Investigating the impacts of urban speed limit reduction through microscopic traffic simulation

Road traffic congestion has become an everyday phenomenon in today's cities all around the world.The reason is clear:at peak hours,the road network operates at full capacity.In this way,growing traffic demand cannot be satisfied,not even with traffic-responsive signal plans.The external impacts of traffic congestion come with a serious socio-economic cost:air pollution,increased travel times and fuel consumption,stress,as well as higher risk of accidents.To tackle these problems,a number of European cities have implemented reduced speed limit measures.Similarly,a general urban speed limit measure is in preparatory phase in Budapest,Hungary.In this context,a complex preliminary impact assessment is needed using a simulated environment.Two typical network parts of Budapest were analyzed with microscopic traffic simulations.The results revealed that speed limits can affect traffic differently in diverse network types indicating that thorough examination and preparation works are needed prior to the introduction of speed limit reduction.

Intracortical screw insertion plus limited open reduction in treating type 31A3 irreducible intertrochanteric fractures in the elderly

BACKGROUND In most elderly patients with intertrochanteric fractures,satisfactory fracture reduction can be achieved by closed reduction using a traction table.However,intertrochanteric fractures cannot achieve satisfactory reduction in a few patients,which is called irreducible intertrochanteric fractures.Especially for type 31A3 irreducible intertrochanteric fractures,limited open reduction of the broken end with different intraoperative reduction methods is required to achieve satisfactory reduction and fixation.AIM To discuss clinical efficacy of intracortical screw insertion plus limited open reduction in type 31A3 irreducible intertrochanteric fractures in the elderly.METHODS A retrospective analysis was performed on 23 elderly patients with type 31A3 irreducible intertrochanteric fractures(12 males and 11 females,aged 65-89-yearsold)who received treatment at the orthopedics department.After type 31A3 irreducible intertrochanteric fractures were confirmed by intraoperative C-arm,all of these cases received intracortical screw insertion plus limited open reduction in the broken end with intramedullary screw internal fixation.The basic information of surgery,reduction effects,and functional recovery scores of the hip joint were assessed.RESULTS All patients were followed up for 13.8 mo on average.The operation time was 53.8±13.6 min(40-95 min).The intraoperative blood loss was 218.5±28.6 mL(170-320 mL).The average number of intraoperative X-rays was 22.8±4.6(18-33).The average time to fracture union was 4.8±0.7 mo.The reduction effect was assessed using Kim’s fracture reduction evaluation.Twenty cases achieved grade I fracture reduction and three cases grade II fracture reduction.All of them achieved excellent or good fracture reduction.Upon the last follow-up,the functional recovery scores score was 83.6±9.8,which was not significantly different from the functional recovery scores score(84.8±10.7)before the fracture(t=0.397,P=0.694).CONCLUSION With careful preoperative preparation,intracortical screw insertion plus limited open reduction contributed to high-quality fracture reduction and fixation.Good clinical outcomes were achieved without increasing operation time and intraoperative blood loss.

试论运动训练科学研究的方法论问题

运动训练科学的方法论是运动训练科学理论研究的一个重要内容和手段。目前,在运动训练科学研究邻域存在着两种方法论模式,即整体论与还原论,这两种方法论模式有力地推动运动训练科学研究的发展。然而,运动训练是复杂性系统,这两种简单性方法模式在解决复杂的运动训练问题时都存在着各自的局限性。复杂性系统科学研究成果为运动训练科学研究方法论创新提供可能。复杂性方法论是未来运动训练科学研究的方法论发展方向。

Enhanced zinc storage performance of mixed valent manganese oxide for flexible coaxial fiber zinc-ion battery by limited reduction control

While manganese-based cathodes have been intensively studied for zinc-ion batteries(ZIBs),the limited rate capability and cycle life have always been a difficult problem to be solved.Here,we report a mixed valent manganese oxide(MnOx)cathode with superior electrochemical performance,which exhibits a high specific capacity of 450 mA h/g at 0.2 C and a satisfactory specific capacity of 158.3 mA h/g at a high rate of 5 C.The mixed cathode system reduces the charge transfer resistance,and show good surface stability and adsorption properties,so it is beneficial for the storage of Zn^(2+).Meanwhile,coaxial fiber ZIBs(CFZIBs)with splendid flexibility are assembled utilizing the elaborately prepared cathode material.The CFZIBs achieve a reversible capacity of 255.8 m A h/g and the capacity retention rate is as high as 80%after 1000 bending deformations.This study provides new opportunities for designing ZIBs with high performance and high flexibility.

因果操纵非还原论及其问题

根据伍德沃德的因果操纵非还原论,因果结构模型被解释为机制,这种思路可以解决因果解释的模糊性问题以及传统因果操纵还原论面临的循环和人类中心主义问题。当然,伍德沃德的这种因果操纵非还原论也面临着干预的单一标准和干预的模态特征问题,从解释因果概念和陈述因果主张的真值条件的视角看,因果操纵非还原论事实上提供了一个不充分的因果关系理论。