Oscillation of S5 helix under different temperatures in determination of the open probability of TRPV1 channel

Transient receptor potential vanilloid subtype 1 (TRPV1) is a polymodel sensory receptor and can be activated by moderate temperature (≥ 43 ℃). Though extensive researches on the heat-activation mechanism revealed some key elements that participate in the heat-sensation pathway, the detailed thermal-gating mechanism of TRPV1 is still unclear. We investigate the heat-activation process of TRPV1 channel using the molecular dynamics simulation method at different temperatures. It is found that the favored state of the supposed upper gate of TRPV1 cannot form constriction to ion permeation. Oscillation of S5 helix originated from thermal fluctuation and forming/breaking of two key hydrogen bonds can transmit to S6 helix through the hydrophobic contact between S5 and S6 helix. We propose that this is the pathway from heat sensor of TRPV1 to the opening of the lower gate. The heat-activation mechanism of TRPV1 presented in this work can help further functional study of TRPV1 channel.

Iterated Commutators for Multilinear Singular Integral Operators on Morrey Space with Non-Doubling Measures

Let μ be a non-negative Radon measure on Rd which only satisfies the following growth condition that there exists a positive constant C such that μ(B(x,r)) ≤ Crn?for all x∈ Rd, r > 0 and some fixed n ∈ (0,d]. This paper is interested in the properties of the iterated commutators of multilinear singular integral operators on Morrey spaces?.Precisely speaking, we show that the iterated commutators generated by multilinear singular integrals operators are bounded from to where (Regular Bounded Mean Oscillation space) and 1 qj ≤ pj ∞ with 1/p = 1/p1 + ... + 1/pm and 1/q = 1/q1+ ... + 1/qm.

Biological Tissue-Inspired Ultrasoft,Ultrathin,and Mechanically Enhanced Microfiber Composite Hydrogel for Flexible Bioelectronics

Hydrogels offer tissue-like softness,stretchability,fracture toughness,ionic conductivity,and compatibility with biological tissues,which make them promising candidates for fabricating flexible bioelectronics.A soft hydrogel film offers an ideal interface to directly bridge thin-film electronics with the soft tissues.However,it remains difficult to fabricate a soft hydrogel film with an ultrathin configuration and excellent mechanical strength.Here we report a biological tissue-inspired ultrasoft microfiber composite ultrathin(<5μm)hydrogel film,which is currently the thinnest hydrogel film as far as we know.The embedded microfibers endow the composite hydrogel with prominent mechanical strength(tensile stress~6 MPa)and anti-tearing property.Moreover,our microfiber composite hydrogel offers the capability of tunable mechanical properties in a broad range,allowing for matching the modulus of most biological tissues and organs.The incorporation of glycerol and salt ions imparts the microfiber composite hydrogel with high ionic conductivity and prominent anti-dehydration behavior.Such microfiber composite hydrogels are promising for constructing attaching-type flexible bioelectronics to monitor biosignals.

Experimental investigation on vibration characteristics of the medium-low-speed maglev vehicle-turnout coupled system

The steel turnout is one of the key components in the medium–low-speed maglev line system.However,the vehicle under active control is prone to vehicle–turnout coupled vibration,and thus,it is necessary to identify the vibration characteristics of this coupled system through field tests.To this end,dynamic performance tests were conducted on a vehicle–turnout coupled system in a medium–low-speed maglev test line.Firstly,the dynamic response data of the coupled system under various operating conditions were obtained.Then,the natural vibration characteristics of the turnout were analysed using the free attenuation method and the finite element method,indicating a good agreement between the simulation results and the measured results;the acceleration response characteristics of the coupled system were analysed in detail,and the ride quality of the vehicle was assessed by Sperling index.Finally,the frequency distribution characteristics of the coupled system were discussed.All these test results could provide references for model validation and optimized design of medium–low-speed maglev transport systems.

Quasi-classical Trajectory Study of the Intramolecular Isotope Effect in the Reaction O（3p）＋H2/HD

反应 O (3P )+H2/HD 的动力学的理论研究(v = 0， j = 0 ) OH+H 为最低三位字节在 ab initio 潜力表面上与伪古典的轨道方法(QCT ) 被执行了 H2O (3A'') 的电子状态。QCT 计算的不可分的生气的节在对更早的时间依赖者量力学结果的好同意。解决状态的旋转分布表明产品哦为 O+HD 的旋转分布为高度与 O+H2 反应相比占据内部激动的状态有偏爱。微分生气的节的分布证明散布的方向强烈依赖于量状态的选择。极化依赖者概括了微分剖面图，分布是计算的，显著同位素的效果被揭示。计算结果显示产品极化对集体因素很敏感。

Overexpression of maize GOLDEN2 in rice and maize calli improves regeneration by activating chloroplast development

Golden2(G2), a member of the GARP transcription factor superfamily, regulates several biological processes and phytohormone signaling pathways in plants. In this study, we used a rice codon-optimized maize G2 gene(rZmG2) to improve the regeneration efficiency of rice and maize calli for genetic transformation. We isolated a promoter driving strong and callus-specific expression from rice to drive rZmG2 transcription from a transgene after transformation of two indica and two japonica rice cultivars. The resulting rZmG2 transgenic calli turned green in advance at the differentiation stage, thus significantly raising the regeneration rates of the transgenic indica and japonica rice plants relative to control transformations. Similar effect of this gene on improving maize transformation was also observed. Transcriptome sequencing and RT-qPCR analyses showed that many rice genes related to chloroplast development and phytohormones are upregulated in rZmG2-transgenic calli. These results demonstrate that rZmG2 can promote embryogenic callus differentiation and improve regeneration efficiency by activating chloroplast development and phytohormone pathways. We also established a heat-inducible Cre/loxP-based gene-excision system to remove rZmG2 and the antibiotic selectable gene after obtaining the transgenic plants. This study provides a useful tool for functional genomics work and biotechnology in plants.

Lightweight and Efficient Attention-Based Superresolution Generative Adversarial Networks

To address the problems of lack of high-frequency information and texture details and unstable training in superresolution generative adversarial net-works,this paper optimizes the generator and discriminator based on the SRGAN model.First,the residual dense block is used as the basic structural unit of the gen-erator to improve the network’s feature extraction capability.Second,enhanced lightweight coordinate attention is incorporated to help the network more precisely concentrate on high-frequency location information,thereby allowing the gener-ator to produce more realistic image reconstruction results.Then,we propose a symmetric and efficient pyramidal segmentation attention discriminator network in which the attention mechanism is capable of derivingfiner-grained multiscale spatial information and creating long-term dependencies between multiscale chan-nel attentions,thus enhancing the discriminative ability of the network.Finally,a Charbonnier loss function and a gradient variance loss function with improved robustness are used to better realize the image’s texture structure and enhance the model’s stability.Thefindings from the experiments reveal that the reconstructed image quality enhances the average peak signal-to-noise ratio(PSNR)by 1.59 dB and the structural similarity index(SSIM)by 0.045 when compared to SRGAN on the three test sets.Compared with the state-of-the-art methods,the reconstructed images have a clearer texture structure,richer high-frequency details,and better visual effects.

Copy number variation of NAL23 causes narrow-leaf development in rice

Leaf shape is a key trait for plant architecture relating to photosynthesis and transpiration in plants(Lawson et al.,2020).Erect leaves with proper leaf length and width,particularly the upper three leaves in cereal crops,could significantly improve light absorption efficiency in canopy and ultimately increase crop yield(Jiao et al.,2010).Rice leaves initiate at the peripheral zone of shoot apical meristem,then develop along the proximal-distal,adaxial-abaxial,and mediallateral axes to form a flat symmetric architecture(Du et al.,2018).

A multifunctional flexible sensor based on PI-MXene/SrTiO_(3) hybrid aerogel for tactile perception

The inadequacy of tactile perception systems in humanoid robotic manipulators limits the breadth of available robotic applications.Here,we designed a multifunctional flexible tactile sensor for robotic fingers that provides capabilities similar to those of human skin sensing modalities.This sensor utilizes a novel PI-MXene/SrTiO_(3) hybrid aerogel developed as a sensing unit with the additional abilities of electromagnetic transmission and thermal insulation to adapt to certain complex environments.Moreover,polyimide(PI)provides a high-strength skeleton,MXene realizes a pressure-sensing function,and MXene/SrTiO_(3) achieves both thermoelectric and infrared radiation response behaviors.Furthermore,via the pressure response mechanism and unsteady-state heat transfer,these aerogel-derived flexible sensors realize multimodal sensing and recognition capabilities with minimal cross-coupling.They can differentiate among 13 types of hardness and four types of material from objects with accuracies of 94%and 85%,respectively,using a decision tree algorithm.In addition,based on the infrared radiation-sensing function,a sensory array was assembled,and different shapes of objects were successfully recognized.These findings demonstrate that this PI-MXene/SrTiO_(3) aerogel provides a new concept for expanding the multifunctionality of flexible sensors such that the manipulator can more closely reach the tactile level of the human hand.This advancement reduces the difficulty of integrating humanoid robots and provides a new breadth of application scenarios for their possibility.

A chromosome-level genome assembly of the wild rice Oryza rufipogon facilitates tracing the origins of Asian cultivated rice

Oryza rufipogon Griff.is a wild progenitor of the Asian cultivated rice Oryza sativa.To better understand the genomic diversity of the wild rice,high-quality reference genomes of O.rufipogon populations are needed,which also facilitate utilization of the wild genetic resources in rice breeding.In this study,we generated a chromosome-level genome assembly of O.rufipogon using a combination of short-read sequencing,single-molecule sequencing,BioNano and Hi-C platforms.The genome sequence(399.8 Mb)was assembled into 46 scaffolds on the 12 chromosomes,with contig N50 and scaffold N50 of 13.2 Mb and 20.3 Mb,respectively.The genome contains 36,520 protein-coding genes,and 49.37% of the genome consists of repetitive elements.The genome has strong synteny with those of the O.sativa subspecies indica and japonica,but containing some large structural variations.Evolutionary analysis unveiled the polyphyletic origins of O.sativa,in which the japonica and indica genome formations involved different divergent O.rufipogon(including O.nivara)lineages,accompanied by introgression of genomic regions between japonica and indica.This high-quality reference genome provides insight on the genome evolution of the wild rice and the origins of the O.sativa subspecies,and valuable information for basic research and rice breeding.

Wafer-level and highly controllable fabricated silicon nanowire transistor arrays on （111） silicon-on-insulator （SOl） wafers for highly sensitive detection in liquid and gaseous environments

This paper presents a wafer-level and highly controllable fabrication technology for silicon nanowire field-effect transistor （SiNW-FET arrays） on （111） silicon- on-insulator （SOI） wafers. Herein, 3,000 SiNW FET array devices were designed and fabricated on 4-inch wafers with a rate of fine variety of more than 90% and a dimension deviation of the SiNWs of less than ＋ 20 nm in each array. As such, wafer-level and highly controllable fabricated SiNW FET arrays were realized. These arrays showed excellent electrical properties and highly sensitive determination of pH values and nitrogen dioxide. The high-performance of the SiNW FET array devices in liquid and gaseous environments can enable the detection under a wide range of conditions. This fabrication technology can lay the foundation for the large-scale application of SiNWs.

Progress in Silicon Nanowire-Based Field-Effect Transistor Biosensors for Label-Free Detection of DNA

Silicon nanowire （SiNW）, as one-dimensional semiconducting nanomaterial, has been incorporated into the filed-effect transistor （FET） devices to increase the efficacy and signal-to-noise in DNA sensing applications. Due to the advantages of high sensitivity, excellent selectivity, label-free detection, direct electrical readout, and minia- turization, SiNW FET-based DNA sensors have been regarded as an important tool in applications of molecular di- agnostics, DNA sequencing, gene expressions, and drug discovery. Here, we review the recent progress in SiNW- FET sensors for label-free electrical DNA detection. We first introduce the working principle of SiNW-FET DNA sensors, SiNW fabrication technologies, bio-functionalization on nanowire surface, and enhancement of device sen- sitivity. Then we sum up the applications of SiNW sensors in detection of DNA hybridization, infectious viruses, microRNA, genetic change （DNA mutation, DNA methylation, and DNA repair）, and protein-DNA interactions. We address several crucial points of sensing performance including sensitivity, selectivity, and limit of detection. Finally, the perspectives, challenges, and some solutions of the field are also discussed.

Multifunctional biomimetic tactile system via a stick-slip sensing strategy for human–machine interactions

A tactile sensor system enables natural interaction between humans and machines;this interaction is crucial for dexterous robotic hands,interactive entertainment,and other smart scenarios.However,the lack of sliding friction detection significantly limits the accuracy and scope of interactions due to the absence of sophisticated information,such as slippage,material and roughness of held objects.Here,inspired by the stick-slip phenomena in the sliding process,we have developed a multifunctional biomimetic tactile system based on the stick-slip sensing strategy,which is a universal method to detect slippage and estimate the surface properties of objects by sliding.This system consists of a flexible fingertip-inspired tactile sensor,a read-out circuit and a machinelearning module.Based on the stick-slip sensing strategy,our system was endowed with high recognition rates for slippage detection(100.0%),material classification(93.3%)and roughness discrimination(92.8%).Moreover,robotic hand manipulation,interactive games and object classification are demonstrated with this multifunctional system for comprehensive and promising human-machine interactions.

Simultaneously controlling heat conduction and infrared absorption with a textured dielectric film to enhance the performance of thermopiles

The heat conduction and infrared absorption properties of the dielectric film have a great influence on the thermopile performance.Thinning the dielectric film,reducing its contact area with the silicon substrate,or adding high-absorptivity nano materials has been proven to be effective in improving thermopiles.However,these methods may result in a decrease in the structural mechanical strength and in creases in the fabrication complexity and cost.In this work,a new performa nce-enha ncement strategy for thermopiles by simultaneously con trolling the heat conduction and infrared absorption with a TExtured Dielectric(TEDI)film is developed and presented.The TEDI film is formed in situ by a simple hard-molding process that is compatible with the fabrication of traditional thermopiles.Compared to the control FLat Dielectric(FLDI)film,the intrinsic thermal conductance of the TEDI film can be reduced by〜18-30%,while the in fra red absorptio n can be increased by-7-13%.Corresp on dingly,the responsivity and detectivity of the fabricated TEDI film-based thermopile can be significantly enhanced by〜38-64%.An optimized TEDI film-based thermopile has achieved a responsivity of 156.89 V-W_1 and a detectivity of 2.16×10^(8)cm-Hz^(1/2)·W^(-1),while the response time constant can remain<12 ms.These results exhibit the great potential of using this strategy to develop high-performance thermopiles and enhance other sensors with heat transfer and/or infrared absorption mechanisms.

Wafer-level site-controlled growth of silicon nanowires by Cu pattern dewetting

为控制尺寸、控制地点的非结晶的硅 nanowires 的晶片级的合成的一条途径(-SiNWs) 在这份报纸被介绍。Microscale Cu 模式数组精确在影印石版术并且湿蚀刻的帮助下在 SiO 2 电影上被定义。由于 dewetting， Cu 原子在退火的过程期间缩小到模式的中心，并且与 SiO 2 电影反应为 Si 原子打开一条散开隧道到底层。-SiNWs 最后在 Cu 模式，和罐头的中心成长被改变象 Cu 模式体积， SiO 2 厚度，和退火的时间那样的关键因素调节。这提供一个简单方法综合并且精确地在一个大区域上放一个 SiNW 数组。

A controllable fabrication improved silicon nanowire array sensor on(111)SOI for accurate bio-analysis application

Silicon nanowire field-effect transistor(SiNW-FET)sensors possess the ability of rapid response,real-time,and label-free detection with high sensitivity and selectivity in the analysis of charged molecules.Their nano-scale size makes them well suited for ultralow detection of charged molecules,but also brings the uniformity fabrication challenging,thus limiting their large-scale application.By a horizontal control approach,highly controllable silicon nanowires arrays at the top of the silicon-on-insulator(SOI)wafer(T-SiNW)were developed in our previous work.To further improve the device uniformity,here a novel SiNW fabricated approach was carefully designed by the combination of horizontal and vertical control.The new silicon nanowires appeared at the bottom of the top silicon layer(B-SiNW).The B-SiNW has a relatively low requirement on the fabrication process and better device uniformity compared to T-SiNW.These improvements resulted in the B-SiNW device with a lower current fluctuation(4.1 nA with 5.1%variations)in the flowing liquid,compared to the T-SiNW device(4.4 nA with 11%variations).Further,in quantitative detection of 40 ng/mL MMP-9,the B-SiNW sensors provided larger signals and lower fluctuation(normalized average response value:0.57 with 4.2%variations),compared to the T-SiNW sensors(0.41 with 12.1%variations),thus indicating a more accurate bio-analysis application of the B-SiNW sensor.This work advances the nanowire sensor technology a step closer toward large-scale application to create stable sensing platforms in disease diagnosis and monitoring.

Subcellular localization of PS1 based on PS1/GFP fusing protein

Mutations in presenilin 1(PS1)gene are closely associated with the early onset of familial Alzheimer’s disease(EOFAD).The fusion genes,GFP-PS1(recombinant plasmid pEGFP-C1-PS1)and PS1-GFP(recombinant plasmid pEGFP-N2-PS1)were constructed to study the subcellular localization of PS1 holoprotein.Recombinant plasmids were transiently transfected into two cell lines,HEK293 and CHO,respectively,using the green fluorescence from GFP(green fluorescence protein)as the PS1 localization signal.Then,we observed green fluorescence with a SPOT II(Olympus,BH2)and CONFOCAL microscope(Olympus,FV300)under 488 nm.The results show that PS1 located on the nuclear envelope.A few can be found on the cellular membrane and in the cytosol in a non-homogeneous distribution.

Knowledge-driven material design platform based on the whole-process simulation and modeling

In order to realize the agility,collaboration and visualization of alloy material devel-opment process,a product development platform based on simulation and modeling technologies is established in this study.In this platform,the whole-process simulation module builds multi-level simulation models based on metallurgical mechanisms from the production line level,the thermo-mechanical coupling field level and the microstructure evolution level.The design knowledge management module represents the multi-source heterogeneous material design knowledge through ontology model,including customers’requirement knowledge,material component knowledge,process design knowledge and quality inspection knowledge,and utilizes the case-based reasoning approach to reuse the knowledge.The data-driven modeling module applies machine learning algorithms to mine the relationships between product mechanical properties,material components,and process parameters from historical samples,and utilizes multi-objective optimiza-tion algorithms to find the optimal combination of process parameters.Application of the developed platform in actual steel mills shows that the proposed method helps to improve the efficiency of product design process.

A machine learning-assisted multifunctional tactile sensor for smart prosthetics

The absence of tactile perception limits the dexterity of a prosthetic hand and its acceptance by amputees.Recreating the sensing properties of the skin using a flexible tactile sensor could have profound implications for prosthetics,whereas existing tactile sensors often have limited functionality with cross-interference.In this study,we propose a machine-learning-assisted multifunctional tactile sensor for smart prosthetics,providing a human-like tactile sensing approach for amputations.This flexible sensor is based on a poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)(PEDOT:PSS)-melamine sponge,which enables the detection of force and temperature with low cross-coupling owing to two separate sensing mechanisms:the open-circuit voltage of the sensor as a force-insensitive intrinsic variable to measure the absolute temperature and the resistance as a temperature-insensitive extrinsic variable to measure force.Furthermore,by analyzing the unsteady heat conduction and characterizing it using real-time thermal imaging,we demonstrated that the process of open-circuit voltage variation resulting from the unsteady heat conduction is closely correlated with the heatconducting capabilities of materials,which can be utilized to discriminate between substances.Assisted by the decision tree algorithm,the device is endowed with thermal conductivity sensing ability,which allows it to identify 10 types of substances with an accuracy of 94.7%.Furthermore,an individual wearing an advanced myoelectric prosthesis equipped with the above sensor can sense pressure,temperature,and recognize different materials.We demonstrated that our multifunctional tactile sensor provides a new strategy to help amputees feel force,temperature and identify the material of objects without the aid of vision.

MEMS-based thermoelectric infrared sensors： A review

In the past decade, micro-electromechanical systems （MEMS）-based thermoelectric infrared （IR） sensors have received considerable attention because of the advances in micromachining technology. This paper presents a review of MEMS-based thermoelectric IR sensors. The first part describes the physics of the device and discusses the figures of merit. The second part discusses the sensing materials, thermal isolation micro- structures, absorber designs, and packaging methods for these sensors and provides examples. Moreover, the status of sensor implementation technology is examined from a historical perspective by presenting findings from the early years to the most recent findings.