keyword
MENU ▼
Read by QxMD icon Read
search

Spatial statistics

keyword
https://www.readbyqxmd.com/read/28446580/entrainment-of-visual-steady-state-responses-is-modulated-by-global-spatial-statistics
#1
Thomas Nguyen, Karl Kuntzelman, Vladimir Miskovic
The rhythmic delivery of visual stimuli evokes large-scale neuronal entrainment in the form of steady-state oscillatory field responses. The spatio-temporal properties of stimulus drive appear to constrain the relative degrees of neuronal entrainment. Specific frequency ranges, for example, are uniquely suited for enhancing the strength of stimulus-driven brain oscillations. When it comes to the nature of the visual stimulus itself, studies have used a plethora of inputs ranging from spatially unstructured empty fields to simple contrast patterns (checkerboards, gratings, stripes) and complex arrays (human faces, houses, natural scenes)...
April 26, 2017: Journal of Neurophysiology
https://www.readbyqxmd.com/read/28445430/impact-of-land-use-on-pm2-5-pollution-in-a-representative-city-of-middle-china
#2
Haiou Yang, Wenbo Chen, Zhaofeng Liang
Fine particulate matter (PM2.5) pollution has become one of the greatest urban issues in China. Studies have shown that PM2.5 pollution is strongly related to the land use pattern at the micro-scale and optimizing the land use pattern has been suggested as an approach to mitigate PM2.5 pollution. However, there are only a few researches analyzing the effect of land use on PM2.5 pollution. This paper employed land use regression (LUR) models and statistical analysis to explore the effect of land use on PM2.5 pollution in urban areas...
April 26, 2017: International Journal of Environmental Research and Public Health
https://www.readbyqxmd.com/read/28445309/exploring-spatial-patterns-of-acupoint-indications-from-clinical-data-a-strobe-compliant-article
#3
Won-Mo Jung, Soon-Ho Lee, Ye-Seul Lee, Younbyoung Chae
Every acupoint has specific indications for acupuncture treatment. These indications, primarily established based on the meridian system, have spatial patterns of symptoms on the human body. We investigated the associations between acupoints and symptom locations in 75 patients with chronic pain who were asked to sketch the localization of their symptoms on body schemes using the bodily sensation map (BSM) system. Combining the BSM and clinical information, we estimated the statistical parameters of relationships between acupoints and spatial information on symptoms...
April 2017: Medicine (Baltimore)
https://www.readbyqxmd.com/read/28444799/pixel-wise-estimation-of-noise-statistics-on-iterative-ct-reconstruction-from-a-single-scan
#4
Tonghe Wang, Lei Zhu
PURPOSE: As iterative CT reconstruction continues to advance, the spatial distribution of noise standard deviation (STD) and accurate noise power spectrum (NPS) on the reconstructed CT images become important for method evaluation as well as optimization of algorithm parameters. Using a single CT scan, we propose a practical method for pixel-wise calculation of noise statistics on an iteratively reconstructed CT image, which enables accurate calculation of noise STD for each pixel and NPS...
April 26, 2017: Medical Physics
https://www.readbyqxmd.com/read/28444426/investigation-of-altered-microstructure-in-patients-with-drug-refractory-epilepsy-using-diffusion-tensor-imaging
#5
Yuwei Jiang, Lingyan Mao, Xu Yan, Mingxia Fan, Xin Wang, Jing Ding, Dongrong Xu
PURPOSE: The risk of refractory epilepsy can be more dangerous than the adverse effect caused by medical treatment. In this study, we employed voxel-wise analysis (VWA) and tract-based spatial statistics (TBSS) methods to measure microstructural changes using diffusion tensor imaging (DTI) in patients of drug refractory epilepsy (DRE) who had been epileptic for more than 10 years. METHODS: To examine the specific microstructural abnormalities in DRE patients and its difference from medically controlled epilepsy (MCE), we acquired DTI data of 7 DRE patients, 37 MCE patients, and 31 healthy controls (HCs) using a 3 T MRI scanner...
April 25, 2017: Neuroradiology
https://www.readbyqxmd.com/read/28444422/continuity-vs-the-crowd-tradeoffs-between-continuous-and-intermittent-citizen-hydrology-streamflow-observations
#6
Jeffrey C Davids, Nick van de Giesen, Martine Rutten
Hydrologic data has traditionally been collected with permanent installations of sophisticated and accurate but expensive monitoring equipment at limited numbers of sites. Consequently, observation frequency and costs are high, but spatial coverage of the data is limited. Citizen Hydrology can possibly overcome these challenges by leveraging easily scaled mobile technology and local residents to collect hydrologic data at many sites. However, understanding of how decreased observational frequency impacts the accuracy of key streamflow statistics such as minimum flow, maximum flow, and runoff is limited...
April 25, 2017: Environmental Management
https://www.readbyqxmd.com/read/28443694/fractal-features-and-surface-micromorphology-of-unworn-surfaces-of-rigid-gas-permeable-contact-lenses
#7
Ştefan Ţălu, Miroslaw Bramowicz, Slawomir Kulesza, Ilenia Fiorillo, Stefano Giovanzana
PURPOSE: The aim of this exploratory study was to investigate the micromorphology of surfaces of rigid gas permeable (RGP) contact lenses (CLs) using atomic force microscopy (AFM) followed by fractal analysis. MATERIALS AND METHODS: In order to characterize in a quantitative manner the micromorphology of surfaces of new and unworn RGP CLs made of twelve different materials, AFM was taken and then analyzed using fractal methods. Surface topography was sampled in an intermittent-contact mode in air, on square areas of 5 × 5 µm(2) (MultiMode with Nanoscope V (Bruker)...
April 26, 2017: Current Eye Research
https://www.readbyqxmd.com/read/28441957/landscape-structure-affects-distribution-of-potential-disease-vectors-diptera-culicidae
#8
Carina Zittra, Simon Vitecek, Adelheid G Obwaller, Heidemarie Rossiter, Barbara Eigner, Thomas Zechmeister, Johann Waringer, Hans-Peter Fuehrer
BACKGROUND: Vector-pathogen dynamics are controlled by fluctuations of potential vector communities, such as the Culicidae. Assessment of mosquito community diversity and, in particular, identification of environmental parameters shaping these communities is therefore of key importance for the design of adequate surveillance approaches. In this study, we assess effects of climatic parameters and habitat structure on mosquito communities in eastern Austria to deliver these highly relevant baseline data...
April 26, 2017: Parasites & Vectors
https://www.readbyqxmd.com/read/28437669/white-matter-microstructural-abnormalities-and-their-association-with-anticipatory-anhedonia-in-depression
#9
Xin-Hua Yang, Yi Wang, Dong-Fang Wang, Kai Tian, Eric F C Cheung, Guang-Rong Xie, Raymond C K Chan
Anhedonia is associated with dysfunction of the neural circuitry of reward in patients with major depressive disorder (MDD). However, its neurobiological basis is not fully understood. The present study examined the association between anhedonia and white matter (WM) characteristics in patients with first-episode MDD. We recruited 30 patients with first-episode drug-naive MDD and 28 healthy controls (HC) to undergo diffusion weighted imaging. We examined specifically the correlation between WM characteristics and anhedonia measured with the Temporal Experience of Pleasure Scale (TEPS) in MDD patients...
April 13, 2017: Psychiatry Research
https://www.readbyqxmd.com/read/28437486/prediction-of-crime-occurrence-from-multi-modal-data-using-deep-learning
#10
Hyeon-Woo Kang, Hang-Bong Kang
In recent years, various studies have been conducted on the prediction of crime occurrences. This predictive capability is intended to assist in crime prevention by facilitating effective implementation of police patrols. Previous studies have used data from multiple domains such as demographics, economics, and education. Their prediction models treat data from different domains equally. These methods have problems in crime occurrence prediction, such as difficulty in discovering highly nonlinear relationships, redundancies, and dependencies between multiple datasets...
2017: PloS One
https://www.readbyqxmd.com/read/28437444/transcriptional-bursting-in-drosophila-development-stochastic-dynamics-of-eve-stripe-2-expression
#11
David M Holloway, Alexander V Spirov
Anterior-posterior (AP) body segmentation of the fruit fly (Drosophila) is first seen in the 7-stripe spatial expression patterns of the pair-rule genes, which regulate downstream genes determining specific segment identities. Regulation of pair-rule expression has been extensively studied for the even-skipped (eve) gene. Recent live imaging, of a reporter for the 2nd eve stripe, has demonstrated the stochastic nature of this process, with 'bursts' in the number of RNA transcripts being made over time. We developed a stochastic model of the spatial and temporal expression of eve stripe 2 (binding by transcriptional activators (Bicoid and Hunchback proteins) and repressors (Giant and Krüppel proteins), transcriptional initiation and termination; with all rate parameters constrained by features of the experimental data) in order to analyze the noisy experimental time series and test hypotheses for how eve transcription is regulated...
2017: PloS One
https://www.readbyqxmd.com/read/28437439/landscape-and-environmental-influences-on-mycobacterium-ulcerans-distribution-among-aquatic-sites-in-ghana
#12
Shannon M Pileggi, Heather Jordan, Julie A Clennon, Ellen Whitney, M Eric Benbow, Richard Merritt, Mollie McIntosh, Ryan Kimbirauskas, Pamela Small, Daniel Boakye, Charles Quaye, Jiaguo Qi, Lindsay Campbell, Jenni Gronseth, Edwin Ampadu, William Opare, Lance A Waller
Buruli ulcer, caused by Mycobacterium ulcerans, is highly endemic in West Africa. While the mode of transmission is unknown, many studies associate Buruli ulcer with different types of water exposure. We present results from the largest study to date to test for M. ulcerans in aquatic sites and identify environmental attributes associated with its presence. Environmental samples from 98 aquatic sites in the Greater Accra, Ashanti, and Volta regions of Ghana were tested for the presence of M. ulcerans DNA by polymerase chain reaction...
2017: PloS One
https://www.readbyqxmd.com/read/28436450/definition-of-fractal-topography-to-essential-understanding-of-scale-invariance
#13
Yi Jin, Ying Wu, Hui Li, Mengyu Zhao, Jienan Pan
Fractal behavior is scale-invariant and widely characterized by fractal dimension. However, the cor-respondence between them is that fractal behavior uniquely determines a fractal dimension while a fractal dimension can be related to many possible fractal behaviors. Therefore, fractal behavior is independent of the fractal generator and its geometries, spatial pattern, and statistical properties in addition to scale. To mathematically describe fractal behavior, we propose a novel concept of fractal topography defined by two scale-invariant parameters, scaling lacunarity (P) and scaling coverage (F)...
April 24, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28435374/spatial-analysis-of-mandibular-condyles-in-patients-with-temporomandibular-disorders-and-normal-controls-using-cone-beam-computed-tomography
#14
Natheer Hashim Al-Rawi, Asmaa Tahseen Uthman, Sahar M Sodeify
OBJECTIVES: The aim of the study is to investigate the condylar position and its relation to articular eminence and axial condylar angle in temporomandibular joint disorder (TMD) patients and in normal controls using cone beam computed tomography (CBCT). MATERIALS AND METHODS: CBCT temporomandibular joint (TMJ) images of 70 participants (38 males and 32 females, mean age 26.4 years) were analyzed. They were divided into control group (including 35 subjects) and study group (including 35 subjects)...
January 2017: European Journal of Dentistry
https://www.readbyqxmd.com/read/28433817/climate-change-risks-extinction-debt-and-conservation-implications-for-a-threatened-freshwater-fish-carmine-shiner-notropis-percobromus
#15
Shubha N Pandit, Bryan M Maitland, Laxmi K Pandit, Mark S Poesch, Eva C Enders
Climate change is affecting many freshwater species, particularly fishes. Predictions of future climate change suggest large and deleterious effects on species with narrow dispersal abilities due to limited hydrological connectivity. In turn, this creates the potential for population isolation in thermally unsuitable habitats, leading to physiological stress, species declines or possible extirpation. The current extent of many freshwater fish species' spatio-temporal distribution patterns and their sensitivity to thermal impacts from climate change - critical information for conservation planning - are often unknown...
April 20, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28432182/toward-a-direct-and-scalable-identification-of-reduced-models-for-categorical-processes
#16
Susanne Gerber, Illia Horenko
The applicability of many computational approaches is dwelling on the identification of reduced models defined on a small set of collective variables (colvars). A methodology for scalable probability-preserving identification of reduced models and colvars directly from the data is derived-not relying on the availability of the full relation matrices at any stage of the resulting algorithm, allowing for a robust quantification of reduced model uncertainty and allowing us to impose a priori available physical information...
April 21, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28431605/global-brain-atrophy-and-metabolic-dysfunction-in-lgi1-encephalitis-a-prospective-multimodal-mri-study
#17
Monika Szots, Morten Blaabjerg, Gergely Orsi, Pernille Iversen, Daniel Kondziella, Camilla G Madsen, Ellen Garde, Peter O Magnusson, Peter Barsi, Ferenc Nagy, Hartwig R Siebner, Zsolt Illes
BACKGROUND: Chronic cognitive deficits are frequent in leucin-rich glioma-inactivated 1 protein (LGI1) encephalitis. We examined structural and metabolic brain abnormalities following LGI1 encephalitis and correlated findings with acute and follow-up clinical outcomes. METHODS: Nine patients underwent prospective multimodal 3 Tesla MRI 33.1±18months after disease onset, including automated volumetry, diffusion tensor imaging (DTI) and magnetic resonance spectroscopy (MRS)...
May 15, 2017: Journal of the Neurological Sciences
https://www.readbyqxmd.com/read/28430788/time-and-spatial-trends-in-lymphoid-leukemia-and-lymphoma-incidence-and-survival-among-children-and-adolescents-in-manitoba-canada-1984-2013
#18
Xibiao Ye, Mahmoud Torabi, Lisa M Lix, Salaheddin M Mahmud
OBJECTIVES: To test for time and spatial trends in lymphoid malignancies, including lymphoid leukemia (LL), Hodgkin lymphoma (HL), and non-Hodgkin lymphoma (NHL), in children and adolescents in the province of Manitoba, Canada. METHODS: Incident cases diagnosed between 1984 and 2013 were identified from the Manitoba Cancer Registry. We assessed time trends in age-standardized incidence rates using joinpoint regression and in 5-year relative survival using Poisson regression model...
2017: PloS One
https://www.readbyqxmd.com/read/28430705/disparities-in-female-breast-cancer-stage-at-diagnosis-in-new-jersey-a-spatial-temporal-analysis
#19
Lisa M Roche, Xiaoling Niu, Antoinette M Stroup, Kevin A Henry
BACKGROUND: Despite improvements in early detection of breast cancer, disparities persist in stage at diagnosis, which is an important prognostic factor. METHODS: We used the space-time scan statistic in SaTScan to identify geographic areas and time periods with significantly elevated proportions of female breast cancer diagnosed at the in situ or distant stage in New Jersey. The analyses were conducted with census tracts as the geographic unit of analysis, elliptical spatial windows, 3-year temporal windows, and Poisson models...
December 22, 2016: Journal of Public Health Management and Practice: JPHMP
https://www.readbyqxmd.com/read/28429904/effect-of-lutein-supplementation-on-visual-function-in-nonproliferative-diabetic-retinopathy
#20
Ping-Chuan Zhang, Chang-Rui Wu, Zhi-Lun Wang, Li-Yuan Wang, Yue Han, Shu-Liu Sun, Qing-Shan Li, Le Ma
BACKGROUND AND OBJECTIVES: The purpose of this study was to determine whether supplementation with lutein improved visual function in patients with nonproliferative diabetic retinopathy (NPDR). METHODS AND STUDY DESIGN: In this randomized, double-blind, placebo-controlled trial, 31 patients with NPDR were assigned randomly to 10 mg/d of lutein or identical placebo for 36 weeks. Visual performance indices, including visual acuity (VA), contrast sensitivity (CS) and glare sensitivity (GS) at four different spatial frequencies, were measured at baseline, week 18 and 36...
May 2017: Asia Pacific Journal of Clinical Nutrition
keyword
keyword
9516
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"