spatial reference
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2021 ◽  
Vol 4 ◽  
pp. 1-8
Author(s):  
Bashkim Idrizi

Abstract. The state Coordinate Reference System (CRS) of the Republic of North Macedonia (RNM) has been established a century ago, by the Military Geographic Institute of the Yugoslavia Kingdom. It is in official usage entire period up to day. In international public EPSG registry of geodetic datums, spatial reference systems, Earth ellipsoids, coordinate transformations and related units of measurement, CRS for RNM is recognizable within 3 EPSG codes 6204, 6316 and 8679.First code EPSG 6204 represents current state CRS for the entire country area, based on current law, however unfortunately this CRS is official by the law but it is not used for developing the official spatial data published in geoportals of Agency for Real Estate Cadastre (AREC) and NSDI geoportal of RNM. The second code EPSG 6316 is defined to be used for 6 countries of former Yugoslavia that covers area between 19.5°E up to 22.5°E longitude, which does not correspond with the practical and official usage of CRS for working with spatial data in RNM and CRS law definition in RNM. Third code EPSG 8679 has never been used in RNM, which covers eastern part of RNM and Serbia beginning from 22.5°E.Beside of problems with EPSG codes, default transformation parameters of EPSG 6316 have low accuracy and can not be used for data overlapping with open layers. Therefore, redefined new EPSG codes for state CRS of RNM are proposed in this paper.


2021 ◽  
Vol 15 ◽  
Author(s):  
Guohua Li ◽  
Yu Wang ◽  
Fang Cao ◽  
Dawei Wang ◽  
Limin Zhou ◽  
...  

Sevoflurane (SEVO) is a highly fluorinated methyl isopropyl ether used as an inhalational anesthetic for general anesthesia. Previous studies have shown that SEVO may induce impaired memory and recognition ability and may be associated with neurodegenerative disease, e.g., Alzheimer’s disease (AD). However, the underlying mechanism remains unknown. Here, we used a mouse AD model, APP/PS1, to study the effects of SEVO on neurodegeneration occurring in AD. We found that SEVO exposure significantly impaired the spatial reference memory, sensorimotor, and cognitive function of the mice. Mechanistically, we found that SEVO induced formation of NOD-, LRR- and pyrin domain-containing protein 3 (NLRP3) inflammasome and its downstream caspase 1-mediated production of IL-1β and IL-18, which subsequently deactivated brain-derived neurotrophic factor (BDNF) to promote neurodegeneration. Together, these data suggest that NLRP3 inflammasome is essential for SEVO-induced AD.


Sensors ◽  
2021 ◽  
Vol 21 (23) ◽  
pp. 7831
Author(s):  
Oktawia Lewicka ◽  
Mariusz Specht ◽  
Andrzej Stateczny ◽  
Cezary Specht ◽  
David Brčić ◽  
...  

The integration of geospatial data in hydrography, performed using different measurement systems, involves combining several study results to provide a comprehensive analysis. Each of the hydroacoustic and optoelectronic systems is characterised by a different spatial reference system and the method for technical implementation of the measurement. Therefore, the integration of hydrographic data requires that problems in selected fields of electronics, geodesy and physics (acoustics and optics) be solved. The aim of this review is to present selected fusion methods applying the data derived from Global Navigation Satellite System (GNSS), Real Time Kinematic (RTK) measurements, hydrographic surveys, a photogrammetric pass using unmanned vehicles and Terrestrial Laser Scanning (TLS) and compare their accuracy. An additional goal is the evalution of data integration methods according to the International Hydrographic Organization (IHO) S-44 standard. The publication is supplemented by implementation examples of the integration of geospatial data in the Geographic Information System (GIS). The methods described indicate the lack of a uniform methodology for data fusion due to differences in both the spatial reference systems and the techniques used. However, the integration of hydroacoustic and optoelectronic data allows for high accuracy geospatial data to be obtained. This is confirmed by the methods cited, in which the accuracy of integrated geospatial data was in the order of several centimetres.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Sheng-Yi Hsu ◽  
Bartosz Jura ◽  
Mau-Hsiang Shih ◽  
Pierre Meyrand ◽  
Feng-Sheng Tsai ◽  
...  

AbstractEvidence indicates that sharp-wave ripples (SWRs) are primary network events supporting memory processes. However, some studies demonstrate that even after disruption of awake SWRs the animal can still learn spatial task or that SWRs may be not necessary to establish a cognitive map of the environment. Moreover, we have found recently that despite a deficit of sleep SWRs the APP/PS1 mice, a model of Alzheimer’s disease, show undisturbed spatial reference memory. Searching for a learning-related alteration of SWRs that could account for the efficiency of memory in these mice we use convolutional neural networks (CNN) to discriminate pre- and post-learning 256 ms samples of LFP signals, containing individual SWRs. We found that the fraction of samples that were correctly recognized by CNN in majority of discrimination sessions was equal to ~ 50% in the wild-type (WT) and only 14% in APP/PS1 mice. Moreover, removing signals generated in a close vicinity of SWRs significantly diminished the number of such highly recognizable samples in the WT but not in APP/PS1 group. These results indicate that in WT animals a large subset of SWRs and signals generated in their proximity may contain learning-related information whereas such information seem to be limited in the AD mice.


2021 ◽  
Author(s):  
Jie Huang ◽  
Xiaoyu Tang ◽  
Aijun Wang ◽  
Ming Zhang

Abstract Neuropsychological studies have demonstrated that the preferential processing of near-space and egocentric representation is associated with the self-prioritization effect (SPE). However, relatively little is known concerning whether the SPE is superior to the representation of egocentric frames or near-space processing in the interaction between spatial reference frames and spatial domains. The present study adopted the variant of the shape-label matching task (i.e., color-label) to establish an SPE, combined with a spatial reference frame judgment task, to examine how the SPE leads to preferential processing of near-space or egocentric representations. Surface-based morphometry analysis was also adopted to extract the cortical thickness of the ventral medial prefrontal cortex (vmPFC) to examine whether it could predict differences in the SPE at the behavioral level. The results showed a significant SPE, manifested as the response of self-associated color being faster than that of stranger-associated color. Additionally, the SPE showed a preference for near-space processing, followed by egocentric representation. More importantly, the thickness of the vmPFC could predict the difference in the SPE on reference frames, particularly in the left frontal pole cortex and bilateral rostral anterior cingulate cortex. These findings indicated that the SPE showed a prior entry effect for information at the spatial level relative to the reference frame level, providing evidence to support the structural significance of the self-processing region. The present study also further clarified the priority in SPE processing and role of the SPE within the real spatial domain.


Author(s):  
Bill Palmer ◽  
Dorothea Hoffmann ◽  
Joe Blythe ◽  
Alice Gaby ◽  
Bill Pascoe ◽  
...  

2021 ◽  
pp. 1-22
Author(s):  
Emilia Tuuri

Abstract This article describes variation in the use of frames of reference (FoRs; object-centred, viewpoint-centred, and geocentric, as in Holistic Spatial Semantics) in Finnish descriptions of motion and connects questions of variation to a typological framework. Recent research has described the choice of FoRs as a process with multiple factors. This complexity and controlling for the main variables posited in the literature create the starting point for the current study that explores factors affecting the choice of FoRs in motion situations and within speakers of the same language. The data were elicited from 50 native speakers of Finnish by using video stimuli. The informants were (mostly) formally educated young adults living in urban surroundings. The analysis reveals considerable variation in individual coding strategies, especially in the inclusion of the speaker’s viewpoint. It also considers variation with respect to different types of trajectories and cross-linguistic differences in the resources of spatial reference.


2021 ◽  
Author(s):  
Benjamin Pitt ◽  
Alexandra Carstensen ◽  
Isabelle Boni ◽  
Steven T. Piantadosi ◽  
Edward Gibson

The physical properties of space may be universal, but the way people conceptualize space is variable. In some groups, people tend to use egocentric space (e.g. left, right) to encode the locations of objects, while in other groups, people encode the same spatial scene using allocentric space (e.g. upriver, downriver). These different spatial frames of reference (FoRs) characterize the way people talk about spatial relations and the way they think about them, even when they are not using language. Although spatial language and spatial reasoning tend to covary, the root causes of this variation are unclear. Here we propose that variation in FoR use partly reflects the discriminability of the relevant spatial continua. In an initial test of this proposal in a group of indigenous Bolivians, we compared FoR use across spatial axes that are known to differ in discriminability. In both verbal and nonverbal tests, participants spontaneously used different FoRs on different spatial axes: On the lateral axis, where egocentric (left-right) discrimination is difficult, their spatial behavior and language was predominantly allocentric; on the sagittal axis, where egocentric (front-back) discrimination is relatively easy, they were predominantly egocentric. These findings challenge the claim that each language group can be characterized by a predominant spatial frame of reference. Rather, both spatial memory and language can differ categorically across axes, even within the same individuals. We suggest that differences in spatial discrimination can explain differences in both spatial memory and language within and across human groups.


2021 ◽  
Author(s):  
Indrajith R Nair ◽  
Dipanjan Roy

Animals predominantly use salient visual cues (landmarks) for efficient navigation over other sensory modalities. When the relative position of the visual cues is altered, the hippocampal population exhibits heterogeneous responses and constructs context-specific spatial maps. Another critical factor that can strongly modulate spatial representation is the presence of reward. Reward features can drive behavior and are known to bias spatial attention. However, it is unclear whether reward flavors are used for spatial reference in the presence of distal cues and how the hippocampus population dynamics changes when the association between reward flavors and distal cues is altered. We investigated these questions by recording place cells from the CA1 while the rats ran in an environment with the conflicting association between reward flavors and distal cues. We report that the hippocampal place cells coherently and dynamically bind to reward flavors or distal cues across sessions, but not simultaneously suggesting the use of a single spatial map. We found that place cells maintained their spatial offset in the cue conflict conditions, thus showing a robust spatial coupling featuring an attractor-like property in the CA1. When the textures were added on the track, the coherency of the CA1 is degraded, as the hippocampus showed a heterogeneous response and weak spatial coupling of co-recorded cells suggesting a break away from the attractor network. These results indicate that reward flavors alone may be used for spatial reference but may not cause sufficient input difference to create context-specific spatial maps in the CA1.


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