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Mortality in relation to changes in physical activity in middle-aged to older Chinese:An 8-year follow-up of the Guangzhou Biobank Cohort Study 被引量:2
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作者 Yingyue Huang Chaoqiang Jiang +5 位作者 Lin Xu Weisen Zhang Feng Zhu Yali Jin Kar Keung Cheng Tai Hing Lam 《Journal of Sport and Health Science》 SCIE 2021年第4期430-438,共9页
Background:Physical activity(PA)is generally encouraged.Studies from developed countries in the West have shown that maintenance of adequate PA or increasing PA are associated with lower mortality risk.It is unclear w... Background:Physical activity(PA)is generally encouraged.Studies from developed countries in the West have shown that maintenance of adequate PA or increasing PA are associated with lower mortality risk.It is unclear whether these associations apply to an older Chinese population.Hence,we examined the changes in PA prospectively among a middle-aged and older Chinese population over an average of 4 years and explored their subsequent mortality risks.Methods:Metabolic equivalent scores of PA among participants in the Guangzhou Biobank Cohort Study were calculated.Participants were divided into 3 groups related to PA level,and changes in PA were classified into 9 categories.Information on vital status and causes of death from March 2008 to December 2012(the first repeated examination)until December 31,2017,was obtained via record linkage with the Death Registry.Results:Of 18,104 participants aged 61.21±6.85 years(mean±SD),1461 deaths occurred within 141,417 person-years.Compared to participants who maintained moderate PA,those who decreased PA from moderate or high levels to a low level had increased risks for all-cause mortality(hazard ratio(HR)=1.47,95%confidence interval(95%CI):1.11-1.96).Participants who maintained a high level of PA(HR=0.83,95%CI:0.70-0.98)or increased PA from low to high levels(HR=0.71,95%CI:0.52-0.97)showed lower all-cause mortality risks.Those who maintained low PA levels showed a higher all-cause mortality risk,whereas those who increased their PA levels showed a non-significantly lower risk.Similar results were found for cardiovascular disease risk.Conclusion:Even at an older age,maintaining a high PA level or increasing PA from low to high levels results in lower mortality risks,suggesting that substantial health benefits might be achieved by maintaining or increasing engagement in adequate levels of PA.The increased risk of maintaining a low PA level or decreasing PA to a low level warrants the attention of public health officials and clinicians. 展开更多
关键词 All-cause mortality Cardiovascular disease mortality change in physical activity
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Research on the Antarctic Atmosphere andUpper-Atmospheric Physical Processes andTheir Response to Global Change
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《中国气象科学研究院年报》 1999年第0期25-25,共1页
关键词 Research on the Antarctic Atmosphere andUpper-Atmospheric physical Processes andTheir Response to Global change
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Worrying about Climate Change
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作者 Naser W. Alnaser Roger Flanagan +3 位作者 Lawrence Kazmerski Ali A. Sayigh Munir H. Nayfeh Waheeb E. Alnaser 《Atmospheric and Climate Sciences》 2022年第2期441-461,共21页
It is becoming clear that Climate Change is getting severe. It was reported that the improved ocean heat measurements have a rate of warming upwards from 4 to 5 Hiroshima bombs liberated heat per second or 388,800 per... It is becoming clear that Climate Change is getting severe. It was reported that the improved ocean heat measurements have a rate of warming upwards from 4 to 5 Hiroshima bombs liberated heat per second or 388,800 per day. It was reported also that our climate has accumulated the equivalent of a total of more than 2.8 billion Hiroshima bombs’ worth of heat since 1998. Despite this global concern about the effect of global change on environment, it is believed that the problem is much more severe and with greater impact on all facets of life. The effect of Climate Change, especially with a 1&#8451;increase in global temperature (from 14&#8451;to 15&#8451;) is equivalent to the heat liberated from explosion of about 300 million Hiroshima of atomic bomb. This is why this CoP 26 becomes more serious and had targeted year 2060 as a year of zero CO<sub>2</sub> emission. This paper discusses the impact of climate change on ten sectors;water, water desalination, energy, renewable energy supply, health, society, agriculture, economy, industry, and built environment. 展开更多
关键词 Global Warming Impact of Climate change Major Impact of Climate change Physics of Climate change
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The effect of physical property change on the water flooding development in Changqing oilfield Jurassic low permeability reservoir 被引量:1
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作者 Yangnan Shangguan Yongqiang Zhang Weiliang Xiong 《Petroleum》 2015年第4期300-306,共7页
Changqing old oilfield Jurassic reservoir's average calibration recovery is 24.7%,with geological reserves recovery of 16.6%,water cut of 65.2%.And most of Jurassic reservoirs are in the middle and later field lif... Changqing old oilfield Jurassic reservoir's average calibration recovery is 24.7%,with geological reserves recovery of 16.6%,water cut of 65.2%.And most of Jurassic reservoirs are in the middle and later field life,part of them has entered the high water cut and high recovery stage.Traditional water flooding way for improving oil recovery becomes more difficult,and new method has to be considered.Maling oilfield BS district is a typical representative,with high water cut of 90.8%,high recovery percent of 26.1%and low oil recovery rate of 0.25%.To explore the new way to improve oil recovery,the polymer and surfactant(SP for short)important pilot test has been developed.The low permeability reservoir indoor core data in high water cut stage and inspection well results indicate that the reservoir permeability,pore combination characteristics and pore type changed greatly after long-term water flooding development.These changes bring more difficulties to the continue development,especially the high injection pressure,which can cause other problems for well pattern infilling and EOR.This paper takes the high injection pressure problem of Maling BS district Jurassic reservoir for example,analyzes the physical property change law on the following aspects:the development mode in the past,core analysis,formation sensitivity,interstitial matter,well test interpretation results,in order to help to further effective development and provide important parameters for tertiary oil recovery technique for similar reservoirs and others. 展开更多
关键词 Jurassic reservoir physical property change Water flooding Core analysis EOR Low permeability
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Structural evolution of carbon aerogel microspheres by thermal treatment for high–power supercapacitors
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作者 Feng Li Lijing Xie +5 位作者 Guohua Sun Fangyuan Su Qingqiang Kong Yufang Cao Xiangyun Guo Chengmeng Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2018年第2期439-446,共8页
In this work, a series of carbon aerogel microspheres(CAMs) with tailored pore structures were successfully prepared via a sol-gel method and subsequent heat-treatment at various temperatures from 600 to 1600 ℃. Th... In this work, a series of carbon aerogel microspheres(CAMs) with tailored pore structures were successfully prepared via a sol-gel method and subsequent heat-treatment at various temperatures from 600 to 1600 ℃. The effects of heat-treatment temperature(HTT) on the CAM microstructure were systematically investigated by physical and chemical characterization. The electrical conductivity increased by up to 250 S/cm and mesopores with high electrolyte accessibility developed in the CAM with increasing HTT. However, the specific surface area(SSA) decreased for HTTs from 1000 to 1600 ℃. The results show that these two factors should be finely balanced for further applications in high power supercapacitors.The CAMs carbonized at 1000 ℃ had the highest SSA(1454 m^2/g), large mesoporous content(20%) and favorable conductivity(71 S/cm). They delivered a high energy density of 38.4 Wh/kg at a power density of 0.17 kW/kg. They retained an energy density of 25.5 Wh/kg even at a high power density of 10.2 kW/kg,and a good rate capability of 84% after 10,000 cycles. This performance is superior to, or at least comparable to, those of most reported carbon materials. 展开更多
关键词 Carbon aerogel microspheres Heat-treatment temperature physical/chemical changes CONDUCTIVITY SUPERCAPACITOR
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Concrete Physics Method for Solving NP hard Problem
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作者 Huang Wen\|qi College of Computer Science, Huazhong University of Science and Technology, Wuhan 430074,China Laboratory of Computer Science, Institute of Software, Chinese Academy of Sciences, Beijing 100080, China 《Wuhan University Journal of Natural Sciences》 CAS 2001年第Z1期140-146,共7页
With a NP hard problem given, we may find a equivalent physical world. The rule of the changing of the physical states is simply the algorithm for solving the original NP hard problem .It is the most natural algorithm... With a NP hard problem given, we may find a equivalent physical world. The rule of the changing of the physical states is simply the algorithm for solving the original NP hard problem .It is the most natural algorithm for solving NP hard problems. In this paper we deal with a famous example , the well known NP hard problem——Circles Packing. It shows that our algorithm is dramatically very efficient. We are inspired that, the concrete physics algorithm will always be very efficient for NP hard problem. 展开更多
关键词 concrete physics algorithm NP hard problem circles packing the rule of the changing of the physical states
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