An Analysis of the Evolution of Online Public Opinion on Public Health Emergencies by Combining CNN-BiLSTM + Attention and LDA

In this paper, the Foxconn epidemic event in Zhengzhou was taken as an example to analyze the evolution of online public opinion on public health emergencies. In order to improve the performance of online public opinion analysis, based on the life cycle theory and LDA theory, the emotional changes of Internet users in four stages of the Foxconn incident centered on the evolution of inscription were divided. The emotions of netizen speech at different stages are analyzed based on CNN-BiLSTM + Attention model, which uses Convolutional Neural Network (CNN) to extract local features. Bi-directional Long Short-Term Memory (BiLSTM) is used to efficiently extract contextual semantic features and long distance dependencies, and then combined with attention mechanism to add emotional features. Finally, Softmax classifier realizes text emotion prediction. The experimental results show that: compared with TextCNN, BiLSTM, BiLSTM + Attenion, CNN-BiLSTM model, the emotion classification model has better effects in the accuracy rate, accuracy rate, recall rate and F value. By analyzing the emotional distribution and evolution trend of public opinion under “text topic”, the paper accurately deconstructs the development characteristics of public opinion in public health emergencies, in order to provide reference for relevant departments to deal with public opinion in public health emergencies. .

pH-sensitive micelles self-assembled from star-shaped TPGS copolymers with ortho ester linkages for enhanced MDR reversal and chemotherapy

TPGS approved by FDA can be used as a P-gp inhibitor to effectively reverse multi-drug resistance(MDR)and as an anticancer agent for synergistic antitumor effects.However,the comparatively high critical micelle concentration(CMC),low drug loading(DL)and poor tumor target limit its further clinical application.To overcome these drawbacks,the pH-sensitive star-shaped TPGS copolymers were successfully constructed via using pentaerythritol as the initial materials,ortho esters as the pH-triggered linkages and TPGS active-ester as the terminated MDR material.The amphiphilic star-shaped TPGS copolymers could self-assemble into free and doxorubicin(DOX)-loaded micelles at neutral aqueous solutions.The micelles exhibited the lower CMC(8.2×10^(−5) mg/ml),higher DL(10.8%)and long-term storage and circulation stability,and showed enhanced cellular uptake,apoptosis,cytotoxicity,and growth inhibition for in vitro MCF-7/ADR and/or MCF-7/ADR multicellular spheroids and in vivo MCF-7/ADR tumors via efficiently targeted drug release at tumoral intracellular pH(5.0),MDR reversal of TPGS,and synergistic effect of DOX and TPGS.Therefore,the pH-sensitive micelles self-assembled from star-shaped TPGS copolymers with ortho ester linkages are potentially useful to clinically transform for enhanced MDR cancer treatment.

Self-assembly of DNA molecules at bio-interfaces and their emerging applications for biomedicines

Interfacial assembly has been intensively investigated in fabricating biomaterials and nanodevices for various applications.Recently,due to the precise sequence programmability,unique molecular recognition ability,and good biocompatibility,deoxyribonucleic acid(DNA)has been explored as superior building blocks to assemble at bio-interface for manipulating biological entities.To the best of our knowledge,the advances in this area have not been systematically summarized.To provide an overview of the area,in this review,the recently developed DNA assembly strategies on bio-interfaces were well summarized,and their representative works are exampled to illustrate how to rationally and elaborately design DNA molecules to realize functional integration and emerging of novel biological functionalities with high controllability and programmability.Furthermore,the biomedical applications of DNA assembly at bio-interface are categorially elaborated.The fascinating and unique advantages of DNA assembly systems are fully discussed in the exemplified applications to show the distinguished perspective of DNA in the future development.At the end of this review,the current limitations and challenges in applications and potential improvement strategies for DNA assembly at bio-interface are fully discussed.The future development direction is deliberated.We envision that this review will help scientists in the interdisciplinary fields gain a more comprehensive understanding of the DNA assembly at bio-interface,and therefore jointly promote the advances in this field.

High-definition colorful perovskite narrowband photodetector array enabled by laser-direct-writing

Narrowband photodetectors as specific spectral sensing pixels have drawn intense attention in multispectral detection due to their distinct characteristic of filter-free spectrum discrimination,in which the emerging halide lead perovskites witness a booming development in their performance and wavelength-selectivity from blue to near-infrared light.However,the challenge in integrating perovskite narrowband photodetectors on one chip imposes an impediment on practical application.In this work,the combination of laser-direct-writing and ion exchange is proposed as an efficient way to fabricate high-definition colorful sensing array with perovskite narrowband photodetector unit as pixel.Under laser irradiation,the photolysis of halocarbon solvent(CHCl_(3),CH_(3)CH_(2)I,etc)releases the halide ions,which brings the ion exchange and gives rise to slow-varying bandgap in single perovskite photoactive film.This ion exchange can be controlled via laser irradiation time and focus point,thus enabling precisely engineerable bandgap.By optimizing the process,it is successfully applied to develop patterned perovskite narrow blue and green photodetectors array with a high-definition of~53 ppi.We believe this result will make a great step forward to integrate multifunctional perovskite devices on one chip,which will pave the way for perovskite optoelectronic device to the commercial application.

低维结构策略构筑基于钙钛矿纳米片/氧化锌纳米线的柔性宽光谱探测器（英文）

柔性光电探测器具有轻便、易携带和优异的大面积兼容性等特点,在下一代光电子器件领域具有巨大的应用潜力.柔性光电探测器面临的主要挑战是在反复弯曲、拉伸、折叠等形变状态下难以保持优异的性能.本文通过低维度结构策略构筑了基于CsPbBr3纳米片和ZnO纳米线的柔性光电探测器.得益于一维纳米线和二维纳米片的高柔性,所构筑的光电探测器在各种应力下表现出优异的工作稳定性.例如,在弯曲1000次之后,器件的性能没有明显变化.此外,由于ZnO和CsPbBr3自身的光吸收特性,所构筑的柔性光电探测器展现出宽光谱光电响应能力(涵盖紫外和可见波段).在紫外和可见区域的峰值响应度分别为3.10和0.97 A W^-1,其相应的探测率分别为5.57×10^12和1.71×10^12Jones.本文针对柔性、高性能集成光电探测器提出的维度构筑策略,在未来智能、可穿戴光电子器件领域有着巨大的应用前景.

Self-assembly of artificial architectures in living cells-design and applications

Self-assembly exists widely in natural living system and artificial synthetic material system.Administration of self-assemblies of artificial architectures in living cells can be used to explore the molecular physicochemical fundamentals and operating mechanisms of living system,and consequently promote the development of biomedicine.In order to mimic naturally occurring self-assemblies and realize controllable functions,great efforts have been devoted to constructing dynamic assembly of artificial architectures in living cells by responding to intracellular specific stimuli,which can be used to regulate morphology,behaviors and fate of living cells.This review highlights the recent progress on artificial self-assembly in living cells.The molecular fundamentals and characteristics of intracellular environment that can induce the self-assembly of artificial architectures are introduced,and the representative work on dynamic artificial self-assembly in living cells is sketched chronologically.Moreover,intracellular stimuli-mediated pathways of artificial assembly in living cells are categorized,biological effects caused by intracellular self-assembly are summarized,and biomedical applications focusing on therapy and imaging are described.In the end,the perspective and challenges of artificial self-assembly in living cells are fully discussed.It is believed that the grand advances on artificial self-assembly in living cells will contribute to elaborating the molecular mechanisms in cells,and further promoting the biologically and medically-related applications in the future.

Efficient recovery and enrichment of rare earth elements by a continuous flow micro-extraction system

The excessive exploitation of rare earth elements(REEs)has caused major losses of non-renewable resources and damage to the ecosystem.The processes of mining and smelting produce massive amounts of wastewater with low concentrations of REEs.Consequently,the enrichment and recovery of low-concentration REEs from wastewater has significant economic and environmental value.For this purpose,operation under large phase ratios(the flow rate ratio between the aqueous phase and extractant)is more desirable and economically viable.However,the traditional REE extraction process suffers from the uneven dispersion of the extractant and the difficulty of phase separation,which leads to long extraction times and large consumption of extractants.Hence,there is an urgent need to develop a green and efficient technique to extract low concentrations of REEs from wastewater.In this work,a droplet-based microfluidic technique was used to continuously extract and recover low-concentration REEs at large phase ratios.Snowman-shaped magnetic Janus nanoparticles were added to the continuous phase as emulifiers to failitate uniform extractant dispersion and rapid phase separation.Several key factors affecting the extraction efficiency,including pH,residence time,and the amount of added Janus nanoparticles,were systematically investigated.Compared to batch extraction,droplet-based microfluidic extraction with the addition of Janus nanoparticles showed the advantages of a large speific surface area and fast phase separation during extraction.Meanwhile,the Janus nanoparticles exhibited good emulsification performance after three extraction cycles,In summary,the Janus nanoparticle-stabilized droplet generated by microfluidic methods provides a feasible path for the efficient enrichment and recovery of low-concentration REEs.