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https://www.readbyqxmd.com/read/28215003/improved-electromagnetic-tracking-for-catheter-path-reconstruction-with-application-in-high-dose-rate-brachytherapy
#1
Elodie Lugez, Hossein Sadjadi, Chandra P Joshi, Selim G Akl, Gabor Fichtinger
PURPOSE: Electromagnetic (EM) catheter tracking has recently been introduced in order to enable prompt and uncomplicated reconstruction of catheter paths in various clinical interventions. However, EM tracking is prone to measurement errors which can compromise the outcome of the procedure. Minimizing catheter tracking errors is therefore paramount to improve the path reconstruction accuracy. METHODS: An extended Kalman filter (EKF) was employed to combine the nonlinear kinematic model of an EM sensor inside the catheter, with both its position and orientation measurements...
February 18, 2017: International Journal of Computer Assisted Radiology and Surgery
https://www.readbyqxmd.com/read/28213543/functional-characterization-of-a-28-kb-catabolic-island-from-pseudomonas-sp-m1-involved-in-biotransformation-of-%C3%AE-myrcene-and-related-plant-derived-volatiles
#2
Pedro Soares-Castro, Pedro Montenegro-Silva, Hermann J Heipieper, Pedro M Santos
Pseudomonas sp. M1 is able to mineralize highly hydrophobic and recalcitrant compounds such as benzene, phenol and their methylated/halogenated derivatives, as well as the backbone of several monoterpenes. The ability to use such spectrum of compounds as sole carbon source is, most probably, associated with a genetic background evolved under different environmental constraints. The outstanding performance of M1 strain regarding β-myrcene catabolism was elucidated in this work, with focus on the biocatalytical potential of β-myrcene-associated core-code, comprised in a 28-kb genomic island (GI), predicted to be organized in 8 transcriptional units...
February 17, 2017: Applied and Environmental Microbiology
https://www.readbyqxmd.com/read/28213151/automatic-method-for-estimation-of-in-situ-effective-contact-angle-from-x-ray-micro-tomography-images-of-two-phase-flow-in-porous-media
#3
Alessio Scanziani, Kamaljit Singh, Martin J Blunt, Alberto Guadagnini
Multiphase flow in porous media is strongly influenced by the wettability of the system, which affects the arrangement of the interfaces of different phases residing in the pores. We present a method for estimating the effective contact angle, which quantifies the wettability and controls the local capillary pressure within the complex pore space of natural rock samples, based on the physical constraint of constant curvature of the interface between two fluids. This algorithm is able to extract a large number of measurements from a single rock core, resulting in a characteristic distribution of effective in situ contact angle for the system, that is modelled as a truncated Gaussian probability density distribution...
February 8, 2017: Journal of Colloid and Interface Science
https://www.readbyqxmd.com/read/28212848/major-vectors-and-vector-borne-diseases-in-small-ruminants-in-ethiopia-a-systematic-review
#4
REVIEW
Kassahun Asmare, Takele Abayneh, Berhanu Sibhat, Dessie Shiferaw, Barbara Szonyi, Randi I Krontveit, Eystein Skjerve, Barbara Wieland
Vector-borne diseases are among major health constraints of small ruminant in Ethiopia. While various studies on single vector-borne diseases or presence of vectors have been conducted, no summarized evidence is available on the occurrence of these diseases and the related vectors. This systematic literature review provides a comprehensive summary on major vectors and vector-borne diseases in small ruminants in Ethiopia. Search for published and unpublished literature was conducted between 8th of January and 25th of June 2015...
February 14, 2017: Acta Tropica
https://www.readbyqxmd.com/read/28212440/emergent-inequality-and-self-organized-social-classes-in-a-network-of-power-and-frustration
#5
Benoit Mahault, Avadh Saxena, Cristiano Nisoli
We propose a simple agent-based model on a network to conceptualize the allocation of limited wealth among more abundant expectations at the interplay of power, frustration, and initiative. Concepts imported from the statistical physics of frustrated systems in and out of equilibrium allow us to compare subjective measures of frustration and satisfaction to collective measures of fairness in wealth distribution, such as the Lorenz curve and the Gini index. We find that a completely libertarian, law-of-the-jungle setting, where every agent can acquire wealth from or lose wealth to anybody else invariably leads to a complete polarization of the distribution of wealth vs...
2017: PloS One
https://www.readbyqxmd.com/read/28212024/environmental-multi-objective-optimization-of-the-use-of-biomass-resources-for-energy
#6
Carl Vadenbo, Davide Tonini, Thomas Fruergaard Astrup
Bioenergy is often considered an important component, alongside other renewables, to mitigate global warming and to reduce fossil fuel dependency. Determining sustainable strategies for utilizing biomass resources, however, requires a holistic perspective to reflect a wider range of potential environmental consequences. To circumvent the limitations of scenario-based life cycle assessment (LCA), we develop a multi-objective optimization model to systematically identify the environmentally-optimal use of biomass for energy under given system constraints...
February 17, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28211907/identification-of-extracellular-segments-by-mass-spectrometry-improves-topology-prediction-of-transmembrane-proteins
#7
Tamás Langó, Gergely Róna, Éva Hunyadi-Gulyás, Lilla Turiák, Julia Varga, László Dobson, György Várady, László Drahos, Beáta G Vértessy, Katalin F Medzihradszky, Gergely Szakács, Gábor E Tusnády
Transmembrane proteins play crucial role in signaling, ion transport, nutrient uptake, as well as in maintaining the dynamic equilibrium between the internal and external environment of cells. Despite their important biological functions and abundance, less than 2% of all determined structures are transmembrane proteins. Given the persisting technical difficulties associated with high resolution structure determination of transmembrane proteins, additional methods, including computational and experimental techniques remain vital in promoting our understanding of their topologies, 3D structures, functions and interactions...
February 13, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28208766/improved-omnidirectional-odometry-for-a-view-based-mapping-approach
#8
David Valiente, Arturo Gil, Óscar Reinoso, Miguel Juliá, Mathew Holloway
This work presents an improved visual odometry using omnidirectional images. The main purpose is to generate a reliable prior input which enhances the SLAM (Simultaneous Localization and Mapping) estimation tasks within the framework of navigation in mobile robotics, in detriment of the internal odometry data. Generally, standard SLAM approaches extensively use data such as the main prior input to localize the robot. They also tend to consider sensory data acquired with GPSs, lasers or digital cameras, as the more commonly acknowledged to re-estimate the solution...
February 9, 2017: Sensors
https://www.readbyqxmd.com/read/28208453/nonparametric-bayesian-inference-of-the-microcanonical-stochastic-block-model
#9
Tiago P Peixoto
A principled approach to characterize the hidden structure of networks is to formulate generative models and then infer their parameters from data. When the desired structure is composed of modules or "communities," a suitable choice for this task is the stochastic block model (SBM), where nodes are divided into groups, and the placement of edges is conditioned on the group memberships. Here, we present a nonparametric Bayesian method to infer the modular structure of empirical networks, including the number of modules and their hierarchical organization...
January 2017: Physical Review. E
https://www.readbyqxmd.com/read/28208379/prediction-of-the-moments-in-advection-diffusion-lattice-boltzmann-method-i-truncation-dispersion-skewness-and-kurtosis
#10
Irina Ginzburg
The effect of the heterogeneity in the soil structure or the nonuniformity of the velocity field on the modeled resident time distribution (RTD) and breakthrough curves is quantified by their moments. While the first moment provides the effective velocity, the second moment is related to the longitudinal dispersion coefficient (k_{T}) in the developed Taylor regime; the third and fourth moments are characterized by their normalized values skewness (Sk) and kurtosis (Ku), respectively. The purpose of this investigation is to examine the role of the truncation corrections of the numerical scheme in k_{T}, Sk, and Ku because of their interference with the second moment, in the form of the numerical dispersion, and in the higher-order moments, by their definition...
January 2017: Physical Review. E
https://www.readbyqxmd.com/read/28207387/distortion-correction-in-fetal-epi-using-non-rigid-registration-with-a-laplacian-constraint
#11
Maria Kuklisova Murgasova, Georgia Lockwood-Estrin, Rita G Nunes, Shaihan Malik, Mary Rutherford, Daniel Rueckert, Joseph Hajnal
Geometric distortion induced by the main B0 field disrupts the consistency of fetal EPI data, on which diffusion and functional MRI is based. In this paper we present a novel data-driven method for simultaneous motion and distortion correction of fetal EPI. A motion-corrected and reconstructed T2 weighted ssFSE volume is used as a model of undistorted fetal brain anatomy. Our algorithm interleaves two registration steps: estimation of fetal motion parameters by aligning EPI slices to the model; and deformable registration of EPI slices to slices simulated from the undistorted model to estimate the distortion field...
February 9, 2017: IEEE Transactions on Medical Imaging
https://www.readbyqxmd.com/read/28207296/gambit-a-parameterless-model-based-evolutionary-algorithm-for-mixed-integer-problems
#12
Krzysztof L Sadowski, Dirk Thierens, Peter A N Bosman
Learning and exploiting problem structure is one of the key challenges in optimization. This is especially important for black-box optimization (BBO) where prior structural knowledge of a problem is not available. Existing model-based Evolutionary Algorithms (EAs) are very efficient at learning structure in both the discrete, and in the continuous domain. In this paper, discrete and continuous model-building mechanisms are integrated for the Mixed-Integer (MI) domain, comprising discrete and continuous variables...
February 16, 2017: Evolutionary Computation
https://www.readbyqxmd.com/read/28202479/improving-services-for-glaucoma-care-in-nigeria-implications-for-policy-and-programmes-to-achieve-universal-health-coverage
#13
Fatima Kyari, Clare Gilbert, Karl Blanchet, Richard Wormald
Glaucoma in Africa is sometimes referred to as the silent thief of sight. In Nigeria, glaucoma is common, it is serious, ophthalmologists face many constraints in managing it, people do not even know they have it until it is advanced, patients do not understand or comply with treatment after they are diagnosed and the poor are more likely to be glaucoma blind. Available evidence indicates that the health system in Nigeria is failing to meet the needs of patients with glaucoma. Based on evidence, we propose future directions for improving services for glaucoma care in Nigeria, and the implications for policy and programmes to control glaucoma blindness, using a health system-oriented approach...
February 15, 2017: British Journal of Ophthalmology
https://www.readbyqxmd.com/read/28199327/spatial-gender-age-period-cohort-analysis-of-pancreatic-cancer-mortality-in-spain-1990-2013
#14
Jaione Etxeberria, Tomás Goicoa, Gonzalo López-Abente, Andrea Riebler, María Dolores Ugarte
Recently, the interest in studying pancreatic cancer mortality has increased due to its high lethality. In this work a detailed analysis of pancreatic cancer mortality in Spanish provinces was performed using recent data. A set of multivariate spatial gender-age-period-cohort models was considered to look for potential candidates to analyze pancreatic cancer mortality rates. The selected model combines features of APC (age-period-cohort) models with disease mapping approaches. To ensure model identifiability sum-to-zero constraints were applied...
2017: PloS One
https://www.readbyqxmd.com/read/28195015/the-effect-of-catastrophic-health-expenditure-on-work-after-retirement
#15
Enayatollah Homaie Rad, Arash Rashidian, Mohamad Arab, Ali Souri
Several factors can force retirees to go to paid work. Catastrophic health-care expenditure (CHCE) is one of the driving forces for retirees to go to paid work. This cross-sectional study was based on 6,307 Iran retirees' data. Xu method was used to calculate CHCE, and a logit model was estimated to show the association between CHCE and bridge employment. Other control variables were added to the model. The findings showed that there was positive relationship between CHCE and bridge employment. Retirement pension had negative relationship with work after retirement...
March 2017: International Journal of Aging & Human Development
https://www.readbyqxmd.com/read/28194230/what-are-the-personal-and-professional-characteristics-that-distinguish-the-researchers-who-publish-in-high-and-low-impact-journals-a-multi-national-web-based-survey
#16
Carlos Eduardo Paiva, Raphael L C Araujo, Bianca Sakamoto Ribeiro Paiva, Cristiano de Pádua Souza, Flavio Mavignier Cárcano, Marina Moreira Costa, Sérgio Vicente Serrano, João Paulo Nogueira Lima
PURPOSE: This study identifies the personal and professional profiles of researchers with a greater potential to publish high-impact academic articles. METHOD: The study involved conducting an international survey of journal authors using a web-based questionnaire. The survey examined personal characteristics, funding, and the perceived barriers of research quality, work-life balance, and satisfaction and motivation in relation to career. The processes of manuscript writing and journal publication were measured using an online questionnaire that was developed for this study...
2017: Ecancermedicalscience
https://www.readbyqxmd.com/read/28188985/3d-ssf-a-bio-inspired-approach-for-dynamic-multi-subject-clustering-of-white-matter-tracts
#17
REVIEW
A Chekir, S Hassas, M Descoteaux, M Côté, E Garyfallidis, F Oulebsir-Boumghar
There is growing interest in the study of white matter (WM) variation across subjects, and in particular the analysis of specific WM bundles, to better understand brain development and aging, as well as to improve early detection of some diseases. Several WM multi-subject clustering methods have been proposed to study WM bundles. These methods aim to overcome the complexity of the problem, which includes the huge size of the WM tractography datasets generated from multiple subjects, the existence of various streamlines with different positions, lengths and geometric forms, as well as the presence of outliers...
January 27, 2017: Computers in Biology and Medicine
https://www.readbyqxmd.com/read/28187353/towards-an-ecologically-grounded-functional-practice-in-rehabilitation
#18
Daniela Virgínia Vaz, Paula Lanna Silva, Marisa Cotta Mancini, Claudia Carello, Jeffrey Kinsella-Shaw
According to the International Classification of Functioning, Disability and Health, effective rehabilitation requires interventions that go beyond minimizing pathological conditions and associated symptoms. The scope of practice must include promoting an individual's activity within relevant contexts. We argue that best practice requires decisions that are not only evidence-based but also theory-based. Perception and action theories are essential for interpreting evidence and clinical phenomena as well as for developing new interventions...
February 7, 2017: Human Movement Science
https://www.readbyqxmd.com/read/28187207/a-multi-objective-constraint-based-approach-for-modeling-genome-scale-microbial-ecosystems
#19
Marko Budinich, Jérémie Bourdon, Abdelhalim Larhlimi, Damien Eveillard
Interplay within microbial communities impacts ecosystems on several scales, and elucidation of the consequent effects is a difficult task in ecology. In particular, the integration of genome-scale data within quantitative models of microbial ecosystems remains elusive. This study advocates the use of constraint-based modeling to build predictive models from recent high-resolution -omics datasets. Following recent studies that have demonstrated the accuracy of constraint-based models (CBMs) for simulating single-strain metabolic networks, we sought to study microbial ecosystems as a combination of single-strain metabolic networks that exchange nutrients...
2017: PloS One
https://www.readbyqxmd.com/read/28186796/from-planck-data-to-planck-era-observational-tests-of-holographic-cosmology
#20
Niayesh Afshordi, Claudio Corianò, Luigi Delle Rose, Elizabeth Gould, Kostas Skenderis
We test a class of holographic models for the very early Universe against cosmological observations and find that they are competitive to the standard cold dark matter model with a cosmological constant (ΛCDM) of cosmology. These models are based on three-dimensional perturbative superrenormalizable quantum field theory (QFT), and, while they predict a different power spectrum from the standard power law used in ΛCDM, they still provide an excellent fit to the data (within their regime of validity). By comparing the Bayesian evidence for the models, we find that ΛCDM does a better job globally, while the holographic models provide a (marginally) better fit to the data without very low multipoles (i...
January 27, 2017: Physical Review Letters
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