To explore the potential role of polymers in the development of drug-delivery systems, this study investigated the use of β-cyclodextrin (β-CD), carboxymethyl cellulose (CMC), acrylic acid (AA) and ...N' N'-methylenebis-acrylamide (MBA) in the synthesis of hydrogels for controlled drug delivery of acyclovir (ACV). Different proportions of β-CD, CMC, AA and MBA were blended with each other to fabricate hydrogels via free radical polymerization technique. Fourier transform infrared spectroscopy (FTIR) revealed successful grafting of components into the polymeric network. Thermal and morphological characterization confirmed the formation of thermodynamically stable hydrogels having porous structure. The pH-responsive behaviour of hydrogels has been documented by swelling dynamics and drug release behaviour in simulated gastrointestinal fluids. Drug release kinetics revealed controlled release behaviour of the antiviral drug acyclovir in developed polymeric network. Cross-linked β-cyclodextrin and carboxymethyl cellulose hydrogels can be used as promising candidates for the design and development of controlled drug-delivery systems.
Countries enact environmental regulations to achieve sustainable development and ecological sustainability. However, environmental regulations do not guarantee environmental sustainability unless ...implemented efficiently. Furthermore, political institutions play a key role in the formulation and management of environmental regulations. This research examines the relationship between democracy, environmental regulations, economic growth, and ecological footprint (EF) in the panel of G7 nations from 1985 to 2017. Second generation econometric techniques are used to analyze the data. The empirical evidence indicates that economic growth enhances EF while democracy and environmental regulations positively contribute to ecological sustainability by reducing EF. The causal outcomes reveal that democracy Granger causes EF and renewable energy indicating that democracy curbs environmental degradation and stimulates the share of renewables. Further, democracy and environmental regulations Granger cause each other. Lastly, the implication of these findings for sustainable development and ecological sustainability are discussed.
This study aims to examine the impact of public-private partnerships (PPP) investment in energy, technological innovations (TI), economic growth (EG), exports, and foreign direct investment (FDI) on ...CO
2
emissions in Brazil over the period from 1984 to 2018. In doing so, we employ the Ng-Perron unit root test to examine the stationarity and autoregressive lag distributed (ARDL) model for cointegration between CO
2
emissions and its determinants. The outcomes are as follows: first, in the long run, the PPP investment in energy deteriorates the environmental quality by increasing CO
2
emissions, while TI has a significant negative effect on CO
2
emissions. It is also found that the exports and FDI degrade the environmental quality and the relationship between EG and CO
2
emissions is inverted U-Shaped, presence of the EKC hypothesis. Second, in the short run, PPP investment in the energy sector is negatively influencing, while TI has a positive association with carbon emissions. The empirical findings provide new insights for policymakers to regulate PPP investment in the energy sector for the improvement of environmental quality in Brazil.
Graphical abstract
This study examines the effect of financial development (FD) and foreign direct investment (FDI) on the environmental quality for the panel of 90 belt and road countries from 1990 to 2017. This study ...advances the knowledge of financial development by using the new comprehensive index, which is based on access, depth, and efficiency of financial markets and financial institutions and incorporated foreign direct investment as an important determinant of environmental quality. By applying the Driscoll-Kraay standard error pooled ordinary least square method, the empirical findings reveal that FD deteriorates the environmental quality by increasing the CO
2
emissions, while FDI improves environmental quality and the relationship between economic growth (EG) and CO
2
emissions is inverted U-shaped, i.e., presence of EKC hypothesis. The energy consumption and urbanization pollute the environment, while trade openness enhances the quality of the environment. Furthermore, the Dumitrescu-Hurlin (DH) panel causality test result confirms that the bidirectional causality exists among FD, trade openness, energy consumption, and urbanization with CO
2
emissions. The empirical results provide new insights for policymakers and also have several implications for the betterment of environmental quality.
In 2020, China promised to achieve carbon peaking by 2030 and carbon neutrality by 2060, and these targets are famous as “Goal 3060” in China. Chinese resource-based cities are concerned about the ...realization of Goal 3060 to practice national action against environmental change. In this paper, this study evaluates the impact of population, economic growth, energy intensity, industrial structure, fixed asset investment, and urbanization level on carbon emissions in Chinese cities. To do so, the paper divides 36 Chinese cities into four types (growing city, mature city, recessionary city, and regenerative city) from 2003 to 2017 by factor investigation according to the diverse development stages. The extended STIRPAT model is used to assess the impact of various factors on CO
2
emissions in the Yellow River basin and diverse city levels. The panel regression analysis was conducted for the basin as a whole and cities at different development stages through a fixed-effects model and a linear regression model with Driscoll-Kraay standard errors. The results show that (1) the total carbon emissions in the Yellow River basin continued to climb during the study period. However, the growth rate slowed down significantly after 2012. In addition, there are differences in the total carbon emissions and growth rate of different cities. (2) Population, real GDP, energy intensity, industrial structure, and fixed asset investment all have a significant positive impact on carbon emissions in the overall basin except the urbanization level which has a significant negative influence on carbon emissions. (3) There is heterogeneity in the influencing factors of carbon emissions in resource-based cities at various development stages. Based on these results, corresponding policies are proposed for different types of cities to help resource-based cities achieve the 3060 dual carbon goal.
To study the economic and environmental effects of human capital, previous studies measure human capital based on education; however, this approach has many shortcomings because not all educated ...people are innovative human capital. Hence, this study introduces the concept of innovative human capital by developing a new index that measures human capital based on the number of patents every one million R&D staff full-time equivalent. After this, this paper studies the impact of innovative human capital on CO2 emissions in China. The provincial panel data of 30 Chinese provinces from 2003 to 2017 is analyzed using the fixed effect, ordinary least squares, and the system generalized method of moments (SYS-GMM). The analysis revealed that innovative human capital alleviates environmental deterioration in China. The findings unfold the existence of the environmental Kuznets curve (EKC) considering innovative human capital in the model. It implies that Chinese economic development will eventually support environmental sustainability if China continues to develop its innovative human capital. Among the control variables, economic structure, population density, and energy intensity stimulate environmental degradation by increasing CO2 emissions. However, FDI has a negative relationship with CO2 emissions. Lastly, the study proposes comprehensive policies to increase innovative human capital for environmental sustainability.
•Endophytic bacteria isolated from cucumber showed plant growth promoting ability.•Endophytic bacteria regulated plant metabolites compared to uninoculated plants.•50 % metabolites had higher ...concentration in either or both bacteria-applied plants.
Endophytic bacteria have been explored for their role in plant growth promotion, however, not much has been explored in cucumber. The metabolomic response of plants to application of such microbes also remains largely unknown. Thus, we investigated the application of endophytic bacteria to cucumber to infer their role in plant growth promotion and document metabolome response. The lowest healthy leaf-stalks were sampled from four differently sourced cucumber plants, and endophytic bacteria were isolated after surface disinfection. Initial plant growth-promoting (PGP) screening was performed to identify PGP strains out of numerous isolates, and five strains (Strains 4=Curtobacterium spp., 72=Brevibacillus spp., 167=Paenibacillus spp., 193=Bacillus spp., and 227=Microbacterium spp.) were selected based on their contribution to root growth compared with the control. The selected strains were further evaluated in pot experiments, axenic PGP trait assays, and metabolomic analysis. Results revealed that the selected isolates possessed different qualitative characteristics among indole acetic acid, siderophore production, phosphate solubilization, and 1-aminocyclopropane-1-carboxylate (ACC)-deaminase and nifH genes, and all isolates significantly enhanced plant growth in both pot experiments compared with the uninoculated control and fertilizer control. Metabolomic profiling revealed that both strains affected the plant metabolomes compared with the uninoculated control. Around 50 % of the metabolites explored had higher concentrations in either or both bacteria-applied plants compared with the uninoculated control. Differences were observed in both strains’ regulation of metabolites, although both enhanced root growth near equally. Overall, endophytic bacteria significantly enhanced plant growth and tended to produce or induce release of certain metabolites within the plant endosphere.
The major criteria that control pile foundation design is pile bearing capacity (Pu). The load bearing capacity of piles is affected by the various characteristics of soils and the involvement of ...multiple parameters related to both soil and foundation. In this study, a new model for predicting bearing capacity is developed using an extreme gradient boosting (XGBoost) algorithm. A total of 200 driven piles static load test-based case histories were used to construct and verify the model. The developed XGBoost model results were compared to a number of commonly used algorithms—Adaptive Boosting (AdaBoost), Random Forest (RF), Decision Tree (DT) and Support Vector Machine (SVM) using various performance measure metrics such as coefficient of determination, mean absolute error, root mean square error, mean absolute relative error, Nash–Sutcliffe model efficiency coefficient and relative strength ratio. Furthermore, sensitivity analysis was performed to determine the effect of input parameters on Pu. The results show that all of the developed models were capable of making accurate predictions however the XGBoost algorithm surpasses others, followed by AdaBoost, RF, DT, and SVM. The sensitivity analysis result shows that the SPT blow count along the pile shaft has the greatest effect on the Pu.
This study aims to analyze the effects of natural resources, human capital, financial development, industrialization, technological progress, and international trade on the economic growth of the ...Next Eleven countries between 1990 and 2019. The novelty of this study lies in its approach to explore the indirect economic growth impacts of human capital development via the transmission channel of the natural resource utilization in these counties. The econometric methods involved are robust for accounting the cross-sectional dependence and slope heterogeneity concerns in the data. The results authenticate the resource curse hypothesis since higher natural resources rent are found to inhibit economic growth of the Next Eleven nations. In contrast, human capital development, financial development, industrialization, technological innovation and international trade participation are found to synthesize economic growth. Besides, another interesting finding in this study shows that human capital and natural resources jointly exert positive impacts on economic growth. Hence, it can be said that human capital development assists to mitigate the resource curse impacts in the case of the Next Eleven countries. Therefore, these findings necessitate the pertinence of boosting investments in human capital development, enhancing the strength of the financial sector, expediting industrialization, facilitating technological innovation, and amplifying international trade volumes for achieving higher economic growth in the Next Eleven countries. More importantly, human capital development should be prioritized for transforming the curse of the natural resources into blessing for these nations.
Display omitted
•Resources curse hypothesis is tested for Next 11 countries.•Natural resources rent deteriorate economic growth.•Human capital directly and indirectly synthesize economic growth.•Human capital development can overcome resource curse.
China's rapid expansion of digital financial inclusion in the last few years has dramatically augmented the accessibility and affordability of financial services, predominantly serving formerly ...financially excluded people, and positively contributes to higher economic growth. Despite the importance of digital financial inclusion in promoting economic growth, empirical evidence is relatively thin. Moreover, none of the studies has considered human capital in the nexus. Therefore, this study examines the impact of digital financial inclusion and human capital on China's provincial economic growth. Unlike previous studies, this study uses the new proxy of digital financial inclusion based on breadth of coverage, depth of usage, and digitalization level. The empirical findings show that digital financial inclusion and human capital significantly affect China's provincial economic growth. Based on this study's findings, we recommend investment in human capital development and, at the same time, upgrading digital financial inclusion to attain higher economic growth.
PDF
