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On 10 June 2021, the Data Security Law of the People’s Republic of China (hereinafter the “DSL”) was adopted at the 29th session of the Standing Committee of the 13th National People’s Congress, effective as of 1 September 2021. The DSL is the fundamental law in the data security sphere and, together with the Cybersecurity Law (hereinafter the “CSL”) and the Personal Information Protection Law (hereinafter the “PIPL”), outlines the data regulatory framework in China. The DSL contains seven chapters and 55 articles that widely cover data security mechanisms, obligations and liabilities at both State administration and data handler levels. In this article, the key contents of the DSL together with the intensively promulgated supplemental laws and regulations will be analyzed to provide a comprehensive grasp of data security supervision in China. Specifically, section one explains the basic concepts of the DSL, section two highlights the key data security protection mechanisms such as the Important Data protection and data cross-border transfer and section three will summarize the main compliance obligations for companies to effectively put laws into actions.

Unlike the widely used eigen-buckling theory, the nonlinear post-buckling analysis provides a more accurate stability model of piezoelectric cylindrical shells and predicates more reliable instability characteristics. In this paper, an accurate post-buckling analysis of piezoelectric functionally graded cylindrical shells under combined electro-thermo-mechanical loadings is performed. The nonlinear large deflection governing equations involving the self-induced electric potential are established based on the higher-order shear deformation theory. The post-buckling equilibrium paths with mode-jumping phenomenon for both symmetric and asymmetric deformation modes are obtained by the Galerkin's method enriched with new displacement functions. Results indicate that the symmetric mode usually occurs for a thick shell and the asymmetric mode only occurs for an ultrathin shell. Furthermore, it is demonstrated that the effect of power law index highly depends on the external electro-thermal loadings. Therefore, the loading capacity of the piezoelectric FG cylindrical shells can be improved by an appropriately selected power law index.

Multidrug resistance (MDR) remains a significant impediment to chemotherapy during cancer therapy. In this study, the amphiphilic biomaterials PEI-TOS and HA-QU were synthesized to self-assemble into PEI-TOS/HA-QU core–shell micelles for the targeted codelivery of paclitaxel (PTX) and quercetin (QU) to alleviate multidrug drug resistance and enhance therapeutic efficacy. The PTX-loaded micelles possessed a uniform particle size (167.60 ± 8.185 nm), stable negative charge (–19.13 ± 0.321 mV), and pH-responsive drug release with good compatibility. The drug-loaded micelles increased the chemosensitivity of MDR tumor cells (MDA-MB-231/MDR1) to PTX and activated mitochondria-dependent apoptotic pathways (the IC50 was 2.22-fold lower than that of PTX alone). Moreover, PEI-TOS/HA-QU micelles increased the cellular uptake of lipophilic antitumor drugs by downregulating P-gp expression in MDA-MB-231/MDR1 cells. Compared with Taxol, PTX-loaded PEI-TOS/HA-QU micelles presented excellent antitumor efficacy in tumor-bearing mice, with an average tumor size that was 3.7-fold lower than that of the control group. The drug-loaded formulation showed low in vitro / in vivo toxicity and better tumor accumulation than the free drug, which led to a high tumor inhibition rate of 80.56% and considerable biocompatibility. This work describes a new platform for the codelivery of lipophilic anticancer drugs and natural active ingredients such as PTX and QU for the treatment of MDR cancer cells.

An accurate model for vibration of a porous magneto-electro-thermo-elastic functionally graded (METE-FG) cylindrical shell made of barium titanate (BaTiO3) and cobalt diiron tetraoxide (CoFe2O4) with magneto-electro-thermal loadings is proposed within the framework of Hamiltonian system. Four types of porosity distribution profiles in the thickness direction are considered. By introducing a new total eigenvector, the higher-order governing differential equations are transformed into a set of lower-order equations. The exact solution for free vibration of METE-FG shells can be expanded in terms of specific symplectic eigenfunctions having seven possible explicit forms. Subsequently, analytical frequency equations and vibration mode shapes for METE-FG shells with various boundary conditions are derived simultaneously. A comparison study is presented to demonstrate the accuracy of the proposed model and very good agreement is observed. The effects of material properties and magneto-electro-thermal loadings on free vibration characteristics of METE-FG cylindrical shells are analyzed and discussed in detail.

Carbonaceous fractions throughout the normal period and lockdown period (LP) before and during COVID-19 outbreak were analyzed in a polluted city, Zhengzhou, China. During LP, fine particulate matters, elemental carbon (EC), and secondary organic aerosol (SOC) concentrations fell significantly (29%, 32% and 21%), whereas organic carbon (OC) only decreased by 4%. Furthermore, the mean OC/EC ratio increased (from 3.8 to 5.4) and the EC fractions declined dramatically, indicating a reduction in vehicle emission contribution. The fact that OC1-3, EC, and EC1 had good correlations suggested that OC1-3 emanated from primary emissions. OC4 was partly from secondary generation, and increased correlations of OC4 with OC1-3 during LP indicated a decrease in the share of SOC. SOC was more impacted by NO

The middle route of the South-to-North Water Diversion Project is one of the crucial frameworks of China’s water network and an essential channel for water resource allocation in North China. The safe operation of the project has a huge impact on regional economic development, social stability and other aspects. The objectives of this research are to improve the disposal efficiency of all kinds of accidents during the operation of the Middle Route of the South-to-North Water Diversion Project, reduce people’s property losses and ensure the safety of water supply along the line. This paper will put forward a new emergency decision-making method based on case-based reasoning technology and prospect theory. The method is divided into two parts: (1) Collecting the historical case information and building the case library. The frame representation in the case-based reasoning technology is used to describe the characteristics of historical cases and adopt the two-level method of historical cases fast retrieval and similarity fuzzy matching retrieval to complete the preliminary selection of emergency plans; (2) The decision-making and optimization model of disposal plans based on prospect theory, namely, using the value function and probability weight classification to measure the prospect value of similar schemes and selecting the optimal disposal scheme, in order to improve the science and rationality of the decision-making results. Finally, examples are taken to verify the feasibility and effectiveness of the method.

Urban parks have been proven to cool the surrounding environment, and can thus mitigate the urban heat island to an extent by forming a park cooling island. However, a comprehensive understanding of the mechanism of park cooling islands is still required. Therefore, we studied 32 urban parks in Jinan, China and proposed absolute and relative indicators to depict the detailed features of the park cooling island. High-spatial-resolution GF-2 images were used to obtain the land cover of parks, and Landsat 8 TIR images were used to examine the thermal environment by applying buffer analysis. Linear statistical models were developed to explore the relationships between park characteristics and the park cooling island. The results showed that the average land surface temperature (LST) of urban parks was approximately 3.6 °C lower than that of the study area, with the largest temperature difference of 7.84 °C occurring during summer daytime, while the average park cooling area was approximately 120.68 ha. The park cooling island could be classified into four categories—regular, declined, increased, and others—based on the changing features of the surrounding LSTs. Park area (PA), park perimeter (PP), water area proportion (WAP), and park shape index (PSI) were significantly negatively correlated with the park LST. We also found that WAP, PP, and greenness (characterized by the normalized difference vegetation index (NDVI)) were three important factors that determined the park cooling island. However, the relationship between PA and the park cooling island was complex, as the results indicated that only parks larger than a threshold size (20 ha in our study) would provide a larger cooling effect with the increase in park size. In this case, increasing the NDVI of the parks by planting more vegetation would be a more sustainable and effective solution to form a stronger park cooling island.

Objective: To analyze the hot spot and frontier of traditional Chinese medicine treatment for primary immune thrombocytopenia with CiteSpace softwar for visualized analysis. Methods: The relevant literature about treatment for ITP through traditional Chinese medicine was retrieved from CNKI. The CiteSpace software was used to create visualization map for authors, institutions and keywords. Results: Through visualization analysis,121 authors and 36 institutions were included in the map. The main research hot spot is the clinical effect of traditional Chinese medicine and integrated traditional Chinese and Western medicine in the treatment for ITP. Conclusion: Ratio of research about traditional Chinese medicine treatment on ITP was relatively few. In addition, the cooperation and communication were also insufficient between teams and institutions. The research hot spot mostly focuses on clinical treatment, while theoretical research was very few. There is no deep investigation on treatment mechanism.

Multiple techniques were utilized to characterize the structure and morphology of the SnO2/reduced graphene oxide (rGO) composite, in which the composite was prepared by a facile one-pot microwave-assisted hydrothermal method. As a result, SnO2 nanoparticles with diameters of 3–5 nm were anchored uniformly on both sides of the rGO sheets. Meanwhile, a series of resistive-type gas sensors based on SnO2/rGO composite and pure SnO2 were fabricated and tested for analyzing the effects on introducing rGO. The results revealed that, the composite exhibited obviously enhanced gas sensing properties towards NO2 with high response, fast response and recovery speed, and good selectivity and reproducibility. At 75 °C, the response of the composite to 350 ppb NO2 was about 6.6 times of that to pure SnO2. In addition, the response and recovery time of the sensor was greatly reduced from 39.2/54.7 to 6.5/1 min, and the detecting limit of the sensor was even as low as 50 ppb. Provided with the enlarged surface area and local p-n heterojunctions, the synergistic effect of SnO2 nanoparticles and rGO contributed to the enhanced gas sensing properties of SnO2/rGO composite.

By considering the pre-buckling effect and in-plane constraint, an accurate nonlinear buckling analysis of a functionally graded porous graphene platelet reinforced composite cylindrical shells under axial compressive load is performed. The stability equation is established according to a unified shell theory including the classical thin shell theory and the high-order shear deformation theory. Three types of porosity distributions and graphene platelet reinforced patterns are considered, and the modified Halpin–Tsai model and rule of mixtures are employed to determine their effective material properties. Explicit expressions of buckling equations for clamped or simply supported boundary conditions are obtained by the Galerkin's method. Highly accurate critical buckling loads and analytical buckling mode shapes are obtained simultaneously. A comparison between theoretical prediction and experiment is presented to verify the present method and very good agreement is reported. The influences of material properties on the buckling behaviors are also extensively investigated. It is recommended that the symmetric dispersion pattern is the optimal material distributions for both graphene platelets and porous, and the largest possible weight fraction, specific surface area and average thickness of graphene platelets could induce a better anti-buckling performance for the nanocomposite shell.

Pharmaceutical cocrystals are a promising technology that can be used to improve the solubility of poor aqueous compounds. The objective of this study was to systematically investigate the solubility of myricetin (MYR) cocrystals, including their kinetic solubility, thermodynamic solubility, and intrinsic dissolution rate (IDR). The effects of pH, surfactant, ion concentration, and coformers on the cocrystal solubility were evaluated. Furthermore, single crystal structures of MYR, myricetin–isonicotinamide (MYR–INM) and myricetin–caffeine (MYR–CAF) cocrystals were analyzed to discuss the possible reasons for the enhancement of cocrystal solubility from the perspective of the spatial structure. The results indicated that the kinetic solubility of MYR cocrystals was modulated by pH and cocrystal coformer (CCF) ionization in buffer solution, while it primarily depended on the CCF solubility in pure water. In addition, the solubility of MYR cocrystals was increased in a concentration dependent fashion by the surfactant or ion concentration. The thermodynamic solubility of MYR–INM (1:3) cocrystals decreased with the increases of the pH value of the dissolution media. The IDR of MYR cocrystals was faster than that of MYR in the same medium and extremely fast in pH 4.5 buffer. The improved solubility of MYR cocrystals was probably related to the alternate arrangements of MYR and INM/CAF molecules and increased intermolecular distance. The present study provides some references to investigate the solubility behavior of pharmaceutical cocrystals., Graphical abstract The myricetin (MYR) cocrystals solubility was systematically elucidated by investigating its kinetic solubility, thermodynamic solubility, and intrinsic dissolution rate. The improved solubility of MYR cocrystals was probably related to the alternate arrangements of MYR and isonicotinamide/caffeine (INM/CAF) molecules and increased intermolecular distance.fx1

Exact solutions for thermo-electro-mechanical free vibration of a piezoelectric fiber-reinforced composite (PFRC) cylindrical shell is obtained under the framework of Hamiltonian mechanics. Two types of fiber reinforcement including the uniformly distributed in each ply and functionally graded in the thickness direction are taken into considered. Unlike the classical analytical treatment which relies on trial functions, the governing equations in the Hamiltonian form can be directly solved through a rigorous way. Free vibration of PFRC cylindrical shells is reduced into a symplectic eigenproblem which has five kinds of explicit eigenfunctions. Analytical frequency equations and vibration mode shapes are derived simultaneously. In numerical examples, a comparison study is performed to verify the validity of the proposed solution. A detailed discussion is presented to reveal the effects of key influencing factors on the expression of eigenfunctions. Some new results which can be used as benchmarks for the approximate approach are given also.

Axially compressed composite cylindrical shells can attain multiple bifurcation points in their post-buckling procedure because of the natural transverse deformation restraint provided by their geometry. In this paper, the post-buckling analysis of functionally graded (FG) multilayer graphene platelets reinforced composite (GPLRC) cylindrical shells under axial compression is carried out to investigate the stability of such shells. Rather than the critical buckling limit, the focus of the present study is to obtain convergence post-buckling response curves of axially compressed FG multilayer GPLRC cylindrical shells. By introducing a unified shell theory, the nonlinear large deflection governing equations for post-buckling of FG multilayer GPLRC cylindrical shells with wide range of thickness are established, which can be easily changed into three widely used shell theories. Load-shortening curves for both symmetric and asymmetric post-buckling modes are obtained by Galerkin's method. Numerical results illustrate that the present solutions agree well with the existing theoretical and experimental data. The effects of geometries and material properties on the post-buckling behaviours of FG multilayer GPLRC cylindrical shells are investigated. The differences in the three shell theories and their scopes are discussed also.

Gastric cancer (GC) is the third leading cause of cancer-related deaths worldwide. MicroRNAs (miRNAs) have been widely validated as potential biomarkers for cancer treatment and diagnosis. This paper intends to study the effect and specific mechanism of miR-574-3p/CUL2 axis in GC. The miR-574-3p expression in GC tissues and cell lines was analyzed by reverse transcription polymerase chain reaction (RT-PCR). GC cell (N87) proliferation, migration and invasion were determined by the Brdu assay and Transwell assay, respectively. The tumor xenotransplantation model was established in vivo to test the effect of miR-574-3p or Cullin 2 (CUL2) on tumor growth. The relationship between miR-574-3p and CUL2 was predicated by bioinformatic analysis and verified by dual-luciferase reporter assay and RIP experiment. The expression of CUL2, hypoxia-induced transcription factor-1α (HIF-1α) as well as E-cadherin, Snail and Vimentin was monitored by western blot and immunohistochemistry. miR-574-3p was overexpressed in GC tissues and cells. Forced upregulation of miR-574-3p enhanced proliferation, migration, invasion and epithelial-mesenchymal transition (EMT) of GC cells (N87), while downregulation of miR-574-3p resulted in reverse effects. Additionally, miR-574-3p promoted N87 cells growth and EMT in vivo. CUL2 was negatively regulated by miR-574-3p in N87 cells, and upregulation of CUL2 repressed the malignant behaviors of N87 cells. Moreover, CUL2 directly interacted with HIF-1α and suppressed HIF-1α expression both in vitro and in vivo. miR-574-3p targeted CUL2 to upregulate HIF-1α, thus facilitating the progression of GC.

The therapeutic efficacy of chemotherapy in many types of hematological malignancies and solid tumors is dramatically hindered by multidrug resistance (MDR). This work presents a combination strategy of pretreatment of MDA-MB-231/MDR1 cells with quercetin (QU) followed by doxorubicin (DOX) to overcome MDR, which can be delivered by mixed micelles composed of the reduction-sensitive hyaluronic acid-based conjugate and d-α-tocopheryl poly(ethylene glycol) 1000 succinate. The combination strategy can enhance the cytotoxicity of DOX on MDA-MB-231/MDR1 cells by increasing intracellular DOX accumulation and facilitating DOX-induced apoptosis. The probable MDR reversal mechanisms are that the pretreatment cells with QU-loaded mixed micelles downregulate P-glycoprotein expression to decrease DOX efflux as well as initiate mitochondria-dependent apoptotic pathways to accelerate DOX-induced apoptosis. In addition, this combination strategy can not only potentiate in vivo tumor-targeting efficiency but also enhance the antitumor effect in MDA-MB-231/MDR1-bearing nude mice without toxicity or side effects. This research suggests that the co-administration of natural compounds and chemotherapeutic drugs could be an effective strategy to overcome tumor MDR, which deserves further exploration.

The focus of this paper is on the analytical buckling solutions of piezoelectric cylindrical nanoshells under the combined compressive loads and external voltages. To capture the small-scale characteristics of the nanostructures, the constitutive equations with the coupled nonlocal and surface effects are adopted within the framework of Reddy's higher-order shell theory. The governing equations involving the displacements and induced piezoelectric field are solved by employing the separation of variables. The derived accurate solutions conclude that bucking critical stresses should go down rapidly while the nonlocal effects reach a certain level. With the enhancing surface effects, the stability of piezoelectric cylindrical nanoshells can be improved significantly. Meanwhile, the induced electric field also plays an important role in elevating the buckling critical stresses. For the nanoshells with remarkable nonlocal effects, boundary conditions, shell length and radius have little influence on the buckling solutions. The detailed effects of the boundary conditions, geometric parameters, material properties and applied voltages are discussed.

The urban heat island (UHI) effect has many adverse impacts on natural and social environments. A better understanding of how complex urban biophysical and social structures affect UHI is crucial to improve urban thermal environments. However, few studies have investigated the effects of 2D/3D urban morphology on land surface temperature (LST) and vertical air temperature simultaneously. Using LST data retrieved from Landsat 8 images and vertical temperatures at different heights collected from unmanned aerial vehicle (UAV) measurements, this study investigated the effects of 2D and 3D urban morphology on the 3D urban thermal environment among different urban function zones (UFZs) in the snow-climate city of Changchun, China. Our main findings are: (1) the average difference in vertical temperature between heights of 1.5 and 100 m was 1.78 °C and the temperature decreasing rate was 0.027 °C/m when the height was lower than 30 m, compared to 0.014 °C/m for 30–100 m. (2) Although 3D metrics had significant impact on LST, the relationships between the 2D metrics and LST were much stronger, accounting for 61% of the variations in LST. Additionally, the 2D composition metrics had stronger correlations with LST than the configuration metrics. The influence of 3D building metrics on LST was context-dependent for different UFZs. Increasing building height could reduce LST in residential UFZs but increase LST in industrial UFZs. (3) The effect of 2D urban morphology on the vertical temperature was stronger than that on the 3D ones when the height was lower than 30 m; however, opposite results were obtained when the height was greater than 30 m. The effects of 2D or 3D metrics on vertical temperature vary depending on whether the height is larger or smaller than a threshold, which is related to the characteristics of the building height. In general, 30 m appeared to be the threshold in our study. (4) The performances of models that used both 2D and 3D metrics to explain both LST and 3D thermal environments were better than those of models that used either 2D or 3D metrics alone, especially in UFZs such as residential areas.

Axial compressed cylindrical shell has a post-buckling equilibrium state far below the critical load of eigenvalue buckling, therefore the post-buckling analysis could provide a more reliable instability criterion for engineering design. In this paper, the post-buckling analysis of magneto-electro-elastic (MEE) composite cylindrical shells subjected to multi-field coupled loadings is performed. The nonlinear large deflection governing equations for MEE composite cylindrical shells are established based on the high-order shear deformation theory. The post-buckling equilibrium paths with mode-jumping phenomenon are obtained by the Galerkin’s method involving a set of newly defined displacement functions. A comparison study is presented to verify the accuracy of the present results and good agreements are achieved. The effects of geometrical parameters, material properties and multi-field coupled loadings on post-buckling behaviors of MEE composite cylindrical shells are discussed also.

An accurate nonlinear buckling model for functional graded multilayer hybrid composites cylindrical shells under combined loads is proposed. A two-steps micromechanical approach including Halpin-Tsai and Mori-Tanaka method is employed to obtain the effective material properties of hybrid composites. A unified shell theory including Donnell's shell theory, first-order shear deformation theory and high-order shear deformation theory are adopted to derive the governing buckling equations. The axisymmetric pre-buckling deformation is taken into consideration in the solution procedure. Highly accurate critical buckling loads and analytical buckling mode shapes are obtained by Galerkin's method. The accuracy of the present solutions is validated by comparing with results of existing literature and numerical simulations. Effects of influencing parameters of reinforcements and their interactions on the structural stability of the hybrid composites cylindrical shells are revealed. Keywords: Functionally graded material, Hybrid composite, Cylindrical shell, Buckling, Critical buckling load

In order to study the chemical corrosion and temperature coupling effect on the triaxial compression mechanical properties of white sandstone, first, the white sandstone is soaked in acidic, neutral, and alkaline solutions respectively in different temperatures, after that, triaxial compression tests were carried out on the treated white sandstone, then, the strength and deformation of white sandstone after coupling action are analyzed, finally, the chemical corrosion and temperature coupling mechanism is studied. The results show that: At the same temperature (below 100°C),the triaxial compressive strength of the specimens in acidic and alkaline environments is lower than that in neutral environments. In the same chemical (acid or alkali) environment, the triaxial compressive strength of the specimen decreases with the increase of temperature (below 100°C); In a neutral environment, with the increase of temperature (below 100°C),the triaxial compressive strength of the specimen decreases slowly and basically remains unchanged. Below 100°C, the damage of rock caused by temperature is small and can be ignored; Different chemical (acid or alkali) environment can degrade rock damage and reduce its triaxial compressive strength. Temperature mainly affects the rate of chemical reaction, which damages the rock and reduces its strength.

Industrial robot is a potential alternative of machining tool in some certain process due to its flexibility and large workspace. The traditional stiffness model of robot cannot explain the situation that stiffness exits difference in opposite directions. Aiming at optimizing the robot side milling process, a measured stiffness performance evaluation index is proposed in this paper. It is deduced and calculated through actual measured data, which overcomes the shortcoming of other indexes deduced from traditional stiffness model. Experimental case indicates that the new index proposed in useful in feed direction and tool-workpiece relative position optimization.

An accurate buckling analysis for piezoelectric fiber-reinforced composite (PFRC) cylindrical shells subjected to combined loads comprising compression, external voltage and thermal load is presented in this paper. Based on Reddy’s higher-order shear deformation theory, the governing equations for the coupled displacement field and induced piezoelectric field are established. Considering two different kinds of fiber-reinforced configurations, i.e. uniformly distributed (UD) and functionally graded (FG) reinforcements, the buckling solutions of perfect and imperfect PFRC cylindrical shells are obtained by applying separation of variables and Galerkin’s method. The influence of geometric parameters, piezoelectric effect, external electric voltage, temperature field and fibers distribution configurations on buckling characteristics and imperfection sensitivity are discussed in detail. The formulation system thus developed is suitable to other shell theories and to account for the coupled electro-magneto-thermo-elastic effects.