Pushing the Electrochemical Performance Limits of Polypyrrole Toward Stable Microelectronic Devices

Conducting polymers have achieved remarkable attentions owing to their exclusive characteristics,for instance,electrical conductivity,high ionic conductivity,visual transparency,and mechanical tractability.Surface and nanostructure engineering of conjugated conducting polymers offers an exceptional pathway to facilitate their implementation in a variety of scientific claims,comprising energy storage and production devices,flexible and wearable optoelectronic devices.A two-step tactic to assemble high-performance polypyrrole(PPy)-based microsupercapacitor(MSC)is utilized by transforming the current collectors to suppress structural pulverization and increase the adhesion of PPy,and then electrochemical co-deposition of PPy-CNT nanostructures on rGO@Au current collectors is performed.The resulting fine patterned MSC conveyed a high areal capacitance of 65.9 mF cm^(−2)(at a current density of 0.1 mA cm^(−2)),an exceptional cycling performance of retaining 79%capacitance after 10,000 charge/discharge cycles at 5 mA cm^(−2).Benefiting from the intermediate graphene,current collector free PPy-CNT@rGO flexible MSC is produced by a facile transfer method on a flexible substrate,which delivered an areal capacitance of 70.25 mF cm^(−2) at 0.1 mA cm^(−2) and retained 46%of the initial capacitance at a current density of 1.0 mA cm^(−2).The flexible MSC is utilized as a skin compatible capacitive micro-strain sensor with excellent electromechanochemical characteristics.

Interdigital MnO_(2)/PEDOT Alternating Stacked Microelectrodes for High-Performance On-Chip Microsupercapacitor and Humidity Sensing

For microelectronic devices,the on-chip microsupercapacitors with facile construction and high performance,are attracting researchers'prior consideration due to their high compatibility with modern microsystems.Herein,we proposed interchanging interdigital Au-/MnO_(2)/polyethylene dioxythiophene stacked microsupercapacitor based on a microfabrication process followed by successive electrochemical deposition.The stacked configuration of two pseudocapacitive active microelectrodes meritoriously leads to an enhanced contact area between MnO_(2)and the conductive and electroactive layer of polyethylene dioxythiophene,hence providing excellent electron transport and diffusion pathways of electrolyte ions,resulting in increased pseudocapacitance of MnO_(2)and polyethylene dioxythiophene.The stacked quasi-solid-state microsupercapacitors delivered the maximum specific capacitance of 43 mF cm^(-2)(211.9 F cm^(-3)),an energy density of 3.8μWh cm^(-2)(at a voltage window of 0.8 V)and 5.1μWh cm^(-2)(at a voltage window of 1.0 V)with excellent rate capability(96.6%at 2 mA cm^(-2))and cycling performance of 85.3%retention of initial capacitance after 10000 consecutive cycles at a current density of 5 mA cm^(-2),higher than those of ever reported polyethylene dioxythiophene and MnO_(2)-based planar microsupercapacitors.Benefiting from the favorable morphology,bilayer microsupercapacitor is utilized as a flexible humidity sensor with a response/relaxation time superior to those of some commercially available integrated microsensors.This strategy will be of significance in developing high-performance on-chip integrated microsupercapacitors/microsensors at low cost and environment-friendly routes.

From Acupoints to Mylohyoid: Revealing the Neural Circuitry Basis of Electroacupuncture for Dysphagia

Acupuncturea representative and historical treatment in traditional Chinese medicine(TCM),has been used to cure diseases for Chinese people in the past centuries.Since the late 1990s,acupuncture has been further accepted worldwide.The World Health Organization(WHO)proposed Clinical Research Specification for acupuncture in 1995 and the US Food and Drug Administration(FDA)approved acupuncture as a complementary and alternative therapy for various kinds of diseases in 1996,with clinical advantages such as convenience and effectiveness[1].Cumulative evidence has proved that acupuncture could produce different degrees of efficacy for treating various kinds of diseases(such as neuropathic pain,migraine,Parkinson's disease et al.)and alleviate symptoms[2-4].However,unlike its evidence-based efficacies.

《胸部恶性肿瘤围术期静脉血栓栓塞症预防中国专家共识（2018版）》解读之流行病学篇

静脉血栓栓塞症(venous thromboembolism,VTE)是胸部恶性肿瘤患者围术期较常见的一种并发症,一旦发生,不但影响患者预后,还将占用大量医疗资源,这正逐步引起我们的广泛重视。然而,我国胸外科对于VTE的认识起步较晚,认知度和重视度亦不够,且目前尚缺少针对围术期VTE预防的指南支持。基于目前我国胸外科对于VTE的认识及预防措施现状,中国胸外科静脉血栓栓塞研究协作组发布了国际首部《胸部恶性肿瘤围术期静脉血栓栓塞症预防中国专家共识(2018版)》。本文将对其中胸部恶性肿瘤患者围术期VTE的高危患者筛查进行解读,以便于更好地理解共识相关内容。

Effects of Pb on Rhizosphere Soil Enzyme Activity and Chemical Constituents of Achyranthes bidentata Blume

[Objectives]The purpose of this study was to investigate the effects of Pb on rhizosphere soil enzyme activity and chemical constituents of Achyranthes bidentata Blume.[Methods]A.bidentata Blume plants were cultivated in self-made polyvinyl chloride(PVC)pots.The soil was added with different levels of Pb(0,200,400,600,800 and 1000 mg/kg air-dried soil)to investigate the effects of Pb on dry mass,active ingredients(oleanolic acid and ecdysterone)and rhizosphere soil enzyme activity of A.bidentata Blume.[Results]The root dry mass of A.bidentata Blume cultivated in the soil with Pb level above 400 mg/kg significantly reduced.The Pb residues in the A.bidentata Blume.plants growing in the soil with Pb level below 400 mg/kg complied with national standard.The contents of oleanolic acid and ecdysterone in A.bidentata Blume growing in the soil with Pb level above 600 mg/kg declined significantly.At the Pb level of 1000 mg/kg,the activity of urease was inhibited significantly.The activity of phosphatase was inhibited in the presence of Pb in the soil.The activity of sucrase was activated in the soil with Pb level below 400 mg/kg,and was inhibited in the soil with Pb level above 400 mg/kg.[Conclusions]This study has important guiding significance for the reasonable selection of planting base for A.bidentata Blume and the guarantee of its yield and quality.

Platinum nickel alloy-MXene catalyst with inverse opal structure for enhanced hydrogen evolution in both acidic and alkaline solutions

The development of an efficient Pt-based electrocatalyst in acidic and alkaline electrolytes is of great significance to the field of electrocatalytic hydrogen evolution.Herein,we report a strategy for in situ growth of Pt_(3)Ni truncated octahedrons on Ti3C2Tx nanosheets and then obtain an ordered porous catalyst via a template method.Meanwhile,we use the finite element calculation to clarify the relationship between the component structure and performance and find that the performance of the spherical shell microstructure catalyst is higher than that of the disc structure catalyst,which is also verified by experiments.The experimental analysis shows that the ordered porous catalyst is conducive to enhancing electrocatalytic hydrogen evolution activity in acidic and alkaline electrolytes.In an acidic solution,the overpotential is 25 mV(10 mA·cm^(−2)),and the Tafel slope is 22.86 mV·dec−1.In an alkaline solution,the overpotential is 44.1 mV(10 mA·cm^(−2)),and the Tafel slope is 39.06 mV·dec−1.The synergistic coupling between Ti3C2Tx and Pt_(3)Ni nanoparticles improves the stability of the catalyst.The in situ growth strategy and design of microstructure with its correlation with catalytic performance represent critical steps toward the rational synthesis of catalysts with excellent catalytic activity.

Improvement of the activity and thermostability of l‑threonine aldolase from Pseudomonas putida via tailoring of the active sites lining the binding pocket

l-threonine aldolases catalyze the conversion of glycine and aldehydes to synthesizeβ-hydroxy-α-amino acids with unsatisfactory enzyme activity.Here,we expressed the l-threonine aldolase from Pseudomonas putida KT2440(l-PpTA)in Escherichia coli BL21(DE3)and improved the activity and thermostability by protein engineering.Five amino acid residues(Ser10,His89,Asp93,Arg177,and Arg321)located in the substrate-binding pocket were selected and for mutation.Eight mutants(D93A,D93G,D93M,D93F,D93S,D93Q,D93Y and D93H)with increased enzyme activity were identified and their k_(cat)/K_(M)values showed about 1-7-fold higher than wild-type.Among all the variants,D93H showed the highest catalytic efficiency with 2925 and 4515 s^(−1)mM^(−1)of k_(cat)/K_(M)values toward l-threonine and l-allo-threonine,respectively.In addition,circular dichroism spectrum exhibited that the melting temperature of D93H(54.2℃)was 5℃higher than wild-type(49.2℃).Molecular dynamics simulations illustrated that the D93H variant shortens the distance between the imidazole group of H93 and the hydroxyl group of substrate,which facilitated the proton extraction and promote the enzymatic reaction.This work affords a candidate for the synthesis ofβ-hydroxy-α-amino acids with improved catalytic efficiency and thermostability and provides structural insights into the l-TA family by protein engineering.

Improved computer-aided detection of pulmonary nodules via deep learning in the sinogram domain

Computer aided detection(CADe)of pulmonary nodules plays an important role in assisting radiologists’diagnosis and alleviating interpretation burden for lung cancer.Current CADe systems,aiming at simulating radiologists’examination procedure,are built upon computer tomography(CT)images with feature extraction for detection and diagnosis.Human visual perception in CT image is reconstructed from sinogram,which is the original raw data acquired from CT scanner.In this work,different from the conventional image based CADe system,we propose a novel sinogram based CADe system in which the full projection information is used to explore additional effective features of nodules in the sinogram domain.Facing the challenges of limited research in this concept and unknown effective features in the sinogram domain,we design a new CADe system that utilizes the self-learning power of the convolutional neural network to learn and extract effective features from sinogram.The proposed system was validated on 208 patient cases from the publicly available online Lung Image Database Consortium database,with each case having at least one juxtapleural nodule annotation.Experimental results demonstrated that our proposed method obtained a value of 0.91 of the area under the curve(AUC)of receiver operating characteristic based on sinogram alone,comparing to 0.89 based on CT image alone.Moreover,a combination of sinogram and CT image could further improve the value of AUC to 0.92.This study indicates that pulmonary nodule detection in the sinogram domain is feasible with deep learning.

A Tentative Discussion on How to Help Junior High School Students Improve Their Writing Skills Through Post-Reading Activities

The present situation of English writing in junior high schools includes the following aspects:first,students are weak in English writing because they lack vocabulary and do not use vocabulary appropriately;second,they often make grammar errors in writing;as a result,they do not obtain high scores in English writing;third,they form sentences based on their habit of thinking in their mother-tongue because of the influence of mother tongue transfer;in that case,Chinglish often appears in their compositions,and this is one of the main reasons they do not obtain high scores in English writing;finally,they do not arrange their compositions well,so most of their compositions are loosely organized.As reading and writing are designed as two separated parts in most English textbooks used in China,it is a challenge for teachers to design post-reading activities to integrate reading and writing because it is time-consuming.Based on the present situation of students’English writing and the teaching situation of English writing in junior high schools,this paper will discuss how to utilize post-reading activities to help students memorize vocabulary effectively,use vocabulary and grammar appropriately,avoid the influence of mother-tongue transfer,and build compact structures,so that they can improve their English writing skills.This discussion is based on the awareness of integrating reading with writing and making reading a supportive element of writing by utilizing post-reading activities.

The involvement of Slc7a11/xCT related iron accumulation on acupuncture intervention in 6-OHDA-induced Parkinson rat

Background:Acupuncture plays a critical role for the treatment of patients with Parkinson’s disease(PD),which is characterized by ferroptosis of dopaminergic neurons.It has been found that acupuncture can reduce iron accumulation.However,the mechanism of acupuncture therapy against PD by inhibiting ferroptosis remains unclear.Objective:To investigate the potential mechanism of acupuncture on alleviating ferroptosis in 6-OHDA-induced PD rats.Methods:Male Sprague-Dawley rats were randomly divided into sham group,acupuncture group,and PD model group,with the PD model induced by 6-OHDA.The motor function of the rats was tested by the rotation test and suspension test,respectively.Immunohistochemistry and iron staining were performed to analyze nerve damage,and the effect of acupuncture on the accumulation of iron in the substantia nigra(SN).RNA-seq analysis in the SN of rats were performed to discover ferroptosis-related genes.Differentially expressed genes(DEGs)resulted from the acupuncture treatment were identified and were used for Gene Ontology(GO)function,Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analyses.A protein–protein interaction(PPI)network was constructed,and alternative splicing(AS)analysis of the transcriptome was performed.Western blot was used to detect the protein level change of Slc7a11/xCT.Results:Rotation test and suspension test indicated a positive effect of acupuncture on body weight gain and limb function.Perl’s iron staining and ELISA test detected 6-OHDA induced iron accumulation in the SN and nerve damage,which was mitigated by acupuncture treatment.Acupuncture treatment brought about the differential expression of a total of 1088 genes in the SN of rats.GO and KEGG enrichment revealed that such DEGs were mainly associated with several key biological process(BP),cellular component(CC)and molecular function(MF)terms.These terms included collagen fibril organization,extracellular matrix organization,collagen trimer,extracellular matrix components,chemokine receptor binding and cargo receptor activity,etc.Additionally,the DEGs were found to be involved in pathways such as complement and coagulation.The PPI network of DEGs suggested a critical role of Slc7a11,which was further supported by an up-regulated Slc7a11/xCT protein level in the substantia nigra(SN)tissue of rats treated with acupuncture compared to their PD model counterparts(P=0.045).Conclusion:Acupuncture may prevent ferroptosis through Slc7a11/xCT as one of the targets in 6-OHDA-induced PD model and thereby could be promising for PD treatment.

Size and shape control of LiFePO4 nanocrystals for better lithium ion battery cathode materials

Lithium iron phosphate （LiFePO4） is a potential high efficiency cathode material for lithium ion batteries, but the low electronic conductivity and single diffusion channel for lithium ions require good particle size and shape control during the synthesis of this material. In this paper, six LiFePO4 nanocrystals with different size and shape have been successfully synthesized in ethylene glycol. The addition sequence Fe-PO4-Li helps to form LiFePO4 nanocrystals with mostly {010} faces exposed, and increasing the amount of LiOH leads to a decrease in particle size. The electrochemical performance of the six distinct LiFePO4 particles show that the most promising LiFePO4 nanocrystals either have predominant {010} face exposure or high specific area, with little iron（II） oxidation.

Flexible SnS nanobelts： Facile synthesis, formation mechanism and application in Li-ion batteries

[020]-oriented tin sulfide nanobelts with a length/thickness ratio of 100 have been synthesized by a facile hydrothermal method without any surfactants, and the nanobelts have shown good strain-accommodating properties as well as good electrochemical performance as the anode for Li-ion batteries. The formation of the nanobelts results from a precipitation-dissolution-transformation mechanism, and the [020] oriented growth can be ascribed to the {010} facet family having the lowest atomic density. In particular, SnS shows clear Li-Sn alloying/de-alloying reversible reactions in the potential range 0.1-1.0 V. Based on galvanostatic measurements and electrochemical impedance spectroscopy, SnS nanobelts have shown impressive rate performance. The post-cycled SnS nanobelts were completely transformed into metallic tin, and preserved the one-dimensional structure due to their flexibility which accommodates the large volumetric expansion.

A perspective on off-policy evaluation in reinforcement learning

The goal of reinforcement learning (RL) is to build an autonomous agent that takes a sequence of actions to maximize a utility function by interacting with an external, unknown environment. It is a very general learning paradigm that can model a wide range of problems, such as games, robotics, autonomous driving, humancomputer interactions, recommendation, healthcare, and many others. In recent years, powered by advances in deep learning and computing power, RL has seen great successes, with AlphaGo/AlphaZero as a prominent example. Such impressive outcomes have sparked fast growing interests in using RL to solve real-life problems.

Heterologous expression of bovine lactoferrin C‑lobe in Bacillus subtilis and comparison of its antibacterial activity with N‑lobe

The natural concentration of bovine lactoferrin C-lobe is low and its separation by proteolytic enzyme digestion is difcult.Here,we expressed the codon-optimized fragment of C-lobe on plasmid pMA0911 with the P_(veg) promoter in Bacillus subtilis 168 at 20℃.The yield was 7.5 mg/L,and 90.6%purity was achieved using ammonium sulfate precipitation,Ni–NTA and molecular exclusion.The C-lobe at 10 mg/mL completely inhibited cell growth of Escherichia coli JM109(DE3)and Pseudomonas aeruginosa CGMCC 1.6740,and 48.4%of growth of Staphylococcus aureus CGMCC 1.282,the result is similar to that of 200 ng/mL N-lobe.The minimum inhibitory concentrations of C-lobe were 4,8 and 16 mg/mL,while those of N-lobe were 128,256 and 512μg/mL for E.coli,P.aeruginosa and S.aureus,respectively.This is the frst report on bovine lactoferrin C-lobe expression and the comparative resistance of the recombinant N-and C-lobes in a food-safe strain of B.subtilis.Our fndings ofer the potential to study the structure–function relationship of the N-and C-lobes recombinantly produced in the same host.

Acupuncture for treating adolescent depression:Study protocol for a randomized controlled trial

The prevalence of depression among adolescents has been significantly increasing in recent years.However,current antidepressants for adolescents have limited safety and efficacy.Acupuncture has been shown to be effective in treating depression in adults,but there is a lack of high-quality evidence for its effect on the treatment of adolescent depression,and the underlying mechanism is still unclear.Therefore,we designed a randomized controlled trial to explore the effectiveness and the therapeutic mechanisms of acupuncture on adolescent depression.This study will be designed as a multi-center,sham and randomized controlled clinical trial.For this purpose,a total of 96 adolescent depression patients diagnosed with moderate and severe depression will be randomly divided into the manual acupuncture group and the sham one,respectively.The two groups received acupuncture treatment 3 times a week for a total course lasting 4 weeks.All patients will be assessed according to the primary outcomes including Beck Depression Inventory-II(BDI-II),Hamilton Depression Rating Scale(HAMD-24)and Zung self-rating depression scale(SDS)at baseline,week 2,4 and 8.Additionally,the secondary outcomes will be assessed at baseline and week 4,which includes intestinal flora structure,fecal short chain fatty acids(SCFAs)content and serum serotonin(5-HT)level.This study is the first randomized trial of acupuncture treatment of adolescent depression.

Pseudomonas putida KT2440低特异性L-苏氨酸醛缩酶的表达、酶学性质及温度稳定性提高

【目的】从Pseudomonas putida KT2440基因组中,钓取低特异性L-苏氨酸醛缩酶基因(lta E),构建重组大肠杆菌。研究目标酶的酶学性质,和关键氨基酸位点突变对酶活和温度稳定性的影响。【方法】以P. putida KT2440基因组DNA为模板,PCR扩增出lta E基因,构建重组表达质粒p ET28a-KT2440并转化Escherichia coli BL21 (DE3),获得重组菌E. coli BL21 (DE3)/p ET-KT2440,利用Ni2+柱亲和层析纯化低特异性L-苏氨酸醛缩酶(LTA),对关键氨基酸位点Thr206和Lys207实施定点突变。【结果】SDS-PAGE结果表明LTA在大肠杆菌中获得高效表达,分子量为40k Da左右,与理论值大小相符。Ni2+柱亲和层析纯化LTA,获得单一条带。利用双酶耦联法测得LTA酶活为5577.3U/mg,最适反应温度为50°C,最适p H为8.0。在温度低于45°C,p H 5.0-9.0时,重组酶较稳定。LTA酶的Km和kcat值为23.95 mmol/L和19216.6 s–1。Mg2+、Ca2+金属离子对LTA有明显的促进作用,而Ni2+、Cu2+、Zn2+、Fe2+等对酶有明显的抑制作用。该酶在叔丁基甲基醚溶剂中具有良好的耐受性,在叔丁基甲基醚中保存1h后仍保留90%以上的酶活。Thr206Ser突变明显提高了酶对温度的稳定性。Lys207对酶催化功能是必需的,该位点突变对酶活都是致死的。【结论】克隆并表达P. putida KT2440的LTA酶,研究了酶学性质,通过定点改造提高了酶的温度稳定性,筛选获得一种酶耐受性好的有机溶剂,为LTA酶在有机溶剂中高效稳定催化β-羟基-α-氨基酸奠定了较坚实的研究基础。

Multipath affinage stacked-hourglass networks for human pose estimation

Recently,stacked hourglass network has shown outstanding performance in human pose estimation.However,repeated bottom-up and top-down stride convolution operations in deep convolutional neural networks lead to a significant decrease in the initial image resolution.In order to address this problem,we propose to incorporate affinage module and residual attention module into stacked hourglass network for human pose estimation.This paper introduces a novel network architecture to replace the stacked hourglass network of up-sampling operation for getting high-resolution features.We refer to the architecture as an affinage module which is critical to improve the performance of the stacked hourglass network.Additionally,we also propose a novel residual attention module to increase the supervision of up-sample process.The effectiveness of the introduced module is evaluated on standard benchmarks.Various experimental results demonstrated that our method can achieve more accurate and more robust human pose estimation results in images with complex background.

Characterization and pilot functional study of a root-specific MYB transcription factor of Arabidopsis

An MYB transcription factor (AtMYB305) of Arabidopsis was structurally characterized. The biochemical activity of the protein was tested and its in vivo function was preliminarily analyzed. AtMYB305 contains two imperfect repeats (R2, R3) in its DNA binding domain. Gel mobility shift assay demonstrated that GST-AtMYB305 fusion pro-tein bound specifically to the DNA fragment that included a consensus MYB recognition sequence (TAACTG). Overex-pression of AtMYB305 in the fission yeast caused the forma-tion of elongated cells with one condensed nucleus. Semi-quantitative RT-PCR analysis revealed that AtMYB305 was expressed specifically in the roots of Arabidopsis.

Effect of UTRs from TMV-RNA on the expression of foreign gene in transgenic plants

To investigate the effects of 5’and 3’ untranslated region (UTR) from tobacco mosaicvirus (TMV) on expression of foreign genes, four plant-expression vectors pBG437, pBG438, pBG440 and pBG440ANOS containing expression cassettes of GUS-NOS; Ω-GUS-NOS, Ω-GUS-3’ UTR-NOS and Ω-GUS-3’ UTR downstream of CaMV 35S promoter with double enhancer sequences respectively have been constructed. Results from a large number of transgenic tobacco plants show that the GUS activity of pBG440 transformed plants is the highest, being 5-fold that of pBG437 and 1.6-fold that of pBG438. Similar results have been obtained in transient expression by injection of Agrobacterium tumefaciens harbouring these constructs into N. benthamiana leaves. These results obtained at the whole plant level confirm the conclusion drawn from the transient expression studies in protoplast system that TMV- Ω fragment can be a translation enhancer and the 3’ UTR has a coordinate effect with ft fragment to enhance foreign gene expression, but

Controllable printing of large-scale compact perovskite films for flexible photodetectors

Perovskite materials are promising candidates for the next generation of wearable optoelectronics.However,due to uncontrolled crystallization and the natural brittle property of crystals,it remains a great challenge to fabricate large-scale compact and tough perovskite film.Here we report a facile method to print large-scale perovskite films with high quality for flexible photodetectors.By introducing a soluble polyethylene oxide(PEO)layer during the inkjet printing process,the nucleation and crystal growth of perovskite is well controlled.Perovskite films can be easily printed in large scale and patterned in high resolution.Moreover,this method can be extended to various kinds of perovskite materials,such as MAPbb(MA=methylammonium),MA_(3)Sb_(2)l_(9),and(BA)_(2)PbBr_(4)(BA=benzylammonium).The printed perovskite films show high quality and excellent mechanical performance.The photodetectors based on the MAPbBr3 perovskite films show a responsivity up to -1,036 mAA/V and maintain over 96.8%of the initial photocurrent after 15,000 consecutive bending cycles.This strategy provides a facile approach to prepare large-scale flexible perovskite films.It opens up new opportunities for the fabrication of diverse wearable optoelectronic devices.