Impact of Default Distance on Financial Warning of Listed Companies

Distance to Default is a measure of credit risk based on stock trading data. According to the result, the default distance can improve the goodness of fit and forecasting ability of the financial early-warning model, but the improvement effect is limited. And with the increasingly fierce market competition, the impact of financial risk on the survival and development of enterprises is also growing. Modern enterprises must fully understand the causes of financial risks, establish and improve risk control mechanisms, prevent and resolve various financial risks in the development of enterprises, To ensure that the development of enterprises toward a reasonable, scientific and healthy direction. Keywords: default distance, financial crisis, financial warnin

Hybrid Tin Based Nanostructures Wrapped with Graphene as Efficient Anode Material for Lithium Ion Batteries

Recently, many developments in the electric & hybrid electric vehicles, and in the electronic devices, have resulted in an increasing demand for high power and high energy density lithium-ion batteries. The current commercial anodes based on graphite cannot meet the demand. Tin sulfide (theoretical specific capacity: 665 mAh/g) has been predicted as a potential anode material. However, its poor conductivity and large volume change during charge and discharge results in large irreversible capacity, leading to poor cycle performance. On the other hand, graphene has emerged as a new material with superior conductivity, good flexibility and extraordinary stability. In this work, we prepared tin sulfides with tuned morphology and composition which is supported by and wrapped with sulphur and nitrogen doped graphene (GSN). These nanostructures were prepared by solvothermal synthesis followed by controlled heat treatment. The as-synthesized material was found to be comprised of stannic sulfide (SnS2) crystals grown and wrapped with doped graphene. Interestingly, the SnS2 crystals are formed as ordered structure in the shape of hexagonal sheets. After that heat treatment the hexagonal nanosheets of SnS2 were transformed to rod-like structure with chemical transformation to stannous sulfide (SnS). In terms of electrochemical performance, both materials have first cycle charge/discharge capacities, which exceed the theoretical values. However, the heat treated material is more durable, which was able to maintain a charge capacity of ~ 870 mAh/g for more than 100 cycles at the rate of 0.1 A/g. At a high current density of 0.5 A/g, it can also keep 1500 cycles with a reversible capacity of ~ 550 mAh/g, which showed the longest cycle life among tin based materials reported in the literature. Inspection of the results reveals that tin sulfide/graphene based nanocomposites with improved energy densities and capacities than commercial graphite can make a significant impact on the development of new batteries for electric vehicles and portable electronics applications. Additionally, incorporating a binder into the electrode structure is vital to achieving practical lithium-ion battery performance, as it is used for improving stability. In this thesis, a new binder is introduced. Polyacrilonitrile(PAN) as a binder with no conductive additives is applied in as-prepared SnS2/G.After low temperature heat treatment which is beyond glass transition temperature, PAN physically rearranges the construction of the electrodes. It is advantageous for volume expansion with plasticity. Synergistic effects between doped graphene and PAN does contribution to significantly enhanced cycling durability. Also, a new mechanism for chemical reaction during charge/discharge is proposed due to the obtained twice higher capacity than the calculation based on traditional principle. In terms of cycling performance and rate capability, SnS2/G/PAN with low temperature heat treatment exhibits excellent results: there is a reversible capacity around 1200 mAh/g after 60 cycles without no obvious decrease in capacity from the initial cycle at the current density 0.1 A/g; after 150 cycles, at a higher current density of 0.25 A/g, the capacity is stable at 1000 mAh/g and the columbic efficiency is still 100%.4 month

Visual Truth and Image Manipulation: Visual Ethical Anomie and Reconstruction of Digital Photography

Digital photography has impacted the visual truth in terms of image operation technology. The paper analyzes the performance of image manipulation in digital photography, and asserts that the operation image’s resolution of visual truth can be described by three aspects: the fact deviation, the reconstruction of the situation, the trust crisis, the filter survival, the second reprint, and the value change. Consequently, there are three visual ethical problems associated with the manipulation of images by technology, the siege of images on people, and distortions of social order caused by the manipulation of images by technology. Thus, it is suggested that visual ethics be reconstructed from three perspectives: reconstructing the dominant role of human beings in the digital era, returning to the original significance of visual images, and constructing multiple visual structures

Rescue of recombinant peste des petits ruminants virus: creation of a GFP-expressing virus and application in rapid virus neutralization test

Peste des petits ruminants virus (PPRV) causes high mortality in goats and sheep and the disease has shown a greatly increased geographic distribution over the last 15 years. It is responsible for serious socioeconomic problems in some of the poorest developing countries. The ability to create recombinant PPRV would provide a useful tool for investigating the biology of the virus and the pathology of disease, as well as for developing new vaccines and diagnostic methods. Here we report the first successful rescue of recombinant PPRV from a full-length cDNA clone of the virus genome. Successful recovery of PPRV was achieved by using a RNA polymerase II promoter to drive transcription of the full-length virus antigenome. We have used this technique to construct a virus expressing a tracer protein (green fluorescent protein, GFP). The recombinant virus replicated as well as the parental virus and could stably express GFP during at least 10 passages. The newly established reverse genetics system for PPRV provides a novel method for constructing a vaccine using PPRV as a vector, and will also prove valuable for fundamental research on the biology of the virus. We found that our recombinant virus allowed more rapid and higher throughput assessment of PPRV neutralization antibody titer via the virus neutralization test (VNT) compared with the traditional method

Modeling and analysis of the transmission dynamics of cystic echinococcosis: Effects of increasing the number of sheep

A transmission dynamics model with the logistic growth of cystic echinococcus in sheep was formulated and analyzed. The basic reproduction number was derived and the results showed that the global dynamical behaviors were determined by its value. The disease-free equilibrium is globally asymptotically stable when the value of the basic reproduction number is less than one; otherwise, there exists a unique endemic equilibrium and it is globally asymptotically stable. Sensitivity analysis and uncertainty analysis of the basic reproduction number were also performed to screen the important factors that influence the spread of cystic echinococcosis. Contour plots of the basic reproduction number versus these important factors are presented, too. The results showed that the higher the deworming rate of dogs, the lower the prevalence of echinococcosis in sheep and dogs. Similarly, the higher the slaughter rate of sheep, the lower the prevalence of echinococcosis in sheep and dogs. It also showed that the spread of echinococcosis has a close relationship with the maximum environmental capacity of sheep, and that they have a remarkable negative correlation. This reminds us that the risk of cystic echinococcosis may be underestimated if we ignore the increasing number of sheep in reality

Recent Advances in Electrospun Sustainable Composites for Biomedical, Environmental, Energy, and Packaging Applications.

Electrospinning has gained constant enthusiasm and wide interest as a novel sustainable material processing technique due to its ease of operation and wide adaptability for fabricating eco-friendly fibers on a nanoscale. In addition, the device working parameters, spinning solution properties, and the environmental factors can have a significant effect on the fibers\u27 morphology during electrospinning. This review summarizes the newly developed principles and influence factors for electrospinning technology in the past five years, including these factors\u27 interactions with the electrospinning mechanism as well as its most recent applications of electrospun natural or sustainable composite materials in biology, environmental protection, energy, and food packaging materials