260例持续性姿势-知觉性头晕患者中医体质与发病因素的相关性分析

目的 探讨中医体质与持续性姿势-知觉性头晕(persistent postural-perceptual dizziness, PPPD)发病的相关性。方法:收集2019年1月-2022年3月医院收治的260例PPPD患者为研究对象,根据《中医体质分类与判定》量表对260例PPPD患者进行中医体质评定,应用SPSS 25.0软件进行统计学分析,探讨PPPD患者的中医体质分布规律。结果 PPPD患者中医体质类型依次为:气郁质(35.8%)>痰湿质(29.6%)>气虚质(10%)>湿热质(7.7%)>阴虚质(6.5%)=血瘀质(6.5%)>阳虚质(3.8%)。患者体质分布在性别间存在统计学差异(P=0.033<0.05),男性患者常见体质为:气郁质、痰湿质,女性患者常见体质为:气郁质、痰湿质。结论 PPPD患者中医常见体质类型为气郁质、痰湿质,其体质类型分布与性别有相关性,好发于女性,气郁质女性偏多,痰湿质男性偏多。

熔融制片-X射线荧光光谱法测定碳酸盐岩石中主次量元素

采用四硼酸锂和偏硼酸锂2:1混合溶剂熔融制备样片,Zetium X射线荧光光谱仪测定碳酸盐岩石中氧化铝、氧化钙、氧化铁、氧化钾、氧化镁、氧化钠、氧化钡、五氧化二磷、三氧化硫、二氧化硅、二氧化钛、氧化锰等12种组分。重点研究了熔样比、熔样方式、测定条件、基体干扰矫正等,经有证标准物质验证,分析方法的精密度满足DZ/T0130《地质矿产实验室测试质量管理规范》,结果与标准值一致。

健神利水颗粒联合呋塞米治疗脑出血继发性脑水肿的临床研究

目的探讨健神利水颗粒联合呋塞米治疗脑出血继发性脑水肿的临床效果。方法选取2017年4月—2020年4月广西中医药大学第一附属医院收治的脑出血继发性脑水肿患者100例,根据随机数字表法将其分为对照组和研究组,每组各50例。对照组给予呋塞米治疗,研究组在对照组的基础上联合健神利水颗粒治疗,两组均治疗14 d。比较两组疗效、美国国立卫生研究院卒中量表(NIHSS)评分、超敏C反应蛋白(hs-CRP)、S-100β蛋白、白细胞介素-1β(IL-1β)、血肿体积、脑水肿体积、收缩期峰值血流速度、平均血流速度、脑血流量及不良反应发生情况。结果研究组临床总有效率高于对照组,差异有统计学意义(P<0.05)。两组治疗后NIHSS评分均较治疗前下降,且研究组低于对照组,差异均有统计学意义(均P<0.05)。两组治疗后平均血流速度、收缩期峰值血流速度、脑血流量均较治疗前升高,且研究组高于对照组,差异均有统计学意义(均P<0.05)。两组治疗后hs-CRP、S-100β蛋白、IL-1β均较治疗前降低,且研究组低于对照组,差异均有统计学意义(均P<0.05)。两组治疗后血肿体积、脑水肿体积均较治疗前缩小,且研究组小于对照组,差异均有统计学意义(均P<0.05)。两组不良反应发生率比较,差异无统计学意义(P>0.05)。结论健神利水颗粒联合呋塞米治疗脑出血继发性脑水肿,可促进血肿体积、脑水肿体积缩小,改善脑部血流,降低脑组织炎症反应及过氧化损伤,减轻脑组织损伤,疗效肯定。

不同栽培模式对油茶林下多花黄精生长的影响

采用多花黄精根茎繁殖苗在油茶林下开展不同栽培模式种植效果比较。结果表明:在容器、大田和油茶林下三种栽培模式下,多花黄精平均株高和平均地径大小为:容器>大田>林下,且容器栽培显著高于大田和油茶林下栽培,平均块茎鲜重大小为:容器>林下>大田,容器和油茶林下显著高于大田栽培。三种栽培模式对多花黄精地下块茎多糖、黄酮和薯蓣皂苷元等活性成分含量大小均为:林下>大田>容器,且林下栽培显著高于大田和容器栽培。三种不同油茶密度对多花黄精地径、株高和根茎鲜重影响均为:D1>D2>D3,其中平均株高D1显著高于D2和D3,D1根茎鲜重显著高于D3。不同坡位对多花黄精生长有一定影响,株高下坡位>上坡位>中坡位。

不同基质对浙江樟幼苗生长及养分吸收的影响

浙江樟(Cinnamomum chekiangense)是重要的珍贵树种,在大力推广珍贵树种造林中,优质容器苗的培育是造林成功的关键,而育苗基质直接决定着苗木质量。本文以浙江樟1年生苗为研究对象,采用盆栽的方法,研究5种不同配比基质(黄泥、锯末、泥炭)对苗木株高、地径、生物量的生长和氮磷钾养分积累的影响,旨在筛选出适合浙江樟容器苗培育的基质配比,为优质容器苗的培育提供基础。结果表明A3(黄心土︰泥炭︰锯末=40︰30︰30)基质最有利于浙江樟的生长,株高和地径均显著高于A5(P<0.05);A3基质培育的浙江樟叶片、枝干、根系和总生物量均为最大,分别为33.63,39.57,48.43,121.64 g·株^(−1),显著高于其他处理(P<0.05);浙江樟全株氮、磷、钾积累量以A3基质为佳,分别为3168.8,137.3,673.1 mg·株^(−1);灰色关联度法评价表明,A3基质是浙江樟容器苗生长的最优基质。

多普勒差分干涉仪干涉图畸变对相位反演精度影响分析

为了解决多普勒差分干涉仪风场探测技术中,干涉图畸变对风速反演带来的系统误差,通过对大气气辉氧原子红线和绿线的正演干涉图添加不同类型、大小的干涉图畸变,仿真对比了含畸变干涉图与理想干涉图反演多普勒相位的差异,得到干涉图畸变对多普勒相位反演精度的影响。结果表明多普勒相位误差随着目标风场与干涉图畸变程度增大而增大,其中条纹局部弯曲影响最大,且弯曲范围越小越靠近采样中心误差越大。通过局部弯曲对不同条纹频率系统产生的误差仿真表明,等量的弯曲对条纹频率高的系统产生更大影响。此外含畸变干涉图多行像元合并时局部调制度降低,不会增加相位不确定度,因此即使干涉图存在缺陷也可以进行多行像元合并,提高信噪比,降低相位不确定度。研究结果为多普勒差分干涉仪的设计、加工、装调指标提供了定量理论依据。

Path planning and stability control of collision avoidance system based on active front steering

Vehicle collision avoidance system is a kind of auxiliary driving system based on vehicle active safety,which can assist the driver to take the initiative to avoid obstacles under certain conditions,so as to effectively improve the driving safety of vehicle.This paper presents a collision avoidance system for an autonomous vehicle based on an active front steering,which mainly consists of a path planner and a robust tracking controller.A path planner is designed based on polynomial parameterization optimized by simulated annealing algorithm,which plans an evasive trajectory to bypass the obstacle and avoid crashes.The dynamic models of the AFS system,vehicle as well as the driver model are established,and based on these,a robust tracking controller is proposed,which controls the system to resist external disturbances and work in accordance with the planning trajectory.The proposed collision avoidance system is testified through CarSim and Simulink combined simulation platform.The simulation results show that it can effectively track the planning trajectory,and improve the steering stability and anti-interference performance of the vehicle.

Stability control of steer by wire system based on μ synthesis robust control

The uncertainty influences may result in performance deterioration and instability to the steer by wire(SBW) system. Thus, it must make the control system keep robust stability from uncertainty, and have good robustness. In order to effectively restrain the interference and improve steering stability, this paper presents a μ synthesis robust controller based on SBW system, which considers the effect of model uncertainty and external disturbance on the system dynamics. Taking the ideal yaw rate tracking, interference suppression and excellent robustness as the control objectives, the μ synthesis robust controller is designed using linear fractional transformation theory to deal with the uncertainty. Then, it is testified through time domain and robustness simulation analysis. Simulation results show that the proposed controller can not only ensure robustness and robust stability of the system quite well, but improve handling stability of the vehicle effectively. The results of this study provide certain theoretical basis for the research and application of SBW system.

Robust control for active suspension system under steering condition

To minimize the auto body's posture change caused by steering and uneven road, and improve the vehicle's riding comfort and handling stability, this paper presents an H∞ robust controller of the active suspension system, which considers the effects of different steering conditions on its dynamic performance. The vehicle's vibration in the yaw, roll, pitch and vertical direction and the suspension's dynamic deflection in the steering process are taken into account for the designed H∞ robust controller, and it introduces the frequency weight function to improve the riding comfort in the specific sensitive frequency bands to human body. The proposed robust controller is testified through simulation and steering wheel angle step test. The results show that the active suspension with the designed robust controller can enhance the anti-roll capability of the vehicle, inhibit the changes of the body, and improve the riding comfort of the vehicle under steering condition. The results of this study can provide certain theoretical basis for the research and application of active suspension system.

Change patterns of oncomelanid snail burden in areas within the Yangtze River drainage after the three gorges dam operated

Background:An"integrated control"strategy has been implemented within seven provinces at highest risk for schistosomiasis along Yangtze River in Peoples'Republic of China(P.R.China)since 2004.Since O ncom elania hupensis is the only intermediate host of the blood fluke(Schistosom a japonicum),controlling the distribution of snails is considered an essential and effeaive way to reduce the risk of schistosomiasis infection.The study aimed to determine the snail area burden and annual trend among provinces with potential risk for schistosomiasis along the Yangtze River,above and below the Three Gorges Dam(TGD).Methods:This retrospective study utilized data previously collected from the National Parasitic Diseases Control Information Management System(NPDCIMS)on annual snail surveys from 2009 to 2017.Descriptive statistics were performed for analyzing the snail burden by provinces,counties,type of environmental location and year,and mapping was conducted to present the snails distribution.Results:From 2009 to 2017,the total snail infested area decreased by 4.22%,from 372253 hm^2 to 356553 hm^2 within the seven high risk provinces.The majority of snails were found in the marshland and lake regions,outside of control embankments.The total snail burden trend remained relatively stable in upstream regions above the TGD from 2010 to 2015,while the trend decreased within downstream regions during this period.In 2016 and 2017,the total snail burden trend increased in both upstream and downstream provinces,however,upstream saw a larger increase.From 2009 to 2017,there were a total of 5990 hm^2 of newly developed snail areas in the seven study provinces and the majority were concentrated in regions below the TGD,accounting for 5610 hm^2(93.70%).Conclusions:There has been a decline in total snail counts from 2009 to 2017.Meanwhile,new snail breeding areas were formed mainly within provinces downstream the TGD due to spread of snails,indicated that the oncomelanid snail would be difficult to completely eliminate.We suggest that the national schistosomiasis integrated control strategy,including mollusciding and environmental modification,will need to be enhanced significantly going forward to achieve a greater reduaion in snail burden and ultimately to achieve elimination.

An enhanced hybrid and adaptive meta-model based global optimization algorithm for engineering optimization problems

Due to the good balance between high efficiency and accuracy, meta-model based optimization algorithm is an important global optimization category and has been widely applied. To better solve the highly nonlinear and computation intensive en- gineering optimization problems, an enhanced hybrid and adaptive meta-model based global optimization （E-HAM） is first proposed in this work. Important region update method （IRU） and different sampling size strategies are proposed in the opti- mization method to enhance the performance. By applying self-moving and scaling strategy, the important region will be up- dated adaptively according to the search results to improve the resulting precision and convergence rate. Rough sampling strategy and intensive sampling strategy are applied at different stages of the optimization to improve the search efficiently and avoid results prematurely gathering in a small design space. The effectiveness of the new optimization algorithm is verified by comparing to six optimization methods with different variables bench mark optimization problems. The E-HAM optimization method is then applied to optimize the design parameters of the practical negative Poisson＇s ratio （NPR） crash box in this work. The results indicate that the proposed E-HAM has high accuracy and efficiency in optimizing the computation intensive prob- lems and can be widely used in engineering industry.

Parametric design strategy of a novel cylindrical negative Poisson's ratio jounce bumper for ideal uniaxial compression load-displacement curve

A cylindrical negative Poisson's ratio(CNPR) structure based on two-dimensional double-arrow negative Poisson's ratio(NPR)structure was introduced in this paper. The CNPR structure has excellent stiffness, damping and energy absorption performances,and can be applied as spring, damper and energy absorbing components. In this study, the CNPR structure was used as a jounce bumper in vehicle suspension, and the load-displacement curve of NPR jounce bumper was discussed. Moreover, the influences of structural parameters and materials on the load-displacement curve of NPR jounce bumper were specifically researched. It came to the conclusion that only the numbers of cells and layers impact the hardening displacement of NPR jounce bumper. And all parameters significantly affect the structure stiffness at different displacement periods. On the other hand, the load-displacement curve of NPR jounce bumper should be in an ideal region which is difficult to be achieved applying mathematical optimization method. Therefore, a parametric design strategy of NPR jounce bumper was proposed according to the parametric analysis results. The design strategy had two main steps: design of hardening displacement and design of stiffness. The analysis results proved that the proposed method is reliable and is also meaningful for relevant structure design problem.

The “1-3-7” Approach to Malaria Surveillance and Response--Henan Province, China, 2012−2018

What is already known about this topic?The“1-3-7”approach to malaria surveillance and response was a key measure for malaria elimination in China and was first introduced into the World Health Organization(WHO)as an international guideline for malaria surveillance and response in 2018.What is added by this report?The“1-3-7”approach was well implemented in Henan Province from 2012−2018.Over this study period,a total of 1,294 malaria cases were detected and reported,and all cases were diagnosed and reported within 1 day with 99.23%(1,284/1,294)of cases were investigated within 3 days.In addition,93.7%(1,212/1,294)of foci were investigated and vector control was implemented within 7 days at all residual non-active foci to prevent further spread.What are the implications for public health practice?The“1-3-7”controlling pattern would be an effective and approachable method for implementation especially in malaria-eliminating countries and regions,but the interval from symptom onset to diagnosis cannot be ignored.Thus,the roles and responsibilities that all actors involved in the health sector must be specified too.

Fabrication of virus-like particles with strip-pattern surface：A two-step self-assembly approach

Spherical nanostructures with striped patterns on the surfaces resembling the essential structures of natural virus particles were constructed through a two-step self-assembly approach of polystyrene-boligo（acrylic acid）（PS-b-oligo-AA） and poly（γ-benzyI L-glutamate）-b-poly（ethylene glycol）（PBLG-bPEG） copolymer mixtures in solution.On the basis of difference in hydrophilicity and self-assembly properties of the two copolymers,the two-step self-assembly process is realized.It was found that PS-boligo-AA copolymers formed spherical aggregates by adding a certain amount of water into polymer solutions in the first step.In the second step,two polymer solutions were mixed and water was further added,inducing the self-assembly of PBLG-b-PEG on the surfaces of PS-b-oligo-AA spheres to form striped patterns.In-depth study was conducted for the indispensable defects of striped patterns which are dislocations and ＋1/2 disclinations.The influencing factors such as the mixing ratio of two copolymers and the added water content in the first step on the morphology and defects of the striped patterns were investigated.This work not only presents an idea to interpret mechanism of the cooperative self-assembly behavior,but also provides an effective approach to construct virus-like particles and other complex structures with controllable morphology.

A new Timoshenko beam model for simulation of mechanical system with large deformation

Beam model has been used widely in computer aided engineering for mechanical systems and the simulation results largely depend on the beam model, there are great demand for beam model with high accuracy and efficiency in simulating the mechanical system with large deformation. In this work, a new model of Timoshenko beam for large deformations is proposed to improve the accuracy and efficiency. Absolute nodal coordinate formulation and geometrically-exact beam formulation, which make the model very suitable to simulate large deformation mechanical system, are first combined in the new beam model, the governing equations are then discrete by finite element methods and numerical difficulties are well solved by applying the shape function strategy. The new beam model is then applied to simulate the mechanical systems with large deformation and the simulations based on the traditional beam model and hexahedron element were also carried out to verify the results. The results show that good precision and efficiency in simulating the mechanical systems with large deformation can be obtained by the new Timoshenko beam model at the same time. The presented new method also serves as a good foundation for other simulation of mechanical systems.

Multi-objective robust design optimization of a novel negative Poisson's ratio bumper system

Negative Poisson's ratio(NPR) structure has outstanding performances in lightweight and energy absorption, and it can be widely applied in automotive industries. By combining the front anti-collision beam, crash box and NPR structure, a novel NPR bumper system for improving the crashworthiness is first proposed in the work. The performances of the NPR bumper system are detailed studied by comparing to traditional bumper system and aluminum foam filled bumper system. To achieve the rapid design while considering perturbation induced by parameter uncertainties, a multi-objective robust design optimization method of the NPR bumper system is also proposed. The parametric model of the bumper system is constructed by combining the full parametric model of the traditional bumper system and the parametric model of the NPR structure. Optimal Latin hypercube sampling technique and dual response surface method are combined to construct the surrogate models. The multi-objective robust optimization results of the NPR bumper system are then obtained by applying the multi-objective particle swarm optimization algorithm and six sigma criteria. The results yielded from the optimizations indicate that the energy absorption capacity is improved significantly by the NPR bumper system and its performances are further optimized efficiently by the multi-objective robust design optimization method.