Diversity of Rogue Wave Solutions to the (1+1)-Dimensional Boussinesq Equation

A periodically homoclinic solution and some rogue wave solutions of (1+1)-dimensional Boussinesq equation are obtained via the limit behavior of parameters and different polynomial functions. Besides, the mathematics reasons for different spatiotemporal structures of rogue waves are analyzed using the extreme value theory of the two-variables function. The diversity of spatiotemporal structures not only depends on the disturbance parameter u0 but also has a relationship with the other parameters c0, α, β.

阿尔茨海默病居家筛查专家共识

老年人痴呆或认知障碍多由一种以上年龄相关的常见脑部疾病所致。阿尔茨海默病(Alzheimer's disease,AD)是其中最常见的神经变性疾病,且是全球前10位死因中唯一无法治愈或缺乏长期对症疗效的疾病,给个人、家庭和全球经济都带来了巨大的负担。早期及时发现和干预是对抗AD的最佳策略。在过去的30年中,许多研究都提出了降低痴呆风险的方法,2020年《柳叶刀》杂志的痴呆预防报告已阐明通过应对风险因素可以预防或延缓超过40%的痴呆。然而,目前全球医疗体系尚未具备早期或及时发现AD的足够能力。最近的一项研究发现,只有不到10%的轻度认知障碍(mild cognitive impairment,MCI)是在初级医疗机构中诊断出来的。近来,抗淀粉样蛋白β(Amyloid beta,Aβ)抗体药物lecanemab和donanemab被批准上市用于早期AD治疗,以及30年的随访研究证明改善风险因素显著减少AD痴呆的发病率并延长了寿命,使得人们对AD早期识别的关注迅速增加。阿尔茨海默病防治协会(China Association for Alzheimer's Disease,CAAD)认识到居家早期和及时发现AD的重要性,并成立了一个由协会成员、临床医生和研究人员组成的全球AD多领域专家团队,就以下目标达成共识:①为个人、家庭、社区、协会和组织提供专家指导意见;②介绍用于认知障碍和痴呆居家筛查的数字工具和可用资源,并为AD高危人群或疑似患者制定下一步应对策略;③讨论现有可用或将来可能的居家筛查适宜AD生物标志物;④为未来的改进和全球应用建立可行性框架。专家组对于当前可用的证据、工具和资源进行综述,并进一步考量其在AD居家筛查中的价值。

Identification, pathogenicity, and fungicide sensitivity of Eutiarosporella dactylidis associated with leaf blight on maize in China

Maize(Zea mays L.) is an economically vital grain crop that is cultivated worldwide. In 2011, a maize foliar disease was detected in Lingtai and Lintao counties in Gansu Province, China. The characteristic signs and symptoms of this disease include irregular chlorotic lesions on the tips and edges of infected leaves and black punctate fruiting bodies in dead leaf tissues. Given favourable environmental conditions, this disease spread to areas surrounding Gansu. In this study, infected leaves were collected from Gansu and Ningxia Hui Autonomous Region between 2018and 2020 to identify the disease-causing pathogen. Based on morphological features, pathogenicity tests, and multilocus phylogenetic analysis involving internal transcribed spacer(ITS), 18S small subunit rDNA(SSU), 28S large subunit rDNA(LSU), translation elongation factor 1-alpha(TEF), and β-tubulin(TUB) sequences, Eutiarosporella dactylidis was identified as the causative pathogen of this newly discovered leaf blight. Furthermore, an in vitro bioassay was conducted on representative strains using six fungicides, and both fludioxonil and carbendazim were found to significantly inhibit the mycelial growth of E. dactylidis. The results of this study provide a reference for the detection and management of Eutiarosporella leaf blight.

中国阿尔茨海默病早期预防指南(2024)

阿尔茨海默病是一种病因复杂的严重智力致残疾病,目前尚无有效的治疗方法。我国是世界上老年人口最多、增长最快的国家之一,也是阿尔茨海默病发病率较高的国家。因此,如何早期预防阿尔茨海默病的发生,是现今健康领域最重要的课题之一。我们在国内外相关研究的基础上,通过文献循证、干预研究实践、案例分析、经验总结和专家咨询,结合中国老年健康和社会文化特点,体现中国传统医学、武术、养生以及社区组织优势,制订出具有中国特色的阿尔茨海默病早期预防指南,涵盖了个人、家庭和社会三个层面的预防策略,从积极生活态度、社会活动参与、认知训练、体育锻炼、戒烟限酒、营养、睡眠,血压、血糖、血脂管理,体重和其他慢病管理以及中医开展针对阿尔茨海默病的一级预防。本指南仅供个人、家庭和社会开展阿尔茨海默病预防时参考。

Revealing the microstructures of metal halide perovskite thin films via advancedtransmission electron microscopy

Metal halide perovskites (MHPs) are excellent semiconductors that have led to breakthroughs in applications in thinfilmsolar cells, detectors, and light-emitting diodes due to their remarkable optoelectronic properties and defect tolerance.However, the performance and stability of MHP-based devices are significantly influenced by their microstructures includingthe formation of defects, composition fluctuations, structural inhomogeneity, etc. Transmission electron microscopy(TEM) is a powerful tool for direct observation of microstructure at the atomic-scale resolution and has been used to correlatethe microstructure and performance of MHP-based devices. In this review, we highlight the application of TEMtechniques in revealing the microstructures of MHP thin films at the atomic scale. The results provide critical understandingof the performance of MHP devices and guide the design of strategies for improving the performance and stability ofMHP devices.

Al/Hf ratio-dependent mechanisms of microstructure and mechanical property of nearly fully dense Al—Hf reactive material

This study proposed three types of Al—Hf reactive materials with particle size ratios(a),which were almost completely dense(porosity of<5.40%)owing to their preparation using hot-pressing technology.Microstructure characteristics and phase composition were analyzed,and the influence of particle size ratios on dynamic mechanical behavior and damage mechanism were investigated.The prepared sample with a=0.1 exhibited continuous wrapping of the Hf phase by the Al phase.Hf—Hf contact(continuous Hf phase)within the sample gradually increased with increasing a,and a small amount of fine Hf appeared for the sample with a=1.The reactive materials exhibited clear strain-rate sensitivity,with flow stressσ0.05and failure strainεfincreasing approximately linearly with increasing strain rate.ε.It is found that the plastic deformation of the material increased with increasing strain rate.As a increased from 0.1 to 1,the flow stress gradually increased.Impact failure of the material was dominated by ductile fracture with a large Al phase plastic deformation band for lower a,while brittle fracture with crushed Hf particles occurred at higher a.Finally,a constitutive model based on BP neural network was proposed to describe the stress-strain relationships of the materials,with an average relative error of 2.22%.

A guidance and control design with reduced information for a dual-spin stabilized projectile

In this paper,an integrated guidance and control method based on an adaptive path-following controller is proposed to control a spin-stabilized projectile with only translational motion information under the constraint of an actuator,uncertainties in aerodynamic parameters and measurements,and control system complexity.Owing to the fairly high rotation speed,the dynamic model of this missile is strongly nonlinear,uncertain and coupled in pitch,yaw and roll channels.A theoretical equivalent resultant force and uncertainty compensation method are comprehensively used to realize decoupling of pitch and yaw.In response to the strong nonlinear and time-varying characteristics of the dynamic system,the quasi-linear model whose parameters are obtained by interpolation of points selected as the segmentation points in the trajectory envelope,is used for calculation in each step.To cope with the system uncertainty caused by model approximation,parameter uncertainty and ballistic interference,an extended state estimator is used to compensate the output feedback according to the test ballistic angle.In order to improve the tracking efficiency and ensure the tracking error convergence with only translational motion information,the virtual guide point,whose derivative is deduced according to the Lyapunov principle,is calculated in real time according to the projection relationship between the real-time position and the reference trajectory,and a virtual line-of-sight angle and the backstepping method are used for the design of the guidance and control system.In order to avoid the influence of control input saturation on the guidance and control performance due to the actuator limitation and improve the robustness of the system,an anti-saturation compensator is designed according to the two-step method.The feasibility and effectiveness of the path-following controller is verified through closed-loop flight simulations with measurement,control,and condition uncertainties.The results indicate that the designed controller can converge to the reference path and evidently decrease the distance between the impact point and target under different uncertainties.

Crack propagation and damage evolution of metallic cylindrical shells under internal explosive loading

This paper investigates the three-dimensional crack propagation and damage evolution process of metallic column shells under internal explosive loading.The calibration of four typical failure parameters for 40CrMnSiB steel was conducted through experiments and subsequently applied to simulations.The numerical simulation results employing the four failure criteria were compared with the differences and similarities observed in freeze-recovery tests and ultra-high-speed tests.This analysis addressed the critical issue of determining failure criteria for the fracture of a metal shell under internal explosive loads.Building upon this foundation,the damage parameter D_(c),linked to the cumulative crack density,was defined based on the evolution characteristics of a substantial number of cracks.The relationship between the damage parameter and crack velocity over time was established,and the influence of the internal central pressure on the damage parameter and crack velocity was investigated.Variations in the fracture modes were found under different failure criteria,with the principal strain failure criterion proving to be the most effective for simulating 3D crack propagation in a pure shear fracture mode.Through statistical analysis of the shell penetration fracture radius data,it was determined that the fracture radius remained essentially constant during the crack evolution process and could be considered a constant.The propagation velocity of axial cracks ranged between 5300 m/s and 12600 m/s,surpassing the Rayleigh wave velocity of the shell material and decreasing linearly with time.The increase in shell damage exhibited an initial rapid phase,followed by deceleration,demonstrating accelerated damage during the propagation stage of the blast wave and decelerated damage after the arrival of the rarefaction wave.This study provides an effective approach for investigating crack propagation and damage evolution.The derived crack propagation and damage evolution law serves as a valuable reference for the development of crack velocity theory and the construction of shell damage evolution modes.

Dynamics modeling and optimal control for multi-information diffusion in Social Internet of Things

As an ingenious convergence between the Internet of Things and social networks,the Social Internet of Things(SIoT)can provide effective and intelligent information services and has become one of the main platforms for people to spread and share information.Nevertheless,SIoT is characterized by high openness and autonomy,multiple kinds of information can spread rapidly,freely and cooperatively in SIoT,which makes it challenging to accurately reveal the characteristics of the information diffusion process and effectively control its diffusion.To this end,with the aim of exploring multi-information cooperative diffusion processes in SIoT,we first develop a dynamics model for multi-information cooperative diffusion based on the system dynamics theory in this paper.Subsequently,the characteristics and laws of the dynamical evolution process of multi-information cooperative diffusion are theoretically investigated,and the diffusion trend is predicted.On this basis,to further control the multi-information cooperative diffusion process efficiently,we propose two control strategies for information diffusion with control objectives,develop an optimal control system for the multi-information cooperative diffusion process,and propose the corresponding optimal control method.The optimal solution distribution of the control strategy satisfying the control system constraints and the control budget constraints is solved using the optimal control theory.Finally,extensive simulation experiments based on real dataset from Twitter validate the correctness and effectiveness of the proposed model,strategy and method.

Selection and application of four QTLs for grain protein content in modern wheat cultivars

The grain protein content(GPC)is the key parameter for wheat grain nutritional quality.This study conducted a resampling GWAS analysis using 406 wheat accessions across eight environments,and identified four previously reported GPC QTLs.An analysis of 87 landraces and 259 modern cultivars revealed the loss of superior GPC haplotypes,especially in Chinese cultivars.These haplotypes were preferentially adopted in different agroecological zones and had broad effects on wheat yield and agronomic traits.Most GPC QTLs did not significantly reduce yield,suggesting that high GPC can be achieved without a yield penalty.The results of this study provide a reference for future GPC breeding in wheat using the four identified QTLs.

Generative adversarial networks based motion learning towards robotic calligraphy synthesis

Robot calligraphy visually reflects the motion capability of robotic manipulators.While traditional researches mainly focus on image generation and the writing of simple calligraphic strokes or characters,this article presents a generative adversarial network(GAN)-based motion learning method for robotic calligraphy synthesis(Gan2CS)that can enhance the efficiency in writing complex calligraphy words and reproducing classic calligraphy works.The key technologies in the proposed approach include:(1)adopting the GAN to learn the motion parameters from the robot writing operation;(2)converting the learnt motion data into the style font and realising the transition from static calligraphy images to dynamic writing demonstration;(3)reproducing high-precision calligraphy works by synthesising the writing motion data hierarchically.In this study,the motion trajectories of sample calligraphy images are firstly extracted and converted into the robot module.The robot performs the writing with motion planning,and the writing motion parameters of calligraphy strokes are learnt with GANs.Then the motion data of basic strokes is synthesised based on the hierarchical process of‘stroke-radicalpart-character’.And the robot re-writes the synthesised characters whose similarity with the original calligraphy characters is evaluated.Regular calligraphy characters have been tested in the experiments for method validation and the results validated that the robot can actualise the robotic calligraphy synthesis of writing motion data with GAN.

2023中国阿尔茨海默病数据与防控策略

本报告汇总了阿尔茨海默病及痴呆相关领域现有的最新数据,分析了我国阿尔茨海默病的流行病学、疾病负担、诊断治疗、风险因素、康复护理和疾病筛查等各方面的现状、问题以及趋势,针对目前中国民众和政策制定者最关心的问题,例如:阿尔茨海默病基本数据是怎样的?为什么知晓率相对提高,但是患者就诊愿望相对不高?如何采用有效的措施来应对,等等,提出了目前阿尔茨海默病的防控策略。特别强调了要大力开发经过验证的早期筛查和诊断工具,提供更有效治疗的创新药物,以及鼓励和建立全国性属地化社会互助支持网络。本报告期望能对医学专业人士、患者、家属和照护者、政府政策制定人员、养老机构等有所帮助,能为阿尔茨海默病的防治工作提供支撑,为相关卫生政策的制定提供依据和建议,有助于提高公众对阿尔茨海默病的认识,以期缓解我国阿尔茨海默病疾病的整体负担,推动我国健康老龄化的实现。

基于标准加入法和多水平的药代动力学综合分析疏血通注射液中不稳定的次黄嘌呤(潜在的质量标志物)

[目的]作为一种中药注射制剂,舒血通注射液用于治疗缺血性脑卒中。次黄嘌呤是其潜在的质量标志物之一。本研究的目的是通过对次黄嘌呤的定量和药代动力学行为分析为疏血通注射液的质量控制奠定基础。[方法]应用液相色谱-串联质谱(LC-MS/MS)首次建立了基于标准加入法的疏血通注射液中次黄嘌呤的定量方法。另一方面,也成功建立了基于LC-MS/MS的大鼠给药后血浆样品中次黄嘌呤的测定方法。[结果]对于相同批次的疏血通注射液,采用常规的液质联用技术测出的次黄嘌呤的浓度大于LC-MS/MS联合标准加入法测出的次黄嘌呤的浓度。单次静脉注射疏血通注射液的低、中、高剂量比为1:2:4,AUC0-t分别为(848.34±324.53)μg·h/L、(1483.94±497.74)μg·h/L,(3074.84±910.29)μg·h/L,剂量呈良好的线性依赖关系。[结论]标准加入法的引入可校正目标化合物的浓度,进而消除内源性物质的影响。别嘌呤出可抑制次黄嘌呤的转化以保证药代动力学研究中检测的准确性。通过空白血浆前处理获得的“空白生物基质”成功区分了内源性和药源性的次黄嘌呤。静脉注射次黄嘌呤血药浓度与给药剂量呈良好的线性关系。同样,多次给药中剂量组也没有药物蓄积,这与单次给药中剂量组的药代动力学特征是相似的。

Temperature field model in surface grinding: a comparative assessment

Grinding is a crucial process in machining workpieces because it plays a vital role in achieving the desired precision and surface quality.However,a significant technical challenge in grinding is the potential increase in temperature due to high specific energy,which can lead to surface thermal damage.Therefore,ensuring control over the surface integrity of workpieces during grinding becomes a critical concern.This necessitates the development of temperature field models that consider various parameters,such as workpiece materials,grinding wheels,grinding parameters,cooling methods,and media,to guide industrial production.This study thoroughly analyzes and summarizes grinding temperature field models.First,the theory of the grinding temperature field is investigated,classifying it into traditional models based on a continuous belt heat source and those based on a discrete heat source,depending on whether the heat source is uniform and continuous.Through this examination,a more accurate grinding temperature model that closely aligns with practical grinding conditions is derived.Subsequently,various grinding thermal models are summarized,including models for the heat source distribution,energy distribution proportional coefficient,and convective heat transfer coefficient.Through comprehensive research,the most widely recognized,utilized,and accurate model for each category is identified.The application of these grinding thermal models is reviewed,shedding light on the governing laws that dictate the influence of the heat source distribution,heat distribution,and convective heat transfer in the grinding arc zone on the grinding temperature field.Finally,considering the current issues in the field of grinding temperature,potential future research directions are proposed.The aim of this study is to provide theoretical guidance and technical support for predicting workpiece temperature and improving surface integrity.

核心稳定性训练对散打运动员鞭腿连击能力的影响

本研究采用文献资料,实验法、数理统计法,进行为期四周的核心稳定性力量训练,散打运动员的鞭腿连击能力有显著性提高,分析和探讨得到以下结论:鞭腿作为散打项目重要的腿法技术之一,掌握鞭腿技术动力链肌群的解剖学、生理学、生物力学特点,有助于以后训练中鞭腿动作协调和发挥力点的最大化。通过核心稳定性力量训练,散打鞭腿连击能力得到提高,核心区力量加强,柔韧性提高。以核心区腰--髋关节--骨盆肌群的稳定性训练和周围小肌肉群力量的加强,对于鞭腿支撑腿的稳定性,鞭打腿力的传递和击打目标的准确性得到显著提高。通过加强核心肌群力量的稳定性的训练,有助于防止散打项目中常出现的伤痛病症和运动损伤,同时对于康复陈旧性损伤具有良好的效果。

产学结合视域下职业教育PQM体系研究

要想提升职业院校的教学质量,产学结合是有着显著效果的一个办法。产学结合不仅提升了职业院校整体的教学质量,还增添了许多教育教学组织形式。它在原有的教学基础上加大了难度,使得学校在管理方面遇到了瓶颈。职业院校要想维持高质量的教育教学活动,建立有秩序有效果的管理体系是必不可少的。本文章将为大家详细分析职业院校在融合产学结合后教学管理体系出现的问题,并同时为这些问题提出一系列解决方案,同时为提升职业院校整体教学质量,为社会各方面培养人才提出一些有利的建议,如提升师生考核难度、加强质量控制体系的建设、推进“双师型”教师队伍的组成等。

Plasma metabolomics identifies metabolic alterations associated with the growth and development of cat

Background:The purpose of our study was to study the composition and content of the feline plasma metabolome revealing the critical metabolites and metabolic pathways associated with age during growth and development.Methods:Blood samples were collected from juvenile and adult groups for blood routine tests and serum biochemistry tests.Non-targeted metabolomics analyses of plasma were also performed to investigate changes in metabolites and metabolic pathways.Results:In this study,we found that the red blood cell counts,liver function indexes(albumin and gamma-glutamyl transpeptidase),and the concentration of triglyceride and glucose changed significant with growth and development.The metabolomics results revealed that 1427 metabolites were identified in the plasma of young and adult cats.Most of these metabolites belong to major classes of lipids and lipid-like molecules.The most obvious age-related metabolites include reduced levels of chenodeoxycholate,taurocholate,cholate,and taurochenodeoxycholate but increased levels of L-cysteine and taurocyamine in the adult cat's serum.These metabolites are mainly involved in the primary bile acid biosynthesis pathway,the bile secretion pathway,and the taurine and hypotaurine metabolism pathway.Conclusion:This study revealed many age-related metabolite alterations in the feline plasma.These age-varying metabolites,especially in the bile acid biosynthesis and secretion metabolism pathways,indicate that the regulation of these pathways is involved in the growth and development of cats.This study promotes our understanding of the mechanism of feline growth and provides new insights into nutrition and medicine for cats of different ages.

基础无机化学实验课程思政的探索与实践——以氧化型石墨烯制备实验为例

在中国高等教育剧烈变革的时代,作为化学专业及相关专业大学一年级学生入校后开设的第一门实验课,在无机化学实验课的教学过程中对学生进行全方位的培养,注重教学思政,对于提升实验操作技能、夯实学生基础理论知识、激发学生爱国情怀、认识科学发展客观规律以及开拓思维创新等方面有着至关重要的作用。本文以氧化型石墨烯制备实验为例,探讨了如何在实验教学中引入思政元素,使学生在提高科学研究能力的同时,充分认识科学研究在强国中的重要性,培养学生科技报国的理念。

地下水位变化对透-阻型岩溶塌陷影响的分析

文章从一维地下水运动和渗透力学的角度,分析比较潜水位上升与承压水位下降对岩溶地区透—阻型盖层中阻水层渗透稳定性的影响,重点讨论了承压水位下降速度(降速)与下降深度(降深)对阻水层中渗透坡降的影响,结果表明:地下水位变化(潜水位上升或承压水位下降)产生的非稳定渗流不利于岩溶洞穴开口上方阻水层的稳定,承压水位的下降对岩溶开口附近处阻水层中渗透力的影响远大于潜水位的变化;在承压层水位最大降深确定的条件下,承压水位下降速度愈快,岩溶开口附近处阻水层中向下渗透力愈大。因此,在覆盖型岩溶地区抽取地下水时,为了减缓或避免覆盖型塌陷的发生,应同时控制好最大降深和最大开采速度。

2022年中国阿尔茨海默病知晓与需求现状调查

目的:为了更加全面了解我国老年性痴呆(阿尔茨海默病)防治工作的现状及发展趋势,更加精准地为防治工作提供政策咨询及对策建议,开展了本次阿尔茨海默病知晓与需求现状调查。对象与方法:通过线上问卷,对18岁以上普通成年居民进行调查,居民来自全国各个省市自治区和港澳台地区,调查总样本为20671人。结果:被调查人群阿尔茨海默病的总知晓率为95.9%,经统计学标化后为91.5%。不同人群对阿尔茨海默病的总知晓率存在一定差异;认为阿尔茨海默病或老年痴呆病可以预防的比例是87.9%;被调查居民觉得居家照护患者遇到的困难最主要表现在精力不够、照护能力不足和缺少专业的失智养老服务机构;患者的最主要的照护者是配偶,占47.9%,对阿尔茨海默病康复治疗内容了解的仅占23.3%;对合理安排患者营养知晓率为39%,在被调查人群中,主动愿意去医院就诊的比例只有12.9%,其中农村居民和低学历居民主动就诊愿望较低。结论:本次调查结果为更加精准地制定阿尔茨海默病防治对策,提供了重要的科学依据。