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Tree diversity and nectar composition affect arthropod visitors on extrafloral nectaries in a diversity experiment

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Journal of Plant Ecology 2017年第1期10卷 201-212页

作者： Michael Staab Joel Methorst Jan Peters Nico Blüthgen Alexandra-Maria Klein Faculty of Environment and Natural Resources Chair of Nature Conservation and Landscape EcologyUniversity of FreiburgTennenbacher Straße 479106 FreiburgGermany Institute of Ecology Leuphana University of LüneburgScharnhorststraße 121335 LüneburgGermany Ecological Network Group Department of BiologyTechnical University DarmstadtSchnittspahnstraße 1064287 DarmstadtGermany

Aims Plants with extrafloral nectaries(EFNs)are common in tropical and subtropical habitats and,despite many other arthropods also forage for EFN,most studies solely focused on the defense mutualisms between EFN plants and *** study aims at a quantitative assessment of the entire arthropod community that visits EFN trees to compare visitor communities between different tree species to disentangle the mechanisms that may drive EFN visitor community *** also test for tree diversity effects on EFN visitors,as it is unknown if local tree species richness relates to the abundance and species richness of arthropods foraging for *** We sampled EFN-visiting arthropods in the experimental tree species richness gradient of the BEF-China Experiment,the currently largest forest diversity experiment in the world,and tested if tree species richness affects EFN visitors and if visitor community composition differs between EFN tree *** a second step,we analyzed the EFN of Ailanthus altissima and Triadica cochinchinensis,the two EFN tree species with highest visitor abundance,for sugars and amino acids(AA)to test if tree species-specific differences in nectar chemistry translate to differing visitor ***,we conducted a choice experiment using different artificial nectar solutions to test if nectar quality affects foraging decisions of ants,the most frequent EFN visitors in our study *** Findings EFN trees in young successional forests in subtropical South-East China are visited by a diverse assemblage of arthropods including ants,beetles,flies,and *** ants accounted for about 75%of all individuals,non-ant visitors were by far more species *** abundance and species richness declined with increasing tree species richness,suggesting a resource dilution effect,because plots with more tree species had proportionally less EFN tree individuals and thus lower nectar *** altissima and ***

关键词： amino acids BEF-China choice experiment formicidae HPLC chemical analysis

Selectivity in feeding preferences and ranging patterns in spider monkeys Ateles geoffroyi yucatanensis of northeastern Yucatan peninsula, Mexico

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Current Zoology 2013年第1期59卷 125-134页

作者： Carmen SCHERBAUM Alejandro ESTRADA Department of Animal Ecology and Tropical Biology Biozentrum University of Wiirzburg Germany Estacion de Biologia Tropical Los Tuxtlas Instituto de Biologfa Universidad Nacional Aut6noma de M6xico Apartado Postal94 San Andres Tuxtla Veracruz M6xico C. P. 95700

The spider monkey, a fruit specialist and important seed dispersal agent in the Neotropics, is an endangered primate due to habitat loss, hunting and the pet trade. Spider monkeys have been the subject of a few studies in Central and South Ame- rica, but little is known about the diet and ranging for this primate in southern Mexico. Here we report the results of a six-month long study （October 2010 to March 2011） of the feeding preferences and ranging patterns of the Yucatan spider monkey Ateles geoffroyi yucatanensis living in the ＂Ya＇ax＇che＂ reserve by the Caribbean coast in northeast Yucatan peninsula. Focal animal and scan sampling as well as GPS tracking were used to document spider monkey feeding behavior, location of food trees and ranging in the reserve. The spider monkeys used 36 species of plants （94% trees; n = 432） and six non tree morphospecies as a source of food. Six tree species accounted for 〉~80% of total feeding time and for 74% of all trees used. Fruits accounted for 59% of total feeding time, followed by leaves （35%）, palm piths （5%） and other plant parts （1%）. Total range used by the monkeys was esti- mated at 43% of semievergreen rainforest habitat available （ca 40ha）. Range use was not random with segments showing light, moderate and heavy use; the use of different areas of their range varied monthly and was closely linked to the spatial dispersion of the trees used for food [Current Zoology 59 （1）： 125-134, 2013].

关键词： Primates Frugivory Neotropics Conservation Seed dispersal

Exotic tree seedlings are much more competitive than natives but show underyielding when growing together

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Journal of Plant Ecology 2013年第4期6卷 305-315页

作者： Heike Kawaletz Inga Mölder Stefan Zerbe Peter Annighöfer André Terwei Christian Ammer Department of Silviculture and Forest Ecology of the Temperate Zones University of GöttingenBüsgenweg 137077 GöttingenGermany Energieagentur Region Göttingen e.V. Berliner Str.237073 GöttingenGermany Faculty of Science and Technology Free University of Bozen-BolzanoPiazza Università539100 BolzanoItaly

Aims Invasive species continue to be a worldwide threat to ecosystems mainly as a cause for biodiversity *** ecosystems,for example,are subject to a change in species composition due to the invasion of exotic *** the attributes that cause the strong competitiveness of several exotic species may improve the ability to understand and effectively manage plant invasions in the *** this study the following hypotheses were tested:(1)biomass production of below-and aboveground plant compo-nents of the exotic tree species is higher than that of the natives,resulting in a higher competitiveness of the exotics;(2)the exclu-sion of root competition has a positive effect on the biomass pro-duction of the inferior native species;and(3)mixtures of native and exotic species yield a higher biomass production than the respective *** a pot experiment,containing about 2000 tree seedlings,was *** investigated the biomass productivity and growth reactions of two native(Quercus robur l.,Carpinus betulus l.)and two exotic tree species(Prunus serotina Ehrh.,Robinia pseudoacacia l.)in different intra-and interspecific,competitive situations with and without the influence of root *** Findingsthe biomass production of both exotic species was significantly higher and led to a strong competitive advantage,resulting in a biomass decrease of the less competitive native *** high belowground biomass of both exotic species had a negative effect on the biomass *** competitive pressure of exotic tree seedlings on the native ones was largely driven by root ***,mixtures of native and exotic tree species had a higher productivity than their growth in monocultures would have *** was lower for exotic species in mixtures with the less productive native species compared to the competition in monocultures or in mixture with the other highly productive exotic ***,b

关键词： competition biomass production pot experiment invasive species Prunus serotina Robinia pseudoacacia

Antidepressant fluoxetine and its potential against colon tumors

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World Journal of Gastrointestinal Oncology 2014年第1期6卷 11-21页

作者： Helga Stopper Sergio Britto Garcia Ana Maria Waaga-Gasser Vinicius Kannen Department of Toxicology University of Wuerzburg Department of Pathology Medical School of Ribeiro PretoUniversity of So PauloRibeiro Preto Department of Surgery I Molecular Oncology and ImmunologyUniversity of Wuerzburg

Colon cancer is one of the most common tumors worldwide,with increasing incidence in developing *** treated with fluoxetine(FLX) have a reduced incidence of colon cancer,although there still remains great controversy about the nature of its *** we explore the latest achievements related to FLX treatment and colon ***,we discuss new ideas about the mechanisms of the effects of FLX treatment in colon *** leads to the hypothesis of FLX arresting colon tumor cells at the at G1 cell-cycle phase through a control of the tumor-related energy generation *** believe that the potential of FLX to act against tumor metabolism warrants further investigation.

关键词： Fluoxetine Colon cancer Cancer therapy Tumor metabolism

Productivity constraints on Citron-crested Cockatoos in a rich community of large hole-nesting birds

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Avian Research 2022年第1期13卷 25-35页

作者： Anna Reuleaux Benny A.Siregar Nigel J.Collar Ani Mardiastuti Stuart J.Marsden Department of Natural Sciences Manchester Metropolitan UniversityManchesterUK Burung Indonesia BogorIndonesia BirdLife International CambridgeUK Bogor Agricultural University(IPB University) BogorIndonesia

Knowledge of breeding success and its limiting factors is crucial in assessing species’conservation *** cavity-nesters,parrots are particularly influenced by the availability of suitable cavities and low breeding output,whether due to natural processes or *** the island of Sumba,Indonesia,the Critically Endangered Citron-crested Cockatoo(Cacatua citrinocristata)has the added problem of co-existing with an unusually rich hole-nesting bird community in a forested environment much constrained by habitat *** monitored 95 nesting cavities of cockatoos and their competitors and potential nest-predators,over one to four breeding seasons,using a combination of camera-traps,direct checks on nest contents,and observations from the *** for suitable cavities was intense among three large parrot species,two owls and a *** rates by potential competitors were higher at unoccupied cavities than at those containing active nests,reflecting the guarding behaviour of the *** Endangered Sumba Hornbill(Rhyticeros everetti)dominated observed direct confrontations and was the most frequent visitor to active parrot nests,suggesting a further role as a potential *** prospected many cavities but rarely then attempted to nest:instead the sites were usually occupied by other cavity-nesters,or by *** the few cavities where cockatoos did breed,predation pressure was likely low,and observed success rate high(10 successful of 15 nests),although the low number of nests found early in the breeding cycle suggests that some may have failed before *** competition for cavities suggests a shortage of suitable nest-sites,the need for preservation of old hole-bearing trees and a role for ***,known,safe artificial nest-sites would also provide opportunities to assess the scale of nest-site shortage,allow camera placements to study productivity,exclude some competitors and predators,and prevent ill

关键词： Camera-traps Competition Conservation Hornbills Parrots Predation

Nitrosative stress in human spermatozoa causes cell death characterized by induction of mitochondrial permeability transition-driven necrosis

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Asian Journal of Andrology 2018年第6期20卷 600-607页

作者： Pamela Uribe Maria E Cabrillana Miguel W Forn Favi/m Treulen Rodrigo Boguen Vladimir Isachenko Evgenia Isachenko Ratil S inchez Juana V Villegas Center of Reproductive Biotechnology-Scientific and Technological Bioresource Nucleus（CEBIOR-BIOREN） University of La FronteraTemuco 4811230Chile Center of Excellence in Translational Medicine University of La FronteraTemuco 4810296Chile Department of Internal Medicine Faculty of MedicineUniversity of La FronteraTemuco 4781218Chile %aboratory of Andrology Research of Mendoza（LIAM）Institute of Histology and Embriology of Mendoza（IHEM）Histology and Embryology Area Department of Morphology and PhysiologySchool of MedicineNational University of Cuyo and CCT-MendozaCONICETMendoza 5500Argentin SResearch Institute（CIUDA） Medicine FacultyAcencagua UniversityMendoza 5500Argentina Research Group for Reproductive Medicine Cologne UniversityCologne 50937Germany Department of Preclinical Sciences Faculty of MedicineUniversity of La FrenteraTemuco 4781218Chile.

Peroxynitrite is a highly reactive nitrogen species and a potent inducer of apoptosis and necrosis in somatic cells. Peroxynitrite-induced nitrosative stress has emerged as a major cause of impaired sperm function; however, its ability to trigger cell death has not been described in human spermatozoa. The objective here was to characterize biochemical and morphological features of cell death induced by peroxynitrite-mediated nitrosative stress in human spermatozoa. For this, spermatozoa were incubated with and without （untreated control） 3-morpholinosydnonimine （SIN-l）, in order to generate peroxynitrite. Sperm viability, mitochondrial permeability transition （MPT）, externalization of phosphatidylserine, DNA oxidation and fragmentation, caspase activation, tyrosine nitration, and sperm ultrastructure were analyzed. The results showed that at 24 h of incubation with SIN-l, the sperm viability was significantly reduced compared to untreated control （P〈 0.001）. Furthermore, the MPT was induced （P〈 0.01） and increment in DNA oxidation （P 〈 0.01）, DNA fragmentation （P 〈 0.01）, tyrosine nitration （P 〈 0.0001） and ultrastructural damage were observed when compared to untreated control. Caspase activation was not evidenced, and although phosphatidylserine externalization increased compared to untreated control （P 〈 0.001）, this process was observed in 〈10% of the cells and the gradual loss of viability was not characterized by an important increase in this parameter. In conclusion, peroxynitrite-mediated nitrosative stress induces the regulated variant of cell death known as MPT-driven necrosis in human spermatozoa. This study provides a new insight into the pathophysiology of nitrosative stress in human spermatozoa and opens up a new focus for developing specific therapeutic strategies to better preserve sperm viability or to avoid cell death.

关键词： necrosis nitrosative stress oxidative stress peroxynitrite sperm cell death

Integrating water use systems and soil and water conservation measures into a hydrological model of an Iranian Wadi system

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Journal of Arid Land 2020年第4期12卷 545-560页

作者： Nariman MAHMOODI Jens KIESEL Paul D WAGNER Nicola FOHRER Department of Hydrology and Water Resources Management Institute for Natural Resource ConservationKiel UniversityKiel 24118Germany Department of Ecosystem Research Leibniz-Institute of Freshwater Ecology and Inland Fisheries(IGB)Berlin 12489Germany

Water resources are precious in arid and semi-arid areas such as the Wadis of Iran. To sustainably manage these limited water resources, the residents of the Iranian Wadis have been traditionally using several water use systems(WUSs) which affect natural hydrological processes. In this study, WUSs and soil and water conservation measures(SWCMs) were integrated in a hydrological model of the Halilrood Basin in Iran. The Soil and Water Assessment Tool(SWAT) model was used to simulate the hydrological processes between 1993 and 2009 at daily time scale. To assess the importance of WUSs and SWCMs, we compared a model setup without WUSs and SWCMs(Default model) with a model setup with WUSs and SWCMs(WUS-SWCM model). When compared to the observed daily stream flow, the number of acceptable calibration runs as defined by the performance thresholds(Nash-Sutcliffe efficiency(NSE)≥0.68, –25%≤percent bias(PBIAS)≤25% and ratio of standard deviation(RSR)≤0.56) is 177 for the Default model and 1945 for the WUS-SWCM model. Also, the average Kling–Gupta efficiency(KGE) of acceptable calibration runs for the WUS-SWCM model is higher in both calibration and validation periods. When WUSs and SWCMs are implemented, surface runoff(between 30% and 99%) and water yield(between 0 and 18%) decreased in all sub-basins. Moreover, SWCMs lead to a higher contribution of groundwater flow to the channel and compensate for the extracted water by WUSs from the shallow aquifer. In summary, implementing WUSs and SWCMs in the SWAT model enhances model plausibility significantly.

关键词： SWAT model stream flow Wadis multi-metric framework water use systems soil and water conservation measures Halilrood Basin

Pressure distributions generated by vaporizing metal foils

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Transactions of Nonferrous Metals Society of China 2018年第10期28卷 2062-2074页

作者： Sheng CAI Department of Vehicle Engineering College of EngineeringChina Agricultural UniversityBeijing 100083China

The pressure distributions generated by vaporizing metal foils were *** analytical model which described the dynamic mechanical behavior of a rectangular plate under an impulsive loading was *** formed parts of free bulging tests were analyzed using the optical measurement *** measurement methods for pressure distributions were introduced and *** the perforated sheet forming test and the pressure film were found to be effective method to measure pressure *** cost of perforated sheet forming test was cheap and the pressure film was easy to *** different pressure distributions were measured and discussed,namely single pressure distribution,tailored pressure distribution and double-direction pressure *** three pressure distributions could be applied in different metal forming processes.

关键词： pressure distribution vaporizing foils sheet metals impulse forming

A Framework for the Systematic Design of Hybrid Separation Processe

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Chinese Journal of Chemical Engineering 2008年第3期16卷 333-342页

作者： Wolfgang Marquardt Sven Kossack Korhjnian Kraemer Process Systems Engineering and Center for Computational Engineering Science RWTH Aachen University D-52064 Aachen Germany

The design of optimal separation flow sheets for multi-component mixtures is still not a solved problem This is especially the case when non-ideal or azeotropic mixtures or hybrid separation processes are considered. We review recent developments in this field and present a systematic framework for the design of separation flow sheets. This framework proposes a three-step approach. In the first step different flow sheets are generated. In the second step these alternative flow sheet structures are evaluated with shortcut methods. In the third step a rigorous mixed-integer nonlinear programming （MINLP） optimization of the entire flow sheet is executed to determine the best alternative. Since a number of alternative flow sheets have already been eliminated, only a few optimization runs are necessary in this final step. The whole framework thus allows the systematic generation and evaluation of separation processes and is illustrated with the case study of the separation of ethanol and water.

关键词： process synthesis distillation design rectification body method mixed-integer nonlinear programming