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We study the CP asymmetries of the rare top-quark decays $t \to c \gamma$ and $t \to cg$ in the aligned two-Higgs-doublet model (A2HDM), which is generically characterized by new sources of CP violation beyond the Standard Model (SM). Specifically, the branching ratios and CP asymmetries of these rare top-quark decays are explicitly formulated, with an emphasis on the origins of weak and strong phases in the A2HDM. Taking into account the most relevant constraints on this model, we evaluate the variations of these observables with respect to the model parameters. It is found that the branching ratios of $t \to c \gamma$ and $t \to cg$ decays can maximally reach up to $1.47\times10^{-10}$ and $4.86\times10^{-9}$ respectively, which are about four and three orders of magnitude higher than the corresponding SM predictions. While the branching ratios are almost independent of the relative phase $\varphi$ between the two alignment parameters $\varsigma_u$ and $\varsigma_d$ within the allowed parameter space, the CP asymmetries are found to be very sensitive to $\varphi$. When the two alignment parameters are complex with a non-zero $\varphi$ varied within the range $[50^\circ,150^\circ]$, the magnitudes of the CP asymmetries can be significantly enhanced relative to both the SM and the real case. In particular, the maximum absolute values of the CP asymmetries can even reach up to $\mathcal{O}(1)$ for these two decay modes, in the range $\varphi \in [70^\circ,100^\circ]$. These interesting observations could be utilized to discriminate the SM and the different scenarios of the A2HDM., Comment: 46 pages, 12 figures, and 3 tables

Uncovering the fundamental neural correlates of biological intelligence, developing mathematical models, and conducting computational simulations are critical for advancing new paradigms in artificial intelligence (AI). In this study, we implemented a comprehensive visual decision-making model that spans from visual input to behavioral output, using a neural dynamics modeling approach. Drawing inspiration from the key components of the dorsal visual pathway in primates, our model not only aligns closely with human behavior but also reflects neural activities in primates, and achieving accuracy comparable to convolutional neural networks (CNNs). Moreover, magnetic resonance imaging (MRI) identified key neuroimaging features such as structural connections and functional connectivity that are associated with performance in perceptual decision-making tasks. A neuroimaging-informed fine-tuning approach was introduced and applied to the model, leading to performance improvements that paralleled the behavioral variations observed among subjects. Compared to classical deep learning models, our model more accurately replicates the behavioral performance of biological intelligence, relying on the structural characteristics of biological neural networks rather than extensive training data, and demonstrating enhanced resilience to perturbation.

We update the Standard Model (SM) predictions for the branching ratios of the rare top-quark decays $t \to cg(g)$, and evaluate the maximum rates that can be reached in the aligned as well as in the four conventional two-Higgs-doublet models (2HDMs) with $\mathcal{Z}_2$ symmetries. Taking into account the relevant constraints on the model parameters resulting from a global fit obtained at the $95.5\%$ confidence level, we find that the branching ratios of $t \to cg$ and $t \to cgg$ decays can reach up to $3.36\times 10^{-9}$ and $2.95\times 10^{-9}$ respectively, being therefore of the same order, in the aligned 2HDM (A2HDM). This is obviously different from the SM case, where the predicted branching ratio of the three-body decay $t \to cgg$ is about two orders of magnitude larger than that of the two-body decay $t \to cg$. On the other hand, compared with the SM predictions, no significant enhancements are observed in the four conventional 2HDMs with $\mathcal{Z}_2$ symmetries for the branching ratios of these two decays. Nevertheless, the predicted branching ratios of $t \to cg$ and $t \to cgg$ decays in the A2HDM are still out of the expected sensitivities of the future high-luminosity Large Hadron Collider and the Future Circular Collider in hadron-hadron mode., Comment: 48 pages, 6 figures, and 4 tables; more references and discussions added, final version published in the journal

With updated experimental data and improved theoretical calculations, several significant deviations are being observed between the Standard Model predictions and the experimental measurements of the branching ratios of $\bar{B}_{(s)}^0\to D_{(s)}^{(*)+} L^-$ decays, where $L$ is a light meson from the set $\{\pi,\rho,K^{(\ast)}\}$. Especially for the two channels $\bar{B}^0\to D^{+}K^-$ and $\bar{B}_{s}^0\to D_{s}^{+}\pi^-$, both of which are free of the weak annihilation contribution, the deviations observed can even reach 4-5$\sigma$. Here we exploit possible new-physics effects in these class-I non-leptonic $B$-meson decays within the framework of QCD factorization. Firstly, we perform a model-independent analysis of the effects from twenty linearly independent four-quark operators that can contribute, either directly or through operator mixing, to the quark-level $b\to c\bar{u} d(s)$ transitions. It is found that, under the combined constraints from the current experimental data, the deviations observed could be well explained at the $1\sigma$ level by the new-physics four-quark operators with $\gamma^{\mu}(1-\gamma_5)\otimes\gamma_{\mu} (1-\gamma_5)$ structure, and also at the $2\sigma$ level by the operators with $(1+\gamma_5)\otimes(1-\gamma_5)$ and $(1+\gamma_5)\otimes(1+\gamma_5)$ structures. However, the new-physics four-quark operators with other Dirac structures fail to provide a consistent interpretation, even at the $2\sigma$ level. Then, as two specific examples of model-dependent considerations, we discuss the case where the new-physics four-quark operators are generated by either a colorless charged gauge boson or a colorless charged scalar, with their masses fixed both at the $1$~TeV. Constraints on the effective coefficients describing the couplings of these mediators to the relevant quarks are obtained by fitting to the current experimental data., Comment: 49 pages, 21 figures, and 7 tables; v2: typos corrected, parts of the plots updated; v3: estimation of annihilation contributions and more discussions added, final version published in JHEP

The susceptibility-based positive contrast MR technique was applied to estimate arbitrary magnetic susceptibility distributions of the metallic devices using a kernel deconvolution algorithm with a regularized L-1 minimization.Previously, the first-order primal-dual (PD) algorithm could provide a faster reconstruction time to solve the L-1 minimization, compared with other methods. Here, we propose to accelerate the PD algorithm of the positive contrast image using the multi-core multi-thread feature of graphics processor units (GPUs). The some experimental results showed that the GPU-based PD algorithm could achieve comparable accuracy of the metallic interventional devices in positive contrast imaging with less computational time. And the GPU-based PD approach was 4~15 times faster than the previous CPU-based scheme., Comment: 4 pages, 6 figures, Accepted at the 42nd Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC 2020)

Extracting the risk neutral density (RND) function from option prices is well defined in principle, but is very sensitive to errors in practice. For risk management, knowledge of the entire RND provides more information for Value-at-Risk (VaR) calculations than implied volatility alone [1]. Typically, RNDs are deduced from option prices by making a distributional assumption, or relying on implied volatility [2]. We present a fully non-parametric method for extracting RNDs from observed option prices. The aim is to obtain a continuous, smooth, monotonic, and convex pricing function that is twice differentiable. Thus, irregularities such as negative probabilities that afflict many existing RND estimation techniques are reduced. Our method employs neural networks to obtain a smoothed pricing function, and a central finite difference approximation to the second derivative to extract the required gradients. This novel technique was successfully applied to a large set of FTSE 100 daily European exercise (ESX) put options data and as an Ansatz to the corresponding set of American exercise (SEI) put options. The results of paired t-tests showed significant differences between RNDs extracted from ESX and SEI option data, reflecting the distorting impact of early exercise possibility for the latter. In particular, the results for skewness and kurtosis suggested different shapes for the RNDs implied by the two types of put options. However, both ESX and SEI data gave an unbiased estimate of the realised FTSE 100 closing prices on the options' expiration date. We confirmed that estimates of volatility from the RNDs of both types of option were biased estimates of the realised volatility at expiration, but less so than the LIFFE tabulated at-the-money implied volatility., Comment: Paper based on Application of Physics in Financial Analysis,APFA5, Conference Presentation, Torino, Italy. 11.5 Pages

The total impedance of a ladder-shape network consisting of inductors and capacitors does not converge to a certain value when the steps of the network increased. In this paper, we analyze this effect in frequency domain. We find that in some band the impedance converge to a limit value while in other band it doesn't. Based on this property in frequency, we propose a filter that exhibits excellent performance both in amplitude and phase response. As a validation of our result, the simulation of this filter was carried out on the EDA software Multisim with respect to a practical circuit.

This paper presents an overview of labour market and sectoral policies in China, focusing on their role in promoting more and better jobs. It analyses the evolution of the labour market over the past 60 years, including the shift in focus from managing rural to urban migration in the framework of the Lewis' (1954) model to productivity-led growth. An issue of concern is the historic inequalities between official urban residents and migrant workers from the countryside due to the hukou - or a model based on household registration - system. The paper also examines the policy-setting and coordination mechanisms in place to ensure that the labour market and sectoral policies respond to immediate needs as well as longer term plans. In essence, current labour market and development policies focus on achieving sustainable and stable growth rates to create adequate productive job opportunities, increasing social protection coverage and strengthening active labour market policies. This is all the more relevant due to the impact of population ageing and underinvestment in human capital. [ABSTRACT FROM AUTHOR]

The article focuses on the design and implementation of fiscal and monetary policy in China with an overview of the trends, the evolution of macroeconomic policies, and the interaction between macroeconomic policies and employment promotion targets.

The article discusses the implementation of macroeconomic policies to promote employment with subtopics including the coordination mechanism for pro-employment macroeconomic policies, the labour market information systems, and the 2002 government response to unemployment.

The article examines the Chinese experience in designing and implementing macroeconomic policies to promote more and better jobs.

The article examines some employment shocks in Chinese history to understand how macroeconomic policies responded to the evolution of employment policies, and how Government departments implemented policies to promote employment and stabilized the labour market.

The article focuses on the changes that happened in pro-employment macroeconomic policies in China since the early 1980s, when the Economic Reforms took place in the countryside and in SOEs, while urban unemployment emerged as a problem for the first time.

Prior to the recent financial crisis, one of the most prominent examples of unconventional monetary stimulus was Japan's "quantitative easing policy"(QEP). Most analysts agree that QEP did not succeed in stimulating aggregate demand sufficiently to overcome persistent deflation. However, it remains unclear whether QEP simply provided little stimulus, or whether its positive effects were overwhelmed by the contractionary forces in Japan's post-bubble economy. In the spirit of Kashyap and Stein (2000) and Hosono (2006), this paper uses bank-level data from 2000 to 2009 to examine the effectiveness in promoting bank lending of a key element of QEP, the Bank of Japan's injections of liquidity into the interbank market. We identify a robust, positive, and statistically significant effect of bank liquidity positions on lending, suggesting that the expansion of reserves associated with QEP likely boosted the flow of credit. However, the overall size of that boost was probably quite small. First, the estimated response of lending to liquidity positions in our regressions is small. Second, much of the effect of the BOJ's reserve injections on bank liquidity was offset as banks reduced their lending to each other. Finally, the effect of liquidity on lending appears to have held only during the initial years of QEP, when the banking system was at its weakest; by 2005, even before QEP was abandoned, the relationship between liquidity and lending had evaporated. [ABSTRACT FROM AUTHOR]

The article discusses the challenges on employment faced by China as its demographic transition entered a new phase which signaled by the deceleration of the working age population growth rate.

The article outlines the evolution of fiscal and monetary policies in China in conjunction with labour market developments, and examines employment trends in the country since the 1978 Economic Reforms along with the reorientation of macroeconomic policies.