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https://www.readbyqxmd.com/read/29218403/the-storage-and-recall-of-memories-in-the-hippocampo-cortical-system
#1
REVIEW
Edmund T Rolls
A quantitative computational theory of the operation of the hippocampus as an episodic memory system is described. The CA3 system operates as a single attractor or autoassociation network (1) to enable rapid one-trial associations between any spatial location (place in rodents or spatial view in primates) and an object or reward and (2) to provide for completion of the whole memory during recall from any part. The theory is extended to associations between time and object or reward to implement temporal order memory, which is also important in episodic memory...
December 7, 2017: Cell and Tissue Research
https://www.readbyqxmd.com/read/29217989/bayesian-inference-of-metal-oxide-ultrathin-film-structure-based-on-crystal-truncation-rod-measurements
#2
Masato Anada, Yoshinori Nakanishi-Ohno, Masato Okada, Tsuyoshi Kimura, Yusuke Wakabayashi
Monte Carlo (MC)-based refinement software to analyze the atomic arrangements of perovskite oxide ultrathin films from the crystal truncation rod intensity is developed on the basis of Bayesian inference. The advantages of the MC approach are (i) it is applicable to multi-domain structures, (ii) it provides the posterior probability of structures through Bayes' theorem, which allows one to evaluate the uncertainty of estimated structural parameters, and (iii) one can involve any information provided by other experiments and theories...
December 1, 2017: Journal of Applied Crystallography
https://www.readbyqxmd.com/read/29216467/drivers-of-dissolved-organic-carbon-export-in-a-subarctic-catchment-importance-of-microbial-decomposition-sorption-desorption-peatland-and-lateral-flow
#3
Jing Tang, Alla Y Yurova, Guy Schurgers, Paul A Miller, Stefan Olin, Benjamin Smith, Matthias B Siewert, David Olefeldt, Petter Pilesjö, Anneli Poska
Tundra soils account for 50% of global stocks of soil organic carbon (SOC), and it is expected that the amplified climate warming in high latitude could cause loss of this SOC through decomposition. Decomposed SOC could become hydrologically accessible, which increase downstream dissolved organic carbon (DOC) export and subsequent carbon release to the atmosphere, constituting a positive feedback to climate warming. However, DOC export is often neglected in ecosystem models. In this paper, we incorporate processes related to DOC production, mineralization, diffusion, sorption-desorption, and leaching into a customized arctic version of the dynamic ecosystem model LPJ-GUESS in order to mechanistically model catchment DOC export, and to link this flux to other ecosystem processes...
December 4, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/29213234/cognitive-mapping-based-on-conjunctive-representations-of-space-and-movement
#4
Taiping Zeng, Bailu Si
It is a challenge to build robust simultaneous localization and mapping (SLAM) system in dynamical large-scale environments. Inspired by recent findings in the entorhinal-hippocampal neuronal circuits, we propose a cognitive mapping model that includes continuous attractor networks of head-direction cells and conjunctive grid cells to integrate velocity information by conjunctive encodings of space and movement. Visual inputs from the local view cells in the model provide feedback cues to correct drifting errors of the attractors caused by the noisy velocity inputs...
2017: Frontiers in Neurorobotics
https://www.readbyqxmd.com/read/29209817/analysis-of-road-development-and-associated-agricultural-land-use-change
#5
Hakan Alphan
Development of road network is one of the strongest drivers of habitat fragmentation. It interferes with ecological processes that are based on material and energy flows between landscape patches. Therefore, changes in temporal patterns of roads may be regarded as important landscape-level environmental indicators. The aim of this study is to analyze road development and associated agricultural land use change near the town of Erdemli located in the eastern Mediterranean coast of Turkey. The study area has witnessed an unprecedented development of agriculture since the 2000s...
December 5, 2017: Environmental Monitoring and Assessment
https://www.readbyqxmd.com/read/29196525/mapping-local-and-global-variability-in-plant-trait-distributions
#6
Ethan E Butler, Abhirup Datta, Habacuc Flores-Moreno, Ming Chen, Kirk R Wythers, Farideh Fazayeli, Arindam Banerjee, Owen K Atkin, Jens Kattge, Bernard Amiaud, Benjamin Blonder, Gerhard Boenisch, Ben Bond-Lamberty, Kerry A Brown, Chaeho Byun, Giandiego Campetella, Bruno E L Cerabolini, Johannes H C Cornelissen, Joseph M Craine, Dylan Craven, Franciska T de Vries, Sandra Díaz, Tomas F Domingues, Estelle Forey, Andrés González-Melo, Nicolas Gross, Wenxuan Han, Wesley N Hattingh, Thomas Hickler, Steven Jansen, Koen Kramer, Nathan J B Kraft, Hiroko Kurokawa, Daniel C Laughlin, Patrick Meir, Vanessa Minden, Ülo Niinemets, Yusuke Onoda, Josep Peñuelas, Quentin Read, Lawren Sack, Brandon Schamp, Nadejda A Soudzilovskaia, Marko J Spasojevic, Enio Sosinski, Peter E Thornton, Fernando Valladares, Peter M van Bodegom, Mathew Williams, Christian Wirth, Peter B Reich
Our ability to understand and predict the response of ecosystems to a changing environment depends on quantifying vegetation functional diversity. However, representing this diversity at the global scale is challenging. Typically, in Earth system models, characterization of plant diversity has been limited to grouping related species into plant functional types (PFTs), with all trait variation in a PFT collapsed into a single mean value that is applied globally. Using the largest global plant trait database and state of the art Bayesian modeling, we created fine-grained global maps of plant trait distributions that can be applied to Earth system models...
December 1, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/29192554/prognostic-significance-of-ki67-and-its-correlation-with-mitotic-index-in-dogs-with-diffuse-large-b-cell-lymphoma-treated-with-19-week-chop-based-protocol
#7
Oscar R Sierra Matiz, Juliana Santilli, Leticia A Anai, Maria C L Da Silva, Felipe A Sueiro, Júlio L Sequeira, Larissa F Magalhães, Geórgia M Magalhães, Mirela Tinucci Costa, Sabryna G Calazans
Diffuse large B-cell lymphoma (DLBCL) is the most common type of lymphoma in dogs. We evaluated Ki67 immunoexpression and mitotic index (MI) in dogs diagnosed with DLBCL and treated with a 19-wk CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) protocol. Twenty-nine lymph node samples from dogs diagnosed with DLBCL were analyzed for Ki67 immunostaining, and positive cells present in 1 cm2 were counted in a grid reticle for comparison of survival times above and below the means. The Ki67 mean was 107, and the MI mean was 21...
November 1, 2017: Journal of Veterinary Diagnostic Investigation
https://www.readbyqxmd.com/read/29190508/evaluation-of-sediment-and-137cs-redistribution-in-the-oginosawa-river-catchment-near-the-fukushima-dai-ichi-nuclear-power-plant-using-integrated-watershed-modeling
#8
Kazuyuki Sakuma, Alex Malins, Hironori Funaki, Hiroshi Kurikami, Tadafumi Niizato, Takahiro Nakanishi, Koji Mori, Kazuhiro Tada, Takamaru Kobayashi, Akihiro Kitamura, Masaaki Hosomi
The Oginosawa River catchment lies 15 km south-west of the Fukushima Dai-ichi nuclear plant and covers 7.7 km2. Parts of the catchment were decontaminated between fall 2012 and March 2014 in preparation for the return of the evacuated population. The General-purpose Terrestrial Fluid-flow Simulator (GETFLOWS) code was used to study sediment and 137Cs redistribution within the catchment, including the effect of decontamination on redistribution. Fine resolution grid cells were used to model local features of the catchment, such as paddy fields adjacent to the Oginosawa River...
November 27, 2017: Journal of Environmental Radioactivity
https://www.readbyqxmd.com/read/29176562/understanding-heat-patterns-produced-by-vehicular-flows-in-urban-areas
#9
Rui Zhu, Man Sing Wong, Éric Guilbert, Pak-Wai Chan
Vehicular traffic has strong implication in the severity and degree of Urban Heat Island (UHI) effect in a city. It is crucial to map and monitor the spatio-temporal heat patterns from vehicular traffic in a city. Data observed from traffic counting stations are readily available for mapping the traffic-related heat across the stations. However, macroscopic models utilizing traffic counting data to estimate dynamic directional vehicular flows are rarely established. Our work proposes a simple and robust cell-transmission-model to simulate all the possible cell-based origin-destination trajectories of vehicular flows over time, based on the traffic counting stations...
November 24, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29170377/transformation-of-the-head-direction-signal-into-a-spatial-code
#10
Adrien Peyrache, Natalie Schieferstein, Gyorgy Buzsáki
Animals integrate multiple sensory inputs to successfully navigate in their environments. Head direction (HD), boundary vector, grid and place cells in the entorhinal-hippocampal network form the brain's navigational system that allows to identify the animal's current location, but how the functions of these specialized neuron types are acquired remain to be understood. Here we report that activity of HD neurons is influenced by the ambulatory constraints imposed upon the animal by the boundaries of the explored environment, leading to spurious spatial information...
November 24, 2017: Nature Communications
https://www.readbyqxmd.com/read/29170352/55%C3%A2-mini-sim-innovative-bite-sized-simulation-teaching-in-a-busy-children-s-emergency-department
#11
Rachel Sunley, Karen Moloney, Jessica Parker, Christopher Arrowsmith, Kirsty Brown, Alex Wilson
: Emergency Medicine requires a highly skilled workforce who are passionate about delivering excellent patient care. Shift patterns linked with the ever increasing numbers of patients who attend Emergency Departments puts strain on educating the workforce and fostering team togetherness.Our objective in devising and instigating the 'Mini Sim' programme was to embed regular in-situ simulation training to enhance the learning of all staff within our Emergency Department team, building a highly trained workforce to deliver excellent care within the remit of our busy department...
December 2017: Emergency Medicine Journal: EMJ
https://www.readbyqxmd.com/read/29168876/a-compartmentalized-microfluidic-chip-with-crisscross-microgrooves-and-electrophysiological-electrodes-for-modeling-the-blood-retinal-barrier
#12
Jose Yeste, Marta García-Ramírez, Xavi Illa, Anton Guimerà, Cristina Hernández, Rafael Simó, Rosa Villa
The interconnection of different tissue-tissue interfaces may extend organ-on-chips to a new generation of sophisticated models capable of recapitulating more complex organ-level functions. Single interfaces are largely recreated in organ-on-chips by culturing the cells on opposite sides of a porous membrane that splits a chamber in two or by connecting the cells of two adjacent compartments through microchannels. However, it is difficult to interconnect more than one interface using these approaches. To address this challenge, we present a novel microfluidic device where cells are arranged in parallel compartments and are highly interconnected through a grid of microgrooves, which facilitates paracrine signaling and heterotypic cell-cell contact between multiple tissues...
November 23, 2017: Lab on a Chip
https://www.readbyqxmd.com/read/29153321/consistency-of-spatial-representations-in-rat-entorhinal-cortex-predicts-performance-in-a-reorientation-task
#13
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
#14
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
#15
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
#16
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
#17
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
#18
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
#19
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
#20
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
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