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Agglomeration economies are manifested in geographical concentration of firms, as stated by Agglomeration Theory. The objective of this paper was to examine the proximity and concentration of firms in continuous space and in specific directions for the mapping of potential industrial clusters, through an unprecedented approach. The methods used were the indicator semivariogram, anisotropy modeling and kriging interpolation. The geostatistical approach was initially applied in a simulated data with patterns known a priori: random and clusters. Then it was validated with real data of roasted coffee industry in Minas Gerais, Brazil. Each dataset was tested in isotropic and anisotropic scenarios. Geostatistics was sufficient to detect patterns of randomness and spatial dependence, measure the extent of proximity between firms, identify regions with a high level of industrial concentration on the map and estimate an index of concentration at the firm level. The results also advanced the specialized literature by indicating that the anisotropic scenarios, which adjusts the directional bias, better described the reality of the phenomena compared to the isotropic ones. Error measures in anisotropic scenarios were between 7 and 30% more accurate. It was concluded that the direction can be a determinant of the theory of agglomerations and that geostatistics can be useful for mapping potential industry clusters. [ABSTRACT FROM AUTHOR]

Becoming literate has been argued to have a range of social, economic and psychological effects. Less examined is the extent to which repercussions of becoming literate may vary as a function of writing system variation. A salient way in which writing systems differ is in their directionality. Recent studies have claimed that directional biases in a variety of spatial domains are attributable to reading and writing direction. This claim is the focus of the present paper, which considers the scope and possible mechanisms underlying script directionality effects in spatial cognition, with particular attention to domains with real-world relevance. Three questions are addressed: (1) What are possible mediating and moderator variables relevant to script directionality effects in spatial cognition? (2) Does script directionality exert a fixed or a malleable effect? and (3) How can script directionality effects be appropriately tested? After discussing these questions in the context of specific studies, we highlight general methodological issues in this literature and provide recommendations for the design of future research. [ABSTRACT FROM AUTHOR]

Animals frequently encounter situations in which they can choose to move either left or right. Consistent preferences to move a specific direction may be associated with lateralization, or the asymmetric structure and function of the brain and nervous system. Other lateralized behaviors commonly occur across taxa, possibly reflecting a selective advantage of cerebral specialization. Yet, lateralization and possible directional biases are rarely tested within an ecologically relevant context, such as movement, or while animals are making decisions on a larger scale. Here, we quantify to what extent wild food-caching mountain chickadees (Poecile gambeli) in their natural environment demonstrate consistent directional biases in movement when learning a spatial task. Directional bias was estimated from the direction (left or right) that birds moved around a square experimental apparatus while searching for a food reward at the beginning of the tasks, at which point birds had not yet fully learned the location of the food reward. Chickadees did not show a directional bias in movement at a population level. Individual variation in directional bias was significantly repeatable across years but did not significantly vary between two elevations and was not significantly associated with performance on either a spatial learning and memory task or a single spatial reversal learning task. Overall, our results show that chickadees did not show directional bias when deciding what direction to move during spatial cognitive tasks, suggesting that no consistent preference in movement direction may be advantageous when searching for food on a larger scale. Significance statement: Many animals across a wide range of taxa will consistently prefer to use either their left or right side to complete certain types of tasks. Such asymmetric behaviors may be associated with asymmetries in brain structure and are well documented in birds. Yet, mountain chickadees did not show similar directional biases in their movement-based decision-making. Furthermore, biases in their movement were not associated with overall cognitive performance. These null results suggest that while strong left or right preferences may be beneficial in certain contexts, such biases might not be advantageous while foraging for food on a larger scale. [ABSTRACT FROM AUTHOR]

Few studies have examined the stability of the representation of the position of sound sources in spatial working memory. The goal of this study was to verify whether the memory of sound position declines as maintenance time increases. In two experiments, we tested the influence of the delay between stimulus and response in a sound localization task. In Experiment 1, blindfolded participants listened to bursts of white noise originating from 16 loudspeakers equally spaced in a 360-degree circular space around the listener in such a way that the nose was aligned to the zero-degree coordinate. Their task was to indicate sounds' position using a digital pointer when prompted at varying delays: 0, 3, and 6 s after stimulus offset. In Experiment 2, the task was analogous to Exp. 1 with stimulus–response delays of 0 or 10 s. Results of the two experiments show that increasing stimulus–response delays up to 10 s do not impair sound localization. Participants systematically overestimated the eccentricity of the auditory stimulus by shifting their responses either toward the 90-degree coordinate, in alignment with the right ear, or toward the 270-degree coordinate, in alignment with the left ear. Such bias was analogous in the front and in the rear azimuthal space and was only marginally influenced by the delay conditions. We conclude that the representation of auditory space in working memory is stable, but directionally biased with systematic overestimation of eccentricity. [ABSTRACT FROM AUTHOR]

During development and disease, cells migrate collectively in response to gradients in physical, chemical and electrical cues. Despite its physiological significance and potential therapeutic applications, electrotactic collective cell movement is relatively less well understood. Here, we analyze the combined effect of intercellular interactions and electric fields on the directional migration of non-transformed mammary epithelial cells, MCF-10A. Our data show that clustered cells exhibit greater sensitivity to applied electric fields but align more slowly than isolated cells. Clustered cells achieve half-maximal directedness with an electric field that is 50% weaker than that required by isolated cells; however, clustered cells take ~2-4 fold longer to align. This trade-off in greater sensitivity and slower dynamics correlates with the slower speed and intrinsic directedness of collective movement even in the absence of an electric field. Whereas isolated cells exhibit a persistent random walk, the trajectories of clustered cells are more ballistic as evidenced by the superlinear dependence of their mean square displacement on time. Thus, intrinsically-directed, slower clustered cells take longer to redirect and align with an electric field. These findings help to define the operating space and the engineering trade-offs for using electric fields to affect cell movement in biomedical applications. [ABSTRACT FROM AUTHOR]