CuPc/FeNC双组分催化剂协同催化硝酸盐转化为氨

氨(NH_(3))作为重要的化学品和能源储存介质,需求量与日俱增.本文旨在通过电化学硝酸根还原反应(NO_(3)^(−)RR),将NO_(3)^(−)转化为NH3,不仅解决了NO_(3)^(−)引起的环境污染问题,又可以满足对NH_(3)的迫切需求.然而,NO_(3)^(−)RR涉及多个电子和质子转移过程,其中,NO_(2)^(−)是NO_(3)^(−)活化转化和深度还原合成NH_(3)的重要中间体.酞菁铜(CuPc)能够高效地活化转化NO_(3)^(−)为NO_(2)^(−),但在低过电位时无法有效地将NO2−还原为NH3,难以获得较高的氨法拉第效率(FENH3)和分电流密度.而氮配位的铁单原子催化剂(FeNC)则有较好的NO_(2)^(−)吸附活化特性.因此,利用双组分催化剂之间的协同作用以实现高效NO_(3)^(−)RR的活性和选择性是本文的主要研究思路.本文设计了CuPc/FeNC串联催化剂,利用CuPc和FeNC对NO_(3)^(−)和NO_(2)^(−)的吸附活化能力的差异,实现了高效的协同催化转化.X射线衍射、高角环形暗场扫描透射电镜、X射线光电子能谱及X射线吸收谱结果表明,FeNC催化剂中Fe原子均匀分布于ZIF-8热解后的基底.通过将FeNC和CuPc负载于气体扩散电极,在流动电解池中完成NO_(3)^(−)RR.CuPc/FeNC催化剂在较低电势区间中能够实现接近100%的NH3法拉第效率,同时在−0.57 V vs.RHE时达到273 mA cm–2的NH3分电流密度,并且在整个电势范围内有效地抑制了NO_(2)^(–)聚集.与单组分催化剂CuPc和FeNC对比结果表明,在−0.53 V vs.RHE时,CuPc/FeNC催化剂表现出较高的FE(NH_(3))/FE(NO_(2)^(−))比值,是CuPc催化剂的50倍;同时CuPc/FeNC催化剂上NH3分电流密度是FeNC催化剂的1.5倍.进一步研究了NO_(3)^(–)RR中的串联反应机制,其中FeNC催化剂表现出较高的NO_(2)^(–)RR活性,并且有效抑制了析氢反应.此外,CuPc/FeNC催化剂和FeNC催化剂在NO_(2)^(−)RR中表现出类似的NH3分电流密度,这表明在NO_(3)^(−)RR中,CuPc/FeNC催化剂性能的提高来源于FeNC位点能够进一步还原CuPc位点产生的NO_(2)^(–).理论计算结果表明,FeNC比CuPc表现出更强的NO_(2)^(–)吸附活化能力,说明NO_(2)^(−)在FeNC上更容易进行加氢还原.NO_(3)^(−)RR反应全路径分析结果表明,对于^(*)NO_(3)还原到*NO2过程,CuPc相对于FeNC位点具有明显降低的反应自由能,说明CuPc有利于NO_(2)^(−)的生成;而FeNC位点在后续的^(*)NO_(2)还原合成^(*)NH_(3)过程中具有更低的反应自由能,这与实验结果一致.一系列非原位和原位表征证明了CuPc催化剂在高电位下存在少量金属颗粒析出,与CuPc催化剂在高电位下NH_(3)分电流密度快速增加结果一致.综上,本工作中CuPc和FeNC催化剂之间的协同作用弥补了各自的不足,通过串联反应机制,在低过电位下有效增加了NH_(3)的法拉第效率和电流密度,实现了高效的协同催化转化,为设计和合成高效催化剂提供了新思路.

Microstructure and mechanical properties stability of pre-hardening treatment in Al-Cu alloys for pre-hardening forming process

The stability of the microstructure and mechanical properties of the pre-hardened sheets during the pre-hardening forming(PHF)process directly determines the quality of the formed components.The microstructure stability of the pre-hardened sheets was in-vestigated by differential scanning calorimetry(DSC),transmission electron microscopy(TEM),and small angle X-ray scattering(SAXS),while the mechanical properties and formability were analyzed through uniaxial tensile tests and formability tests.The results in-dicate that the mechanical properties of the pre-hardened alloys exhibited negligible changes after experiencing 1-month natural aging(NA).The deviations of ultimate tensile strength(UTS),yield strength(YS),and sheet formability(Erichsen value)are all less than 2%.Also,after different NA time(from 48 h to 1 month)is applied to alloys before pre-hardening treatment,the pre-hardened alloys possess stable microstructure and mechanical properties as well.Interestingly,with the extension of NA time before pre-hardening treatment from 48 h to 1 month,the contribution of NA to the pre-hardening treatment is limited.Only a yield strength increment of 20 MPa is achieved,with no loss in elongation.The limited enhancement is mainly attributed to the fact that only a limited number of clusters are transformed into Guinier-Preston(GP)zones at the early stage of pre-hardening treatment,and the formation ofθ''phase inhibits the nucleation and growth of GP zones as the precipitated phase evolves.

PbrARF4 contributes to calyx shedding of fruitlets in ‘Dangshan Suli’ pear by partly regulating the expression of abscission genes

Fruitlet calyx shedding in pear plants is apparently regulated via numerous pathways that involve both environmental triggers and phytohormones cues such as auxin. In this study, we found at 10 days after full bloom (DAFB) higher levels of indoleacetic acid (IAA) and tryptophan (Trp) in calyx persistence fruitlet (CPF) than calyx shedding fruitlet (CSF) ofDanshan Suli’ pear (Pyrus bretschneideri Rhed.). Consisting with this, the activity of indolealdehyde oxidase (IAAIdO), which promotes IAA synthesis, was remarkably increased, and that of peroxidase(POD), which degrades IAA, dropped markedly in CPF but not in CSF. Further, qRT-PCR results revealed that most of 31 PbrARFs (encoding auxin response factors) in Pyrus bretschneideri were highly expressed in CPF, whereas PbrARF4, PbrARF24 and PbrARF26 were significantly downregulated in CPF vis-a-vis CSF. Phylogenetic analysis revealed that 6 PbrARFs clustered in the group III, where PbrARF4 showed the closest affinity with AtARF1 that promotes organ abscission, indicating a putative role of PbrARF4 in mediating the process of calyx shedding in pear. In fact, the ectopic overexpression of PbrARF4 in Solanum lycopersicum resulted in an earlier-formed and deeper abscission layer (AL) in the transgenic plants, whose calyxes were more prone to wilt at the mature red stage (MR) compared with the control plants (wild-type). More importantly, expression levels of the abscission genes SILS and Sl Cel2 in transgenic plants overexpressing PbrARF4 were significantly upregulated in comparation with the WT, whereas those of Sl BI and Sl TAPG2 were considerably inhibited. Further, PbrJOINTLESS and PbrIDA,the two genes related to calyx shedding in pear, were up-regulated more in CSF than CPF. The findings contribute to a better understanding of PbrARFs involved in fruitlet calyx shedding of pear, which could prove beneficial to improving the quality of pear fruit.

植入式神经电极阵列器件与材料的研究进展

人脑与电脑通过连续高通量的信息交互来实现深度融合是神经工程领域的重要发展愿景。脑机融合技术不但可以大幅提升运动残障、精神疾病、感知觉缺失能等多种疾病患者的治疗效果,更可以将电子计算机系统中存储的海量信息以及高速数值计算能力直接传递给人脑,从而赋予个人"超能力"。植入式神经电极阵列是发展宽带脑机融合智能系统所不可或缺的关键界面器件。一方面,植入式电极阵列可以同时保证大范围和高精度地记录神经元动作电位的精确发放时间和波形,为充分抽提神经信息,解读脑神经网络的活动奠定坚实基础。另一方面,借助植入式电极阵列对神经元进行高时空精度地信息写入,不但可以向脑内直接传入新信息,也可能改变神经精神疾病(例如帕金森氏症、癫痫和重度抑郁等)患者的异常神经网络活动,从而缓解症状或治疗疾病。电极阵列的微纳加工工艺、电极的理化特征及其与神经组织的界面效应是目前脑机接口技术前端研究的重要方向,而纳米材料和纳米器件等新技术在神经电子界面优化方面的重要作用也愈发明显。

用于二氧化碳电催化还原的电解器研究进展

可再生能源驱动的二氧化碳电催化还原反应(CO_(2)RR)是实现CO_(2)高效转化和利用的有效途径。电解器的理性设计对于提高CO_(2)RR性能及其工业放大应用具有重要意义。电解器构型及其操作条件在很大程度上决定了电极附近的局部反应环境,从而调变催化性能。本文深度剖析了三种CO_(2)电解器(H型电解池、流动电解池和膜电极电解池)的研究进展和现状,结合文献报道,在电流密度、法拉第效率、能量效率和稳定性等四个关键性能参数上比较和讨论了不同电解器构型的优缺点及其对CO_(2)RR性能的影响。面向实际应用的CO_(2)RR研究应该把工业级电流密度作为提高其它三个指标的前提。尽管目前还存在一些问题和挑战,膜电极电解器被认为是最具工业应用前景的技术方案。本文最后提出了一些可能的研究策略和机遇,展望了该领域的未来发展趋势。

Electrochemical synthesis of catalytic materials for energy catalysis

Electrocatalysis is a process dealing with electrochemical reactions in the interconversion of chemical energy and electrical energy.Precise synthesis of catalytically active nanostructures is one of the key challenges that hinder the practical application of many important energy‐related electrocatalytic reactions.Compared with conventional wet‐chemical,solid‐state and vapor deposition synthesis,electrochemical synthesis is a simple,fast,cost‐effective and precisely controllable method for the preparation of highly efficient catalytic materials.In this review,we summarize recent progress in the electrochemical synthesis of catalytic materials such as single atoms,spherical and shaped nanoparticles,nanosheets,nanowires,core‐shell nanostructures,layered nanomaterials,dendritic nanostructures,hierarchically porous nanostructures as well as composite nanostructures.Fundamental aspects of electrochemical synthesis and several main electrochemical synthesis methods are discussed.Structure‐performance correlations between electrochemically synthesized catalysts and their unique electrocatalytic properties are exemplified using selected examples.We offer the reader with a basic guide to the synthesis of highly efficient catalysts using electrochemical methods,and we propose some research challenges and future opportunities in this field.

Amorphous Sn(HPO_(4))_(2)-derived phosphorus-modified Sn/SnO_(x) core/shell catalyst for efficient CO_(2) electroreduction to formate

Simultaneously achieving high activity,selectivity and stability for electrochemical CO_(2)reduction reaction(CO_(2)RR)remains great challenges.Herein,a phosphorus-modified Sn/Sn Oxcore/shell(P-Sn/SnO_x)catalyst,derived from in situ electrochemical reduction of an amorphous Sn(HPO_(4))_(2) pre-catalyst,exhibits high CO_(2)RR performance.The total Faradaic efficiency(FE)of C_(1) products is close to 100%in a broad potential range from-0.49 to-1.02 V vs.reversible hydrogen electrode,and a total current density of 315.0 m A cm^(-2)is achieved.Moreover,the P-Sn/SnO_(x) catalyst maintains a formate FE of~90%for 120 h.Density functional theory calculations suggest that the phosphorus-modified Sn/SnO_(x) core/shell structure effectively facilitates formate production by enhancing CO_(2)adsorption and improving free energy profile of formate formation.

纳米氧化铜片用于高效电化学还原一氧化氮

一氧化氮电还原反应将工业废气转化为有价值的氨,表现出极具潜力的应用前景.在本工作中,我们合成了具有高比表面积和丰富缺陷的氧化铜纳米片催化剂,在流动池中氨法拉第效率达到92.1%,在-0.2 V vs.RHE时,一氧化氮电还原电流密度和氨的生产速率分别达到1.1 A cm^(-2)和7356μmol cm^(-2)h^(-1).在电流密度超过400 m A cm-2时,氨法拉第效率在50小时保持在80%以上.准原位X射线光电子能谱和原位X射线吸收光谱结果表明氧化铜纳米片在一氧化氮电还原过程中被电化学还原成单质铜.与铜纳米颗粒相比,氧化铜纳米片展现出较高的电化学表面积和一氧化氮电还原的内在活性.

芪附理中灌肠方对溃疡性结肠炎模型大鼠肠黏膜机械屏障的影响及机制研究

目的观察芪附理中灌肠方对脾肾阳虚型溃疡性结肠炎模型大鼠肠黏膜机械屏障的影响, 探讨其作用机制。方法将70只雄性SD大鼠按随机数字表法分为空白组、模型组、美沙拉嗪组及芪附理中灌肠方高、中、低剂量组, 空白组10只, 其余各组12只。除空白组外, 其余各组采用苦寒泻下法(大黄煎剂)合并三硝基苯磺酸(TNBS)/55%乙醇复合法诱导法制备UC大鼠模型。造模成功后, 空白组和模型组灌肠生理盐水1 ml, 芪附理中灌肠方高、中、低剂量组灌肠芪附理中汤药液3.00、1.50、0.75 g/kg, 美沙拉嗪组灌肠美沙拉嗪溶液0.03 g/kg, 1次/d, 连续干预14 d。14 d后进行疾病活动指数(DAI)评分, 采用HE染色观察结肠病理组织, 免疫组化染色和Western blot法检测结肠组织闭合蛋白(Occludin)及连接黏附分子A(JAM-A)蛋白表达。结果 HE染色结果显示, 模型组黏膜结构破坏, 炎症细胞浸润, 可见水肿和溃疡灶;美沙拉嗪组及芪附理中灌肠方各剂量组黏膜结构较完整, 可见新生上皮炎症浸润、水肿、溃疡均有好转。与模型组比较, 芪附理中灌肠方各剂量组DAI评分降低(P<0.01), 芪附理中灌肠方高、中剂量组结肠组织Occludin、JAM-A蛋白表达升高(P<0.05)。结论芪附理中灌肠方可缓解UC大鼠症状及病理形态, 其修复肠黏膜屏障的作用机制可能与上调Occludin、JAM-A蛋白表达有关。

Design and development of strip electrode power supply for HEPS wiggler

Purpose The high-energy photon source(HEPS)is the first fourth-generation synchrotron photon source in China(Jiang et al.in Sci Sin Phys Mech Astron 44:1075-1094,2014).The strip electrode and its power supply provide necessary hardware support for correcting the magnetic field of the wiggler as reported by Zhao and Yin(Particle accelerator technology,Higher Education Press,Beijing,2006).The design of the conventional power supply for accelerators,with a large output current and high output voltage,making it easy to achieve high stability of the output current.The strip electrode power supply poses difficulties in achieving high stability due to its small output current and voltage.Because of size limitations,as well as the requirements of the power architecture,there are currently no commercial products for this type of power supply.Methods Designed and developed 32 strip electrode power supplies.Considering the large number of power supplies and limited space,a rack structure design was adopted,placing all power supplies in one rack.The main circuit of the power supply adopts a full bridge transformation structure(Chao et al.in Radiat Detect Technol Methods 6:470-478,2022),and the control scheme adopts full digital control based on FPGA(Long and Cheng in At Energy Sci Technol 43:780-784,2009).The power supply has two control modes:local operation and remote operation as reported by Lu(Particle accelerator technology,Hunan University,Changsha,2010).Results The test shows that all power supplies meet the indicator requirements,with a stability of less than 100 ppm.Conclusions The strip electrode power supply can effectively correct the multipole integral field error and improve the integral field performance of the wiggler.

安徽某铁矿不同矿山废水库中微生物群落结构特征

【目的】研究安徽某铁矿不同矿山废水库中微生物群落结构特征及其影响因素。【方法】对比分析了该铁矿3个大型废水库的地球化学特征,并用高通量测序技术研究了水体中微生物群落组成,进而用统计学方法解析了环境因子对微生物群落结构的影响。【结果】3个废水库中有2个为酸性,1个为中性,理化性质有明显的差异。近年形成的塌方采场废水库(TF) pH仅为2.55±0.01,Fe浓度高达154.95±0.78mg/L,SO42–浓度为3374.86±3.81mg/L;形成于20世纪70年代的排土场废水库(PT)酸性略弱(pH 2.9±0.02),Fe浓度(34.57±4.00 mg/L)与TF相比明显降低,SO42–浓度则高达10398.98±626.70 mg/L;东沙采场废水库(DS)则为中性(pH7.55),但SO42–仍高达4162.99mg/L,主要的金属离子为Mg(594.90 mg/L)、Ca (650.10 mg/L)。3个废水库的原核生物多样性随pH的升高而升高。两个酸性废水库的原核生物组成较为接近,但TF的化能自养菌含量较高(69.54%±2.89%),PT的化能异养菌含量较高(64.45%±13.81%)。自养铁氧化菌Ferrovum在TF中的比例高达(64.17±1.84)%,在PT中则下降为(35.39±13.74)%。但PT中含有丰富的化能异养嗜酸菌如Acidicapsa(15.75%±3.99%)、Acidiphilium(10.65%±2.05%)、Acidisphaera (6.34%±1.02%)等。DS中虽然也含有较高的金属离子和SO42–,但其中的原核生物组成与TF和PT截然不同,主要为Limnohabitans (18.47%)、Rhodobacter (8.42%)等。3个废水库的真核生物群落主要由藻类组成,酸水库TF和PT中主要为棕鞭藻属(Ochromonas)和胶球藻属(Coccomyxa),棕鞭藻属在TF中(53.65%±2.02%)占优势,胶球藻属在PT中(68.84±10.4%)占优势,中性废水库DS中则主要是小环藻属(Cyclotella)(49.85%)。经统计学分析,pH是影响矿山废水微生物多样性和群落组成的主要环境因素。

Reliability and reliability sensitivity analysis of structure by combining adaptive linked importance sampling and Kriging reliability method

The application of reliability analysis and reliability sensitivity analysis methods to complicated structures faces two main challenges:small failure probability(typical less than 10-5)and time-demanding mechanical models.This paper proposes an improved active learning surrogate model method,which combines the advantages of the classical Active Kriging–Monte Carlo Simulation(AK-MCS)procedure and the Adaptive Linked Importance Sampling(ALIS)procedure.The proposed procedure can,on the one hand,adaptively produce a series of intermediate sampling density approaching the quasi-optimal Importance Sampling(IS)density,on the other hand,adaptively generate a set of intermediate surrogate models approaching the true failure surface of the rare failure event.Then,the small failure probability and the corresponding reliability sensitivity indices are efficiently estimated by their IS estimators based on the quasi-optimal IS density and the surrogate models.Compared with the classical AK-MCS and Active Kriging–Importance Sampling(AK-IS)procedure,the proposed method neither need to build very large sample pool even when the failure probability is extremely small,nor need to estimate the Most Probable Points(MPPs),thus it is computationally more efficient and more applicable especially for problems with multiple MPPs.The effectiveness and engineering applicability of the proposed method are demonstrated by one numerical test example and two engineering applications.

MouseVenue3D:A Markerless Three-Dimension Behavioral Tracking System for Matching Two-Photon Brain Imaging in Free-Moving Mice

Understanding the connection between brain and behavior in animals requires precise monitoring of their behaviors in three-dimensional(3-D)space.However,there is no available three-dimensional behavior capture system that focuses on rodents.Here,we present MouseVenue3D,an automated and low-cost system for the efficient capture of 3-D skeleton trajectories in markerless rodents.We improved the most time-consuming step in 3-D behavior capturing by developing an automatic calibration module.Then,we validated this process in behavior recognition tasks,and showed that 3-D behavioral data achieved higher accuracy than 2-D data.Subsequently,MouseVenue3D was combined with fast high-resolution miniature two-photon microscopy for synchronous neural recording and behavioral tracking in the freely-moving mouse.Finally,we successfully decoded spontaneous neuronal activity from the 3-D behavior of mice.Our findings reveal that subtle,spontaneous behavior modules are strongly correlated with spontaneous neuronal activity patterns.

ROS‑Scavenging Electroactive Polyphosphazene‑Based Core–Shell Nanofibers for Bone Regeneration

Bone defects are always accompanied by inflammation due to excessive reactive oxygen species(ROS)in injured regions,which greatly impedes the regeneration of bone tissues.Although many conductive polymers have been developed to scavenge ROS,they are typically non-degradable under physiological conditions,making them unsuitable for in vivo applications.Biodegradable polyorganophosphazenes(POPPs)may serve as potent ROS-scavenging biomaterials owing to their versatile chemical structures and ease of functionalization.Herein,a PATGP-type electroactive polyphosphazene with side groups of aniline tetramer and glycine ethyl ester was compared to conventional poly(lactic-co-glycolic acid)(PLGA)in regenerating bone tissues.To conduct in vitro and in vivo evaluations,three kinds of electrospun nanofibrous meshes were prepared:PLGA,PLGA/PATGP blend,and PLGA/PATGP core–shell nanofibers.Among them,PLGA/PATGP core–shell nanofibers outperform the blend and PLGA nanofibers in terms of scavenging ROS,promoting osteogenic differentiation,and accelerating neo-bone formation.The continuous PATGP shell on the PLGA/PATGP core–shell nanofiber surface could apparently provide more significant modulation effects on cellular behaviors than the PLGA/PATGP blend nanofibers with PATGP dispersed in the PLGA matrix.Therefore,the core–shell structured PLGA/PATGP nanofibers were envisioned as a promising candidate scaffold for bone tissue engineering.Additionally,the core–shell design paved the way for biomedical applications of functional POPPs in combination with other polymeric biomaterials,without phase separation or difficulty of increasing the molecular weights of POPPs.

CO2 electrolysis at industrial current densities using anion exchange membrane based electrolyzers

Significant progress on electrocatalytic CO2 reduction reaction (CO2RR) has been achieved in recent years.However,the research and development of electrolyzer device for CO2RR is scarce.Here we use anion exchange membrane to develop zerogap electrolyzers for CO2RR.The electrochemical properties of the electrolyzers with Pd/C and Cu cathodes are investigated.The Pd/C cathode shows a current density of 200 mA cm^-2with CO Faradaic efficiency of 98%and energy efficiency of 48.8%,while the Cu cathode shows a current density of 350 mA cm^-2with total CO2RR Faradaic efficiency of 81.9%and energy efficiency of 30.5%.This work provides a promising demonstration of CO2 electrolyzer using anion exchange membrane for CO2 electrolysis at industrial current densities.

Crack identification method of highway tunnel based on image processing

In this paper,the images of tunnel surface are obtained by tunnel lining rapid inspection system,and tunnel crack forest dataset(TCFD)is established.The disaster characteristics of tunnel cracks are analyzed and summarized.Solutions of tunnel crack segmentation(TCS)method are developed for the detection and recognition of cracks on tunnel lining.According to the image features of the tunnel lining and the optical principal of detection equipment,effective image pre-processing steps are carried out before crack extraction.The tunnel image of TCFD is divided into appropriate number of blocks to magnify the local features of tunnel cracks.Local threshold segmentation method is used to traverse the blocks successively,and the first target block with crack is obtained.The seed in the target block were obtained by adaptive localization method and mapped to the whole image.Region growing is performed through crack seed until complete tunnel crack is extracted.The results show that the precision,recall rate and F-measure of tunnel cracks under the TCS method can reach 92.58%,93.07%and 92.82%without strong interference.According to the binary images processed by TCS method,the projection images of different types of tunnel cracks and their respective laws are obtained.Furthermore,the TCS method is implemented and deployed as a GUI software application.

Reduced Firing of Nucleus Accumbens Parvalbumin Interneurons Impairs Risk Avoidance in DISC1 Transgenic Mice

A strong animal survival instinct is to approach objects and situations that are of benefit and to avoid risk.In humans,a large proportion of mental disorders are accompanied by impairments in risk avoidance.One of the most important genes involved in mental disorders is disrupted-in-schizophrenia-1(DISC1),and animal models in which this gene has some level of dysfunction show emotion-related impairments.However,it is not known whether DISC1 mouse models have an impairment in avoiding potential risks.In the present study,we used DISC1-N terminal truncation(DISC1-N^(TM))mice to investigate risk avoidance and found that these mice were impaired in risk avoidance on the elevated plus maze(EPM)and showed reduced social preference in a three-chamber social interaction test.Following EPM tests,c-Fos expression levels indicated that the nucleus accumbens(NAc)was associated with risk-avoidance behavior in DISC1-N^(TM)mice.In addition,in vivo electrophysiological recordings following tamoxifen administration showed that the firing rates of fast-spiking neurons(FS)in the NAc were significantly lower in DISC1-N^(TM)mice than in wild-type(WT)mice.In addition,in vitro patch clamp recording revealed that the frequency of action potentials stimulated by current injection was lower in parvalbumin(PV)neurons in the NAc of DISC1-N^(TM)mice than in WT controls.The impairment of risk avoidance in DISC1-N^(TM)mice was rescued using optogenetic tools that activated NAcPV neurons.Finally,inhibition of the activity of NAcPV neurons in PV-Cre mice mimicked the risk-avoidance impairment found in DISC1-N^(TM)mice during tests on the elevated zero maze.Taken together,our findings confirm an impairment in risk avoidance in DISC1-N^(TM)mice and suggest that reduced excitability of NAc^(PV) neurons is responsible.

Catch bond-inspired hydrogels with repeatable and loading rate-sensitive specific adhesion

Biological receptor-ligand adhesion governed by mammalian cells involves a series of mechanochemical pro-cesses that can realize reversible,loading rate-dependent specific interfacial bonding,and even exhibit a counterintuitive behavior called catch bonds that tend to have much longer lifetimes when larger pulling forces are applied.Inspired by these catch bonds,we designed a hydrogen bonding-meditated hydrogel made from acrylic acid-N-acryloyl glycinamide(AA-NAGA)copolymers and tannic acids(TA),which formed repeatable specific adhesion to polar surfaces in an ultra-fast and robust way,but hardly adhered to nonpolar materials.It demonstrated up to five-fold increase in shear adhesive strength and interfacial adhesive toughness with external loading rates varying from 5 to 500 mm min^(-1).With a mechanochemical coupling model based on Monte Carlo simulations,we quantitatively revealed the nonlinear dependence of rate-sensitive interfacial adhesion on external loading,which was in good agreement with the experimental data.Likewise,the developed hydrogels were biocompatible,possessed antioxidant and antibacterial properties and promoted wound healing.This work not only reports a stimuli-responsive hydrogel adhesive suitable for multiple biomedical applications,but also offers an innovative strategy for bionic designs of smart hydrogels with loading rate-sensitive specific adhesion for various emerging areas including flexible electronics and soft robotics.

海马-内嗅皮层结构中发作传播的光感基因剖析

背景颞叶癫痫(Temporal lobe epilepsy,TLE)是起源于海马和海马旁(Hippocampal and parahippocampal,HP-PHP)结构的自发性发作.剖自HP-PHP结构中发作传播的机制对于开发特异性的治疗靶点,进而更有效的治疗TLE至关重要.许多研究人员使用传统的膜片钳分析海马内嗅皮层(Hippocampalentorhinal cortex,HP-EC)脑切片以识别异常环路的发作传播路径.

An Easily Compatible Eye-tracking System for Freely-moving Small Animals

Measuring eye movement is a fundamental approach in cognitive science as it provides a variety of insightful parameters that reflect brain states such as visual attention and emotions.Combining eye-tracking with multimodal neural recordings or manipulation techniques is beneficial for understanding the neural substrates of cognitive function.Many commercially-available and custom-built systems have been widely applied to awake,head-fixed small animals.However,the existing eyetracking systems used in freely-moving animals are still limited in terms of their compatibility with other devices and of the algorithm used to detect eye movements.Here,we report a novel system that integrates a general-purpose,easily compatible eye-tracking hardware with a robust eye feature-detection algorithm.With ultra-light hardware and a detachable design,the system allows for more implants to be added to the animal's exposed head and has a precise synchronization module to coordinate with other neural implants.Moreover,we systematically compared the performance of existing commonly-used pupil-detection approaches,and demonstrated that the proposed adaptive pupil feature-detection algorithm allows the analysis of more complex and dynamic eye-tracking data in freemoving animals.Synchronized eye-tracking and electroencephalogram recordings,as well as algorithm validation under five noise conditions,suggested that our system is flexibly adaptable and can be combined with a wide range of neural manipulation and recording technologies.