“美国国防高级研究计划局”（DARPA）如何跨越“死亡之谷”?

“死亡之谷”是发明到产品之间的鸿沟,“美国高级研究计划局”（DARPA）在短短50多年时间里,为世界带来了互联网、GPS等技术与产品,常常成功跨越鸿沟。从产业发展角度,跨越“死亡之谷”需要物质、智力和社会等三种资本,还要跨越技术培育和转移各个关键阶段。DARPA利用其独特的政治地位、雄厚的资金和有远见的战略思想,依靠优秀项目官员、办公室主任和局长的协同合作,以及长年培育的“DARPA社区”,一次次成功跨越“死亡之谷”。近年,DARPA为缩短跨越“死亡之谷”的时间,还采取了“众包”等一系列新举措,最后总结了DARPA成功跨越“死亡之谷”的关键。     

民间舆论场域中失效的议程设置与极化的网络群体 ——基于 “江歌事件”新浪微博数据的内容分析

【目的/意义】随着网络科技的不断进步,官方主流媒体的舆论压力与日俱增,通过对2017年的热点“江歌 事件”进行分析,结合议程设置探讨其中网络群体出现的极化现象,了解其深层次内涵,对今后媒体的舆论引导提 供借鉴意义。【方法/过程】利用微博数据进行内容分析,并结合本文分析的方法以及舆论环境和相关的理论对整个 事件发展进行剖析。【结果/结论】可以得出,媒介议程对受众议程存在较大影响并呈反相关系,议题驱动和较低的 导向需求是议程失效的原因,单一属性的议程会将受众偏激的态度引向极化。     

The measurement of proprioceptive accuracy: A systematic literature review

Background:Proprioceptive accuracy refers to the individual’ s ability to perceive proprioceptive information,that is,the information referring to the actual state of the locomotor system,which originates from mechanoreceptors located in various parts of the locomotor system and from tactile receptors located in the skin.Proprioceptive accuracy appears to be an important aspect in the evaluation of sensorimotor functioning;however,no widely accepted standard assessment exists.In this systematic ...     

Metabolic and performance responses of male runners wearing 3 types of footwear: Nike Vaporfly 4%, Saucony Endorphin racing flats,and their own shoes

Purpose:We compared running economy(RE) and 3-km time-trial(TT) variables of runners wearing Nike Vaporfly 4%(VP4),Saucony Endorphin lightweight racing flats(FLAT),and their habitual running(OWN) footwear.Methods:Eighteen male recreational runners(age=33.5± 11.9 year(mean± SD),peak oxygen uptake(VO_{2 peak})=55.8± 4.4 mL/kg·min)attended 4 sessions approximately 7 days apart.The first session consisted of a VO_{2 peak} test to inform subsequent RE speeds set at 60%,70%,and 80% of ...     

Association of accelerometer-derived step volume and intensity with hospitalizations and mortality in older adults: A prospective cohort study

Purpose:This study aimed to examine the associations of accelerometer-derived steps volume and intensity with hospitalizations and all-cause mortality in older adults.Methods:This prospective cohort study involved 768 community-dwelling Spanish older adults(78.8±4.9 years,mean±SD;53.9% females)from the Toledo Study for Healthy Aging(2012-2017).The number of steps per day and step cadence(steps/min) were derived from a hip-mounted accelerometer worn for at least 4 days at baseline.Participants we...     

Warming-induced phenological mismatch between trees and shrubs explains high-elevation forest expansion

Despite the importance of species interaction in modulating the range shifts of plants,little is known about the responses of coexisting life forms to a warmer climate.Here,we combine long-term monitoring of cambial phenology in sympatric trees and shrubs at two treelines of the Tibetan Plateau,with a meta-analysis of ring-width series from 344 shrubs and 575 trees paired across 11 alpine treelines in the Northern Hemisphere.Under a spring warming of +1℃,xylem resumption advances by 2-4 days in ...