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This study analyzes the causal associations between economic growth (GDP) and biomass energy consumption (BIO) in the US, UK, and BRICS countries for the period 1990 to 2020 in time-frequency space. The use of wavelets is what distinguishes our approach, i.e., cross wavelet transform, wavelet coherence, and the wavelet-based Granger causality method proposed by Olayeni (2016), which quantifies the causal associations in the time-frequency space. The results uncover that the causal relationships between GDP and BIO are not uniform across time and frequency. In fact, there is a positive relationship between GDP and BIO indicators in the BRICS countries in the medium and long term and in the USA and UK in the short term throughout the research period. In addition, a bidirectional causal effect between GDP and BIO exists in China, Brazil, and India, while there is no long-run causal relationship between GDP and BIO in India and South Africa. The causal impacts of economic growth on biomass energy usage are more pronounced in these countries than in the opposite direction, especially over longer time horizons. The key conclusion is that these countries should boost their biomass energy consumption to promote economic growth and reduce energy reliance.
Asunto(s)
Dióxido de Carbono , Desarrollo Económico , Biomasa , Brasil , Dióxido de Carbono/análisis , China , Países Desarrollados , India , Energía Renovable , Sudáfrica , Análisis de OndículasRESUMEN
Environmental quality and economic activity have a strong relationship. Carbon emissions remain one of the world's most dangerous environmental issues. Both international and local governments are developing initiatives to address this problem. Capitalizing on the limitations of the existing literature, this article investigates the dynamic nexus of financial development, economic growth, and globalization on carbon dioxide emissions in Vietnam for 1990-2020 using the quantile-on-quantile regression. The findings unveil a positive feedback link between globalization and carbon dioxide emissions at the middle and high quantiles. In addition, there is a negative nexus between financial development and carbon emissions at most quantiles, while CO2 emissions and economic growth have a positive association at all quantiles. More importantly, our empirical results also provide the bidirectional causality between financial development, economic growth, globalization, and carbon dioxide emissions in Vietnam at different quantile levels. The consistency of the outcomes uncovers that the findings are trustworthy and appropriate for guiding policy to reduce CO2 emissions in Vietnam. Therefore, they can help policymakers understand how financial development and globalization can achieve sustainable economic growth and tackle environmental issues in this country.
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Dióxido de Carbono , Desarrollo Económico , Dióxido de Carbono/análisis , Internacionalidad , Políticas , VietnamRESUMEN
Background: The aim of this study was to confirm the morphometry of the anterolateral thigh (ALT) pedicle and the location of the perforators in the adult Vietnamese population. Material and methods: Forty dissections of the thigh were carried out in 20 Vietnamese dedicate cadavers. Including 13 cadavers were fixed by Formalin and 7 cadavers were fixed by fridge. The number, origin, location of the perforators and the diameter of the ALT pedicles were studied and measured. Results: The length of the thigh was 39.9 ± 2.8 cm. 39/40 cases (97.5%) were a perforator of a 4 cm circle drawn at the midpoint thigh. There were 161 perforators. In 82.7% of perforators were musculocutaneous perforators and 17.3% perforators were septocutaneous perforators. There were 5 types of vascular pedicles. Type 1: the perforators originated from the descending branch were 65%; Type 2: from the oblique branch were 22.5%; Type 3: from the transverse branch were 5%; Type 4: from profunda femoris were 5%; Type5: from femoral artery were 2,5%. The average length of the flap pedicle was 11.6 ± 2.4 cm, the diameter of the artery was 2.51 ± 0.52 mm, the vein was 2.95 ± 0,56 mm and 2.18 ± 0,46. Conclusion: The ALT flap is a constant vascular supply, a long pedicle with a suitable diameter for anastomoses. The ALT can be harvest widely and reliable with a perforator of a 4 cm circle drawn at the midpoint thigh.
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This paper represents an analysis of the spillover effects and time-frequency connectedness between crude oil prices and agricultural commodity markets using both the spillover index of Diebold and Yilmaz (2012) and the wavelet coherence model to evaluate whether the time-varying return spillover index exhibited the intensity and direction of transmission during the Covid-19 outbreak. Overall, the current results shed light on that in comparison with the pre-Covid-19 period, and the return spillover is more apparent during the Covid-19 crisis. However, levels of the intensity of this relationship vary through the period of research, with several intervals witnessing both negative and positive interactions. Further, our findings indicate significant heterogeneity among agriculture commodity markets in the degree of spillover to crude oil prices over time, amplifying our understanding of the economic channels through which the agriculture commodity markets are correlated. More importantly, there exist significant dependent patterns about the information spillovers across the crude oil and agriculture commodity markets might provide prominent implications for portfolio managers, investors, and government agencies.
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The Covid-19 crisis has been spread rapidly throughout the world so far. However, how deep and long the turbulence would depend on the success of solutions taken to deter the spread of Covid-19, the impacts of government policies may be prominent to alleviate the current crisis. In this article, we investigate the spillover effects and time-frequency connectedness between S&P 500, crude oil prices, and gold asset using both the spillover index of Diebold and Yilmaz (2012) and the wavelet coherence to evaluate whether the time-varying dynamic return spillover index exhibited the intensity and direction of transmission during the Covid-19 outbreak. Overall, the present results shed light on that in comparison with the pre-Covid-19 period, and the return transmissions are more apparent during the Covid-19 crisis. More importantly, there exist significant dependent patterns about the information spillovers among the crude oil, S&P 500, and gold markets might provide significant implications for portfolio managers, investors, and government agencies.