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https://www.readbyqxmd.com/read/29134013/southern-ocean-echinoids-database-an-updated-version-of-antarctic-sub-antarctic-and-cold-temperate-echinoid-database
#1
Salomé Fabri-Ruiz, Thomas Saucède, Bruno Danis, Bruno David
This database includes over 7,100 georeferenced occurrence records of sea urchins (Echinodermata: Echinoidea) obtained from samples collected in the Southern Ocean (+180°W/+180°E; -35°/-78°S) during oceanographic cruises led over 150 years, from 1872 to 2015. Echinoids are common organisms of Southern Ocean benthic communities. A total of 201 species is recorded, which display contrasting depth ranges and distribution patterns across austral provinces and bioregions. Echinoid species show various ecological traits including different nutrition and reproductive strategies...
2017: ZooKeys
https://www.readbyqxmd.com/read/29111257/a-catchment-scale-model-to-predict-spatial-and-temporal-burden-of-e-coli-on-pasture-from-grazing-livestock
#2
David M Oliver, Phil J Bartie, A Louise Heathwaite, Sim M Reaney, Jared A Q Parnell, Richard S Quilliam
Effective management of diffuse microbial water pollution from agriculture requires a fundamental understanding of how spatial patterns of microbial pollutants, e.g. E. coli, vary over time at the landscape scale. The aim of this study was to apply the Visualising Pathogen &Environmental Risk (ViPER) model, developed to predict E. coli burden on agricultural land, in a spatially distributed manner to two contrasting catchments in order to map and understand changes in E. coli burden contributed to land from grazing livestock...
October 27, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/29109512/modulating-medial-septal-cholinergic-activity-reduces-medial-entorhinal-theta-frequency-without-affecting-speed-or-grid-coding
#3
Francis Carpenter, Neil Burgess, Caswell Barry
Medial septal inputs to the hippocampal system are crucial for aspects of temporal and spatial processing, such as theta oscillations and grid cell firing. However, the precise contributions of the medial septum's cholinergic neurones to these functions remain unknown. Here, we recorded neuronal firing and local field potentials from the medial entorhinal cortex of freely foraging mice, while modulating the excitability of medial septal cholinergic neurones. Alteration of cholinergic activity produced a reduction in the frequency of theta oscillations, without affecting the slope of the non-linear theta frequency vs running speed relationship observed...
November 6, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29097084/exposure-to-fine-particulate-matter-during-pregnancy-and-risk-of-term-low-birth-weight-in-jinan-china-2014-2016
#4
Han Wu, Baofa Jiang, Xingyi Geng, Ping Zhu, Zhong Liu, Liangliang Cui, Liping Yang
BACKGROUND: Existing studies exploring the association between low birth weight (LBW) and maternal fine particulate matter (aerodynamic diameter<2.5μm, PM2.5) exposure have presented equivocal results, and one of the possible reasons for this finding might be due to relatively low maternal exposures. In addition, relatively narrow maternal exposure windows to PM2.5 have not been well established for LBW. METHODS: We employed a nested matched case-control design among 43,855 term births in a large maternity and child care hospital in Jinan, China...
October 28, 2017: International Journal of Hygiene and Environmental Health
https://www.readbyqxmd.com/read/29075993/grid-mapping-a-novel-method-of-signal-quality-evaluation-on-a-single-lead-electrocardiogram
#5
Yanjun Li, Xiaoying Tang
Diagnosis of long-term electrocardiogram (ECG) calls for automatic and accurate methods of ECG signal quality estimation, not only to lighten the burden of the doctors but also to avoid misdiagnoses. In this paper, a novel waveform-based method of phase-space reconstruction for signal quality estimation on a single lead ECG was proposed by projecting the amplitude of the ECG and its first order difference into grid cells. The waveform of a single lead ECG was divided into non-overlapping episodes (Ts = 10, 20, 30 s), and the number of grids in both the width and the height of each map are in the range [20, 100] (NX = NY = 20, 30, 40, … 90, 100)...
October 26, 2017: Australasian Physical & Engineering Sciences in Medicine
https://www.readbyqxmd.com/read/29073644/spatial-representation-in-the-hippocampal-formation-a-history
#6
REVIEW
Edvard I Moser, May-Britt Moser, Bruce L McNaughton
Since the first place cell was recorded and the cognitive-map theory was subsequently formulated, investigation of spatial representation in the hippocampal formation has evolved in stages. Early studies sought to verify the spatial nature of place cell activity and determine its sensory origin. A new epoch started with the discovery of head direction cells and the realization of the importance of angular and linear movement-integration in generating spatial maps. A third epoch began when investigators turned their attention to the entorhinal cortex, which led to the discovery of grid cells and border cells...
October 26, 2017: Nature Neuroscience
https://www.readbyqxmd.com/read/29056296/task-demands-predict-a-dynamic-switch-in-the-content-of-awake-hippocampal-replay
#7
H Freyja Ólafsdóttir, Francis Carpenter, Caswell Barry
Reactivation of hippocampal place cell sequences during behavioral immobility and rest has been linked with both memory consolidation and navigational planning. Yet it remains to be investigated whether these functions are temporally segregated, occurring during different behavioral states. During a self-paced spatial task, awake hippocampal replay occurring either immediately before movement toward a reward location or just after arrival at a reward location preferentially involved cells consistent with the current trajectory...
November 15, 2017: Neuron
https://www.readbyqxmd.com/read/29037492/modelling-daily-pm2-5-concentrations-at-high-spatio-temporal-resolution-across-switzerland
#8
Kees de Hoogh, Harris Héritier, Massimo Stafoggia, Nino Künzli, Itai Kloog
Spatiotemporal resolved models were developed predicting daily fine particulate matter (PM2.5) concentrations across Switzerland from 2003 to 2013. Relatively sparse PM2.5 monitoring data was supplemented by imputing PM2.5 concentrations at PM10 sites, using PM2.5/PM10 ratios at co-located sites. Daily PM2.5 concentrations were first estimated at a 1 × 1km resolution across Switzerland, using Multiangle Implementation of Atmospheric Correction (MAIAC) spectral aerosol optical depth (AOD) data in combination with spatiotemporal predictor data in a four stage approach...
October 13, 2017: Environmental Pollution
https://www.readbyqxmd.com/read/28988095/assessing-the-resilience-of-urban-areas-to-traffic-related-air-pollution-application-in-greater-paris
#9
Jean-Marie Cariolet, Morgane Colombert, Marc Vuillet, Youssef Diab
Recent studies report that outdoor air pollution will become the main environmental cause of premature death over the next few decades (OECD, 2012; WHO, 2014; World Bank, 2016). Cities are considered hot spots and urban populations are particularly exposed. There is therefore an urgent need to adapt urban systems and urban design to tackle this issue. While most European cities have introduced measures to reduce emissions, action is still required to reduce concentrations and exposure, and a holistic approach to urban design is badly needed...
February 15, 2018: Science of the Total Environment
https://www.readbyqxmd.com/read/28968386/a-single-cell-spiking-model-for-the-origin-of-grid-cell-patterns
#10
Tiziano D'Albis, Richard Kempter
Spatial cognition in mammals is thought to rely on the activity of grid cells in the entorhinal cortex, yet the fundamental principles underlying the origin of grid-cell firing are still debated. Grid-like patterns could emerge via Hebbian learning and neuronal adaptation, but current computational models remained too abstract to allow direct confrontation with experimental data. Here, we propose a single-cell spiking model that generates grid firing fields via spike-rate adaptation and spike-timing dependent plasticity...
October 2017: PLoS Computational Biology
https://www.readbyqxmd.com/read/28967910/the-hippocampus-as-a-predictive-map
#11
Kimberly L Stachenfeld, Matthew M Botvinick, Samuel J Gershman
A cognitive map has long been the dominant metaphor for hippocampal function, embracing the idea that place cells encode a geometric representation of space. However, evidence for predictive coding, reward sensitivity and policy dependence in place cells suggests that the representation is not purely spatial. We approach this puzzle from a reinforcement learning perspective: what kind of spatial representation is most useful for maximizing future reward? We show that the answer takes the form of a predictive representation...
November 2017: Nature Neuroscience
https://www.readbyqxmd.com/read/28965758/parvalbumin-and-somatostatin-interneurons-control-different-space-coding-networks-in-the-medial-entorhinal-cortex
#12
Chenglin Miao, Qichen Cao, May-Britt Moser, Edvard I Moser
The medial entorhinal cortex (MEC) contains several discrete classes of GABAergic interneurons, but their specific contributions to spatial pattern formation in this area remain elusive. We employed a pharmacogenetic approach to silence either parvalbumin (PV)- or somatostatin (SOM)-expressing interneurons while MEC cells were recorded in freely moving mice. PV-cell silencing antagonized the hexagonally patterned spatial selectivity of grid cells, especially in layer II of MEC. The impairment was accompanied by reduced speed modulation in colocalized speed cells...
October 19, 2017: Cell
https://www.readbyqxmd.com/read/28958464/mapping-under-5-and-neonatal-mortality-in-africa-2000-15-a-baseline-analysis-for-the-sustainable-development-goals
#13
Nick Golding, Roy Burstein, Joshua Longbottom, Annie J Browne, Nancy Fullman, Aaron Osgood-Zimmerman, Lucas Earl, Samir Bhatt, Ewan Cameron, Daniel C Casey, Laura Dwyer-Lindgren, Tamer H Farag, Abraham D Flaxman, Maya S Fraser, Peter W Gething, Harry S Gibson, Nicholas Graetz, L Kendall Krause, Xie Rachel Kulikoff, Stephen S Lim, Bonnie Mappin, Chloe Morozoff, Robert C Reiner, Amber Sligar, David L Smith, Haidong Wang, Daniel J Weiss, Christopher J L Murray, Catherine L Moyes, Simon I Hay
BACKGROUND: During the Millennium Development Goal (MDG) era, many countries in Africa achieved marked reductions in under-5 and neonatal mortality. Yet the pace of progress toward these goals substantially varied at the national level, demonstrating an essential need for tracking even more local trends in child mortality. With the adoption of the Sustainable Development Goals (SDGs) in 2015, which established ambitious targets for improving child survival by 2030, optimal intervention planning and targeting will require understanding of trends and rates of progress at a higher spatial resolution...
September 25, 2017: Lancet
https://www.readbyqxmd.com/read/28915518/-primary-care-in-germany-equal-access-for-everyone
#14
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
#15
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
#16
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...
November 19, 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
#17
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...
October 2017: Current Opinion in Neurobiology
https://www.readbyqxmd.com/read/28876533/multi-objective-optimization-of-benzamide-derivatives-as-rho-kinase-inhibitors
#18
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
#19
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
#20
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
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