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In order to solve the problem of cumbersome external parameter calibration of solid-state lidar and overcome the difficulty in verifying its calibration results, a simple calibration and verification method for solid-state lidar is proposed. This method designs a simple calibration field and markers, uses the markers to complete the angle calibration of the lidar, and completes the distance calibration of the lidar by using the surveying method, so as to reduce the correlation of the external parameters of the angle and the distance, and to ensure the accuracy of the calibration result. Finally, the error of external parameter is obtained through comparison and calculation, and the calibration result of the lidar is verified. The experimental results show that the method proposed is reasonable and effective, and greatly reduces the equipment preparation time and cost required for lidar calibration and verification results, which has a certain application value.

Vitiligo is a common chronic acquired pigmentation disorder characterized by loss of pigmentation. Among various hypotheses proposed for the pathogenesis of vitiligo, oxidative stress-induced immune response that ultimately leads to melanocyte death remains most widely accepted. Oxidative stress which causes elevated levels of reactive oxygen species (ROS) can lead to dysfunction of molecules and organelles, triggering further immune response, and ultimately melanocyte death. In recent years, a variety of cell death modes have been studied, including apoptosis, autophagy and autophagic cell death, ferroptosis, and other novel modes of death, which will be discussed in this review in detail. Oxidative stress is also strongly linked to these modes of death. Under oxidative stress, ROS could induce autophagy by activating the Nrf2 antioxidant pathway of melanocytes. However, persistent stimulation of ROS might eventually lead to excessive activation of Nrf2 antioxidant pathway, which in turn will inactivate autophagy. Moreover, ferroptosis may be triggered by oxidative-related transcriptional production, including ARE, the positive feedback loop related to p62, and the reduced activity and expression of GPX4. Therefore, it is reasonable to infer that these modes of death are involved in the oxidative stress response, and that oxidative stress also acts as an initiator for various modes of death through some complex mechanisms. In this study, we aim to summarize the role of oxidative stress in vitiligo and discuss the corresponding mechanisms of interaction between various modes of cell death and oxidative stress. These findings may provide new ideas for exploring the pathogenesis and potential therapeutic targets of vitiligo.

The relationship among keywords, authors, countries, and publications for the remediation of heavy metal contaminated soils were showed in the knowledge map. Furthermore, the research hotspot evolution path of soil heavy metal remediation, the research status and development trend of related remediation technologies were analyzed. These results visualize the research results through bibliometrics, examine the research in this field from the perspective of the knowledge graph, and provide references for future development.

Since the development of computer science, our lives have become increasingly dependent on software. While we enjoy the benefits and convenience that software programs provide, we cannot ignore issues with software reliability, complexity, and security. Since the introduction of complex networks, people have been using software network to analyze software problems; however, traditional software network models are not currently capable of analyzing software with large scale and complex structures. In this paper, a new software network model is proposed, with which each node in the network can be assigned a set of coordinates that reflect its function-call information and make the disorder of the network graph more orderly. Additionally, characteristics and derivatives of the model are thoroughly examined and analyzed. A case study using the coordinate model combined with bug information is then conducted to analyze five different software programs. The results show that the proposed model can be used to analyze the relationship between nodes or defects distribution and software network parameters, as well as high-risk module excavation through a defect density analysis. Compared to traditional software network models, the model maintains the inner logic relationship of the software systems better, which makes it easier to analyze many aspects of software.

MiRNA is reported as an important biomarker candidate and therapeutic target in a variety of diseases and cancers. However, ultrasensitive, straightforward, isothermal, low-cost and credible methods for the detection of miRNA from clinical specimens still remain challenges. Here, we establish an isothermal, highly sensitive and specific method for miRNA analysis based on a novel ligation-promoted hyperbranched rolling circle amplification (L-HRCA). This strategy exhibits 103-fold sensitivity enhancement compared to T4 ligase-assisted target-primer BRCA. The excellent specificity of L-HRCA allows for discriminating target miRNA from negative miRNAs. This method is applied to analyse the expression level of miR-21 in hepatocellular carcinoma. These results indicated that the L-HRCA strategy will become a promising tool to quantify miRNA in early clinical diagnostics.

Luffa sponge (LS) is a resourceful natural plant fiber with polyporous structure, which can be effectively used for reinforcement of light weight composite materials. However, reduction in the moisture absorption tendency and enhancement in the mechanical properties of LS fiber bundles by chemical modifications are highly desirable in order to utilize LS as reinforcement material. In this study, three chemical treatments including the use of 5% sodium hydroxide and 5% hydrogen peroxide (5%NaOH-5%H2O2), 10% NaOH and 20% acetic acid (10%NaOH-20%CH3COOH), and 18% NaOH and 1.6% carbamide (18%NaOH-1.6%CO(NH2)2) were used to modify the LS fiber bundles. And the effect of the three chemical treatment methods on the micro/nano structures, moisture absorption and mechanical properties of LS fiber bundles was investigated by using scanning electron microscopy (SEM), transmission electron microscopy (TEM), polarized light microscopy (PLM), fourier transform infrared spectroscopy (FTIR), X-ray diffraction analysis, moisture regain (MR) and tensile strength test. The results showed that the treatment with 10%NaOH-20%CH3COOH could significantly improve the mechanical properties of LS fiber bundles, the increase of the tensile strength was 121.3%. However, the treatment with 5%NaOH-5%H2O2 could sharply decrease the mechanical properties of fiber bundles, the reduction of the tensile strength was 75.0%. Furthermore, the treatment with all the three above mentioned chemical combinations could reduce the moisture absorption of LS fiber bundles. The decrease in the moisture regain was found to be 29.0, 16.9, and 12.4%, respectively.

Anti-cancer drug discovery efforts to directly inhibit the signal transducer and activator of transcription 3 (STAT3) have been active for over a decade following the discovery that 70% of cancers exhibit elevated STAT3 activity. The majority of research has focused on attenuating STAT3 activity through preventing homo-dimerization by targeting the SH2 or transcriptional activation domains. Such dimerization inhibitors have not yet reached the market. However, an alternative strategy focussed on preventing STAT3 DNA-binding through targeting the DNA-binding domain (DBD) offers new drug design opportunities. Currently, only EMSA and ELISA-based methods have been implemented with suitable reliability to characterize STAT3 DBD inhibitors. Herein, we present a new orthogonal, fluorescence polarization (FP) assay suitable for high-throughput screening of molecules. This assay, using a STAT3127-688 construct, was developed and optimized to screen molecules that attenuate the STAT3:DNA association with good reliability (Z’ value > 0.6) and a significant contrast (signal-to-noise ratio > 15.0) at equilibrium. The assay system was stable over a 48 hour period. Significantly, the assay is homogeneous and simple to implement for high-throughput screening compared to EMSA and ELISA. Overall, this FP assay offers a new way to identify and characterize novel molecules that inhibit STAT3:DNA association.

Ammonia (NH3) is the primary feedstock for the manufacture of nitric acid and ammonium nitrate in chemical industries. The ammonia combustion is performed using a platinum catalyst at temperatures ranging from 800 to 900 °C in the presence of air to generate nitrogen oxides, principally NO, which is then progressively oxidised to nitric oxide absorber towers. This combustion process is one of the significant contributors to ozone depletion and global warming because it generates considerable amounts of N2O as a by-product. The decomposition of N2O has been widely researched over the last couple of decades. However, the catalytic decomposition of N2O still poses a great challenge. Considerable research has shown that a bed of Co3O4 catalyst above the Pt catalyst may decrease the formation of N2O. However, there is still a dearth of detailed knowledge about the promotion and activity of Pt, which is required to manipulate and then improve the reaction. This study is important because it highlights the combustion of NH3 as a critical step in the production of nitric monoxide (NO), which is subsequently used to produce nitric acid (HNO3) at an industrial scale. Until recently, pure oxygen, rather than air, has been employed as the oxidant in the burner, with steam acting as the thermal ballast; an alternative is the use of air in a process patented by Orica in collaboration with the University of Sydney (aka the JOHANNA Process). Extensive laboratory testing has confirmed the favourable operating characteristics of this process, including the achievement of low selectivity towards N2O. This study explores a methodology for simulating the kinetics of NH3 combustion on platinum surfaces with improved kinetic data and evaluating the conditions in which NH3 is oxidised to NO using O2. The NH3 combustion on Pt surfaces was mathematically simulated using Chemkin-Pro, where atomic chemistry and microkinetics serve as the foundation of the modelling. Atomic chemistry concepts were initially applied to propose elementary reactions in order to build a frame of the NH3 combustion’s reaction system. Microkinetics provided a method that was used to calculate the rates of reactions. Hence, the rates of reactions were obtained from the modelling, which indicated the performance of the reaction and also the catalyst. The kinetics of each reaction step was derived from a number of published resources, with the basic assumption that the initial reaction pathways stem from the parallel reactions between chemisorbed NH3 and oxygen. Density functional theory computations were also carried out when the data was either not available or was uncertain, especially when evaluating the coverage dependence on the thermodynamics of the surface species. The reaction mechanism of NH3 combustion involves several elementary steps that were studied in this work in terms of three different sub-mechanisms; these are presented schematically in Figure 1. Figure 1. Schematic representation of the NH3 reactions over platinum that are analysed in the present work. a) Nitrogen oxide decomposition, b) NH3 decomposition and NH3 combustion The thermodynamic parameters of the adsorbed species on Pt(111) and Pt(211) were obtained by applying the density functional theory at the PBE and HSE06; these parameters were properly presented using the NIST polynomial form, a format that is used in several engineering codes to study the reactivity, mass and heat transfer of catalytic processes. The kinetic parameters of the reaction were obtained via proper computational methods (CI-NEB and Dimer). The effect of the coverage dependence on NH3 conversion and yield of products was analysed in detail. This microkinetic model can account for ammonia decomposition in the absence of oxygen, and the accuracy of its results can be improved by considering lateral interactions in the form of coverage dependence. Some of the important surface species show stability in the temperature regions where previous experimental observations have been determined. We observed large uncertainties in describing the reactions in which O2 is a reactant, specifically in case of NO decomposition and NH3 oxidation. Such large uncertainties could have resulted from the improper treatment of complicated surface species such as O*, N*, and NO*. The calculated enthalpy of formation for each of this species varies by more than 50 kJ mol–1 when PBE and HSE06 are used. Additionally, the enthalpy of formation for almost all intermediates in the reaction changes very rapidly with small changes in the coverage, making the model highly dependent on the dynamic behaviour of the rate of reaction. The NH3 combustion starts at 300 oC, which is only 100 oC above the previous experimental observations. At low temperatures, the selectivity towards N2(g) is the highest, and NO(g) becomes the predominant product above 600 oC, as consistent with experimental observations. In effect, NO decomposition under the industrial conditions of NH3 combustion is very slow, but with a high selectivity towards N2(g).

This study seeks key to analyze the banks' profitability and their determinants in China over the period 2011-2016. Using banks profitability as dependent variable while secured and unsecured borrowing as independent variables, this study analyzes their impact on banks. By applying correlation and linear regression technique the empirical findings show a significant positive relationship with profitability of banks. Based on findings in this study, it is recommended that Chinese Banks should focus to increase their loan administration and credit capacity in order to get more benefit.

Identifying the most important classes in a software system is crucial for engineers to understand or maintain an unfamiliar system. Complex network theory provides a new way to study the characteristics of large-scale software. Unfortunately, most current studies consider only one or a limited number of factors affecting software structure, rendering inaccurate the results of mining the key classes of software. Thus, we propose an approach using various complex network metrics to automatically identify key classes from global and local aspects. From the global aspect, the location of a class and its ability to control the information flow of software are mainly considered. From local aspects, we focus on the interactions of classes with their neighbors, as well as the complexity of the class itself. Experiments are performed on two java open-source projects. Results show that this approach can accurately identify key classes compared with existing literature.

A convenient synthesis of 1,3-di- and 1,2,3-tri-substituted indolizines involving the multicomponent reaction of pyridinium salt (or quinolinium salt), olefine acid, and 1,2-dichloroethane has been achieved. The process proceeds smoothly in moderate to high yields.

In the field of behavioral finance mood, emotions and other different effecting factors have been investigated regarding stock market return. Weather is one of the most important and vital factor that has been analyzed. In this empirical study the two different stock exchanges (Eastern Asian and South Asian) are compared with respect to the weather variable temperature. The analysis and investigation has been made by utilizing the six years record of both stock exchange (China, Pakistan) indexes (SSE-180, KSE 100). The Autoregressive (AR) Conditional Heteroscedasticity (GARCH) technique has been utilized for analysis. It has been found that temperature is the most affecting factor that has negative effect on both stock exchanges. The effect of temperature on both stock exchanges has been compared and found that Eastern Asian Country have more effect as compared South Asian country. The results are given in detail by using Eviews Package.

The infiltration kinetics of liquid metal into a fibrous preform was analyzed theoretically on the basis of Darcy's law and the assumptions that the porous preform can be treated as “bundles of capillaries” and that the liquid flow penetrating the preform is laminar. Experiments in infiltration kinetics were carried out with respect to an Al–1.5 Mg aluminium alloy/alumina short fiber preform system. It was revealed that an incubation time is required to activate infiltration, that there is a parabolic dependence of the infiltrated depth on the infiltration time for an infiltration process under constant external pressure, and that the infiltration rate can be well predicted by the equation derived by the theoretical model proposed in the present paper. Both the incubation time and the infiltration rate are influenced significantly by the applied pressure.

This paper is analyzing the unemployment duration difference of individuals under different high school programs in Sweden. The cause of the analysis has from stemmed from different fields of study and its effect on employment positions in the labour market. We see education as a factor of key importance. In addition to research on an education level, the type of study also plays an important role. Therefore, how different school programs affect unemployment duration becomes the central question we try to answer in this paper. To pursue a clear analysis structure, we start with previous studies on an education level and show the author’s interest into the research of the field of study’s effect on unemployment. Job search theory is applied to do analysis on the data. Then, an empirical analysis of unemployment duration is conducted. This is done through linear regression using the least-squares method. Finally, conclusions are made as well as some policy implications and ideas for further research.

A comprehensive survey and in-depth analysis related to reflective cracking have been conducted at five expressways in Jiangsu province, China. This paper presents analysis results with respect to the main influencing factors of pavement transverse cracking and reflective cracking, revealing the developing mechanism of pavement transverse cracking and reflective cracking. Furthermore, influencing factors and their effects on reflective cracking of semi-rigid base are also proposed in this paper. Several recommendations are presented to effectively prevent reflective cracks.

It is well known that the stock market, viewed as a complex, open, and nonlinear dynamical system, is affected simultaneously by many factors, such as international environment, government policies, political situation, economic situation, the public psychology over some events, some rumors, and so on, which intrinsically influence each other and make the relationships very complicated. Some of these have long influences on the market, while others have short influences on it. The arguments of synergetics, cooperation and competition among the state variables led to the case in which the system is governed by only a few slow variables. But we have no way to exactly know which and how the states govern the evolution of the system. All that we have available is the observable generated by the states, time series (index price series) from the system, which carries the information on the system of interest. How can we understand the dynamics of the system from the observable, say, the evolution of the system? We reconstruct the attractor of stock market from its stock index series with respect to delay embedding theorem (F. Takens, 1981). The attractor can then be fully unfolded in our reconstructed phase space without trajectory intersections, getting a diffeomorphic copy of the original attractor. It is suffice to say that the evolution in reconstructed phase space faithfully images, on the whole, the evolution in the original phase space, consequently laying a theoretical foundation for predicting stock index series.