简介：Densegas-particleflowsareencounteredinavarietyofindustriallyimportantprocessesforlargescaleproductionoffuels,fertilizersandbasechemicals.Thescale-upoftheseprocessesisoftenproblematicandisrelatedtotheintrinsiccomplexitiesoftheseflowswhichareunfortunatelynotyetfullyunderstooddespitesignificanteffortsmadeinbothacademicandindustrialresearchlaboratories.Indensegas-particleflowsboth(effective)fluid-particleand(dissipative)particle-particleinteractionsneedtobeaccountedforbecausethesephenomenatoalargeextentgoverntheprevailingflowphenomena,i.e.theformationandevolutionofheterogeneousstructures.Thesestructureshavesignificantimpactonthequalityofthegas-solidcontactandasadirectconsequencethereofstronglyaffecttheperformanceoftheprocess.Duetotheinherentcomplexityofdensegas-particlesflows,wehaveadoptedamulti-scalemodelingapproachinwhichbothfluid-particleandparticle-particleinteractionscanbeproperlyaccountedfor.Theideaisessentiallythatfundamentalmodels,takingintoaccounttherelevantdetailsoffluid-particle(latticeBoltzmannmodel)andparticle-particle(discreteparticlemodel)interactions,areusedtodevelopclosurelawstofeedcontinuummodelswhichcanbeusedtocomputetheflowstructuresonamuchlarger(industrial)scale.Ourmulti-scaleapproach(seeFig.1)involvesthelatticeBoltzmannmodel,thediscreteparticlemodel,thecontinuummodelbasedonthekinetictheoryofgranularflowandthediscretebubblemodel.Inthispaperwegiveanoverviewofthemulti-scalemodelingstrategy,accompaniedbyillustrativecomputationalresultsforbubbleformation.Inaddition,areaswhichneedsubstantialfurtherattentionwillbehighlighted.

简介：AbstractSpondyloptosis in the clinic is rarely reported. We herein present a 47-year-old female, who suffered from a crush injury directly by a heavy cylindrical object from the lateral side. She was diagnosed to have traumatic L3 spondyloptosis with multiple traumas. Staged surgical procedures were conducted and a three-year follow-up was obtained. Eventually, normal spinal alignment was restored, and neurological deficits were gradually improved. At three years follow-up, the motor strength scores and function of the sphincters were incompletely improved. Previously published reports on traumatic lumbar spondyloptosis were reviewed and several critical points for management of this severe type of spinal injury were proposed. First, thoracolumbar and lumbosacral junction were mostly predilection sites. Second, numerous patients involving traumatic lumbar spondyloptosis were achieved to American Spinal Injury Association grade A. Third, lumbar spondyloptosis was commonly coupling with cauda equina injury. Finally, the outcomes were still with poorly prognosis and recovery of patients was correlation to spondyloptosis severity. Based on this case report and literatures review, we highlighted that the spinal alignment restoration relying on staged operations and following rehabilitation hereof are both important once facing with multiple traumas. Furthermore, we suggested to perform routine CT angiography during lumbar spondyloptosis to justify whether there are large vessel compression or injury.

简介：AbstractBackground:Nucleic acid test (NAT) could effectively control the spread of COVID-19 caused by large-scale sports competitions. However, quantitative analysis on the appropriate frequency of NAT is scarce, and the cost-effectiveness and necessity of high-frequency NAT remain to be fully explored and validated. This study aims to optimize the COVID-19 surveillance strategies through cost-effectiveness analysis for the Tokyo 2020 Olympic Games and the upcoming Beijing 2022 Olympic Winter Games.Methods:A total of 18 scenarios were designed regarding the NAT frequency, symptom monitoring, and strengthening close-contact control. An agent-based stochastic dynamic model was used to compare the cost-effectiveness of different NAT scenarios and optimize the surveillance strategies. The dynamics of the proposed model included the arrival and departure of agents, transmission of the disease according to Poisson processes, and quarantine of agents based on regular NATs and symptom onset. Accumulative infections, cost, and incremental cost-effectiveness ratio (ICER) were simulated in the frame of the model. ICER was used to compare the cost-effectiveness of different scenarios. Univariate sensitivity analysis was performed to test the robustness of the results.Results:In Scenario 16, where the competition-related personnel (CRP) received NAT daily and national sports delegation (NSD) with quarantined infections accepted an additional NAT daily, accumulative infection was 320.90 (90 initial infections), the total cost was (United States Dollar) USD 8 920 000, and the cost of detecting out each infection was USD 27 800. Scenario 16 would reduce the total cost by USD 22 570 000 (avoid 569.61 infections), USD 1 420 000 (avoid 47.2 infections) compared with Scenario 10 (weekly NAT, strengthened close contact control) and Scenario 7 (daily NAT, no strengthened close contact control), respectively. Sensitivity analysis showed that the result was most sensitive to the change in basic reproductive number.Conclusions:High-frequency NATs such as bidaily, daily, and twice a day were cost-effective. NAT daily for CRP with strengthening close-contact control could be prioritized in defense against COVID-19 at large-scale sports competitions. This study could assist policymakers by assessing the cost-effectiveness of NAT scenarios and provide the host country with an optimal COVID-19 surveillance strategy.

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简介：训练策略的一条河的选择为更低的黄河(LYR)是极其重要的。当前，宽河的训练策略在训练LYR适用。然而，在在黄河盆的水文学过程的显著变化，以及从在黄河盆的社会经济的开发的立即的压力，使如果有可能性改变从到狭窄河的训练的宽河的训练训练策略的河，考虑必要。这研究调查通过数字模拟在LYR上训练策略的不同的河的影响。一一个维(1-D)模型被用来为未来模仿河的过程50年并且一三维(3-D)模型被使用学习典型洪水。学习集中了于河形态学，结果看那在两水分泌物的在场减少趋势和沉积负担是否坚持，在LYR的免职率将进一步减少不管什么策略被使用。特别，狭窄河的训练能达到目的与宽河的训练相比在LYR增加沉积运输能力。如果到来的水和沉积负担恢复到最后世纪的吝啬的水平，主要隧道收缩不管多么不可避免地由于沉积发生为宽河、狭窄河训练。最重要地，这研究证明狭窄河的训练在整个LYR上减少免职数量，但是它几乎不在减轻推迟的河的发展提供很少帮助。相反，狭窄河的训练能在河模式从高度漫步到蜿蜒地流变化的过渡活动范围引起沉积，进一步的变得更坏在那里的驼峰免职。因为关于在在可行工程的黄河盆，和缺乏的水文学过程的未来变化的无常，测量在LYR减轻推迟的河和驼峰免职问题，小心应该在为LYR训练策略的河里关于变化被行使。

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简介：Femtocell是一种有希望的技术与低力量、费用有益的小基础车站改进网络性能。然而，在femtocell网络的干扰有限现实使干扰和资源管理成为钥匙到完成femtocell网络的好处。在这份报纸，下列贡献一步一步地被做：首先，根据在技术和第三产生合伙的网络建筑学投射的认知无线电(CR)(3GPP)的干扰温度模型(ITM)，长期的进化进展了(LTE--一)，优化再使用femtocell的子通道的能力的问题模型在划分策略的频率下面被建立，联合考虑平均干扰限制和即时干扰限制。第二，利用凸的理论，再使用femtocell的子通道的最佳的力量分配被导出。第三在使隧道褪色的瑞利下面，子通道的靠近形式的表情可重用的概率和能力被导出。最后，数字结果被进行到证实我们的分析结果，它能为femtocell网络推广的频率资源分配提供理论指导。

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简介：Basedonthesystemtheory,thispaperdiscussesthestructureandefficiencyofagriculturallanduseinKaifengSuburban.Suchpresentproblemsasbenefitdeviationfromresourceallocation,distinguishedunemploymentandfourkindsofcontributionofurbanagriculturelandusearerevealed.Then,intheviewofsustainabledevelopment,someresolutionmeasurestotheproblemsareadvancedout.Thesesuggestionsincludefarmlandprotection,ecologicalagriculture,sustainablelanduseandinputdecreaseofsyntheticmatter.

简介：这份报纸为在全球规模从计量器观察，卫星估计(SE)，和数字预言合并每日的降水信息描述策略。策略被设计把全身的偏爱和随机的错误从每单个每日的降水来源移开生产通过三的全球每日的降水产品走的更好的gridded。首先，匹配过程的累积分发功能被执行在定位计量器的陆地区域上移开全身的偏爱。然后，在在海洋区域上的SE和模型预言(MP)的全面偏爱基于每月的降水用重新可伸缩的策略被改正。第三，最佳的插值(OI)基于合并计划(作为HL-OI计划参考了)被用来联合从每来源减少随机的错误并且生产一个gaugesatellite模型的不偏的计量器观察，SE，和MP合并每日的降水分析，叫的BMEP-d(北京气候中心把降水的评价与每日的分辨率合并了)，与完全的全球范围。从一个四年的时期(2011-14)的BMEP-d数据表明合并策略的能力提供实质地改进的质量的全球每日的降水。为量的错误得益于HL-OI计划的优点估计，更好的来源数据能在合并进程期间获得更多的重量。BMEP-d数据展览有在中间、低的纬度的卫星和计量器来源数据，并且与在高纬度的模型来源数据的更高的一致性。总的来说，对GPCP-1DD(GPCP一个度日报)的独立确认证明在BMEP-d和GPCP-1DD之间的一致性以空间模式，时间的可变性，概率分发，和统计降水事件比每来源数据集的那些高。

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简介：AbstractBackground:Dengue is the fastest spreading arboviral disease, posing great challenges on global public health. A reproduceable and comparable global genotyping framework for contextualizing spatiotemporal epidemiological data of dengue virus (DENV) is essential for research studies and collaborative surveillance.Methods:Targeting DENV-1 spreading prominently in recent decades, by reconciling all qualified complete E gene sequences of 5003 DENV-1 strains with epidemiological information from 78 epidemic countries/areas ranging from 1944 to 2018, we established and characterized a unified global high-resolution genotyping framework using phylogenetics, population genetics, phylogeography, and phylodynamics.Results:The defined framework was discriminated with three hierarchical layers of genotype, subgenotype and clade with respective mean pairwise distances 2-6%, 0.8-2%, and ≤ 0.8%. The global epidemic patterns of DENV-1 showed strong geographic constraints representing stratified spatial-genetic epidemic pairs of Continent-Genotype, Region-Subgenotype and Nation-Clade, thereby identifying 12 epidemic regions which prospectively facilitates the region-based coordination. The increasing cross-transmission trends were also demonstrated. The traditional endemic countries such as Thailand, Vietnam and Indonesia displayed as persisting dominant source centers, while the emerging epidemic countries such as China, Australia, and the USA, where dengue outbreaks were frequently triggered by importation, showed a growing trend of DENV-1 diffusion. The probably hidden epidemics were found especially in Africa and India. Then, our framework can be utilized in an accurate stratified coordinated surveillance based on the defined viral population compositions. Thereby it is prospectively valuable for further hampering the ongoing transition process of epidemic to endemic, addressing the issue of inadequate monitoring, and warning us to be concerned about the cross-national, cross-regional, and cross-continental diffusions of dengue, which can potentially trigger large epidemics.Conclusions:The framework and its utilization in quantitatively assessing DENV-1 epidemics has laid a foundation and re-unveiled the urgency for establishing a stratified coordinated surveillance platform for blocking global spreading of dengue. This framework is also expected to bridge classical DENV-1 genotyping with genomic epidemiology and risk modeling. We will promote it to the public and update it periodically.

简介：AbstractBackground:Reduced application of percutaneous coronary intervention (PCI) is associated with higher mortality rates after ST-segment elevation myocardial infarction (STEMI). We aimed to evaluate potential factors contributing to the refusal of PCI in STEMI patients in China.Methods:We studied 957 patients diagnosed with STEMI in the emergency departments (EDs) of six public hospitals in China. The differences in baseline characteristics and 30-day outcome were investigated between patients who refused PCI and those who underwent PCI. Multivariable logistic regression was used to evaluate the potential factors associated with refusing PCI.Results:The potential factors contributing to refusing PCI were older than 65 years (odds ratio [OR] 2.66, 95% confidence interval [CI] 1.56-4.52, P < 0.001), low body mass index (BMI) (OR 0.91, 95% CI 0.84-0.98, P = 0.013), not being married (OR 0.29, 95% CI 0.17-0.49, P < 0.001), history of myocardial infarction (MI) (OR 2.59, 95% CI 1.33-5.04, P = 0.005), higher heart rate (HR) (OR 1.02, 95% CI 1.01-1.03, P = 0.002), cardiac shock in the ED (OR 5.03, 95% CI 1.48-17.08, P = 0.010), pre-hospital delay (>12 h) (OR 3.31, 95% CI 1.83-6.02, P < 0.001) and not being hospitalized in a tertiary hospital (OR 0.45, 95% CI 0.27-0.75, P = 0.002). Compared to men, women were older, were less often married, had a lower BMI and were less often hospitalized in tertiary hospitals.Conclusions:Patients who were older, had lower economic or social status, and had poorer health status were more likely to refuse PCI after STEMI. There was a sex difference in the potential predictors of refusing PCI. Targeted efforts should be made to improve the acceptance of PCI among patients with STEMI in China.

简介：Accordingtoperformanceanalysisofathree-phasegrid-connectedinvertermathematicalmodelofadirectly-drivenwindturbinewithapermanentmagnetsynchronousgenerator(D-PMSG)underunbalancednetworkvoltageconditions,adualcurrent-loopcontrolstrategy(DCC)orientedonpositivevoltageandnegativecurrentisproposedtoinhibittheDCvoltagefluctuation.Meanwhile,anotchfilterisintroducedintotheconventionalcontrolstrategyofaphase-lockedlooptocompletethelowvoltageridethrough(LVRT)abilityofthewindgenerator.A1.5-MWD-PMSGwithaback-to-backIGBTfrequencyconverterwassimulatedinthePSCAD/EMTDCenvironment,andsimulationresultsshowedthat:themaximumwindpowertrackingwasachievedinthissystemandtheproposedDCCstrategycouldsuccessfullyinhibittherisingagingofDCvoltageandenhancetheride-throughcapabilityofD-PMSGwindgenerationsystemunderunbalancednetworkvoltageconditions.

简介：基于自动电压，控制(AVC)和电池精力存储控制的改进自动电压协作控制策略(AVCCS)(BESC)被建议让光电的连接格子的系统(PVGS)减轻环境骚乱引起的电压变化。当小环境骚乱发生时，仅仅AVC被使用，当BESC与当大骚乱发生时，制止电压变化的AVC被合并时。决定电压变化的允许的振幅的一个可调节的参数被介绍认识到上述切换的进程。一个基准低电压分发系统包括PVGS被使用商业软件建立挖沉默。模拟结果证明在AVCCS下面的电压满足IEEE标准1547，并且安装电池电容是也减少了。同时，电池服务生活被在控制过程避免经常的控告/解除扩大。

简介：为了解决在控制设备存在的不同时间延期，在空间结构上安装了，在这研究，用2N的分离分析精确算法被选择基于基于市场的控制(MBC)为长跨度的结构解决multi-time-delay问题方法。间隔的概念混合了精力从计算结构的力学和最佳的控制研究区域被介绍，并且它把MBCmulti-time-delay控制器的设计翻译成片断矩阵的一个解决方案。这条途径在空间及时转变连续算法到并行计算，极大地改进解决的效率和数字稳定性。设计控制器能与线性控制力量联合考虑时间延期的问题并且为大时间延期条件是特别有效的。长跨度的结构的一个数字例子被选择表明介绍控制器的有效性，并且时间延期被发现在结果上有重要影响。

简介：Recentadvancesinstemcelltechnologieshaveopenednewavenuesforthetreatmentofanumberofdiseasesstilllackingeffectivetherapeuticoptions.Celltransplantationhasemergedasamongthemostpromisingclinicalinterventionfordisorderssuchasinjuries,diabetes,liver