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dynamic parameters

K Vogt, G Bachmann-Harildstad, A Lintermann, A Nechyporenko, F Peters, K D Wernecke
The report reflects an agreement based on the consensus conference of the International Standardization Committee on the Objective Assessment of the Nasal Airway in Riga, 2nd Nov. 2016. The aim of the conference was to address the existing nasal airway function tests and to take into account physical, mathematical and technical correctness as a base of international standardization as well as the requirements of the Council Directive 93/42/EEC of 14 June 1993 concerning medical devices. Rhinomanometry, acoustic rhinometry, peak nasal inspiratory flow, Odiosoft-Rhino, optical rhinometry, 24-h measurements, computational fluid dynamics, nasometry and the mirrow test were evaluated for important diagnostic criteria, which are the precision of the equipment including calibration and the software applied; validity with sensitivity, specificity, positive and negative predictive values, reliability with intra-individual and inter-individual reproducibility and responsiveness in clinical studies...
January 21, 2018: Rhinology
Monika Kumari, Chi-Hsien Liu, Wei-Chi Wu
Chitosan and its derivatives have shown to be potential gene carriers with biocompatiblility and safety. However, their practical delivery is far from being ideal because of the low transfection efficiency. The present work describes the potential of a natural protein, bovine serum albumin (BSA), conjugated with a natural oligosaccharide, oligochitosan (OC), as a considerable promising approach for a safe and efficient non-viral gene delivery vector. The FTIR spectra proved the effective conjugation of BSA with OC through covalent bond...
March 1, 2018: Carbohydrate Polymers
Jonathan R Mannouch, William Barford, Sarah Al-Assam
The exciton relaxation dynamics of photoexcited electronic states in poly(p-phenylenevinylene) are theoretically investigated within a coarse-grained model, in which both the exciton and nuclear degrees of freedom are treated quantum mechanically. The Frenkel-Holstein Hamiltonian is used to describe the strong exciton-phonon coupling present in the system, while external damping of the internal nuclear degrees of freedom is accounted for by a Lindblad master equation. Numerically, the dynamics are computed using the time evolving block decimation and quantum jump trajectory techniques...
January 21, 2018: Journal of Chemical Physics
Xiukun Li, Lian Wu, Xin Geng, Xiuhong Xia, Xuhong Wang, Zhengjin Xu, Quan Xu
BACKGROUND: Rice (Oryza sativa L.) is cultivated in a wide range of climatic conditions, and is one of mankind's major staple foods. The interaction of environmental factors with genotype effects major agronomic traits such as yield, quality, and resistance in rice. However, studies on the environmental factors affecting agronomic traits are often difficult to conduct because most environmental factors are dynamic and constantly changing. RESULTS: A series of recombinant inbred lines (RILs) derived from an indica/japonica cross were planted into four typical rice cultivated areas arranging from latitude N22° to N42°...
January 19, 2018: Rice
Alexandra Lauric, James E Hippelheuser, Adel M Malek
BACKGROUND: Subtracted 3-D rotational angiography (3DRA) and cone-beam computed tomography angiography (CBCT-A) are often used in assessing cerebral aneurysm shape and haemodynamic profile. We sought to evaluate the effect of imaging modality, reconstruction parameters, and kernel selection on patient-derived aneurysm morphology and computational fluid dynamic (CFD) analysis to assess its potential contribution to inter-study variability. METHODS: Four patients (five aneurysms) underwent concurrent 3DRA followed by high-resolution CBCT-A...
January 19, 2018: Journal of Neurointerventional Surgery
Caspar Schreuer, Stijn Vandewiele, Filip Strubbe, Kristiaan Neyts, Filip Beunis
HYPOTHESIS: Colloidal particles in a pure nonpolar solvent are expected to be in a state of dynamic equilibrium where a particle's charge fluctuates around a stable mean value. However, we find that PHSA-coated PMMA microparticles in dodecane gain positive charge over time. We hypothesize that this phenomenon is prompted by the high electric field (∼1 V/µm) that is applied in these measurements. Hence, we expect the reaction rate at which charge builds up on the particle to change when modifying the measurement parameters...
January 11, 2018: Journal of Colloid and Interface Science
Katherine M Marchetto, Alison G Power
Infections of one host by multiple parasites are common, and several studies have found that the order of parasite invasion can affect both within-host competition and disease severity. However, it is unclear to what extent coinfection timing might be important to consider when modeling parasite impacts on host populations. Using a model system of two viruses infecting barley, we found that simultaneous infections of the two viruses were significantly more damaging to hosts than sequential coinfections. While priority effects were evident in within-host concentrations of sequential coinfections, priority did not influence any parameters (such as virulence or transmission rate) that affect host population dynamics...
February 2018: American Naturalist
Patrick D Ellis Fisher, Qi Shen, Bernice Akpinar, Luke K Davis, Kenny Kwok Hin Chung, David Baddeley, Andela Saric, Thomas J Melia, Bart W Hoogenboom, Chenxiang Lin, C Patrick Lusk
Nuclear pore complexes (NPCs) form gateways that control molecular exchange between the nucleus and the cytoplasm. They impose a diffusion barrier to macromolecules and enable the selective transport of nuclear transport receptors with bound cargo. The underlying mechanisms that establish these permeability properties remain to be fully elucidated, but require unstructured nuclear pore proteins rich in Phe-Gly (FG)-repeat domains of different types, such as FxFG and GLFG. While physical modeling and in vitro approaches have provided a framework for explaining how the FG network contributes to the barrier and transport properties of the NPC, it remains unknown whether the number and/or the spatial positioning of different FG-domains along a cylindrical, ~40 nm diameter transport channel contributes to their collective properties and function...
January 19, 2018: ACS Nano
Zhizhao Che, Omar K Matar
The impact of droplets on liquid films is a ubiquitous phenomenon not only in nature but also in many industrial applications. Compared to the widely-studied impact of droplets on films of identical fluids, the impact of droplets on immiscible films has received far less attention. In the present work, we show using high-speed imaging that immiscibility has a profound effect on the impact dynamics. The impact of a water droplet on an oil film leads to the formation of a compound crown followed by a central jet, whereas that of an oil droplet on a water film results in rapid spreading on the film surface driven by a large, positive spreading factor...
January 19, 2018: Soft Matter
Weida Gong, Hans Paerl, Adrian Marchetti
Over the span of a year, we investigated the interactions between biotic and abiotic factors within the eutrophic Neuse River Estuary (NRE). Through metatranscriptomic sequencing in combination with water quality measurements, we show that there are different metabolic strategies deployed along the NRE. In the upper estuary, taxonomically-resolved phytoplankton groups express more transcripts of genes for synthesis of cellular components and carbon metabolism whereas in the lower estuary, transcripts allocated to nutrient metabolism and transport were more highly expressed...
January 19, 2018: Environmental Microbiology
Wei Wang, Tongqian Zhang
Caspase-1-mediated pyroptosis is the predominance for driving CD4[Formula: see text] T cells death. Dying infected CD4[Formula: see text] T cells can release inflammatory signals which attract more uninfected CD4[Formula: see text] T cells to die. This paper is devoted to developing a diffusive mathematical model which can make useful contributions to understanding caspase-1-mediated pyroptosis by inflammatory cytokines IL-1[Formula: see text] released from infected cells in the within-host environment. The well-posedness of solutions, basic reproduction number, threshold dynamics are investigated for spatially heterogeneous infection...
January 18, 2018: Bulletin of Mathematical Biology
B Mettra, Y Y Liao, T Gallavardin, C Armagnat, D Pitrat, P Baldeck, T Le Bahers, C Monnereau, C Andraud
A large series of structurally related two-photon photosensitizers with heavy atom substitution were synthesized and evaluated through a combined spectroscopic (steady-state and time resolved), photophysical and computational study. Our aim was to identify some relevant parameters related to their excited state dynamics including photo-induced singlet oxygen generation. Although these dynamics result from the interplay of many factors, we show that the triplet excited state generation kinetics can generally be correlated with the calculated values of both the spin-orbit coupling and the energy gap between S1 and T1 states, which themselves mostly depend on the positioning of the heavy atoms along the π-conjugated structure rather than their number...
January 19, 2018: Physical Chemistry Chemical Physics: PCCP
Michael B Dash, Stephen Ajayi, Lynde Folsom, Paul E Gold, Donna L Korol
Extensive trial-to-trial variability is a hallmark of most behavioral, cognitive, and physiological processes. Spontaneous brain activity (SBA), a ubiquitous phenomenon that coordinates levels and patterns of neuronal activity throughout the brain, may contribute to this variability by dynamically altering neuronal excitability. In freely-behaving male rats, we observed extensive variability of the hippocampal evoked response across 28-min recording periods despite maintaining constant stimulation parameters of the medial perforant path...
January 2018: ENeuro
Sebastian Deffner
If a system is driven at finite rate through a phase transition by varying an intensive parameter, the order parameter shatters into finite domains. The Kibble-Zurek mechanism predicts the typical size of these domains, which are governed only by the rate of driving and the spatial and dynamical critical exponents. We show that also the irreversible entropy production fulfills a universal behavior, which however is determined by an additional critical exponent corresponding to the intensive control parameter...
November 2017: Physical Review. E
Glenn C Vidal-Urquiza, Ubaldo M Córdova-Figueroa
The dynamics of a magnetic active Brownian particle undergoing three-dimensional Brownian motion, both translation and rotation, under the influence of a uniform magnetic field is investigated. The particle self-propels at a constant speed along its magnetic dipole moment, which reorients due to the interplay between Brownian and magnetic torques, quantified by the Langevin parameter α. In this work, the time-dependent active diffusivity and the crossover time (τ^{cross})-from ballistic to diffusive regimes-are calculated through the time-dependent correlation function of the fluctuations of the propulsion direction...
November 2017: Physical Review. E
Francisco Vega Reyes, Antonio Lasanta, Andrés Santos, Vicente Garzó
The dynamical properties of a tracer or impurity particle immersed in a host gas of inelastic and rough hard spheres in the homogeneous cooling state is studied. Specifically, the breakdown of energy equipartition as characterized by the tracer/host ratios of translational and rotational temperatures is analyzed by exploring a wide spectrum of values of the control parameters of the system (masses, moments of inertia, sizes, and coefficients of restitution). Three complementary approaches are considered. On the theoretical side, the Boltzmann and Boltzmann-Lorentz equations (both assuming the molecular chaos ansatz) are solved by means of a multitemperature Maxwellian approximation for the velocity distribution functions...
November 2017: Physical Review. E
K N Mukta, J N MacLaurin, P A Robinson
Corticothalamic neural field theory is applied to a spherical geometry to better model neural activity in the human brain and is also compared with planar approximations. The frequency power spectrum, correlation, and coherence functions are computed analytically and numerically. The effects of cortical boundary conditions and resulting modal aspects of spherical corticothalamic dynamics are explored, showing that the results of spherical and finite planar geometries converge to those for the infinite planar geometry in the limit of large brain size...
November 2017: Physical Review. E
R P Linna, P M Suhonen, J Piili
While the dynamics of a fully flexible polymer ejecting a capsid through a nanopore has been extensively studied, the ejection dynamics of semiflexible polymers has not been properly characterized. Here we report results from simulations of ejection dynamics of semiflexible polymers ejecting from spherical capsids. Ejections start from strongly confined polymer conformations of constant initial monomer density. We find that, unlike for fully flexible polymers, for semiflexible polymers the force measured at the pore does not show a direct relation to the instantaneous ejection velocity...
November 2017: Physical Review. E
Na Xu, Kai-Hsin Wu, Shanon J Rubin, Ying-Jer Kao, Anders W Sandvik
We carry out simulated annealing and employ a generalized Kibble-Zurek scaling hypothesis to study the two-dimensional Ising spin glass with normal-distributed couplings. The system has an equilibrium glass transition at temperature T=0. From a scaling analysis when T→0 at different annealing velocities v, we find power-law scaling in the system size for the velocity required in order to relax toward the ground state, v∼L^{-(z+1/ν)}, the Kibble-Zurek ansatz where z is the dynamic critical exponent and ν the previously known correlation-length exponent, ν≈3...
November 2017: Physical Review. E
Bryan Iotti, Alberto Antonioni, Seth Bullock, Christian Darabos, Marco Tomassini, Mario Giacobini
The study of complex networks, and in particular of social networks, has mostly concentrated on relational networks, abstracting the distance between nodes. Spatial networks are, however, extremely relevant in our daily lives, and a large body of research exists to show that the distances between nodes greatly influence the cost and probability of establishing and maintaining a link. A random geometric graph (RGG) is the main type of synthetic network model used to mimic the statistical properties and behavior of many social networks...
November 2017: Physical Review. E
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