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https://www.readbyqxmd.com/read/28532055/gold-nanoparticles-prevent-cognitive-deficits-oxidative-stress-and-inflammation-in-a-rat-model-of-sporadic-dementia-of-alzheimer-s-type
#1
Alexandre Pastoris Muller, Gabriela K Ferreira, Allison José Pires, Gustavo de Bem Silveira, Débora Laureano de Souza, Joice de Abreu Brandolfi, Claudio Teodoro de Souza, Marcos M S Paula, Paulo Cesar Lock Silveira
Alzheimer's disease (AD) is the most common form of neurodegenerative dementia in the aged brain. Even though its etiology is unknown, factors such as neuroinflammation, mitochondrial dysfunction, formation of reactive oxygen species (ROS), and impaired insulin signaling may play a role. We used a sporadic AD model in rats generated by intracerebroventricular-streptozotocin (i.c.v.-STZ) injection to test the therapeutic effect of gold nanoparticles (GNPs). We tested the null hypothesis that there would be no difference between the STZ+GNPs group and the STZ group in the analyzed markers...
August 1, 2017: Materials Science & Engineering. C, Materials for Biological Applications
https://www.readbyqxmd.com/read/28531962/how-geostatistics-can-help-you-find-lead-and-galvanized-water-service-lines-the-case-of-flint-mi
#2
Pierre Goovaerts
In the aftermath of Flint drinking water crisis, most US cities have been scrambling to locate all lead service lines (LSLs) in their water supply systems. This information, which is most often inaccurate or lacking, is critical to assess compliance with the Lead and Copper Rule and to plan the replacement of lead and galvanized service lines (GSLs) as currently under way in Flint. This paper presents the first geospatial approach to predict the likelihood that a home has a LSL or GSL based on neighboring field data (i...
May 17, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28531949/wastewater-discharge-impact-on-drinking-water-sources-along-the-yangtze-river-china
#3
Zhuomin Wang, Dongguo Shao, Paul Westerhoff
Unplanned indirect (de facto) wastewater reuse occurs when wastewater is discharged into surface waters upstream of potable drinking water treatment plant intakes. This paper aims to predict percentages and trends of de facto reuse throughout the Yangtze River watershed in order to understand the relative contribution of wastewater discharges into the river and its tributaries towards averting water scarcity concerns. The Yangtze River is the third longest in the world and supports more than 1/15 of the world's population, yet the importance of wastewater on the river remains ill-defined...
May 17, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28531796/spatially-explicit-modeling-of-multi-scale-drivers-of-aboveground-forest-biomass-and-water-yield-in-watersheds-of-the-southeastern-united-states
#4
Mukhtar Ahmed Ajaz Ahmed, Amr Abd-Elrahman, Francisco J Escobedo, Wendell P Cropper, Timothy A Martin, Nilesh Timilsina
Understanding ecosystem processes and the influence of regional scale drivers can provide useful information for managing forest ecosystems. Examining more local scale drivers of forest biomass and water yield can also provide insights for identifying and better understanding the effects of climate change and management on forests. We used diverse multi-scale datasets, functional models and Geographically Weighted Regression (GWR) to model ecosystem processes at the watershed scale and to interpret the influence of ecological drivers across the Southeastern United States (SE US)...
May 19, 2017: Journal of Environmental Management
https://www.readbyqxmd.com/read/28531202/the-role-of-density-dependent-and-independent-processes-in-spawning-habitat-selection-by-salmon-in-an-arctic-riverscape
#5
Brock M Huntsman, Jeffrey A Falke, James W Savereide, Katrina E Bennett
Density-dependent (DD) and density-independent (DI) habitat selection is strongly linked to a species' evolutionary history. Determining the relative importance of each is necessary because declining populations are not always the result of altered DI mechanisms but can often be the result of DD via a reduced carrying capacity. We developed spatially and temporally explicit models throughout the Chena River, Alaska to predict important DI mechanisms that influence Chinook salmon spawning success. We used resource-selection functions to predict suitable spawning habitat based on geomorphic characteristics, a semi-distributed water-and-energy balance hydrologic model to generate stream flow metrics, and modeled stream temperature as a function of climatic variables...
2017: PloS One
https://www.readbyqxmd.com/read/28531184/bacarena-individual-based-metabolic-modeling-of-heterogeneous-microbes-in-complex-communities
#6
Eugen Bauer, Johannes Zimmermann, Federico Baldini, Ines Thiele, Christoph Kaleta
Recent advances focusing on the metabolic interactions within and between cellular populations have emphasized the importance of microbial communities for human health. Constraint-based modeling, with flux balance analysis in particular, has been established as a key approach for studying microbial metabolism, whereas individual-based modeling has been commonly used to study complex dynamics between interacting organisms. In this study, we combine both techniques into the R package BacArena (https://cran.r-project...
May 22, 2017: PLoS Computational Biology
https://www.readbyqxmd.com/read/28531151/an-ensemble-spatiotemporal-model-for-predicting-pm2-5-concentrations
#7
Lianfa Li, Jiehao Zhang, Wenyang Qiu, Jinfeng Wang, Ying Fang
Although fine particulate matter with a diameter of <2.5 μm (PM2.5) has a greater negative impact on human health than particulate matter with a diameter of <10 μm (PM10), measurements of PM2.5 have only recently been performed, and the spatial coverage of these measurements is limited. Comprehensively assessing PM2.5 pollution levels and the cumulative health effects is difficult because PM2.5 monitoring data for prior time periods and certain regions are not available. In this paper, we propose a promising approach for robustly predicting PM2...
May 22, 2017: International Journal of Environmental Research and Public Health
https://www.readbyqxmd.com/read/28530551/angular-velocity-integration-in-a-fly-heading-circuit
#8
Daniel Turner-Evans, Stephanie Wegener, Hervé Rouault, Romain Franconville, Tanya Wolff, Johannes D Seelig, Shaul Druckmann, Vivek Jayaraman
Many animals maintain an internal representation of their heading as they move through their surroundings. Such a compass representation was recently discovered in a neural population in the Drosophila melanogaster central complex, a brain region implicated in spatial navigation. Here, we use two-photon calcium imaging and electrophysiology in head-fixed walking flies to identify a different neural population that conjunctively encodes heading and angular velocity, and is excited selectively by turns in either the clockwise or counterclockwise direction...
May 22, 2017: ELife
https://www.readbyqxmd.com/read/28530492/3d-printing-in-liver-surgery-a-systematic-review
#9
Jan Sylwester Witowski, Jasamine Coles-Black, Tomasz Zbigniew Zuzak, Michał Pędziwiatr, Jason Chuen, Piotr Major, Andrzej Budzyński
BACKGROUND: Rapid growth of three-dimensional (3D) printing in recent years has led to new applications of this technology across all medical fields. This review article presents a broad range of examples on how 3D printing is facilitating liver surgery, including models for preoperative planning, education, and simulation. MATERIALS AND METHODS: We have performed an extensive search of the medical databases Ovid/MEDLINE and PubMed/EMBASE and screened articles fitting the scope of review, following previously established exclusion criteria...
May 22, 2017: Telemedicine Journal and E-health: the Official Journal of the American Telemedicine Association
https://www.readbyqxmd.com/read/28530257/mathematical-model-for-preoperative-identification-of-obstructed-nasal-subsites
#10
M Gamerra, E Cantone, G Sorrentino, R De Luca, M B Russo, E De Corso, F Bossa, A De Vivo, M Iengo
The planning of experimental studies for evaluation of nasal airflow is particularly challenging given the difficulty in obtaining objective measurements in vivo. Although standard rhinomanometry and acoustic rhinometry are the most widely used diagnostic tools for evaluation of nasal airflow, they provide only a global measurement of nasal dynamics, without temporal or spatial details. Furthermore, the numerical simulation of nasal airflow as computational fluid dynamics technology is not validated. Unfortunately, to date, there are no available diagnostic tools to objectively evaluate the geometry of the nasal cavities and to measure nasal resistance and the degree of nasal obstruction, which is of utmost importance for surgical planning...
May 22, 2017: Acta Otorhinolaryngologica Italica
https://www.readbyqxmd.com/read/28530208/eit-imaging-of-admittivities-with-a-d-bar-method-and-spatial-prior-experimental-results-for-absolute-and-difference-imaging
#11
S J Hamilton
Electrical impedance tomography (EIT) is an emerging imaging modality that uses harmless electrical measurements taken on electrodes at a body's surface to recover information about the internal electrical conductivity and or permittivity. The image reconstruction task of EIT is a highly nonlinear inverse problem that is sensitive to noise and modeling errors making the image reconstruction task challenging. D-bar methods solve the nonlinear problem directly, bypassing the need for detailed and time-intensive forward models, to provide absolute (static) as well as time-difference EIT images...
May 22, 2017: Physiological Measurement
https://www.readbyqxmd.com/read/28530205/phantom-experiments-using-soft-prior-regularization-eit-for-breast-cancer-imaging
#12
Ethan K Murphy, Aditya Mahara, Xiaotian Wu, Ryan J Halter
OBJECTIVE: A soft-prior regularization (SR) electrical impedance tomography (EIT) technique for breast cancer imaging is described, which shows an ability to accurately reconstruct tumor/inclusion conductivity values within a dense breast model investigated using a cylindrical and a breast-shaped tank. APPROACH: The SR-EIT method relies on knowing the spatial location of a suspicious lesion initially detected from a second imaging modality. Standard approaches (using Laplace smoothing and total variation regularization) without prior structural information are unable to accurately reconstruct or detect the tumors...
June 2017: Physiological Measurement
https://www.readbyqxmd.com/read/28530167/biofilm-community-succession-a-neutral-perspective
#13
Stephen Woodcock, William T Sloan
Although biofilms represent one of the dominant forms of life in aqueous environments, our understanding of the assembly and development of their microbial communities remains relatively poor. In recent years, several studies have addressed this and have extended the concepts of succession theory in classical ecology into microbial systems. From these datasets, niche-based conceptual models have been developed explaining observed biodiversity patterns and their dynamics. These models have not, however, been formulated mathematically and so remain untested...
May 22, 2017: Microbiology
https://www.readbyqxmd.com/read/28529389/effects-of-greening-and-community-reuse-of-vacant-lots-on-crime
#14
Michelle Kondo, Bernadette Hohl, SeungHoon Han, Charles Branas
The Youngstown Neighborhood Development Corporation initiated a 'Lots of Green' programme to reuse vacant land in 2010. We performed a difference-in-differences analysis of the effects of this programme on crime in and around newly treated lots, in comparison to crimes in and around randomly selected and matched, untreated vacant lot controls. The effects of two types of vacant lot treatments on crime were tested: a cleaning and greening 'stabilisation' treatment and a 'community reuse' treatment mostly involving community gardens...
November 2016: Urban Studies
https://www.readbyqxmd.com/read/28529154/habitat-heterogeneity-hypothesis-and-edge-effects-in-model-metacommunities-marked-manuscript
#15
Michaela Hamm, Barbara Drossel
Spatial heterogeneity is an inherent property of any living environment and is expected to favour biodiversity due to a broader niche space. Furthermore, edges between different habitats can provide additional possibilities for species coexistence. Using computer simulations, this study examines metacommunities consisting of several trophic levels in heterogeneous environments in order to explore the above hypotheses on a community level. We model heterogeneous landscapes by using two different sized resource pools and evaluate the combined effect of dispersal and heterogeneity on local and regional species diversity...
May 18, 2017: Journal of Theoretical Biology
https://www.readbyqxmd.com/read/28528909/melanopsin-contributions-to-the-representation-of-images-in-the-early-visual-system
#16
Annette E Allen, Riccardo Storchi, Franck P Martial, Robert A Bedford, Robert J Lucas
Melanopsin photoreception enhances retinal responses to variations in ambient light (irradiance) and drives non-image-forming visual reflexes such as circadian entrainment [1-6]. Melanopsin signals also reach brain regions responsible for form vision [7-9], but melanopsin's contribution, if any, to encoding visual images remains unclear. We addressed this deficit using principles of receptor silent substitution to present images in which visibility for melanopsin versus rods+cones was independently modulated, and we recorded evoked responses in the mouse dorsal lateral geniculate nucleus (dLGN; thalamic relay for cortical vision)...
May 17, 2017: Current Biology: CB
https://www.readbyqxmd.com/read/28528791/microct-based-finite-element-models-as-a-tool-for-virtual-testing-of-cortical-bone
#17
Masoud Ramezanzadehkoldeh, Bjørn H Skallerud
The aim of this study was to assess a virtual biomechanics testing approach purely based on microcomputed tomography (microCT or µCT) data, providing non-invasive methods for determining the stiffness and strength of cortical bone. Mouse femurs were µCT scanned prior to three-point-bend tests. Then microCT-based finite element models were generated with spatial variation in bone elastoplastic properties and subject-specific femur geometries. Empirical relationships of density versus Young's moduli and yield stress were used in assigning elastoplastic properties to each voxel...
May 18, 2017: Medical Engineering & Physics
https://www.readbyqxmd.com/read/28528742/patterns-of-gun-deaths-across-us-counties-1999-2013
#18
Bindu Kalesan, Sandro Galea
PURPOSE: We examined the socio-demographic distribution of gun deaths across 3143 counties in 50 United States' states to understand the spatial patterns and correlates of high and low gun deaths. METHODS: We used aggregate counts of gun deaths and population in all counties from 1999 to 2013 from the Centers for Disease Control and Prevention's Wide-ranging Online Data for Epidemiologic Research (WONDER). We characterized four levels of gun violence, as distinct levels of gun death rates of relatively safe, unsafe, violent, and extremely violent counties, based on quartiles of 15-year county-specific gun death rates per 100,000 and used negative binomial regression models allowing clustering by state to calculate incidence rate ratios and 95% confidence intervals (95% CIs)...
April 27, 2017: Annals of Epidemiology
https://www.readbyqxmd.com/read/28528635/relocation-is-the-key-to-successful-correlative-fluorescence-and-scanning-electron-microscopy
#19
Delfine Cheng, Gerald Shami, Marco Morsch, Minh Huynh, Patrick Trimby, Filip Braet
In this chapter the authors report on an automated hardware and software solution enabling swift correlative sample array mapping of fluorescently stained molecules within cells and tissues across length scales. Samples are first observed utilizing wide-field optical and fluorescence microscopy, followed by scanning electron microscopy, using calibration points on a dedicated sample-relocation holder. We investigated HeLa cells in vitro, fluorescently labeled for monosialoganglioside one (GM-1), across both imaging platforms within tens of minutes of initial sample preparation...
2017: Methods in Cell Biology
https://www.readbyqxmd.com/read/28528360/a-spiking-neural-network-model-of-the-midbrain-superior-colliculus-that-generates-saccadic-motor-commands
#20
Bahadir Kasap, A John van Opstal
Single-unit recordings suggest that the midbrain superior colliculus (SC) acts as an optimal controller for saccadic gaze shifts. The SC is proposed to be the site within the visuomotor system where the nonlinear spatial-to-temporal transformation is carried out: the population encodes the intended saccade vector by its location in the motor map (spatial), and its trajectory and velocity by the distribution of firing rates (temporal). The neurons' burst profiles vary systematically with their anatomical positions and intended saccade vectors, to account for the nonlinear main-sequence kinematics of saccades...
May 20, 2017: Biological Cybernetics
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