股骨颈动力交叉钉系统主钉位置对股骨颈骨折稳定性影响的有限元分析

目的采用有限元方法分析股骨颈动力交叉钉系统(FNS)中主钉位置对PauwelsⅢ型股骨颈骨折稳定性的影响。方法选择1名25岁健康男性志愿者,CT扫描收集其股骨中上段影像学数据并建立PauwelsⅢ型股骨颈骨折三维模型,同时建立FNS模型,将两种模型组合并根据FNS主钉位置的不同得到模型1(FNS主钉置入点位于股骨颈轴位中前1/3)、模型2(FNS主钉置入点位于股骨颈轴位中心)、模型3(FNS主钉置入点位于股骨颈轴位中后1/3)。采用有限元分析法评估并比较每组模型中的股骨颈骨折远端和近端、股骨近端、内固定装置的应力情况,同时分析股骨头远端和近端及内固定装置远端和近端在X(平行于股骨颈轴线)、Y(股骨颈矢状位)、Z(垂直于股骨颈轴线)轴位移情况。结果①3组模型股骨颈骨折端及股骨近端的应力随压力的增加均逐渐增加,3组模型间应力比较差异无统计学意义(P>0.05)。②随着压力的增加内固定装置的应力逐渐增加,模型1及模型2均小于模型3(P<0.05)。③3组模型不同压力下股骨头远、近端以及内固定装置远、近端在X轴及Z轴方向位移比较差异均无统计学意义(P>0.05);在Y轴方向位移中,模型3均大于模型1和模型2(P<0.05),模型1与模型2比较差异均无统计学意义(P>0.05)。结论FNS主钉置入点位于股骨颈轴位中心及偏前具有较好的抗旋转能力且能避免内固定装置应力集中,从而使股骨颈骨折固定更牢靠。

对不同构型空心拉力钉影响PauwelsⅢ型股骨颈骨折稳定性的有限元分析

目的 采用三维有限元方法对3种不同空心拉力螺钉构型治疗PauwelsⅢ型股骨颈骨折的稳定性进行分析。方法 选择来自山东省泰安市第一人民医院骨科的1名25岁健康男性志愿者,行股骨近端CT薄层扫描,利用医学三维重建软件Mimics 19.0、Geomagic Wrap 2017软件、Solidworks 2017软件建立PauwelsⅢ型股骨颈骨折三维模型。构建三种不同排布方式的内固定空心螺钉固定模型:三枚空心螺钉倒三角平行植入(模型1),三枚空心螺钉倒三角头端外展植入(模型2)和三枚空心螺钉倒三角头端内聚植入(模型3)。在ANSYS 17.0有限元软件中进行不同模型应力大小的数据计算,分析各模型中股骨颈骨折断端及股骨近端应力分布情况、应力值大小和不同平面的位移情况,从而分析不同类型固定情况下骨折断端的稳定性。结果 模型2中股骨颈骨折远近端应力差值最大,模型1最小。模型3中股骨头可承受压力最小,模型1与模型2无明显差距。模型2中内固定物平均应力随压力增加其应力增加幅度最小。不同压力条件下模型2在不同轴线的位移较其他两种模型小。结论 3枚空心螺钉不同构型植入治疗PauwelsⅢ型股骨颈骨折时,外展植钉分布表现出来良好的支撑、抗内翻、抗旋转应力作用,但滑动加压作用较平行植钉时差,内聚植钉时骨折整体稳定性最差。因此,空心钉治疗股骨颈骨折时并非必须平行植入,但应避免螺钉内聚型植入。

Discussion on Scaffolding Teaching Mode of Traditional Chinese Medicine under the Background of Internet

This study was conducted to explore the construction of scaffolding teaching mode of Traditional Chinese Medicine under the background of"Internet+".The students of Grade 2018 majoring in traditional Chinese medicine were selected as the object,and some chapters of the textbook of traditional Chinese medicine were selected and taught by the traditional teaching mode while interspersing the scaffolding teaching mode,in order to help the implementation of the scaffolding teaching model.We adopted the methods of setting up situational scaffolding,question scaffolding and guide scaffolding to carry out relevant teaching contents.The scaffolding instruction model has a good degree of participation,and to a certain extent,it stimulates students'self-consciousness and enthusiasm,and improves their ability of analyzing and solving problems and their spirit of innovation.

部队急性上呼吸道感染并发心肌炎患者临床特点及动态心电图监测研究

目的分析急性上呼吸道感染合并心肌炎患者的临床特点,并检测动态心电图。方法收集2012年5月至2017年5月43例上呼吸道感染合并心肌炎的患者,定义为心肌炎组;另选择同期健康体检的40例为对照组,观察两组患者的心功能情况,并分析心肌酶谱和心脏损伤相关指标与对照组的差异。结果急性上呼吸道合并心肌炎的患者主要临床症状为胸闷、胸痛以及呼吸困难。对患者进行心肌酶和心肌损伤标志物的结果显示相关的指标均在发病后1周开始上升然后下降。病毒性心肌炎的患者可以出现多样的心律失常。结论急性上呼吸道感染并发心肌炎早期临床症状不明显,需要提高警惕,采取综合措施监测患者心功能情况,及时治疗防止心源性猝死等严重事件发生。

靶标寄主害虫提取物驯化对松毛虫赤眼蜂寄主选择偏好的影响

柞蚕卵繁育的松毛虫赤眼蜂已被用于防治多种鳞翅目害虫。为改善雌蜂对害虫的嗜好性,本研究以亚洲玉米螟卵、幼虫和雌蛾腹部提取液及正己烷对照溶液,在孤雌产雌品系和两性品系子代蜂幼期及羽化前期施加气味刺激,调查子代雌蜂对玉米螟卵的选择偏好。结果发现,对照组孤雌产雌品系雌蜂对玉米螟卵选择率显著高于两性品系;经提取液驯化的两性品系雌蜂对玉米螟卵选择率显著高于对照;雌蛾腹部提取液处理的两性品系雌蜂对玉米螟卵的选择率和瞬时选择倾向最高,但不同提取液对孤雌产雌品系雌蜂的选择率和瞬时选择倾向无显著影响;提取液和蜂品系对雌蜂卵块驻留时间无显著影响。本研究将为改善寄生蜂对寄主害虫的靶向性提供参考。

从台积电的成长看台湾芯片产业崛起之路

芯片产业的发展关乎下游相关'新经济'的兴衰。本文以台积电的成长路径为案例,通过系统梳理其发展历程,总结出中国台湾地区芯片产业'后发制人'的崛起之路:多维度的产业扶持政策、持续的高强度研发投入、合适的企业'掌舵人'、精准的模式创新、高效的政府基金。

High-Speed EMU TCMS Design and LCC Technology Research

This paper introduces the high-speed electrical multiple unit （EMO） life cycle, including the design, manufacturing, testing, and maintenance stages. It also presents the train control and monitoring system （TCMS） software development platform, the TCMS testing and verification bench, the EMU driving simulation platform, and the EMU remote data transmittal and maintenance platform. All these platforms and benches combined together make up the EMU life cycle cost （LCC） system. Each platform facilitates EMU LCC management and is an important part of the system.

Astrophysical constraints on the proton-to-electron mass ratio with FAST

That the laws of physics are the same at all times and places throughout the Universe is one of the basic assumptions of physics. Astronomical observations provide the only means to test this basic assumption on cosmological time and distance scales. The possibility of variations in the dimensionless physical constant μ-the proton-to-electron mass ratio, can be tested by comparing astronomical measurements of the rest frequency of certain spectral lines at radio wavelengths with laboratory determinations. Different types of molecular transitions have different dependencies on μ and so observations of two or more spectral lines towards the same astronomical source can be used to test whether there is any evidence for either temporal or spatial changes in the physical fundamental constants. μ will change if the relative strength of the strong nuclear force compared to the electromagnetic force varies. Theoretical studies have shown that the rotational transitions of some molecules which have transitions in the frequency range that will be covered by FAST(e.g., CH_3 OH, OH and CH) are sensitive to changes in μ. A number of studies looking for possible variations in μ have been undertaken with existing telescopes, however, the greater sensitivity of FAST means it will open new opportunities to significantly improve upon measurements made to date.In this paper, we discuss which molecular transitions and sources(both in the Galaxy and external galaxies)are likely targets for providing improved constraints on μ with FAST.

A Study on Non-coplanar Baseline Effects for Mingantu Spectral Radioheliograph

As a dedicated solar radioheliograph,the MingantU SpEctral RadioHeliograph(MUSER)has a maximum baseline of more than 3000 m and a frequency range of 400 MHz–15 GHz.According to the classical radio interferometry theory,the non-coplanar baseline effect(i.e.,w-term effect)would be considered and calibrated for such a radio instrument.However,little previous literature made the qualitative or quantitative analyses on w-term effects of solar radioheliograph in-depth.This study proposes a complete quantitative analysis of w-term effects for the MUSER.After a brief introduction of the MUSER,we systematically investigate the baseline variations over a year and analyze the corresponding variations of w-term.We further studied the effects of the w-term in the imaging for the specified extended source,i.e.,the Sun.We discussed the possible effects of the w-term,such as image distortion and so on.The simulated results show that the w-term is an essential and unavoidable issue for solar radio imaging with high spatial resolution.

Fine-grained distributed averaging for large-scale radio interferometric measurement sets

The Square Kilometre Array(SKA)would be the world’s largest radio telescope with eventually over a square kilometre of collecting area.However,there are enormous challenges in its data processing.The use of modern distributed computing techniques to solve the problem of massive data processing in the SKA is one of the most important challenges.In this study,basing on the Dask distribution computational framework,and taking the visibility function integral processing as an example,we adopt a multi-level parallelism method to implement distributed averaging over time and channel.Dask Array was used to implement super large matrix or arrays with supported parallelism.To maximize the usage of memory,we further exploit the data parallelism provided by Dask that intelligently distributes the computational load across a network of computer agents and has a built-in fault tolerance mechanism.The validity of the proposed pattern was also verified by using the Common Astronomy Software Application(CASA),wherein we analyze the smearing effects on images reconstructed from different resolution visibilities.

Periodic variation and phase analysis of grouped solar flare with sunspot activity

Studies on the periodic variation and the phase relationship between different solar activity indicators are useful for understanding the long-term evolution of solar activity cycles.Here we report the statistical analysis of grouped solar flare(GSF) and sunspot number(SN) during the time interval from January 1965 to March 2009.We find that,(1) the significant periodicities of both GSF and SN are related to the differential rotation periodicity,the quasi-biennial oscillation(QBO),and the eleven-year Schwabe cycle(ESC),but the specific values are not absolutely identical;(2) the ESC signal of GSF lags behind that of SN with an average of 7.8 months during the considered time interval,which implies that the systematic phase delays between GSF and SN originate from the inter-solar-cycle signal.Our results may provide evidence about the storage of magnetic energy in the corona.

The Algorithm of Chemical Species Analysis for Ab Intio Molecular Dynamics Simulations and Its Application

In ab initio molecular dynamics(AIMD)simulations of chemical reactions,it is important but difficult to identify the chemical species in the trajectory automatically and quickly.In this paper,based on the chemical graph theory,an algorithm for molecular species identification,according to the molecular coordinates and empirical bond length database,is presented.As an example,the chemical species in condensed glycine at room temperature are investigated with our algorithm in detail.The chemical species,including canonical and zwitterionic glycine,their protonated and de-protonated states,and the free protons,are all identified,counted and recorded correctly.Potential applications and further development of the algorithm are also discussed.

Performance Evaluation of Baseline-dependent Averaging Based on Full-scale SKA1-LOW Simulation

The Square Kilometre Array(SKA)is the largest radio interferometer under construction in the world.Its immense amount of visibility data poses a considerable challenge to the subsequent processing by the science data processor(SDP).Baseline dependent averaging(BDA),which reduces the amount of visibility data based on the baseline distribution of the radio interferometer,has become a focus of SKA SDP development.This paper developed and implemented a full-featured BDA module based on Radio Astronomy Simulation,Calibration and Imaging Library(RASCIL).Simulated observations were then performed with RASCIL based on a full-scale SKA1-LOW configuration.The performance of the BDA was systematically investigated and evaluated based on the simulated data.The experimental results confirmed that the amount of visibility data is reduced by about 50%to 85%for different time intervals(Δt_(max)).In addition,differentΔt_(max)have a significant effect on the imaging quality.The smallerΔt_(max)is,the smaller the degradation of imaging quality.

Enhanced remote astronomical archive system based on the file-level Unlimited Sliding-Window technique

Data archiving is one of the most critical issues for modern astronomical observations.With the development of a new generation of radio telescopes,the transfer and archiving of massive remote data have become urgent problems to be solved.Herein,we present a practical and robust file-level flow-control approach,called the Unlimited Sliding-Window(USW),by referring to the classic flow-control method in the TCP protocol.Based on the USW and the Next Generation Archive System(NGAS)developed for the Murchison Widefield Array telescope,we further implemented an enhanced archive system(ENGAS)using ZeroMQ middleware.The ENGAS substantially improves the transfer performance and ensures the integrity of transferred files.In the tests,the ENGAS is approximately three to twelve times faster than the NGAS and can fully utilize the bandwidth of network links.Thus,for archiving radio observation data,the ENGAS reduces the communication time,improves the bandwidth utilization,and solves the remote synchronous archiving of data from observatories such as Mingantu spectral radioheliograph.It also provides a better reference for the future construction of the Square Kilometer Array(SKA)Science Regional Center.

In-Line Chromatic Dispersion Measurement for NRZ and RZ Signals Using a Novel RF Spectrum Phase Detection Technique

In this paper, a novel method of in-line chromatic dispersion (CD) measurement is proposed, we theoretically and experimentally demonstrated the CD measurement of 10-Gbit/s NRZ and RZ signals by a novel RF spectrum phase detection technique, this is performed using in-band tone monitoring RF, electrically down-converted to direct current (DC) or a low intermediate-frequency (IF) of less than 1MHz through electronic mixing with local oscillator (LO) of 2.4 GHz. The measurement provides a large CD measuring range with good accuracies (±2000 ± 35 ps/nm), and independent of the bit-rate and data format. In addition, the use of electronic mixer and low-speed detectors makes it cost effective for in-line CD measurement.

绿色经济驱动下江苏企业基于FTA的高质量进出口策略优化研究

在绿色经济高质量发展的新形势下,自由贸易协定(FTA)不仅可以有效应对国际经贸摩擦,更有利于企业进出口降本增效,深耕区域市场,对区域开放型经济的健康、可持续发展具有重要作用。论文分析了当前江苏外贸情况及进出口企业在有效利用FTA方面存在的问题,探索江苏企业高质量发展进出口贸易的路径,从FTA原产地认知、优惠关税认知、企业核心竞争力等多角度提出并优化了进出口策略,以助力江苏企业提高进出口竞争力,从而推动江苏绿色经济效率的提升。

奥地利科研促进署发展经验及启示

奥地利联邦政府在推动产学研合作创新方面做了大量探索,并成功建设了科研促进署,有效推动了本国及各类国际计划的合作。文章在深入分析奥地利科研促进署的组织管理体系、创新支持举措的基础上,总结其治理机制和建设经验,以期对我国建设政府创新管理机构提供启示及借鉴。

Weakened humoral and cellular immune response to the inactivated COVID-19 vaccines in Chinese individuals with obesity/overweight

Inactivated COVID-19 vaccines have been widely used to vaccinate the Chinese population.However,limited literature exists to explore the effect of obesity on the humoral and cellular immune response to these vaccines.In this study,132 high BMI(Body mass index)(obesity and overweight,BMI≥24 kg/m^(2))and 82 normal BMI(BMI<24 kg/m^(2))participants were enrolled.Adverse events(AEs),Spike receptor-binding domain IgG antibody(anti-RBD-IgG),neutralizing antibodies(NAbs),and specific B-cell and T-cell responses were evaluated 21–105 days after full-course inactivated COVID-19 vaccination.The overall incidence of AEs was similar in individuals with and without obesity/overweight.No serious vaccine-related AEs occurred.Individuals with obesity/overweight had a reduced seropositivity rate of NAbs compared to those with normal BMI.Anti-RBD-IgG and NAbs titers in the high BMI group were significantly lower than those in the normal BMI group.The frequencies of RBD-specific memory B cells(MBCs)and the numbers of spike-specific TNF-α+spot-forming cells(SFCs)in individuals with obesity/overweight were reduced compared with those noted in individuals without obesity/overweight.A similar trend of weakened humoral responses was also observed in individuals with central obesity.Our study results suggested that inactivated COVID-19 vaccines were safe and well tolerated but induced poor humoral and cellular immune responses in Chinese individuals with obesity/overweight.