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https://www.readbyqxmd.com/read/29346010/identification-and-correction-of-additive-and-multiplicative-spatial-biases-in-experimental-high-throughput-screening
#1
Bogdan Mazoure, Iurie Caraus, Robert Nadon, Vladimir Makarenkov
Data generated by high-throughput screening (HTS) technologies are prone to spatial bias. Traditionally, bias correction methods used in HTS assume either a simple additive or, more recently, a simple multiplicative spatial bias model. These models do not, however, always provide an accurate correction of measurements in wells located at the intersection of rows and columns affected by spatial bias. The measurements in these wells depend on the nature of interaction between the involved biases. Here, we propose two novel additive and two novel multiplicative spatial bias models accounting for different types of bias interactions...
January 1, 2018: SLAS Discovery
https://www.readbyqxmd.com/read/29345242/joint-estimation-of-activity-and-attenuation-for-pet-using-pragmatic-mr-based-prior-application-to-clinical-tof-pet-mr-whole-body-data-for-fdg-and-non-fdg-tracers
#2
Sangtae Ahn, Lishui Cheng, Dattesh D Shanbhag, Hua Qian, Sandeep S Kaushik, Floris P Jansen, Florian Wiesinger
Accurate and robust attenuation correction remains challenging in hybrid PET/MR particularly for torsos because it is difficult to segment bones, lungs and internal air in MR images. Additionally, MR suffers from susceptibility artifacts when a metallic implant is present. Recently, joint estimation (JE) of activity and attenuation based on PET data, also known as maximum likelihood reconstruction of activity and attenuation (MLAA), has gained considerable interest because of (1) its promise to address the challenges in MR-based attenuation correction (MRAC), and (2) recent advances in time-of-flight (TOF) technology, which is known to be the key to the success of JE...
January 18, 2018: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/29341220/prevalence-of-rhodococcus-equi-from-the-nasal-cavity-of-1-010-apparently-healthy-horses
#3
L T Gressler, G Machado, B P da Silveira, N D Cohen, L G Corbellini, V B Leotti, G N Diehl, L C Dos Santos, A Castagna de Vargas
BACKGROUND: Rhodococcus equi is an important cause of foal pneumonia. While its isolation from different sources has been widely evaluated, there is a need to better understand the R. equi epidemiology from samples of the nasal cavity of healthy horses. OBJECTIVES: To determine the prevalence of R. equi from the nasal cavity of healthy horses, along with its virulence profile, antimicrobial susceptibility, and environmental variables associated. STUDY DESIGN: Cross-sectional study...
January 17, 2018: Equine Veterinary Journal
https://www.readbyqxmd.com/read/29340259/relationships-between-road-distance-to-primary-care-facilities-and-ischemic-heart-disease-and-stroke-mortality-in-hokkaido-japan-a-bayesian-hierarchical-approach-to-ecological-count-data
#4
Yasuaki Saijo, Eiji Yoshioka, Yasuyuki Kawanishi, Yoshihiko Nakagi, Sharon J B Hanley, Takahiko Yoshida
Objective: Poor access to a primary care physician may lead to poor control of risk factors for disease. This study investigated whether geographic access to a primary care physician was related to ischemic heart disease and stroke mortality. Methods: Road-distances from the centroids of the basic unit blocks of the 2010 Japanese Census to the nearest primary care facilities in Hokkaido, northern Japan, were measured using geographic information system (GIS) software...
January 2018: Journal of General and Family Medicine
https://www.readbyqxmd.com/read/29338891/gray-and-white-matter-changes-and-their-relation-to-illness-trajectory-in-first-episode-psychosis
#5
Alejandro Keymer-Gausset, Anna Alonso-Solís, Iluminada Corripio, Rosa B Sauras-Quetcuti, Edith Pomarol-Clotet, Erick J Canales-Rodriguez, Eva Grasa-Bello, Enric Álvarez, Maria J Portella
Previous works have studied structural brain characteristics in first-episode psychosis (FEP), but few have focused on the relation between brain differences and illness trajectories. The aim of this study is to analyze gray and white matter changes in FEP patients and their relation with one-year clinical outcomes. A sample of 41 FEP patients and 41 healthy controls (HC), matched by age and educational level was scanned with a 3T MRI during the first month of illness onset. One year later, patients were assigned to two illness trajectories (schizophrenia and non-schizophrenia)...
January 12, 2018: European Neuropsychopharmacology: the Journal of the European College of Neuropsychopharmacology
https://www.readbyqxmd.com/read/29336906/progression-of-white-matter-damage-in-progressive-supranuclear-palsy-with-predominant-parkinsonism
#6
Francesca Caso, Federica Agosta, Milica Ječmenica-Lukić, Igor Petrović, Alessandro Meani, Vladimir S Kostic, Massimo Filippi
INTRODUCTION: Progressive supranuclear palsy with predominant parkinsonism (PSP-P) accounts for 14-35% of all PSP cases. A few cross-sectional MRI studies in PSP-P showed a remarkable white matter (WM) damage. Progression of brain structural damage in these patients remains unknown. METHODS: Longitudinal clinical, cognitive and diffusion tensor (DT) MRI data were obtained over a mean 1.6 year follow up in 10 PSP-P patients. At study entry, patients were compared with 36 healthy controls...
January 4, 2018: Parkinsonism & related Disorders
https://www.readbyqxmd.com/read/29334860/a-mixed-effects-spatially-varying-coefficients-model-with-application-to-multi-resolution-functional-magnetic-resonance-imaging-data
#7
Zhuqing Liu, Andreas J Bartsch, Veronica J Berrocal, Timothy D Johnson
Spatial resolution plays an important role in functional magnetic resonance imaging studies as the signal-to-noise ratio increases linearly with voxel volume. In scientific studies, where functional magnetic resonance imaging is widely used, the standard spatial resolution typically used is relatively low which ensures a relatively high signal-to-noise ratio. However, for pre-surgical functional magnetic resonance imaging analysis, where spatial accuracy is paramount, high-resolution functional magnetic resonance imaging may play an important role with its greater spatial resolution...
January 1, 2018: Statistical Methods in Medical Research
https://www.readbyqxmd.com/read/29334156/the-retinal-ganglion-cell-layer-predicts-normal-appearing-white-matter-tract-integrity-in-multiple-sclerosis-a-combined-diffusion-tensor-imaging-and-optical-coherence-tomography-approach
#8
Carolina Alves, Sónia Batista, Otília C d'Almeida, Lívia Sousa, Luís Cunha, Rui Bernardes, Miguel Castelo-Branco
We investigated the relationship between retinal layers and normal-appearing white matter (WM) integrity in the brain of patients with relapsing-remitting multiple sclerosis (MS), using a combined diffusion tensor imaging and high resolution optical coherence tomography approach. Fifty patients and 62 controls were recruited. The patients were divided into two groups according to presence (n = 18) or absence (n = 32) of optic neuritis. Diffusion tensor data were analyzed with a voxel-wise whole brain analysis of diffusion metrics in WM with tract-based spatial statistics...
January 15, 2018: Human Brain Mapping
https://www.readbyqxmd.com/read/29333346/boundaries-in-ground-beetle-coleoptera-carabidae-and-environmental-variables-at-the-edges-of-forest-patches-with-residential-developments
#9
Doreen E Davis, Sara A Gagné
Background: Few studies of edge effects on wildlife objectively identify habitat edges or explore non-linear responses. In this paper, we build on ground beetle (Coleoptera: Carabidae) research that has begun to address these domains by using triangulation wombling to identify boundaries in beetle community structure and composition at the edges of forest patches with residential developments. We hypothesized that edges are characterized by boundaries in environmental variables that correspond to marked discontinuities in vegetation structure between maintained yards and forest...
2018: PeerJ
https://www.readbyqxmd.com/read/29331279/dynamics-of-spatiotemporal-distribution-of-schistosomiasis-in-hubei-province-china
#10
Yan-Yan Chen, Jian-Bing Liu, Yong Jiang, Guo Li, Xiao-Wei Shan, Juan Zhang, Shun-Xiang Cai, Xi-Bao Huang
Schistosomiasis caused by parasitic flatworms of blood flukes, remains a major public health concern in China. The significant progress in controlling schistosomiasis in China over the past decades has resulted in the remarkable reduction in the prevalence and intensity of Schistosoma japonicum infection to an extremely low level. Therefore, the elimination of schistosomiasis has been promoted by the Chinese national government. Hubei Province is the major endemic area, that is, along the middle and low reaches of the Yangtze River in the lake and marshland regions of southern China...
January 10, 2018: Acta Tropica
https://www.readbyqxmd.com/read/29330454/dynamic-malaria-hotspots-in-an-open-cohort-in-western-kenya
#11
Alyssa Platt, Andrew A Obala, Charlie MacIntyre, Barasa Otsyula, Wendy Prudhomme O' Meara
Malaria hotspots, defined as areas where transmission intensity exceeds the average level, become more pronounced as transmission declines. Targeting hotspots may accelerate reductions in transmission and could be pivotal for malaria elimination. Determinants of hotspot location, particularly of their movement, are poorly understood. We used spatial statistical methods to identify foci of incidence of self-reported malaria in a large census population of 64,000 people, in 8,290 compounds over a 2.5-year study period...
January 12, 2018: Scientific Reports
https://www.readbyqxmd.com/read/29329574/microcephaly-epidemic-related-to-the-zika-virus-and-living-conditions-in-recife-northeast-brazil
#12
Wayner Vieira de Souza, Maria de Fátima Pessoa Militão de Albuquerque, Enrique Vazquez, Luciana Caroline Albuquerque Bezerra, Antonio da Cruz Gouveia Mendes, Tereza Maciel Lyra, Thalia Velho Barreto de Araujo, André Luiz Sá de Oliveira, Maria Cynthia Braga, Ricardo Arraes de Alencar Ximenes, Demócrito de Barros Miranda-Filho, Amanda Priscila de Santana Cabral Silva, Laura Rodrigues, Celina Maria Turchi Martelli
BACKGROUND: Starting in August 2015, there was an increase in the number of cases of neonatal microcephaly in Northeast Brazil. These findings were identified as being an epidemic of microcephaly related to Zika virus (ZIKV) infection. The present study aims to analyse the spatial distribution of microcephaly cases in Recife (2015-2016), which is in Northeast Brazil, and its association with the living conditions in this city. METHODS: This was an ecological study that used data from reported cases of microcephaly from the State Health Department of Pernambuco (August 2015 to July 2016)...
January 12, 2018: BMC Public Health
https://www.readbyqxmd.com/read/29329016/non-linear-effects-of-the-built-environment-on-automobile-involved-pedestrian-crash-frequency-a-machine-learning-approach
#13
Chuan Ding, Peng Chen, Junfeng Jiao
Although a growing body of literature focuses on the relationship between the built environment and pedestrian crashes, limited evidence is provided about the relative importance of many built environment attributes by accounting for their mutual interaction effects and their non-linear effects on automobile-involved pedestrian crashes. This study adopts the approach of Multiple Additive Poisson Regression Trees (MAPRT) to fill such gaps using pedestrian collision data collected from Seattle, Washington. Traffic analysis zones are chosen as the analytical unit...
January 9, 2018: Accident; Analysis and Prevention
https://www.readbyqxmd.com/read/29326869/prenatal-methadone-exposure-is-associated-with-altered-neonatal-brain-development
#14
Victoria J Monnelly, Devasuda Anblagan, Alan Quigley, Manuel Blesa Cabez, E Sarah Cooper, Helen Mactier, Scott I Semple, Mark E Bastin, James P Boardman
Methadone is used for medication-assisted treatment of heroin addiction during pregnancy. The neurodevelopmental outcome of children with prenatal methadone exposure can be sub-optimal. We tested the hypothesis that brain development is altered among newborn infants whose mothers were prescribed methadone. 20 methadone-exposed neonates born after 37 weeks' postmenstrual age (PMA) and 20 non-exposed controls underwent diffusion MRI at mean PMA of 39+ 2 and 41+ 1 weeks, respectively. An age-optimized Tract-based Spatial Statistics (TBSS) pipeline was used to perform voxel-wise statistical comparison of fractional anisotropy (FA) data between exposed and non-exposed neonates...
2018: NeuroImage: Clinical
https://www.readbyqxmd.com/read/29326046/multi-tissue-partial-volume-quantification-in-multi-contrast-mri-using-an-optimised-spectral-unmixing-approach
#15
Guylaine Collewet, Saïd Moussaoui, Cécile Deligny, Tiphaine Lucas, Jérôme Idier
Multi-tissue partial volume estimation in MRI images is investigated with a viewpoint related to spectral unmixing as used in hyperspectral imaging. The main contribution of this paper is twofold. It firstly proposes a theoretical analysis of the statistical optimality conditions of the proportion estimation problem, which in the context of multi-contrast MRI data acquisition allows to appropriately set the imaging sequence parameters. Secondly, an efficient proportion quantification algorithm based on the minimisation of a penalised least-square criterion incorporating a regularity constraint on the spatial distribution of the proportions is proposed...
January 8, 2018: Magnetic Resonance Imaging
https://www.readbyqxmd.com/read/29325356/-the-role-and-significance-of-digital-reconstruction-technique-in-liver-segments-based-on-portal-vein-structure
#16
X J Zhou, Q Dong, C Z Zhu, X Chen, B Wei, Y H Duan, J Zhao, X W Hao, H Zhang, P Nie, B Hu, W J Xu, R W Shen, Z H Chen, K R Dong, Y Z Bai, Q Shu, W J Luo, F Gao, N Xia, Q Y Yu
Objective: To study the segment of liver according to the large amount of three-dimensional(3D) reconstructive images of normal human livers and the vascular system, and to recognize the basic functional liver unit based on the anatomic features of the intrahepatic portal veins. Methods: The enhanced CT primitive DICOM files of 1 260 normal human livers from different age groups who treated from October 2013 to February 2017 provided by 16 hospitals were analyzed using the computer-aided surgery system.The 3D liver and liver vascular system were reconstructed, and the digital liver 3D model was established...
January 1, 2018: Zhonghua Wai Ke za Zhi [Chinese Journal of Surgery]
https://www.readbyqxmd.com/read/29324887/the-tracked-roaming-transect-and-distance-sampling-methods-increase-the-efficiency-of-underwater-visual-censuses
#17
Alejo J Irigoyen, Irene Rojo, Antonio Calò, Gastón Trobbiani, Noela Sánchez-Carnero, José A García-Charton
Underwater visual census (UVC) is the most common approach for estimating diversity, abundance and size of reef fishes in shallow and clear waters. Abundance estimation through UVC is particularly problematic in species occurring at low densities and/or highly aggregated because of their high variability at both spatial and temporal scales. The statistical power of experiments involving UVC techniques may be increased by augmenting the number of replicates or the area surveyed. In this work we present and test the efficiency of an UVC method based on diver towed GPS, the Tracked Roaming Transect (TRT), designed to maximize transect length (and thus the surveyed area) with respect to diving time invested in monitoring, as compared to Conventional Strip Transects (CST)...
2018: PloS One
https://www.readbyqxmd.com/read/29324760/bionomics-of-phlebotomus-argentipes-in-villages-in-bihar-india-with-insights-into-efficacy-of-irs-based-control-measures
#18
David M Poché, Rajesh B Garlapati, Shanta Mukherjee, Zaria Torres-Poché, Epco Hasker, Tahfizur Rahman, Aakanksha Bharti, Vishnu P Tripathi, Suman Prakash, Rahul Chaubey, Richard M Poché
BACKGROUND: Visceral leishmaniasis (VL) is a deadly vector-borne disease. Approximately 90% of Indian VL cases occur in Bihar, where the sand fly, Phlebotomus argentipes, is the principal vector. Sand fly control in Bihar consists of indoor residual spraying (IRS), the practice of spraying the inner walls of village dwellings with insecticides. Prior researchers have evaluated success of IRS-control by estimating vector abundance in village houses, but the number of sampling periods (n = 2-3) were minimal, and outdoor-resting P...
January 2018: PLoS Neglected Tropical Diseases
https://www.readbyqxmd.com/read/29324671/spatiotemporal-patterns-of-ground-monitored-pm2-5-concentrations-in-china-in-recent-years
#19
Junming Li, Xiulan Han, Xiao Li, Jianping Yang, Xuejiao Li
This paper firstly explores the space-time evolution of city-level PM 2.5 concentrations showed a very significant seasonal cycle type fluctuation during the period between 13 May 2014 and 30 May 2017. The period from October to April following each year was a heavy pollution period, whereas the phase from April to October of the current year was part of a light pollution period. The average monthly PM 2.5 concentrations in mainland China based on ground monitoring, employing a descriptive statistics method and a Bayesian spatiotemporal hierarchy model...
January 11, 2018: International Journal of Environmental Research and Public Health
https://www.readbyqxmd.com/read/29324400/determination-of-atomic-positions-from-time-resolved-high-resolution-transmission-electron-microscopy-images
#20
Zahra Hussaini, Pin Ann Lin, Bharath Natarajan, Wenhui Zhu, Renu Sharma
For many reaction processes, such as catalysis, phase transformations, nanomaterial synthesis etc., nanoscale observations at high spatial (sub-nanometer) and temporal (millisecond) resolution are required to characterize and comprehend the underlying factors that favor one reaction over another. The combination of such spatial and temporal resolution (up to 600 µs), while rich in information, produces a large number of snapshots, each of which must be analyzed to obtain the structural (and thereby chemical) information...
December 28, 2017: Ultramicroscopy
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