Level Index Research Articles

CircFOXN2 alleviates glucocorticoid- and tacrolimus-induced dyslipidemia by reducing FASN mRNA stability by binding to PTBP1 during liver transplantation.

We aimed to examine impacts and functional mechanism of circular RNA forkhead box N2 (FOXN2) in tacrolimus (TAC)- and dexamethasone (Dex)-induced lipid metabolism disorders. RNA level and protein contents in TAC, Dex, or combined TAC- plus Dex-treated patients and Huh-7 cells were measured utilizing quantitative real-time (qRT)-PCR and western blotting assays measured the formation of lipid droplet. Total cholesterol (TC) and triglyceride (TG) levels were determined using corresponding commercial kits and Oil red O staining. RNA immunoprecipitation and RNA pull-down verified the binding relationship among circFOXN2, polypyrimidine tract binding protein 1 (PTBP1) and fatty acid synthase (FASN). Male C57BL/6 mice were used to establish a dyslipidemia mouse model to validate the discoveries at the cellular level. Dex treatment significantly promoted TAC-mediated increase of TC and TG in serum samples and Huh-7 cells. Moreover, circFOXN2 was reduced but FASN was elevated in TAC-treated Huh-7 cells, and these expression trends were markedly enhanced by Dex cotreatment. Overexpression of circFOXN2 could reverse the accumulation of TC and TG and the upregulation of FASN and sterol regulatory element binding transcription factor 2 (SREBP2) mediated by Dex and TAC cotreatment. Mechanistically, circFOXN2 reduced FASN mRNA stability by recruiting PTBP1. The protective roles of circFOXN2 overexpression on lipid metabolism disorders were weakened by FASN overexpression. In vivo finding also disclosed that circFOXN2 greatly alleviated the dysregulation of lipid metabolism triggered by TAC plus Dex. CircFOXN2 alleviated the dysregulation of lipid metabolism induced by the combination of TAC and Dex by modulating the PTBP1/FASN axis.NEW & NOTEWORTHY Collectively, our experiments revealed for the first time that circFOXN2 alleviated the Dex- and TAC-induced dysregulation of lipid metabolism by regulating the PTBP1/FASN axis. These findings suggested that circFOXN2 and FASN might be candidate targets for the treatment of Dex- and TAC-induced metabolic disorders.

Research on Enterprise Digital-Level Classification Based on XGBoost Model

Digital knowledge and information have become significant production variables that have permeated all aspects of life and play a leading and supporting role in the growth of the real economy as the digital economy has developed. Through field research and web research, this study identifies digital-economy-related enterprises as the survey object; summarizes the fundamental information for these enterprises, their level of digitization, and the dilemma and demands of digital-level advancement; and generates survey data for 1936 enterprises. On the basis of these data, this study extracts the elements that influence the improvement of the enterprises’ digital level, applies statistical knowledge and machine learning techniques, and derives an enterprise digitization level index system and associated index score for enterprise digitization level. The experimental results indicate that the region, the time of establishment, the nature of ownership, the number of employees, R&D investment, being a national high-tech enterprise, and the establishment of digital transformation management departments have major effects. The AUC value of the XGBoost model modeled using all feature variables has achieved certain results, and the five assessment indices of the model have been enhanced to varying degrees, with the AUC being 0.9263.

Research on health evaluation model for elevator based on analytic hierarchy process

Elevator safety has been widely concerned by the society. In order to evaluate the health of elevator visually, a quantitative evaluation model based on analytic hierarchy process is proposed. The value of elevator health is determined according to the failure frequency, inspection result, maintenance etc. The weight value of each factor is calculated by analytic hierarchy process which based on two level index system. Besides, the subtraction method was added to the analytic hierarchy process for improving its operability. The practice is conducted to verify the evaluation method is feasible which is applied to risk warning for elevator.

Entropy Optimization, Generalized Logarithms, and Duality Relations.

Several generalizations or extensions of the Boltzmann-Gibbs thermostatistics, based on non-standard entropies, have been the focus of considerable research activity in recent years. Among these, the power-law, non-additive entropies Sq≡k1-∑ipiqq-1(q∈R;S1=SBG≡-k∑ipilnpi) have harvested the largest number of successful applications. The specific structural features of the Sq thermostatistics, therefore, are worthy of close scrutiny. In the present work, we analyze one of these features, according to which the q-logarithm function lnqx≡x1-q-11-q(ln1x=lnx) associated with the Sq entropy is linked, via a duality relation, to the q-exponential function characterizing the maximum-entropy probability distributions. We enquire into which entropic functionals lead to this or similar structures, and investigate the corresponding duality relations.

The Impact of the Digital Economy on Innovation: New Evidence from Panel Threshold Model

The digital economy has aroused widespread concern. This paper studies the impact of the digital economy on innovation using a panel threshold model. Taking 30 provinces, municipalities, and autonomous regions in China as the research object, the time span is from 2013 to 2019. The data are from the National Bureau of Statistics of China (NBSC), China National Intellectual Property Administration (CAIPA), the China Stock Market and Accounting Research (CSMAR), and the Ministry of Industry and Information Technology (MIIT)of China. Data analysis is performed with ArcGIS 10.2 and STATA 16 software. The influence mechanism of digital economy on innovation is innovatively analyzed from the aspects of innovation elements, innovation tools, innovation subjects, and innovation environment. A digital economy development level index system is constructed using the entropy method, and the development level of China’s digital economy in time and space is analyzed. On this basis, the nonlinear impact of digital economy on innovation, i.e., the threshold effect, is innovatively studied using the panel threshold model. It is found that China’s digital economy develops rapidly, but there is a serious spatial imbalance, and there are great differences in the different dimensions of the digital economy. At the same time, the impact of digital economy on innovation has a double threshold effect with industrial structure as the threshold variable and a single threshold effect with urbanization level as the threshold variable. Specifically, the promoting effect of digital economy on innovation increases with the optimization of industrial structure or the improvement of urbanization level. This study enriches the theoretical research on the impact of digital economy on innovation, and it has important support and reference value for China’s development of digital economy and improvement of innovation capacity.

Caputo-Hadamard fractional differential equations on time scales: Numerical scheme, asymptotic stability, and chaos.

This study investigates Caputo-Hadamard fractional differential equations on time scales. The Hadamard fractional sum and difference are defined for the first time. A general logarithm function on time scales is used as a kernel function. New fractional difference equations and their equivalent fractional sum equations are presented by the use of fundamental theorems. Gronwall inequality, asymptotical stability conditions, and two discrete-time Mittag-Leffler functions of Hadamard type are obtained. Numerical schemes are provided and chaos in fractional discrete-time logistic equation and neural network equations are reported.

A Note on the Insecurity of Cryptosystems Based on Chebyshev Polynomials

The security of cryptosystems based on Chebyshev recursive relation, [Formula: see text], relies on the difficulty to find the large degree [Formula: see text] of Chebyshev polynomial for given parameters. But this relation cannot be used to evaluate [Formula: see text], if [Formula: see text] is very large. We investigate three other methods: matrix-multiplication-based evaluation, halve-and-square evaluation, and root-extraction-based evaluation. We find they have the same complexity [Formula: see text] over finite field [Formula: see text]. The result shows that the hardness of some cryptosystems based on modular Chebyshev polynomials is almost equivalent to the general discrete logarithm. This partially answers the question why such chaos-based cryptosystems have rarely been put into practice.

Study on the seismic lethal level of buildings and seismic disaster risk in Guangzhou, China

Seismic disaster risk assessment results are an important way to reduce disaster losses and casualties. In this article, a seismic disaster risk assessment method is constructed based on the lethal level, and a quantitative assessment of the earthquake disaster risk in Guangzhou is carried out. There are four typical building types in this study area: brick-wood structures, brick-concrete structures, reinforced concrete structures, and civil structures. Typical building structural components (vertical load-bearing component, ring beam, mortar of infilled wall, roof or floor structure, foundation, height of building, nonstructural component, anti-seismic joint or other anti-seismic measures) are selected to build the lethal level index system of buildings. On the basis of the field survey, a lethal level of 431 survey points is obtained. The average lethal level in urban areas is 0.3476, and in rural areas is 0.4198, the overall lethal level of each township is 0.389, and the errors between the urban and rural areas are 0.0414 and 0.0308, and the fitting results coefficient of determination (R2) values are 0.6803 and 0.6714, respectively, the results is good. Furthermore, considering the seismic hazard (peak ground acceleration, PGA), population exposure and lethal level, the seismic disaster risk distribution of the Guangzhou area is determined. Under different intensities, the risk of death has shown obvious characteristics, as the intensity increases, the number of possible deaths increases rapidly, ranging from a few to several thousand, the higher risk areas are relatively fixed, generally mainly located in the central city, the quantitative assessment results of disaster risk also have obvious directivity. The areas with the highest risk are located in most areas of Tianhe District, Liwan District and Haizhu District, the highest grid death result is more than 1; the lethal level of Baiyun District and Huangpu District is low, but the death risk is also higher, generally between 0.5 and 1, in rural areas in the southern and northern regions of Guangzhou, the risk is relatively low, generally between 0 and 0.5. The distribution map of seismic disaster risk can provide solid scientific and technological support for the government to investigate potential risk points.

A research on measure of regional agricultural economic development level based on Entropy-CRITIC method and K-Means

The continuous promotion of China's rural revitalization strategy has not put forward higher requirements for the development of overall agriculture. However, it is difficult to regulate the status quo of unbalanced regional economic development. Based on this, this paper selects the provinces and cities in Sichuan Province from 2018-2020 as the research object and constructs a regional agricultural economic development level index system, and then uses the entropy value CRITIC method to assign weights and carry out linear weighting to obtain the regional agricultural economic development level index from the consideration of the volatility and conflict of data. Then, K-Mean clustering was used to analyze the level of agricultural economic development in Sichuan Province from two dimensions: geographical and temporal. The empirical results show that: from the time dimension, the comprehensive index of high-quality agricultural economic development in most regions shows a trend of increasing year by year since 2018-2020; from the geographical dimension, it shows the form of strong in the north and weak in the south, and strong in the center and weak in the fourth. Finally, this paper puts forward relevant suggestions for the development of regional agricultural economy in conjunction with the actual situation.

A Study on the logarithm correction of black hole entropy

The logarithm correction of black hole entropy is important in understanding the essence of black hole entropy, providing a more accurate entropy calculation. We reviewed the mainstream method of logarithm correction of black hole entropy, including quantum loop gravity correction, conformal field theory correction, and classical thermal correction. Specifically, the correction of quantum loop gravity presents a stable general expression of logarithm correction, which only depends on the surface area of the black hole and solves the problem of meaningless entropy solution under a large length scale. Besides, the correction of the Cardy formula of conformal field theory is limited for the third term in depends on the mass of the black hole, which will finally lead to the unstable coefficient before the correction term. Finally, the correction deduced by the classical thermal method also gives a general expression of black hole entropy. In contrast, the entropy of BTZ black hole has a different coefficient before the logarithm term comparing to other kinds of the black hole. These results shed light for the research in general logarithm correction of black hole entropy, which is suitable for all kinds of black holes.

Optimal Lp filtering for discrete‐time non‐Gaussian dynamic systems

This paper investigates the L p filtering problem for linear dynamic systems. The main objective is to discuss the optimal filter for non-Gaussian systems. The filter structure is obtained by extension of the maximum a posteriori estimation problem for general norm exponential probability density functions. The obtained filter has a linear structure, and two different algorithms are proposed for 1 ≤ p < ∞ and p = ∞ . In the following, the choice of p has been discussed based on the asymptotic distribution and the central limit theorem as well as the kurtosis of error probability density function. Both of them confirm that the L 2 filter is optimal for Gaussian systems, and the L p filter, for p < 2 , has the best performance for the systems with leptokurtic error distributions, and for p > 2 , it is the best for the systems with platykurtic error distributions. In this regard, it is shown that the L 1 and L ∞ filters have the best MSE performance for the systems with Laplacian and uniform error probability distribution functions, respectively. Simulation results verify the superior performance of the proposed filtering approach for linear time-invariant and time-varying systems.

Study on risk assessment of EPC water conservancy project based on entropy weight set pair analysis

In recent years, EPC mode has been developed rapidly in water conservancy projects. However, due to the complex construction conditions, long construction period and easy to be affected by natural conditions of water conservancy project, the general contractor of EPC project is faced with greater risks. If the risk analysis is not enough, the project profit of the contractor will be lower than expected or even loss. Water conservancy project risk indicators are qualitative indicators, which are easily affected by subjective factors and quantitative uncertainty in the process of index quantification. In this paper, combined with the relevant research at home and abroad, combined with the characteristics of water conservancy projects, the establishment of water conservancy project risk assessment level index system. The set pair analysis model which can comprehensively evaluate the connection degree between risk index and risk level and the entropy weight model which can reflect the information content of the index are introduced into the risk evaluation of EPC water conservancy project. The evaluation results show that the entropy weight method can calculate the weight of each risk index in the risk level, and the set pair analysis method can comprehensively evaluate the connection degree between the risk index and different risk levels.

Organic thin film thickness-dependent photocurrents polarity in graphene heterojunction phototransistor

To overcome the weak absorption deficiency of 2D materials, combining bilayer/bulk heterojunction and 2D materials in a photoconductive framework facilitates the separation and transfer of photo-generated carriers for prominent performance photo-detector. Nevertheless, apart from improving the inferior built-in electric field, the multilayer device may suffer a low efficiency due to depletion loss considering the effective exciton length limitation. Here, we demonstrate the thickness-dependent photocurrent polarity based on a bilayer enhanced graphene/C60/ZnPc phototransistor. A fast response time down to 7.29 μs and a responsivity of 6537 A/W are achieved in the device with the help of type-II band alignment and valid interfaces between organic layers. Moreover, three controlled thicknesses of intermediate charge transfer layer are investigated for the purpose of probing the transfer direction in multilayer heterojunction, which suggests that the photocurrent polarity is highly related to the thickness of C60 and even input optical power density. Owing to the phenomena of photocurrents polarity, a distinct bending curve of responsivity-power density relation is observed near the positive-negative altering point compared to general logarithm linear relation in most photoconductive devices. Our results may enable further exploration of charge transfer mechanism in multilayer system and development of high speed photoconductive transistor.

Diverse accurate computational solutions of the nonlinear Klein–Fock–Gordon equation

This manuscript handles the nonlinear Klein–Fock–Gordon (KFG) equation by applying two recent computational schemes (generalized exponential function (GEF) and generalized Riccati expansion (GRE) methods) to construct abundant novel wave solutions The considered model is the generalized form of the well-known nonlinear Schrödinger equation which is considered a quantized version of the relativistic energy-momentum relation. The accuracy of the employed analytical schemes by showing the matching between computational and approximate solutions and calculating the absolute value of error between these solutions. This matching is investigated by employing the variational iteration (VI) method to show the precision of the used schemes with the previously published solutions. The physical characterization of the evaluated solutions has explained through some distinct sketches in 2D, 3D, contour, polar, and spherical plots. The originality and novelty of our investigation have been checked by comparing our solution’s accuracy with previous other solutions’ accuracy.

On General Exponential Weight Functions and Variation Phenomenon

General weighted exponential distributions including modified exponential ones are widely used with great ability in statistical applications, particularly in reliability. In this paper, we investigate full exponential weight functions and their extensions from any nonnegative continuous reference weighted distribution. Several properties and their connections with the recent variation phenomenon are then established. In particular, characterizations, weightening operations and dual distributions are set forward. Illustrative examples and concluding remarks are extensively discussed.

Ex-vivo cultured human corneoscleral segment model to study the effects of glaucoma factors on trabecular meshwork.

Glaucoma is the second leading cause of irreversible blindness worldwide. Primary open angle glaucoma (POAG), the most common form of glaucoma, is often associated with elevation of intraocular pressure (IOP) due to the dysfunction of trabecular meshwork (TM) tissues. Currently, an ex vivo human anterior segment perfusion cultured system is widely used to study the effects of glaucoma factors and disease modifying drugs on physiological parameters like aqueous humor (AH) dynamics and IOP homeostasis. This system requires the use of freshly enucleated intact human eyes, which are sparsely available at very high cost. In this study, we explored the feasibility of using human donor corneoscleral segments for modeling morphological and biochemical changes associated with POAG. Among the number of corneas donated each year, many are deemed ineligible for transplantation due to stringent acceptance criteria. These ineligible corneoscleral segments were obtained from the Lions Eye Bank, Tampa, Florida. Each human donor anterior corneoscleral segment was dissected into four equal quadrants and cultured for 7 days by treating with the glaucoma factors dexamethasone (Dex) or recombinant transforming growth factor (TGF) β2 or transduced with lentiviral expression vectors containing wild type (WT) and mutant myocilin. Hematoxylin and Eosin (H&E) staining analysis revealed that the TM structural integrity is maintained after 7 days in culture. Increased TUNEL positive TM cells were observed in corneoscleral quadrants treated with glaucoma factors compared to their respective controls. However, these TUNEL positive cells were mainly confined to the scleral region adjacent to the TM. Treatment of corneoscleral quadrants with Dex or TGFβ2 resulted in glaucomatous changes at the TM, which included increased extracellular matrix (ECM) proteins and induction of endoplasmic reticulum (ER) stress. Western blot analysis of the conditioned medium showed an increase in ECM (fibronectin and collagen IV) levels in Dex- or TGFβ2-treated samples compared to control. Lentiviral transduction of quadrants resulted in expression of WT and mutant myocilin in TM tissues. Western blot analysis of conditioned medium revealed decreased secretion of mutant myocilin compared to WT myocilin. Moreover, increased ECM deposition and ER stress induction was observed in the TM of mutant myocilin transduced quadrants. Our findings suggest that the ex-vivo cultured human corneoscleral segment model is cost-effective and can be used as a pre-screening tool to study the effects of glaucoma factors and anti-glaucoma therapeutics on the TM.

Bayesian Method for the Generalized Exponential Model Using Fuzzy Data

This paper focuses on Bayesian inference for the parameters of the generalized exponential model under asymmetric and symmetric loss functions when the observations are described in terms of fuzzy numbers. First, a generalized likelihood function based on fuzzy data is derived. Then, considering general entropy, linear exponential and squared error loss functions, the Bayes estimates of the parameters are obtained. Since Bayes estimates could not be expressed in closed forms, Metropolis–Hasting samplers are used to compute the approximate Bayes estimates. For comparison purposes, the maximum likelihood estimates of the parameters are also computed. The proposed inferences are illustrated using three real-world examples. The numerical simulation results demonstrate the superiority of the Bayesian method over the maximum likelihood procedure.

Vibration analysis of functionally graded graphene oxide-reinforced composite beams using a new Ritz-solution shape function

In this study, a new Ritz-solution shape function, in the form of a combination of polynomials and general exponential functions for various boundary conditions, is constructed from two-dimensional elasticity solutions using an inverse method. In conjunction with an improved third-order shear deformation theory, a reliable and accurate model is developed for the analysis of the mechanical behavior of composite beams. Free and forced vibrations of a functionally graded (FG) polymer nanocomposite beam reinforced with a low content of graphene oxide (GO) and excited by a moving load with a constant velocity are investigated. The weight fraction of the GOs is assumed to vary continuously and smoothly in the thickness direction. The modified Halpin–Tsai micromechanics model is used to evaluate the effective Young’s modulus of the FG GO-reinforced composites. The governing equations of motion are derived using the Lagrange method. The Newmark-β method is adopted to solve the forced vibration problem of a beam subjected to a moving load. A parametric study is conducted to demonstrate the effects of GO distribution patterns, weight fraction, and size on the vibration response of the nanocomposite beam with various classical boundary conditions.

Heat kernel for higher-order differential operators and generalized exponential functions

We consider the heat kernel for higher-derivative and nonlocal operators in $d$-dimensional Euclidean space-time and its asymptotic behavior. As a building block for operators of such type, we consider the heat kernel of the minimal operator - generic power of the Laplacian - and show that it is given by the expression essentially different from the conventional exponential Wentzel-Kramers-Brillouin (WKB) ansatz. Rather it is represented by the generalized exponential function (GEF) directly related to what is known in mathematics as the Fox-Wright $\varPsi$-functions and Fox $H$-functions. The structure of its essential singularity in the proper time parameter is different from that of the usual exponential ansatz, which invalidated previous attempts to directly generalize the Schwinger-DeWitt heat kernel technique to higher-derivative operators. In particular, contrary to the conventional exponential decay of the heat kernel in space, we show the oscillatory behavior of GEF for higher-derivative operators. We give several integral representations for the generalized exponential function, find its asymptotics and semiclassical expansion, which turns out to be essentially different for local operators and nonlocal operators of noninteger order. Finally, we briefly discuss further applications of the GEF technique to generic higher-derivative and pseudodifferential operators in curved space-time, which might be critically important for applications of Horava-Lifshitz and other UV renormalizable quantum gravity models.

Sampling Almost Periodic and Related Functions

We consider certain finite sets of circle-valued functions defined on intervals of real numbers and estimate how large the intervals must be for the values of these functions to be uniformly distributed in an approximate way. This is used to establish some general conditions under which a random construction introduced by Katznelson for the integers yields sets that are dense in the Bohr group. We obtain in this way very sparse sets of real numbers (and of integers) on which two different almost periodic functions cannot agree, which makes them amenable to be used in sampling theorems for these functions. These sets can be made as sparse as to have zero asymptotic density or as to be t-sets, i.e., to be sets that intersect any of their translates in a bounded set. Many of these results are proved not only for almost periodic functions but also for classes of functions generated by more general complex exponential functions, including chirps or polynomial phase functions.