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921.
922.
Giles LV Warburton DE Esch BT Fedoruk MN Rupert JL Taunton JE 《Journal of sports sciences》2012,30(3):261-267
The purpose of this study was to determine the effects of short-term normoxic and hypoxic exercise on plasma endothelin-1 and nitric oxide levels, and the relationship of arterial compliance and pulmonary artery pressure to endothelin-1. Seven endurance-trained males completed two incremental and two steady-state exercise tests performed at ventilatory threshold in normoxia and hypoxia (fraction of inspired oxygen = 0.14). Plasma endothelin-1was measured throughout steady-state tests. Arterial compliance using applanation tonometry, plasma nitric oxide and pulmonary artery pressure using Doppler echocardiography were measured before and after exercise. Small arterial compliance and pulmonary artery pressure significantly increased following exercise. There were no main effects of condition or time for plasma endothelin-1and nitric oxide levels. There were no significant relationships between plasma endothelin-1 and arterial compliance or pulmonary artery pressure. In conclusion, mechanisms other than the endothelial system may play a role in the exercise-induced changes in small artery compliance in this study population. Moderate hypoxia and a 30-minute steady-state exercise have limited effects on plasma endothelin-1 in endurance-trained males. 相似文献
923.
LIU Dong WANG Fei HUANG Qun-xing YAN Jian-hua CHI Yong CEN Ke-fa 《浙江大学学报(A卷英文版)》2007,8(11):1853-1857
Radiative imaging of combustion flame in furnace of power plant plays an increasingly important role in combustion diagnosis. This paper presents a new method for calculating the radiative imaging of three-dimensional (3D) combustion flame based on Monte Carlo method and optical lens imaging. Numerical simulation case was used in this study. Radiative images were calculated and images obtained can not only present the energy distribution on the charge-coupled device (CCD) camera target plane but also reflect the energy distribution condition in the simulation furnace. Finally the relationships between volume ele- ments and energy shares were also discussed. 相似文献
924.
Bülent 《浙江大学学报(A卷英文版)》2010,11(2):106-114
In this study, an electro-mechanical valve (EMV) system for the intake valve ofa fottr stroke, single cylinder, overhead valve and spark ignition (SI) engine was designed and constructed. An engine with the EMV system and a standard engine were tested to observe the effects of the EMV on engine performance and emissions at different speeds under full load. The EMV engine showed improved engine power, engine torque and break specific fuel consumption (BSFC). A 66% decrease in CO emissions was also obtained with the EMV system, but hydrocarbons (HC) and NOx emissions increased by 12% and 13% respectively. 相似文献
925.
In the comprehension of multiple controversial scientific texts, readers with strong prior beliefs tend to construct a one-sided mental representation that is biased towards belief-consistent information. In the present study, we examined whether an argument in contrast to a summary task instruction can increase the resource allocation to and strategic validation of belief-inconsistent information which should be positively related to comprehension. Undergraduate students read one belief-consistent and one belief-inconsistent text about a controversial scientific issue either with an argument or a summary task instruction. The use of strategic validation and memorization strategies was assessed with think-aloud protocols, and a verification task was used to investigate comprehension outcomes. As predicted, readers following a summary task read belief-consistent information longer and used more memorization strategies for such information. Readers following an argument task spent similar time reading both text types and used more validation strategies when reading the belief-inconsistent text. In addition, the use of strategic validation during reading the belief-inconsistent text improved comprehension for this text type but hindered the comprehension of the belief-consistent text. 相似文献
926.
Nicholas Popper 《Archival Science》2010,10(3):249-266
This article investigates the long-term transformations in England’s documentary storage regime wrought by the Reformation.
Henry VIII’s Dissolution of the Monasteries famously resulted in the dispersal and destruction of many medieval texts and
records, but he and his successors sponsored efforts to retrieve lost materials, which they then used in the formation of
ecclesiastical policy. Elizabethan counselors expanded the scope of this project, applying their expertise in gathering records
to secular issues and assiduously preserving their own documents. During James I’s reign, the Earl of Salisbury’s patronage
gave new authority to the State Paper Office, encouraging the consolidation of a centralizing archive that integrated earlier
methods of collection, preservation, and indexing in its operation and construction. The article thus offers an analytic trajectory
tying the practices of Reformation to the development of expanding national archives in the seventeenth century. 相似文献
927.
Jung Cheol Shin 《Higher Education》2009,58(5):669-688
This study evaluated the effects of South Korea’s Brain Korea 21 (BK 21) project, a special research funding program designed
to build world-class research university. The effects were measured by examining the frequency of article publications in
SCI journals during the 1995–2005 period. The results of the analysis indicated that the growth of research publications from
Korean research universities was increased significantly following the implementation of the BK 21 project in 1999. In addition,
during the period under study, four research universities (Yonsei, Korea, Sungkyunkwan, and Hanyang) were newly emerged. However,
the growth rate of research publications was not different from that of the US and Japan, and even less than that of China.
Thus, although the BK 21 project contributed to the growth of research publications of Korean universities, the project did
not lessen the gap between Korea universities and world-class research universities in the US or Japan in number of publications. 相似文献
928.
The main purpose of this study was to explore the factors mediating the translation of second grade teachers’ nature of science (NOS) views into classroom practice after completing a graduate level NOS course. Four second grade in-service elementary teachers comprised the sample of this study. Data were collected from several sources during the course of this study. The primary data sources were (a) assessment of the elementary teachers’ NOS views before and after the graduate level NOS course using the Views of Nature of Science Questionnaire Version B (VNOS-B) (Lederman et al., 2002) coupled with interviews, and (b) a classroom observation and videotaped recording of the elementary teachers’ best NOS lessons coupled with interview. We identified three distinct but related factors that mediated the translation of NOS views into classroom practice: the teachers’ perspectives about the developmental appropriateness of the NOS aspect, the teachers’ selection of target NOS aspects, and the relative importance placed by teachers on each NOS aspect. 相似文献
929.
930.
J. Bruce Francis Michalina Vaughan Colin Flood Page Sally Tomlinson R. A. Becher Margaret C. Ives John Urry K. G. Collier Meir Zadok Charles Carter Jürgen Schramm Jean Barry Graeme C. Moodie Donald Bligh R. A. King D. G. Mulcahy Peter Scott F. R. Charmer T. R. Bone John A. Hughes Roger Greenhough Alec M. Ross John Wakeford Joyce Skinner Duncan B. Nimmo Cedric Cullingford L. R. B. Elton 《Higher Education》1979,8(6):709-744