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Seasonality is typical in the stock market, and a specific month reflects investors' mood. During the same calendar months, the cross-sectional stocks' better or worse performance relative to other stocks in specific months signifies investor mood seasonality. Using the Chinese A-share market's monthly data from 1999 to 2019, we find that the mood seasonality effect is significant. Besides, there is a positive relationship between mood beta and stock return during a congruent mood period. Moreover, the investment strategy can obtain a significantly positive average return based on February's mood beta.

At present, the deep neural network model is commonly used to detect the vehicle in the video, and the detection accuracy is relatively high. However, the neural network model requires high computing performance and high demand for network transmission bandwidth. In many cases, the edge computing device used is of small computing power, so the neural network model is not applicable. However, background subtraction algorithm is easy to realize because of its low requirement on hardware calculation force and fast and accurate detection speed. Using SORT algorithm to track with accurate detection results can improve the speed again and reduce the consumption of computing resources. Therefore, this paper proposes an algorithm that uses the background subtraction algorithm to detect the vehicles in the video, and then uses the SORT algorithm to track the detected vehicles. The vehicle counter will automatically count when the vehicle in the video passes the traffic flow counting line. The accuracy of traffic flow counting results in this paper is 88%, which proves the feasibility and effectiveness of vehicle detection counting method based on background subtraction algorithm and SORT.

The tracking-by-detection strategy is the backbone of many methods for tracking living cells in time-lapse microscopy. An object detector is first applied to the input images, and the resulting detection candidates are then linked by a data association module. The performance of such methods strongly depends on the quality of the detector because detection errors propagate to the linking step. To tackle this issue, we propose a joint model for segmentation, detection and tracking. The model is defined implicitly as limiting distribution of a Markov chain Monte Carlo algorithm and contains a temporal feedback, which allows to dynamically alter detector parameters using hints given by neighboring frames and, in this way, correct detection errors. The proposed method can integrate any detector and is therefore not restricted to a specific domain. The parameters of the model are learned using an objective based on empirical risk minimization. We use our method to conduct large-scale experiments for confluent cultures of endothelial cells and evaluate its performance in the ISBI Cell Tracking Challenge, where it consistently scored among the best three methods.

This paper investigates the relationship between idiosyncratic volatility and the risk of a stock price crash in China. Using a large sample of Chinese listed firms from 2007 to 2018, the evidence shows that stock price crash risk is significantly positively associated with idiosyncratic volatility. Moreover, firms with a higher level of idiosyncratic volatility are more likely to experience a crash in stock price. The results are robust to alternative measures of idiosyncratic volatility and stock price crash risk and the findings advance our understanding about the role of short-selling constraints in managing the risk of a stock price crash.

This paper presents the study of unsteady nanofluids flow and heat transfer past a wedge with second order velocity slip and temperature jump. The model is modified by considering the existence of a nanolayer together with the effects of thermophoresis and Brownian motion. The fundamental equations were transformed into ordinary differential equations by a new set of similarity transformations and solved by using the homotopy analysis method (HAM). We determined that the error reached 10-6 and the effectiveness of HAM was attained. The influence of second-order slip on the fluid skin-friction coefficient was analyzed and we determined that the Nusselt number decreases and skin friction coefficient rises with an increase in the thickness of the nanolayer.

Endothelial cells of the vascular system are dynamic cells whose molecular adaptability is decisive for the adjustment of homeostasis and organ perfusion. Advanced microscopic techniques, automation processing, and image analysis software was shown to improve the understanding of vascular biology. In this work, we describe advanced methods that allow investigating the dynamics of endothelial cell contacts. The development of viral vectors has contributed significantly to the genetic manipulation of endothelial cells. We used the Gibson assembly as a quick and cheap cloning system for introducing sequences into the lentiviral-based pFUGW vector. Furthermore, classical fluorescence tags such as mCherry and EGFP were compared with self-labeling tags such as Halo and SNAP for their suitability to study junction dynamics in cultured endothelium, and found the self-labeling tags as useful tools. Using such combinations, we found maintained cell junction integrity during shear stress-induced junction remodeling using VE-cadherin-EGFP. Remodeling was accompanied by VE-cadherin plaque formation, indicating that this process is mediated by the for­mation of the actin-driven junction-associated intermittent lamellipodia, JAIL. The combined methods including the Gibson assembly, lentiviral mediated gene transfer, spinning disk-based live cell imaging, and software for quantification allow analyses of the endothelial cell junction dynamics under static and under shear stress conditions.

VEGFR-2/Notch signalling regulates angiogenesis in part by driving the remodelling of endothelial cell junctions and by inducing cell migration. Here, we show that VEGF-induced polarized cell elongation increases cell perimeter and decreases the relative VE-cadherin concentration at junctions, triggering polarized formation of actin-driven junction-associated intermittent lamellipodia (JAIL) under control of the WASP/WAVE/ARP2/3 complex. JAIL allow formation of new VE-cadherin adhesion sites that are critical for cell migration and monolayer integrity. Whereas at the leading edge of the cell, large JAIL drive cell migration with supportive contraction, lateral junctions show small JAIL that allow relative cell movement. VEGFR-2 activation initiates cell elongation through dephosphorylation of junctional myosin light chain II, which leads to a local loss of tension to induce JAIL-mediated junctional remodelling. These events require both microtubules and polarized Rac activity. Together, we propose a model where polarized JAIL formation drives directed cell migration and junctional remodelling during sprouting angiogenesis., The formation of new blood vessels requires both polarized cell migration and coordinated control of endothelial cell contacts. Here, Cao and colleagues describe at the sub-cellular level the cytoskeletal and cell junction dynamics regulating these processes upon VEGF-induced cell elongation.

A non-precious metal catalyst Ni/NiO is developed for the efficient hydrogenation of levulinic acid to γ-valerolactone under mild conditions. Treating nickel oxide in hydrogen at controlled temperature of 473–573 K results in its partial reduction to metallic nickel and the formation of Ni/NiO heterojunctions, as indicated by the characterization results from in situ XRD, XPS and TEM. The as-prepared Ni/NiO catalyst exhibits remarkable activity in levulinic acid hydrogenation with a high mass activity of 14.1 mmol/h/g at 393 K, being over 18 times higher than NiO and 10 times higher than metallic Ni. Besides, Ni/NiO shows very good stability and recyclability during the reaction, making it a promising catalyst for practical levulinic acid hydrogenation. The formation of Ni/NiO heterojunctions is crucial for the remarkable activity of Ni/NiO composite catalyst and a cooperative Langmuir-Hinshelwood mechanism is proposed for levulinic acid hydrogenation on the basis of kinetic analysis and theoretical calculations. The concept of cooperative catalysis on metal/oxide heterojunctions can be expanded to other hydrogenation reactions.

Building on the increased interest in the volatility spillover effects between Chinese stock market and commodity markets, this paper investigates the dynamic volatility spillovers of Chinese stock market and Chinese commodity markets based on the volatility spillover index under the framework of TVP-VAR. The result shows that there is a highly dependent relationship between the stock market and commodity markets. On average, the Chinese stock market is the net recipient of spillover, non-ferrous metals and chemical industry have a very obvious spillover impact on the stock market. The degree of total volatility spillover is different in different periods. After major crisis events, the volatility correlation between markets increases. Since the outbreak of COVID-19, the spillover effect of the stock market on the commodity market has been significantly enhanced. Then optimal portfolio weights and hedge ratios are calculated for portfolio diversification and risk management. The result shows that the ability of most commodities to hedge against risks is significantly reduced when the crisis occurs; NMFI (precious metals) and CRFI (grain) still have good hedging ability after the crisis, but the effectiveness of hedging risk is relatively low. Besides, the combination of CRFI and SHCI (the Shanghai composite index) is the most effective for risk reduction.

Estimating the influence of dust aerosol on clouds, especially deep convective clouds which is closely related to heavy precipitation, still has large uncertainties due to the lack of adequate direct measurements. In this study, a typical dust storm along with thunderstorm (referred to dust-rain storm), occurred in Northwest India on May 2, 2018, was selected to explore the possible effects of dust aerosol on deep convective cloud by combining a series of satellite retrievals and reanalysis data. Results showed that dust aerosol and moisture were carried to Northwest India by southwesterly wind at 700 hPa and easterly wind along south foothill of Himalayas at 850 hPa, respectively, and then were lifted to upper level of the cloud by robust updraft induced by the deep convection and secondary circulation driven by the upper-level westerly jet. The injection of dust is likely to transfer supercooled water cloud into ice cloud as effective ice nuclei, hence increasing the cloud ice water path and cloud optical depth but decreasing ice particle radius in the cloud. The latent heat released by this phase-change process would enhance the deep convection and further cause heavy rainfall in northern India by drawing moisture from surrounding region. Although we cannot eliminate the effect of large-scale dynamics, this study highlighted the role of dust aerosol in invigorating the deep convective clouds as ice nuclei, providing observation evidence for the investigation of aerosol-cloud-precipitation interaction.

When planning a residential community, an important factor–occupant behavior–is often omitted. Previous research suggested that the age of occupants may significantly affect the dwelling time and use of air conditioners, thus should be considered during low carbon oriented residential community planning. In this study, an energy related occupant behavior survey recently conducted in Qingdao city is presented. Through this survey, the thermal preference, dwelling time, and air conditioners usage behavior of three different family structures (young couple family, old couple family, and couple with parents family) are analyzed. These information, together with urban planning parameters (floor area ratio, building coverage ratio, aspect ratio, etc.) are then fed into energy simulation models, to investigate the role of occupant behavior in low carbon oriented residential community planning. The results show that the energy demand of old couple family is more affected by community planning. Aspect ratio is more important than height in terms of space cooling and heating demand. The optimal aspect ratio strongly depends on the type of occupants and HVAC system. In general, aged occupants need more heating energy, thus are better located in buildings with lower aspect ratio. Communities with district heating system and decentralized cooling system need lower aspect ratio than that with other types of HVAC systems. The results have important implications to low carbon oriented residential community planning.

Purpose Recently, a new marker protein for microglial cells in the brain was postulated, transmembrane protein 119 (TMEM119), raising the hope for a new opportunity to reliably and unambiguously detect microglial cells in histologic sections. It was of interest whether TMEM119 also was a reliable microglial marker in the retina. Methods Anti-TMEM119 antibodies of two providers were used to label microglia in the murine retina, and labeling properties were compared to those of antibodies against Iba1 and CD11b. As an example of a pathologic situation, labeling for TMEM119 was also performed in eyes treated by an argon laser as an experimental model for choroidal neovascularization. Results TMEM119 immunoreactivity (IR) was found on microglial cells in the naive retina. However, specificity and sensitivity of TMEM119 IR varied clearly depending on the source of the antibody, age of the mouse, and location of retinal microglia. After laser treatment, however, microglial cells lost their IR for TMEM119 at the site of the laser spot. Moreover, other cells became positive for TMEM119; for example, Muller cells. Conclusions TMEM119 is a useful marker for the microglia in the brain. However, retinal microglia shows variable IR for TMEM119, and the microglia is not the only cell showing TMEM IR. Therefore, TMEM119 appears not to be applicable as a general marker for the retinal microglia in pathologic situations. Translational Relevance Reliable detection and quantification of microglial cells is of high importance to study disease mechanisms and effects of therapeutic approaches in the retina.

Junction dynamics of endothelial cells are based on the integration of signal transduction, cytoskeletal remodeling and contraction, which are necessary for the formation and maintenance of monolayer integrity, but also enable repair and regeneration. The VE-cadherin–catenin complex forms the molecular basis of the adherence junctions and cooperates closely with actin filaments. Several groups have recently described small actin-driven protrusions at the cell junctions that are controlled by the Arp2/3 complex, contributing to cell junction regulation. We identified these protrusions as the driving force for VE-cadherin dynamics, as they directly induce new VE-cadherin-mediated adhesion sites, and have accordingly referred to these structures as junction-associated intermittent lamellipodia (JAIL). JAIL extend over only a few microns and thus provide the basis for a subcellular regulation of adhesion. The local (subcellular) VE-cadherin concentration and JAIL formation are directly interdependent, which enables autoregulation. Therefore, this mechanism can contribute a subcellularly regulated adaptation of cell contact dynamics, and is therefore of great importance for monolayer integrity and relative cell migration during wound healing and angiogenesis, as well as for inflammatory responses. In this Review, we discuss the mechanisms and functions underlying these actin-driven protrusions and consider their contribution to the dynamic regulation of endothelial cell junctions.

Most of the energy leaves our bodies in the form of heat simply due to existing temperature gradients in the environment. An average human body at rest emits about 350,000 J of energy per hour, which is roughly equivalent to the energy given off by a 100-Watts incandescent light bulb [1]. As a matter of fact, the conversion of human-body-heat into electrical energy using a solid-state thermoelectric generator (TEG) sparks interest in creating wearable self-powered mobile electronics and sensors [2]. This paper develops a prototype to investigate the performance of a human-body-heat-powered mobile fan using a commercial TEG and a heat-sink structure [3]. The heat-sink is attached to the cold-side of the TEG, with a 20mm x 7mm DC motor centered by the pin fins. As body-heat from the wrist is being applied to the hot-side of the TEG via thermal conduction, a voltage is generated across the terminal of the TEG to power the DC motor, whereas the operating DC motor produces further cooling to the heat-sink through forced convection. The proposed model is calculated analytically by solving governing equations of heat transfer, numerically via ANSYS Thermo-Electric simulation, and experimentally by testing the customized model. The temperature and voltage distributions in the TEG are analyzed, and the effects of the material properties, sizing of the TEG and heat-sink structures, and thermal contact resistance at the interface between TEG and human-skin are discussed. The results obtained in this research can be utilized for optimal structural designs of wearable TEGs and for material selection to enhance the power generation for body-heat-powered mobile devices.

We design and fabricate terahertz split ring resonators with nanogaps for extremely high field enhancement factor of >100000 when the splitting gap is sub-10 nm, and the experimental results agree very with the simulated results.

Intercellular junctions of the vascular endothelium are dynamic structures that display a high degree of plasticity, which is required to contribute to their regulation of many physiological and pathological processes including monolayer integrity, barrier function, wound healing and angiogenesis. Vascular endothelial cadherin (VE-cadherin) is connected via catenins to the actin cytoskeleton, both of which are key structures in endothelial junction regulation, and thus are the focus of much investigation. Fluorescence-based live cell imaging is the method of choice to study dynamic remodeling in living cells. Although these methods have been successfully applied to many cell types, investigations of endothelial junction dynamics were for a long time limited as they are largely resistant to transfection using many classical protocols. Application of virus-based gene transduction techniques, together with advanced microscopy, now allows both sufficient expression of fluorescence tagged junction-localized proteins in the endothelium and time-lapse recording over long periods. Using highly spatiotemporally resolved fluorescence microscopy it turned out that endothelial junctions display extensive junction heterogeneity at the subcellular level; a fact that largely limits automated quantification by available software. Recent work describes open software tools to quantitatively analyze large amounts of fluorescence-based image data in either single or confluent epithelial and endothelial cells. Based on quantitative VE-cadherin and actin dynamics novel key players, mechanisms and concepts have been suggested that control endothelial junction dynamics. Here we aim to summarize the recent developments in the field.