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This paper investigates the causal relationships between per capita CO2 emissions, gross domestic product (GDP), renewable and non-renewable energy consumption, and international trade for a panel of 25 OECD countries over the period 1980–2010. Short-run Granger causality tests show the existence of bidirectional causality between: renewable energy consumption and imports, renewable and non-renewable energy consumption, non-renewable energy and trade (exports or imports); and unidirectional causality running from: exports to renewable energy, trade to CO2 emissions, output to renewable energy. There are also long-run bidirectional causalities between all our considered variables. Our long-run fully modified ordinary least squares (FMOLS) and dynamic ordinary least squares (DOLS) estimates show that the inverted U-shaped environmental Kuznets curve (EKC) hypothesis is verified for this sample of OECD countries. They also show that increasing non-renewable energy increases CO2 emissions. Interestingly, increasing trade or renewable energy reduces CO2 emissions. According to these results, more trade and more use of renewable energy are efficient strategies to combat global warming in these countries. 相似文献
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M. Masuyama 《Biometrical journal. Biometrische Zeitschrift》1991,33(6):725-733
A mathematical model of the linearized growth curve and its physiological interpretation by the introduction of proper age, which is proportional to the chronological age, are presented here. In the second phase, but not in the first phase, this constant of proportionality is highly correlated with the age at menarche. 相似文献
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Cynthia Nafula Wakhungu Isaiah Masinde Tabu O. Daniel Otaye Wafula Victor Wasike 《Archives Of Phytopathology And Plant Protection》2017,50(7-8):398-414
A study was carried out to determine Fusarium wilt distribution in Bambara nut farmers’ fields and its management using farm yard manure (FYM). Four villages in Busia County were purposively sampled for the study. The data generated were subjected to analysis of variance and treatment means separated by least significant difference test. Fusarium wilt incidence in the fields ranged from 14.63 to 43.56%. In the greenhouse, FYM reduced the disease incidence by 10.2% and severity by 9.5% on the black landrace and 1.9 and 12.8%, respectively, on the red landrace. In the field, FYM reduced disease incidence by 9.1% and severity by 6.9% on the black landrace and 10.4 and 10.4%, respectively, on the red landrace. Farm yard manure had the lowest area under disease progress curve irrespective of the landrace. The study confirmed the presence of the pathogen in the fields and the ability to manage the disease using FYM. 相似文献
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A photosensitive chemical oscillating reaction, i.e., the Briggs-Rauscher (B.R.) reaction, exhibiting a wealth of nonlinear behavior, when performed in a continuous-flow stirred-tank reactor, and subjected to periodic light irradiation, is studied as an experimental example of entrainment phenomena observable in biological systems. The adaptation patterns under periodic light irradiation are elucidated by means of the response of the system to continuous and single-pulse light irradiation. It is shown that self-oscillating states, excitable steady states and bistable systems can exhibit the same types of synchronization patterns when submitted to periodic external forces with appropriate amplitude and time scale conditions. 相似文献
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C. M. Girard 《Plant Ecology》1982,48(3):219-226
Two radiometers measuring reflectance factors have been used at a height of 1.50 m above some grasslands in C. France. The results show that both spectral data are sensitive to the photosynthetic activity of the grassland. Measurements made in April, May, June and July show that grasslands have quite different spectral behaviour according to soil conditions or to grazing level. Grasslands on dry or wet soils may be separated from those of normal soils for which overgrazing and trampling affecting the growth of species, are shown by the different spectral values. Such on the ground remote sensing measurements may then be proposed for evaluating the range of growth and development of different grasslands.Convention C.N.E.S./I.N.A.P-G. ref.: 80/CNES/24 I thank CNES and IGN for the facilities given to assume this experiment. Many thanks to Lynn Erselius, who revised the text. Mr. Lecordix, a student from the Ecole Nationale des Sciences Géographiques and Mr. Besnard, a student from the Orsay University (Plant Biology) helped in the collection and handling of spectral resp, floristical data. 相似文献
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Abstract The proteolytic activity of several black-pigmented Bacteroides species was measured. Bacteroides gingivalis was the only species having collagenolytic activity. General proteolytic activity on gelatin and Azocoll was shown in cultures of B. gingivalis, B. asaccharolyticus, B. endodontalis, B. intermedius, B. corporis and to a lesser extent B. melaninogenicus; B. loescheii did not show proteolytic activity. When culture filtrates were tested, B. gingivalis showed high cell free proteolytic activity, whereas the other species had only very weak cell free activity. Growth curves of B. gingivalis revealed two distinct proteolytic activities; general proteolytic activity was found during the logarithmic growth phase, whereas a second peak containing high collagenolytic activity was found after prolonged incubation of cells showing autolysis. 相似文献
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