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https://www.readbyqxmd.com/read/28634369/forecasting-effusive-dynamics-and-decompression-rates-by-magmastatic-model-at-open-vent-volcanoes
#1
Maurizio Ripepe, Marco Pistolesi, Diego Coppola, Dario Delle Donne, Riccardo Genco, Giorgio Lacanna, Marco Laiolo, Emanuele Marchetti, Giacomo Ulivieri, Sébastien Valade
Effusive eruptions at open-conduit volcanoes are interpreted as reactions to a disequilibrium induced by the increase in magma supply. By comparing four of the most recent effusive eruptions at Stromboli volcano (Italy), we show how the volumes of lava discharged during each eruption are linearly correlated to the topographic positions of the effusive vents. This correlation cannot be explained by an excess of pressure within a deep magma chamber and raises questions about the actual contributions of deep magma dynamics...
June 20, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28634289/sex-specific-early-survival-drives-adult-sex-ratio-bias-in-snowy-plovers-and-impacts-mating-system-and-population-growth
#2
Luke J Eberhart-Phillips, Clemens Küpper, Tom E X Miller, Medardo Cruz-López, Kathryn H Maher, Natalie Dos Remedios, Martin A Stoffel, Joseph I Hoffman, Oliver Krüger, Tamás Székely
Adult sex ratio (ASR) is a central concept in population biology and a key factor in sexual selection, but why do most demographic models ignore sex biases? Vital rates often vary between the sexes and across life history, but their relative contributions to ASR variation remain poorly understood-an essential step to evaluate sex ratio theories in the wild and inform conservation. Here, we combine structured two-sex population models with individual-based mark-recapture data from an intensively monitored polygamous population of snowy plovers...
June 20, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28633990/cellular-gauge-symmetry-and-the-li-organization-principle-a-mathematical-addendum-quantifying-energetic-dynamics-in-physical-and-biological-systems-through-a-simple-geometric-tool-and-geodetic-curves
#3
REVIEW
Alexander Yurkin, Arturo Tozzi, James F Peters, Pedro C Marijuán
The present Addendum complements the accompanying paper "Cellular Gauge Symmetry and the Li Organization Principle"; it illustrates a recently-developed geometrical physical model able to assess electronic movements and energetic paths in atomic shells. The model describes a multi-level system of circular, wavy and zigzag paths which can be projected onto a horizontal tape. This model ushers in a visual interpretation of the distribution of atomic electrons' energy levels and the corresponding quantum numbers through rather simple tools, such as compasses, rulers and straightforward calculations...
June 17, 2017: Progress in Biophysics and Molecular Biology
https://www.readbyqxmd.com/read/28633970/unified-neural-field-theory-of-brain-dynamics-underlying-oscillations-in-parkinson-s-disease-and-generalized-epilepsies
#4
E J Müller, S J van Albada, J W Kim, P A Robinson
The mechanisms underlying pathologically synchronized neural oscillations in Parkinson's disease (PD) and generalized epilepsies are explored in parallel via a physiologically-based neural field model of the corticothalamic-basal ganglia (CTBG) system. The basal ganglia (BG) are approximated as a single effective population and their roles in the modulation of oscillatory dynamics of the corticothalamic (CT) system and vice versa are analyzed. In addition to normal EEG rhythms, enhanced activity around 4 Hz and 20 Hz exists in the model, consistent with the characteristic frequencies observed in PD...
June 17, 2017: Journal of Theoretical Biology
https://www.readbyqxmd.com/read/28633908/dynamics-of-the-cell-division-orientation-of-granule-cell-precursors-during-cerebellar-development
#5
Satoshi Miyashita, Toma Adachi, Mariko Yamashita, Takayuki Sota, Mikio Hoshino
The cerebellar granule cell (GC) system provides a good model for studying neuronal development. In the external granule layer (EGL), granule cell precursors (GCPs) rapidly and continuously divide to produce numerous GCs as well as GCPs. In some brain regions, the orientation of cell division affects daughter cell fate, thus the direction of GCP division is related to whether it produces a GCP or a GC. Therefore, we tried to characterize the orientation of GCP division from embryonic to postnatal stages and to identify an environmental cue that regulates the orientation...
June 17, 2017: Mechanisms of Development
https://www.readbyqxmd.com/read/28633759/martini-coarse-grained-force-field-extension-to-rna
#6
Jaakko J Uusitalo, Helgi I Ingólfsson, Siewert J Marrink, Ignacio Faustino
RNA has an important role not only as the messenger of genetic information but also as a regulator of gene expression. Given its central role in cell biology, there is significant interest in studying the structural and dynamic behavior of RNA in relation to other biomolecules. Coarse-grain molecular dynamics simulations are a key tool to that end. Here, we have extended the coarse-grain Martini force field to include RNA after our recent extension to DNA. In the same way DNA was modeled, the tertiary structure of RNA is constrained using an elastic network...
June 17, 2017: Biophysical Journal
https://www.readbyqxmd.com/read/28633681/copewell-a-conceptual-framework-and-system-dynamics-model-for-predicting-community-functioning-and-resilience-after-disasters
#7
Jonathan M Links, Brian S Schwartz, Sen Lin, Norma Kanarek, Judith Mitrani-Reiser, Tara Kirk Sell, Crystal R Watson, Doug Ward, Cathy Slemp, Robert Burhans, Kimberly Gill, Tak Igusa, Xilei Zhao, Benigno Aguirre, Joseph Trainor, Joanne Nigg, Thomas Inglesby, Eric Carbone, James M Kendra
OBJECTIVE: Policy-makers and practitioners have a need to assess community resilience in disasters. Prior efforts conflated resilience with community functioning, combined resistance and recovery (the components of resilience), and relied on a static model for what is inherently a dynamic process. We sought to develop linked conceptual and computational models of community functioning and resilience after a disaster. METHODS: We developed a system dynamics computational model that predicts community functioning after a disaster...
June 21, 2017: Disaster Medicine and Public Health Preparedness
https://www.readbyqxmd.com/read/28633567/endogenous-bioelectric-signaling-networks-exploiting-voltage-gradients-for-control-of-growth-and-form
#8
Michael Levin, Giovanni Pezzulo, Joshua M Finkelstein
Living systems exhibit remarkable abilities to self-assemble, regenerate, and remodel complex shapes. How cellular networks construct and repair specific anatomical outcomes is an open question at the heart of the next-generation science of bioengineering. Developmental bioelectricity is an exciting emerging discipline that exploits endogenous bioelectric signaling among many cell types to regulate pattern formation. We provide a brief overview of this field, review recent data in which bioelectricity is used to control patterning in a range of model systems, and describe the molecular tools being used to probe the role of bioelectrics in the dynamic control of complex anatomy...
June 21, 2017: Annual Review of Biomedical Engineering
https://www.readbyqxmd.com/read/28633398/a-novel-system-for-the-treatment-of-aortic-annular-dilation-an-ex-vivo-investigation
#9
Pallav Shah, Claudia Romagnoni, Michal Jaworek, Federico Lucherini, Monica Contino, Alan Menkis, Guido Gelpi, Gianfranco B Fiore, Carlo Antona, Riccardo Vismara
OBJECTIVES: The main reason for aortic repair failures is recurrent annular dilatation. The fibrous portion of left ventricular outflow tract dilates. A novel device was designed to tackle this problem. METHODS: The device consists of an internal ring applied at the aortic annulus plus an external flexible band at the level of the aortic root. The internal ring has a semi-rigid portion (40%, placed at ventriculo-arterial junction) and a flexible portion to allow it to conform along the curves of the non-coronary/right coronary leaflet and right coronary/left coronary leaflet commissures...
June 15, 2017: European Journal of Cardio-thoracic Surgery
https://www.readbyqxmd.com/read/28633194/moving-forward-in-circles-challenges-and-opportunities-in-modelling-population-cycles
#10
REVIEW
Frédéric Barraquand, Stilianos Louca, Karen C Abbott, Christina A Cobbold, Flora Cordoleani, Donald L DeAngelis, Bret D Elderd, Jeremy W Fox, Priscilla Greenwood, Frank M Hilker, Dennis L Murray, Christopher R Stieha, Rachel A Taylor, Kelsey Vitense, Gail S K Wolkowicz, Rebecca C Tyson
Population cycling is a widespread phenomenon, observed across a multitude of taxa in both laboratory and natural conditions. Historically, the theory associated with population cycles was tightly linked to pairwise consumer-resource interactions and studied via deterministic models, but current empirical and theoretical research reveals a much richer basis for ecological cycles. Stochasticity and seasonality can modulate or create cyclic behaviour in non-intuitive ways, the high-dimensionality in ecological systems can profoundly influence cycling, and so can demographic structure and eco-evolutionary dynamics...
June 20, 2017: Ecology Letters
https://www.readbyqxmd.com/read/28632275/architectures-of-soft-robotic-locomotion-enabled-by-simple-mechanical-principles
#11
Liangliang Zhu, Yunteng Cao, Yilun Liu, Zhe Yang, Xi Chen
In nature, a variety of limbless locomotion patterns flourish, from the small or basic life forms (Escherichia coli, amoebae, etc.) to the large or intelligent creatures (e.g., slugs, starfishes, earthworms, octopuses, jellyfishes, and snakes). Many bioinspired soft robots based on locomotion have been developed in the past few decades. In this work, based on the kinematics and dynamics of two representative locomotion modes (i.e., worm-like crawling and snake-like slithering), we propose a broad set of innovative designs for soft mobile robots through simple mechanical principles...
June 20, 2017: Soft Matter
https://www.readbyqxmd.com/read/28632158/on-the-application-of-image-processing-methods-for-bubble-recognition-to-the-study-of-subcooled-flow-boiling-of-water-in-rectangular-channels
#12
Concepción Paz, Marcos Conde, Jacobo Porteiro, Miguel Concheiro
This work introduces the use of machine vision in the massive bubble recognition process, which supports the validation of boiling models involving bubble dynamics, as well as nucleation frequency, active site density and size of the bubbles. The two algorithms presented are meant to be run employing quite standard images of the bubbling process, recorded in general-purpose boiling facilities. The recognition routines are easily adaptable to other facilities if a minimum number of precautions are taken in the setup and in the treatment of the information...
June 20, 2017: Sensors
https://www.readbyqxmd.com/read/28632144/optimal-pitching-axis-location-of-flapping-wings-for-efficient-hovering-flight
#13
Qi Wang, J Goosen, Fred Van Keulen
Flapping wings can pitch passively about their pitching axes due to their flexibility, inertia, and aerodynamic loads. A shift in the pitching axis location can dynamically alter the aerodynamic loads, which in turn changes the passive pitching motion and the flight efficiency. Therefore, it is of great interest to investigate the optimal pitching axis for flapping wings to maximize the power efficiency during hovering flight. In this study, flapping wings are modeled as rigid plates with non-uniform mass distribution...
June 20, 2017: Bioinspiration & Biomimetics
https://www.readbyqxmd.com/read/28631803/a-gompertz-model-approach-to-microbial-inactivation-kinetics-by-high-pressure-processing-hpp-model-selection-and-experimental-validation
#14
Vinicio Serment-Moreno, Claudio Fuentes, José Antonio Torres, Jorge Welti-Chanes
A recently proposed Gompertz model (GMPZ) approach describing microbial inactivation kinetics by high-pressure processing (HPP) incorporated the initial microbial load (N0 ) and lower microbial quantification limit (Nlim ), and simplified the dynamic effects of come-up time (CUT). The inactivation of Listeria innocua in milk by HPP treatments at 300, 400, 500, and 600 MPa and pressure holding times (thold ) ≤10 min was determined experimentally to validate this model approach. Models based on exponential, logistic-exponential, and inverse functions were evaluated to describe the effect of pressure on the lag time (λ) and maximum inactivation rate (μmax ), whereas the asymptote difference (A) was fixed as A = log10 (N0 /Nlim )...
June 20, 2017: Journal of Food Science
https://www.readbyqxmd.com/read/28631792/nanoscopic-dynamics-of-bicontinous-microemulsions-effect-of-membrane-associated-protein
#15
V K Sharma, Douglas G Hayes, Volker S Urban, Hugh M O'Neill, M Tyagi, E Mamontov
Bicontinous microemulsions (BμE) generally consist of nanodomains formed by surfactant in a mixture of water and oil at nearly equal proportions and are potential candidates for the solubilization and purification of membrane proteins. Here we present the first time report of nanoscopic dynamics of surfactant monolayers within BμEs formed by the anionic surfactant sodium dodecyl sulfate (SDS) measured on the nanosecond to picosecond time scale using quasielastic neutron scattering (QENS). BμEs investigated herein consisted of middle phases isolated from Winsor-III microemulsion systems that were formed by mixing aqueous and oil solutions under optimal conditions...
June 20, 2017: Soft Matter
https://www.readbyqxmd.com/read/28631108/reproduction-number-and-asymptotic-stability-for-the-dynamics-of-a-honey-bee-colony-with-continuous-age-structure
#16
M I Betti, L M Wahl, M Zamir
A system of partial differential equations is derived as a model for the dynamics of a honey bee colony with a continuous age distribution, and the system is then extended to include the effects of a simplified infectious disease. In the disease-free case, we analytically derive the equilibrium age distribution within the colony and propose a novel approach for determining the global asymptotic stability of a reduced model. Furthermore, we present a method for determining the basic reproduction number [Formula: see text] of the infection; the method can be applied to other age-structured disease models with interacting susceptible classes...
June 19, 2017: Bulletin of Mathematical Biology
https://www.readbyqxmd.com/read/28630937/high-precision-neural-decoding-of-complex-movement-trajectories-using-recursive-bayesian-estimation-with-dynamic-movement-primitives
#17
Guy Hotson, Ryan J Smith, Adam G Rouse, Marc H Schieber, Nitish V Thakor, Brock A Wester
Brain-machine interfaces (BMIs) are a rapidly progressing technology with the potential to restore function to victims of severe paralysis via neural control of robotic systems. Great strides have been made in directly mapping a user's cortical activity to control of the individual degrees of freedom of robotic end-effectors. While BMIs have yet to achieve the level of reliability desired for widespread clinical use, environmental sensors (e.g. RGB-D cameras for object detection) and prior knowledge of common movement trajectories hold great potential for improving system performance...
July 2016: IEEE Robotics and Automation Letters
https://www.readbyqxmd.com/read/28630676/scaling-properties-of-ageing-orientation-fluctuations-in-stripe-phases
#18
Christian Riesch, Günter Radons, Robert Magerle
We investigate the non-equilibrium dynamics of an ordered stripe-forming system free of topological defects. In particular, we study the ageing and the coarsening of orientation fluctuations parallel and perpendicular to the stripes via computer simulations based on a minimal phase-field model (model B with Coulomb interactions). Under the influence of noise, the stripe orientation field develops fluctuations parallel to the stripes, with the dominant modulation length λ*∥ increasing with time t as λ*∥ ∼ t(1/4) and the correlation length perpendicular to the stripes ξ(⊥)θ increasing as ξ(⊥)θ ∼ t(1/2)...
August 6, 2017: Interface Focus
https://www.readbyqxmd.com/read/28630620/cloud-model-based-artificial-immune-network-for-complex-optimization-problem
#19
Mingan Wang, Shuo Feng, Jianming Li, Zhonghua Li, Yu Xue, Dongliang Guo
This paper proposes an artificial immune network based on cloud model (AINet-CM) for complex function optimization problems. Three key immune operators-cloning, mutation, and suppression-are redesigned with the help of the cloud model. To be specific, an increasing half cloud-based cloning operator is used to adjust the dynamic clone multipliers of antibodies, an asymmetrical cloud-based mutation operator is used to control the adaptive evolution of antibodies, and a normal similarity cloud-based suppressor is used to keep the diversity of the antibody population...
2017: Computational Intelligence and Neuroscience
https://www.readbyqxmd.com/read/28630084/maternal-lifestyle-and-nutritional-status-in-relation-to-pregnancy-and-infant-health-outcomes-in-western-china-protocol-for-a-prospective-cohort-study
#20
Li Tang, Xiong-Fei Pan, Andy H Lee, Colin W Binns, Chun-Xia Yang, Xin Sun
INTRODUCTION: Improving the health and nutrition of women and children is a priority for Western China, where the economy is less developed. Due to the dynamic nature of lifestyle, modern food habits and nutrition, there is a need to update our limited knowledge and understanding of maternal lifestyle and nutritional status and their impact on pregnancy and infant health outcomes. While breast milk is the preferred feeding option, infant formula use is widespread in China. It is thus necessary to examine the effects of formula consumption on growth and morbidity...
June 19, 2017: BMJ Open
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