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https://www.readbyqxmd.com/read/29153321/consistency-of-spatial-representations-in-rat-entorhinal-cortex-predicts-performance-in-a-reorientation-task
#1
Shahaf Weiss, Ghadeer Talhami, Xenia Gofman-Regev, Sophia Rapoport, David Eilam, Dori Derdikman
Goal-directed behavior can be affected by environmental geometry. A classic example is the rectangular arena reorientation task, where subjects commonly confuse opposite but geometrically identical corners [1]. Until recently, little was known about how environmental geometry shapes spatial representations in a neurobehavioral context [2] (although see [3]). In the present study, we asked: Under what circumstances does the internal cognitive map predict behavior? And when does it fail to do so? To this end, we developed a variant of the classical reorientation task that allows for investigation of temporal dynamics of reorientation...
November 9, 2017: Current Biology: CB
https://www.readbyqxmd.com/read/29152817/how-complex-should-models-be-comparing-correlative-and-mechanistic-range-dynamics-models
#2
Damien A Fordham, Cleo Bertelsmeier, Barry W Brook, Regan Early, Dora Neto, Stuart C Brown, Sébastien Ollier, Miguel B Araújo
Criticism has been levelled at climate-change-induced forecasts of species range shifts that do not account explicitly for complex population dynamics. The relative importance of such dynamics under climate change is, however, undetermined because direct tests comparing the performance of demographic models vs. simpler ecological niche models are still lacking owing to difficulties in evaluating forecasts using real-world data. We provide the first comparison of the skill of coupled ecological-niche-population models and ecological niche models in predicting documented shifts in the ranges of 20 British breeding bird species across a 40-year period...
November 20, 2017: Global Change Biology
https://www.readbyqxmd.com/read/29151838/observation-and-model-based-estimates-of-particulate-dry-nitrogen-deposition-to-the-oceans
#3
Alex R Baker, Maria Kanakidou, Katye E Altieri, Nikos Daskalakis, Gregory S Okin, Stelios Myriokefalitakis, Frank Dentener, Mitsuo Uematsu, Manmohan M Sarin, Robert A Duce, James N Galloway, William C Keene, Arvind Singh, Lauren Zamora, Jean-Francois Lamarque, Shih-Chieh Hsu, Shital S Rohekar, Joseph M Prospero
Anthropogenic nitrogen (N) emissions to the atmosphere have increased significantly the deposition of nitrate (NO3(-)) and ammonium (NH4(+)) to the surface waters of the open ocean, with potential impacts on marine productivity and the global carbon cycle. Global-scale understanding of the impacts of N deposition to the oceans is reliant on our ability to produce and validate models of nitrogen emission, atmospheric chemistry, transport and deposition. In this work, ~2900 observations of aerosol NO3(-) and NH4(+) concentrations, acquired from sampling aboard ships in the period 1995 - 2012, are used to assess the performance of modelled N concentration and deposition fields over the remote ocean...
2017: Atmospheric Chemistry and Physics
https://www.readbyqxmd.com/read/29140639/determining-the-effectiveness-of-mirrors-and-camera-systems-in-monitoring-the-rearward-visibility-of-self-propelled-agricultural-machinery
#4
Shawn G Ehlers, William E Field
This study concerned the ability of operators of tractors and other self-propelled agricultural machinery to visually recognize objects and/or hazards within close proximity to the rear of those machines and/or any implements in tow, especially when backing up. It was hypothesized that the data collected would identify the factors affecting rearward visibility and help determine the effectiveness of two backup-assisting devices (i.e., mirrors and camera systems) in enhancing the operator's ability to observe objects or hazards...
July 31, 2017: Journal of Agricultural Safety and Health
https://www.readbyqxmd.com/read/29138494/drying-in-a-microfluidic-chip-experiments-and-simulations
#5
Paolo Fantinel, Oshri Borgman, Ran Holtzman, Lucas Goehring
We present an experimental micro-model of drying porous media, based on microfluidic cells made of arrays of pillars on a regular grid, and complement these experiments with a matching two-dimensional pore-network model of drying. Disorder, or small-scale heterogeneity, was introduced into the cells by randomly varying the radii of the pillars. The microfluidic chips were filled with a volatile oil and then dried horizontally, such that gravitational effects were excluded. The experimental and simulated drying rates and patterns were then compared in detail, for various levels of disorder...
November 14, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29134013/southern-ocean-echinoids-database-an-updated-version-of-antarctic-sub-antarctic-and-cold-temperate-echinoid-database
#6
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/29120171/environmental-impacts-of-future-urban-deployment-of-electric-vehicles-assessment-framework-and-case-study-of-copenhagen-for-2016-2030
#7
Florence Alexia Bohnes, Jay Sterling Gregg, Alexis Laurent
To move towards environmentally-sustainable transport systems, electric vehicles (EVs) are increasingly seen as viable alternatives to internal combustion vehicles (ICVs). To ensure effectiveness of such deployment, holistic assessments of environmental impacts can help decision-makers determine optimised urban strategies in a long-term perspective. However, explicit guidance and conduct of such assessments are currently missing. Here, we therefore propose a framework using life cycle assessment that enables the quantification of environmental impacts of a transport system at full urban scale from a fleet-based, foresight perspective...
November 9, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/29115737/reinterpreting-dermoscopic-pigment-network-with-reflectance-confocal-microscopy-for-identification-of-melanoma-specific-features
#8
B De Pace, F Farnetani, A Losi, S Ciardo, N De Carvalho, Anna M Cesinaro, L Reggiani Bonetti, J Chester, S Kaleci, E Del Duca, Steven P Nisticò, C Longo, G Pellacani
BACKGROUND: Pigment network is an important dermoscopic features for melanocytic lesions but alterations in grid line thickness are also observed in melanomas. OBJECTIVE: To investigate features of thick, thin and mixed pigment networks at dermoscopy and their respective features at Reflectance Confocal Microscopy (RCM) for differential diagnosis, correlated with histology METHODS: All melanocytic lesions with histological diagnosis, evaluated between January 2010 - May 2014, were enrolled and classified according to dermoscopy evaluation of the pigment network; thin, thick and mixed...
November 8, 2017: Journal of the European Academy of Dermatology and Venereology: JEADV
https://www.readbyqxmd.com/read/29111257/a-catchment-scale-model-to-predict-spatial-and-temporal-burden-of-e-coli-on-pasture-from-grazing-livestock
#9
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
#10
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
#11
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/29083312/bioprinted-chitosan-gelatin-thermosensitive-hydrogels-using-an-inexpensive-3d-printer
#12
Kevin D Roehm, Sundararajan V Madihally
The primary bottleneck in bioprinting cell-laden structures with carefully controlled spatial relation is a lack of biocompatible inks and printing conditions. In this regard, we explored using thermogelling chitosan-gelatin (CG) hydrogel as a novel bioprinting ink; CG hydrogels is unique in that it undergoes a spontaneous phase change at physiological temperature, and does not need post-processing. In addition, we used a low cost (<$800) compact 3D printer, and modified with a new extruder to print using disposable syringes and hypodermic needles...
October 30, 2017: Biofabrication
https://www.readbyqxmd.com/read/29078993/distinguishing-signal-from-autofluorescence-in-cryogenic-correlated-light-and-electron-microscopy-of-mammalian-cells
#13
Stephen D Carter, Shrawan K Mageswaran, Zachary J Farino, João I Mamede, Catherine M Oikonomou, Thomas J Hope, Zachary Freyberg, Grant J Jensen
In cryogenic correlated light and electron microscopy (cryo-CLEM), frozen targets of interest are identified and located on EM grids by fluorescence microscopy and then imaged at higher resolution by cryo-EM. Whilst working with these methods, we discovered that a variety of mammalian cells exhibit strong punctate autofluorescence when imaged under cryogenic conditions (80 K). Autofluorescence originated from multilamellar bodies (MLBs) and secretory granules. Here we describe a method to distinguish fluorescent protein tags from these autofluorescent sources based on the narrower emission spectrum of the former...
October 25, 2017: Journal of Structural Biology
https://www.readbyqxmd.com/read/29075993/grid-mapping-a-novel-method-of-signal-quality-evaluation-on-a-single-lead-electrocardiogram
#14
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/29073650/the-cognitive-map-in-humans-spatial-navigation-and-beyond
#15
REVIEW
Russell A Epstein, Eva Zita Patai, Joshua B Julian, Hugo J Spiers
The 'cognitive map' hypothesis proposes that brain builds a unified representation of the spatial environment to support memory and guide future action. Forty years of electrophysiological research in rodents suggest that cognitive maps are neurally instantiated by place, grid, border and head direction cells in the hippocampal formation and related structures. Here we review recent work that suggests a similar functional organization in the human brain and yields insights into how cognitive maps are used during spatial navigation...
October 26, 2017: Nature Neuroscience
https://www.readbyqxmd.com/read/29073644/spatial-representation-in-the-hippocampal-formation-a-history
#16
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/29068193/biomimetic-inks-based-on-cellulose-nanofibrils-and-cross-linkable-xylans-for-3d-printing
#17
Kajsa Markstedt, Alfredo Escalante, Guillermo Toriz, Paul Gatenholm
This paper presents a sustainable all-wood-based ink which can be used for 3D printing of constructs for a large variety of applications such as clothes, furniture, electronics, and health care products with a customized design and versatile gel properties. The 3D printing technologies where the material is dispensed in the form of liquids, so called inks, have proven suitable for 3D printing dispersions of cellulose nanofibrils (CNFs) because of their unique shear thinning properties. In this study, novel inks were developed with a biomimetic approach where the structural properties of cellulose and the cross-linking function of hemicelluloses that are found in the plant cell wall were utilized...
November 7, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/29063095/one-step-fabrication-of-mesh-reinforced-hierarchic-perforated-microporous-honeycomb-films-with-tunable-filtering-property
#18
Jun Kamei, Hiroshi Yabu
Highly ordered porous films whose pore size ranges from submicron to micron scale have always been an extensive area of research due to their broad range of application to photonic crystals, cell culturing scaffolds, filtration and separation membranes, just to name a few. However, the fragile nature of such a functional porous film has hindered its implementation to advanced uses. Inspired by the hierarchic structure in nature which offers both robustness and functionality, we created in a single fabrication step a mesh-reinforced hierarchic perforated honeycomb film with highly ordered micron pores using the breath figure method...
November 8, 2017: Soft Matter
https://www.readbyqxmd.com/read/29060564/detecting-impaired-vision-caused-by-amd-from-gaze-data
#19
Huiying Liu, Yanwu Xu, Damon Wong, Ai Ping Yow, Augustinus Laude, Tock Han Lim
Age Related Macular Degeneration (AMD) is the third leading cause of blindness and the first one in the elderly. AMD usually causes central blindness due to loss of photoreceptor cell . In this paper, we propose to detect AMD caused vision impairment from gaze data. Compared with the current methods, e.g., Amsler grid, Microperimetry and Preferential Hyperacuity Perimetry, to detect vision impairments, the proposed method has several advantages. 1) It does not require the patient to stare at a fixed position throughout the test...
July 2017: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/29056296/task-demands-predict-a-dynamic-switch-in-the-content-of-awake-hippocampal-replay
#20
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
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