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https://www.readbyqxmd.com/read/28724433/gridsample-an-r-package-to-generate-household-survey-primary-sampling-units-psus-from-gridded-population-data
#1
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 Surveys are typically selected from recent census data; however, census data are often outdated or inaccurate.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
https://www.readbyqxmd.com/read/28708881/large-anthropogenic-impacts-on-a-charismatic-small-carnivore-insights-from-distribution-surveys-of-red-panda-ailurus-fulgens-in-nepal
#2
Saroj Panthi, Gopal Khanal, Krishna Prasad Acharya, Achyut Aryal, Arjun Srivathsa
Protected areas are key to preserving biodiversity and maintaining ecosystem services. However, their ability to ensure long-term survival of threatened andendangered species varies across countries, regions and landscapes. Distribution surveys can beparticularly important for assessing the value of protected areas, and gauging their efficacy incatering to species-specific requirements. We assessed the conservation value of one such reserve for a charismatic yet globally endangered species, the red panda Ailurus fulgens,in the light of on-going land-use transformation in Nepal...
2017: PloS One
https://www.readbyqxmd.com/read/28703324/scaling-range-sizes-to-threats-for-robust-predictions-of-risks-to-biodiversity
#3
David A Keith, H Resit Akçakaya, Nicholas J Murray
Assessments of risk to biodiversity often rely on spatial distributions of species and ecosystems. Range size metrics used extensively in these assessments, such as Area of Occupancy (AOO), are sensitive to measurement scale, prompting proposals to measure them at finer scales, or a variery of different scales based on the shape of the distribution or ecological characteristics of the biota. Despite its dominant role in Red List assessments for decades, appropriate spatial scales of AOO for predicting risks of species extinction or ecosystem collapse remain untested and contentious...
July 13, 2017: Conservation Biology: the Journal of the Society for Conservation Biology
https://www.readbyqxmd.com/read/28701481/place-and-grid-cells-in-a-loop-implications-for-memory-function-and-spatial-coding
#4
César Rennó-Costa, Adriano B L Tort
Place cells in the hippocampus and grid cells in the medial entorhinal cortex have different codes for space. However, how one code relates to the other is ill understood. Based on the anatomy of the entorhinal-hippocampal circuitry, we constructed a model of place and grid cells organized in a loop to investigate their mutual influence in the establishment of their codes for space. Using computer simulations, we first replicated experiments in rats that measured place and grid cell activity in different environments, and then assessed which features of the model account for different phenomena observed in neurophysiological data, such as pattern completion and pattern separation, global and rate remapping of place cells and realignment of grid cells...
July 12, 2017: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
https://www.readbyqxmd.com/read/28683931/filling-the-gap-using-fishers-knowledge-to-map-the-extent-and-intensity-of-fishing-activity
#5
Claire L Szostek, Lee G Murray, Ewen Bell, Michel J Kaiser
Knowledge of the extent and intensity of fishing activities is critical to inform management in relation to fishing impacts on marine conservation features. Such information can also provide insight into the potential socio-economic impacts of closures (or other restrictions) of fishing grounds that could occur through the future designation of Marine Conservation Zones (MCZs). We assessed the accuracy and validity of fishing effort data (spatial extent and relative effort) obtained from Fishers' Local Knowledge (LK) data compared to that derived from Vessel Monitoring System (VMS) data for a high-value shellfish fishery, the king scallop (Pecten maximus L...
June 20, 2017: Marine Environmental Research
https://www.readbyqxmd.com/read/28678438/examining-the-relationship-between-local-extinction-risk-and-position-in-range
#6
Elizabeth H Boakes, Nicholas J B Isaac, Richard A Fuller, Georgina M Mace, Philip J K McGowan
Over half of globally threatened animal species have experienced rapid geographic range loss. Identifying the parts of species' distributions most vulnerable to extinction would benefit conservation planning. However, previous studies give little consensus on whether ranges decline to the core or edge. Here we build on previous work by using empirical data to examine the position of recent local extinctions within species' geographic ranges, addressing range position as a continuum and exploring the influence of environmental factors...
July 5, 2017: Conservation Biology: the Journal of the Society for Conservation Biology
https://www.readbyqxmd.com/read/28675670/predicting-the-abundance-of-forest-types-across-the-eastern-u-s-through-inverse-modelling-of-tree-demography
#7
Mark C Vanderwel, Danaë M A Rozendaal, Margaret E K Evans
Global environmental change is expected to induce widespread changes in the geographic distribution and biomass of forest communities. Impacts have been projected from both empirical (statistical) and mechanistic (physiology-based) modelling approaches, but there remains an important gap in accurately predicting abundance across species' ranges from spatial variation in individual-level demographic processes. We address this issue by using a cohort-based forest dynamics model (CAIN) to predict spatial variation in the abundance of six plant functional types (PFTs) across the eastern U...
July 4, 2017: Ecological Applications: a Publication of the Ecological Society of America
https://www.readbyqxmd.com/read/28667472/erratum-to-combined-effect-of-pulse-density-and-grid-cell-size-on-predicting-and-mapping-aboveground-carbon-in-fast-growing-eucalyptus-forest-plantation-using-airborne-lidar-data
#8
Carlos Alberto Silva, Andrew Thomas Hudak, Carine Klauberg, Lee Alexandre Vierling, Carlos Gonzalez-Benecke, Samuel de Padua Chaves Carvalho, Luiz Carlos Estraviz Rodriguez, Adrián Cardil
No abstract text is available yet for this article.
December 2017: Carbon Balance and Management
https://www.readbyqxmd.com/read/28640608/numerical-diculties-computing-electrostatic-potentials-near-interfaces-with-the-poisson-boltzmann-equation
#9
Marcia Oliveira Fenley, Alexander H Boschitsch, Robert C Harris
Many researchers compute surface maps of the electrostatic potential with the Poisson-Boltzmann (PB) equation to relate the structural information obtained from X-ray and NMR experiments to biomolecular functions. Here we demonstrate that the usual method of obtaining these surface maps of electrostatic potential, by interpolating from neighboring grid points on the solution grid generated by a PB solver, generates large errors because of the large discontinuity in the dielectric constant (and thus in the normal derivative of the electrostatic potential) at the surface...
June 22, 2017: Journal of Chemical Theory and Computation
https://www.readbyqxmd.com/read/28628647/an-efficient-coding-theory-for-a-dynamic-trajectory-predicts-non-uniform-allocation-of-entorhinal-grid-cells-to-modules
#10
Noga Mosheiff, Haggai Agmon, Avraham Moriel, Yoram Burak
Grid cells in the entorhinal cortex encode the position of an animal in its environment with spatially periodic tuning curves with different periodicities. Recent experiments established that these cells are functionally organized in discrete modules with uniform grid spacing. Here we develop a theory for efficient coding of position, which takes into account the temporal statistics of the animal's motion. The theory predicts a sharp decrease of module population sizes with grid spacing, in agreement with the trend seen in the experimental data...
June 2017: PLoS Computational Biology
https://www.readbyqxmd.com/read/28628104/active-dendritic-integration-as-a-mechanism-for-robust-and-precise-grid-cell-firing
#11
Christoph Schmidt-Hieber, Gabija Toleikyte, Laurence Aitchison, Arnd Roth, Beverley A Clark, Tiago Branco, Michael Häusser
Understanding how active dendrites are exploited for behaviorally relevant computations is a fundamental challenge in neuroscience. Grid cells in medial entorhinal cortex are an attractive model system for addressing this question, as the computation they perform is clear: they convert synaptic inputs into spatially modulated, periodic firing. Whether active dendrites contribute to the generation of the dual temporal and rate codes characteristic of grid cell output is unknown. We show that dendrites of medial entorhinal cortex neurons are highly excitable and exhibit a supralinear input-output function in vitro, while in vivo recordings reveal membrane potential signatures consistent with recruitment of active dendritic conductances...
June 19, 2017: Nature Neuroscience
https://www.readbyqxmd.com/read/28599195/evaluation-of-a-data-fusion-approach-to-estimate-daily-pm2-5-levels-in-north-china
#12
Fengchao Liang, Meng Gao, Qingyang Xiao, Gregory R Carmichael, Xiaochuan Pan, Yang Liu
PM2.5 air pollution has been a growing concern worldwide. Previous studies have conducted several techniques to estimate PM2.5 exposure spatiotemporally in China, but all these have limitations. This study was to develop a data fusion approach and compare it with kriging and Chemistry Module. Two techniques were applied to create daily spatial cover of PM2.5 in grid cells with a resolution of 10km in North China in 2013, respectively, which was kriging with an external drift (KED) and Weather Research and Forecast Model with Chemistry Module (WRF-Chem)...
June 6, 2017: Environmental Research
https://www.readbyqxmd.com/read/28593558/combined-effect-of-pulse-density-and-grid-cell-size-on-predicting-and-mapping-aboveground-carbon-in-fast-growing-eucalyptus-forest-plantation-using-airborne-lidar-data
#13
Carlos Alberto Silva, Andrew Thomas Hudak, Carine Klauberg, Lee Alexandre Vierling, Carlos Gonzalez-Benecke, Samuel de Padua Chaves Carvalho, Luiz Carlos Estraviz Rodriguez, Adrián Cardil
BACKGROUND: LiDAR remote sensing is a rapidly evolving technology for quantifying a variety of forest attributes, including aboveground carbon (AGC). Pulse density influences the acquisition cost of LiDAR, and grid cell size influences AGC prediction using plot-based methods; however, little work has evaluated the effects of LiDAR pulse density and cell size for predicting and mapping AGC in fast-growing Eucalyptus forest plantations. The aim of this study was to evaluate the effect of LiDAR pulse density and grid cell size on AGC prediction accuracy at plot and stand-levels using airborne LiDAR and field data...
December 2017: Carbon Balance and Management
https://www.readbyqxmd.com/read/28593193/differential-expression-and-cell-type-specificity-of-perineuronal-nets-in-hippocampus-medial-entorhinal-cortex-and-visual-cortex-examined-in-the-rat-and-mouse
#14
Kristian Kinden Lensjø, Ane Charlotte Christensen, Simen Tennøe, Marianne Fyhn, Torkel Hafting
Perineuronal nets (PNNs) are specialized extracellular matrix (ECM) structures that condense around the soma and proximal dendrites of subpopulations of neurons. Emerging evidence suggests that they are involved in regulating brain plasticity. However, the expression of PNNs varies between and within brain areas. A lack of quantitative studies describing the distribution and cell-specificity of PNNs makes it difficult to reveal the functional roles of PNNs. In the current study, we examine the distribution of PNNs and the identity of PNN-enwrapped neurons in three brain areas with different cognitive functions: the dorsal hippocampus, medial entorhinal cortex (mEC) and primary visual cortex (V1)...
May 2017: ENeuro
https://www.readbyqxmd.com/read/28591796/histamine-enhances-theta-coupled-spiking-and-gamma-oscillations-in-the-medial-entorhinal-cortex-consistent-with-successful-spatial-recognition
#15
Quanhui Chen, Fenlan Luo, Faguo Yue, Jianxia Xia, Qin Xiao, Xiang Liao, Jun Jiang, Jun Zhang, Bo Hu, Dong Gao, Chao He, Zhian Hu
Encoding of spatial information in the superficial layers of the medial entorhinal cortex (sMEC) involves theta-modulated spiking and gamma oscillations, as well as spatially tuned grid cells and border cells. Little is known about the role of the arousal-promoting histaminergic system in the modification of information encoded in the sMEC in vivo, and how such histamine-regulated information correlates with behavioral functions. Here, we show that histamine upregulates the neural excitability of a significant proportion of neurons (16...
June 7, 2017: Cerebral Cortex
https://www.readbyqxmd.com/read/28590592/decadal-changes-in-habitat-characteristics-influence-population-trajectories-of-southern-elephant-seals
#16
Mark A Hindell, Michael Sumner, Sophie Bestley, Simon Wotherspoon, Robert G Harcourt, Mary-Anne Lea, Rachael Alderman, Clive R McMahon
Understanding divergent biological responses to climate change is important for predicting ecosystem level consequences. We use species habitat models to predict the winter foraging habitats of female southern elephant seals and investigate how changes in environmental variables within these habitats may be related to observed decreases in the Macquarie Island population. There were three main groups of seals that specialised in different ocean realms (the sub-Antarctic, the Ross Sea and the Victoria Land Coast)...
June 7, 2017: Global Change Biology
https://www.readbyqxmd.com/read/28561343/pan-arctic-sea-ice-algal-chl-a-biomass-and-suitable-habitat-are-largely-underestimated-for-multiyear-ice
#17
Benjamin A Lange, Hauke Flores, Christine Michel, Justin F Beckers, Anne Bublitz, John Alec Casey, Giulia Castellani, Ido Hatam, Anke Reppchen, Svenja A Rudolph, Christian Haas
There is mounting evidence that multiyear ice (MYI) is a unique component of the Arctic Ocean and may play a more important ecological role than previously assumed. This study improves our understanding of the potential of MYI as a suitable habitat for sea ice algae on a pan-Arctic scale. We sampled sea ice cores from MYI and first-year sea ice (FYI) within the Lincoln Sea during four consecutive spring seasons. This included four MYI hummocks with a mean chl a biomass of 2.0 mg/m(2) , a value significantly higher than FYI and MYI refrozen ponds...
May 31, 2017: Global Change Biology
https://www.readbyqxmd.com/read/28533968/changes-in-the-spatial-and-temporal-pattern-of-natural-forest-cover-on-hainan-island-from-the-1950s-to-the-2010s-implications-for-natural-forest-conservation-and-management
#18
Siliang Lin, Yaozhu Jiang, Jiekun He, Guangzhi Ma, Yang Xu, Haisheng Jiang
The study of the past, present, and future state and dynamics of the tropical natural forest cover (NFC) might help to better understand the pattern of deforestation and fragmentation as well as the influence of social and natural processes. The obtained information will support the development of effective conservation policies and strategies. In the present study, we used historical data of the road network, topography, and climatic productivity to reconstruct NFC maps of Hainan Island, China, from the 1950s to the 2010s, using the random forest algorithm...
2017: PeerJ
https://www.readbyqxmd.com/read/28515661/improving-large-area-population-mapping-using-geotweet-densities
#19
Nirav N Patel, Forrest R Stevens, Zhuojie Huang, Andrea E Gaughan, Iqbal Elyazar, Andrew J Tatem
Many different methods are used to disaggregate census data and predict population densities to construct finer scale, gridded population data sets. These methods often involve a range of high resolution geospatial covariate datasets on aspects such as urban areas, infrastructure, land cover and topography; such covariates, however, are not directly indicative of the presence of people. Here we tested the potential of geo-located tweets from the social media application, Twitter, as a covariate in the production of population maps...
April 2017: Transactions in GIS: TG
https://www.readbyqxmd.com/read/28511360/refined-2013-based-vehicle-emission-inventory-and-its-spatial-and-temporal-characteristics-in-zhengzhou-china
#20
Mimi Gong, Shasha Yin, Xingke Gu, Yuanqian Xu, Nan Jiang, Ruiqin Zhang
Vehicle emission is becoming one of the most important pollution sources because of the increase in vehicle population and activity in China. A more reasonable and complete vehicle emission inventory in Zhengzhou for the year 2013 was developed in this study. This inventory is suitable for local emission factors and vehicle kilometers of travel. Estimates show that the total carbon monoxide (CO), hydrocarbon (HC), nitrogen oxide (NOX), particulate matter (PM2.5 and PM10) and sulfur dioxide (SO2) emissions were 291Gg, 35Gg, 106Gg, 6Gg, 7Gg, and 3Gg, respectively...
December 1, 2017: Science of the Total Environment
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