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William H Curley, Peter B Forgacs, Henning U Voss, Mary M Conte, Nicholas D Schiff
Patients with severe brain injury are difficult to assess and frequently subject to misdiagnosis. 'Cognitive motor dissociation' is a term used to describe a subset of such patients with preserved cognition as detected with neuroimaging methods but not evident in behavioural assessments. Unlike the locked-in state, cognitive motor dissociation after severe brain injury is prominently marked by concomitant injuries across the cerebrum in addition to limited or no motoric function. In the present study, we sought to characterize the EEG signals used as indicators of cognition in patients with disorders of consciousness and examine their reliability for potential future use to re-establish communication...
March 19, 2018: Brain: a Journal of Neurology
Jesse D Berman, Thomas M Peters, Kirsten A Koehler
Objectives: To design a method that uses preliminary hazard mapping data to optimize the number and location of sensors within a network for a long-term assessment of occupational concentrations, while preserving temporal variability, accuracy, and precision of predicted hazards. Methods: Particle number concentrations (PNCs) and respirable mass concentrations (RMCs) were measured with direct-reading instruments in a large heavy-vehicle manufacturing facility at 80-82 locations during 7 mapping events, stratified by day and season...
March 17, 2018: Annals of Work Exposures and Health
Tomáš Glomb, Adam Mertel, Zdeněk Pospíšil, Zdeněk Stachoň, Aleš Chalupa
Early in the Ptolemaic era, Egyptian cults, particularly those of Isis and Sarapis, spread successfully to ports across the ancient Aegean Sea. Leading researchers in the field claim that the spread of these cults was influenced by multiple factors, ones that were mainly economic or political in character. However, the question of which factors had more weight or impact than others in the process of the early spread of Egyptian cults has not yet been answered in academic discussion. This could be related to the fact that the issue of the spread of religious innovations in the ancient Mediterranean has been addressed mainly by established historiographical methods such as the collection and critical analysis of archaeological and literary sources...
2018: PloS One
Gehendra Mahara, Kun Yang, Sipeng Chen, Wei Wang, Xiuhua Guo
Evidence shows that multiple factors, such as socio-economic status and access to health care facilities, affect tuberculosis (TB) incidence. However, there is limited literature available with respect to the correlation between socio-economic/health facility factors and tuberculosis incidence. This study aimed to explore the relationship between TB incidence and socio-economic/health service predictors in the study settings. A retrospective spatial regression analysis was carried out based on new sputum smear-positive pulmonary TB cases in Beijing districts...
March 21, 2018: Medical Sciences: Open Access Journal
Tadanori Fukami, Takamasa Shimada, Bunnoshin Ishikawa
OBJECTIVE: In the current study, we tested a proposed method for fast spike detection in electroencephalography (EEG). APPROACH: We performed eigenvalue analysis in two-dimensional space spanned by gradients calculated from two neighboring samples to detect high-amplitude negative peaks. We extracted the spike candidates by imposing restrictions on parameters regarding spike shape and eigenvalues reflecting detection characteristics of individual medical doctors...
March 21, 2018: Journal of Neural Engineering
Lisa-Katrin Kaufmann, Volker Baur, Jürgen Hänggi, Lutz Jäncke, Marco Piccirelli, Spyros Kollias, Ulrich Schnyder, Ofer Pasternak, Chantal Martin-Soelch, Gabriella Milos
BACKGROUND: Acute anorexia nervosa (AN) is characterized by reduced brain mass and corresponding increased sulcal and ventricular cerebrospinal fluid. Recent studies of white matter using diffusion tensor imaging consistently identified alterations in the fornix, such as reduced fractional anisotropy (FA). However, because the fornix penetrates the ventricles, it is prone to cerebrospinal fluid-induced partial volume effects that interfere with a valid assessment of FA. We investigated the hypothesis that in the acute stage of AN, FA of the fornix is markedly affected by ventricular volumes...
July 2017: Biological Psychiatry: Cognitive Neuroscience and Neuroimaging
Jan Kassubek, Hans-Peter Müller, Kelly Del Tredici, Michael Hornberger, Matthias L Schroeter, Karsten Müller, Sarah Anderl-Straub, Ingo Uttner, Murray Grossman, Heiko Braak, John R Hodges, Olivier Piguet, Markus Otto, Albert C Ludolph
Objective: Recently, the characteristic longitudinal distribution pattern of the underlying phosphorylated TDP-43 (pTDP-43) pathology in the behavioral variant of frontotemporal dementia (bvFTD) excluding Pick's disease (PiD) across specific brain regions was described. The aim of the present study was to investigate whether in vivo investigations of bvFTD patients by use of diffusion tensor imaging (DTI) were consistent with these proposed patterns of progression. Methods: Sixty-two bvFTD patients and 47 controls underwent DTI in a multicenter study design...
2018: Frontiers in Aging Neuroscience
Manuel Bratos, Jumping M Bergin, Jeffrey E Rubenstein, John A Sorensen
STATEMENT OF PROBLEM: Conventional impression techniques to obtain a definitive cast for a complete-arch implant-supported prosthesis are technique-sensitive and time-consuming. Direct optical recording with a camera could offer an alternative to conventional impression making. PURPOSE: The purpose of this in vitro study was to test a novel intraoral image capture protocol to obtain 3-dimensional (3D) implant spatial measurement data under simulated oral conditions of vertical opening and lip retraction...
March 17, 2018: Journal of Prosthetic Dentistry
C Ladha, Z Belshaw, J O'Sullivan, L Asher
BACKGROUND: Accelerometer-based technologies could be useful in providing objective measures of canine ambulation, but most are either not tailored to the idiosyncrasies of canine gait, or, use un-validated or closed source approaches. The aim of this paper was to validate algorithms which could be applied to accelerometer data for i) counting the number of steps and ii) distance travelled by a dog. To count steps, an approach based on partitioning acceleration was used. This was applied to accelerometer data from 13 dogs which were walked a set distance and filmed...
March 20, 2018: BMC Veterinary Research
Patryk Zradziński
PURPOSE: In this work, the inter-person variability of hazards caused by a low frequency magnetic field exposure (of various polarisation and homogeneity near to the magneto therapy applicator) to users of BAHA hearing implants were investigated with respect to various head structures. MATERIAL AND METHODS: The effects of exposure were evaluated by numerical simulations of the electric field (Ein ) induced in head phantoms (regular or with implant model). Phantoms mimic head dimensions and thicknesses of layers of skin, fat, skull bones and brain...
March 20, 2018: International Journal of Radiation Biology
Georgios Samiotis, Eleni Trikoilidou, Lazaros Tsikritzis, Elisavet Amanatidou
In this work, a comparative study on the water quality characteristics of two in-line water reservoirs (artificial lakes) in Aliakmon River (Western Macedonia, Greece) is performed. Polyfytos Reservoir and Ilarion Reservoir were created in 1975 and 2012 respectively, in order to serve the homonymous hydroelectric stations. In young artificial lakes, severe deterioration of water quality may occur; thus, the monitoring and assessment of their water quality characteristics and their statistical interpretation are of great importance...
March 20, 2018: Environmental Monitoring and Assessment
Yoshitaka Inui, Takashi Ichihara, Masaki Uno, Masanobu Ishiguro, Kengo Ito, Katsuhiko Kato, Hajime Sakuma, Hidehiko Okazawa, Hiroshi Toyama
OBJECTIVE: Statistical image analysis of brain SPECT images has improved diagnostic accuracy for brain disorders. However, the results of statistical analysis vary depending on the institution even when they use a common normal database (NDB), due to different intrinsic spatial resolutions or correction methods. The present study aimed to evaluate the correction of spatial resolution differences between equipment and examine the differences in skull bone attenuation to construct a common NDB for use in multicenter settings...
March 19, 2018: Annals of Nuclear Medicine
Nathaniel Narra, Shinya Abe, Vassil Dimitrov, Riku Nikander, Reijo Kouhia, Harri Sievänen, Jari Hyttinen
The causal relationship between habitual loading and adaptive response in bone morphology is commonly explored by analysing the spatial distribution of mechanically relevant features. In this study, 3D distribution of features in the proximal femur of 91 female athletes (5 exercise loading groups representing habitual loading) is contrasted with 20 controls. A femur specific Ricci-flow based conformal mapping procedure was developed for establishing correspondence among the periosteal surfaces. The procedure leverages the invariance of the conformal mapping method to isometric shape differences to align surfaces in the 2D parametric domain, to produce dense correspondences across an isotopological set of surfaces...
March 19, 2018: Scientific Reports
N A Wardrop, W C Jochem, T J Bird, H R Chamberlain, D Clarke, D Kerr, L Bengtsson, S Juran, V Seaman, A J Tatem
Population numbers at local levels are fundamental data for many applications, including the delivery and planning of services, election preparation, and response to disasters. In resource-poor settings, recent and reliable demographic data at subnational scales can often be lacking. National population and housing census data can be outdated, inaccurate, or missing key groups or areas, while registry data are generally lacking or incomplete. Moreover, at local scales accurate boundary data are often limited, and high rates of migration and urban growth make existing data quickly outdated...
March 19, 2018: Proceedings of the National Academy of Sciences of the United States of America
Xufeng Fei, Wanzhen Chen, Shuqing Zhang, Qingmin Liu, Zhonghao Zhang, Qing Pei
BACKGROUND: Incidences of thyroid cancer (TC) have been increasing worldwide in recent decades. In this research, we aimed to analyze the spatiotemporal pattern of TC and explore relevant environmental risk factors in Hangzhou (HZ), which is rapidly urbanizing and home to the highest TC incidence in China. METHODS: Spatial scan statistic was employed to analyze the spatiotemporal pattern of TC in HZ from 2008 to 2012. The geographically weighted regression model (GWR) was implemented to explore environmental risk factors...
March 3, 2018: Science of the Total Environment
Dorina Murgulet, Melissa Trevino, Audrey Douglas, Nicholas Spalt, Xinping Hu, Valeriu Murgulet
We conducted a comprehensive analysis of a variety of geochemical data including total alkalinity (TA), dissolved inorganic carbon (DIC), dissolved organic carbon (DOC), major ions, stable isotopes, and submarine groundwater discharge, to understand biogeochemical and hydrologic processes driving the seasonal to annual estuarine buffering capacity in Nueces Bay, Texas. These measurements, together with statistical analysis and geochemical modeling, show large variability of freshwater influence. TA consumption, common to spring seasons, was mainly driven by CaCO3 precipitation and, to some extent, by aerobic respiration...
March 3, 2018: Science of the Total Environment
João Castelhano, Paula Tavares, Susana Mouga, Guiomar Oliveira, Miguel Castelo-Branco
OBJECTIVE: Electroencephalographic biomarkers have been widely investigated in autism, in the search for diagnostic, prognostic and therapeutic outcome measures. Here we took advantage of the information available in temporal oscillatory patterns evoked by simple perceptual decisions to investigate whether stimulus dependent oscillatory signatures can be used as potential biomarkers in autism spectrum disorder (ASD). METHODS: We studied an extensive set of stimuli (9 categories of faces) and performed data driven classification (Support vector machine, SVM) of ASD vs...
February 20, 2018: Clinical Neurophysiology: Official Journal of the International Federation of Clinical Neurophysiology
Sung-Wook Yun, Philippe C Baveye, Dong-Hyeon Kim, Dong-Hyeon Kang, Si-Young Lee, Min-Jae Kong, Chan-Gi Park, Hae-Do Kim, Jinkwan Son, Chan Yu
Soil contamination due to atmospheric deposition of metals originating from smelters is a global environmental problem. A common problem associated with this contamination is the discrimination between anthropic and natural contributions to soil metal concentrations: In this context, we investigated the characteristics of soil contamination in the surrounding area of a world class smelter. We attempted to combine several approaches in order to identify sources of metals in soils and to examine contamination characteristics, such as pollution level, range, and spatial distribution...
March 16, 2018: Environmental Pollution
Trajče Stafilov, Robert Šajn, Mila Arapčeska, Ivan Kungulovski, Jasminka Alijagić
The results of the systematic study of the spatial distribution of trace metals in surface soil over the Bitola region, Republic of Macedonia, known for its coal mine and thermo-electrical power plant activities are reported. The investigated region (3200 km2 ) is covered by a sparse sampling grid of 5 × 5 km, but in the urban zone and around the thermoelectric power plant the sampling grid is denser (1 × 1 km). In total, 229 soil samples from 149 locations were collected including top-soil (0-5 cm) and bottom-soil samples (20-30 cm and 0-30 cm)...
March 19, 2018: Journal of Environmental Science and Health. Part A, Toxic/hazardous Substances & Environmental Engineering
Valentine Svensson, Sarah A Teichmann, Oliver Stegle
Technological advances have made it possible to measure spatially resolved gene expression at high throughput. However, methods to analyze these data are not established. Here we describe SpatialDE, a statistical test to identify genes with spatial patterns of expression variation from multiplexed imaging or spatial RNA-sequencing data. SpatialDE also implements 'automatic expression histology', a spatial gene-clustering approach that enables expression-based tissue histology.
March 19, 2018: Nature Methods
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