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Does ash dieback affect the reproductive ecology of Fraxinus excelsior L.?

Journal of Forestry Research 2024年第2期35卷 54-69页

作者： Anna‑Katharina Eisen Lisa Buchner barbara Fussi Susanne Jochner‑Oette Physical Geography/Landscape Ecology and Sustainable Ecosystem Development Catholic University of Eichstätt-Ingolstadt85072 EichstättGermany Bavarian Office for Forest Genetics(AWG) 83317 TeisendorfGermany

Forest tree species reproduction is a key factor in maintaining the genetic diversity of future generations and the stability of forest *** ongoing ash dieback disease could affect the reproductive ecology of Fraxinus excelsior *** have a major impact on the quantity and quality of pollen and *** this study,we investigated pollen production and viability of pollen and seeds of ash trees with different health status from 2018 to *** were collected from 105 trees(pollen production),pollen from 125 trees(pollen viability),and seeds from 53 trees(seed quality)in two seed orchards and in one floodplain forest in southern *** all parameters were examined at every site every *** average pollen production per tree was estimated at 471.2±647.9 billion pollen *** addition,we found that a high number of inflorescences did not equate to high pollen production per *** production of healthy and diseased trees did not differ significantly,although only 47%of severely diseased male trees(vs.72%for healthy trees)produced *** regards to pollen viability,the TTC test showed an average viability of 73%±17%.Overall,there was a slight tendency for diseased trees to have less viable ***,a significant difference could only be calculated for trees in the floodplain *** percentage of germinable seeds in 2018 was 38%in the floodplain forest and 57%in one of the seed *** percentage of viable seeds(TTC test)ranged from 17 to 22%in the orchards in ***-viable seeds were usually heavily infested by *** general,seed quality was not significantly different between healthy and diseased *** results indicate that ash dieback affects flower formation and pollen viability but not pollen production or seed ***,the fact that hardly any flowering was observed,especially for trees that were seriously affected,suggests a negative effect of ash dieback on reproductive per

关键词： Common ash Seed orchard Floodplain forest Pollen production Viability TTC test Seed stratification Phenology

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DIVORCE AND KIDS

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中国翻译 1994年第3期 60-61页

作者： barbara Dafoe Whitehead

Divorce is transforming the lives ofAmerican children. In the post-World WarⅡ generation, more than 80 percent ofchildren grew up with both biologicalparents. Today only half will do so. Eachyear more than a million children experiencefamily breakup; about as many are born outof wedlock. At the same time, the problemsassociated with family disruption havegrown. Over-all child well-being hasdeclined, despite historically high publicspending. The teen suicide rate has almosttripled. Juvenile crime has increased

关键词： more than DIVORCE AND KIDS

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Pacing and predictors of performance during cross-country skiing races:A systematic review

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Journal of Sport and Health Science 2018年第4期7卷 381-393页

作者： Thomas Stogg barbara Pellegrini Hans-Christer Holmberg Department of Sport and Exercise Science University of SalzburgHallein/Rif 5400Austria CeRiSM Research Centre＂Sport Mountainand Health＂Rovereto 36068Italy Department of Neuroscience Biomedicine and MovementUniversity of VeronaVerona 37100Italy Swedish Winter Sports Research Centre Mid Sweden UniversityOstersund 83128Sweden School of Sport Sciences UiT Arctic University of NorwayTroms（）9037Norway School of Kinesiology University of British ColumbiaVancouverBC V6T 121Canada Department of Physiology and Pharmacology Karolinska InstitutetStockhol 17177Sweden Corresponding author.E-mail address：thomas.stoeggl@sbg.ac.at

Background： Cross-country skiing （XCS） racing, a popular international winter sport, is complex and challenging from physical, technical, and tactical perspectives. Despite the vast amount of research focusing on this sport, no review has yet addressed the pacing strategies of elite XCS racers or the factors that influence their performance. The aim was to review the scientific literature in an attempt to determine the effects of pacing strategy on the performance of elite XCS racers. Methods： Four electronic databases were searched using relevant subject headings and keywords. Only original research articles published in peerreviewed journals and the English language and addressing performance, biomechanics, physiology, and anthropometry of XCS racers were reviewed. Results： All 27 included articles applied correlative designs to study the effectiveness of different pacing strategies. None of the articles involved the use of an experimental design. Furthermore, potential changes in external conditions （e.g.,weather, ski properties） were not taken into consideration. A comparable number of studies focused on the skating or classical technique. In most cases, positive pacing was observed, with certain indications that higher-level athletes and those with more endurance and strength utilized a more even pacing strategy. The ability to achieve and maintain a long cycle length on all types of terrain was an important determinant of performance in all of the included studies, which was not the case for cycle rate. In general, uphill performance was closely related to overall race performance, with uphill performance being most closely correlated to the success of female skiers and performance on flat terrain being more important for male skiers. Moreover, pacing was coupled to the selection and distribution of technique during a race, with faster skiers employing more double poling and kick double poling, less diagonal stride, and more V2 （double dance） than V1 （single d

关键词： Classic style Competition Cycle characteristics Positive pacing Skating

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Step it up： Promoting physical activity in school-aged children and adolescents in China

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Journal of Sport and Health Science 2017年第4期6卷 386-387页

作者： barbara E. Ainsworth School of Nutrition and Health Promotion Arizona State University Phoenix AZ 85004 USA

In this special issue of the Journal of Sport and Health Science, a series of articles describe the results of the 2016 Physical Activity and Fitness in China--The Youth Study. The results show a relatively high prevalence of sedentary behaviors, unhealthy weight, lower fitness levels, and lower levels of engagement in physical exercise and fitness activities than antici- pated.

关键词： physical activity school-aged children

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A novel paradigm for feedback control in LPBF:layer-wise correction for overhang structures

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Advances in Manufacturing 2022年第2期10卷 326-344页

作者： Ema Vasileska Ali Gokhan Demir Bianca Maria Colosimo barbara Previtali Department of Mechanical Engineering Polytechnic University of MilanVia La Masa 120156 MilanItaly

In laser powder bed fusion(LPBF),it is common practice to select process parameters to achieve high density parts starting from simple geometries such as cubes or ***,additive manufacturing is usually adopted to producevery complex geometries,where parameters should be tuned locally,depending on the local features to be *** fact,geometrical features,such as overhangs,acute corners,and thin walls may lead to over-or under-heating conditions,which may result in geometrical inaccuracy,high roughness,volumetric errors(i.e.,porosity)oreven job failure due to *** work proposes a layer-wise control strategy to improve the geometrical precision of overhanging regions using a coaxial melt pool monitoring *** meltpool images acquired at each layer are used in a controlloop toadapt theprocess parameters locally at the next layer in order to minimize surface *** particular,the laser duty cycle is used as a controllable parameterto correct the energy *** work presents the main architecture of the proposed approach,the control strategy and the experimental procedure that need to be applied to design the control *** layer-wise control strategy was tested on AISI 316L stainless steel using an open LPFB *** results showed that the proposed layer-wise control solution results in a constant melt pool observed via the laser heated area size starting from the second layer onward,leading to a significant improvement in the geometrical accuracy of 5 mm-long bridge geometries.

关键词： Closed-loop control Melt pool monitoring:Defect correction Pulsed-wave emission

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Efficient and sustainable V-catalyzed oxidative desulfurization of fuels assisted by ionic liquids

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燃料化学学报 2018年第9期46卷 1121-1129页

作者： Alessia Coletti Federica Sabuzi barbara Floris Pierluca Galloni Valeria Conte Department of Chemical Science and Technologies University of Rome Tor Vergatavia della Ricerca Scientifica sncRome 00133Italy BT-InnoVaChem srl Academic Spin-Offc/o University of Rome Tor Vergatavia della Ricerca Scientifica sncRome 00133Ita

Fuel desulfurization is an appealing topic for the chemical industry since severe environmental regulations regarding SO_2 emissions have been legislated in many countries. In order to reduce the amount of sulfur-containing compounds in fuels,responsible for high SO_x emission levels,a green chemistry approach is compulsory. In this paper,vanadium salen and salophen complexes were used in the oxidation of a model aromatic sulfide,such as dibenzothiophene( DBT),in the presence of H_2O_2 as green oxidant. The oxidative process was successfully coupled with the extraction of the oxidized compounds by ionic liquids. The system resulted highly selective for sulfide oxidation,showing poor reactivity toward the oxidation of alkenes and allowing a significant reduction of S content in a model benzine. To note,the use of microwave in place of standard heating allowed to obtain 98% of DBT oxidation and almost complete sulfur extraction in the model fuel in 1000 s. For these reasons,this system was considered an easy,rapid and clean process to achieve fuel desulfurization.

关键词： fuel desulfurization V-catalysis sustainability ionic liquids microwaves

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β-Estradiol 17-acetate enhances the in vitro vitality of endothelial cells isolated from the brain of patients subjected to neurosurgery

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Neural Regeneration Research 2023年第2期18卷 389-395页

作者： Sonia Guzzo Pasquale De Bonis barbara Pavan Luciano Fadiga Department of Neuroscience and Rehabilitation Section of PhysiologyUniversity of FerraraFerraraItaly Center for Translational Neurophysiology of Speech and Communication(CTNSC) Italian Institute of Technology(IIT)FerraraItaly Department of Translational Medicine and for Romagna University of FerraraFerraraItaly

In the current landscape of endothelial cell isolation for building in vitro models of the blood-brain barrier,our work moves towards reproducing the features of the neurovascular unit to achieve glial compliance through an innovative biomimetic coating technology for brain chronic *** hypothesized that the autologous origin of human brain mic rovascular endothelial cells(hBMECs)is the first requirement for the suitable coating to prevent the glial inflammato ry response trigge red by foreign *** re,this study established a new procedure to preserve the in vitro viability of hBMECs isolated from gray and white matter specimens taken from neurosurge ry *** adult hBMECs is generally considered a challenging task due to the difficult survival ex vivo and progressive reduction in proliferation of these *** addition of 10 nMβ-estradiol 17-acetate to the hBMEC culture medium was found to be an essential and discriminating factor promoting adhesion and proliferation both after isolation and thawing,suppo rting the well-known protective role played by estrogens on *** particular,β-estradiol 17-acetate was critical for both freshly isolated and thawed female-derived hBMECs,while it was not necessary for freshly isolated male-derived hBMECs;however,it did countera ct the decay in the viability of the latter after *** tumo r-free hBMECs were thus cultured for up to 2 months and their growth efficiency was assessed befo re and after two periods of *** pite the thermal stress,the hBMECs remained viable and suitable for re-freezing and storage for several *** approach increasing in vitro viability of hBMECs opens new perspectives for the use of cryopreserved autologous hBMECs as biomimetic therapeutic tools,offering the potential to avoid additional surgical sampling for each patient.

关键词： β-estradiol 17-acetate 17β-estradiol cryopreservation gender-specific gray matter human brain microvascular endothelial cells surgical resections vascular protection white matter

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Commentary on "The BRICS Council of Exercise and Sport Science(BRICSCESS)——A new era has dawned" that has been published on JSHS

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Journal of Sport and Health Science 2019年第6期8卷 505-506页

作者： barbara E.Ainsworth College of Health Solutions Arizona State University School ofKinesiology Shanghai University of Sport

In 2018,the Journal of Sport and Health Science published an opinion article by Uvinha et all that introduced the readers to the BRICS Council of Exercise and Sport Science(BRICSCESS).BRICS is an acronym coined in 201... 详细信息

关键词： BRICS letter Sport

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Optical properties of silica sol-gel materials singly- and doubly-doped with Eu^3＋and Gd^3＋ ions

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Journal of Rare Earths 2016年第8期34卷 786-795页

作者： Natalia Pawlik barbara Szpikowska-Sroka Marta Soltys Wojciech A. Pisarski Institute of Chemistry University of Silesia 9 Szkolna Street 40-007 Katowice Poland

In present work, the optical and structural properties of silica sol-gel glasses and glass-ceramic materials singly- and dou- bly-doped with Eu3＋ and Gd3＋ ions were investigated. The optical properties of studied systems were determined based on absorption, excitation and emission spectra as well as luminescence decay analysis. Conducted studies clearly indicated a significant enhance- ment of visible emission originated from Eu3＋ ions as a result of changing the excitation mechanism, via Gd3＋Eu3＋ energy transfer. The luminescence intensity R-ratio was analyzed before and after heat-treatment process upon excitation at λex=393 nm and λex=273 nm. Moreover, the influence of excitation wavelength on luminescence decay time of the 5D0 excited state was also analyzed. The GdS＋-Eu3＋ energy transfer efficiencies for precursor and annealed samples were calculated based on luminescence lifetime of the 6p7/2 level of Gd3＋ ions. The X-ray diffraction measurements were conducted to verify the nature of obtained sol-gel materials. In re- sult, the formation of orthorhombic GdF3 nanocrystal phase dispersed in amorphous silica glass host was identified after annealing. Obtained results clearly indicated an incorporation of Eu3＋ activators into formed GdF3 nanocrystals. Thus, conducted heat-treatment process led to considerable changes in surrounding environment around Eu3＋ ions. Actually, it was found that en- ergy transfer phenomenon and heat-treatment process were responsible for significant improvement of Eu3＋ luminescence in stud- ied sol-gel samples.

关键词： nanocrystals sol-gel method luminescence rare earths

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Innovation in geoprocessing for a Digital Earth

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International Journal of Digital Earth 2018年第1期11卷 3-6页

作者： barbara Hofer Carlos Granell Lars Bernard Interfaculty Department of Geoinformatics-Z_GIS University of SalzburgSalzburgAustria Geospatial Technologies Research Group(GEOTEC) Universitat Jaume ICastellón de la PlanaSpain Chair of Geoinformatics Technische Universität DresdenDresdenGermany

Online geoprocessing,the provision and the use of spatial analysis functionality on the Web,is a powerful technological approach to fully realise the vision of a Digital *** Digital Earth objectives include the integration of information across diverse domains in order to address environmental and societal challenges as well as the interactive and exploratory provision of information to a wide audience(Craglia et al.2008).

关键词： interactive Earth Web

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