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This paper uses the panel data of energy consumption (EC) and economic growth (GDP) for 51 countries from 1971 to 2005. These countries are divided into three groups: low income group, lower middle income group and upper middle income group countries. Firstly, a relationship between energy consumption and economic growth is investigated by employing Pedroni (1999) panel cointegration method. Secondly, panel causality test is applied to investigate the way of causality between the energy consumption and economic growth. Finally, we test whether there is a strong or weak relationship between these variables by using Pedroni (2001) method. The empirical results of this study are as follows: i) Energy consumption and GDP are cointegrated for all three income group countries. ii) The panel causality test results reveal that there is long-run Granger causality running from GDP to EC for low income countries and there is bidirectional causality between EC and GDP for middle income countries. iii) The estimated cointegration factor, β, is not close to 1. In other words, no strong relation is found between energy consumption and economic growth for all income groups considered in this study. The findings of this study have important policy implications and it shows that this issue still deserves further attention in future research.  相似文献   
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Three novel one-dimensional (1D) coordination polymers with general formula {[M(μ-sq)2(amp)2]·H2O}n [M=Cu(II) (1), Zn(II) (2)] and [Cd(μ-sq)2(amp)2]n (3) [sq: Squarate; amp:2-aminomethylpyridine] have been prepared and spectroscopically studied. Each metal (II) ion in 13 is octahedrally coordinated by two sq and two amp ligands. The amp ligands are N,N′ coordinated, while the sq ligands bridge the metal centers forming 1D linear chain structure. The individual chains are linked by O–H···O hydrogen bonds involving the hydrogens of water molecules (12), amino hydrogens and squarate O atoms (13). The hydrogen bonded layers are further assembled into three-dimensional supramolecular networks by weak aromatic π–π interactions. EPR results indicate that the ground state of the paramagnetic electron in 1 and Cu2+ doped complexes 23 is dx2 - y2 d_{{x^{2} - y^{2} }} . Magnetic measurements reveal that complex 1 shows paramagnetic behavior.  相似文献   
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Haematuria and proteinuria are important symptoms of primary and secondary nephropathies. We report three african children presenting to our center in whom infection with S. haematobium resulted in haematuria and proteinuria. The third patient concomitantly suffered from steroid-sensitive relapsing nephrotic syndrome with the histological features of focal and segmental glomerulo-sclerosis. The diagnosis was in all cases established by light microscopy and urinary symptoms improved after treatment with praziquantel. In the third patients long term remission of the nephrotic syndrome could be maintained after 4 doses of praziquantel for recurrent bladder symptoms. We conclude that bilharziosis must be considered in the differential diagnosis of children with haeamturia and proteinuria even in Europe. The diagnosis can be established easily by light microscopy and an effective and low-risk treatment (with Praziquantel) can be offered.  相似文献   
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Sixteen percent of hospital room surfaces remained colonized by vancomycin-resistant enterococci (VRE) after routine terminal disinfection. Disinfection with a new "bucket method" resulted in uniformly negative cultures. Conventional cleaning took an average of 2.8 disinfections to eradicate VRE from a hospital room, while only one cleaning was required with the bucket method.  相似文献   
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The hydration of calcium silicates occurs by a series of complex, interrelated processes. A study conducted to determine the role of calcium silicate grain lattice defects in these processes found two processes at work during early hydration (0 to 5 minutes): (i) adsorption on the grain, followed by (ii) a chemical reaction to form the first C-S-H hydrate. The lattice defects in the grain have a direct relationship to the length of the induction period, and the number of defects, or degree of crystal disorder, directly influences the amount of enhanced reactivity.  相似文献   
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Total fatty acid compositions and its seasonal variations in Vimba, Vimba vimba tenella (Nordmann, 1840) in E?irdir Lake, which is the second largest freshwater lake in Turkey, were investigated by a gas chromatographic method. Twenty seven different fatty acids were determined in the composition of Vimba vimba tenella. Monounsaturated fatty acids (MUFAs) were found to be in higher amounts than saturated fatty acids (SFAs) and polyunsaturated fatty acids (PUFAs) in all seasons. Oleic acid (C18:1 n9) was the major MUFA in all seasons. Palmitic acid (C16:0) was identified as the major SFA in all four seasons. Arachidonic acid (C20:4 n6), docosahexaenoic acid (C22:6 n3), linoleic acid (C18:2 n6), and eicosapentaenoic acid (C20:5 n3) were at the highest levels among the PUFAs. In the present study, n-3/n-6 ratios were found to be 1.4,1.5,1.2 and 1.4 in spring, summer, autumn and winter, respectively. Vimba vimba tenella may be a valuable food for human consumption in terms of fatty acids.  相似文献   
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