,cultural ties between humans and nature have a central influence on people’s values and sustainable use of natural *** approaches should aim to maintain or restore these socioecological drivers by targeting the heterogeneous character of the forest-farmland mosaic at large scales through"broad and shallow"conservation *** large-scale measures should be complemented with"deep and narrow"conservation measures addressing specific land-use types,threats,or *** both cases,conservation measures should integrate the entire socioecological system,by recognizing and strengthening important links between people and the environment.

关键词： countryside biogeography coupled human and natural systems cultural landscapes human–environment systems landscape ecology resilience Romania Special Feature:Ecosystem Management in Transition in Central and Eastern Europe Transylvania

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微尺度声操控研究及其生物学应用

Engineering 2023年第5期24卷 13-16,I0001页

作者： Zhichao Ma Peer fischer Max Planck Institute for Intelligent Systems Stuttgart 70569Germany Institute of Physical Chemistry University of StuttgartStuttgart 70569Germany School of Biomedical Engineering Shanghai Jiao Tong UniversityShanghai 200030China

Acoustic waves-and ultrasound waves in particular-are biocompatible,with excellent transmission through biological ***,the wavelength and intensity of acoustic waves can be tuned over several orders of *** notably,the commonly used 10–300 MHz frequency range is attractive for biomedical applications,as its wavelength in water(5–150μm)corresponds to the cellular-length scale.

关键词：声操控生物学应用微尺度

Experimental and Numerical Analysis of Natural Bio and Syngas Swirl Flames in a Model Gas Turbine Combustor

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Journal of Thermal Science 2016年第5期25卷 460-469页

作者： S.Iqbal A.C.Benim S.fischer F.Joos D.KluB A.Wiedermann CFS Dept.Mechanical and Process Eng.Düsseldorf University of Applied Sciences Laboratory of Turbomachinery Helmut Schmidt University Viessmann Werke Berlin GmbH Engineering Gas Turbines MAN Diesel and Turbo SE

Turbulent reacting flows in a generic swirl gas turbine combustor model are investigated both numerically and *** the investigation,an emphasis is placed upon the external flue gas recirculation,which is a promising technology for increasing the efficiency of the carbon capture and storage process,which,however,can change the combustion behaviour significantly.A further emphasis is placed upon the investigation of alternative fuels such as biogas and syngas in comparison to the conventional natural *** are also investigated numerically using the open source CFD software *** the numerical simulations,a laminar flamelet model based on mixture fraction and reaction progress variable is *** turbulence model,the SST model is used within a URANS *** results are compared with the experimental data,where a fair agreement is observed.

关键词： Gas turbine combustion turbulent combustion URANS laminar flamelet method

Nutritional stress reduces flight performance and exploratory behavior in a butterfly

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Insect Science 2019年第5期26卷 897-910页

作者： Elisabeth Reim Danny Eichhorn Jan D.Roy Philip O.M.Steinhoff Klaus fischer Zoological Institute and Museum Greifswald UniversityGreifswaldGermany

Anthropogenic global change, including agricultural intensification and climate change, poses a substantial challenge to many herbivores due to a reduced availability of feeding resources. The concomitant food stress is expected to detrimentally affect performance, amongst others in dispersal-related traits. Thus, while dispersal is of utmost importance to escape from deteriorating habitat conditions, such conditions may negatively feedback on the ability to do so. Therefore, we here investigate the impact of larval and adult food stress on traits related to dispersal ability, including morphology, physiology, flight performance, and exploratory behavior, in a butterfly. We show that inadequate nutrition during development and in the adult stage dim inishes flight performance, despite som e reallocation of somatic resources. Detrimental effects of food stress on flight performance were mainly caused by reductions in body mass and storage reserves. Similar results were found for exploratory behavior. Furthermore, exploratory behavior was found to be (moderately) repeatable at the individual level, which might indicate the existence of a personality trait. This notion is further supported by the fact that flight performance and exploratory behavior were positively correlated, potentially suggesting the existence of a dispersal syndrome. In summary, our findings may have important implications for dispersal in natural environments, as the conditions requiring dispersal the m ost impair flight ability and thereby likely dispersal rates.

关键词： condition dispersal syndrome flight ability food stress habitat degradation resource allocation

First-line endoscopic treatment with over-the-scope clips significantly improves the primary failure and rebleeding rates in high-risk gastrointestinal bleeding: A single-center experience with 100 cases

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World Journal of Gastroenterology 2016年第41期22卷 9162-9171页

作者： Hans-Jürgen Richter-Schrag Torben Glatz Christine Walker Andreas fischer Robert Thimme Center of Interdisciplinary Gastrointestinal Endoscopy Department of Medicine II Medical Center-University of Freiburg Faculty of Medicine University of Freiburg Department of General and Visceral Surgery Medical Center-University of Freiburg Faculty of Medicine University of Freiburg

AIM To evaluate rebleeding, primary failure(PF) and mortality of patients in whom over-the-scope clips(OTSCs) were used as first-line and second-line endoscopic treatment(FLET, SLET) of upper and lower gastrointestinal bleeding(UGIB, LGIB).METHODS A retrospective analysis of a prospectively collected database identified all patients with UGIB and LGIB in a tertiary endoscopic referral center of the University of Freiburg, Germany, from 04-2012 to 05-2016(n= 93) who underwent FLET and SLET with OTSCs. The complete Rockall risk scores were calculated from patients with UGIB. The scores were categorized as < or ≥ 7 and were compared with the original Rockall data. Differences between FLET and SLET were calculated. Univariate and multivariate analysis were performed to evaluate the factors that influenced rebleeding after OTSC *** Primary hemostasis and clinical success of bleeding lesions(without rebleeding) was achieved in 88/100(88%) and 78/100(78%), respectively. PF was significantly lower when OTSCs were applied as FLET compared to SLET(4.9% vs 23%, P = 0.008). In multivariate analysis, patients who had OTSC placement as SLET had a significantly higher rebleeding risk compared to those who had FLET(OR 5.3; P = 0.008). Patients with Rockall risk scores ≥ 7 had a significantly higher in-hospital mortality compared to those with scores < 7(35% vs 10%, P = 0.034). No significant differences were observed in patients with scores < or ≥ 7 in rebleeding and rebleeding-associated *** Our data show for the first time that FLET with OTSC might be the best predictor to successfully prevent rebleeding of gastrointestinal bleeding compared to SLET. The type of treatment determines the success of primary hemostasis or primary failure.

关键词： Gastrointestinal bleeding Rockall risk score Over-the-scope clip First-line endoscopic treatment Second-line endoscopic treatment

Particles dispersion on fluid-liquid interfaces

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Particuology 2011年第1期9卷 1-13页

作者： Sathish Gurupatham Bhavin Dalal Md.Shahadat Hossain Ian S.fischer Pushpendra Singh Daniel D.Joseph Department of Mechanical Engineering New Jersey Institute of Technology Department of Aerospace Engineering and Mechanics University of Minnesota Department of Mechanical and Aerospace Engineering University of California Irvine

This paper is concerned with the dispersion of particles on the fluid-liquid interface. In a previous study we have shown that when small particles, e.g., flour, pollen, glass beads, etc., contact an air-liquid interface, they disperse rapidly as if they were in an explosion. The rapid dispersion is due to the fact that the capillary force pulls particles into the interface causing them to accelerate to a large velocity. In this paper we show that motion of particles normal to the interface is inertia dominated; they oscillate vertically about their equilibrium position before coming to rest under viscous drag. This vertical motion of a particle causes a radially-outward lateral （secondary） flow on the interface that causes nearby particles to move away. The dispersion on a liquid-liquid interface, which is the primary focus of this study, was relatively weaker than on an air-liquid interface, and occurred over a longer period of time. When falling through an upper liquid the particles have a slower velocity than when falling through air because the liquid has a greater viscosity. Another difference for the liquid-liquid interface is that the separation of particles begins in the upper liquid before the particles reach the interface. The rate of dispersion depended on the size of the particles, the densities of the particle and liquids, the viscosities of the liquids involved, and the contact angle. For small particles, partial pinning and hysteresis of the three-phase contact line on the surface of the particle during adsorption on liquid-liquid interfaces was also important. The frequency of oscillation of particles about their floating equilibrium increased with decreasing particle size on both air-water and liquid-liquid interfaces, and the time to reach equilibrium decreased with decreasing particle size. These results are in agreement with our analysis.

关键词： Adsorption Interfacial tension Particle dispersion Fluid–liquid interface Capillary force Viscous drag

Trends in Monthly Temperature and Precipitation Extremes in the Zhujiang River Basin,South China(1961-2007)

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Advances in Climate Change Research 2010年第2期1卷 63-70页

作者： Thomas fischer Marco Gemmer Lliu Liu Buda Su National Climate Center China Meteorological Administration

Monthly temperature and precipitation time-series for the Zhujiang River Basin are analyzed in order to identify changes in climate extremes. Daily temperature and precipitation data from 1961 to 2007 of 192 meteorological stations are used. Two temperature indicators （monthly mean and monthly maximum mean） and three precipitation indicators （monthly total, monthly maximum consecutive 5-day precipitation, and monthly dry days） are analyzed. Tendencies in all five indicators can be observed. Many stations show significant positive trends （above the 90% confidence level） for monthly mean temperatures and monthly maximum mean temperatures. For all months, a significant increase in temperature from 1961 to 2007 can be observed in the entire basin with the coastal area in particular. Positive trends of precipitation extremes can be observed from January to March. Negative trends are detected from September to November. The number of dry days in October increased significantly at 40% of all meteorological stations. Stations with changes of monthly precipitation extremes are scattered over the Zhujiang River Basin. An aggregation of heat waves and droughts can be detected which is accompanied by significant increases of temperature extremes and the negative tendencies in precipitation extremes. The detection of tendencies in climate station density. extremes essentially relies on a good data quality and high

关键词： temperature precipitation extremes Zhujiang River Basin China

Do aphids actively search for ant partners？

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Insect Science 2015年第2期22卷 283-288页

作者： Christophe Y. fischer Maryse Vanderplanck Georges C. Lognay Claire Detrain Francois J. Verheggen Laboratory of Analytical Chemistry University of Liege Gembloux Agro-Bio Tech Gembloux Research Institute of Biosciences Laboratory of Zoology University of Mons Mons Unit of Social Ecology Universit6 Libre de Bruxelles Brussels Department of Functional and Evolutionary Entomology University of Liege Gembloux Agro-Bio Tech Gembloux Belgium

The aphid-ant mutnalistic relationships are not necessarily obligate for neither partners but evidence is that such interactions provide them strong advantages in terms of global fitness. While it is largely assumed that ants actively search for their mutualistic partners namely using volatile cues; whether winged aphids （i.e., aphids＇ most mobile form） are able to select ant-frequented areas had not been investigated so far. Ant-frequented sites would indeed offer several advantages for these aphids including a lower predation pressure through ant presence and enhanced chances of establishing mutuaslistic interactions with neighbor ant colonies. In the field, aphid colonies are often observed in higher densities around ant nests, which is probably linked to a better survival ensured by ants＇ services. Nevertheless, this could also result from a preferential establishment of winged aphids in ant-frequented areas. We tested this last hypothesis through different ethological assays and show that the facultative myrmecophilous black bean aphid, Aphisfabae L., does not orientate its search for a host plant preferentially toward ant-frequented plants. However, our results suggest that ants reduce the number of winged aphids leaving the newly colonized plant. Thus, ants involved in facultative myrmecophilous interactions with aphids appear to contribute to structure aphid populations in the field by ensuring a better establishment and survival of newly established colonies rather than by inducing a deliberate plant selection by aphid partners based on the proximity of ant colonies.

关键词： ant aphid Aphisfabae Lasius niger mutualism partner research