The pulsed high magnetic field facility and scientific research at Wuhan National High Magnetic Field Center

Wuhan National High Magnetic Field Center(WHMFC)at Huazhong University of Science and Technology is one of the top-class research centers in the world,which can offer pulsed fields up to 90.6 T with different field waveforms for scientific research and has passed the final evaluation of the Chinese government in 2014.This paper will give a brief introduction of the facility and the development status of pulsed magnetic fields research at WHMFC.In addition,it will describe the application development of pulsed magnetic fields in both scientific and industrial research.

A Robotic System with Robust Remote Center of Motion Constraint for Endometrial Regeneration Surgery

Surgical robots have been widely used in diferent procedures to improve and facilitate the surgery.However,there is no robot designed for endometrial regeneration surgery,which is a new therapy for restoring fertility in women using stem cells.Endometrial regeneration surgery requires processing of the endometrium and transplantation of stem cells with minimal trauma to the uterus.In this paper,we introduce a surgical robotic system that consists of a dexterous hysteroscope,supporting arm,and additional novel instruments to facilitate the operation and decrease trauma to the uterus.Remote center of motion(RCM)constraint is required to protect the cervix of the uterus.First,the supporting arm and hysteroscope are controlled separately in kinematics to ensure that the RCM constraint and hysteroscope’s shape and posture are predictable.Then,a task-decoupled method is used to improve the robustness of the RCM constraint.Experiments confrm that the proposed method is more robust and achieves higher RCM accuracy.In addition,the master-slave control of a robot with RCM constraint is also verifed.This study proposes the realization of a robot with robust RCM control for endometrial regeneration surgery.

Design of Network Cascade Structure for Image Super-Resolution

Image super resolution is an important field of computer research.The current mainstream image super-resolution technology is to use deep learning to mine the deeper features of the image,and then use it for image restoration.However,most of these models mentioned above only trained the images in a specific scale and do not consider the relationships between different scales of images.In order to utilize the information of images at different scales,we design a cascade network structure and cascaded super-resolution convolutional neural networks.This network contains three cascaded FSRCNNs.Due to each sub FSRCNN can process a specific scale image,our network can simultaneously exploit three scale images,and can also use the information of three different scales of images.Experiments on multiple datasets confirmed that the proposed network can achieve better performance for image SR.

Comparative Analysis of Safety and Effect of Minimally Invasive Esophageal Cancer Radical Resection and Conventional Thoracotomy for Esophageal Cancer

Objective:To compare the clinical effects of minimally invasive esophageal cancer radical resection and traditional esophageal cancer radical resection.Methods:200 cases of esophageal cancer radical resection were performed from July 2014 to July 2017 in our hospital.The cases were divided into experimental group and control group,82 cases in the experimental group and 118 cases in the control group.The experimental group was treated with minimally invasive esophageal cancer radical surgery,and the control group was treated with conventional thoracotomy.Record the comparison between the two groups:(1)surgical conditions,including the time of surgery,intraoperative blood loss,hospitalization time;(2)the number of lymph nodes cleaned;(3)the postoperative control group used conventional thoracotomy,including lung lesions,anastomotic fistula/narrow.Results:The parameters of operation time,intraoperative blood loss,hospitalization time,and number of lymph nodes cleaned in the experimental group were lower than those in the control group,and the difference was statistically significant(p<0.05).In addition to pulmonary infection(p<0.05),there was no significant difference in the incidence of other complications between the experimental group and the control group(p>0.05).Conclusion:Minimally invasive esophageal cancer radical resection and conventional thoracotomy have good clinical effects in the treatment of esophageal cancer.Minimally invasive esophageal cancer radical surgery can effectively reduce intraoperative trauma and postoperative reaction,which is worthy of popularization and application.

Extracellular vesicles from human urine-derived stem cells delay aging through the transfer of PLAU and TIMP1

Aging increases the risks of various diseases and the vulnerability to death.Cellular senescence is a hallmark of aging that contributes greatly to aging and aging-related diseases.This study demonstrates that extracellular vesicles from human urine-derived stem cells(USC-EVs)efficiently inhibit cellular senescence in vitro and in vivo.The intravenous injection of USC-EVs improves cognitive function,increases physical fitness and bone quality,and alleviates aging-related structural changes in different organs of senescence-accelerated mice and natural aging mice.The anti-aging effects of USC-EVs are not obviously affected by the USC donors’ages,genders,or health status.Proteomic analysis reveals that USC-EVs are enriched with plasminogen activator urokinase(PLAU)and tissue inhibitor of metalloproteinases 1(TIMP1).These two proteins contribute importantly to the anti-senescent effects of USC-EVs associated with the inhibition of matrix metalloproteinases,cyclin-dependent kinase inhibitor 2A(P16INK4a),and cyclin-dependent kinase inhibitor 1A(P21cip1).These findings suggest a great potential of autologous USC-EVs as a promising anti-aging agent by transferring PLAU and TIMP1 proteins.

Generating electron spin qubit in metal-organic frameworks via spontaneous hydrolysis

Qubit,as the basic unit of quantum operations,has at least two quantum states for superposition.Diamond itself has no superimposable quantum states,but after injecting N atoms,the resulted nitrogenvacancy centers form excellent-performance qubits.For the same purpose,we can also obtain qubits by modifying the matrix without effective quantum states.HKUST-1({Cu_(3)(BTC)_(2)(H_(2)O)_(3)},BTC=1,3,5-benzene-tricarboxylate)with S=0 ground state is electron paramagnetic resonance(EPR)silent,so it is not a qubit candidate.However,the spontaneously hydrolyzed HKUST-1 produces dilute uncoupled Cu^(Ⅱ)ions with S=1/2.In this paper,we utilized the hydrolysis products of HKUST-1 to obtain qubits and assembled a core-shell structural HKUST-1@ZIF-8 by ZIF-8({Zn(mim)_(2)},mim=2-methylimidazole)coated over HKUST-1 for controlling the hydrolysis.The experimental results clearly show that the qubits come from hydrolyzed Cu^(Ⅱ)ions.Furthermore,the dilute uncoupled Cu^(Ⅱ)ions in this assembly can effectively reduce the decoherence of qubits.The EPR studies show that the T_(2) of this compound is 1067 ns at 10 K.

3D vertically aligned microchannel structure to enhance piezoelectric energy harvesting performance of PZT/PVDF&CNTs piezoelectric composites

Piezoelectric energy harvesters(PEHs)have attracted significant attention with the ability of converting mechanical energy into electrical energy and power the self-powered microelectronic components.Generally,material's superior energy harvesting performance is closely related to its high transduction coefficient(d_(33)×g_(33)),which is dependent on higher piezoelectric coefficient d33 and lower dielectric constantεr of materials.However,the high d33 and lowεr are difficult to be simultaneously achieved in piezoelectric ceramics.Herein,lead zirconate titanate(PZT)based piezoelectric composites with vertically aligned microchannel structure are constructed by phase-inversion method.The polyvinylidene fluoride(PVDF)and carbon nanotubes(CNTs)are mixed as fillers to fabricate PZT/PVDF&CNTs composites.The unique structure and uniformly distributed CNTs network enhance the polarization and thus improve the d33.The PVDF filler effectively reduce theεr.As a consequence,the excellent piezoelectric coefficient(d_(33)=595 pC/N)and relatively low dielectric constant(ε_(r)=1,603)were obtained in PZT/PVDF&CNTs composites,which generated an ultra-high d_(33)×g_(33) of 24,942×10^(−15) m^(2)/N.Therefore,the PZT/PVDF&CNTs piezoelectric composites achieve excellent energy harvesting performance(output voltage:66 V,short current:39.22μA,and power density:1.25μW/mm^(2)).Our strategy effectively boosts the performance of piezoelectric-polymer composites,which has certain guiding significance for design of energy harvesters.

Water quality prediction of copper-molybdenum miningbeneficiation wastewater based on the PSO-SVR model

The mining-beneficiation wastewater treatment is highly complex and nonlinear.Various factors like influent quality,flow rate,pH and chemical dose,tend to restrict the effluent effectiveness of miningbeneficiation wastewater treatment.Chemical oxygen demand(COD)is a crucial indicator to measure the quality of mining-beneficiation wastewater.Predicting COD concentration accurately of miningbeneficiation wastewater after treatment is essential for achieving stable and compliant discharge.This reduces environmental risk and significantly improves the discharge quality of wastewater.This paper presents a novel AI algorithm PSO-SVR,to predict water quality.Hyperparameter optimization of our proposed model PSO-SVR,uses particle swarm optimization to improve support vector regression for COD prediction.The generalization capacity tested on out-of-distribution(OOD)data for our PSOSVR model is strong,with the following performance metrics of root means square error(RMSE)is 1.51,mean absolute error(MAE)is 1.26,and the coefficient of determination(R2)is 0.85.We compare the performance of PSO-SVR model with back propagation neural network(BPNN)and radial basis function neural network(RBFNN)and shows it edges over in terms of the performance metrics of RMSE,MAE and R2,and is the best model for COD prediction of mining-beneficiation wastewater.This is because of the less overfitting tendency of PSO-SVR compared with neural network architectures.Our proposed PSO-SVR model is optimum for the prediction of COD in copper-molybdenum mining-beneficiation wastewater treatment.In addition,PSO-SVR can be used to predict COD on a wide variety of wastewater through the process of transfer learning.

Ultrasensitive solar-blind ultraviolet detection and optoelectronic neuromorphic computing using α-In_(2)Se_(3)phototransistors

Detection of solar-blind ultraviolet(SB-UV)light is important in applications like confidential communication,flame detection,and missile warning system.However,the existing SB-UV photodetectors still show low sensitivities.In this work,we demonstrate the extraordinary SB-UV detection performance of α-In_(2)Se_(3 )phototransistors.Benefiting from the coupled semiconductor and ferroelectricity property,the phototransistor has an ultraweak detectable power of 17.85 fW,an ultrahigh gain of 1.2×10^(6),a responsivity of 2.6×10^(5) A/W,a detectivity of 1.3×10^(16) Jones and an ultralow noise-equivalent-power of 4.2×10^(–20 )W/Hz1/2 for 275 nm light.Its performance exceeds most other UV detectors,even including commercial photomultiplier tubes and avalanche photodiodes.It can be also implemented as an optoelectronic synapse for neuromorphic computing.A 784×300×10 artificial neural network(ANN)based on this optoelectronic synapse is constructed and demonstrated with a high recognition accuracy and good noise-tolerance for the Fashion-MNIST dataset.These extraordinary features endow this phototransistor with the potential for constructing advanced SB-UV detectors and intelligent hardware.

Pulse electrochemical synaptic transistor for supersensitive and ultrafast biosensors

High sensitivity and fast response are the figures of merit for benchmarking commercial sensors.Due to the advantages of intrinsic signal amplification,bionic ability,and mechanical flexibility,electrochemical transistors(ECTs)have recently gained increasing popularity in constructing various sensors.In the current work,we have proposed a pulse-driven synaptic ECT for supersensitive and ultrafast biosensors.By pulsing the presynaptic input(drain bias,VD)and setting the modulation potential(gate bias)near transconductance intersection(VG,i),the synaptic ECT-based pH sensor can achieve a record high sensitivity up to 124 mV pH^(-1)(almost twice the Nernstian limit,59.2 mV pH^(-1))and an ultrafast response time as low as 8.75 ms(7169 times faster than the potentiostatic sensors,62.73 s).The proposed synaptic sensing strategy can effectively eliminate the transconductance fluctuation issue during the calibration process of the pH sensor and significantly reduce power consumption.Besides,the most sensitive working point at VG,i has been elaborately figured out through a series of detailed mathematical derivations,which is of great significance to provide higher sensitivity with quasi-nonfluctuating amplification capability.The proposed electrochemical synaptic transistor paired with an optimized operating gate offers a new paradigm for standardizing and commercializing high-performance biosensors.

Hierarchical pomegranate-structure design enables stress management for volume release of Si anode

Si is a promising anode material for lithium-ion batteries owing to its high theoretical capacity.How-ever,large stress during(de)lithiation induces severe structural pulverization,electrical contact failure,and unstable solid-electrolyte interface,which hampers the practical application of Si anode.Herein,a Si-based anode with a hierarchical pomegranate-structure(HPS-Si)was designed to modulate the stress variation,and a sub-micronized Si-based sphere was assembled by the nano-sized Si nanospheres with sub-nanometer-sized multi-phase modification of the covalently linked SiO_(2-x),SiC,and carbon.The sub-micronized HPS-Si stacked with Si nanospheres can avoid agglomerates during cycling due to the high surface energy of nanomaterials.Meanwhile,the reasonable pore structure from SiO_(2) reduction owing to density difference is enough to accommodate the limited volume expansion.The Si spheres with a size of about 50 nm can prevent self-cracking.SiO_(2-x),and SiC as flexible and rigid layers,have been syner-gistically used to reduce the surface stress of conductive carbon layers to avoid cracking.The covalent bonding immensely strengthens the link of the modification with Si nanospheres,thus resisting stress effects.Consequently,a full cell comprising an HPS-Si anode and a LiCoO_(2) cathode achieved an energy density of 415 Wh kg^(-1) with a capacity retention ratio of 87.9%after 300 cycles based on the active ma-terials.It is anticipated that the hierarchical pomegranate-structure design can provide inspiring insights for further studies of the practical application of silicon anode.

Overcoming Debye length limitations:Three-dimensional wrinkled graphene field-effect transistor for ultra-sensitive adenosine triphosphate detection

Adenosine triphosphate(ATP)is closely related to the pathogenesis of certain diseases,so the detection of trace ATP is of great significance to disease diagnosis and drug development.Graphene field-effect transistors(GFETs)have been proven to be a promising platform for the rapid and accurate detection of small molecules,while the Debye shielding limits the sensitive detection in real samples.Here,a three-dimensional wrinkled graphene field-effect transistor(3D WG-FET)biosensor for ultra-sensitive detection of ATP is demonstrated.The lowest detection limit of 3D WG-FET for analyzing ATP is down to 3.01 aM,which is much lower than the reported results.In addition,the 3D WG-FET biosensor shows a good linear electrical response to ATP concentrations in a broad range of detection from 10 aM to 10 pM.Meanwhile,we achieved ultra-sensitive(LOD:10 aM)and quantitative(range from 10 aM to 100 fM)measurements of ATP in human serum.The 3D WG-FET also exhibits high specificity.This work may provide a novel approach to improve the sensitivity for the detection of ATP in complex biological matrix,showing a broad application value for early clinical diagnosis and food health monitoring.

羊草成熟胚诱导愈伤组织及植株再生系统的优化

羊草(Leymuschinensis)为异源四倍体禾本科牧草,利用成熟胚诱导愈伤组织获得再生植株的效率极低,难以运用遗传转化方法进行品种改良。我们以羊草成熟胚为外植体,使用适宜羊草愈伤组织生长的新型培养基配方,筛选诱导愈伤组织、不定芽分化及生根阶段的最适植物激素浓度、光照和温度条件,从而优化羊草成熟胚的组织培养方案。研究结果表明,羊草成熟胚诱导阶段2,4-D的最适浓度为2.0mg·L^-1,变温暗培养,诱导率可达74.1%;分化阶段6-BA和NAA的最适浓度均为1.0 mg·L^-1,分化率可达57.1%;生根阶段NAA的最适浓度为0.25 mg·L^-1,移栽后成活率为100%。

Alendronate loaded graphene oxide functionalized collagen sponge for the dual effects of osteogenesis and anti-osteoclastogenesis in osteoporotic rats

Graphene Oxide(GO)-related hydrogels have been extensively studied in hard tissue repair,because GO can not only enhance the mechanical properties of polymers but also promote osteogenic differentiation of mesenchymal stem cells.However,simple GO-related hydrogels are not ideal for the repair of osteoporotic bone defects as the overactive osteoclasts in osteoporosis.Alendronate(Aln)is known to inhibit osteoclasts and may bind to GO through covalent connection.Therefore,delivering Aln in GO-related hydrogels may be effective to repair osteoporotic bone defects.Here,we developed a control-released system which is constructed by collagen(Col)-GO sponges loaded with Aln(Col-GO-Aln)for osteoporotic bone defect repair.In vitro,Col-GO-Aln sponges prolonged the release period of Aln,and the sponge containing 0.05%(w/v)GO released Aln faster than sponge with 0.2%GO.Furthermore,tartrate-resistant acid phosphatase(TRAP)and F-actin staining demonstrated that Col-GO-Aln sponges effectively inhibited osteoclastogenesis of monocyte-macrophages.In vivo,micro-CT scan showed that the volume of newborn bone in defect site by 0.05%GO sponge was nearly three times larger than that of other groups.Moreover,the CT and histological examinations of rat femur proved that Col-GO-Aln sponges decreased the number of osteoclasts and suppressed the systemic bone loss in osteoporotic rats.These findings reveal that the application of GO as carriers of anti-osteoporosis drugs is a viable treatment for osteoporosis.The results also underscore the potential of GO-related hydrogels with Aln-releasing capacity for bone regeneration in osteoporosis.

Reconfigurable photovoltaic effect for optoelectronic artificial synapse based on ferroelectric p-n junction

Neuromorphic machine vision has attracted extensive attention on wide fields.However,both current and emerging strategies still suffer from power/time inefficiency,and/or low compatibility,complex device structure.Here we demonstrate a driving-voltage-free optoelectronic synaptic device using non-volatile reconfigurable photovoltaic effect based on MoTe_(2)/α-In_(2)Se_(3) ferroelectric p-n junctions.This function comes from the non-volatile reconfigurable built-in potential in the p-n junction that is related to the ferroelectric polarization inα-In_(2)Se_(3).Reconfigurable rectification behavior and photovoltaic effect are demonstrated firstly.Notably,the figure-of-merits for photovoltaic effect like photoelectrical conversion efficiency non-volatilely increases more than one order.Based on this,retina synapse-like vision functions are mimicked.Optoelectronic short-term and long-term plasticity,as well as basic neuromorphic learning and memory rule are achieved without applying driving voltage.Our work highlights the potential of ferroelectric p-n junctions for enhanced solar cell and low-power optoelectronic synaptic device for neuromorphic machine vision.

Subthermionic field-effect transistors with sub-5 nm gate lengths based on van der Waals ferroelectric heterostructures

Overcoming the sub-5 nm gate length limit and decreasing the power dissipation are two main objects in the electronics research field. Besides advanced engineering techniques, considering new material systems may be helpful. Here, we demonstrate two-dimensional(2D) subthermionic field-effect transistors(FETs) with sub-5 nm gate lengths based on ferroelectric(FE) van der Waals heterostructures(vdWHs).The FE vd WHs are composed of graphene, MoS2, and CuInP2S6 acting as 2D contacts, channels, and ferroelectric dielectric layers, respectively. We first show that the as-fabricated long-channel device exhibits nearly hysteresis-free subthermionic switching over three orders of magnitude of drain current at room temperature. Further, we fabricate short-channel subthermionic FETs using metallic carbon nanotubes as effective gate terminals. A typical device shows subthermionic switching over five-to-six orders of magnitude of drain current with a minimum subthreshold swing of 6.1 mV/dec at room temperature. Our results indicate that 2D materials system is promising for advanced highly-integrated energy-efficient electronic devices.

Van der Waals integration of 2D atomic crystals for advanced multifunctional devices

Semiconductor heterostructures play a key role in the development of solid-state electronic and optoelectronic devices.They are generally realized via traditional epitaxial integration,namely two or more dissimilar materials,with matching crystal lattice,polarity and thermal expansion coefficients,are grown on the surface of each other.

Water molecule-induced hydrogen bonding between cellulose nanofibers toward highly strong and tough materials from wood aerogel

Lightweight,highly strong and bio-based structural materials remain a long-lasting challenge.Here,inspired by nacre,a lightweight and high mechanical performance cellulosic material was fabricated via a facile and effective top-down approach and the resulting material has a high tensile strength of149.21 MPa and toughness of 1.91 MJ/m^(3).More specifically,the natural balsawood(NW) was subjected to a simple chemical treatment,removing most lignin and partial hemicellulose,follow by freeze-drying,forming wood aerogel(WA).The delignification process produced many pores and exposed numerous aligned cellulose nanofibers.Afterwards,the WA absorbed a quantity of moisture and was directly densified to form above high-performance cellulosic material.Such treatment imitates highly ordered"brick-and-mortar" arrangement of nacre,in which water molecules plays the role of mortar and cellulose nanofibrils make the brick part.The lightweight and good mechanical properties make this material promising for new energy car,aerospace,etc.This paper also explains the strengthening mechanism for making biomimetic materials by water molecules-induced hydrogen bonding and will open a new path for designing high-performance bio-based structural materials.

Enhanced thermal and cycling reliabilities in (K,Na)(Nb,Sb)O3-CaZr03-(Bi,Na)Hf03 ceramics

The thermal stability and fatigue resistance of piezoelectric ceramics are of great importance for industrialized application.In this study,the electrical properties of(0.99-x)(K0.48Na0.52)Nb0.975Sb0.025)O3-0.01CaZrO3-x(Bi0.5Na0.5)HfO3 ceramics are investigated.When x=0.03,the ceramics exhibit the optimal electrical properties at room temperature and high Curie temperature(Tc=253℃).In addition,the ceramic has outstanding thermal stability(d33≈301 pm/V at 160℃)and fatigue resistance(variation of Pr and d33~10 %after 10^4 electrical cycles).Subsequently,the defect configuration and crystal structure of the ceramics are studied by X-ray diffraction,temperature-dielectric property curves and impedance analysis.On one hand,the doping(Bio sNao.3)HfO3 makes the dielectric constant peaks flatten.On the other hand,the defect concentration and migration are obviously depressed in the doped ceramics.Both of them can enhance the piezoelectrical properties and improve the temperature and cycling reliabilities.The present study reveals that the good piezoelectric properties can be obtained in 0.96(K0.58Na0.52)(Nb0.975Sb.025)O3-0.01CaZrO3-0.03(Bi0.5Na0.5)HfO3 ceramics.