The human brain has been described as a complex system. Its study by means of neurophysiological signals has revealed the presence of linear and nonlinear interactions. In this context, entropy metrics have been used to uncover brain behavior in the presence and absence of neurological disturbances. Entropy mapping is of great interest for the study of progressive neurodegenerative diseases such as Alzheimer’s disease. The aim of this study was to characterize the dynamics of brain oscillations in such disease by means of entropy and amplitude of low frequency oscillations from Bold signals of the default network and the executive control network in Alzheimer’s patients and healthy individuals, using a database extracted from the Open Access Imaging Studies series. The results revealed higher discriminative power of entropy by permutations compared to low-frequency fluctuation amplitude and fractional amplitude of low-frequency fluctuations. Increased entropy by permutations was obtained in regions of the default network and the executive control network in patients. The posterior cingulate cortex and the precuneus showed differential characteristics when assessing entropy by permutations in both groups. There were no findings when correlating metrics with clinical scales. The results demonstrated that entropy by permutations allows characterizing brain function in Alzheimer’s patients, and also reveals information about nonlinear interactions complementary to the characteristics obtained by calculating the amplitude of low frequency oscillations.

We investigate the impact on intertemporal distribution caused by a change of policy from tax to deficit financing of public investment, using a simple theoretical framework which combines the one-period McGuire-Olson economy with the conventional long-run Solow economy. This theoretical framework provides a simple way to highlight some significant interdependencies between private and public investments as well as the negative impact of taxation on aggregate productivity, and to trace some possible transmission mechanisms between deficit financing policies and the long-run path of consumption per head. The main tentative (theoretical) result is that although under fairly acceptable assumptions the likely impact of a deficit financing policy is to benefit the present at the expense of the future, under equally acceptable assumptions concerning the possibility of an excessive macro private saving–investment propensity, and/or of a significant productivity loss due to the excess burden of taxation, the adverse intertemporal distributional impact of deficit financing might become negligible, or even disappear altogether.

Cucumis sativus is an important vegetable crop in the world. Agrobacterium mediated transgenic technology is an important means to study plant gene function and variety improvement. In order to further accelerate the transgenic research and breeding process of cucumber, aiming at the Agrobacterium mediated genetic transformation method of cucumber, this paper expounds the research progress and existing problems of Agrobacterium mediated transgenic cucumber from the aspects of influencing factors of cucumber regeneration ability, genetic transformation conditions and various added substances in the process, and prospects the future of improving the efficiency of cucumber genetic transformation and the application of safety screening markers, in order to provide reference for cucumber stress resistance breeding and fruit quality improvement.

In recent years, nanoporous alloys have presented the advantages of a large specific surface area, low density, and simple operation, and they have been widely used in the fields of catalysis, magnetism, and medicine. Nanoporous Pt-Si alloy was prepared by melt-spun and chemical dealloying, and was characterized by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscope, and transmission electron microscopy. Pt-Si alloys possess a three-dimensional bicontinuous structure and an average size of 5 nanometers. Compared with commercial Pt/C catalysts, nanoporous Pt-Si alloys exhibit excellent electrocatalytic activity and stability in ethanol-catalyzed oxidation reactions. It is taken into consideration to be a promising catalyst in direct ethanol fuel cells.

In this paper, a series of Li₃V₂(PO₄)₃/C composite nanofibers is prepared by a facile and environmentally friendly electrospinning method and calcined under different temperatures. The LVP nanofiber calcined under 900 ℃ exhibits the best electrochemical performance. The bicontinuous morphologies of LVP/CNF are the fibers shrunk and the LVP crystals simultaneously grown. At the range of 3.0–4.3 V, LVP/CNF obtained under 900 ℃ delivers the initial capacity of 135 mAh/g, close to the theoretical capacity of LVP. Even at high current density, the sample of LVP/CNF still presents good electrochemical performance.

The ultimate objective of the study was to investigate the effects of being landlocked on the living standards in Sub-Saharan African (SSA) countries from 1991 to 2019. Adopting the two-step estimation technique of System GMM (generalized method of moments), the study found that being landlocked has a negative and significant effect on the living standards in SSA countries when using GDP per capita as the living standard measure. Moreover, the historical living standard experiences of SSA countries have a positive and significant influence on the current living standard level. In addition, the population growth rate has a positive and significant effect on the living standards in SSA countries. On the other hand, the official exchange rate, broad money as a percentage of GDP, and inflation have a negative and significant effect on the living standards in SSA countries. Generally, the estimated result reveals the existence of a significant variation in the living standards in landlocked and coastal SSA countries. This study suggests that regional integration between landlocked and transit countries should be improved to minimize entry costs and increase access to global markets for landlocked countries. We argue that this study is of interest to landlocked and coastal countries to increase trade integration and promote the development of both groups, and it will contribute to the scarce empirical evidence.