To take an indirect route(detour)in order to reach a specific target requires complex cognitive processes.Yet more demanding,from the cognitive point of view,is when the goal is only visible at the beginning of the de...To take an indirect route(detour)in order to reach a specific target requires complex cognitive processes.Yet more demanding,from the cognitive point of view,is when the goal is only visible at the beginning of the detour.In spiders from the family Sa lticidae,vision is a key sensory modal-ity mediating navigation and prey search.Their acute vision allows them to perform complicated detours,possibly as a consequence of the multitude of potential routes in their typically complex 3-dimensional habitats.We used a 4-route choice test,in which routes differed in being either short or long and in the presence or absence of a lure of a prey item,to investigate route assessment in 2 salticid species,Trite planiceps and Marpissa marina.Although both species showed evidence of motivation to follow lured-routes,judging by the number of times they re-oriented toward them while detouring,we found that Trite chose short routes in preference to long routes,but did not prefer the lured-routes.In contrast,Marpissa exhibited random route choice,although it ori-ented toward lured-routes more often than control routes(lure absent).Our results suggest that decision-making processes about which route to take occurs before embarking on a route,but this is cognitively challenging.Spiders exhibited cognitive limitations in which the lack of visibility of the goal affected success.However,the severity of cognitive limitations depended on species.We suggest that variability in spatial ability across the Salticidae may be related to the habitat complexity inhabited by each species.展开更多
Long-distance migratory birds often face major geographical barriers on their journey.While some species are able to cross them,others use longer routes to avoid such barriers.Little is known about the strategies of S...Long-distance migratory birds often face major geographical barriers on their journey.While some species are able to cross them,others use longer routes to avoid such barriers.Little is known about the strategies of Siberian landbird migrants,which either cross or circumvent the deserts and mountain ranges of Central Asia en route to their non-breeding sites in Southeast Asia.Here we compare data on migration phenology and morphology from two bird ringing stations in eastern Russia,situated at similar latitudes but with a longitudinal difference of 1500 km,to hypothesise migration patterns.We found significant differences in timing between the two sites(birds migrated significantly earlier in spring and significantly later in autumn in the east),suggesting longitudinal migration as a result of migration detour.However,morphological differences show a less clear pattern.We argue that most Siberian landbirds might opt for a detour through the Russian Far East instead of a direct route in order to avoid unfavourable stop-over habitat in Central Asia.However,tracking studies will be necessary to prove this.展开更多
Axonal regeneration and ifber regrowth is limited in the adult central nervous system, but re-search over the last decades has revealed a high intrinsic capacity of brain and spinal cord circuits to adapt and reorgani...Axonal regeneration and ifber regrowth is limited in the adult central nervous system, but re-search over the last decades has revealed a high intrinsic capacity of brain and spinal cord circuits to adapt and reorganize after smaller injuries or denervation. Short-distance ifber growth and synaptic rewiring was found in cortex, brain stem and spinal cord and could be associated with restoration of sensorimotor functions that were impaired by the injury. Such processes of struc-tural plasticity were initially observed in the corticospinal system following spinal cord injury or stroke, but recent studies showed an equally high potential for structural and functional reorganization in reticulospinal, rubrospinal or propriospinal projections. Here we review the lesion-induced plastic changes in the propriospinal pathways, and we argue that they represent a key mechanism triggering sensorimotor recovery upon incomplete spinal cord injury. The for-mation or strengthening of spinal detour pathways bypassing supraspinal commands around the lesion site to the denervated spinal cord were identiifed as prominent neural substrate inducing substantial motor recovery in different species from mice to primates. Indications for the exis-tence of propriospinal bypasses were also found in humans after cortical stroke. It is mandatory for current research to dissect the biological mechanisms underlying spinal circuit remodeling and to investigate how these processes can be stimulated in an optimal way by therapeutic inter-ventions (e.g., ifber-growth enhancing interventions, rehabilitation). This knowledge will clear the way for the development of novel strategies targeting the remarkable plastic potential of pro-priospinal circuits to maximize functional recovery after spinal cord injury.展开更多
Direct X是主流图形API,在多媒体、娱乐等领域得到广泛应用。为实现图形表面的跨进程共享,从Direct X 10开始使用Direct X图形基础架构(DXGI)对图形硬件进行底层管理。DXGI带来性能提升的同时也给图形应用程序的截获工作带来困难。为完...Direct X是主流图形API,在多媒体、娱乐等领域得到广泛应用。为实现图形表面的跨进程共享,从Direct X 10开始使用Direct X图形基础架构(DXGI)对图形硬件进行底层管理。DXGI带来性能提升的同时也给图形应用程序的截获工作带来困难。为完成Direct X 10程序的拦截,需要同时截获多个图形库的函数。针对此问题,完善DLL替换+Detours的图形应用程序截获框架,克服现有截获技术的缺陷,完成Direct X 10程序的截获工作,并解决因DXGI、D3D10图形库间依赖关系产生的进程死锁问题。最后,基于该截获框架,开发出一套单机驱动的多投影显示系统,Direct X 10程序不需做任何修改就能多投影显示。实验结果表明,使用所提出的截获技术后图形应用程序画面流畅,运行稳定。展开更多
Spinal cord injury is a devastating condition that is followed by long and often unsuccessful recovery after trauma. The state of the art approach to manage paralysis and concomitant impairments is rehabilitation, whi...Spinal cord injury is a devastating condition that is followed by long and often unsuccessful recovery after trauma. The state of the art approach to manage paralysis and concomitant impairments is rehabilitation, which is the only strategy that has proven to be effective and beneficial for the patients over the last decades. How rehabilitation influences the remodeling of spinal axonal connections in patients is important to understand, in order to better target these changes and define the optimal timing and onset of training. While clinically the answers to these questions remain difficult to obtain, rodent models of rehabilitation like bicycling, treadmill training, swimming, enriched environments or wheel running that mimic clinical rehabilitation can be helpful to reveal the axonal changes underlying motor recovery. This review will focus on the different animal models of spinal cord injury rehabilitation and the underlying changes in neuronal networks that are improved by exercise and rehabilitation.展开更多
To deal with the dynamic and imbalanced traffic requirements in Low Earth Orbit satellite networks, several distributed load balancing routing schemes have been proposed. However, because of the lack of global view, t...To deal with the dynamic and imbalanced traffic requirements in Low Earth Orbit satellite networks, several distributed load balancing routing schemes have been proposed. However, because of the lack of global view, these schemes may lead to cascading congestion in regions with high volume of traffic. To solve this problem, a Hybrid-Traffic-Detour based Load Balancing Routing(HLBR) scheme is proposed, where a Long-Distance Traffic Detour(LTD) method is devised and coordinates with distributed traffic detour method to perform self-adaptive load balancing. The forwarding path of LTD is acquired by the Circuitous Multipath Calculation(CMC) based on prior geographical information, and activated by the LTDShift-Trigger(LST) through real-time congestion perception. Simulation results show that the HLBR can mitigate cascading congestion and achieve efficient traffic distribution.展开更多
This study evaluates the Dynamic Message Signs (DMSs) use to dissipate incident information on the freeways in Las Vegas, Nevada. It focuses on the DMSs message timing, extent, and content, from the operators’ and dr...This study evaluates the Dynamic Message Signs (DMSs) use to dissipate incident information on the freeways in Las Vegas, Nevada. It focuses on the DMSs message timing, extent, and content, from the operators’ and drivers’ perspectives, considering the variability in drivers’ freeway experience. Two-week incidents data with fifty-nine incidents, DMS log data, and responses from a survey questionnaire were used. The descriptive analysis of the incidents revealed that about 54% of the incidents had their information posted on the DMSs;however, information of only 18.6% of the incidents was posted on time. The posted information covered the incident type (54.2%), location (49.2%), and lane blockage (45.8%), while the expected delay or the time the incident has lasted are rarely posted. Further, the standard DMSs are the most preferred sources of traffic information on the freeway compared to the travel time only DMSs, and the graphical map boards. The logistic regression applied to the survey responses revealed that regular freeway users are less likely to take an alternative route when they run into congestion, given no other </span><span style="font-family:Verdana;">information is available. Conversely, when given accurate information</span><span style="font-family:Verdana;"> through DMSs, regular freeway users are about 2.9 times more likely to detour. Furthermore, regular freeway users perceive that the DMSs show clear information about the incident location. Upon improving the DMSs usage, 73% of respondents suggested that the information be provided earlier, and 54% requested improvements on congestion duration and length information. These findings can be used by the DMSs operators in Nevada and worldwide to improve freeway operations.展开更多
文摘To take an indirect route(detour)in order to reach a specific target requires complex cognitive processes.Yet more demanding,from the cognitive point of view,is when the goal is only visible at the beginning of the detour.In spiders from the family Sa lticidae,vision is a key sensory modal-ity mediating navigation and prey search.Their acute vision allows them to perform complicated detours,possibly as a consequence of the multitude of potential routes in their typically complex 3-dimensional habitats.We used a 4-route choice test,in which routes differed in being either short or long and in the presence or absence of a lure of a prey item,to investigate route assessment in 2 salticid species,Trite planiceps and Marpissa marina.Although both species showed evidence of motivation to follow lured-routes,judging by the number of times they re-oriented toward them while detouring,we found that Trite chose short routes in preference to long routes,but did not prefer the lured-routes.In contrast,Marpissa exhibited random route choice,although it ori-ented toward lured-routes more often than control routes(lure absent).Our results suggest that decision-making processes about which route to take occurs before embarking on a route,but this is cognitively challenging.Spiders exhibited cognitive limitations in which the lack of visibility of the goal affected success.However,the severity of cognitive limitations depended on species.We suggest that variability in spatial ability across the Salticidae may be related to the habitat complexity inhabited by each species.
基金Funding supply on Baikal Bird Ringing Station was conducted by Baikalsky State Nature Reserve。
文摘Long-distance migratory birds often face major geographical barriers on their journey.While some species are able to cross them,others use longer routes to avoid such barriers.Little is known about the strategies of Siberian landbird migrants,which either cross or circumvent the deserts and mountain ranges of Central Asia en route to their non-breeding sites in Southeast Asia.Here we compare data on migration phenology and morphology from two bird ringing stations in eastern Russia,situated at similar latitudes but with a longitudinal difference of 1500 km,to hypothesise migration patterns.We found significant differences in timing between the two sites(birds migrated significantly earlier in spring and significantly later in autumn in the east),suggesting longitudinal migration as a result of migration detour.However,morphological differences show a less clear pattern.We argue that most Siberian landbirds might opt for a detour through the Russian Far East instead of a direct route in order to avoid unfavourable stop-over habitat in Central Asia.However,tracking studies will be necessary to prove this.
文摘Axonal regeneration and ifber regrowth is limited in the adult central nervous system, but re-search over the last decades has revealed a high intrinsic capacity of brain and spinal cord circuits to adapt and reorganize after smaller injuries or denervation. Short-distance ifber growth and synaptic rewiring was found in cortex, brain stem and spinal cord and could be associated with restoration of sensorimotor functions that were impaired by the injury. Such processes of struc-tural plasticity were initially observed in the corticospinal system following spinal cord injury or stroke, but recent studies showed an equally high potential for structural and functional reorganization in reticulospinal, rubrospinal or propriospinal projections. Here we review the lesion-induced plastic changes in the propriospinal pathways, and we argue that they represent a key mechanism triggering sensorimotor recovery upon incomplete spinal cord injury. The for-mation or strengthening of spinal detour pathways bypassing supraspinal commands around the lesion site to the denervated spinal cord were identiifed as prominent neural substrate inducing substantial motor recovery in different species from mice to primates. Indications for the exis-tence of propriospinal bypasses were also found in humans after cortical stroke. It is mandatory for current research to dissect the biological mechanisms underlying spinal circuit remodeling and to investigate how these processes can be stimulated in an optimal way by therapeutic inter-ventions (e.g., ifber-growth enhancing interventions, rehabilitation). This knowledge will clear the way for the development of novel strategies targeting the remarkable plastic potential of pro-priospinal circuits to maximize functional recovery after spinal cord injury.
文摘Direct X是主流图形API,在多媒体、娱乐等领域得到广泛应用。为实现图形表面的跨进程共享,从Direct X 10开始使用Direct X图形基础架构(DXGI)对图形硬件进行底层管理。DXGI带来性能提升的同时也给图形应用程序的截获工作带来困难。为完成Direct X 10程序的拦截,需要同时截获多个图形库的函数。针对此问题,完善DLL替换+Detours的图形应用程序截获框架,克服现有截获技术的缺陷,完成Direct X 10程序的截获工作,并解决因DXGI、D3D10图形库间依赖关系产生的进程死锁问题。最后,基于该截获框架,开发出一套单机驱动的多投影显示系统,Direct X 10程序不需做任何修改就能多投影显示。实验结果表明,使用所提出的截获技术后图形应用程序画面流畅,运行稳定。
基金Work in FMB laboratory is supported by grants from the Deutsche Forschungsgemeinschaft(DFG,SFB870)by the Munich Center for Neurosciences(MCN)+2 种基金the Wings for Life foundationsupported by the Munich Center for Systems Neurology(DFG,SyNergyEXC 1010)
文摘Spinal cord injury is a devastating condition that is followed by long and often unsuccessful recovery after trauma. The state of the art approach to manage paralysis and concomitant impairments is rehabilitation, which is the only strategy that has proven to be effective and beneficial for the patients over the last decades. How rehabilitation influences the remodeling of spinal axonal connections in patients is important to understand, in order to better target these changes and define the optimal timing and onset of training. While clinically the answers to these questions remain difficult to obtain, rodent models of rehabilitation like bicycling, treadmill training, swimming, enriched environments or wheel running that mimic clinical rehabilitation can be helpful to reveal the axonal changes underlying motor recovery. This review will focus on the different animal models of spinal cord injury rehabilitation and the underlying changes in neuronal networks that are improved by exercise and rehabilitation.
基金supported by the National Science Foundation of China(No.61472189)Zhejiang Provincial Natural Science Foundation of China(No.LY18F030015)Wenzhou Public Welfare Science and Technology Project of China(No.G20150015)
文摘To deal with the dynamic and imbalanced traffic requirements in Low Earth Orbit satellite networks, several distributed load balancing routing schemes have been proposed. However, because of the lack of global view, these schemes may lead to cascading congestion in regions with high volume of traffic. To solve this problem, a Hybrid-Traffic-Detour based Load Balancing Routing(HLBR) scheme is proposed, where a Long-Distance Traffic Detour(LTD) method is devised and coordinates with distributed traffic detour method to perform self-adaptive load balancing. The forwarding path of LTD is acquired by the Circuitous Multipath Calculation(CMC) based on prior geographical information, and activated by the LTDShift-Trigger(LST) through real-time congestion perception. Simulation results show that the HLBR can mitigate cascading congestion and achieve efficient traffic distribution.
文摘This study evaluates the Dynamic Message Signs (DMSs) use to dissipate incident information on the freeways in Las Vegas, Nevada. It focuses on the DMSs message timing, extent, and content, from the operators’ and drivers’ perspectives, considering the variability in drivers’ freeway experience. Two-week incidents data with fifty-nine incidents, DMS log data, and responses from a survey questionnaire were used. The descriptive analysis of the incidents revealed that about 54% of the incidents had their information posted on the DMSs;however, information of only 18.6% of the incidents was posted on time. The posted information covered the incident type (54.2%), location (49.2%), and lane blockage (45.8%), while the expected delay or the time the incident has lasted are rarely posted. Further, the standard DMSs are the most preferred sources of traffic information on the freeway compared to the travel time only DMSs, and the graphical map boards. The logistic regression applied to the survey responses revealed that regular freeway users are less likely to take an alternative route when they run into congestion, given no other </span><span style="font-family:Verdana;">information is available. Conversely, when given accurate information</span><span style="font-family:Verdana;"> through DMSs, regular freeway users are about 2.9 times more likely to detour. Furthermore, regular freeway users perceive that the DMSs show clear information about the incident location. Upon improving the DMSs usage, 73% of respondents suggested that the information be provided earlier, and 54% requested improvements on congestion duration and length information. These findings can be used by the DMSs operators in Nevada and worldwide to improve freeway operations.