Spatial Relations (spatial + relation)

Distribution by Scientific Domains


Selected Abstracts


Effects of lorazepam on visual perceptual abilities

HUMAN PSYCHOPHARMACOLOGY: CLINICAL AND EXPERIMENTAL, Issue 3 2008
S. Pompéia
Abstract Objective To evaluate the effects of an acute dose of the benzodiazepine (BZ) lorazepam in young healthy volunteers on five distinguishable visual perception abilities determined by previous factor-analytic studies. Methods This was a double-blind, cross-over design study of acute oral doses of lorazepam (2,mg) and placebo in young healthy volunteers. We focused on a set of paper-and-pencil tests of visual perceptual abilities that load on five correlated but distinguishable factors (Spatial Visualization, Spatial Relations, Perceptual Speed, Closure Speed, and Closure Flexibility). Some other tests (DSST, immediate and delayed recall of prose; measures of subjective mood alterations) were used to control for the classic BZ-induced effects. Results Lorazepam impaired performance in the DSST and delayed recall of prose, increased subjective sedation and impaired tasks of all abilities except Spatial Visualization and Closure Speed. Only impairment in Perceptual Speed (Identical Pictures task) and delayed recall of prose were not explained by sedation. Conclusion Acute administration of lorazepam, in a dose that impaired episodic memory, selectively affected different visual perceptual abilities before and after controlling for sedation. Central executive demands and sedation did not account for results, so impairment in the Identical Pictures task may be attributed to lorazepam's visual processing alterations. Copyright © 2008 John Wiley & Sons, Ltd. [source]


Six-Month-Old Infants' Categorization of Containment Spatial Relations

CHILD DEVELOPMENT, Issue 3 2003
Marianella Casasola
Six-month-old infants' ability to form an abstract category of containment was examined using a standard infant categorization task. Infants were habituated to 4 pairs of objects in a containment relation. Following habituation, infants were tested with a novel example of the familiar containment relation and an example of an unfamiliar relation. Results indicate that infants look reliably longer at the unfamiliar versus familiar relation, indicating that they can form a categorical representation of containment. A second experiment demonstrated that infants do not rely on object occlusion to discriminate containment from a support or a behind spatial relation. Together, the results indicate that by 6 months, infants can recognize a containment relation from different angles and across different pairs of objects. [source]


Young Infants' Performance in the Object-Variation Version of the Above-Below Categorization Task: A Result of Perceptual Distraction or Conceptual Limitation?

INFANCY, Issue 3 2002
Paul C. Quinn
Five experiments were conducted to examine the performance of young infants on above versus below categorization tasks. Experiments 1 and 2 showed that infants did not form abstract categorical representations for above and below when familiarized with different objects depicted in a constant spatial relation relative to a horizontal bar and tested on a novel object depicted in the familiar and novel spatial relation. Experiments 3 through 5 examined perceptual-attentional distraction versus conceptually based generalization explanations for young infant performance in the object-variation version of the above-below categorization task. Experiments 3 and 4 demonstrated that infants still did not form abstract categorical representations for above and below when object variation was removed from the familiarization trials or when object novelty was reduced during the preference test trials. However, Experiment 5 showed that 3- and 4-month-olds succeeded on the above versus below categorization task when familiarized with object variation and preference tested with a familiar versus novel object-bar relation. These results indicate that young infants can form categorical representations for above and below in the object-variation version of the above-below categorization task, but that such representations are specific to the particular objects presented. Young infant performance in the object-variation version of the above-below categorization task thus reflects a conceptually based generalization limit rather than a problem of perceptual-attentional distraction. [source]


Mature teratoma of the uterine cervix with lymphoid hyperplasia

PATHOLOGY INTERNATIONAL, Issue 5 2003
Sung-chul Lim
A rare case of an extragonadal teratoma, which occurred primarily in the uterus, is described. The tumor developed in the uterine cervix as a conventional cervical polyp, 3 months after an elective abortion in a 27-year-old woman. Microscopically, the solid 2.2 × 1.8 × 1.5 cm mass was a mature teratoma with exuberant lymphoid elements. It consisted of ectodermal, mesodermal and endodermal derivatives. The lymphoid elements may have been a lymphoid hyperplasia, a chronic inflammatory reaction or a component of the teratoma. However, as the lymphoid tissues had no spatial relation to the teratomatous components, the possibility of a teratomatous element was excluded. This could be regarded as a result of an immunological reaction to the tissues composing the tumor, rather than just a chronic inflammatory response because the lymphoid reaction was present in the tumor, the tumor,host interface and the perivascular areas. Because of the patient's history of an abortion and a lymphoid reaction, the possibility of fetal remnants implantation was raised, so DNA typing to compare the teratoma portion with a normal portion of the host was performed. We found the teratoma portions to be in accordance with that of the host, and hence ruled out fetal remnants implantation. This case showed that a mature teratoma of the uterine cervix may manifest as a feature of implanted fetal tissue. In addition, a real teratoma should be included in the differential diagnosis of uterine teratomatous lesion, even when detected in patients with a recent history of pregnancy and lymphoid hyperplasia. [source]


Six-Month-Old Infants' Categorization of Containment Spatial Relations

CHILD DEVELOPMENT, Issue 3 2003
Marianella Casasola
Six-month-old infants' ability to form an abstract category of containment was examined using a standard infant categorization task. Infants were habituated to 4 pairs of objects in a containment relation. Following habituation, infants were tested with a novel example of the familiar containment relation and an example of an unfamiliar relation. Results indicate that infants look reliably longer at the unfamiliar versus familiar relation, indicating that they can form a categorical representation of containment. A second experiment demonstrated that infants do not rely on object occlusion to discriminate containment from a support or a behind spatial relation. Together, the results indicate that by 6 months, infants can recognize a containment relation from different angles and across different pairs of objects. [source]


Optimizing Structure Preserving Embedded Deformation for Resizing Images and Vector Art

COMPUTER GRAPHICS FORUM, Issue 7 2009
Qi-xing Huang
Abstract Smart deformation and warping tools play an important part in modern day geometric modeling systems. They allow existing content to be stretched or scaled while preserving visually salient information. To date, these techniques have primarily focused on preserving local shape details, not taking into account important global structures such as symmetry and line features. In this work we present a novel framework that can be used to preserve the global structure in images and vector art. Such structures include symmetries and the spatial relations in shapes and line features in an image. Central to our method is a new formulation of preserving structure as an optimization problem. We use novel optimization strategies to achieve the interactive performance required by modern day modeling applications. We demonstrate the effectiveness of our framework by performing structure preservation deformation of images and complex vector art at interactive rates. [source]


Spatial Information: Classification and Applications in Building Design

COMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 4 2002
Tang-Hung Nguyen
Physical properties of building components are usually represented in building data models by their three-dimensional geometry and topology,also called spatial information. While geometric data of building components can be manipulated and managed by a computer-aided design (CAD) interface, their spatial relations (or topological information) are conventionally represented in a manual fashion into data models. The manual data representation, however, is inherently a complex and challenging task due to the wide variety of spatial relationships. Thus, topological information should be classified and modeled in such a way that the required spatial data for a particular design task can be automatically retrieved. This paper attempts to identify and classify various topological information commonly used in building design and construction into more specific categories (e.g., adjacency, connection, containment, separation, and intersection) to support automatic deduction of the spatial information in a computer-based building design system. The paper also discusses typical applications of the topological relations to different design activities. Finally, the development of deduction algorithms and the proposed building design system are briefly described. [source]


Customized mandibular orthotics in the prevention of concussion/mild traumatic brain injury in football players: a preliminary study

DENTAL TRAUMATOLOGY, Issue 5 2009
G. Dave Singh
However, previous investigations have primarily studied non-customized mouthguards without dental/temporo-mandibular joint examinations of the subjects. Therefore, the aim of this study is to determine whether the use of a customized mandibular orthotic after temporo-mandibular joint assessment reduces the incidence of concussion/mild traumatic brain injuries in high-school football players. Materials and methods:, Using a longitudinal, retrospective design, data were collected from a cohort of football players (n = 28) over three seasons using a questionnaire. The mean age of the sample prior to the use of the customized mandibular orthotic was 17.3 years ± 1.9. Prior to deployment, dental records and temporo-mandibular joint evaluations were undertaken, as well as neurocognitive assessment, including history of concussion/mild traumatic brain injuries. After establishing optimal jaw position, a customized mandibular orthotic was fabricated to the new spatial relations. Results:, The mean age of the sample after three seasons was 19.7 years ± 2.0. Prior to the use of the customized mandibular orthotic, the mean self-reported incidence of concussion/mild traumatic brain injuries was 2.1 ± 1.4 concussive events. After the deployment of the customized mandibular orthotic the number of concussive events fell to 0.11 ± 0.3 with an odds ratio of 38.33 (95% CI 8.2,178.6), P < 0.05. Conclusion:, The preliminary results of this study suggest that a customized mandibular orthotic may decrease the incidence of concussion/mild traumatic brain injuries in high- school football athletes, but a comprehensive study is required to confirm these initial findings. Furthermore, additional research is necessary to indicate the possible mode(s) of action of a customized mandibular orthotic in the prevention of concussion/mild traumatic brain injuries. [source]


Seeing the big picture: map use and the development of spatial cognition

DEVELOPMENTAL SCIENCE, Issue 3 2000
David H. Uttal
This paper considers the relation between the development of spatial cognition and children's use of maps and models. A new theoretical perspective is presented that takes into account the influences of maps on the development of spatial cognition. Maps provide a perspective on spatial information that differs in important ways from the perspective gained from direct experience navigating in the world. Using and thinking about maps may help children to acquire abstract concepts of space and the ability to think systematically about spatial relations that they have not experienced directly. In addition, exposure to maps may help children to think about multiple spatial relations among multiple locations. The results of previous studies that have demonstrated developmental differences in children's cognition of large-scale environments are examined from this theoretical perspective. This review suggests that the development of spatial cognition consists partly of the acquisition of models of large-scale space, and that maps influence the development of the modern Western model. [source]


Spatial firing properties of lateral septal neurons

HIPPOCAMPUS, Issue 8 2006
Yusaku Takamura
Abstract The present study describes the spatial firing properties of neurons in the lateral septum (LS). LS neuronal activity was recorded in rats as they performed a spatial navigation task in an open field. In this task, the rat acquired an intracranial self-stimulation reward when it entered a certain place, a location that varied randomly from trial to trial. Of 193 neurons recorded in the LS, 81 showed place-related activity. The majority of the tested neurons changed place-related activity when spatial relations between environmental cues were altered by rotating intrafield (proximal) cues. The comparison of place activities between LS place-related neurons recorded in the present study and hippocampal place cells recorded in our previous study, using identical behavioral and recording procedures, revealed that spatial parameters (spatial information content, coherence, and cluster size) were smaller in the LS than in the hippocampus. Of the 193 LS neurons, 86 were influenced by intracranial self-stimulation rewards; 31 of these 86 were also place-related. These results, together with previous anatomical and behavioral observations, suggest that the spatial information sent from the hippocampus to the LS is modulated by and interacts with signals related to reward in the LS. © 2006 Wiley-Liss, Inc. [source]


Accessing the mental space,Spatial working memory processes for language and vision overlap in precuneus

HUMAN BRAIN MAPPING, Issue 5 2008
Mikkel Wallentin
Abstract The "overlapping systems" theory of language function argues that linguistic meaning construction crucially relies on contextual information provided by "nonlinguistic" cognitive systems, such as perception and memory. This study examines whether linguistic processing of spatial relations established by reading sentences call on the same posterior parietal neural system involved in processing spatial relations set up through visual input. Subjects read simple sentences, which presented two agents in relation to each other, and were subsequently asked to evaluate spatial (e.g., "Was he turned towards her?") and equally concrete nonspatial content (e.g., "Was he older than her?"). We found that recall of the spatial content relative to the nonspatial content resulted in higher BOLD response in a dorsoposterior network of brain regions, most significantly in precuneus, strikingly overlapping a network previously shown to be involved in recall of spatial aspects of images depicting similar scenarios. This supports a neurocognitive model of language function, where sentences establish meaning by interacting with the perceptual and working memory networks of the brain. Hum Brain Mapp 2008. © 2007 Wiley-Liss, Inc. [source]


Exposure modeling on a river basin scale in support of risk assessment for chemicals in european river basins

INTEGRATED ENVIRONMENTAL ASSESSMENT AND MANAGEMENT, Issue 1 2009
Jos van Gils
Abstract Following the 2000 European Water Framework Directive and recent insights into sediment management on a river basin scale, we discuss in this paper an exposure model aiming to support a risk assessment for chemicals on a basin-wide scale. It establishes spatial relations between causes (pollution sources) and effects (ecological risk), taking into account the geometry, hydrology, and fine sediment dynamics of European river basins. The model, called EXPOBASIN, explicitly takes into account the interaction of chemicals with fine sediment particles, which is important for many policy-relevant chemicals, such as trace metals and polycyclic aromatic hydrocarbons, and it addresses the potential release of historically polluted sediments as a result of extreme floods, which is a major concern in different European river basins. Bioavailability and bioaccumulation are included in the assessment. As a result, the exposure can be quantified not only in terms of water concentrations, but also in terms of sediment concentrations and concentrations in biota. The primary question to be answered by EXPOBASIN is how chemicals, pollution sources, or both rank quantitatively and objectively on a basin-wide scale. Near the end of 2009, the tool will become available to all European water managers and their technical advisors, as a result of the European Union 6th Framework Programme project MODELKEY The calibration and validation of EXPOBASIN has only just started and will be completed in 2008/2009. Applications to 3 case study areas are planned in this respect. This paper presents the key building blocks of EXPOBASIN and shows some sample results illustrating the raking of pollution sources and chemicals. At the end of the paper, some perspectives for future developments are outlined. [source]


Fast gradual matching measure for image retrieval based on visual similarity and spatial relations

INTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 7 2006
Jean-François Omhover
In this article, we propose a new method to retrieve images containing a request set of regions. The user is asked to specify a set of regions belonging to a single image. Then this request set of regions is compared to the sets of the regions of the images in the database. We propose a comparison measure that not only evaluates the similarity of regions one to the other, but that also takes into account the spatial configuration of the regions. The spatial structure of the regions is represented by means of fuzzy spatial relations, like horizontal and vertical disposal and connexity. © 2006 Wiley Periodicals, Inc. Int J Int Syst 21: 711,723, 2006. [source]


GATED COMMUNITIES AND SPATIAL INEQUALITY

JOURNAL OF URBAN AFFAIRS, Issue 2 2007
ELENA VESSELINOV
ABSTRACT:,In this article we analyze gated communities as a nexus of social and spatial relations within the context of urban inequality. We apply Tickamyer's (2000) sociological framework for incorporating space into the study of inequality, which allows us to substantiate the arguments that the process of gating increases urban inequality. The contributions of this article are three: (1) We generate a new systematic theoretical approach toward the study of gated communities, which we consider as middle range theory; (2) We argue that gated communities reproduce the existing levels of social stratification and that they also define a new, permanent differentiation order in the spatial organization of cities in the United States (in this respect we also arrive at six hypotheses, which can be tested in future research); (3) We introduce the term "gating machine," where the combination of the interests and actions of local governments, real estate developers, the media, and consumers suggest that prevailing structural conditions assure the future proliferation of gated communities. [source]


The Phenomenal Content of Experience

MIND & LANGUAGE, Issue 2 2006
Athanassios Raftopoulos
We argue that a distinction can be drawn between representations with conceptual and nonconceptual content. The distinction is based on perceptual mechanisms that retrieve information in conceptually unmediated ways. The representational contents of the states induced by these mechanisms that are available to a type of awareness called phenomenal awareness constitute the phenomenal content of experience. The phenomenal content of perception contains the existence of objects as separate things that persist in time and time, spatiotemporal information, and information regarding relative spatial relations, motion, surface properties, shape, size, orientation, color, and their functional properties. [source]


Lymphatic/Blood Endothelial Cell Connections at the Capillary Level in Adult Rat Mesentery

THE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 10 2010
Jennifer L. Robichaux
Abstract Analyses of microvascular networks with traditional tracer filling techniques suggest that the blood and lymphatic systems are distinct without direct communications, yet involvement of common growth factors during angiogenesis and lymphangiogenesis suggest that interactions at the capillary level are possible. To investigate the structural basis for lymphatic/blood endothelial cell connections during normal physiological growth, the objective of this study was to characterize the spatial relations between lymphatic and blood capillaries in adult rat mesenteric tissue. Using immunohistochemical methods, adult male Wistar rat mesenteric tissues were labeled with antibodies against PECAM (an endothelial marker) and LYVE-1, Prox-1, or Podoplanin (lymphatic endothelial markers) or NG2 (a pericyte marker). Positive PECAM labeling identified apparent lymphatic/blood endothelial cell connections at the capillary level characterized by direct contact or direct alignment with one another. In PECAM labeled networks, a subset of the lymphatic and blood capillary blind ends were connected with each other. Intravital imaging of FITC-Albumin injected through the femoral vein did not identify lymphatic vessels. At contact sites, lymphatic endothelial markers did not extend along blood capillary segments. However, PECAM positive lymphatic sprouts, structurally similar to blood capillary sprouts, lacked observable lymphatic marker labeling. These observations suggest that nonlumenal lymphatic/blood endothelial cell interactions exist in unstimulated adult microvascular networks and highlight the potential for lymphatic/blood endothelial cell plasticity. Anat Rec 293:1629,1638, 2010. © 2010 Wiley-Liss, Inc. [source]


A Bayesian Spatial Multimarker Genetic Random-Effect Model for Fine-Scale Mapping

ANNALS OF HUMAN GENETICS, Issue 5 2008
M.-Y. Tsai
Summary Multiple markers in linkage disequilibrium (LD) are usually used to localize the disease gene location. These markers may contribute to the disease etiology simultaneously. In contrast to the single-locus tests, we propose a genetic random effects model that accounts for the dependence between loci via their spatial structures. In this model, the locus-specific random effects measure not only the genetic disease risk, but also the correlations between markers. In other words, the model incorporates this relation in both mean and covariance structures, and the variance components play important roles. We consider two different settings for the spatial relations. The first is our proposal, relative distance function (RDF), which is intuitive in the sense that markers nearby are likely to correlate with each other. The second setting is a common exponential decay function (EDF). Under each setting, the inference of the genetic parameters is fully Bayesian with Markov chain Monte Carlo (MCMC) sampling. We demonstrate the validity and the utility of the proposed approach with two real datasets and simulation studies. The analyses show that the proposed model with either one of two spatial correlations performs better as compared with the single locus analysis. In addition, under the RDF model, a more precise estimate for the disease locus can be obtained even when the candidate markers are fairly dense. In all simulations, the inference under the true model provides unbiased estimates of the genetic parameters, and the model with the spatial correlation structure does lead to greater confidence interval coverage probabilities. [source]


Social agency and networked spatial relations in sustainable agriculture

AREA, Issue 2 2009
A Trauger
Agriculture in the USA is in social and economic crisis, but sustainable agriculture is gaining unprecedented popularity among producers and consumers. This article examines the agency articulated by farmers and activists in the sustainable agriculture community in Pennsylvania to exploit ruptures in the conventional food system and develop new forms of food provisioning in local economies. Actor-network theory offers roads out of structure/agency dialectics and proposes new possibilities for understanding structure as a network, and agency as the outcome of networking. The research shows agency to be an outcome of collectivities, but is also contingent on leadership, partially distributed throughout the network and not necessarily emancipatory for all enrolled actors. [source]


Narrative analysis as a strategy for understanding interview talk in geographic research

AREA, Issue 1 2005
Janine L Wiles
Narrative analysis produces strategies to inform the conduct, interpretation and presentation of interview talk, and encourages and enables researchers to take account of research participants' own evaluations. We suggest this to be a useful method for geographers because it focuses on how people talk about and evaluate places, experiences and situations, as well as what they say. With an example from health geography, we show how it allows for interactive texts, thus providing a tool for geographers doing qualitative research to connect intimate details of experience to broader social and spatial relations. [source]


Origin and evolution of primate social organisation: a reconstruction

BIOLOGICAL REVIEWS, Issue 3 2000
ALEXANDRA E. MÜLLER
ABSTRACT The evolution and origin of primate social organisation has attracted the attention of many researchers, and a solitary pattern, believed to be present in most nocturnal prosimians, has been generally considered as the most primitive system. Nocturnal prosimians are in fact mostly seen alone during their nightly activities and therefore termed' solitary foragers', but that does not mean that they are not social. Moreover, designating their social organisation as' solitary', implies that their way of life is uniform in all species. It has, however, emerged over the last decades that all of them exhibit not only some kind of social network but also that those networks differ among species. There is a need to classify these social networks in the same manner as with group-living (gregarious) animals if we wish to link up the different forms of primate social organisation with ecological, morphological or phylogenetic variables. In this review, we establish a basic classification based on spatial relations and sociality in order to describe and cope properly with the social organisation patterns of the different species of nocturnal prosimians and other mammals that do not forage in cohesive groups. In attempting to trace the ancestral pattern of primate social organisation, the Malagasy mouse and dwarf lemurs and the Afro-Asian bushbabies and lorises are of special interest because they are thought to approach the ancestral conditions most closely. These species have generally been believed to exhibit a dispersed harem system as their pattern of social organisation (,dispersed' means that individuals forage solitarily but exhibit a social network). Therefore, the ancestral pattern of primate social organisation was inferred to be a dispersed harem. In fact, new field data on cheirogaleids combined with a review of patterns of social organisation in strepsirhines (lemurs, bushbabies and lorises) revealed that they exhibit either dispersed multi-male systems or dispersed monogamy rather than a dispersed harem system. Therefore, the concept of a dispersed harem system as the ancestral condition of primate social organisation can no longer be supported. In combination with data on social organisation patterns in ,primitive' placentals and marsupials, and in monotremes, it is in fact most probable that promiscuity is the ancestral pattern for mammalian social organisation. Subsequently, a dispersed multi-male system derived from promiscuity should be regarded as the ancestral condition for primates. We further suggest that the gregarious patterns of social organisation in Aotus and Avahi, and the dispersed form in Tarsius evolved from the gregarious patterns of diurnal primates rather than from the dispersed nocturnal type. It is consequently proposed that, in addition to Aotus and Tarsius, Avahi is also secondarily nocturnal. [source]


Space Matters: The Power and Practice of Space

COMMUNICATION THEORY, Issue 1 2003
Raka Shome
This article argues for the importance of a spatial perspective in critical communication studies. It suggests that a focus on spatial relations of power enables scholars of communication and culture to understand and theorize the complex ways in which identities are being reproduced in our current moment of globalization. The article suggests that, instead of theorizing cultural power only through the category of identity, we need to adopt a spatial perspective on power that may better enable us to theorize various relations of identity and culture. [source]