This study examines the asymmetric link between fiscal decentralization, environmental innovation, and carbon emissions in highly decentralized countries. Our preliminary findings strictly reject the ...preposition of data normality and highlight that the observed relationship is quantile-dependent, which may disclose misleading results in previous studies using linear methodologies. Therefore, a novel empirical estimation technique popularized as Method of Moments Quantile Regression is employed that simultaneously deal with non-normality and structural changes. The results exhibit that fiscal decentralization significantly mitigates carbon emissions only at lower to medium emissions quantiles. On the other hand, environmental innovation reduces carbon emissions only at medium to higher emissions quantiles. Interestingly, the emissions-reducing effect of fiscal decentralization is highest for lower emissions quantiles and lowest for higher emissions quantiles. In contrast, the impact of environmental innovation is lowest for lower emissions quantiles and highest for higher emission quantiles. Economic growth and population increase carbon emissions, and their emissions-increasing effect are lowest for lower emissions quantiles and highest for higher emissions quantiles. Moreover, the heterogeneous panel causality test confirms a one-way causal association, implying that any policy intervention regarding fiscal decentralization and environmental innovation significantly affects carbon emissions.
Technological adaption and innovative activities foster small and medium enterprises (SMEs) growth by allowing production and process diversifications. Furthermore, open innovation practices, ...especially SMEs, rely on several firms’ specific attributes, and their impact varies accordingly. This study’s motivation is to explore the impact of technological adaptation and open innovation on SMEs run by women entrepreneurs and the challenges encountered in implementing open innovation. A sample of 580 questionnaires was sent to target SMEs, following the stratified random sampling technique, of which a complete 375 responses were duly received. The open innovation has been measured through eight innovative practices, reflecting the exploration and exploitation of technology in SMEs. This study found that women-owned enterprises were involved in many open innovation policies during the last five years. The result of this study indicated that there are no significant differences between manufacturing and industry regarding open innovation practices. Still, women-owned enterprises are more impressively engaged in open innovation practices. The research also identified that women-owned SMEs follow open innovation, mainly for market-related intentions, to compete with competitors and meet customers’ demands. The study contributes to the theoretical and practical implications. Further, the study is helpful for SMEs, researchers, practitioners, and decision-makers.
Tip-enhanced Raman spectroscopy (TERS) with sub-nanometer spatial resolution has been recently demonstrated experimentally. However, the physical mechanism underlying is still under discussion. Here ...we theoretically investigate the electric field gradient of a coupled tip-substrate system. Our calculations suggest that the ultra-high spatial resolution of TERS can be partially attributed to the electric field gradient effect owning to its tighter spatial confinement and sensitivity to the infrared (IR)-active of molecules. Particularly, in the case of TERS of flat-lying H₂TBPP molecules,we find the electric field gradient enhancement is the dominating factor for the high spatial resolution, which qualitatively coincides with previous experimental report. Our theoretical study offers a new paradigm for understanding the mechanisms of the ultra-high spatial resolution demonstrated in tip-enhanced spectroscopy which is of importance but neglected.
Realizing in situ simultaneous measurement of full vibrational modes in tip-enhanced Raman spectroscopy (TERS) is of immense importance for improving the ability of quantitative analysis and ...measurement accuracy of the molecular spectrum. In this study, the electric field gradient effect in the TERS system was theoretically investigated by using the finite element method. The respective contributions of electric field and electric field gradient to dipole Raman and gradient Raman modes in the TERS spectrum were quantitatively distinguished. By comparing the relative intensity ratio between electric field gradient and electric field, the TERS configuration could be optimized to achieve a maximum of gradient Raman modes. Theoretical results indicate that molecular symmetries strongly influence the molecular hyperpolarizability, which significantly influences the plasmonic electric field gradient effects. Our theoretical results could reveal the contributions of electric field and electric field gradient to molecular vibration modes, useful for the design of the TERS platform with more spectrum information.
The optimal gold-coated atomic force microscopy (AFM) tip-substrate system for tip-enhanced Raman spectroscopy (TERS) was designed theoretically and demonstrated experimentally. By optimizing the ...tip, excitation laser, and the substrate, the TERS enhancement factor can be tuned to as high as 9 orders of magnitude, and the spatial resolution could be down to 5 nm. Preliminary experimental results for AFM tips coated with gold layer of different thicknesses reveal that the maximum enhancement can be achieved when the thickness is about 60-80 nm, which is in good agreement with the theoretical prediction. Our results not only provide a deep understanding of the underlying physical mechanism of AFM tip-based TERS, but also guide the rational construction of a working AFM-TERS system with a high efficiency.
Wide applications of surface plasmon resonance rely on the in-depth understanding of the near-field distribution over a metallic nanostructure. However, precisely locating the strongest electric ...field in a metallic nanostructure still remains a great challenge in experiments because the field strength decays exponentially from the surface. Here, we demonstrate that the hot spot position for gold nanoparticles over a metal film can be precisely located using surface-enhanced Raman spectroscopy (SERS) by rationally choosing the probe molecules and excitation wavelengths. The finite difference time domain simulation verifies the experimental results and further reveals that the enhancement for the above system is sensitive to the distance between nanoparticles and the metal film but insensitive to the distance of nanoparticles. On the basis of this finding, we propose and demonstrate an approach of using a nanoparticles-on-metal film substrate as a uniform SERS substrate. This work provides a convenient way to probe the location of strong near-field enhancement with SERS and will have important implications in both surface analysis and surface plasmonics.
We theoretically investigate an optimized tip-film system that supports in-situ measurement of tip-enhanced Raman spectroscopy (TERS) and tip-enhanced fluorescence (TEF) of dye molecules. A scanning ...tunneling microscope (STM) is proposed to precisely control the tip-film distance, and thus in-situ measurement of TERS and TEF can be realized utilizing the specific surface plasmon resonance (SPR) properties of the tip-film system. Our calculations show that the optimized tip-film distance of 2 nm suggests a possibility of efficient acquisition of TERS and TEF in-situ. The calculated spatial resolution of TERS and spectral resolution of TEF can be down to 6.5 nm and 10 nm, respectively. Our theoretical results may find promising application in developing multiple functional nano-spectroscopy through which Raman and fluorescence can be measured in-situ at the nanoscale level.
Parkinson's disease is a common neurodegenerative disease with movement disorders associated with the intracytoplasmic deposition of aggregate proteins such as α-synuclein in neurons. As one of the ...major intracellular degradation pathways, the autophagy-lysosome pathway plays an important role in eliminating these proteins. Accumulating evidence has shown that upregulation of the autophagy-lysosome pathway may contribute to the clearance of α-synuclein aggregates and protect against degeneration of dopaminergic neurons in Parkinson's disease. Moreover, multiple genes associated with the pathogenesis of Parkinson's disease are intimately linked to alterations in the autophagy-lysosome pathway. Thus, this pathway appears to be a promising therapeutic target for treatment of Parkinson's disease. In this review, we briefly introduce the machinery of autophagy. Then, we provide a description of the effects of Parkinson's disease-related genes on the autophagy-lysosome pathway. Finally, we highlight the potential chemical and genetic therapeutic strategies targeting the autophagy-lysosome pathway and their applications in Parkinson's disease.
Stochasticity and ambiguity are two aspects of uncertainty in economic problems. In the case of investments in risky assets, this uncertainty is manifested in the uncertainty of future returns. On ...the contrary, the complexity of the economic phenomenon itself and the ambiguity inherent in human thinking and judgment are characterized by indistinct boundaries. For the same problem, research from different perspectives can often provide us with more comprehensive and systematic information. Currently, the expected value of return or the variance representing risk is still used as a rational investment criterion for both single-stage portfolios and multistage portfolios. However, in general, the greater the expected return of an investor, the greater the risk he should take. Different investors have different requirements for profitability, but regardless of their expected return, they always hope to find a set of portfolios that maximize the probability of achieving the expected rate of return. In this paper, after analyzing the development of portfolio investment theory research, we take fuzzy information processing as the entry point and systematically discuss the theory and methods of fuzzy modeling of portfolio investment decision-making from the perspective of fuzziness around the portfolio investment decision-making process. The results of the empirical analysis show that the existence of basis constraints affects investors’ investment strategies as well as their final returns, but there is a limit to the influence of basis constraints on portfolio performance, and investors can obtain optimal investment returns by selecting a reasonable number of securities to form a portfolio based on the characteristics of different securities.