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This study presents a mathematical modeling and numerical investigation of oscillatory flow induced microdroplet breakup in low melting point alloy (LMPA)-in-water two-phase flow system in a microchannel. The effects of perturbation flow Weber number, and oscillating frequencies on the droplet breakup dynamics have been elucidated. Lowering the wall temperature will accelerate the solidification process of LMPA droplets, giving rise to the rapid formation of ultra-small particles with size down to 1 micron in less than 3 ms. The versatile approach combines oscillatory flow dominated droplet breakup process and phase change process, leading to the formation of LMPA microparticles with monodispersed size distribution and well-tailored properties by using a straight microchannel, which obviates the need for sophisticated design and complex fabrication process of microdevices. This work will provide a strategy to manipulating LMPA droplet size and structure for the massive production of ultra-small LMPA microparticles via a facile control over the flow conditions in the two-phase flow in a microfluidic system. It will open up for a diversity of applications of LMPA microparticles in various fields such as energy storage and thermal management. [ABSTRACT FROM AUTHOR]

Canonically PD-L1 functions as the inhibitory immune checkpoint on cell surface. Recent studies have observed PD-L1 expression in the nucleus of cancer cells. But the biological function of nuclear PD-L1 (nPD-L1) in tumor growth and antitumor immunity is unclear. Here we enforced nPD-L1 expression and established stable cells. nPD-L1 suppressed tumorigenesis and aggressiveness in vitro and in vivo. Compared with PD-L1 deletion, nPD-L1 expression repressed tumor growth and improved survival more markedly in immunocompetent mice. Phosphorylated AMPKa (p-AMPKa) facilitated nuclear PD-L1 compartmentalization and then cooperated with it to directly phosphorylate S146 of histone variant macroH2A1 (mH2A1) to epigenetically activate expression of genes of cellular senescence, JAK/STAT, and Hippo signaling pathways. Lipoic acid (LA) that induced nuclear PD-L1 translocation suppressed tumorigenesis and boosted antitumor immunity. Importantly, LA treatment synergized with PD-1 antibody and overcame immune checkpoint blockade (ICB) resistance, which likely resulted from nPD-L1-increased MHC-I expression and sensitivity of tumor cells to interferon-γ. These findings offer a conceptual advance for PD-L1 function and suggest LA as a promising therapeutic option for overcoming ICB resistance. [ABSTRACT FROM AUTHOR]

The agricultural production in China is gradually transitioning from extensive agriculture to green agriculture. In this context, identifying the driving factors and dimensions of farmers’ green production behaviour can contribute to promoting sustainable agricultural development. Existing studies lack investigation into the identification of driving factors and dimensions of green production behaviour among farmers of different scales. This study examined 1 142 farm households from five major grain-producing provinces in the North China Plain in 2019. We employed probit-ISM (interpretive structural modelling) models to analyse the driving factors of green production behaviour among farmers of different scales and identify dimensional differences. The study concluded the following: i) Personal characteristics, household characteristics, operational characteristics, social network characteristics, organisational characteristics, and cognitive characteristics were factors driving green production behaviour among small-scale farmers. However, social network characteristics and organisational characteristics had insignificant effects on green production behaviour among large-scale farmers. ii) Personal characteristics, number of agricultural workers, scale of operation, degree of land fragmentation, and whether relatives and friends are civil servants were the deep-rooted factors driving farmers’ green production behaviour. Part-time farming status, proportion of grain income, types of agricultural machinery, relationship with local farm machinery operators, and organisational characteristics were middle indirect factors. Cognitive characteristics represented the direct surface factors. This study can provide crucial information for government departments, which formulate differentiated policies to promote green production behaviour among farmers of different scales. [ABSTRACT FROM AUTHOR]

In order to improve the vibration isolation performance of current three-parameter damper using bellow and fluid damping, a concept of fluid damper with variable damping and secondary variable stiffness was proposed, a prototype has been designed with several frequency selective valves to adjust the damping characteristics at specific frequency bands, especially that in the low-frequency range. Followed mathematical modelling and simulation of the damper have been carried out, the results show that the designed damper has obtained excellent damping characteristics both in the high- and low-frequency ranges, the micro-vibration isolation efficiency of the damper under realistic excitation of a Control Moment Gyroscope used in a manned spacecraft reaches a significant 71.03 %.The proposed damper concept and designed prototype have laid the foundation for further testing and optimization of high-end isolators for modern spacecrafts. [ABSTRACT FROM AUTHOR]

Tikhonov regularization technique is widely recognized as one of the most prevalent and well-established approaches for solving linear discrete ill-posed problems. The present study introduces two novel randomized iterative algorithms for the computation of numerical solutions to large-scale Tikhonov regularization problems. The first one applies the randomized Kaczmarz algorithm to an augmented regularized normal system of equations, the second one is an accelerated version of the first one by means of greedy probability criterion. In theory, we establish some convergence results for these two algorithms. Numerical experiments demonstrate the convergence properties and illustrate the performances of these two algorithms. [ABSTRACT FROM AUTHOR]

This study introduces bis­[hexa­kis­(nitrato-κ²O,O′)lanthanum(III)] tris­[hexa­aqua­nickel(II)] hexa­hydrate, [La(NO3)6]2[Ni(H2O)6]3·6H2O, with a structure refined in the hexa­gonal space group R... The salt com­prises [La(NO3)6]3− icosa­hedra and [Ni(H2O)6]2+ octa­hedra, thus forming an intricate network of inter­penetrating honeycomb lattices arranged in layers. This arrangement is stabilized through strong hydrogen bonds. Two successive layers are connected via the second [Ni(H2O)6]2+ octa­hedra, forming sheets which are stacked perpendicular to the c axis and held in the crystal by van der Waals forces. The synthesis of [La(NO3)6]2[Ni(H2O)6]3·6H2O involves dissolving lanthanum(III) and nickel(II) oxides in nitric acid, followed by slow evaporation, yielding green hexa­gonal plate-like crystals. [ABSTRACT FROM AUTHOR]

We propose efficient and parallel algorithms for the implementation of the high-order continuous time Galerkin method for dissipative and wave propagation problems. By using Legendre polynomials as shape functions, we obtain a special structure of the stiffness matrix that allows us to extend the diagonal Padé approximation to solve ordinary differential equations with source terms. The unconditional stability, hp error estimates, and hp superconvergence at the nodes of the continuous time Galerkin method are proved. Numerical examples confirm our theoretical results. [ABSTRACT FROM AUTHOR]

This study takes the indoor substation adjacent to the elevated bridge subway line as the engineering background, investigates the structural vibration response law of the substation induced by the operation of the subway line through on-site vibration measurement, and proposes a novel nonlinear gas-spring quasi-zero stiffness isolator (NGS-QZSI) is proposed to reduce the structural vertical vibration and further reduce the safety distance. The software ABAQUS is used to establish a structure-equipment coupling numerical analysis model considering soil-structure interaction, and its effectiveness and accuracy are validated based on the measured results. The structural vibration response analysis is carried out under different vibration source distances, and a nonlinear gas-spring quasi-zero stiffness isolator is proposed to be employed for substation structural vibration isolation. The research results show that the substation structure under subway load excitation is dominated by vertical vibration, and its vibration response increases gradually with the increase of floor level. When the substation structure is less than 45 m from the subway line, the structural response exceeds the safety limit (12.5 µm/s) of the VC-C standard. With the vibration isolator attached, the structural vibration response is significantly reduced, with the peak and root mean square response controlled by more than 70 %. Particularly, the safe distance of the substation from the subway line is reduced from 45 m to 20 m. Moreover, the frequency domain result analysis indicates that the proposed nonlinear vibration isolator can effectively control the low-frequency vibration of the structure. [ABSTRACT FROM AUTHOR]

This study introduces bis[hexakis(nitrato-α²O,O')lanthanum(III)] tris[hexaaquanickel(II)] hexahydrate, [La(NO3)6]2[Ni(H2O)6]3·6H2O, with a structure refined in the hexagonal space group R[\overline{3}]. The salt comprises [La(NO3)6]3- icosahedra and [Ni(H2O)6]2+ octahedra, thus forming an intricate network of interpenetrating honeycomb lattices arranged in layers. This arrangement is stabilized through strong hydrogen bonds. Two successive layers are connected via the second [Ni(H2O)6]2+ octahedra, forming sheets which are stacked perpendicular to the c axis and held in the crystal by van der Waals forces. The synthesis of [La(NO3)6]2[Ni(H2O)6]3·6H2O involves dissolving lanthanum(III) and nickel(II) oxides in nitric acid, followed by slow evaporation, yielding green hexagonal plate-like crystals. This study introduces bis[hexakis(nitrato-K²O,O')lanthanum(III)] tris[hexaaquanickel(II)] hexahydrate, [La(NO3)6]2[Ni(H2O)6]3·6H2O, with a structure refined in the hexagonal space group R3. The salt comprises [La(NO3)6]3* icosahedra and [Ni(H2O)6]2+ octahedra, thus forming an intricate network of interpenetrating honeycomb lattices arranged in layers. This arrangement is stabilized through strong hydrogen bonds. Two successive layers are connected via the second [Ni(H2O)6]2+ octahedra, forming sheets which are stacked perpendicular to the c axis and held in the crystal by van der Waals forces. The synthesis of [La(NO3)6]2[Ni(H2O)6]3·6H2O involves dissolving lanthanum(III) and nickel(II) oxides in nitric acid, followed by slow evaporation, yielding green hexagonal plate-like crystals. [ABSTRACT FROM AUTHOR]

Entropy inequalities are crucial to the well-posedness of hyperbolic conservation laws, which help to select the physically meaningful one from among the infinite many weak solutions. Recently, several high order discontinuous Galerkin (DG) methods satisfying entropy inequalities were proposed; see [T. Chen and C.-W. Shu, J. Comput. Phys., 345 (2017), pp. 427-461; J. Chan, J. Comput. Phys., 362 (2018), pp. 346-374; T. Chen and C.-W. Shu, CSIAM Trans. Appl. Math., 1 (2020), pp. 1-52] and the references therein. However, high order numerical methods typically generate spurious oscillations in the presence of shock discontinuities. In this paper, we construct a high order entropy stable essentially oscillation-free DG (OFDG) method for hyperbolic conservation laws. With some suitable modification on the high order damping term introduced in [J. Lu, Y. Liu, and C.-W. Shu, SIAM J. Numer. Anal., 59 (2021), pp. 1299-1324; Y. Liu, J. Lu, and C.-W. Shu, SIAM J. Sci. Comput., 44 (2022), pp. A230-A259], we are able to construct an OFDG scheme with dissipative entropy. It is challenging to make the damping term compatible with the current entropy stable DG framework, that is, the damping term should be dissipative for any given entropy function without compromising high order accuracy. The key ingredient is to utilize the convexity of the entropy function and the orthogonality of the projection. Then the proposed method maintains the same properties of conservation, error estimates, and entropy dissipation as the original entropy stable DG method. Extensive numerical experiments are presented to validate the theoretical findings and the capability of controlling spurious oscillations of the proposed algorithm. [ABSTRACT FROM AUTHOR]

In this article, we investigate the growth of meromorphic solutions of ... = d4(z)η4(z) + d3(z)η3(z) + d2(z)η2(z) + d1(z)η(z) + d0(z), where a(z), bi(z) for i = 0, 1, 2 and dj(z) for j = 0, ..., 4 are given functions, △cη = η(z + c) - η(z) with c ∈ C\{0}. In particular, when the a(z), the bi(z) and the dj(z) are polynomials, and d4(z) ≡ 0, we shall show that if η(z) is a transcendental entire solution of finite order, and either deg a(z) ̸= deg d0(z)+1, or, deg a(z) = deg d0(z)+1 and ρ(η) ̸= 1 2, then ρ(η) ≥ 1. [ABSTRACT FROM AUTHOR]

In this article, we investigate some properties of meromorphic solution of the following differentialdifference equation ∑j=0n cjf (z + j) + ∑j=0n ljf(j) (z + j) + ∑j=0m djf(j) (z) -- c = (f (z + η) -- f (z) -- b)eQ, where n,m ≥ 1 are two integers, ηis a constant with |η| ≠ n, Q is a polynomial. We study the growth of solutions of a more general differential-difference equation given by Lü et al [Rest Math 74 (2019):1-18]. Meantime we obtain the relation between deg Q and p(f). [ABSTRACT FROM AUTHOR]

Objective: Noise is a kind of perceived public nuisance that is closely related to people's subjective feelings and lives. This study explores the clinical application effect of comprehensive noise reduction technology in outpatients with vitiligo. Methods: A total of 76 patients with vitiligo were selected in the Department of Dermatology at Baoding No. 2 Central Hospital from January 2020 to January 2021, as the control group (CG), receiving 5S management mode, and 80 patients with vitiligo from February 2021 to October 2022 were selected as the study group (SG), receiving comprehensive noise reduction technology combined with the 5S management mode for this retrospective study. The effects of different management modes on these patients were observed. Results: SG had higher nursing quality scores in service attitude, service initiative, communication skills, environmental management and item management and overtly a lower noise level than CG (all P < 0.001). The Hamilton Anxiety Scale (HAMA) scores of the two groups at the end of treatment were significantly lower than those on admission (P < 0.05), with SG showing a lower score than CG (P < 0.001). Correlation analysis showed that noise levels and HAMA scores had a positive correlation (r =0.423, P < 0.001). Patients with negative feelings about medical treatment caused by various noise sources in SG were obviously less than those in CG (P < 0.05). Both the groups had a statistical difference in overall satisfaction (P < 0.05). Conclusion: The investigation and data analysis demonstrated that comprehensive noise reduction in outpatients with vitiligo had a considerable effect. This technology can standardise the behaviour of medical staff, enhance nursing quality, reduce noise levels and alleviate patients' anxiety and improve their satisfaction. It has great benefits for the outpatient environment and patients. [ABSTRACT FROM AUTHOR]

Understanding the time-dependent mechanical behavior of tough and viscoelastic hydrogels under complex external loading is crucial. In this study, we utilized tough and viscoelastic hydrogels synthesized through the copolymerization of methacrylic acid and methacrylamide as a model system to investigate their mechanical behavior under multiaxial stretching across a wide range of strain rates. Three stretching modes examined were uniaxial, pure shear, and equal biaxial stretching. Our findings show that under equal biaxial stretching, the hydrogels exhibit higher mechanical properties and energy dissipation compared to uniaxial and pure shear stretching, owing to the greater contribution of hydrogen bonds to energy dissipation in the former stretching mode. Additionally, employing the time-elongation separability method during the stretching process, we observed that the relaxation of dynamic hydrogen bonds in the hydrogels only depends on stretching time, independent of the elongation ratio and stretching modes. We anticipate that this study will yield valuable contributions to the design of durable load-bearing soft materials, particularly in dealing with complex deformation and strain rate responses. [ABSTRACT FROM AUTHOR]

Chronic obstructive pulmonary disease (COPD) is a leading cause of death in the United States. Overall COPD prevalence declined during 1999-2011. Trends in COPD prevalence during the previous decade have not been reported. CDC analyzed 2011-2021 Behavioral Risk Factor Surveillance System data to assess trends and differences in self-reported physician-diagnosed COPD prevalence among U.S. adults aged =18 years. Age-standardized prevalence of COPD did not change significantly from 2011 (6.1%) to 2021 (6.0%). Prevalence was stable for most states and subgroups; however, it decreased significantly among adults aged 18-44 years (average annual percent change [AAPC] = -2.0%) and increased significantly among those aged =75 years (AAPC = 1.3%), those living in micropolitan counties (0.8%), and among current (1.5%) or former (1.2%) smokers. COPD prevalence remained elevated in the following groups: women, adults aged =65 years, those with a lower education level, unable to work, living in rural areas, and who ever smoked. Evidence-based strategies, especially those tailored for adults disproportionately affected, can reduce COPD prevalence, and address the continued need for prevention, early diagnosis, treatment, and management. [ABSTRACT FROM AUTHOR]

It is of great significance to identify the pest species accurately and control it effectively to reduce the loss of agricultural products. The research results of this project will provide theoretical basis for preventing and controlling the spread of pests and reducing the loss of agricultural products, and have important practical significance for improving the quality of agricultural products and increasing the output of agricultural products. At the same time, it provides a kind of effective prevention and control measures for farmers, so as to ensure the safety and health of crops. Because of the slow speed and high cost of manual identification, it is necessary to establish a set of automatic pest identification system. The traditional image-based insect classifier is mainly realized by machine vision technology, but because of its high complexity, the classification efficiency is low and it is difficult to meet the needs of applications. Therefore, it is necessary to develop a new automatic insect recognition system to improve the accuracy of insect classification. There are many species and forms of insects, and the field living environment is complex. The morphological similarity between species is high, which brings difficulties to the classification of insects. In recent years, with the rapid development of deep learning technology, using artificial neural network to classify pests is an important method to establish a fast and accurate classification model. In this work, we propose a novel convolutional neural network-based model (MSSN), which includes attention mechanism, feature pyramid, and fine-grained model. The model has good scalability, can better capture the semantic information in the image, and achieve more accurate classification. We evaluated our approach on a common data set: large-scale pest data set, PlantVillage benchmark data set, and evaluated model performance using a variety of evaluation indicators, namely, macro mean accuracy (MPre), macro mean recall rate (MRec), macro mean F1-score (MF1), Accuracy (Acc) and geometric mean (GM). Experimental results show that the proposed algorithm has better performance and universality ability than the existing algorithm. For example, on the data set, the maximum accuracy we obtained was 86.35%, which exceeded the corresponding technical level. The ablation experiment was conducted on the experiment itself, and the comprehensive evaluation of the complete MSSN(scale 1+2+3) was the best in various performance indexes, demonstrating the feasibility of the innovative method in this paper. [ABSTRACT FROM AUTHOR]

Based on the in situ observations, reanalysis, and model simulation, the variations in glaze dipole pattern in China and its underlying physical mechanism have been explored. The glaze dipole pattern features an out-of-phase relationship between winter glaze in the south of the Yangtze River valley (YRV) and northern China, accompanied by pronounced interdecadal variation around the late 1970s. The results from synoptic analyses suggest that cold air brought by the northerly winds and warm moist air by the southwesterly winds, as well as the occurrence of inversion layer are vital to the glaze weather in the south of YRV. Further analyses indicate that the interdecadal shift of the Pacific decadal oscillation (PDO) contributes largely to variations in glaze dipole pattern. Specifically, the warm PDO provides a beneficial environment for the occurrence of glaze dipole pattern by stimulating the tropical-extratropical circulation configuration with the deepened East Asian trough, strengthened East Asian westerly jet, anomalous anticyclone over the tropical western Pacific Ocean, and cyclone over the southern Tibetan Plateau at the decadal time scale. Consequently, the enhanced moisture transport brought by southwesterly and cold air intrusion induced by the deepened East Asian trough benefit the glaze weather in the south of YRV, while the decreased precipitation and a much lower temperature in northern China depress the generation of glaze. Moreover, the results from the CAM4 model simulation indicate the atmospheric circulation anomalies forced by PDO-like SST can roughly reproduce the extratropical configuration related to the glaze, but it has difficulties in capturing the tropical circulation anomalies. [ABSTRACT FROM AUTHOR]

The three-way decision offers new perspectives for solving uncertain decision problems, especially categorical decision-making. However, in reality, the preference information of the decision object may be vague and uncertain. To address this issue, we construct a grey relation analysis based three-way decision model in a grey system environment. First, based on an improved grey correlation similarity measure, we investigate how the conditional probabilities of decision events are constructed. Subsequently, according to the information entropy, we established the objective optimization model and calculated the optimal weight of each index. Considering the delay cost and the uncertainty of the loss function, the grey relative loss function matrix is constructed based on the uncertain information of decision objects. Based on this, we establish the optimal thresholds method with the relative loss function and devise the decision rules. Using the established decision rules, we can obtain the classification results of all decision objects. Finally, the proposed model is used to deal with the users' classification problems in the movie recommendation system, which demonstrates the validity and feasibility of the model. [ABSTRACT FROM AUTHOR]

Transverse rectangular microgrooves with local machining flaw are investigated using direct numerical simulations from the viewpoint of suppressing the second-mode instability in a Mach 6 hypersonic boundary layer. Two types of machining flaw are modeled for the local deformation of microgrooves, i.e., chamfered and protruded ones. The effect of locally deformed microgrooves on the boundary-layer stability is studied by superposing the second-mode disturbance to the base flow of the boundary layer. The investigated unstable second mode is 400 kHz, and the microgrooves are installed in its synchronous region. The results show that compression and expansion waves are generated on the surface of the deformed microgrooves, and microscale separation bubbles are formed at the rear edge of the deformed microgrooves. With the increase of local deformation height of microgrooves, the suppression effect of the second-mode disturbance gradually increases. As the deformation height reaches 0.09 mm, the amplitude inhibition rate of locally deformed microgrooves on the second-mode disturbance reaches 44.7%, compared to that of the regular one. [ABSTRACT FROM AUTHOR]

Precision involute artifact is an indispensable tool in the detection of high precision gears. In this paper, a new method of low-frequency vibration-aided wire electrochemical machining (LV-WECM) is proposed to fabricate gear involute artifact with high aspect ratio. First, a mathematical model of WECM is established to analyze forming principle of gear involute artifact. Second, the machining process is simulated by electric field simulation. The deviation of WECM is analyzed according to the simulation results. And then, the effects of low-frequency vibration and flushing on machining are analyzed by flow field simulation, which shows that vibration and flushing can effectively promote mass transfer in the gap. Finally, the effects of applied voltage, pulse parameters, and vibration parameters on machining accuracy were discussed experimentally. After several groups of contrast experiments, a gear involute artifact blank with aspect ratio of 40:1 is successfully machined on 8-mm-thick GCr15 workpiece, the max profile deviation is 17.6 µm, and the average surface roughness Sa is about 2.370 µm. It is proved that LV-WECM is a reliable method for machining involute template with high aspect ratio. [ABSTRACT FROM AUTHOR]

The distributed kernel ridge regression (DKRR) has shown great potential in processing complicated tasks. However, DKRR only made use of the local samples that failed to capture the global characteristics. Besides, the existing optimal learning guarantees were provided in expectation and only pertain to the attainable case that the target regression lies exactly in the kernel space. In this paper, we propose distributed learning with globally-shared Nyström centers (DNyström), which utilizes global information across the local clients. We also study the statistical properties of DNyström in expectation and in probability, respectively, and obtain several state-of-the-art results with the minimax optimal learning rates. Note that, the optimal convergence rates for DNyström pertain to the non-attainable case, while the statistical results allow more partitions and require fewer Nyström centers. Finally, we conduct experiments on several real-world datasets to validate the effectiveness of the proposed algorithm, and the empirical results coincide with our theoretical findings. [ABSTRACT FROM AUTHOR]

According to a conjecture by C. C. Yang [Houston J Math 45 (2019):431-437], if ω(z)ω(k)(z) is a periodic function, where ω(z) is a transcendental entire function and k is a positive integer, then ω(z) is also a periodic function. We consider the related questions, which can be viewed as differential-difference versions of Yang's conjecture. We discuss the periodicity of a transcendental entire function ω(z) when differential-difference polynomials in ω(z) are periodic. [ABSTRACT FROM AUTHOR]

Based on the "Internet +" concept in 2012 and the "Targeted Poverty Alleviation" strategy in 2013, many companies have found new ways to alleviate poverty through the "Internet +", which has injected new vitality into impoverished area, and also helped enterprises to promote their development in the course of poverty alleviation. This paper aims to promote the development of enterprises in the process of poverty alleviation through literature analysis and case studies. This paper intends to help more companies understand the role of "Internet +" in poverty alleviation through literature analysis and case studies, as well as how to consolidate the results of poverty alleviation and prevent the return of poverty with effective poverty alleviation methods, so as to achieve the simultaneous development of poverty alleviation and company business. [ABSTRACT FROM AUTHOR]

The thermodynamical model for rotating disk electrodes for second order ECE (electrochemical-chemical-electrochemical) reactions is considered, and the effect of concentrations of three species on the current for ECE reaction is theoretically analyzed, and the optimal current value is obtained. The Taylor series method is used, the derivation is simple and the accuracy can be improved if higher order Taylor series is considered. A fractal modification is also suggested for future research. [ABSTRACT FROM AUTHOR]

A family of variational principles is obtained for the 1-D inviscid flow by Ji-Huan He's semi-inverse method. The invalidy of the Lagrange multiplier method, e. g., the Lagrange crisis, is also discussed to eliminate constraints of a constrained variational principle. Two approaches to the elimination of the crisis are elucidated. [ABSTRACT FROM AUTHOR]

Objectives: This article starts with increasing emotions through cognitive reappraisal and explores the impact of state gratitude emotions on interpersonal trust among college students under cognitive reappraisal. Method: In study 1, we used a questionnaire survey and experimental design to collect data, which we processed/analyzed using SPSS 23.0. We employed, the Rotter Interpersonal Trust Scale (ITS), as adapted by Xu Huiyan, consisting of 25 items, to measure the interpersonal trust levels among college students and to explore the potentially significant differences in interpersonal trust levels among the students based on their demographic variables, including gender. We collected 347 survey questionnaires, with 143 from males and 204 from females, with a mean age of 20.93 (SD = 2.703). In study 2, we utilized a univariate inter-subject experimental design, with the independent variable being the state gratitude emotion (awakened vs. not awakened) under cognitive reappraisal, and the dependent variable was the level of interpersonal trust. Thirty participants participated in the pre-experiment, followed by 119 participants in the formal experiment to assess the impact of state gratitude emotion on interpersonal trust among college students, using motivation reappraisal strategy (t = − 4.028, p < 0.01). Results: This study found that (1) the overall interpersonal trust of college students was moderate to low (M = 38.01, SD = 9.13); (2) no significant differences in interpersonal trust levels were found among college students based on gender, grade, and whether they had children; however, the significant differences in interpersonal trust levels were observed among college students based on their the area of residence (F = 3.675, p < 0.05), school type (F = 3.04, p < 0.05), and family type (t = − 3.034, p < 0.01); (3) cognitive reappraisal has been shown to enhance individuals' gratitude emotions in situations, thereby, raising their interpersonal trust level. Conclusions: We conclude that cognitive reappraisal enhances individuals' positive emotions and levels of interpersonal trust in social interactions, offering a reference for promoting positive emotions and interpersonal trust levels among college students. [ABSTRACT FROM AUTHOR]

In this paper, we develop an essentially oscillation-free discontinuous Galerkin method for systems of hyperbolic conservation laws. Based on the standard discontinuous Galerkin method, the numerical damping terms are introduced so as to control the spurious oscillations, similar to the scalar case [J. Lu, Y. Liu, and C.-W. Shu, SIAM J. Numer. Anal., 59 (2021), pp. 1299--1324]. We use both the classical Runge--Kutta method and the modified exponential Runge--Kutta method in time discretization. Particularly, the latter one could avoid additional restrictions of time step size due to the numerical damping. Extensive numerical experiments are shown to demonstrate our algorithm is robust and effective. [ABSTRACT FROM AUTHOR]

Model hubs with many pre-trained models (PTMs) have become a cornerstone of deep learning. Although built at a high cost, they remain under-exploited|practitioners usually pick one PTM from the provided model hub by popularity and then fine-tune the PTM to solve the target task. This naïve but common practice poses two obstacles to full exploitation of pre-trained model hubs: first, the PTM selection by popularity has no optimality guarantee, and second, only one PTM is used while the remaining PTMs are ignored. An alternative might be to consider all possible combinations of PTMs and extensively fine-tune each combination, but this would not only be prohibitive computationally but may also lead to statistical over-fitting. In this paper, we propose a new paradigm for exploiting model hubs that is intermediate between these extremes. The paradigm is characterized by two aspects: (1) We use an evidence maximization procedure to estimate the maximum value of label evidence given features extracted by pre-trained models. This procedure can rank all the PTMs in a model hub for various types of PTMs and tasks before fine-tuning. (2) The best ranked PTM can either be fine-tuned and deployed if we have no preference for the model's architecture or the target PTM can be tuned by the top K ranked PTMs via a Bayesian procedure that we propose. This procedure, which we refer to as B-Tuning, not only improves upon specialized methods designed for tuning homogeneous PTMs, but also applies to the challenging problem of tuning heterogeneous PTMs where it yields a new level of benchmark performance. [ABSTRACT FROM AUTHOR]

Excessive alcohol use* is associated with disease, injury, and poor pregnancy outcomes and is responsible for approximately 95,000 deaths in the United States each year (1). Binge drinking (five or more drinks on at least one occasion for men or four or more drinks for women) is the most common and costly pattern of excessive alcohol use (2). CDC analyzed data from the 2018 Behavioral Risk Factor Surveillance System (BRFSS) to estimate past 30-day binge drinking prevalence, frequency, and intensity (number of drinks per occasion), overall and by select characteristics and state. The overall unadjusted prevalence of binge drinking during the past 30 days was 16.6%, representing an estimated 38.5 million U.S. adults aged ≥18 years; prevalence was highest (26.0%) among those aged 25-34 years. The age-standardized binge drinking prevalence was higher among men (22.5%) than among women (12.6%), increased with income, and was highest among non-Hispanic White adults and adults in the Midwest Census region. State-level age-standardized binge drinking prevalence ranged from 10.5% (Utah) to 25.8% (Wisconsin). Among adults who reported binge drinking, 25.0% did so at least weekly, on average, and 25.0% consumed at least eight drinks on an occasion. To reduce binge drinking, the Community Preventive Services Task Force recommends increasing alcohol taxes and implementing strategies that strengthen regulations to reduce alcohol availability.† The U.S. Preventive Services Task Force recommends clinicians screen adults for alcohol misuse in primary care settings and provide counseling as needed.§. [ABSTRACT FROM AUTHOR]

We investigate experimentally and theoretically the influence of electron transport layer (ETL) thickness on properties of typical N,N'-diphenyl-N,N'-bis(1-naphthyl)-[1,1'-biphthyl]-4,4'-diamine (NPB)/tris-(8-hydroxyquinoline) aluminum (Alq3) heterojunction based organic light-emitting diodes (OLEDs), where the thickness of ETL is varied to adjust the distance between the emitting zone and the metal electrode. The devices showed a maximum current efficiency of 3.8 cd/A when the ETL thickness is around 50 nm corresponding to an emitter-cathode distance of 80 nm, and a second maximum current efficiency of 2.6 cd/A when the ETL thickness is around 210 nm corresponding to an emitter-cathode distance of 240 nm. We adopt a rigorous electromagnetic approach that takes parameters, such as dipole orientation, polarization, light emitting angle, exciton recombination zone, and diffusion length into account to model the optical properties of devices as a function of varying ETL thickness. Our simulation results are accurately consistent with the experimental results with a widely varying thickness of ETL, indicating that the theoretical model may be helpful to design high efficiency OLEDs. [ABSTRACT FROM AUTHOR]

In this paper, we propose a novel discontinuous Galerkin (DG) method to control the spurious oscillations when solving the scalar hyperbolic conservation laws. Usually, the high order linear numerical schemes would generate spurious oscillations when the solution of the hyperbolic conservation laws contains discontinuities. The spurious oscillations may be harmful to the numerical simulation, as it not only generates some artificial structures not belonging to the problems, but also causes many overshoots and undershoots that make the numerical scheme less robust. To overcome this difficulty, in this paper we introduce a numerical damping term to control spurious oscillations based on the classic DG formulation. In comparison to the classic DG method, the proposed DG method still maintains many good properties, such as the extremely local data structure, conservation, L²-boundedness, optimal error estimates, and superconvergence. We also provide some numerical examples to show the good performance of the proposed DG scheme and verify our theoretical results. [ABSTRACT FROM AUTHOR]

(K0.48Na0.52)0.98Sr0.01NbO3+xmol%SnO2 (KNSN-xSn, x=0,0.5,1.0,1.5) leadfree piezoceramics were fabricated by the conventional solid state reaction method. The compositional dependence of microstucture, phase structure, defect structure and electrical properties of the ceramics was systemically investigated. XRD patterns revealed that all the ceramic samples possessed pure perovskite structure. At x=0.5, the ceramic exhibited the optimum electrical properties (d33 = 137 pC/N, kp = 38.5%, tanδ=0.04, Qm = 114 and Tc = 401 °C), suggesting that this ceramic is a promising lead-free piezoelectric candidate for piezoelectric applications. [ABSTRACT FROM AUTHOR]

Antibacterial dressings play an important role in wound management, especially in chronic wounds. Due to the excellent water retention, antibacterial hydrogel has become an ideal wound dressing. In this paper, the effective antibacterial dressing was constructed with the poly N-isopropylacrylamide (PNIPAM) hydrogel and graphene oxide loading nanosilver particles (GO-Ag) by the in situ chemical crosslinking method. The molecular structure, viscosity and mechanical properties, antibacterial agent content, antibacterial performance, temperature-sensitive antibacterial relationship and biocompatibility of PNIPAM-based GO-Ag composite hydrogel (PNIPAM/GO-Ag) were systematically characterized by the scanning electron microscopy (SEM), infrared spectroscopy (FT-IR), plate counting and other methods. The results showed that the introduction of GO-Ag increased the pore structure of PNIPAM/GO-Ag hydrogel and provided more active sites for the release of silver nanoparticles, wherein the content of nanosilver in PNIPAM/GO-Ag hydrogel was only 0.01%, meeting the requirements of application as antibacterial dressings. Moreover, when the hydrogel was subjected to heat contraction, silver nanoparticles could release more quickly and efficiently. The antibacterial rates of the PNIPAM/GO-Ag hydrogel against E. coli and S. aureus were 99.8 and 99% at 37 °C, respectively, higher than those at 25 °C (92, 95%). Compared with the pure PNIPAM hydrogel (1423.0%), the swelling rate of PNIPAM/GO-Ag hydrogel could reach 2024.6%, certifying its ability to absorb exudate of wound site. When the deformation was less than 80%, the hydrogel could maintain excellent elastic deformation recovery ability, and the viscosity of hydrogel at human body temperature was 38 Pa·s. These prove that it had a good fit with the skin, could dissipate more energy and restore shape. The hemolysis rate of PNIPAM/GO-Ag hydrogel was less than 5%, showing good bio-safety. These all demonstrated the PNIPAM/GO-Ag hydrogel can be used as a potential application for the skin wound dressing. [ABSTRACT FROM AUTHOR]

Automatic detection of tomato leaf spot disease is essential for control and loss reduction. Traditional algorithms face challenges such as large amount of data, multiple training and heavy computation. In this study, a lightweight shared Siamese neural network method was proposed for tomato leaf disease identification, which is suitable for resource‐limited environments. Experiments on Plant‐Village, Taiwan and Taiwan ++ datasets show that the accuracy fluctuates very little even when trained with only 60% of the data, which confirms the effectiveness of the proposed method in the small data environment. In addition, compared with the mainstream algorithms, it improves the accuracy by up to 35.3%on Plant‐Village and two Taiwan datasets respectively. The experimental results also show that the proposed method still performs well when the data is imbalanced and the sample size is small. [ABSTRACT FROM AUTHOR]

Background: Our study aims to enhance the understanding of lymph node venous networks (LNVNs) by summarising their anatomical, sonographic features, and reflux patterns. Method: We examined 241 legs from 141 patients with primary chronic venous disease (CVD) using duplex ultrasound. Results: The findings indicated variations in the shape, size, vascularity, and echogenicity of LNVN. The superficial inguinal lymph node with reflux appeared slightly larger, exhibiting higher velocities in the hilar artery. Regarding connections, venous flow within LNVN was predominantly drained through the saphenofemoral junction (SFJ), anterior accessory great saphenous vein (AAGSV), and great saphenous vein (GSV). A significant number of LNVNs were observed to be associated with anterolateral thigh tributaries. The study also identified valve cusps within LNVN. Conclusion: This study revealed a 12% prevalence of primary LNVN. Understanding the anatomical and haemodynamic features of LNVN informs treatment strategies and potentially helps prevent the recurrence of varicose veins. [ABSTRACT FROM AUTHOR]

Ritz method is widely used in variational theory to search for an approximate solution. This paper suggests a Ritz-like method for integral equations with an emphasis of pantograph delay equations. The unknown parameters involved in the trial solution can be determined by balancing the fundamental terms. [ABSTRACT FROM AUTHOR]

The differential model for electrochemical capacitors under dynamical cycling results in discontinuity of the electric current. This paradox makes theoretical analysis of the electrochemical capacitors much difficult, and there is not universal approach to treatment of the problem. This paper finds that the fractal calculus can be powerfully applied to the problem, and a continuous electric current can be obtained as it should be. [ABSTRACT FROM AUTHOR]

In the application process of China's independently produced new aluminum alloy 211z.1 into high-end military and civilian industries, a great many holes are needed for fastening connection. However, the severe wear of the cutting edge of twist drill is an important factor that restricts the quality of hole processing and tool life. In this paper, the wear condition of the standard high-speed steel twist drill in drilling the new aluminum alloy 211z.1 is studied based on the drilling test, and the influence law of the drilling amount on the tool wear is revealed by designing a reasonable drilling test plan. The research results show that the cutting speed has a significant effect on the flank wear, and the drilling feed and the drilling height have relatively little influence on the flank wear of the tool. [ABSTRACT FROM AUTHOR]

• The frequencies of circulating TPH cells, ICOS + TPH cells, and CD28 + TPH cells were higher in PBC patients. • Higher levels of ICOS + TPH and CD28 + TPH cell in cirrhotic patients than in noncirrhotic patients. • TPH cell activation status is associated with the severity of PBC. Peripheral helper T (TPH) cells, a recently defined subset of Th cells, promote B cell differentiation and antibody production in inflamed tissues. This study investigated whether circulating TPH cells are associated with primary biliary cholangitis (PBC), a typical organ-specific autoimmune disease. Twenty PBC patients and 20 age- and sex-matched healthy controls (HCs) were recruited. The circulating TPH cell subsets were analyzed by flow cytometry, and the associations of TPH cells with disease activity and plasma cells were determined. Functional analysis was performed using a TPH and B cell coculture experiment. The frequencies of circulating TPH cells, ICOS+ TPH cells, and CD28+ TPH cells were increased in patients with PBC. Furthermore, the ICOS+ TPH cell level was higher in PBC patients with or without cirrhosis than in HCs, and the level decreased after treatment. Moreover, ICOS+ TPH cell levels correlated positively with specific clinical parameters (including anti-mitochondrial antibodies against M2 antigen (AMA-M2), IgM) and plasma cell levels, suggesting that the TPH cell activation status is associated with the severity of PBC. Coculture results revealed an enhanced ability of TPH cells from PBC patients to induce B cell differentiation. Elevated numbers of TPH cells may be involved in the pathogenesis of PBC, and the activation status of TPH cells is related to the severity of PBC. Additionally, TPH cells can be used as a useful biomarker for evaluating the progression of PBC and may serve as a therapeutic target for PBC patients in the future. [ABSTRACT FROM AUTHOR]

We propose a two greedy subspace Kaczmarz algorithm for solving consistent systems of linear equations. At each step, our proposed algorithm projects the current iterate onto the solution space given by two greedily selected rows. It is proved that this algorithm converges to the unique solution of the consistent linear system. Numerical results on Gaussian models as well as on image reconstruction problems show that the proposed algorithm improves the convergence rate of the greedy randomized Kaczmarz algorithm. [ABSTRACT FROM AUTHOR]

Physical experiments are conducted to study the interaction between the tsunami-like waves and the horizontal plate. The surface evolution and wave-induced loads are measured to explore the hydrodynamic characteristics when different waves are employed to simulate the tsunami. The solitary wave, surge wave, and undular bore are generated in laboratory as the simplification of the offshore tsunami wave. The bottom-fixed plate places near the free surface. It is found that the elevated plate attenuates the solitary waves locally, while the submerged plate leads to the wave focus phenomenon. The plate has less influence on the surface variation of the surge wave propagating. Results of loads show the different loading process of each tsunami-like wave. The inertial wave force and the local pressure from the rising surface dominate the inline force and vertical force, respectively. The value of loads induced by the surge wave is less than that of the solitary wave. The undular bore is generated by the superimposition of the solitary wave on the surge wave. The part of the solitary wave plays a local role in the wave force, while the surge part dominates the surface evolution. [ABSTRACT FROM AUTHOR]

The Silk Road pattern (SRP) is a well-known teleconnection pattern along the upper-level westerly jet over the Eurasian continent during boreal summer. The SRP has experienced an interdecadal change around the late 1970s. The present study identified a new change of the SRP around the late 1990s, which is characterized by significant weakening and zonal phase shift of the major centers of the SRP during the recent decades. The recent reshaping of the SRP is attributed to an enhanced impact of precipitation anomalies over the northeastern Indian summer monsoon (ISM), which is associated with the leading mode change of the ISM precipitation anomalies around the late 1990s. The interdecadal weakening of the upper-level westerly jet over central and East Asia also favors the southward movement of the SRP during recent periods. The differences of the features, climate impact, and causes related to the recent SRP change from those related to the SRP change around the late 1970s are also contrasted in this study. [ABSTRACT FROM AUTHOR]

Tank sloshing in a liquid cargo ship will cause instability or even overturning of its carrier if the external wave frequency is close to the natural frequency of the tank. The inherent damping of a tank without inner structures has been found to be insufficient for suppressing violent sloshing motion. A variety of damping plates have been designed to increase the inherent damping of the tank. Of them, a horizontal perforated plate (HPP) has been proved to be effective for dissipating energy in a swaying tank through experiments. In this study, the sloshing problem in a tank with an HPP under swaying and rolling excitation is analytically studied based on the potential theory. The quadratic pressure loss boundary at the perforated plate is adopted, and the matched eigenfunction expansion method (MEEM) with iterative calculations is used to develop the analytical model. Based on the different porosities and submerged depths of the plate, both the free surface elevations and the hydrodynamic coefficients are carefully examined. The results give a better understanding in the effect of the inner HPP on the sloshing motion in the ship tank. [ABSTRACT FROM AUTHOR]

Tank sloshing in a liquid cargo ship will cause instability or even overturning of its carrier if the external wave frequency is close to the natural frequency of the tank. The inherent damping of a tank without inner structures has been found to be insufficient for suppressing violent sloshing motion. A variety of damping plates have been designed to increase the inherent damping of the tank. Of them, a horizontal perforated plate (HPP) has been proved to be effective for dissipating energy in a swaying tank through experiments. In this study, the sloshing problem in a tank with an HPP under swaying and rolling excitation is analytically studied based on the potential theory. The quadratic pressure loss boundary at the perforated plate is adopted, and the matched eigenfunction expansion method (MEEM) with iterative calculations is used to develop the analytical model. Based on the different porosities and submerged depths of the plate, both the free surface elevations and the hydrodynamic coefficients are carefully examined. The results give a better understanding in the effect of the inner HPP on the sloshing motion in the ship tank. [ABSTRACT FROM AUTHOR]

For each positive integer n ≤ 34, we construct traveling waves with small speed for the Gross-Pitaevskii equation, by gluing n(n + 1)/2 pairs of degree ±1 vortice of the Ginzburg- Landau equation. The location of these vortices is symmetric in the plane and determined by the roots of a special class of Adler-Moser polynomials, which are originated from the study of the Calogero-Moser system and rational solutions of the KdV equat ion. The construction still works for n > 34, under the additional assumption that the corresponding Adler-Moser polynomials have no repeated roots. It is expected that this assumption holds for any n ∈ ℕ. [ABSTRACT FROM AUTHOR]

Bioethanol production from syngas using acetogenic bacteria has attracted considerable attention in recent years. However, low ethanol yield is the biggest challenge that prevents the commercialization of syngas fermentation into biofuels using microbial catalysts. The present study demonstrated that ethanol metabolism plays an important role in recycling NADH/NAD+ during autotrophic growth. Deletion of bifunctional aldehyde/alcohol dehydrogenase (adhE) genes leads to significant growth deficiencies in gas fermentation. Using specific fermentation technology in which the gas pressure and pH were constantly controlled at 0.1 MPa and 6.0, respectively, we revealed that ethanol was formed during the exponential phase, closely accompanied by biomass production. Then, ethanol was oxidized to acetate via the aldehyde ferredoxin oxidoreductase pathway in Clostridium ljungdahlii. A metabolic experiment using 13C-labeled ethanol and acetate, redox balance analysis, and comparative transcriptomic analysis demonstrated that ethanol production and reuse shared the metabolic pathway but occurred at different growth phases. [ABSTRACT FROM AUTHOR]

Osteoblast cells are responsible for synthesizing new bone tissue, and determining how to control osteoblastic differentiation is vital to the treatment of osteoporosis. In the present study, we show that pentraxin 3 (PTX3) signaling is involved in the regulation of osteoblastic differentiation in MC3T3-E1 cells. Our data reveal that PTX3 is abundantly expressed in MC3T3-E1 cells and that its expression is inducible by the introduction of osteogenic induction medium (OIM). Overexpression of PTX3 was observed to significantly increase the expression of four osteoblast signature genes, including Runt-related transcription factor 2 (RUNX2), alkaline phosphatase (ALP), osteocalcin (OCN) and osterix (OSX), suggesting that the overexpression of PTX3 promotes osteoblastic differentiation. The relative level of gene expression between OIM and OIM plus overexpressed PTX3 was evaluated using the Affymetrix Gene Chip® mouse gene microarray. PTX3-related differentially expressed genes (DEGs) were screened. Gene ontology (GO) functional and Kyoto Encyclopedia of Genes and Genomes database (KEGG) pathway enrichment analyses were performed, and the PI3K/Akt signaling pathway was primarily involved in the osteogenic differentiation of PTX3. Protein-protein interactions (PPIs) were also constructed, and themolecular complex detection (MCODE) plugin calculated modules of PPI networks. Moreover, we show that the effect of PTX3 is mediated by its induction of the PI3K/Akt signaling pathway. Mechanistically, we show that the action of PTX3 requires the activation of PI3K and Akt, and deactivation of PI3K by its inhibitor LY294002 weakens the PTX3-mediated induction of osteoblast signature genes, ALP and matrix mineralization. The present study revealed a new role played by PTX3 and suggest a potential mechanism governing the osteoblastic differentiation of MC3T3-E1 cells. [ABSTRACT FROM AUTHOR]

In this study, a carbon shell was coated on Fe3O4 nanoparticles using a hydrothermal method followed by modification of carboxyl end groups on the Fe3O4@C to form Fe3O4@C-COOH for creating an immobilisation agent for remediating lead-contaminated soils. The surface of an Fe3O4@C nanoparticle was successfully covered with carboxyl end groups. The Fe3O4 core possessed the superparamagnetism property; the carbon shell protected the core from being oxidised or dissolved in acid solution, and provided good modifiability. Due to the strong interaction between lead and carboxyl end groups, this synthesised remediation agent exhibited high adsorption capacity. The Fe3O4@C-COOH nanoparticles principally promoted the transformation of lead (Pb) from a reducible to residual state, while having no obvious effect on the oxidation state of the lead. The amount of Fe3O4@C-COOH and the composition of soil organic matter had a higher influence on Pb distribution than soil pH, water content, or conductivity. Under optimal immobilisation conditions, the fractionation of the Pb acid-soluble, reducible, oxidative, and residual states in the contaminated soil changed significantly. The leaching and migration of Pb were significantly reduced, thus achieving remediation of lead-contaminated soils by immobilisation. Thus, remediation of lead-contaminated soils via Fe3O4@C-COOH immobilisation is a potentially practical and technologically feasible method. [ABSTRACT FROM AUTHOR]

The electrospinning process is greatly affected by the instability of Taylor cone, an instable point can eject a jet, and multiple instable points can produce multiple jets. A fractal-like multi-jet phenomenon was found in electrospinning process with auxiliary electrodes, and main factors affecting the spinning process were studied experimentally, which included solution viscosity, surface tension, and conductivity. The fractal-like multi-jet is feasible to control the fiber morphology and its output. [ABSTRACT FROM AUTHOR]

Background: In December 2019, an outbreak of a novel coronavirus disease (COVID-19; previously known as 2019-nCoV) was reported in Wuhan, Hubei province, China, which has subsequently affected more than 200 countries worldwide including Europe, North America, Oceania, Africa and other places. The number of infected people is rapidly increasing, while the diagnostic method of COVID-19 is only by nucleic acid testing. Objective: To explain the epidemiological characteristics, clinical features, imaging manifestations and to judge diagnostic value of COVID-19 by analyzing the clinical data of COVID-19 suspected and confirmed patients in a non-outbreak, Shanghai, China. To clarify the early epidemiology and clinical characteristics about COVID-19. Methods: Cross-sectional, single-center case reports of the 86 patients screened at Zhoupu Hospital in Pudong New District, Shanghai, China, from January 23 to February 16, 2020. Epidemiology, demography, clinical, laboratory and chest CTs were collected and analyzed. The screened patients were divided into COVID-19 and non-COVID-19 based on nucleic acid test results. Results: Of the 86 screened patients, 11 were confirmed (12.8%) by nucleic acid testing (mean age 40.73 ± 11.32, 5 males). No significant differences were found in clinical symptoms including fever, cough, dyspnea, sore throat, and fatigue (P > 0.05). No statistical difference was observed in plasma C-reactive protein (CRP) between the two groups (COVID-19 and non-COVID-19 ) of patients (P = 0.402), while the white blood cell count and lymphocyte count of the confirmed patients were slightly lower than those of the suspected patients (P < 0.05). Some non-COVID-19 chest CTs also showed subpleural lesions, such as ground-glass opacities (GGO) combined with bronchiectasis; or halo nodules distributed under the pleura with focal GGO; consolidation of subpleural distribution or combined with air bronchi sign and vascular bundle sign, etc. Conclusion: The early clinical manifestations and imaging findings of COVID-19 are not characteristic in non-outbreak areas. Etiological testing should be performed as early as possible for clinically suspected patients. [ABSTRACT FROM AUTHOR]