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21.
This study explores the relationship between electricity consumption, real gross domestic product per capita and carbon dioxide emissions in Zimbabwe. To achieve this, the study set off by examining the stationarity properties of the variables under review with the Zivot-Andrews (1992 Zivot, E., and D.W.K. Andrews. 1992. Further evidence on the great crash, the oil-price shock, and the unit-root hypothesis. Journal Of Business and Economic Statistics 10:251-270. doi: http://dx.doi.org/10.2307/1391541.[Taylor &; Francis Online], [Web of Science ®] [Google Scholar]) unit root test that accounts for a single structural break. Subsequently, Maki (2012 Maki, Daiki. 2012. “Tests for Cointegration Allowing for an Unknown Number of Breaks.” Economic Modelling 29 (5): 2011–15. https://doi.org/10.1016/J.ECONMOD.2012.04.022 [Google Scholar]) cointegration test, which accounts for multiple structural breaks, is applied for equilibrium relationship between the variables under review while the long run regression of dynamic ordinary least square (DOLS) is employed for long-run coefficients as estimation procedures. In order to account for the direction of causality flow, the Toda-Yamamoto (1995 Toda, H Y.., and Taku Yamamoto. 1995. Statistical inference in vector autoregressions with possibly integrated processes. Journal Of Econometrics 66 (1–2):22550. doi: 10.1016/0304-4076(94)01616-8.[Crossref], [Web of Science ®] [Google Scholar]) causality test is used for annual frequency data set spanning from 1971–2014. Empirical evidence from the Maki cointegration test shows that there exists a long-run equilibrium relationship between electricity consumption, carbon dioxide emissions and real gross domestic product per capita over the sampled period. The long-run regression suggests that there exist a positive statistically significant relationship between real income and electricity consumption. Thus, corroborating the electricity-led growth hypothesis. This result is supported by the causality test, as one-way causality is observed running from electricity consumption to real gross domestic product. Thus, this is suggestive to government administrators and policymakers that the Zimbabwean economy is electricity dependent. However, there is a tradeoff for environmental quality. As the increase in electricity consumption increases carbon dioxide emissions. The need for diversification of Zimbabwe energy portfolio to cleaner and environmentally friendly energy sources is recommended, given the world global consciousness for cleaner energy consumption.  相似文献   
22.
Environment, Development and Sustainability - In this study, non-carcinogenic health risks of thallium in grapevine exposed to mine waters of an abandoned mining region in Turkey were evaluated....  相似文献   
23.
The present study was conducted to compare the 137Cs, 40K, 232Th, and 238U activity concentrations in epigeic moss (Hypnum cupressiforme) and lichen (Cladonia rangiformis). The activity levels in 37 moss and 38 lichen samples collected from the Marmara region of Turkey were measured using a gamma spectrometer equipped with a high purity germanium (HPGe) detector. The activity concentrations of 137Cs, 40K, 232Th, and 238U in the moss samples were found to be in the range of 0.36-8.13, 17.1-181.1, 1.51-6.17, and 0.87-6.70 Bq kg−1 respectively, while these values were below detection limit (BDL)-4.32, 16.6-240.0, 1.32-6.47, and BDL-3.57 Bq kg−1 respectively in lichen. The average moss/lichen activity ratios of 137Cs, 40K, 232Th, and 238U were found to be 1.32 ± 0.57, 2.79 ± 1.67, 2.11 ± 0.82, and 2.19 ± 1.02, respectively. Very low 137Cs concentrations were observed in moss and lichen samples compared to soil samples collected from the same locations in a previous study. Seasonal variations of the measured radionuclide activities were also examined in the three sampling stations.  相似文献   
24.
Suspended sediment concentration (SSC) is generally determined from the direct measurement of sediment concentration of river or from sediment transport equations. Direct measurement is very costly and cannot be conducted for all river gauge stations. Therefore, correct estimation of suspended sediment amount carried by a river is very important in terms of water pollution, channel navigability, reservoir filling, fish habitat, river aesthetics and scientific interests. This study investigates the feasibility of using turbidity as a surrogate for SSC as in situ turbidity meters are being increasingly used to generate continuous records of SSC in rivers. For this reason, regression analysis (RA) and artificial neural networks (ANNs) were employed to estimate SSC based on in situ turbidity measurements. The SSC was firstly experimentally determined for the surface water samples collected from the six monitoring stations along the main branch of the stream Harsit, Eastern Black Sea Basin, Turkey. There were 144 data for each variable obtained on a fortnightly basis during March 2009 and February 2010. In the ANN method, the used data for training, testing and validation sets are 108, 24 and 12 of total 144 data, respectively. As the results of analyses, the smallest mean absolute error (MAE) and root mean square error (RMSE) values for validation set were obtained from the ANN method with 11.40 and 17.87, respectively. However these were 19.12 and 25.09 for RA. It was concluded that turbidity could be a surrogate for SSC in the streams, and the ANNs method used for the estimation of SSC provided acceptable results.  相似文献   
25.
Establishing intensive plantations of fast growing hardwood tree species that have high market values in the forest industry can narrow the gap between Turkey's demand and the supply of quality hardwood products. Black cherry (P. serotina Ehrh.) is a fast growing hardwood species with a high market value. Introducing and intensively growing black cherry (BC) in Turkey may significantly reduce the country's quality wood shortage. Adequate seed germination constitutes the first essential step for successful establishments. In this paper effects of different pretreatments, including artificial and natural stratification, on the seeds of different BC seed sources (SSs) were studied. Pretreatments had substantial effects on the dormancy breaking and germination behaviours of the SSs. Consecutive periods of complex warm and cold artificial stratification regimes longer than 90 days or natural stratification (where seeds were assumed to be naturally exposed to this complexity) resulted in best dormancy breaking and, in turn, germination among all pretreatments. Deeper dormancy and reduced germination rates of some BC seeds as the altitude of the source increases might suggest an ecological adaptive strategy of the species. BC may have deeper morphophysiological dormancy than is commonly believed. Seed size may have a positive effect on seed germination.  相似文献   
26.
Atlantic cedar (Cedrus atlantica Manetti) was grown, grafting onto the rootstocks of 2 years old Lebanon cedar (Cedrus libani L.). The mixture of polystimulin (PS) growth regulators was used to determine the effects on graft success and subsequent growth during three growing seasons. Scion clones had no effect on grafts success. PS increased the graft success by 20% in comparison to controls. PS-treated grafts burst their buds 18-20 days earlier than control grafts and increased shoot elongation. The PS-treated grafts had 4-5 cm longer shoots than controls at the end of three growing seasons. Thus, this research indicates the significance of PS-application on graft success and subsequent shoot growth on Atlantic cedar. It suggested that use of PS-treated grafts was more profitable than controls. Polystimulins which were used in small doses contributed significantly to the metabolism of Atlantic cedar seedlings after grafting.  相似文献   
27.
28.
Environmental Science and Pollution Research - Cold chain, which affects human health and quality of life, is applied for temperature-sensitive and perishable products. Any problems occurring in...  相似文献   
29.
Fish, a widely claimed healthy food for humans, could also pose problems to health due to (1) accumulation of pollutants, especially heavy metals, (2) presence of marine toxins such as tetrodotoxin, ciguatoxin or okadaic acid and (3) metabolic production of large amount of uric acid which may crystallize in kidney or in articulations. As tuna fish represents a large part of the traditional food in some countries, the possible impact of its consumption on public health was investigated, with special attention to biochemical and histological alterations related to the genital function. For that purpose, white or red muscle from tuna fish was added for 60 days to the diet of male rats, and attention was paid to biochemical and histological alterations related to the genital function. Feeding rats with white muscle, and much more markedly with red muscle known to be more metabolically active, resulted in (1) an elevated uric acid level in blood, (2) an increase in lead level in testis, (3) an atrophy of the genital tract, including testes, epididymis, prostate and seminal vesicles, (4) a lowering of plasma testosterone level, (5) a decrease in spermatozoids number and motility, (6) an oxidative stress in testes including an increase in lipids peroxidation level and enhanced superoxide-dismutase, catalase and glutathione-peroxidase activities. We conclude that consumption of tuna fish meat, especially the dark one, should be reduced.  相似文献   
30.
We present a case of esophageal and ileal duplications at 18 weeks of gestation. Transabdominal ultrasonography of the fetus showed multiple cystic masses of 12 to 17 mm in diameter and continuity with each other in the abdomen and a unilocular cystic mass of 15 mm in diameter in the posterior mediastinum. The cystic mass filled the abdominal cavity with signs of intestinal obstruction. The thoracic cystic mass was tubular, sausage-shaped and behind the heart, which was displaced to the antero-lateral wall of the chest. Amniocentesis revealed a normal fetal karyotype 46,XY. Peristaltic movements in the abdominal cystic structure at 30 weeks of gestation suggested dilated intestinal loops. Follow-up ultrasound examinations showed polyhydramnios with amniotic fluid index of 30 cm and gradual enlargement of the cystic structures to 50 mm in the abdomen and 30 mm in the posterior mediastinum at 38 weeks of gestation. A male infant weighing 3900 g was delivered. Postnatal ultrasonographic examination and the findings of magnetic resonance imaging also suggested enteric duplication cysts. Prenatal diagnosis allowed prompt neonatal evaluation and surgical treatment of the esophageal and the ileal duplications, which was confirmed by pathological examination. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
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