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https://www.readbyqxmd.com/read/28915518/-primary-care-in-germany-equal-access-for-everyone
#1
Jan Bauer, Werner Maier, Ruth Müller, David A Groneberg
Background Access to primary care plays an important role in medical care provision in Germany. Therefore, current health care planning aims at providing equal access for every patient in Germany no matter where they live. Objective This study examined accessibility of primary care and compared the result with current primary care planning data. Materials and Methods Spatial accessibility to primary care was measured by the integrated Floating Catchment Area method ("accessibility index") using a geographical information system at the level of square kilometers cells (hectare grid cells for major urban areas)...
September 15, 2017: Deutsche Medizinische Wochenschrift
https://www.readbyqxmd.com/read/28904764/the-second-southern-african-bird-atlas-project-causes-and-consequences-of-geographical-sampling-bias
#2
Sanet Hugo, Res Altwegg
Using the Southern African Bird Atlas Project (SABAP2) as a case study, we examine the possible determinants of spatial bias in volunteer sampling effort and how well such biased data represent environmental gradients across the area covered by the atlas. For each province in South Africa, we used generalized linear mixed models to determine the combination of variables that explain spatial variation in sampling effort (number of visits per 5' × 5' grid cell, or "pentad"). The explanatory variables were distance to major road and exceptional birding locations or "sampling hubs," percentage cover of protected, urban, and cultivated area, and the climate variables mean annual precipitation, winter temperatures, and summer temperatures...
September 2017: Ecology and Evolution
https://www.readbyqxmd.com/read/28890051/systemic-administration-of-two-different-anxiolytic-drugs-decreases-local-field-potential-theta-frequency-in-the-medial-entorhinal-cortex-without-affecting-grid-cell-firing-fields
#3
Caitlin K Monaghan, G William Chapman, Michael E Hasselmo
Neurons coding spatial location (grid cells) are found in medial entorhinal cortex (MEC) and demonstrate increasing size of firing fields and spacing between fields (grid scale) along the dorsoventral axis. This change in grid scale correlates with differences in theta frequency, a 6-10Hz rhythm in the local field potential (LFP) and rhythmic firing of cells. A relationship between theta frequency and grid scale can be found when examining grid cells recorded in different locations along the dorsoventral axis of MEC...
September 8, 2017: Neuroscience
https://www.readbyqxmd.com/read/28888183/periodic-population-codes-from-a-single-circular-variable-to-higher-dimensions-multiple-nested-scales-and-conceptual-spaces
#4
REVIEW
Andreas Vm Herz, Alexander Mathis, Martin Stemmler
Across the nervous system, neurons often encode circular stimuli using tuning curves that are not sine or cosine functions, but that belong to the richer class of von Mises functions, which are periodic variants of Gaussians. For a population of neurons encoding a single circular variable with such canonical tuning curves, computing a simple population vector is the optimal read-out of the most likely stimulus. We argue that the advantages of population vector read-outs are so compelling that even the neural representation of the outside world's flat Euclidean geometry is curled up into a torus (a circle times a circle), creating the hexagonal activity patterns of mammalian grid cells...
September 6, 2017: Current Opinion in Neurobiology
https://www.readbyqxmd.com/read/28876533/multi-objective-optimization-of-benzamide-derivatives-as-rho-kinase-inhibitors
#5
Giovanna Cardoso Gajo, Daniela Rodrigues Silva, Stephen J Barigye, Elaine Fontes Ferreira da Cunha
Despite recent advances in Computer Aided Drug Discovery and High Throughput Screening, the attrition rates of drug candidates continue to be high, underscoring the inherent complexity of the drug discovery paradigm. Indeed, a compromise between several objectives is often required to obtain successful clinical drugs. The present manuscript details a multi-objective workflow that integrates the 4D-QSAR and molecular docking methods in the simultaneous modeling of the Rho Kinase inhibitory activity and acute toxicity of Benzamide derivatives...
September 6, 2017: Molecular Informatics
https://www.readbyqxmd.com/read/28858613/the-aging-navigational-system
#6
REVIEW
Adam W Lester, Scott D Moffat, Jan M Wiener, Carol A Barnes, Thomas Wolbers
The discovery of neuronal systems dedicated to computing spatial information, composed of functionally distinct cell types such as place and grid cells, combined with an extensive body of human-based behavioral and neuroimaging research has provided us with a detailed understanding of the brain's navigation circuit. In this review, we discuss emerging evidence from rodents, non-human primates, and humans that demonstrates how cognitive aging affects the navigational computations supported by these systems. Critically, we show 1) that navigational deficits cannot solely be explained by general deficits in learning and memory, 2) that there is no uniform decline across different navigational computations, and 3) that navigational deficits might be sensitive markers for impending pathological decline...
August 30, 2017: Neuron
https://www.readbyqxmd.com/read/28842863/an-analysis-of-waves-underlying-grid-cell-firing-in-the-medial-enthorinal-cortex
#7
Mayte Bonilla-Quintana, Kyle C A Wedgwood, Reuben D O'Dea, Stephen Coombes
Layer II stellate cells in the medial enthorinal cortex (MEC) express hyperpolarisation-activated cyclic-nucleotide-gated (HCN) channels that allow for rebound spiking via an [Formula: see text] current in response to hyperpolarising synaptic input. A computational modelling study by Hasselmo (Philos. Trans. R. Soc. Lond. B, Biol. Sci. 369:20120523, 2013) showed that an inhibitory network of such cells can support periodic travelling waves with a period that is controlled by the dynamics of the [Formula: see text] current...
August 25, 2017: Journal of Mathematical Neuroscience
https://www.readbyqxmd.com/read/28832719/spider-species-richness-and-sampling-effort-at-cracraft%C3%A2-s-bel%C3%A3-m-area-of-endemism
#8
Bruno V B Rodrigues, Manoel B Aguiar-Neto, Ubirajara DE Oliveira, Adalberto J Santos, Antonio D Brescovit, Marlúcia B Martíns, Alexandre B Bonaldo
A list of spider species is presented for the Belém Area of Endemism, the most threatened region in the Amazon Basin, comprising portions of eastern State of Pará and western State of Maranhão, Brazil. The data are based both on records from the taxonomic and biodiversity survey literature and on scientific collection databases. A total of 319 identified species were recorded, with 318 occurring in Pará and only 22 in Maranhão. About 80% of species are recorded at the vicinities of the city of Belém, indicating that sampling effort have been strongly biased...
August 17, 2017: Anais da Academia Brasileira de Ciências
https://www.readbyqxmd.com/read/28829435/global-distribution-of-clay-size-minerals-on-land-surface-for-biogeochemical-and-climatological-studies
#9
Akihiko Ito, Rota Wagai
Clay-size minerals play important roles in terrestrial biogeochemistry and atmospheric physics, but their data have been only partially compiled at global scale. We present a global dataset of clay-size minerals in the topsoil and subsoil at different spatial resolutions. The data of soil clay and its mineralogical composition were gathered through a literature survey and aggregated by soil orders of the Soil Taxonomy for each of the ten groups: gibbsite, kaolinite, illite/mica, smectite, vermiculite, chlorite, iron oxide, quartz, non-crystalline, and others...
August 22, 2017: Scientific Data
https://www.readbyqxmd.com/read/28814638/field-repetition-and-local-mapping-in-the-hippocampus-and-medial-entorhinal-cortex
#10
Roddy M Grieves, Éléonore Duvelle, Emma R Wood, Paul Anthony Dudchenko
Hippocampal place cells support spatial cognition and are thought to form the neural substrate of a global 'cognitive map'. A widely held view is that parts of the hippocampus also underlie the ability to separate patterns, or to provide different neural codes for distinct environments. However, a number of studies have shown that in environments composed of multiple, repeating compartments, place cells and other spatially modulated neurons show the same activity in each local area. This repetition of firing fields may reflect pattern completion, and may make it difficult for animals to distinguish similar local environments...
August 16, 2017: Journal of Neurophysiology
https://www.readbyqxmd.com/read/28769779/size-matters-how-scaling-affects-the-interaction-between-grid-and-border-cells
#11
Diogo Santos-Pata, Riccardo Zucca, Sock C Low, Paul F M J Verschure
Many hippocampal cell types are characterized by a progressive increase in scale along the dorsal-to-ventral axis, such as in the cases of head-direction, grid and place cells. Also located in the medial entorhinal cortex (MEC), border cells would be expected to benefit from such scale modulations. However, this phenomenon has not been experimentally observed. Grid cells in the MEC of mammals integrate velocity related signals to map the environment with characteristic hexagonal tessellation patterns. Due to the noisy nature of these input signals, path integration processes tend to accumulate errors as animals explore the environment, leading to a loss of grid-like activity...
2017: Frontiers in Computational Neuroscience
https://www.readbyqxmd.com/read/28768062/self-organization-of-modular-activity-of-grid-cells
#12
Eugenio Urdapilleta, Bailu Si, Alessandro Treves
A unique topographical representation of space is found in the concerted activity of grid cells in the rodent medial entorhinal cortex. Many among the principal cells in this region exhibit a hexagonal firing pattern, in which each cell expresses its own set of place fields (spatial phases) at the vertices of a triangular grid, the spacing and orientation of which are typically shared with neighboring cells. Grid spacing, in particular, has been found to increase along the dorso-ventral axis of the entorhinal cortex but in discrete steps, i...
August 2, 2017: Hippocampus
https://www.readbyqxmd.com/read/28767717/disentangling-the-influence-of-environmental-and-anthropogenic-factors-on-the-distribution-of-endemic-vascular-plants-in-sardinia
#13
Mauro Fois, Giuseppe Fenu, Eva Maria Cañadas, Gianluigi Bacchetta
Due to the impelling urgency of plant conservation and the increasing availability of high resolution spatially interpolated (e.g. climate variables) and categorical data (e.g. land cover and vegetation type), many recent studies have examined relationships among plant species distributions and a diversified set of explanatory factors; nevertheless, global and regional patterns of endemic plant richness remain in many cases unexplained. One such pattern is the 294 endemic vascular plant taxa recorded on a 1 km resolution grid on the environmentally heterogeneous island of Sardinia...
2017: PloS One
https://www.readbyqxmd.com/read/28767687/a-novel-on-line-spatial-temporal-k-anonymity-method-for-location-privacy-protection-from-sequence-rules-based-inference-attacks
#14
Haitao Zhang, Chenxue Wu, Zewei Chen, Zhao Liu, Yunhong Zhu
Analyzing large-scale spatial-temporal k-anonymity datasets recorded in location-based service (LBS) application servers can benefit some LBS applications. However, such analyses can allow adversaries to make inference attacks that cannot be handled by spatial-temporal k-anonymity methods or other methods for protecting sensitive knowledge. In response to this challenge, first we defined a destination location prediction attack model based on privacy-sensitive sequence rules mined from large scale anonymity datasets...
2017: PloS One
https://www.readbyqxmd.com/read/28763654/evaluating-the-risk-of-phosphorus-loss-with-a-distributed-watershed-model-featuring-zero-order-mobilization-and-first-order-delivery
#15
Sisi Li, Liang Zhang, Hongbin Liu, Hugo A Loáiciga, Limei Zhai, Yanhua Zhuang, Qiuliang Lei, Wanli Hu, Wenchao Li, Qi Feng, Yun Du
Many semi-distributed models that simulate pollutants' losses from watersheds do not handle well detailed spatially distributed and temporal data with which to identify accurate and cost-effective strategies for controlling pollutants issuing from non-point sources. Such models commonly overlook the flow pathways of pollutants across the landscape. This work aims at closing such knowledge gap by developing a Spatially and Temporally Distributed Empirical model for Phosphorus Management (STEM-P) that simulates the daily phosphorus loss from source areas to receiving waters on a spatially-distributed grid-cell basis...
December 31, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28756950/grid-cells-encode-local-positional-information
#16
Revekka Ismakov, Omri Barak, Kate Jeffery, Dori Derdikman
The brain has an extraordinary ability to create an internal spatial map of the external world [1]. This map-like representation of environmental surroundings is encoded through specific types of neurons, located within the hippocampus and entorhinal cortex, which exhibit spatially tuned firing patterns [2, 3]. In addition to encoding space, these neurons are believed to be related to contextual information and memory [4-7]. One class of such cells is the grid cells, which are located within the entorhinal cortex, presubiculum, and parasubiculum [3, 8]...
August 7, 2017: Current Biology: CB
https://www.readbyqxmd.com/read/28750005/from-grid-cells-to-place-cells-with-realistic-field-sizes
#17
Torsten Neher, Amir Hossein Azizi, Sen Cheng
While grid cells in the medial entorhinal cortex (MEC) of rodents have multiple, regularly arranged firing fields, place cells in the cornu ammonis (CA) regions of the hippocampus mostly have single spatial firing fields. Since there are extensive projections from MEC to the CA regions, many models have suggested that a feedforward network can transform grid cell firing into robust place cell firing. However, these models generate place fields that are consistently too small compared to those recorded in experiments...
2017: PloS One
https://www.readbyqxmd.com/read/28748383/is-ambient-heat-exposure-levels-associated-with-miscarriage-or-stillbirths-in-hot-regions-a-cross-sectional-study-using-survey-data-from-the-ghana-maternal-health-survey-2007
#18
Benedict Asamoah, Tord Kjellstrom, Per-Olof Östergren
It is well established that high ambient heat could cause congenital abnormalities resulting in miscarriage or stillbirth among certain species of mammals. However, this has not been systematically studied in real field settings among humans, despite the potential value of such knowledge for estimating the impact of global warming on the human species. This study sought to test the hypothesis that maternal heat exposure during pregnancy in hot regions is associated with increased prevalence of spontaneous abortions or stillbirths and to develop an analytical strategy to use existing data from maternal health surveys and existing data on historical heat levels at a geographic grid cell level...
July 26, 2017: International Journal of Biometeorology
https://www.readbyqxmd.com/read/28731409/assessment-of-the-probability-of-autochthonous-transmission-of-chikungunya-virus-in-canada-under-recent-and-projected-climate-change
#19
Victoria Ng, Aamir Fazil, Philippe Gachon, Guillaume Deuymes, Milka Radojević, Mariola Mascarenhas, Sophiya Garasia, Michael A Johansson, Nicholas H Ogden
BACKGROUND: Chikungunya virus (CHIKV) is a reemerging pathogen transmitted by Aedes aegypti and Aedes albopictus mosquitoes. The ongoing Caribbean outbreak is of concern due to the potential for infected travelers to spread the virus to countries where vectors are present and the population is susceptible. Although there has been no autochthonous transmission of CHIKV in Canada, there is concern that both Ae. albopictus and CHIKV will become established, particularly under projected climate change...
June 5, 2017: Environmental Health Perspectives
https://www.readbyqxmd.com/read/28724433/gridsample-an-r-package-to-generate-household-survey-primary-sampling-units-psus-from-gridded-population-data
#20
Dana R Thomson, Forrest R Stevens, Nick W Ruktanonchai, Andrew J Tatem, Marcia C Castro
BACKGROUND: Household survey data are collected by governments, international organizations, and companies to prioritize policies and allocate billions of dollars. Surveys are typically selected from recent census data; however, census data are often outdated or inaccurate. This paper describes how gridded population data might instead be used as a sample frame, and introduces the R GridSample algorithm for selecting primary sampling units (PSU) for complex household surveys with gridded population data...
July 19, 2017: International Journal of Health Geographics
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