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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

Metrically measuring liver biopsy:A chronic hepatitis B and C computer-aided morphologic description

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World Journal of Gastroenterology 2008年第48期14卷 7335-7344页

作者： Nicola Dioguardi Fabio Grizzi barbara Fiamengo Carlo Russo Laboratories of Quantitative Medicine Istituto Clinico Humanitas IRCCS Department of Pathology Istituto Clinico Humanitas IRCCS

AIM： To describe a quantitative analysis method for liver biopsy sections with a machine that we have named ＂Dioguardi Histological Metriser＂ which automatically measures the residual hepatocyte mass （including hepatocytes vacuolization）, inflammation, fibrosis and the loss of liver tissue ***： We analysed digitised images of liver biopsy sections taken from 398 patients, The analysis with Dioguardi Histological Metriser was validated by comparison with semi-quantitative scoring ***： The method provides：（1） the metrical extension in two-dimensions （the plane） of the residual hepatocellular set, including the area of vacuoles pertinent to abnormal lipid accumulation; （2） the geo- metric measure of the inflammation basin, which distinguishes intra-basin space and extra-basin dispersed parenchymal leukoo/tes; （3） the magnitude of collagen islets, （which were considered truncated fractals and classified into three degrees of magnitude）; and （4） the tectonic index that quantifies alterations （disorders） in the organization of liver tissue. Dioguardi Histological Metriser machine allows to work at a speed of 0.1 mm^2/s, scanning a whole section in 6-8 ***： The results are the first standardized metrical evaluation of the geometric properties of the parenchyma, inflammation, fibrosis, and alterations in liver tissue tectonics of the biopsy sections. The present study confirms that biopsies are still valuable, not only for diagnosing chronic hepatitis, but also for quantifying changes in the organization and order of liver tissue structure.

关键词： Liver measurement Image analysis Liverlesion Liver tectonics

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

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

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

Vascular architecture:is it a helpful histopathological biomarker for hepatocellular carcinoma?

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2007年第4期8卷 217-220页

作者： GRIZZI Fabio FRANCESCHINI barbara FIAMENGO barbara RUSSO Carlo DIOGUARDI Nicola Laboratories of Quantitative Medicine Istituto Clinico Humanitas IRCCS20089 RozzanoMilanItaly Department of Pathology Istituto Clinico Humanitas IRCCS20089 RozzanoMilanItaly

Hepatocellular carcinoma(HCC) remains one of the major public health problems throughout the *** originally associated with tumorigenic processes,liver angiogenesis has also been observed in the context of different liver in-flammatory,fibrotic,and ischemic *** we investigate the fractal dimension as a quantitator of non-Euclidean two-dimensional vascular geometry in a series of paired specimens of primary HCC and surrounding non-tumoral tissue,and discuss why this parameter might provide additional information regarding cancer *** application of fractal geometry to the measurement of liver vascularity and the availability of a computer-aided quantitative method can eliminate errors in visual interpretation,and make it possible to obtain closer-to-reality numerals that are compulsory for any measurement process.

关键词： Liver Angiogenesis Cancer Fractals Geometry Biomarkers

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

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

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