期刊文献+
共找到5篇文章
< 1 >
每页显示 20 50 100
Solar term peak of onset and death in 1 597 patients with acute ischemic stroke Circular statistical analysis 被引量:1
1
作者 Mingfeng He Zhangrong Liang +7 位作者 Jiping Zhang Zhenhe Gao Shaoyong Mo Yingjian Zhang Fang Shen Zixing Chen Liyun Cai Weihong Xiang 《Neural Regeneration Research》 SCIE CAS CSCD 2007年第9期532-535,共4页
BACKGROUND: Previously, time data were analyzed by using constituent ratio or relative ratio; however, circular statistical analysis could exactly provide average peak phase of diseases. OBJECTIVE: To investigate th... BACKGROUND: Previously, time data were analyzed by using constituent ratio or relative ratio; however, circular statistical analysis could exactly provide average peak phase of diseases. OBJECTIVE: To investigate the correlation of solar term peak with onset and death of acute ischemic stroke. DESIGN: Retrospective case analysis. SETTINGS: Emergency Department of Foshan Municipal Hospital of Traditional Chinese Medicine; Department of Science and Education, the Second People's Hospital of Foshan. PARTICIPANTS: A total of 1 597 patients with acute ischemic stroke were selected from Emergency Room, Department of Neurology, Foshan Municipal Hospital of Traditional Chinese Medicine from 1994 to 2002. There were 875 males and 722 females, and their ages ranged from 33 to 97 years. All cases met the diagnostic criteria of acute cerebral infarction modified by the Second National Cerebrovascular Disease Academic Meeting; meanwhile, they were diagnosed with CT/MRI test. Patients and their relatives provided the confirmed consent. METHODS: Solar term of onset was retrospectively analyzed in 1 597 patients with acute ischemic stroke; among them, solar term of death in 90 cases were analyzed by using circular statistical analysis to calculate peak phase of onset and death of acute ischemic stroke and investigate the correlation of solar term with onset and death of acute ischemic stroke. MAIN OUTCOME MEASURES: Onset and death time of patients with acute ischemic stroke. RESULTS: Solar term of onset in 1 597 patients, especially solar term of death in 90 patients, was not concentrated (P 〉 0.05), and specific peak phase was not found out. Acute ischemic stroke low attacked from vernal equinox to summer begins, but death caused by acute ischemic stroke high attacked from grain buds to autumn begins. CONCLUSION: Patients with acute ischemic stroke do not have specific solar term peak of onset and death. 展开更多
关键词 cerebral infarct INCIDENCE DEATH circular statistical analysis
下载PDF
Do vegetative and reproductive phenophases of deciduous tropical species respond similarly to rainfall pulses? 被引量:3
2
作者 A.P.Silveira F.S.Araújo F.R.Martins 《Journal of Forestry Research》 SCIE CAS CSCD 2013年第4期643-651,共9页
Deciduous trees with high-density wood that occur in dry seasonal tropical regions respond to rainfall seasonality with synchrony in phenophases. However, they may exhibit interannual differences in synchrony and inte... Deciduous trees with high-density wood that occur in dry seasonal tropical regions respond to rainfall seasonality with synchrony in phenophases. However, they may exhibit interannual differences in synchrony and intensity of phenophases, as strategy for large variations in duration and intensity of rainfall pulses. Nevertheless, it remains unknown how phenophases of deciduous trees of the Brazilian semi-arid region respond to rainfall variations. The phenology of Cordia oncocalyx was monitored in deciduous thorny woodland (Caatinga), from April 2009 to March 2011, and was correlated with rainfall, soil humidity, temperature, and photoperiod. The rainy years 2009 and 2011 exhibited higher duration of rainfall pulses and lower frequency of interpulses, but in 2010 pulse duration and total rainfall were lower. Circular statistics showed leaf flush followed by flowering and fruiting in the rainy season, and leaf fall and seed dispersal in the dry season. 展开更多
关键词 ASYNCHRONY circular analysis DECIDUOUS PHENOLOGY riskspreading seasonality.
下载PDF
THE CALCULATION OF IN-LINE FORCE ON A VERTICAL CIRCULAR CYLINDER AND ANALYSIS OF HYDRODYNAMIC COEFFICIENTS C_D AND C_M IN WAVE-CURRENT CO-EXISTING FIELD 被引量:1
3
作者 Kang Hai-gui Li Yu-cheng Wang Hong-rong, Dalian University of Technology, Dalian 116024, P.R.China 《Journal of Hydrodynamics》 SCIE EI CSCD 1991年第2期29-41,共13页
The purpose of this paper is to find some better methods for calculating in-line forces on a vertical circular cylinder and for analysing the hydrodynamic coefficients C_D and C_M in wave-current co-existing field. In... The purpose of this paper is to find some better methods for calculating in-line forces on a vertical circular cylinder and for analysing the hydrodynamic coefficients C_D and C_M in wave-current co-existing field. In this pa- per, in order to calculate hydrodynamic forces, the authors try to find a way of applying a great number of the re- sults about C_D and C_M for wave-only field in the case of wave-current co-existing field, and the results about C_D and C_M obtained in regular waves in the ease of irregular waves. Such a way may be of significance in engineering and further research. 展开更多
关键词 THE CALCULATION OF IN-LINE FORCE ON A VERTICAL circular CYLINDER AND analysis OF HYDRODYNAMIC COEFFICIENTS C_D AND C_M IN WAVE-CURRENT CO-EXISTING FIELD LINE CO
原文传递
Circular Bragg lasers with radial PT symmetry:Design and analysis with a coupled-mode approach
4
作者 ZIYAO FENG JINGWEN MA +1 位作者 ZEJIE YU XIANKAI SUN 《Photonics Research》 SCIE EI 2018年第5期I0019-I0023,共5页
Parity–time(PT) symmetry has been demonstrated in the frame of classic optics. Its applications in laser science have resulted in unconventional control and manipulation of resonant modes. PT-symmetric periodic circu... Parity–time(PT) symmetry has been demonstrated in the frame of classic optics. Its applications in laser science have resulted in unconventional control and manipulation of resonant modes. PT-symmetric periodic circular Bragg lasers were previously proposed. Analyses with a transfer-matrix method have shown their superior properties of reduced threshold and enhanced modal discrimination between the radial modes. However, the properties of the azimuthal modes were not analyzed, which restricts further development of circular Bragg lasers. Here, we adopt the coupled-mode theory to design and analyze chirped circular Bragg lasers with radial PT symmetry. The new structures possess more versatile modal control with further enhanced modal discrimination between the azimuthal modes. We also analyze azimuthally modulated circular Bragg lasers with radial PT symmetry, which are shown to achieve even higher modal discrimination. 展开更多
关键词 circular Bragg lasers with radial PT symmetry:Design and analysis with a coupled-mode approach PT
原文传递
Tree phenology along a successional gradient of tropical Atlantic Forest
5
作者 Fernanda C.G.Cardoso Victor P.Zwiener Marcia C.M.Marques 《Journal of Plant Ecology》 SCIE CSCD 2019年第2期272-280,共9页
Aims Changes in habitat characteristics and species composition in suc-cessional gradients could determine temporal variation in phenol-ogy of second-growth forests.We evaluated phenological patterns in tree species o... Aims Changes in habitat characteristics and species composition in suc-cessional gradients could determine temporal variation in phenol-ogy of second-growth forests.We evaluated phenological patterns in tree species occurring in successional forests in southern Brazil,aiming to assess community changes along succession.We tested for general patterns and phenophase seasonality of trees of forests in successional stages and for differences in occurrence,concentra-tion,frequency and duration of phenophases.Methods Vegetative(flushing and leaf-fall)and reproductive(flowering and fruiting)phenophases of 149 individuals of 29 tree species were monitored monthly,for 2 years,in a successional gradient:early-(~10 years),mid-(~30 years)and late-successional(>80 years)forests in southern Brazil.Important Findings Forests in the successional gradient exhibited shared frequency and duration of phenological phases,probably due to climatic or historical constraints in phenology.However,we found differences in the rate of occurrence and concentration of phenological phases,suggesting that habitat changes caused by succession and species turnover are additional factors affecting phenological patterns in tropical forests. 展开更多
关键词 Brazil circular analysis phenological patterns SUCCESSION
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部