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1.
Germán Carretero-Navarro Doménico Cherubini Wolfgang Taube 《European Journal of Sport Science》2019,19(5):595-602
Weighted vests are widely used to improve running economy and performance. However, it is not well-studied how running mechanics are adapted to counteract the higher peak vertical ground reaction forces (Fpeak) while running with such a device. Therefore, the present study aimed to investigate the effects of different loading conditions on running mechanics at different velocities. Thirteen subjects participated in two separate sessions one week apart. In the first session, maximal aerobic speed (MAS) was determined through a maximal incremental running test while in the second session, they were instructed to run during one minute under different loading (0%, +10% and +20% of body mass [BM]) and velocity (60%, 80% and 100% of MAS) conditions in a random order. Spatiotemporal data were recorded and then running mechanics modelled using the spring-mass model. The main results indicated that vertical and leg stiffness (Kvert and Kleg, respectively) were increased (P?.001) as velocity increased but remained unaltered (P?>?.05) when load was changed. At the same time, alterations of the running kinematics were observed such as longer contact times, reduced flight times, stride frequencies and step lengths, as well as an increase of the centre of mass dynamics. Based on these results it is assumed that runners maintain a certain stiffness level for each velocity despite different loading conditions. As a consequence, Fpeak increases and this probably causes spatiotemporal adjustments in the movement kinematics. 相似文献
2.
Edgardo Ferretti Leticia Cagnina Viviana Paiz Sebastián Delle Donne Rodrigo Zacagnini Marcelo Errecalde 《Information processing & management》2018,54(6):1169-1181
In this work, we present the first quality flaw prediction study for articles containing the two most frequent verifiability flaws in Spanish Wikipedia: articles which do not cite any references or sources at all (denominated Unreferenced) and articles that need additional citations for verification (so-called Refimprove). Based on the underlying characteristics of each flaw, different state-of-the-art approaches were evaluated. For articles not citing any references, a well-established rule-based approach was evaluated and interesting findings show that some of them suffer from Refimprove flaw instead. Likewise, for articles that need additional citations for verification, the well-known PU learning and one-class classification approaches were evaluated. Besides, new methods were compared and a new feature was also proposed to model this latter flaw. The results showed that new methods such as under-bagged decision trees with sum or majority voting rules, biased-SVM, and centroid-based balanced SVM, perform best in comparison with the ones previously published. 相似文献
3.
Fadhaa A. Ghafil Bassim I. Mohammad Hussain S. Al-Janabi Najah R. Hadi Hayder A. Al-Aubaidy 《Indian journal of clinical biochemistry : IJCB》2021,36(1):81
Genetic variation in the angiotensin II type 1 receptor (AT1R) has an important effect on the outcome of acute coronary syndrome (ACS) initiated treatment with captopril. This study aims to investigate the impact of genetic polymorphism of AT1R (rs5186 and rs275651) on the ACS outcome in Iraqi patients treated with captopril. A total of 250 Iraqi individuals with ACS were included in this case—control study and they were divided into two study groups; Study group 1 included 125 participants who were prescribed captopril, 25 mg twice daily and study group 2 included 125 participants who received no captopril as part of their ACS treatment (control study). The AT1R gene (rs5186) CC genotype was found to be associated with ST-elevation myocardial infarction (STEMI) (Odd’s ratio (O.R) = 1.2, P = 0.7), while AC was associated with Non-ST-elevation myocardial infarction (NSTEMI) and unstable angina (UA) (O.R = 1.2, P = 0.8). AC genotype is more prone to have Percutaneous coronary intervention (PCI) after ACS attack (O.R = 1.2, P = 0.6). CC genotype had a risk to get less improvement (O.R = 1.6, P = 0.5), so might require higher doses of captopril during acute coronary insult. The AT1R gene (rs275651) AA genotype was associated with UA (O.R = 1.3, P = 0.9). AA and AT genotypes were more prone to have PCI after ACS attack (O.R = 3.9 P = 0.2, O.R = 3.5, P = 0.3 respectively) and thus requiring higher doses of captopril. We conclude that the AT1R rs5186, rs275651 genetic polymorphisms might partially affect the clinical outcome of ACS patients treated with captopril and might have captopril resistance which requires higher doses. 相似文献
4.
Mirjam A. Twigt 《Popular Communication》2019,17(2):171-184
ABSTRACTFor many forcefully displaced people worldwide, notions around one’s sense of “home” and “place” in the world are perpetually unsettled. This article explores how digital technologies interact with embodied, material experiences within the geographical location refugees are residing in. Empirical examples from ethnographic research conducted among Iraqi urban refugees, living in prolonged uncertainty in Jordan, shows how situated experiences of legal, material, and social uncertainty reinforce particular mediated socialities. Pivotal studies have shown how digital connections engender virtual home-making practices and a wide variety of connected presences. This study points to the other side of the same coin: the cultivation of “absent presence.” “Absent presence” refers to feelings—the ambivalence that experiences of prolonged displacement bring about—but also to active disengagement and affective tactics in response. These engender a further separation from the physical world where forced migrants are not deemed welcome. 相似文献
5.
A. Miller 《Journal of Web Librarianship》2019,13(2):127-155
The emerging creative practices of digital collections are increasing in prominence thanks to the access to, and appeal of, data visualizations. Interactive data visualizations, such as a map, timeline, chart, graph, or artist’s rendering of data, enable users to pursue their own research interests within a collection and participate in new areas of research. Use of these data visualizations enhances the scope of the collection and enables a modern and diverse thematic collection to emerge. This article considers the question: Does the addition of data visualizations affect how users participate with a research collection? Impacts on collection development, application of user-centered design, and analysis of users’ exploratory strategies are discussed. Examples of data visualizations used in digital humanities projects and digital collections are presented as case studies. 相似文献
6.
Children are sensitive to a number of considerations influencing distributions of resources, including equality, equity, and reciprocity. We tested whether children use a specific type of reciprocity norm—market norms—in which resources are distributed differentially based strictly on amount offered in return. In two studies, 195 children 5–10 years and 60 adults distributed stickers to friends offering same or different amounts of money. Overall, participants distributed more equally when offers were the same and more unequally when offers were different. Although sensitive to why friends offered different amounts of money, children increasingly incorporated market norms into their distributions with age, as the oldest children and adults distributed more to those offering more, irrespective of the reasons provided. 相似文献
7.
8.
U. Casellato F. Fenzi P. Guerriero S. Sitran P. A. Vigato U. Russo M. Galgani M. Mendera A. Manasse 《Journal of Cultural Heritage》2003,4(4):337-353
A significant number of archaeological finds of the 13th–16th century from the Tuscan sites of Germagnana and Gambassi in Valdelsa—FI, was studied by different physico-chemical investigations (SEM–EDS, ICP, Mössbauer spectroscopy, XRD, XRF, TG-DTA) in order to contribute to clarify the production methodology and the pre-industrial glass manufacture technology. The studied samples are mainly non-vitreous finds as production waste, refractory materials, crucibles and raw materials; also vitreous finds as frits, skims, glasses (glass masses, glass working waste and finished products) have been taken into consideration. The obtained petrographic and physico-chemical data strongly suggest that both Gambassi and Germagnana glass manufactures were strictly connected with the sources of vitrifiable materials, situated in Tuscan sand quarries. In particular a comparison between sands from the neighbouring quarries and appropriate finds of the two archaeological sites evidences that the employed vitrifiable materials possibly belong to La Casina La Cava resort. The archaeological classification, based on macroscopic observation and stratigraphic position, was compared and verified with the scientific classification of the examined finds of Germagnana and Gambassi sites based on their composition, morphology and physico-chemical properties. 相似文献
9.
Edward A. Holdaway 《Higher Education Quarterly》1993,47(3):237-258
Many western countries are paying increasing attention to the organization and administration of graduate studies. Such attention has developed from primary concerns about completion times, completion percentages, programme quality, and student quality, as well as secondary concerns about supervisors, funding, coursework, inter-organizational co-operation, and policies and practices of both universities and research councils. Using information about British graduate programmes as a basis, the article presents policy issues related to research councils, funding councils, and control, followed by discussion of the themes of the nature of programmes, supervision and evaluation, completion time, quality, and innovation. The final sections address several concerns and offer some suggestions. 相似文献
10.