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Influence of soil and microclimate on species composition and grass encroachment in heath succession

Journal of Plant Ecology 2012年第3期5卷 249-259页

作者： Jasmin Mantilla-Contreras jens Schirmel Stefan Zerbe Department of Landscape Ecology Institute of Botany and Landscape EcologyUniversity of GreifswaldGrimmerstrasse 88D-17487 GreifswaldGermany Biological Station of Hiddensee University of GreifswaldBiologenweg 15D-18565 Isle of HiddenseeGermany Faculty of Science and Technology Free University of BolzanoPiazza Universita`5I-39100 Bozen-BolzanoItaly

Aims and Methods Mostly due to land use changes,European heathlands have become increasingly *** addition,the increasing amount of atmospheric nitrogen deposition has resulted in an encroachment of grasses and a loss in species *** many investigations,information about the precise environmental parameters that determine the development and maintenance of heathland vegetation is still *** order to determine the environmental factors that control heath succession and grass encroachment,and to develop appropriate management schemes,we studied the influence of several soil and microclimate parameters on species composition and vegetation characteristics in five successional stages in a coastal heathland on the island of Hiddensee,north-east Germany,where the encroachment of Carex arenaria has become a major *** Findings We recorded the highest plant species richness in grey dune and birch forest plots,while the encroachment of *** let to a significant decline in plant species *** most important environmental factors influencing species richness and distribution of single species were microclimate,soil moisture,soil pH and the C/N *** many studies reported the importance of differences in nutrient availability,we found no significant correlations between soil nutrient availability and vegetation *** conditions in dense *** stands,especially soil properties(*** pH),showed great differences in comparison to the other successional ***,no correlations between the encroachment of *** and single environmental factors were *** results show that not only soil nutrients are important abiotic factors in heaths but that also microclimate and soil moisture play an important role and that many factors are involved in heath succession and in the promotion of grass *** plans for the conservation and restoration of heathlands should therefore focu

关键词： biodiversity Carex arenaria heathland conservation N deposition restoration tall grasses

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Effect of a 26-month floorball training on male elderly's cardiovascular fitness, glucose control, body composition, and functional capacity

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Journal of Sport and Health Science 2018年第2期7卷 149-158页

作者： Mogens Theisen Pedersen Jacob Vorup jens Bangsbo Copenhagen Centre of Team Sport and Health Department of NutritionExercise and SportsSection of Integrated PhysiologyUniversity of Copenhagen Health Science Research Center University College Lillebaelt

Background: Floorball training offers a motivating and socially stimulating team activity for older adults, and 12 weeks of floorball training twice a week among men aged 65—76 years have been shown to have positive effects on a number of physiological parameters important for health. However, the effect of long-term participation in floorball training among male elderly has not been investigated. The aim of the present study was to examine the effect of 26-month self-organized regular participation in floorball training on cardiovascular fitness, body composition, blood lipids, glucose control, and physical function among recreationally active men aged 66—78 ***: After completing a 12-week randomized and controlled intervention with floorball and petanque training in the autumn 2014 or spring2015, 15 subjects chose to participate in floorball training(floorball group, FG), whereas 16 subjects resumed their usual lifestyle(control group,CG). FG took part in self-organized floorball training 1.7 sessions of 40 min/week, and CG continued their normal recreationally active lifestyle during a 26-month follow-up period. At baseline and after the follow-up period subjects were tested for cardiovascular fitness, glucose control(resting blood samples), body composition dual-energy X-ray absorptiometry(DXA-scanning), and functional ***: In FG, the decline in maximal oxygen uptake(VO_(2max)) during the follow-up period was lower(242 ± 379 mL/min, p = 0.01), blood glycosylated hemoglobin(HbA1c) increased less(—1.6 ± 2.9 mmol/L, p = 0.02), and leg bone mineral density increased more(0.03 ± 0.05 g/cm^2,p = 0.02) than those in CG. The effects on body mass, total lean body mass, fat mass, blood lipids, and physical function were similar in FG and ***: Approximately twice weekly floorball sessions with 40 min/session over 26-month appear to reduce age-related decline in cardiovascular fitness and glucose control and improve leg bone mineral density,

关键词： Bone mineral density Elderly Floorball Glucose control VO2max

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Expression of fungal biosynthetic gene clusters in S. cerevisiae for natural product discovery

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Synthetic and Systems Biotechnology 2021年第1期6卷 20-22页

作者： Zihe Liu Zhenquan Lin jens Nielsen College of Life Science and Technology Beijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University of Chemical Technology100029BeijingChina Department of Biology and Biological Engineering Chalmers University of TechnologySE41296GothenburgSweden Novo Nordisk Foundation Center for Biosustainability Technical University of DenmarkDK2800LyngbyDenmark BioInnovation Institute Ole Maaløes Vej 3DK2200Copenhagen NDenmark

Fungi are well known for production of antibiotics and other bioactive secondary metabolites,that can be served as pharmaceuticals,therapeutic agents and industrially useful ***,compared with the characterization of prokaryotic biosynthetic gene clusters(BGCs),less attention has been paid to evaluate fungal *** is partially because heterologous expression of eukaryotic gene constructs often requires replacement of original promoters and terminators,as well as removal of intron sequences,and this substantially slow down the workflow in natural product *** is therefore of interest to investigate the possibility and effectiveness of heterologous expression and library screening of intact BGCs without refactoring in industrial friendly microbial cell factories,such as the yeast Saccharomyces ***,we discuss the importance of developing new research directions on library screening of fungal BGCs in yeast without refactoring,followed by outlooking prominent opportunities and challenges for future advancement.

关键词： Natural product discovery Cross-species engineering Spliceosome High-throughput BGC cloning Synthetic biology Yeast

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Implementation of an in-house flow cytometric analysis of DNA fragmentation in spermatozoa

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Asian Journal of Andrology 2020年第3期22卷 246-251页

作者： Anne Sofie Rex Chunsen Wu Jorn Aagaard jens Fedder Centre of Andrology and Fertility Clinic Odense University HospitalOdense 5000Denmark Aagaard Gynaecological Clinic Skejby 8200AarhusDenmark Research Unit of Gynaecology and Obstetrics Faculty of HealthUniversity of Southern DenmarkOdense 5000Denmark.

An increased amount of DNA fragme ntation in the spermatozoa(SDF)is linked to male in *** Sperm Chromati n Structure Assay(SCSA)is widely used for analysis of ***,the current software(SCSASoftR)linked to this assay is licensed and often located within larger diagnostic *** this study,we present a protocol for using other types of software than SCSASoftR to determine the SDF index(DFI)with clinical *** protocol is engineered after collect!ng and analyzing 254 samples from fertility patients and sperm donors over a 15-month *** is analyzed using a strict protocol where the spermatozoa are treated with a strong acid(pH 1.2)followed by acridine *** is determined by a standard flow cytometric software,FACSDiva *** of the outcome of the fertility treatment is included for 137 patients receiving either intrauterine inseminations(IUI)or timed coitus(TC).The results show that the chance of pregnancy decli nes as DFI in *** also found that the male DFI affects the chanee of pregnancy independent of the female *** have shown that a standard flow cytometric software can be used when determi ning a clinical releva nt *** findings are a sign ificant step toward impleme nting the an alysis as a part of the routi ne,in・house diag no sing of the male fertility patient and subseque ntly optimizing the treatme nt course of the couple with reduced human and financial costs.

关键词： DNA fragme ntation flow cytometry in-house an alysis in trauteri ne in semi natio n Sperm Chromati n Structure Assay spermatozoa

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High temperature tribological behaviour of PVD coated tool steel and aluminium under dry and lubricated conditions

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Friction 2021年第4期9卷 802-821页

作者： Justine DECROZANT-TRIQUENAUX Leonardo PELCASTRE Cedric COURBON Braham PRAKASH jens HARDELL Division of Machine Elements Lulea University of TechnologySE-97187Sweden Universite de Lyon CNRSEcole Nationale d'lngenieurs de Saint-EtienneLTDS UMR5513F-42023France Department of Mechanical Engineering Tsinghua UniversityBeijing100084 China

Aluminium alloys are commonly used as lightweight materials in the automotive *** non-ferrous family of metallic alloys offers a high versatility of properties and *** reduce weight and improve safety,high strength-to-weight ratio alloys(e.g.6XXX and 7XXX),are increasingly implemented in ***,these alloys exhibit low formability and experience considerable springback during cold forming,and are therefore hot *** forming,severe adhesion(***)of aluminium onto the die surface takes *** phenomenon has a detrimental effect on the surface properties,geometrical tolerances of the formed parts and maintenance of the *** effect of surface engineering as well as lubricant chemistry on galling has not been sufficiently ***-like carbon(DLC)and CrN physical vapour deposition(PVD)coated steel have been studied to reduce aluminium ***,the interaction between lubricants and PVD coatings during hot forming of aluminium alloys is not yet fully *** present study thus aims to characterise the high temperature tribological behaviour of selected PVD coatings and lubricants during sliding against aluminium *** objectives are to first select promising lubricant-coating combinations and then to study their tribological response in a high-temperature reciprocating friction and wear *** and lubricated tests were carried out at 300℃ using a commercial polymer *** using DLC,CrN,CrTiN,and CrAIN coated tool steel were compared to uncoated tool steel reference *** initial and worn test specimen surfaces were analysed with a 3-dimensional(3D)optical profiler,scanning electron microscope(SEM)and energy dispersive X-ray spectroscope(EDS)as to understand the wear *** results showed formation of tribolayers in the contact zone,reducing both friction and *** stability of these layers highly depends on both the coatings'roughness and chemical affinity towards

关键词： high temperature tribology aluminium lubrication physical vapour deposition(PVD)coatings material transfer adhesion

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Second harmonic generation spectroscopy on hybrid plasmonic/dielectric nanoantennas

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Light(Science & Applications) 2016年第1期5卷 803-809页

作者： Heiko Linnenbank Yevgen Grynko jens Förstner Stefan Linden Physikalisches Institut Rheinische Friedrich-Wilhelms Universität BonnBonn 53115Germany Department of Electrical Engineering Universität PaderbornPaderborn 33102Germany

Plasmonic nanoantennas provide unprecedented opportunities to concentrate light fields in subwavelength-sized *** placing a nonlinear dielectric nanoparticle in such a hot spot,one can hope to take advantage of both the field enhancement provided by nanoantennas and the large,nonlinear optical susceptibility of dielectric *** test this concept,we combine gold gap nanoantennas with second-order,nonlinear zinc sulfide nanoparticles,and performsecond harmonic generation(SHG)spectroscopy on the combined hybrid dielectric/plasmonic nanoantennas as well as on the individual *** find that SHG from the bare gold nanoantennas,even though it should be forbidden due tosymmetry reasons,is several orders ofmagnitude larger than that of the bare zinc sulfide *** stronger second harmonic signals are generated by the hybrid dielectric/plasmonic *** experiments with nanoantennas containing linear lanthanumfluoride nanoparticles reveal;however,that the increasedSHG efficiency of the hybrid dielectric/plasmonic nanoantennas does not depend on the nonlinear optical susceptibility of the dielectric nanoparticles but is an effect of the modification of the dielectric *** combination of a hybrid dielectric/plasmonic nanoantenna,which is only resonant for the incoming pump light field,with a second nanoantenna,which is resonant for the generated second harmonic light,allows for a further increase in the efficiency of *** the second nanoantenna mediates the coupling of the second harmonic light to the far field,this double-resonant approach also provides us with control over the polarization of the generated light.

关键词： nanoantennas plasmonics second harmonic generation

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Wear dependent virtual flow rate sensor for progressing cavity pumps with deformable stator

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Petroleum Science 2024年第2期21卷 1346-1353页

作者： jens Müller Sebastian Leonow Johannes Schulz Christian Hansen Martin Monnigmann Ruhr-Universitat Bochum Universit atsstraûe 150Bochum44801Germany SEEPEX GmbH Scharnh olzstraûe 344Bottrop46240Germany

This contribution presents a novel wear dependent virtual flow rate sensor for single stage single lobe progressing cavity pumps. We study the wear-induced material loss of the pump components and the impact of this material loss on the volumetric efficiency. The results are combined with an established backflow model to implement a backflow calculation procedure that is adaptive to wear. We use a laboratory test setup with a highly abrasive fluid and operate a pump from new to worn condition to validate our approach. The obtained measurement data show that the presented virtual sensor is capable of calculating the flow rate of a pump being subject to wear during its regular operation.

关键词： Backflow Progressing cavity pump Virtual sensor Wear

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Persistent organic pollutants and male reproductive health

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Asian Journal of Andrology 2014年第1期16卷 71-80页

作者： Anne Vested Aleksander Giwercman jens Peter Bonde Gunnar Toil- Department of Occupational Medicine Danish Ramazzini Centre Aarhus University Hospital Aarhus Denmark Reproductive Medicine Centre Lund University Skane University Hospital Malm6 Sweden Department of Occupational and Environmental Medicine Bispebjerg Hospital of Copenhagen University

Environmental contaminants such as persistent organic pollutants （POPs） are man-made bioaccumulative compounds with long half-lives that are found throughout the world as a result of heavy use in a variety of consumer products during the twentieth century. Wildlife and animal studies have long suggested adverse effects of exposure to these compounds on human reproductive health, which, according to the endocrine disrupter hypothesis, are ascribed to the compounds＇ potential to interfere with endocrine signaling, especially when exposure occurs during certain phases of fetal and childhood development. An extensive number of epidemiological studies have addressed the possible effects of exposure to POPs on male reproductive health, but the results are conflicting. Thus far, most studies have focused on investigating exposure and the different reproductive health outcomes during adulthood. Some studies have addressed the potential harmful effects of fetal exposure with respect to malformations at birth and/ or reproductive development, whereas only a few studies have been able to evaluate whether intrauterine exposure to POPs has long-term consequences for male reproductive health with measurable effects on semen quality markers and reproductive hormone levels in adulthood. Humans are not exposed to a single compound at a time, but rather, to a variety of different substances with potential divergent hormonal effects. Hence, how to best analyze epidemiological data on combined exposures remains a significant challenge. This review on POPs will focus on current knowledge regarding the potential effects of exposure to POPs during fetal and childhood life and during adulthood on male reproductive health, including a critical revision of the endocrine disruption hypothesis, a comment on pubertal development as part of reproductive development and a comment on how to account for combined exposures in epidemiological research.

关键词： endocrine disruption male reproduction persistent organic compounds reproductive hormones semen quality

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Social and Ecological Constraints on Decision Making by Transhumant Pastoralists: A Case Study from the Moroccan Atlas Mountains

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Journal of Mountain Science 2012年第3期9卷 307-321页

作者： Zakia AKASBI jens OLDELAND Jürgen DENGLER Manfred FINCKH Biodiversity Evolution and Ecology of PlantsBiocentre Klein Flottbek and Botanical GardenUniversity of HamburgOhnhorststr.1822609 HamburgGermany Institut Agronomique et Vétérinaire Hassan II B.P.6202 les instituts10000-RabatMorocco

Transhumant pastoralism is an important activity in southern Morocco. Migration pattern of transhumant pastoralists can be affected by physical factors (e.g. droughts and diseases) or socioeconomic factors (e.g. schooling options for children and migration costs). We studied the spatio-temporal rangeland usage of the three tribes Ait Mgoun, Ait Zekri, and Ait Toumert in the south-central Atlas region with a two-fold approach. First, we tracked the migration movements of one representative transhumant herd using the Advanced Research and Global Observation Satellite (ARGOS) collars, which record coordinates from satellite signals. Second, we interviewed herders to obtain information about general grazing practices of the respective tribe and to gain more direct information on motivations underlying decisions. For each tribe we observed small-, medium- and large-scale movements. We found that the most important drivers of migration decisions were seasonal fodder availability and weather conditions in combination with herd-specific risk and cost assessment, as well as personal factors. In conclusion, general migration patterns vary in time, both between and within the tribes, but according to a regulatory framework. Moreover, it appears that both the customary rules and its flexible adaptation to physical constraints are generally beneficial in terms of conservation of the arid and semiarid rangeland resources.

关键词： Ait Mgoun Ait Zekri Ait Toumert ARGOS Goat grazing High Atlas Jebel Saghro Migration pattern Rangeland Small ruminant Transhumance

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Do birds in flight respond to(ultra)violet lighting?

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Avian Research 2017年第4期8卷 192-201页

作者： Roel May jens Astrom Oyvind Hamre Espen Lie Dahl Terrestrial Ecology Department Norwegian Institute for Nature Research(NINA)TrondheimNorway Steinoysund SmolaNorway.

Background: Concerns for bird collisions with wind turbines affect the deployment of onshore and offshore windpower *** avoid delays in consenting processes and to streamline the construction and operation phase,functional mitigation measures are required which efficiently reduces bird *** is the primary sensory system in birds,which for a number of species also includes the ultraviolet *** bird species that are known to collide with offshore wind turbines are sensitive in the violet or ultraviolet *** species that are mainly active at lower ambient light levels,lighting may deter birds from the lit ***(ultra)violet lights may in addition not disturb ***,we do not know whether UV-sensitive birds in flight actually respond behaviourally to UV ***: We therefore tested the efficacy of two types of lights within the violet(400 nm) and ultraviolet(365 nm) spectrum to deter birds from the lit *** lights were placed vertically and monitored continuously between dusk and dawn using an avian radar ***: Relative to control nights,bird flight activity(abundance) was 27% lower when the ultraviolet light was *** light resulted in a 12% decrease in overall abundance,and in addition,a vertical displacement was seen,increasing the average flight altitude by 7 *** temporal changes occurred,this effect persisted over the season below 40 m above sea ***: Although the results from this pilot study are promising,we argue there still is a long way to go before a potentially functional design to mitigate collisions that has proven to be effective in situ may be in place.

关键词： Avian radar Displacement Habituation Mitigation Seabirds Ultraviolet Wind turbine

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