scholarly journals Temporal and spatial effects of subauroral polarization streams on the thermospheric dynamics

2012 ◽  
Vol 117 (A11) ◽  
pp. n/a-n/a ◽  
Author(s):  
Hui Wang ◽  
Hermann Lühr ◽  
Patricia Ritter ◽  
Guram Kervalishvili
Author(s):  
Rachel M. Brown ◽  
Erik Friedgen ◽  
Iring Koch

AbstractActions we perform every day generate perceivable outcomes with both spatial and temporal features. According to the ideomotor principle, we plan our actions by anticipating the outcomes, but this principle does not directly address how sequential movements are influenced by different outcomes. We examined how sequential action planning is influenced by the anticipation of temporal and spatial features of action outcomes. We further explored the influence of action sequence switching. Participants performed cued sequences of button presses that generated visual effects which were either spatially compatible or incompatible with the sequences, and the spatial effects appeared after a short or long delay. The sequence cues switched or repeated across trials, and the predictability of action sequence switches was varied across groups. The results showed a delay-anticipation effect for sequential action, whereby a shorter anticipated delay between action sequences and their outcomes speeded initiation and execution of the cued action sequences. Delay anticipation was increased by predictable action switching, but it was not strongly modified by the spatial compatibility of the action outcomes. The results extend previous demonstrations of delay anticipation to the context of sequential action. The temporal delay between actions and their outcomes appears to be retrieved for sequential planning and influences both the initiation and the execution of actions.


2021 ◽  
Vol 9 (4) ◽  
pp. 363
Author(s):  
Camilla Bertolini ◽  
Edouard Royer ◽  
Roberto Pastres

Effects of climatic changes in transitional ecosystems are often not linear, with some areas likely experiencing faster or more intense responses, which something important to consider in the perspective of climate forecasting. In this study of the Venice lagoon, time series of the past decade were used, and primary productivity was estimated from hourly oxygen data using a published model. Temporal and spatial patterns of water temperature, salinity and productivity time series were identified by applying clustering analysis. Phytoplankton and nutrient data from long-term surveys were correlated to primary productivity model outputs. pmax, the maximum oxygen production rate in a given day, was found to positively correlate with plankton variables measured in surveys. Clustering analysis showed the occurrence of summer heatwaves in 2008, 2013, 2015 and 2018 and three warm prolonged summers (2012, 2017, 2019) coincided with lower summer pmax values. Spatial effects in terms of temperature were found with segregation between confined and open areas, although the patterns varied from year to year. Production and respiration differences showed that the lagoon, despite seasonality, was overall heterotrophic, with internal water bodies having greater values of heterotrophy. Warm, dry years with high salinity had lower degrees of summer autotrophy.


Parasitology ◽  
2018 ◽  
Vol 146 (1) ◽  
pp. 50-73
Author(s):  
Jerzy M. Behnke ◽  
Anna Bajer ◽  
Jolanta Behnke-Borowczyk ◽  
Natalie Clisham ◽  
Francis Gilbert ◽  
...  

AbstractThe importance of parasites as a selective force in host evolution is a topic of current interest. However, short-term ecological studies of host–parasite systems, on which such studies are usually based, provide only snap-shots of what may be dynamic systems. We report here on four surveys, carried out over a period of 12 years, of helminths of spiny mice (Acomys dimidiatus), the numerically dominant rodents inhabiting dry montane wadis in the Sinai Peninsula. With host age (age-dependent effects on prevalence and abundance were prominent) and sex (female bias in abundance in helminth diversity and in several taxa including Cestoda) taken into consideration, we focus on the relative importance of temporal and spatial effects on helminth infracommunities. We show that site of capture is the major determinant of prevalence and abundance of species (and higher taxa) contributing to helminth community structure, the only exceptions beingStreptopharausspp. andDentostomella kuntzi.We provide evidence that most (notably the Spiruroidea,Protospirura muricola,Mastophorus murisandGongylonema aegypti, but with exceptions among the Oxyuroidae, e.g.Syphacia minuta), show elements of temporal-site stability, with a rank order of measures among sites remaining similar over successive surveys. Hence, there are some elements of predictability in these systems.


2019 ◽  
Vol 94 ◽  
pp. 102068 ◽  
Author(s):  
Guiwen Liu ◽  
Xizi Wang ◽  
Jianping Gu ◽  
Yong Liu ◽  
Tao Zhou

Water ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 265
Author(s):  
Chengjing Liu ◽  
Yuanmei Jiao ◽  
Dongmei Zhao ◽  
Yinping Ding ◽  
Zhilin Liu ◽  
...  

Landform changes caused by human activities can directly affect the recharge of groundwater, and are reflected in the temporal and spatial changes in groundwater stable isotope composition. These changes are particularly evident in high-intensity farming areas. In this study, we tested and analyzed groundwater stable isotope samples at different elevations of rice terraces in a typical agricultural watershed of the Hani Terraces, a World Heritage Cultural Landscape in southwest China. Thus, we determined the characteristic variations and factors that influence the temporal and spatial effects on groundwater stable isotopes in the Hani Terraces, which are under the influence of high-intensity farming activities. The elevation gradients of δ18O and δ2H in groundwater are significantly increased due to farming activities. The values were 0.88‰ (100 m)−1 and −4.5‰ (100 m)−1, respectively, and they changed with time. The groundwater circulation cycle is approximately three months. We also used the special temporal and spatial variation characteristics of the groundwater isotopes as a way to evaluate the source and periodic changes of groundwater recharge. In addition, high-intensity rice farming activities, such as ploughing every year from October to January can increase the supply of terraced water to groundwater, thus ensuring the sustainability of rice cultivation in the terraces during the dry season. This demonstrates the role of human wisdom in the sustainable and benign transformation of surface cover and the regulation of groundwater circulation.


Perception ◽  
1997 ◽  
Vol 26 (1_suppl) ◽  
pp. 1-1 ◽  
Author(s):  
N Takahashi ◽  
R Groner

The effect of temporal and spatial overlap on globally coherent motion was studied. Two lines oriented 60° and 300°, respectively, moved horizontally, creating the perception of either an integrated coherent motion on the horizontal axis, or two distinct component motions orthogonal to each line. The overlap of presentation time was varied: 100% (simultaneous), 50% (partial overlap), and 0% (successive). With respect to the spatial condition, the two lines were presented (1) superimposed in a single aperture, (2) in two adjacent apertures, or (3) in two distant apertures. We found that, when the lines were presented simultaneously, the percentage of perceived coherent motion was consistently high, regardless of spatial condition. However, when temporal overlap was lower, the percentage of perceived coherent motion decreased according to the number of apertures and their distance. In the 0% condition there were fewer than 50% coherent motions reported, even in the single-aperture condition. An effect of the intersection of the two lines was observed in the 50% condition, but not in the 100% condition. These and other findings suggest that timing is the most critical factor, and spatial effects, as expressed by the distance between the lines and by the intersections, play a less important role.


1992 ◽  
Vol 9 (8) ◽  
pp. 1234 ◽  
Author(s):  
J. Peatross ◽  
D. D. Meyerhofer ◽  
M. V. Fedorov

1975 ◽  
Vol 40 (3) ◽  
pp. 939-946
Author(s):  
Paul Tyson ◽  
Ken Goldstein

Five subjects were asked to report the brightness and duration of afterimages formed in a region where a border had previously been exposed. The temporal and spatial aftereffects of the border on the formation of the afterimage varied with the duration of the border and these aftereffects were within the area predicted by a photochemical bleaching hypothesis. In addition to these major findings, the experiment yielded some surprising secondary observations. For example, increasing the degree of bleaching or light adaptation made the afterimage brighter if it was on the right side but decreased the brightness if on the left. The difference between afterimages on the right and left sides was discussed in terms of spatial effects of borders and laterality differences.


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