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Enhancing the Trustworthiness of 6G Based on Trusted Multi-Cloud Infrastructure:A Practice of Cryptography Approach
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作者 Mingxing Zhou Peng Xiao +3 位作者 Qixu Wang Shuhua Ruan Xingshu Chen Menglong Yang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期957-979,共23页
Due to the need for massive device connectivity,low communication latency,and various customizations in 6G architecture,a distributed cloud deployment approach will be more relevant to the space-air-ground-sea integra... Due to the need for massive device connectivity,low communication latency,and various customizations in 6G architecture,a distributed cloud deployment approach will be more relevant to the space-air-ground-sea integrated network scenario.However,the openness and heterogeneity of the 6G network cause the problems of network security.To improve the trustworthiness of 6G networks,we propose a trusted computing-based approach for establishing trust relationships inmulti-cloud scenarios.The proposed method shows the relationship of trust based on dual-level verification.It separates the trustworthy states of multiple complex cloud units in 6G architecture into the state within and between cloud units.Firstly,SM3 algorithm establishes the chain of trust for the system’s trusted boot phase.Then,the remote attestation server(RAS)of distributed cloud units verifies the physical servers.Meanwhile,the physical servers use a ring approach to verify the cloud servers.Eventually,the centralized RAS takes one-time authentication to the critical evidence information of distributed cloud unit servers.Simultaneously,the centralized RAS also verifies the evidence of distributed RAS.We establish our proposed approach in a natural OpenStack-based cloud environment.The simulation results show that the proposed method achieves higher security with less than a 1%system performance loss. 展开更多
关键词 6G multi-cloud trusted Infrastructure remote attestation commercial cipher
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The Global Stratotype Section and Point (GSSP) for the boundary between the Capitanian and Wuchiapingian Stage (Permian) 被引量:41
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作者 Yugan Jin Shuzhong Shen +5 位作者 Charles M. Henderson Xiangdong Wang Wei Wang Yue Wang Changqun Cao Qinghua Shang 《Episodes》 SCIE 2006年第4期253-262,共10页
The Global Stratotype Section and Point (GSSP) for the boundary between the Capitanian and Wuchiapingian stages, also the boundary between the Guadalupian and Lopingian Series is defined at the First Appearance Dat... The Global Stratotype Section and Point (GSSP) for the boundary between the Capitanian and Wuchiapingian stages, also the boundary between the Guadalupian and Lopingian Series is defined at the First Appearance Datum (FAD) of the conodont Clarkina postbitteri postbitteri at the base of Bed 6k in the Penglaitan Section along the Hongshui River in Guangxi Province, South China. This point is within a chronomorphocline from Clarkina postbitteri hongshuiensis to C. dukouensis and nearly coincides with the Middle-Upper Absaroka Megasequence boundary and as such is documented within a continuously deposited carbonate lowstand succession with deep-water facies of the Maokou Formation below and deep-water facies of the Heshan Formation above. Furthermore, this point also coincides with a major extinction of various Permian fossils including corals, fusulinaceans, ammonoids and brachiopods. The proximity to an apparently global major sequence boundary and extinction event will serve as a means of correlation of this GSSP into other regions in which the defining taxon is not present because of profound provincialism during the Middle and Upper Permian. Carbon isotopic trends and magnetostratigraphic signatures are also provided to help correlate this GSSP into other regions, including those with continental facies successions. The Tieqiao Section near the county town of Laibin is also described as a supplementary reference section. 展开更多
关键词 二叠纪 历史地质 同位素 全球层型解剖面和点
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A win-win technique of stabilizing sand dune and purifying paper mill black-liquor 被引量:15
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作者 WANG Hanjie Penning de Vries FRITS JIN Yongcan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第4期488-493,共6页
The principle and technique were reported here to produce lignin-based sand stabilizing material (LSSM) using extracted lignin from black liquor of straw paper mills. Field tests using LSSM to stabilize and green sa... The principle and technique were reported here to produce lignin-based sand stabilizing material (LSSM) using extracted lignin from black liquor of straw paper mills. Field tests using LSSM to stabilize and green sand dunes were started in 2002. The field experiment was carded out in August 2005 when the newly formed plant community was 3 years old. The results from the comprehensive field experiment demonstrated that unlike polyvinyl acetate or foamed asphalt commonly used for dune stabilization, LSSM was plant- friendly material and could be used in combination with seeding and planting of desert species. With the help of LSSM, the desert species (i.e., Agriophyllum squarrosum (L.) Moq. and Artemisia desertorum Spreng. etc.) could be used to form community in 2-3 yeas and to stabilize sand dune effectively. The newly formed community was sustainable under an extremely dry climate condition. The organic matter and total nitrogen in the soil increased significantly as the community were formed, while the change in P and K contents in the soil was negligible. 展开更多
关键词 climate change desertification control straw pulping black liquor purification
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MicroRNAs in heart and circulation during physical exercise 被引量:7
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作者 Lijun Wang Yicheng Lv +1 位作者 Guoping Li Junjie Xiao 《Journal of Sport and Health Science》 SCIE 2018年第4期433-441,共9页
Exercise training is beneficial to the cardiovascular system. MicroRNAs (miRNAs, miRs) are a class of conserved non-coding RNAs and play a wide-ranging role in the regulation of eukaryotic gene expression. Exercise ... Exercise training is beneficial to the cardiovascular system. MicroRNAs (miRNAs, miRs) are a class of conserved non-coding RNAs and play a wide-ranging role in the regulation of eukaryotic gene expression. Exercise training alters the expression levels of large amounts ofmiRNAs in the heart. In addition, circulating miRNAs appear to be regulated by exercise training. In this review, we will summarize recent advances in the regulation of miRNAs during physical exercise intervention in various cardiovascular diseases, including pathologic cardiac hypertrophy, myocardial fibrosis, ischemia-reperfusion injury, myocardial infarction, and heart failure. The regulatory role of circulating miRNAs after exercise training was also reviewed. In conclusion, miRNAs might be a valuable target for treatment of cardiovascular diseases and have great potential as biomarkers for assessment of physical performance.2018 Published by Elsevier B.V.on behalf of Shanghai University of Sport. This is an open access article under the CC BY-NC-ND license. (http://creativecommons.org/licenses/by-nc-nd/4.0/). 展开更多
关键词 Cardiovascular diseases Circulating microRNAs EXERCISE MICRORNAS
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The influence of physiobiomechanical parameters,technical aspects of shooting,and psychophysiological factors on biathlon performance:A review 被引量:6
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作者 Marko S.Laaksonen Thomas Finkenzeller +1 位作者 Hans-Christer Holmberg Gerold Sattlecker 《Journal of Sport and Health Science》 SCIE 2018年第4期394-404,共11页
The biathlon, an Olympic sporting discipline that combines cross-country skiing with rifle marksmanship, entails considerable physiological demands, as well as fine motor control while shooting after intense exercise ... The biathlon, an Olympic sporting discipline that combines cross-country skiing with rifle marksmanship, entails considerable physiological demands, as well as fine motor control while shooting after intense exercise and under mental pressure. Although much of our knowledge about cross-country skiing is probably also applicable to the biathlon, carrying the rifle and shooting under stress make this discipline somewhat unique. The present review summarizes and examines the scientific literature related to biathlon performance, with a focus on physiological and biomechanical factors and shooting technique, as well as psychophysiological aspects of shooting performance. We conclude with suggestions for future research designed to extend our knowledge about the biathlon, which is presently quite limited.2018 Published by Elsevier B.V. on behalf of Shanghai University of Sport. This is an open access article under the CC BY-NC-ND license. (http://creativecommons.org/licenses/by-nc-nd/4.0/). 展开更多
关键词 Cortical activity Gaze behavior Postural balance SKIING TRIGGERING
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Association of traditional Chinese exercises with glycemic responses in people with type 2 diabetes:A systematic review and meta-analysis of randomized controlled trials 被引量:5
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作者 Ge Song Changcheng Chen +3 位作者 Juan Zhang Lin Chang Dong Zhu Xueqiang Wang 《Journal of Sport and Health Science》 SCIE 2018年第4期442-452,共11页
Background: There is increasing evidence showing the health benefits of various forms of traditional Chinese exercises (TCEs) on the glycemic profile in people with type 2 diabetes. However, relatively little is kn... Background: There is increasing evidence showing the health benefits of various forms of traditional Chinese exercises (TCEs) on the glycemic profile in people with type 2 diabetes. However, relatively little is known about the combined clinical effectiveness of these traditional exercises. This study was designed to perform a systematic review and meta-analysis of the overall effect of 3 common TCEs (Tai Ji Quan, Qigong, Ba Duan Jin) on glycemie control in adults with type 2 diabetes. Methods: We conducted an extensive database search in Cochrane Library, EMBASE, PubMed, Web of Science, EBSCO, and China National Knowledge Infrastructure on randomized controlled trials published between April 1967 and September 2017 that compared any of the 3 TCEs with a control or comparison group on glycemic control. Data extraction was performed by 2 independent reviewers. Study quality was evaluated using the Coehrane Handbook for Systematic Reviews of Interventions, which assessed the risk of bias, including sequence generation, allocation concealment, blinding, completeness of outcome data, and selective outcome reporting. The resulting quality of the reviewed studies was characterized in 3 grades representing the level of bias: low, unclear, and high. All analyses were performed using random effects models and heterogeneity was quantified. We a priori specified changes in biomarkers of hemoglobin A1 c (in percentage) and fasting blood glucose (mmol/L) as the main outcomes and triglycerides, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein-cholesterol, 2-h plasma glucose, and fasting plasma glucose as secondary outcomes.Results: A total of 39 randomized, controlled trials (Tai Ji Quan = 11; Qigong= 6; Ba Duan Jin= 22) with 2917 type 2 diabetic patients (aged 41-80 years) were identified. Compared with a control or comparison group, pooled meta-analyses of TCEs showed a significant decrease in hemoglobin Alc (mean difference (MD)= -0.67%; 95% confidence interval (CI):-0.86% to-0.48%; p 〈 0.00001) and fasting blood glucose (MD = -0.66 mmol/L; 95%CI: -0.95 to -0.37 mmol/L; p 〈 0.0001). The observed effect was more pronounced for interventions that were medium range in duration (i.e., 〉3-〈 12 months). TCE interventions also showed improvements in the secondary outcome measures. A high risk of bias was observed in the areas of blinding (i.e., study participants and personnel, and outcome assessment). Conclusion: Among patients with type 2 diabetes, TCEs were associated with significantly lower hemoglobin Alc and fasting blood glucose. Further studies to better understand the dose and duration of exposure to TCEs are warranted.2018 Published by Elsevier B.V. on behalf of Shanghai University of Sport. This is an open access article under the CC BY-NC-ND license. (http://creativecommons.org/licenses/by-nc-nd/4.0/). 展开更多
关键词 Blood glucose HYPOGLYCEMIA Insulin sensitivity Physical activity
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Limb symmetry index in competitive alpine ski racers:Reference values and injury risk identification according to age-related performance levels 被引量:6
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作者 Lisa Steidl-Müller Carolin Hildebrandt +2 位作者 Erich Müiller Christian Fink Christian Raschner 《Journal of Sport and Health Science》 SCIE 2018年第4期405-415,共11页
Purpose: The aims of this study were to assess differences of limb symmetry index (LSI) in strength- and coordination-related tasks between high-level, competitive, noninjured ski racers of different age-related pe... Purpose: The aims of this study were to assess differences of limb symmetry index (LSI) in strength- and coordination-related tasks between high-level, competitive, noninjured ski racers of different age-related performance levels and to prospectively assess limb differences as a possible risk factor for traumatic and overuse injury in youth ski racers. Methods: The study (Study 1) included 285 high-level competitive ski racers (125 females, 160 males) of 3 age-related performance levels and based on the school system: 95 youth (10-14 years, secondary modem school), 107 adolescent (15-19 years, grammar school), and 83 elite athletes (20-34 years). To investigate the second aim (Study 2), 67 of the 95 youth athletes were included and any traumatic or overuse injuries were prospectively recorded over 2 seasons. All athletes performed 4 unilateral tests (strength related: one-leg counter movement jump (OL-CMJ) and one-leg isometric/isokinetic press strength test (OL-ILS); coordination related: one-leg stability test (OL-ST) and one-leg speedy jump test (OL-SJ)). The LSI was calculated by dividing the dominant leg by the nondominant leg and multiplying by 100. Kruskal-Wallis H tests and binary logistic regression analyses were conducted. Results: There were significant differences between the LSI of the 3 age-related performance-level groups only in the strength-related tests: the OL-CMJ (X^2(2, 285) = 9.09; p = 0.01) and the OL-ILS (X^2(2,285) = 14.79; p 〈 0.01). The LSI for OL-ILS was found to be a significant risk factor for traumatic injury in youth ski racers (Wald = 7.08; p 〈 0.01). No significant risk factors were found for overuse injuries. Conclusion: Younger athletes display slightly greater LSI values only in the strength-related tests. The cut-off value of limb differences of 〈 10% for return to sport decisions seems to be appropriate for elite athletes, but for youth and adolescent athletes it has to be critically discussed. It seems to be necessary to define thresholds based on specific performance tasks (strength vs. coordination related) rather than on generalizations, and age-related performance levels must be considered. Limb differences in unilateral leg extension strength represent a significant injury risk factor in youth ski racers.2018 Published by Elsevier B.V. on behalf of Shanghai University of Sport. This is an open access article under the CC BY-NC-ND license. (http://creativecommons.org/licenses/by-nc-nd/4.0/). 展开更多
关键词 Age-related performance levels Alpine ski racing Injury risk Limb differences Youth athletes
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Pacing and predictors of performance during cross-country skiing races:A systematic review 被引量:8
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作者 Thomas Stogg Barbara Pellegrini Hans-Christer Holmberg 《Journal of Sport and Health Science》 SCIE 2018年第4期381-393,共13页
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 t... 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 dance) skating across a race. Conclusion: We propose that skiers at all levels can improve their performance with more specific training in techniques (i.e., maintaining long cycles without compromising cycle rate and selecting appropriate techniques) in combination with training for endurance and more strength. Furthermore, we would advise less experienced skiers and/or those with lower levels of performance to apply a more even pacing strategy rather than a positive one (i.e., starting the race too fast).2018 Published by Elsevier B.V. on behalf of Shanghai University of Sport. This is an open access article under the CC BY-NC-ND license. (http://creativecommons.org/licenses/by-nc-nd/4.0/). 展开更多
关键词 Classic style Competition Cycle characteristics Positive pacing SKATING
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On the adjacent vertex-distinguishing acyclic edge coloring of some graphs 被引量:5
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作者 SHIU Wai Chee CHAN Wai Hong +1 位作者 ZHANG Zhong-fu BIAN Liang 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2011年第4期439-452,共14页
A proper edge coloring of a graph G is called adjacent vertex-distinguishing acyclic edge coloring if there is no 2-colored cycle in G and the coloring set of edges incident with u is not equal to the coloring set of ... A proper edge coloring of a graph G is called adjacent vertex-distinguishing acyclic edge coloring if there is no 2-colored cycle in G and the coloring set of edges incident with u is not equal to the coloring set of edges incident with v, where uv∈ E(G). The adjacent vertex distinguishing acyclic edge chromatic number of G, denoted by X'Aa(G), is the minimal number of colors in an adjacent vertex distinguishing acyclic edge coloring of G. If a graph G has an adjacent vertex distinguishing acyclic edge coloring, then G is called adjacent vertex distinguishing acyclic. In this paper, we obtain adjacent vertex-distinguishing acyclic edge coloring of some graphs and put forward some conjectures. 展开更多
关键词 Adjacent strong edge coloring adjacent vertex-distinguishing acyclic edge coloring.
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Sport participation and vigilance in children:Influence of different sport expertise 被引量:2
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作者 Rafael Ballester Florentino Huertas +1 位作者 Enrique Molina Daniel Sanabria 《Journal of Sport and Health Science》 SCIE 2018年第4期497-504,共8页
Purpose: The present study aimed to investigate the relationship between different types of sport expertise (externally-paced vs. self-paced sports) and vigilance performance in children by evaluating the cardiovas... Purpose: The present study aimed to investigate the relationship between different types of sport expertise (externally-paced vs. self-paced sports) and vigilance performance in children by evaluating the cardiovascular fitness level of the participants. Methods: Three groups of children (11.0 ± 0.2 years) differentiated in terms of their regular sport participation (football players, n = 20; track and field athletes, n = 20; non-athletic controls, n = 20) took part in the study. In one session, participants performed the Leger Multi-stage fitness test to estimate their aerobic fitness level. In another session, participants completed the Psychomotor Vigilance Task (PVT) to evaluate their vigilance performance under 2 conditions of velocity demands (normal vs. speed). Results: The results revealed that both groups of sport practitioners had higher cardiovascular fitness than non-athlete controls. In contrast, no significant differences in the performance PVT were found between track and field athletes and controls. Crucially, football players showed better performance in the PVT than track and field athletes and controls. These between-group differences were not modulated by the speed demands of the task. Conclusion: The major novel finding of this research points to a positive relationship between sport participation and vigilance performance during childhood. We discuss our results in terms of the different hypotheses put forward in the literature to explain the relationship between regular exercise and cognitive fimctioning: the "cardiovascular fitness" and the "cognitive component skills" hypotheses.2018 Published by Elsevier B.V. on behalf of Shanghai University of Sport. This is an open access article under the CC BY-NC-ND license. (http://creativecommons.org/licenses/by-nc-nd/4.0/). 展开更多
关键词 CHILDHOOD COGNITION Cognitive skills Physical activity Physical exercise Sustained attention
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Boundedness of Caldero'n-Zygmund operators in product Hardy spaces 被引量:2
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作者 HAN Yong-sheng YANG Da-chun 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2009年第3期321-335,共15页
By means of vector-valued product Calderón-Zygmund operators and some subtle estimates,the boundedness in product Hardy spaces on R^n × R^m of Calderón-Zygmund operators introduced by J.L. Journé i... By means of vector-valued product Calderón-Zygmund operators and some subtle estimates,the boundedness in product Hardy spaces on R^n × R^m of Calderón-Zygmund operators introduced by J.L. Journé is established. 展开更多
关键词 Hardy space product domain Calderón-Zygmund operator vector-valued operator
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Jichengite 3CuIr_2S_4·(Ni,Fe)_9S_8,a New Mineral,and Its Crystal Structure 被引量:2
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作者 Zuxiang Yü Ziguo HAO +2 位作者 Hanggen WANG Shuping YIN Jianhui CAI 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2011年第5期1022-1027,共6页
A new mineral,jichengite ideally 3CuIr_2S_4·(Ni,Fe)_9S_8,was found as a constituent of placer concentrates at a branch of the Luanhe River,about 220 km NNE of Beijing.Its associated minerals are chromite,magnetit... A new mineral,jichengite ideally 3CuIr_2S_4·(Ni,Fe)_9S_8,was found as a constituent of placer concentrates at a branch of the Luanhe River,about 220 km NNE of Beijing.Its associated minerals are chromite,magnetite,ilmenite,zircon,native gold,iridium,ferrian platinum and osmium.The placer is distributed at places around ultrabasic rock,which hosts chromite orebodies,from which PGM originated.Jichengite occurs commonly as massive or granular aggregates.No perfect morphology of jichengite was observed.It is steel gray and opaque with metallic luster and black streak.It has a Mohs hardness of 5,VHN(d) urn 21.65,H_m 4.465,Hv = 268.1 N/um^2.It is brittle and weakly magnetic. Cleavage {010} is rarely observed.No fracture was observed.Density could not be measured because of its too small grain size.Density(calc.) is 7.003 g/cm^3.Reflect light is reddish-brown,without internal reflections.Anisotropism is distinct with grayish or yellowish white in crossed nicols and bluish violetcopper red in uncrossed nicols.Jichengite shows weak pleochroism and strong bireflectance.The reflectance values in air at the Standard Commission on Ore Mineralogy wavelengths are:38.9,34.3 at 470 nm,38.9,34.5 at 546 nm,39.1,35.3 at 590 nm,39.2,36.8 at 650 nm,parallel-axial extinction.The six strongest lines in the X-ray powder-diffraction pattern[d in A,(I),(hkl)]are:3.00(100)(116),2.80(50) (205),2.48.(50)(208),1.916(40)(2,1,10),1.765(60)(220),1.753(50)(2,0,16).Five chemical analyses carried out,yielding the following results:S 25.76(25.49-5.97),Fe 10.03(9.78-10.31),Co 0.78 (0.75-0.81),Ni 12.48(12.32-12.85),Cu 4.77(4.69-4.83),Ir 46.98(46.14-47.89),sum 100.80wt%,which produced a formula(Cu_(1.556)Fe_(0.976))_(2.532)(Ir_(5.063)S_(10.126))·(Fe_(2.7451)Ni_(4.404)Co_(0.273))_(7.422)S_(6.517).The ideal formula is X_(10)Ir_5S_(17.5),which was calculated by single crystal structure analyses,where X=Cu(Ⅱ)+Fe(Ⅱ)+Ni(Ⅱ) +Co(Ⅱ).The single crystal data were collected using a diffractometer with Mo Kαradiation and a graphite monochromate.The crystal system is trigonal with space group R3m and unit cell parameters a=7.0745(14) A,c=34.267(10) A(The superstructure not found),and the final R Indices[with 564 observed reflections,I>2sigma(Ⅰ)]are R_1=0.0495,wR_2=0.1349.The specimens are deposited in the Geological Museum of China. 展开更多
关键词 jichengite crystal structure MINERAL
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A comparison of lower limb stiffness and mechanical muscle function in ACL-reconstructed,elite,and adolescent alpine ski racers/ski cross athletes 被引量:2
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作者 Matthew J.Jordan Per Aagaard Walter Herzog 《Journal of Sport and Health Science》 SCIE 2018年第4期416-424,共9页
Purpose: The aim of this study was to compare mechanical muscle function in the eccentric/concentric phases of vertical bilateral jumping in anterior cruciate ligament-reconstructed (ACLR), elite (ELITE), and ado... Purpose: The aim of this study was to compare mechanical muscle function in the eccentric/concentric phases of vertical bilateral jumping in anterior cruciate ligament-reconstructed (ACLR), elite (ELITE), and adolescent (ADOL) alpine ski racers and ski cross athletes. Methods: Alpine ski racers/ski crossers (ACLR: n = 12, age = 26.7 ± 3.8 years; ELITE: n = 12, age = 23.9 ± 3.0 years; ADOL: n = 12, age = 17.8 ± 0.7 years; females: n = 6 per group, males: n = 6 per group) performed 5 maximal countermovement jumps (CMJs) and 5 squat jumps. The ground reaction forces for each limb were analyzed using dual force plate recording to obtain body center of mass (BCM) velocity, displacement, and power. The eccentric deceleration (ECC) and concentric phases were determined from BCM velocity. CMJ net concentric and ECC impulses were calculated (body mass normalized) along with the peak and mean BCM power and maximal vertical jump height. CMJ lower limb stiffness (LLS) was determined by the slope of the ground reaction forces vs. the BCM displacement curve over the ECC phase. Concentric and ECC asymmetry indices were calculated for each leg, and the left vs. right LLS was compared. Outcome measures (reported as mean ± SD) calculated as a 5-jump mean were normalized to body mass and compared using an analysis of variance. Results: No between-group differences were found for peak and mean power or jump heights. There were no group differences for LLS or net concentric phase impulse, but the net ECC impulse was lower in the ADOL group compared with ELITE skiers (ADOL: 1.33 ± 0.32 Ns/kg; ELITE: 1.59 ± 0.16 Ns/kg; p 〈 0.05). Although no group differences were found for ECC asymmetry indices, a group × limb interaction was found for LLS (p 〈 0.01), which was systematically higher in the right vs. the left limb of ADOL skiers (right: 54.1 ± 17.9 N/m/kg; left: 48.7 ± 15.7 N/m/kg;p 〈 0.01). Conclusion: ADOL skiers demonstrated decreased ECC impulse and systematic right limb dominance in LLS compared with ACLR and ELITE skiers. The implication of these findings for injury and performance are unknown, but further investigation into these potential relationships is warranted.2018 Published by Elsevier B.V. on behalf of Shanghai University of Sport. This is an open access article under the CC BY-NC-ND license. (http://creativecommons.org/licenses/by-nc-nd/4.0/). 展开更多
关键词 Between-limb asymmetry Injury prevention Knee injuries Muscle power Vertical jump
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Single-layer graphene as a highly selective barrier for vanadium crossover with high proton selectivity 被引量:1
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作者 Saheed Bukola Zhaodong Li +5 位作者 Jason Zack Christopher Antunes Carol Korzeniewski Glenn Teeter Jeffrey Blackburn Bryan Pivovar 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第8期419-430,I0009,共13页
We report near-zero crossover for vanadium cross-permeation through single-layer graphene immobilized at the interface of two Nafion?polymer electrolyte membranes.Vanadium ion diffusion and migration,including proton ... We report near-zero crossover for vanadium cross-permeation through single-layer graphene immobilized at the interface of two Nafion?polymer electrolyte membranes.Vanadium ion diffusion and migration,including proton mobility through membrane composites,were studied with and without graphene under diffusion and migration conditions.Single-layer graphene was found to effectively inhibit vanadium ion diffusion and migration under specific conditions.The single-layer graphene composites also enabled remarkable ion transmission selectivity improvements over pure Nafion membranes,with proton transport being four orders of magnitude faster than vanadium ion transport.Resistivity values of 0.02±0.005Ωcm^(2) for proton and 223±4Ωcm^(2) for vanadium ion through single atomic layer graphene are reported.This high selectivity may have significant impact on flow battery applications or for other electrochemical devices where proton conductivity is required,and transport of other species is detrimental.Our results emphasize that crossover may be essentially completely eliminated in some cases,enabling for greatly improved operational viability. 展开更多
关键词 Ion selectivity Polymer electrolyte membrane Redox flow battery Single-layer graphene Vanadium crossover 2D nanomaterial
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Effects of Rhodiola rosea supplementation on mental performance,physical capacity,and oxidative stress biomarkers in healthy men 被引量:2
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作者 Ewa Jòwko Jerzy Sadowski +3 位作者 Barbara Dlugolecka Dariusz Gierczuk Benedykt Opaszowski Igor Cieslinski 《Journal of Sport and Health Science》 SCIE 2018年第4期473-480,共8页
Purpose: The objective of this study was to investigate the effects of chronic Rhodiola rosea (R. rosea) supplementation on mental and physical performance, as well as hormonal and oxidative stress biomarkers. Meth... Purpose: The objective of this study was to investigate the effects of chronic Rhodiola rosea (R. rosea) supplementation on mental and physical performance, as well as hormonal and oxidative stress biomarkers. Methods: Twenty-six healthy male students received either R. rosea extract (600 mg/day; RR) or placebo (PL) in a randomized double-blind trial. Prior to supplementation (Term I) and following 4 weeks of supplementation (Term II), the students underwent psychomotor tests for simple and choice reaction time, included in the Vienna Test System. Also, the subjects performed VO2peak test. Blood samples were obtained before and after the test to measure the hormonal profile (cortisol, testosterone, and growth hormone), as well as the biomarkers of oxidative stress (lipid hydroperoxides, total antioxidant capacity, and superoxide dismutase) and muscle damage (creatine kinase). Results: R. rosea ingestion shortened reaction time and total response time. Moreover, a greater relative increase in the number of correct responses was observed in RR group as compared to the PL group. No changes in endurance exercise capacity and hormonal profile were observed after R. rosea ingestion. R. rosea ingestion raised plasma total antioxidant capacity. It did not, however, affect other measured parameters. Conclusion: Chronic R. rosea ingestion does not affect physical performance, but can improve the results of some psychomotor tests (simple and choice reaction time) in young, healthy, and physically active men. The improvements in mental performance, however, at least in our study, seem not to be related to changes in cortisol release or antioxidant activity of R. rosea extract. Thus, the specific mechanisms responsible for these effects still need to be elucidated.2018 Published by Elsevier B.V. on behalf of Shanghai University of Sport. This is an open access article under the CC BY-NC-ND license. (http://creativecommons.org/licenses/by-nc-nd/4.0/). 展开更多
关键词 CORTISOL Endurance capacity Incremental exercise MEN Oxidative stress Simple and choice reaction time TESTOSTERONE
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Sedentary behavior and physical activity predicting depressive symptoms in adolescents beyond attributes of health-related physical fitness 被引量:1
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作者 gene l.farren tao zhang +1 位作者 xiangli gu katherine t.thomas 《Journal of Sport and Health Science》 SCIE 2018年第4期489-496,共8页
Background: Sedentary behavior (SB), physical activity (PA), and attributes of physical fitness have been shown to be related to depressive symptoms in adolescents. The purpose of the present study was to investi... Background: Sedentary behavior (SB), physical activity (PA), and attributes of physical fitness have been shown to be related to depressive symptoms in adolescents. The purpose of the present study was to investigate whether SB and fitness-producing activity predicted depression in active adolescents over and above gender and fitness attributes. Methods: Participants were 249 adolescents (age: 12.85 ± 0.89 years, mean ± SD) from 3 public middle schools who wore Actical accelerometers to assess their SB and PA. Participants also completed the FITNESSGRAM health-related fitness assessment and a brief depression questionnaire. A 3-step hierarchical regression analysis was conducted with gender and fitness attributes (i.e., body mass index (BMI), maximal volume oxygen uptake (VO2max), curlups, and pushups), moderate- and vigorous-intensity activity, and SB entered in respective steps. Results: Regression analysis indicated activity variables (i.e., moderate- and vigorous-intensity activity) significantly predicted depression (△R^2= 0.12, p 〈 0.01) beyond gender and fitness attributes. Overall, gender, fitness attributes, activity variables, SB explained 31% of the variance in depression. Structure coefficients revealed VO2max (rs= -0.77), moderate-intensity activity (rs= -0.67), vigorous-intensity activity (rs = -0.81), and SB (rs = 0.57) were substantially correlated with the criterion variable; thus, they were the strongest predictors of depression. Conclusion: The findings of the current study indicated SB and PA were both significant predictors of depression; however, sufficient fitness-producing activity and adequate cardiorespiratory fitness may nullify the negative influence of SB on depressive symptoms in active adolescents.2018 Published by Elsevier B.V. on behalf of Shanghai University of Sport. This is an open access article under the CC BY-NC-ND license. (http://creativecommons.org/licenses/by-nc-nd/4.0/). 展开更多
关键词 Accelerometers Adolescent health Cardiorespiratory fitness FITNESSGRAM Mental health Moderate-to-vigorous-intensity activity
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An FEM approximation for a fourth-order variational inequality of second kind 被引量:1
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作者 QIAN Fu-bin DING Rui 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第1期19-24,共6页
A fourth-order variational inequality of the second kind arising in a plate frictional bending problem is considered. By using regularization method, the original problem can be formulated as a differentiable variatio... A fourth-order variational inequality of the second kind arising in a plate frictional bending problem is considered. By using regularization method, the original problem can be formulated as a differentiable variational equation, and the corresponding discrete FEM variational equation is presented afterwards. Abstract error estimates and error estimates of the approximation are derived in terms of energy norm and L^2-norm. 展开更多
关键词 plate theory variational inequality of the second kind fourth-order problem FEM regularization error estimate.
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Soil fertility effect on water productivity of maize in the upper blue nile basin, Ethiopia 被引量:2
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作者 Teklu Erkossa Seleshi Bekele Awulachew Denekew Aster 《Agricultural Sciences》 2011年第3期238-247,共10页
Maize (Zea mays) is among the major cereals grown in the high rainfall areas of the subSaharan Africa’s (SSA) such as the Ethiopian part of the Blue Nile basin. However, its productivity is severely constrained by po... Maize (Zea mays) is among the major cereals grown in the high rainfall areas of the subSaharan Africa’s (SSA) such as the Ethiopian part of the Blue Nile basin. However, its productivity is severely constrained by poor soil, water and crop management practices. This study simulated the water productivity of the crop under varying soil fertility scenarios (poor, near optimal and none limiting) using hybrid seeds under rainfed conditions using the FAO AquaCrop model. The result indicated that grain yield of maize increased from 2.5 tons.ha–1 under poor to 6.4 and 9.2 tons.ha–1 with near optimal and non-limiting soil fertility conditions. Correspondingly, soil evaporation decreased from 446 mm to 285 and 204 mm, while transpiration increased from 146 to 268 and 355 mm. Consequently, grain water productivity was increased by 48% and 54%, respectively, with the near optimal and non-limiting soil fertility conditions. The water productivity gain mainly comes from reduced evaporation and increased transpiration without significantly affecting water left for downstream ecosystem services. This has a huge implication for a basin scale water management planning for various purposes. 展开更多
关键词 AquaCrop Simulation Water Productivity Soil FERTILITY Nitisols
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STRONG COMPARISON PRINCIPLES FOR SOME NONLINEAR DEGENERATE ELLIPTIC EQUATIONS 被引量:1
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作者 Yanyan LI Bo WANG 《Acta Mathematica Scientia》 SCIE CSCD 2018年第5期1583-1590,共8页
In this paper, we obtain the strong comparison principle and Hopf Lemma for locally Lipschitz viscosity solutions to a class of nonlinear degenerate elliptic operators of the form △2ψ + L(x,△ ψ), including the ... In this paper, we obtain the strong comparison principle and Hopf Lemma for locally Lipschitz viscosity solutions to a class of nonlinear degenerate elliptic operators of the form △2ψ + L(x,△ ψ), including the conformal hessian operator. 展开更多
关键词 Hopf lemma strong comparison principle degenerate ellipticity conformal invariance
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Electroencephalography Analysis Using Neural Network and Support Vector Machine during Sleep 被引量:3
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作者 JeeEun Lee Sun K. Yoo 《Engineering(科研)》 2013年第5期88-92,共5页
The purpose of this paper is to analyze sleep stages accurately using fast and simple classifiers based on the frequency domain of electroencephalography(EEG) signal. To compare and evaluate system performance, the ru... The purpose of this paper is to analyze sleep stages accurately using fast and simple classifiers based on the frequency domain of electroencephalography(EEG) signal. To compare and evaluate system performance, the rules of Rechtschaffen and Kales(R&K rule) were used. Parameters were extracted from preprocessing process of EEG signal as feature vectors of each sleep stage analysis system through representatives of back propagation algorithm and support vector machine (SVM). As a result, SVM showed better performance as pattern recognition system for classification of sleep stages. It was found that easier analysis of sleep stage was possible using such simple system. Since accurate estimation of sleep state is possible through combination of algorithms, we could see the potential for the classifier to be used for sleep analysis system. 展开更多
关键词 SLEEP ELECTROENCEPHALOGRAPHY NEURAL Network Backpropagation Algorithm SVM
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