A phenology-based vegetation index for improving ratoon rice mapping using harmonized Landsat and Sentinel-2 data

Ratoon rice,which refers to a second harvest of rice obtained from the regenerated tillers originating from the stubble of the first harvested crop,plays an important role in both food security and agroecology while requiring minimal agricultural inputs.However,accurately identifying ratoon rice crops is challenging due to the similarity of its spectral features with other rice cropping systems(e.g.,double rice).Moreover,images with a high spatiotemporal resolution are essential since ratoon rice is generally cultivated in fragmented croplands within regions that frequently exhibit cloudy and rainy weather.In this study,taking Qichun County in Hubei Province,China as an example,we developed a new phenology-based ratoon rice vegetation index(PRVI)for the purpose of ratoon rice mapping at a 30 m spatial resolution using a robust time series generated from Harmonized Landsat and Sentinel-2(HLS)images.The PRVI that incorporated the red,near-infrared,and shortwave infrared 1 bands was developed based on the analysis of spectro-phenological separability and feature selection.Based on actual field samples,the performance of the PRVI for ratoon rice mapping was carefully evaluated by comparing it to several vegetation indices,including normalized difference vegetation index(NDVI),enhanced vegetation index(EVI)and land surface water index(LSWI).The results suggested that the PRVI could sufficiently capture the specific characteristics of ratoon rice,leading to a favorable separability between ratoon rice and other land cover types.Furthermore,the PRVI showed the best performance for identifying ratoon rice in the phenological phases characterized by grain filling and harvesting to tillering of the ratoon crop(GHS-TS2),indicating that only several images are required to obtain an accurate ratoon rice map.Finally,the PRVI performed better than NDVI,EVI,LSWI and their combination at the GHS-TS2 stages,with producer's accuracy and user's accuracy of 92.22 and 89.30%,respectively.These results demonstrate that the proposed PRVI based on HLS data can effectively identify ratoon rice in fragmented croplands at crucial phenological stages,which is promising for identifying the earliest timing of ratoon rice planting and can provide a fundamental dataset for crop management activities.

In Situ Deposition of Drug and Gene Nanoparticles on a Patterned Supramolecular Hydrogel to Construct a Directionally Osteochondral Plug

The integrated repair of bone and cartilage boasts advantages for osteochondral restoration such as a long-term repair effect and less deterioration compared to repairing cartilage alone.Constructing multifactorial,spatially oriented scaffolds to stimulate osteochondral regeneration,has immense significance.Herein,targeted drugs,namely kartogenin@polydopamine(KGN@PDA)nanoparticles for cartilage repair and miRNA@calcium phosphate(miRNA@CaP)NPs for bone regeneration,were in situ deposited on a patterned supramolecular-assembled 2-ureido-4[lH]-pyrimidinone(UPy)modified gelation hydrogel film,facilitated by the dynamic and responsive coordination and complexation of metal ions and their ligands.This hydrogel film can be rolled into a cylindrical plug,mimicking the Haversian canal structure of natural bone.The resultant hydrogel demonstrates stable mechanical properties,a self-healing ability,a high capability for reactive oxygen species capture,and controlled release of KGN and miR-26a.In vitro,KGN@PDA and miRNA@CaP promote chondrogenic and osteogenic differentiation of mesenchymal stem cells via the JNK/RUNX1 and GSK-3β/β-catenin pathways,respectively.In vivo,the osteochondral plug exhibits optimal subchondral bone and cartilage regeneration,evidenced by a significant increase in glycosaminoglycan and collagen accumulation in specific zones,along with the successful integration of neocartilage with subchondral bone.This biomaterial delivery approach represents a significant toward improved osteochondral repair.

Optimal parameter space for stabilizing the ferroelectric phase of Hf_(0.5)Zr_(0.5)O_(2) thin films under strain and electric fields

Hafnia-based ferroelectric materials, like Hf_(0.5)Zr_(0.5)O_(2)(HZO), have received tremendous attention owing to their potentials for building ultra-thin ferroelectric devices. The orthorhombic(O)-phase of HZO is ferroelectric but metastable in its bulk form under ambient conditions, which poses a considerable challenge to maintaining the operation performance of HZO-based ferroelectric devices. Here, we theoretically addressed this issue that provides parameter spaces for stabilizing the O-phase of HZO thin-films under various conditions. Three mechanisms were found to be capable of lowering the relative energy of the O-phase, namely, more significant surface-bulk portion of(111) surfaces, compressive c-axis strain,and positive electric fields. Considering these mechanisms, we plotted two ternary phase diagrams for HZO thin-films where the strain was applied along the in-plane uniaxial and biaxial, respectively. These diagrams indicate the O-phase could be stabilized by solely shrinking the film-thickness below 12.26 nm, ascribed to its lower surface energies. All these results shed considerable light on designing more robust and higher-performance ferroelectric devices.

Evolution of the porous structure for phosphoric acid etching carbon as cathodes in Li–O_(2) batteries:Pyrolysis temperature-induced characteristics changes

Although biomass-derived carbon(biochar)has been widely used in the energy field,the relation between the carbonization condition and the physical/chemical property of the product remains elusive.Here,we revealed the carbonization condition's effect on the morphology,surface property,and electrochemical performance of the obtained carbon.An open slit pore structure with shower-puff-like nanoparticles can be obtained by finely tuning the carbonization temperature,and its unique pore structure and surface properties enable the Li–O_(2) battery with cycling longevity(221 cycles with 99.8%Coulombic efficiency at 0.2 mA cm^(−2) and controlled discharge–charge depths of 500 mAh g^(−1))and high capacity(16,334 mAh g^(−1) at 0.02 mA cm^(−2)).This work provides a greater understanding of the mechanism of the biochar carbonization procedure under various pyrolysis conditions,paving the way for future study of energy storage devices.

Memristive feature and mechanism induced by laser-doping in defect-free 2D semiconductor materials

Memristors as non-volatile memory devices have gained numerous attentions owing to their advantages in storage,in-memory computing, synaptic applications, etc. In recent years, two-dimensional(2D) materials with moderate defects have been discovered to exist memristive feature. However, it is very difficult to obtain moderate defect degree in 2D materials, and studied on modulation means and mechanism becomes urgent and essential. In this work, we realized memristive feature with a bipolar switching and a configurable on/off ratio in a two-terminal MoS_(2) device(on/off ratio ~100), for the first time, from absent to present using laser-modulation to few-layer defect-free MoS_(2)(about 10 layers), and its retention time in both high resistance state and low resistance state can reach 2×10^(4) s. The mechanism of the laser-induced memristive feature has been cleared by dynamic Monte Carlo simulations and first-principles calculations. Furthermore, we verified the universality of the laser-modulation by investigating other 2D materials of TMDs. Our work will open a route to modulate and optimize the performance of 2D semiconductor memristive devices.

Influence of Flap Parameters on the Aerodynamic Performance of a Wind-Turbine Airfoil

A numerical method has been used to analyze the flow field related to a NACA 0015 airfoil with and without a flap and assess the influence of the flap height and angle on the surface pressure coefficient,lift coefficient,and drag coefficient.The numerical results demonstrate that the flap can effectively improve the lift coefficient of the airfoil;however,at small attack angles,its influence is significantly reduced.When the angle of attack exceeds the critical stall angle and the flap height is 1.5%of the chord length,the influence of the flap becomes very evident.As the flap height increases,the starting point of the separation vortex gradually moves forward and generates a larger wake vortex.Optimal aerodynamic characteristics are obtained for 1.5%(of the chord length)flap height and a 45°flap angle;in this case,the separation vortex is effectively reduced.

Influence of Trailing-Edge Wear on the Vibrational Behavior of Wind Turbine Blades

To study the impact of the trailing-edge wear on the vibrational behavior of wind-turbine blades,unworn blades and trailing-edge worn blades have been assessed through relevant modal tests.According to these experiments,the natural frequencies of trailing-edge worn blades-1,-2,and-3 increase the most in the second to fourth order,thefifth order increases in the middle,and thefirst order increases the least.The damping ratio data indi-cate that,in general,thefirstfive-order damping ratios of trailing-edge worn blades-1 and trailing-edge worn blades-2 are reduced,and thefirstfive-order damping ratios of trailing-edge worn blades-3 are slightly improved.The mode shape diagram shows that the trailing-edge worn blades-1 and-2 have a large swing in the tip and the blade,whereas the second-and third-order vibration shapes of the trailing edge-worn blade-3 tend to be improved.Overall,all these results reveal that the blade’s mass and the wear area are the main fac-tors affecting the vibration characteristics of wind turbine blades.

Orbital-Ordering Driven Simultaneous Tunability of Magnetism and Electric Polarization in Strained Monolayer VCl_(3)

Two-dimensional(2D)van der Waals magnetic materials have promising and versatile electronic and magnetic properties in the 2D limit,indicating a considerable potential to advance spintronic applications.Theoretical predictions thus far have not ascertained whether monolayer VCl_(3) is a ferromagnetic(FM)or anti-FM monolayer;this also remains to be experimentally verified.We theoretically investigate the influence of potential factors,including C_(3) symmetry breaking,orbital ordering,epitaxial strain,and charge doping,on the magnetic ground state.Utilizing first-principles calculations,we predict a collinear type-Ⅲ FM ground state in monolayer VCl_(3) with a broken C_(3) symmetry,wherein only the former two of three t_(2g)orbitals(a_(1g),e_(g2)^(π)and e_(g1)^(π))are occupied.The atomic layer thickness and bond angles of monolayer VCl_(3) undergo abrupt changes driven by an orbital ordering switch,resulting in concomitant structural and magnetic phase transitions.Introducing doping to the underlying Cl atoms of monolayer VCl_(3) without C_(3) symmetry simultaneously induces in-and out-of-plane polarizations.This can achieve a multiferroic phase transition if combined with the discovered adjustments of magnetic ground state and polarization magnitude under strain.The establishment of an orbital-ordering driven regulatory mechanism can facilitate deeper exploration and comprehension of magnetic properties of strongly correlated systems in monolayer VCl_(3).

Deterministic Learning-Based Neural PID Control for Nonlinear Robotic Systems

Traditional proportional-integral-derivative(PID)controllers have achieved widespread success in industrial applications.However,the nonlinearity and uncertainty of practical systems cannot be ignored,even though most of the existing research on PID controllers is focused on linear systems.Therefore,developing a PID controller with learning ability is of great significance for complex nonlinear systems.This article proposes a deterministic learning-based advanced PID controller for robot manipulator systems with uncertainties.The introduction of neural networks(NNs)overcomes the upper limit of the traditional PID feedback mechanism’s capability.The proposed control scheme not only guarantees system stability and tracking error convergence but also provides a simple way to choose the three parameters of PID by setting the proportional coefficients.Under the partial persistent excitation(PE)condition,the closed-loop system unknown dynamics of robot manipulator systems are accurately approximated by NNs.Based on the acquired knowledge from the stable control process,a learning PID controller is developed to further improve overall control performance,while overcoming the problem of repeated online weight updates.Simulation studies and physical experiments demonstrate the validity and practicality of the proposed strategy discussed in this article.

Gait Recognition Under Different Clothing Conditions Via Deterministic Learning

Dear Editor,This letter deals with the robustness problem of gait recognition method against maximum number of clothing conditions.By selecting four kinds of time-varying silhouette features,gait dynamics underlying different individuals’gait features is effectively modeled by radial basis function(RBF)neural networks through deterministic learning.This kind of dynamics information has little sensitivity to the variance between gait patterns under different clothing conditions.In order to eliminate the effect of clothing differences,the training patterns under different clothing conditions further constitute a uniform training dataset,containing all kinds of gait dynamics under different clothing conditions.A rapid recognition scheme is presented on published gait databases.Extensive experiments demonstrate the efficacy of the proposed method.

Gamma oscillations and their role in orchestrating balance and communication following stroke

Induced brain oscillations in the gamma range have recently garnered attention due to their reported neuroprotective effects in the treatment of Alzheimer’s disease.This method differs from pharmacological approaches by tapping into the neuronal population dynamics that underlie the homeostatic processes in the brain that are crucial for the recovery of function.Recently,induced gamma-range oscillations have been used to improve cerebral blood flow,motor function,and synaptic plasticity in a mouse model of focal stroke,highlighting the broad potential of recruiting intrinsic recovery processes for the treatment of neurological conditions.Addressing open questions,such as the frequency specificity of the benefits,will shed light on the intrinsic processes involved and allow clinicians to optimize recovery after stroke.

基于强化学习的可持续联邦学习激励机制设计

随着数据在互联网、物联网和人工智能等技术中的广泛应用,数据共享成为促进经济和科技发展的关键引擎之一。然而,由于数据隐私和法律等多方面的顾虑,数据共享面临挑战。联邦学习作为一种新兴的机器学习范式,以保护数据隐私的同时促进多方协作而备受关注。本文关注跨孤岛的长期联邦学习合作,旨在解决数据所有者参与合作的成本和风险问题。本文首先建立了动态博弈模型,考虑了联邦客户端之间的互动策略;然后,提出了一种基于强化学习的激励机制,通过中央计划者为不同训练期设定激励,有效地促进客户端的参与。实验证明,该激励方案在提高系统总收益和控制激励成本方面具有显著效果。本文为可持续联邦学习提供了一种有效的激励设计,有望推动数据共享和合作模型在不同领域的应用。

等线我国涂料行业消费税实施效果及优化探析

为了合理引导涂料消费并改善生态环境质量,我国自2015年开始对涂料征收消费税,开征后涂料行业取得了一定的环保产品发展和技术更新。然而,由于我国涂料消费税存在征税环节过前、税率设置单一、相关税目解释不够精细等问题,导致涂料消费税限制高污染型涂料的职能未能得到充分发挥。因此,建议将涂料消费税的征收环节后移至零售环节,根据VOC含量设置累进阶梯式税率,进一步明确税目解释,并考虑将征收方式从“价内税”变为“价外税”形式。

“健脾利湿化瘀方”联合治疗激素敏感性前列腺癌的真实世界研究

目的:观察“健脾利湿化瘀方”联合雄激素受体抑制剂/雄激素合成抑制剂+促性腺激素释放激素激动剂(MAB)治疗激素敏感性前列腺癌(hormone-sensitive prostate cancer,HSPC)的临床疗效。方法:选取2019年11月至2021年6月于天津中医药大学第一附属医院、天津医科大学总医院就诊的HSPC患者100例,随机分为治疗组和对照组各50例,对照组接受MAB治疗,治疗组在对照组基础上给予“健脾利湿化瘀方”。主要观察指标为中位无进展生存期(median progression-free survival,mPFS)、前列腺特异性抗原(prostate specific antigen,PSA);次要观察指标为血清睾酮、中医临床症状评分、肿瘤生存质量调查表(EORTC QLQ-C30)、KPS功能状态评分。结果:治疗组较对照组可延长mPFS 4个月(16个月vs.12个月)、明显降低PSA水平、改善中医临床症状、改善QLQ-C30、提高KPS评分(均P<0.05)。亚组预后因素分析显示,治疗前KPS评分90分组、PSA最低值≤1 ng/mL、PSA下降≥90%的患者在治疗组中获益更显著。结论:“健脾利湿化瘀方”联合MAB治疗延长患者的m PFS,更好地降低PSA水平,实现PSA的深度应答,降低血清睾酮至去势水平,延长激素敏感时间,改善中医临床症状,提高患者的生存质量。

CaREM1.4 interacts with CaRIN4 to regulate Ralstonia solanacearum tolerance by triggering cell death in pepper

Remorins,plant-specific proteins,have a significant role in conferring on plants the ability to adapt to adverse environments.However,the precise function of remorins in resistance to biological stress remains largely unknown.Eighteen CaREM genes were identified in pepper genome sequences based on the C-terminal conserved domain that is specific to remorin proteins in this research.Phylogenetic relations,chromosomal localization,motif,gene structures,and promoter regions of these remorins were analyzed and a remorin gene,CaREM1.4,was cloned for further study.The transcription of CaREM1.4 in pepper was induced by infection with Ralstonia solanacearum.Knocking down CaREM1.4 in pepper using virus-induced gene silencing(VIGS)technologies reduced the resistance of pepper plants to R.solanacearum and downregulated the expression of immunity-associated genes.Conversely,transient overexpression of CaREM1.4 in pepper and Nicotiana benthamiana plants triggered hypersensitive response-mediated cell death and upregulated expression of defense-related genes.In addition,CaRIN4-12,which interacted with CaREM1.4 at the plasma membrane and cell nucleus,was knocked down with VIGS,decreasing the susceptibility of Capsicum annuum to R.solanacearum.Furthermore,CaREM1.4 reduced ROS production by interacting with CaRIN4-12 upon co-injection in pepper.Taken together,our findings suggest that CaREM1.4 may function as a positive regulator of the hypersensitive response,and it interacts with CaRIN4-12,which negatively regulates plant immune responses of pepper to R.solanacearum.Our study provides new evidence for comprehending the molecular regulatory network of plant cell death.

面向无机材料专业的案例式分析化学教学探索与实践

化学分析在建筑材料试验检测中发挥着重要的作用,因此学好分析化学对无机非金属材料工程专业的学生来讲十分必要。本文探索了面向无机非金属材料工程专业的案例式分析化学教学模式,将化学分析在建筑材料试验检测中的应用案例融入课程中,促进专业基础课程和专业的有效衔接;通过采取对比法和联想法等多种教学设计,引导学生积极参与到课程中来,加深学生对理论知识的理解,增强学生对分析化学在本专业中实用性和必要性的认识,做到因材施教和因需施教。

Regulating local coordination environment of Mg-Co single atom catalyst for improved direct methanol fuel cell cathode

Fuel cells operated with a reformate fuel such as methanol are promising power systems for portable electronic devices due to their high safety,high energy density and low pollutant emissions.However,several critical issues including methanol crossover effect,CO-tolerance electrode and efficient oxygen reduction electrocatalyst with low or non-platinum usage have to be addressed before the direct methanol fuel cells(DMFCs)become commercially available for industrial application.Here,we report a highly active and selective Mg-Co dualsite oxygen reduction reaction(ORR)single atom catalyst(SAC)with porous N-doped carbon as the substrate.The catalyst exhibits a commercial Pt/C-comparable half-wave potential of 0.806 V(versus the reversible hydrogen electrode)in acid media with good stability.Furthermore,practical DMFCs test achieves a peak power density of over 200 m W cm^(-2)that far exceeds that of commercial Pt/C counterpart(82 m W cm^(-2)).Particularly,the Mg-Co DMFC system runs over 10 h with negligible current loss under 10 M concentration methanol work condition.Experimental results and theoretical calculations reveal that the N atom coordinated by Mg and Co atom exhibits an unconventional d-band-ditto localized p-band and can promote the dissociation of the key intermediate*OOH into*O and*OH,which accounts for the near unity selective 4e-ORR reaction pathway and enhanced ORR activity.In contrast,the N atom in SAC–Co remains inert in the absorption and desorption of*OOH and*OH.This local coordination environment regulation strategy around active sites may promote rational design of high-performance and durable fuel cell cathode electrocatalysts.

Knowledge,attitude,and practice of monitoring early gastric cancer after endoscopic submucosal dissection

BACKGROUND Early gastric cancer(EGC)is typically treated with endoscopic submucosal dissection(ESD).However,recurrence may occur after ESD,requiring surveillance.AIM To examine the knowledge,attitude,and practice(KAP)of EGC survivors following ESD regarding gastric cancer recurrence.METHODS This cross-sectional study was conducted between June 1,2022 and October 1,2022 in Zhejiang,China.A total of 400 EGC survivors who underwent ESD at the Affiliated Jinhua Hospital,Zhejiang University School of Medicine participated in this study.A self-administered questionnaire was developed to assess KAP monitoring gastric cancer after ESD.RESULTS The average scores for KAP were 3.34,23.76,and 5.75 out of 5,30,and 11,respectively.Pearson correlation analysis revealed positive and significant correlations between knowledge and attitude,knowledge and practice,and attitude and practice(r=0.405,0.511,and 0.458,respectively;all P<0.001).Multivariate logistic regression analysis showed that knowledge,attitude,13-24 mo since the last ESD(vs≤12 mo since the last ESD),and≥25 mo since the last ESD(vs≤12 mo since the last ESD)were independent predictors of proactive practice(odds ratio=1.916,1.253,3.296,and 5.768,respectively,all P<0.0001).CONCLUSION EGC survivors showed inadequate knowledge,positive attitude,and poor practices in monitoring recurrences after ESD.Adequate knowledge,positive attitude,and a longer time since the last ESD were associated with practice.

A Novel RFID Localization Approach to Smart Self-Service Borrowing and Returning System

The misreading problem of a passive ultra-high-frequency(UHF)radio frequency identification(RFID)tag is a frequent problem arising in the field of librarianship.Unfortunately,existing solutions are something inefficient,e.g.,extra resource requirement,inaccuracy,and empiricism.To this end,under comprehensive analysis on the passive UHF RFID application in the librarianship scenario,a novel and judicious approach based on RFID localization is proposed to address such a misreading problem.Extensive simulation results show that the proposed approach can outperform the existing ones and can be an attractive candidate in practice.

Thermoelectric signature of Majorana zero modes in a T-typed double-quantum-dot structure

The thermoelectric effect of the system is theoretically investigated,by coupling Majorana zero mode to the T-typed double-quantum-dot-structure in different ways.It is found that when a single Majorana zero mode is coupled to one of the quantum dots(QDs),the thermoelectric efficiency is suppressed due to the leakage of Majorana zero modes into the QDs.When the Majorana zero mode is coupled to QD2,the suppression of the thermoelectric efficiency is more serious than that of QD1.Furthermore,when two Majorana zero modes are introduced simultaneously,suppression of the thermoelectric effect still takes place.We believe that such results can be candidates for the detection of Majorana bound states and help us understand the role of Majorana zero mode in thermoelectricity.