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Grain boundary engineering has been widely applied to improve grain boundary-related properties such as intergranular corrosion, radiation damage and cracking in face-centered cubic metals with low to medium stacking fault energy. However, only a few investigations have been conducted to reduce the susceptibility to intergranular hydrogen embrittlement. Hydrogen embrittlement has severe effects on applications of engineering materials. In this study, grain boundary engineering was successfully applied to enhance the hydrogen embrittlement resistance of 304 austenitic stainless steel. Optimum grain boundary character distribution was acquired through thermomechanical treatments of 7% cold-rolling reduction and subsequent annealing at 1 0758C for 7 min, which reduced the two hydrogen embrittlement sensitivity indices, Id from 13.5 to 5.2 and Iw from 7.2 to 1.6. The effect of grain boundary character distribution comes from two aspects. On the one hand, special boundaries have some positive effects on the alleviation of hydrogen charging. Under the same charging condition, the charged hydrogen concentration decreases with increasing fraction of low-R CSL boundaries. On the other hand, special boundaries, especially R3 boundaries, could help to hinder the initiation and propagation of hydrogen- induced cracks. Therefore, the resistance of hydrogen embrittlement increases with increasing fraction of low-R CSL boundaries.

Although thermomechanical processing has been widely used in grain boundary engineering, the relationship between thermomechanical parameters and grain boundary character distribution is still not well understood. In the present study, electron backscatter diffraction was used to study the grain boundary character distribution in pure copper after lowstrain thermomechanical treatments. It was found that the low-R coincidence site lattice frequency and grain size decreases in the following sequence, 10% compression > 15% compression > 5% compression, except for 700 0C. During thermomechanical treatments of copper, strain-induced grain boundary migration and grain growth may occur during annealing of 5% compressed copper, and recrystallization dominates during annealing of 15% compressed copper, while the annealing mechanism of 10% compressed copper changes from strain-induced grain boundary migration and grain growth to recrystallization when the annealing temperature exceeds 600 0C. The results indicated that during single-step low-strain thermomechanical treatments, straininduced grain boundary migration and grain growth would gradually change to recrystallization with the increase of pre-deformation level and annealing temperature. Among the three mechanisms, strain-induced grain boundary migration seems to be more effective than recrystallization and grain growth in the optimization of grain boundary character distribution, and it is suggested that this is due to the high boundary migration rate of strain-induced grain boundary migration.

Non-alcoholic fatty liver disease (NAFLD) is becoming the most predominant burden of chronic liver disease worldwide. Non-alcoholic steatohepatitis (NASH), the progressive form of NAFLD, can develop into cirrhosis and hepatocellular cancer. Unfortunately, current options for therapeutic treatment of NASH are very limited. Among multiple pathways in NASH, farnesoid X receptor (FXR), a nuclear bile acid receptor, is well-recognized as an important effective target. Here we report the synthesis and characterization of compound HEC96719 a novel tricyclic FXR agonist based on a prior high-affinity nonsteroidal molecule GW4064. HEC96719 exhibits excellent potency superior to GW4064 and obeticholic acid in in vitro and in vivo assays of FXR activation. It also shows higher FXR selectivity and more favorable tissue distribution dominantly in liver and intestine. Preclinical data on pharmacokinetic properties, efficacy, and safety profiles overall indicate that HEC96719 is a promising drug candidate for NASH treatment.

Idiopathic pulmonary fibrosis (IPF) is a chronic progressive lung disease with a typical survival time between three to five years. Two drugs, pirfenidone and nintedanib have been approved for the treatment of IPF, but they have limited efficacy. Thus, the development of new drugs to treat IPF is an urgent medical need. In this paper we report the discovery of a series of orally active pyrimidin-4(3H)-one analogs which exhibit potent activity in in vitro assays. Among them, HEC-866 showed promising efficacy in rat IPF models. Since HEC-866 also had good oral bioavailability, a long half-life and favorable long-term safety profiles, it was selected for further clinical evaluation.

This paper reviews the historical trends of the distribution of income and wealth in the United States. It also discusses the literature on whether imposing wealth tax suggested by Senator Warren and Sanders will improve the inequalities. The paper researches the tax policy regarding the Wealth taxes on ultra-wealthy households, the policy that has been proposed by Democratic presidential candidates to fight against inequality and raise extra revenue in the long term.

The purpose of this paper is to empirically analyze the United States’ trade patterns in goods based on the gravity model and evaluate whether trade agreements such as the North American Free Trade Agreement (NAFTA) are in the best interest of the US economy. The Gravity Model, US-Canada empirical trade data, and US-Mexico data supports the theoretical model. While it’s hard to incorporate all the factors into the assumptions in estimating the trade among NAFTA, the econometric model proved that there is some positive impact in terms of increasing the overall goods trading volume as a result of the United States implementing NAFTA in the early 1990s. However, it is hard to evaluate the overall benefits due to the limitations of the model such as small sample sizes and few independent variables. The Ricardian model and the Heckscher-Ohlin model are used to provide theoretical grounds.

The purpose of this paper is to present statistical analysis of the Environmental Kuznets Curve (EKC) theory, the hypothesized relationship between different environmental indicators, by analyzing empirical studies from existing literature. This paper describes the critical history and theory of the EKC, its theoretical foundations, and possible deviations with the focus on utilizing the Simultaneous Equation Model (SEM). The Kuznets Curve proposes that as an economy develops, the inequality will increase as the income per capita increases; however, it will then decrease and display an inverted U-shaped pattern. The goal is to assess if EKC aligns with the imperial analysis in the case of the Chinese economy as China has experienced the fastest economic growth over the past decade.

The interaction between interfacial dislocations and γ/γ′ interface is critical to the high temperature creep properties of single crystal superalloys. However, only a few studies have paid attenti...

Microstructural stability is of great importance for the application of rhenium-containing nickel-based single-crystal superalloys. The microstructures of single-crystal superalloy DD6, especially the precipitation characteristics before and after thermal exposure, were characterized using scanning electron microscopy, transmission electron microscopy, and related techniques. Acicular M 6C carbides, rod-like M 6C carbides, and granular μ phases have been observed in the aged alloys, and the orientation relationships of these precipitates have been identified. During the early stage of M 6C precipitation, the carbide maintains a cube-on-cube orientation relationship with the matrix, whereas further growth of the M 6C carbides leads to a twin-related orientation relationship. For the granular μ phases containing a high concentration of Re, no special relationship has been observed. The results of the study will be beneficial for the understanding and improvement of nickel-based single-crystal superalloys.

Two-step sintering method has been used to prepare complex perovskite Ba(Zn1/3Nb2/3)O3 ceramics, aiming to inhibit the “order-disorder” transition before dense. Compared with conventional sintering process, this technique has lowered the sintering temperature less than the transition temperature. X-ray diffraction analysis and transmission electron microscopy studies reveal that Ba(Zn1/3Nb2/3)O3 ceramics prepared by two-step sintering possess a high degree of cation ordering. Effects of each sintering parameter on the microstructure and microwave dielectric properties have been investigated systematically. It is found that Q×f could be significantly improved by controlling T1, temperature in the first sintering stage, as well as t2, holding time in the second stage, attributed to the promotion of cation ordering degree and growth of ordering domain structure separately. Compared with conventional sintering, the ceramics with the grain size of 1.1 μm prepared by two-step sintering showed optimal dielectric properties of Q×f ∼75100 GHz (enhanced by 15%).

It is known that poverty and HIV rates are highly correlated so that sample estimations of applying poverty to inspect HIV is subjective and biased. Thus, the aim of this paper is to investigate the impact of different factors collectively on the rates of HIV across 37 countries and regions around the world. Due to the limitation of finding completely accurate and continuous data for one country chronologically, the data for each individual country is from the year 2000. This paper provides an empirical evaluation of Education, Healthcare is and Unemployment rates and examines whether a correlation is presented among the three independent factors. Data shows a statistically significant relationship between Health care and Unemployment and the HIV-Infected rate. It is surprising that the Education factor had the inverse impact than anticipated and the reason is noteworthy and thought-provoking, suggesting the potential faults in HIV-Education programs. The statistical value of the Education factor presents the failure of allocating educating resources and positively educating people about HIV.

In a pandemic like the 1854 Broad Street Cholera outbreak in London or COVID-19 today, it is difficult for whistleblowers to weigh between social responsibility and loyalty. A whistleblower is a person who chooses to disclose sensitive information impacting the public’s health and welfare. John Snow, the father of modern epidemiology, was the scientist who identified the modern germ theory, contradicting the scientific theory held by the majority of people at the time in 1850s, and this theorem was not accepted by the scientific community until later. Compared to the difficulty Snow faced as a ‘whistleblower’ in the outbreak of cholera in London, it is even harder for whistleblowers today to be recognized by the public. The current issue whistleblowers face is that their information is being suppressed. Should people tell the truth or obey orders when these two are in conflict? This question speaks to the debate over the ethics of fairness and loyalty that Steven Minz explores in “Is Whistle-blowing an Ethical Act Practice”. The extent to which this type of loyalty applies becomes less obvious when encountering abnormal situations, such as a pandemic. In the current context of the COVID-19 global pandemic, two well-known cases of whistleblowers have emerged. Given the outcomes of these individual cases, evaluating the ethical implications of social responsibility and loyalty of a person who is forced to make such decisions, like Wenliang Li and Brett Crozier, may help to evaluate the necessity of whistleblowers in the future.

Stochastic Calculus deals with the rate of change of functions with respect to the randomness. It has been applied in the field of financial mathematics. When we look at the graph of stock prices, there are many irregular price fluctuations. The main tool for modeling the small fluctuations is the Brownian motion. This paper will mainly introduce the concept of Brownian motion, the concept of random walks, and the main flavors of stochastic calculus, Ito calculus. I will also discuss various applications, especially in the finance area.

L a 2 M o O 6 : Y b 3 + , E r 3 + upconversion (UC) micro-crystals with a tetragonal structure were fabricated through a modified sol–gel method. The samples are found to be spherical in shape with a diameter of about 300 nm. Upon excitation of 980 nm light, the UC emission spectra of the phosphors exhibit green and red bands corresponding to the characteristic transitions of E r 3 + ions. As Y b 3 + concentration rises, the green emission intensity increases and reaches the maximum at 2.0% Y b 3 + content, while the ratio of green/red emission intensities ( I G / I R ) declines monotonically. Temperature sensing capability was studied employing the fluorescent intensity ratio technique from the thermally coupled levels 2 H 11 / 2 and 4 S 3 / 2 of E r 3 + in temperature range of 293 ∼ 533 K. It is interesting to find that Y b 3 + concentration has influence on the absolute sensitivity S A , while the relative sensitivity S R is almost independent of Y b 3 + content. Furthermore, excellent thermal stability and high temperature sensitivity is also demonstrated in the 2.0% Y b 3 + -doped sample with the obtained maximum S A and S R as high as 0.008 K − 1 and 1.093 % K − 1 , respectively. The experimental results indicate that Y b 3 + / E r 3 + co-doped L a 2 M o O 6 phosphors can be excellent candidates for temperature sensing applications.

By controlling oxygen pressure, ferric oxide with different oxidation state can be formed by pulsed laser deposition (PLD). SEM was used to study the surface topography, XPS to study the oxygen ratio, and SQUID to study the magnetic property of these obtained thin films. Thin films grew under low oxygen pressure maintain good magnetic property, and magnetic property can be adjustable with increasing oxygen pressure. This work showed a clear relationship between process (oxygen pressure), structure (stoichiometry), and (magnetic) property, which demonstrated the modified PLD can offer a way to expedite the experiment procedure and obtain materials structure-property relationship.

This paper will explore concepts of the Markov Chain and demonstrate its applications in probability prediction area and financial trend analysis. The historical background and the properties of the Markov’s chain are analyzed.

We installed the Shining package to RStudio and carefully learned its functions. However, as the R Shiny package mainly focused on the interactive nature of histogram with different distribution types, we are interested to investigate about the visualization of mean.

My goal is to critically examine the philosophical literature on vegetarianism, due to the topic’s correlation and relevance to my own thesis, by comparing and contrasting two of the major approaches in normative ethics, which are consequentialism and virtue ethics. Animal testing refers to any scientific experiments operated on non-human animals that can cause pain, suffering, distress, or lasting pain. Research shows that it has been estimated that 100 million vertebrates are annually experimented (Taylor, Gordon and Langley, 2008). Paying close attention to animal testing matters because the animal rights problem has been debated and a variety of products—such as pharmaceuticals, cosmetics, and food—rely heavily on animal testing. Consumers play a key role in the market and thus, it is worthy to approach this problem philosophically by examining normative ethics.

The effect of MgO content on the microstructure and microwave dielectric properties of MgO-doped 0.84CaTiO3–0.16Sm0.9Nd0.1AlO3 ceramics, prepared by solid-state reaction method, was investigated. The permittivity, ϵr, of the MgO-doped 0.84CaTiO3–0.16Sm0.9Nd0.1AlO3 ceramics was about 65, and it decreased slightly with increasing MgO content. And the temperature coefficient of resonant frequency, τf was tuned from +53.3 ppm/°C to +26.4 ppm/°C as the MgO addition increasing. In addition, it is found that a small amount of MgO could effectively promote the uniformity of the grain morphology, which is beneficial for the improvement of Q × f value. However, grain growth was restrained, and secondary phase MgAl2O4 was observed as MgO content increasing to 0.8 wt%; thus, Q × f value deteriorated seriously. Considering these three parameters of the microwave dielectric properties, the 0.4 wt% MgO-doped 0.84CaTiO3–0.16Sm0.9Nd0.1AlO3 ceramics exhibited the best performance of ϵr = 64.21, Q × f = 30867 GHz, and τf = 26.4 ppm/°C sintered at 1375 °C for 3 h.

The formation of core–shell structure plays a very important role in temperature stable BaTiO3-based dielectric ceramic for multilayer ceramic capacitors applications. In this work, the rare earth Dy modified BaTiO3 dielectric ceramics have been prepared by chemical coating method, which possess high dielectric constant and high insulation resistivity, satisfying the EIA X7R specification. The existence of core–shell structure was proven by transmission electron microscopy observation and energy dispersive spectroscopy analysis. Experimental results show that the sintering temperature has a strong effect on the core–shell structure evolution in Dy-doped BaTiO3 ceramics. Thus, selecting an appropriate sintering temperature is conducive for improving the temperature stability for multilayer ceramic capacitors applications. Furthermore, impedance analysis and the highly accelerated lifetime test show that the core–shell structure evolution has a closely relationship with the reliability accompanied by the increasing of sintering temperatures.