New Nonlinear Systems Admitting Virasoro-Type Symmetry Algebra and Group-Invariant Solutions

With the aid of symbolic computation by Maple, we extend the application of Virasoro-type symmetry prolongation method to coupled systems with two-component nonlinear equations. New nonlinear systems admitting infinitely dimensional centerless Virasoro-type symmetry algebra are constructed. Taking one of them as an example, we present some group-invariant solutions to one of the new model systems

Few-Shot Semantic Parsing for New Predicates

In this work, we investigate the problems of semantic parsing in a few-shot learning setting. In this setting, we are provided with utterance-logical form pairs per new predicate. The state-of-the-art neural semantic parsers achieve less than 25% accuracy on benchmark datasets when k= 1. To tackle this problem, we proposed to i) apply a designated meta-learning method to train the model; ii) regularize attention scores with alignment statistics; iii) apply a smoothing technique in pre-training. As a result, our method consistently outperforms all the baselines in both one and two-shot settings.Comment: Accepted to EACL 202

Relationships Between Perceived Usefulness and Fitness Wearable Technology User Adoption Mediated by Culture, Gender, and COVID-19: A Meta-Analysis

With COVID-19 raging and individuals exercising at home, the adoption of fitness wearable technology (FWT) that help people monitor their physical state has become a pressing matter. Here, we try to bridge the gap that no researcher has examined the link between perceived usefulness (PU) and FWT adoption by using meta-analysis to comprehend the detailed numerical values and moderating factors affecting the relationship. A total of 24 articles with 7180 re-pendants were investigated from January 1, 2015 to March 1, 2022 A.D, producing significant results as follows: (1) There is publication bias in relevant research, and sensitivity analysis suggests that PU influences FWT adoption positively; (2) Subgroup test and regression analysis suggested that cultural background, gender, and COVID-19 can deepen this relationship to varying degrees. More precisely, female (r=0.669) have a greater impact on FWT adoption than men (r=0.658). In addition, users in other countries (r=0.670) are more concerned about PU than Chinese users (r=0.658). Regression analysis showed that after the COVID-19 outbreak, the coefficient (r=0.762) of PU on FWT adoption increased significantly, indicating that people need FWT-assisted exercise to understand and maintain their own physical fitness. The research opens up new ideas for different governments and scholars to promote mass fitness and public health during the COVID-19, providing a reference for the scientific research and development of PU and marketing promotion of the related enterprises’ FWT

microRNA-29a functions as a tumor suppressor in nasopharyngeal carcinoma 5-8F cells through targeting VEGF

Objective(s): microRNA-29 (miR-29) family miRNAs have been mentioned as tumor suppressive genes in several human cancers. The purpose of this study was to investigate the function of miR-29a in nasopharyngeal carcinoma (NPC) cells. Materials and Methods: Human NPC cell line 5-8F was transfected with mimic, inhibitor or scrambled controls specific for miR-29a. Subsequently, cell viability, migration, apoptosis and expression changes of VEGF were assessed by trypan blue staining, MTT assay, transwell assay, flow cytometry, Western blot and RT-qPCR. TargetScan online database was used to predict the targets of miR-29a, and luciferase reporter assay was carried out for testing the targeting relationship between VEGF and miR-29a. Western blot analysis was performed to determine the expression changes of core proteins in PI3K/AKT and JAK/STAT pathways. Results: Overexpression of miR-29a suppressed 5-8F cells viability and relative migration, but increased apoptotic cell rate. Consistently, Bcl-2 was downregulated, Bax was upregulated, and caspase-3 and -9 were cleaved by miR-29a overexpression. VEGF was a target gene of miR-29a. Besides, VEGF silence exerted similar effects like miR-29a, as the viability and migration were repressed and apoptosis was induced. Finally, we found that PI3K/AKT and JAK/STAT pathways were deactivated by miR-29a or VEGF silence. Conclusion: These findings highlighted the tumor suppressive effects of miR-29a on NPC cells, as its overexpression inhibited 5-8F cells viability, migration, and induced apoptosis. miR-29a exerted tumor suppressive functions might be via targeting VEGF and deactivating PI3K/AKT and JAK/STAT pathways

Adsorption equilibrium, isotherm, kinetics, and thermodynamic of modified bentonite for removing Rhodamine B

Anionic and cationic surfactant modified sodium bentonite (Na-Bt) has been prepared by the cationic surfactant cetyltrimethyl ammonium bromide (CTAB) and the anionic surfactant sodium dodecyl benzene sulfonate (SDBS) to sodium bentonite, respectively. The properties of the modified samples are characterized by XRD, SEM, BET and FT-IR. The results of characterization shown that the cationic surfactant had changed the structure and properties of natural sodium bentonite, which proved that surfactants had been successfully implanted into sodium bentonite. But anionic surfactant had no change, this manifested SDBS didn’t insert the layers of bentonite. In addition, adsorption experiments of Rhodamine B (RhB) proved that the modified sodium bentonite adsorption performance is greatly improved. The adsorption experiments also indicated that CTAB-bentonite had the largest adsorption capacity compared with SDBS-bentonite due to the formation of a highly effective partition medium by cationic surfactant micelle. The adsorption data of RhB is analyzed with the isothermal model, thermodynamics and kinetics. Overall, this study provided high-efficiency method for the removal RhB by the surfactant modified bentonite

Fast growth of monolayer organic 2D crystals and their application in organic transistors

Growth of monolayer 2D organic crystal has been an interesting topic in recent years owing to their promising properties. However, it is still a tough challenge to obtain the 2D organic crystal with precise thickness control and uniform morphology. Herein, we reported the fabrication of 2D crystals of alkane molecules C44H90 with only monolayer thickness and tunable size through the simple dip-coating process. Benefitted from the low solubility of the C44H90 and the isotropic Van der Waals interaction, quadrilateral-shape monolayer 2D crystals with size from several micrometers to nearly hundreds of micrometers can be achieved in the dip-coating process. Utilized the X-ray diffraction and high resolution atomic force microscopy, we obtained the clear packing mode of these monolayer crystals. In addition, these smooth 2D crystals show promising application in the thin film transistors by acting as a molecular template layer. It leads to an increment of about one magnitude on the charge mobility owing to the decreasing of both morphology defects and interface traps.</p

The kinetic frictional shear stress of ZnO nanowires on graphite and mica substrates

The frictional shear stress between a nanostructure and a smooth substrate plays a crucial role in the development of nanodevices; however, it is extremely difficult to measure. In this work, the kinetic frictional shear stress of hexagonal ZnO nanowires on graphite and mica substrates was measured in an ambient atmosphere by optical microscope based nanomanipulation. Both substrates have similar surface roughness values of sub-angstrom-scale and interfacial adhesion energies with ZnO nanowires. Yet, a kinetic frictional shear stress of 0.51 MPa was obtained for the ZnO-graphite system, significantly lower than that of 5.1 MPa for the ZnO-mica system. The results demonstrate that the kinetic friction at a perfectly smooth contact interface may not be controlled by the adhesion, whilst being commonly referred to as adhesive friction or adhesion-dominated fiction. Similar to the combining equations for adhesion, we propose two empirical combining equations to estimate the frictional shear stress between two smooth surfaces using results more simply obtained from a reference surface. The validity of the equations is supported by our experimental results and recently published data for atomically smooth interface systems obtained under the similar environmental conditions

Adsorption equilibrium, isotherm, kinetics, and thermodynamic of modified bentonite for removing Rhodamine B

116-125Anionic and cationic surfactant modified sodium bentonite (Na-Bt) has been prepared by the cationic surfactant cetyltrimethyl ammonium bromide (CTAB) and the anionic surfactant sodium dodecyl benzene sulfonate (SDBS) to sodium bentonite, respectively. The properties of the modified samples are characterized by XRD, SEM, BET and FT-IR. The results of characterization shown that the cationic surfactant had changed the structure and properties of natural sodium bentonite, which proved that surfactants had been successfully implanted into sodium bentonite. But anionic surfactant had no change, this manifested SDBS didn&rsquo;t insert the layers of bentonite. In addition, adsorption experiments of Rhodamine B (RhB) proved that the modified sodium bentonite adsorption performance is greatly improved. The adsorption experiments also indicated that CTAB-bentonite had the largest adsorption capacity compared with SDBS-bentonite due to the formation of a highly effective partition medium by cationic surfactant micelle. The adsorption data of RhB is analyzed with the isothermal model, thermodynamics and kinetics. Overall, this study provided high-efficiency method for the removal RhB by the surfactant modified bentonite