bluuebunny/crossref_metadata_2025 huggingface dataset:
Nonequilibrium corrections to gradient flow
Authors: Maes Christian , Netočný Karel
Published: July 2019

The force on a probe induced by a nonequilibrium medium is in general nongradient. We detail the mechanism of this feature via nonequilibrium response theory. The emergence of nongradient forces is due to a systematic “twist” of the excess frenesy with respect to the entropy flux, in response to changes in the coupling or in the position of the probe in the nonequilibrium medium.
The spontaneous breaking of axisymmetry in shallow rotating flows
Authors: Antar G. , Lalti A. , Habchi C.
Published: July 2019

We show that the axial symmetry of a shallow rotating flow is spontaneously broken in the absence of an externally forced velocity gradient. It is caused by an instability excited by the gradients that arise from the axisymmetric counter-rotating vortices. The experimental setup consists of an electrolyte poured into a cylindrical container with radius R and height h and subject to electromagnetic forcing caused by an axial magnetic field and a radial current (J) leading to an azimuthal rotation Vθ. The flow motion is considered to be two-dimensional at large aspect ratio (R/h) and low Reynolds number, Re = Vθh/ν, where ν is the kinematic viscosity. At a moderate aspect ratio, we record the existence of an axisymmetric vortex at the edge caused by the no-slip boundary condition at the walls. When Re is increased by changing h or J, the flow becomes unstable at the radial position where gradients exist due to the edge vortices at a critical Reynolds number of about 220. The most unstable mode of this nonaxisymmetric instability is found to be m = 1 followed by m = 2 and other higher mode numbers. Using perturbation theory, we found that two counter-rotating vortices that are in azimuthal motion are unstable when subject to nonaxisymmetric perturbations with the onset of low azimuthal mode numbers in agreement with the experiment. We conclude that the axial symmetry breaking in shallow rotating flows occurs at relatively low Reynolds numbers caused by the gradients generated by the vortices in the height-radial plane.
Normal mode analysis on the relaxation of an excited nitromethane molecule in argon bath
Authors: Rivera-Rivera Luis A. , Wagner Albert F. , Perry Jamin W.
Published: July 2019

In our previous work [Rivera-Rivera et al., J. Chem. Phys. 142, 014303 (2015)], classical molecular dynamics simulations followed the relaxation, in a 300 K Ar bath at a pressure of 10–400 atm, of nitromethane (CH3NO2) instantaneously excited by statistically distributing 50 kcal/mol among all its internal degrees of freedom. Both rotational and vibrational energies decayed with nonexponential curves. The present work explores mode-specific mechanisms at work in the decay process. With the separation of rotation and vibration developed by Rhee and Kim [J. Chem. Phys. 107, 1394 (1997)], one can show that the vibrational kinetic energy decomposes only into vibrational normal modes, while the rotational and Coriolis energies decompose into both vibrational and rotational normal modes. The saved CH3NO2 positions and momenta were converted into mode-specific energies whose decay was monitored over 1000 ps. The results identify vibrational and rotational modes that promote/resist energy lost and drive nonexponential behavior.
Phase-mixing v.s. phase synchronization in the dynamics of flow-shear induced edge transport barrier
Authors: Leconte M.
Published: July 2019

Nonlinear relaxation oscillations of flow-shear induced transport barriers can be qualitatively reproduced using a phenomenological critical-gradient model [Leconte et al., Contrib. Plasma Phys. 56, 736 (2016)]. Here, we perform a more in-depth analysis of the mechanism of these nonlinear oscillations, associated with nonlinear phase synchronization, in an extended version of the model including random fluctuations.
Passive solar tracker based in the differential thermal expansion of vertical strips
Authors: Brito Miguel Centeno , Pó José Mário , Pereira Daniela , Simões Fernando , Rodriguez Roberto , Amador José Carlos
Published: July 2019

This paper presents a multiple axis passive solar tracking concept that takes advantage of the thermal expansion induced length variation of a material when exposed to sunshine. The differential expansion of three vertical thin flat strips with different orientations is amplified by a lever system to enable tracking of the apparent motion of the sun in the sky. A passive solar tracking system prototype supporting a photovoltaic (PV) module was built and tested. The model and experimental results show that the tracking system can correctly follow the azimuthal motion during the day. The tracking of solar elevation is less pronounced. The use of this tracking system leads to a 28% increase in PV generation during the testing period.
High-throughput microfluidic particle velocimetry using optical time-stretch microscopy
Authors: Ding Yingchun , Yu Liqi , Zhang Chaomin , He Huimei , Zhang Bin , Liu Qiang , Yu Duli , Xing Xiaoxing
Published: July 2019

We report the velocity measurement of microscopic particles flowing at ultrahigh speed with optofluidic time-stretch microscopy at high throughput. This is a study of using optical time-stretch microcopy as a tool for particle velocimetry, where we developed a custom algorithm to process the images acquired from the optofluidic platform for the velocity calculation of individual particles. We experimentally determined the actual flow velocities for polystyrene microspheres with different sizes and traveling through the microchannel at a throughput of ∼10 000 particles/s. We also examined microfluidic channels with different aspect ratios (depth-to-width) for particle velocimetry. The result indicates a measurable flow velocity up to 2.51 m/s. Our method provides a promising tool for label-free and high-throughput particle velocimetry at high velocity magnitudes.
Structure and dynamics of short-chain polymerized ionic liquids
Authors: Wieland F. , Bocharova V. , Münzner P. , Hiller W. , Sakrowski R. , Sternemann C. , Böhmer R. , Sokolov A. P. , Gainaru C.
Published: July 2019

Combining experimental results obtained with X-ray scattering and field-gradient nuclear magnetic resonance (NMR) and an assessment of new and previous dielectric and rheology data, our study focuses on the molecular weight (Mw) evolution of local structure and dynamics in a homologous series of covalently bonded ionic liquids. Performed on a family of electrolytes with a tailored degree of ionic decoupling, this study reveals the differences between monomeric and oligomeric melts with respect to their structural organization, mass and charge transport, and molecular diffusion. Our study demonstrates that for the monomeric compound, the broadband conductivity and mechanical spectra reflect the same underlying distribution of activation barriers and that the Random Barrier Model describes fairly well both the ionic and structural relaxation processes in these materials. Moreover, the oligomers with chains comprising ten segments only exhibit both structural and dynamical fingerprints of a genuine polymer. A comparison of conductivity levels estimated using the self-diffusion coefficients probed via NMR and those probed directly with dielectric spectroscopy reveals the emerging of ion correlations which are affecting the macroscopic charge transport in these materials in a chain-length dependent manner.
Collision of a steepened wave with a blast wave in dusty real reacting gases
Authors: Shah Sarswati , Singh Randheer
Published: July 2019

In this paper, we study the collision of a one-dimensional steepened wave with a blast wave for the system of partial equations describing the unsteady flow of dusty real reacting gases with the same γ-law. The real gas is characterized by a van der Waals type equation of state. Special attention is devoted to analyzing the effects of real, reaction, and dusty gas parameters on the steepened wave. The amplitudes of the reflected and/or transmitted waves along with the jump in shock acceleration after the interaction are also obtained.
Intricate features in the lifetime and deposition of atmospheric aerosol particles
Authors: Haszpra T.
Published: July 2019

The advection of particles emanated, e.g., from volcano eruptions or other pollution events exhibits chaotic behavior in the atmosphere. Due to gravity, the particles move downward on average and remain in the atmosphere for a finite time. The number of particles not yet deposited from the atmosphere decays exponentially after a while characteristic to transient chaos. The so-called escape rate describes the rapidity of the decrease, the reciprocal of which can be used to estimate the average lifetime of the particles. Based on measured wind field data, we follow aerosol particles and demonstrate that the geographical distribution of the individual lifetime of the particles distributed over the globe at different altitudes shows a filamentary, fractal distribution, typical for chaos: the lifetime of particles may be quite different at very nearby geographic locations. These maps can be considered as atlases for the potential fate of volcanic ash clouds or of particles distributed for geoengineering purposes. Particles with similar lifetime deposit also in filamentary structures, but the deposition pattern of extremely long-living particles covers more or less homogeneously the Earth. In general, particles emanated around the equator remain in the atmosphere for the longest time, even for years, e.g., for particles of 1μm radius. The escape rate does not show any considerable dependence on the particles’ initial altitude, indicating that there exists a unique chaotic saddle in the atmosphere. We reconstruct this saddle and its stable and unstable manifolds on two planar slices and follow its time dependence.
Multi-time formulation of Matsubara dynamics
Authors: Jung Kenneth A. , Videla Pablo E. , Batista Victor S.
Published: July 2019

Matsubara dynamics has recently emerged as the most general form of a quantum-Boltzmann-conserving classical dynamics theory for the calculation of single-time correlation functions. Here, we present a generalization of Matsubara dynamics for the evaluation of multitime correlation functions. We first show that the Matsubara approximation can also be used to approximate the two-time symmetrized double Kubo transformed correlation function. By a straightforward extension of these ideas to the multitime realm, a multitime Matsubara dynamics approximation can be obtained for the multitime fully symmetrized Kubo transformed correlation function. Although not a practical method, due to the presence of a phase-term, this multitime formulation of Matsubara dynamics represents a benchmark theory for future development of Boltzmann preserving semiclassical approximations to general higher order multitime correlation functions. It also reveals a connection between imaginary time-ordering in the path integral and the classical dynamics of multitime correlation functions.
Quantification of known and unknown terpenoid organosulfates in PM10 using untargeted LC–HRMS/MS: contrasting summertime rural Germany and the North China Plain
Authors: Brüggemann Martin , van Pinxteren Dominik , Wang Yuchen , Yu Jian Zhen , Herrmann Hartmut
Published: July 2019

Environmental contextSecondary organic aerosols account for a major fraction of atmospheric particulate matter, affecting both climate and human health. Organosulfates, abundant compounds in organic aerosols, are difficult to measure because of the lack of authentic standards. Here we quantify terpene-derived organosulfates in atmospheric particulate matter at a rural site in Germany and at the North China Plain using a combined target/non-target high-resolution mass spectrometry approach.
AbstractOrganosulfates (OSs) are a ubiquitous class of compounds in atmospheric aerosol particles. However, a detailed quantification of OSs is commonly hampered because of missing authentic standards and the abundance of unknown OSs. Using a combined targeted and untargeted approach of high-resolution liquid chromatography–Orbitrap mass spectrometry (LC–Orbitrap MS), we quantified for the first time the total concentrations of known and unknown monoterpene (MT) and sesquiterpene (SQT) OSs in summertime PM10 particulate matter from field studies in rural Germany (MEL) and the North China Plain (NCP). At each site, we observed more than 50 MT-OSs, 13 of which were detectable at both sites. For both locations, median concentrations of MT-OSs were in the range of 10 to 40ngm−3, to which the 13 common MT-OSs contributed on average >50%. The main contributor to MT-OSs was C9H16O7S (MT-OS 267) with average mass concentrations of 2.23 and 6.38ngm−3 for MEL and NCP respectively. The concentrations of MT-OSs correlated with the concentrations of MT oxidation products only for MEL. For NCP, the low concentrations of MT oxidation products (i.e. typically <1ngm−3) suggested a suppression of carboxylic acid formation under high concentrations of NOx and particulate sulfate. Furthermore, we observed 17 SQT-OSs for the MEL samples, whereas 40 SQT-OSs were detected in the NCP samples. Only five of these SQT-OSs were detectable at both sites. Correspondingly, the total concentrations of SQT-OSs were larger for NCP than for MEL, which suggested large differences in the particle chemistry. In particular, aerosol acidity was found to be a key factor during SQT-OS formation, and was probably not sufficient in the PM10 from MEL.
Learning data-driven discretizations for partial differential equations
Authors: Bar-Sinai Yohai , Hoyer Stephan , Hickey Jason , Brenner Michael P.
Published: July 2019

The numerical solution of partial differential equations (PDEs) is challenging because of the need to resolve spatiotemporal features over wide length- and timescales. Often, it is computationally intractable to resolve the finest features in the solution. The only recourse is to use approximate coarse-grained representations, which aim to accurately represent long-wavelength dynamics while properly accounting for unresolved small-scale physics. Deriving such coarse-grained equations is notoriously difficult and often ad hoc. Here we introduce data-driven discretization, a method for learning optimized approximations to PDEs based on actual solutions to the known underlying equations. Our approach uses neural networks to estimate spatial derivatives, which are optimized end to end to best satisfy the equations on a low-resolution grid. The resulting numerical methods are remarkably accurate, allowing us to integrate in time a collection of nonlinear equations in 1 spatial dimension at resolutions 4× to 8× coarser than is possible with standard finite-difference methods.
Variability of signal sequences in turn-taking exchanges induces agency attribution in 10.5-mo-olds
Authors: Tauzin Tibor , Gergely György
Published: July 2019

Significance

We demonstrate that 10.5-mo-old infants—before understanding the symbolic contents encoded by unfamiliar signals—can recognize turn-taking interactions that serve communicative information transmission based on detecting variability in the signal sequences exchanged. Sensitivity to this abstract structural cue is sufficient to attribute communicative abilities and intentional agency to the interacting entities, as indicated by gaze following the agent’s object-oriented turning to fixate its distal referent. When the entities exchanged identical signals only, no gaze following and agency attribution occurred. Infants’ early sensitivity to variability in exchanged signal sequences can play an important role in social-cognitive development and language acquisition by helping infants recognize communicative interactions that can convey relevant information in various pragmatic contexts.
Programmable microencapsulation for enhanced mesenchymal stem cell persistence and immunomodulation
Authors: Mao Angelo S. , Özkale Berna , Shah Nisarg J. , Vining Kyle H. , Descombes Tiphaine , Zhang Liyuan , Tringides Christina M. , Wong Sing-Wan , Shin Jae-Won , Scadden David T. , Weitz David A. , Mooney David J.
Published: July 2019

Significance

Mesenchymal stem cell (MSC) therapies have shown strong preclinical promise, particularly in ameliorating diseases of immune dysregulation. However, these results have largely failed to demonstrate efficacy in clinical settings, likely due to large dosages necessitated by the short residence time of infused cells, suboptimal cell phenotype, and immune rejection. We demonstrate that a microfluidic-based biomaterial encapsulation approach can increase in vivo residence time after intravenous (i.v.) delivery by more than an order of magnitude. Encapsulated cells up-regulated immunomodulatory genes upon exposure to inflammatory cytokines and promoted engraftment of major histocompatibility complex (MHC)-mismatched donor cells in a bone marrow transplant model. The ability to retain i.v. infused MSCs for longer durations may be broadly applicable toward improving MSC therapies.
Development and evolution of age-dependent defenses in ant-acacias
Authors: Leichty Aaron R. , Poethig R. Scott
Published: July 2019

Age-dependent changes in plant defense against herbivores are widespread, but why these changes exist remains a mystery. We explored this question by examining a suite of traits required for the interaction between swollen thorn acacias (genus
Vachellia
) and ants of the genus
Pseudomyrmex
. In this system, plants provide ants with refuge and food in the form of swollen stipular spines, protein-lipid–rich “Beltian” bodies, and sugar-secreting extrafloral nectaries—the “swollen thorn syndrome.” We show that this syndrome develops at a predictable time in shoot development and is tightly associated with the temporal decline in the microRNAs miR156 and miR157 and a corresponding increase in their targets—the SPL transcription factors. Growth under reduced light intensity delays both the decline in miR156/157 and the development of the swollen thorn syndrome, supporting the conclusion that these traits are controlled by the miR156-SPL pathway. Production of extrafloral nectaries by
Vachellia
sp. that do not house ants is also correlated with a decline in miR156/157, suggesting that this syndrome evolved by co-opting a preexisting age-dependent program. Along with genetic evidence from other model systems, these findings support the hypothesis that the age-dependent development of the swollen thorn syndrome is a consequence of genetic regulation rather than a passive developmental pattern arising from developmental constraints on when these traits can develop.
Pleiotropic effects for Parkin and LRRK2 in leprosy type-1 reactions and Parkinson’s disease
Authors: Fava Vinicius M. , Xu Yong Zhong , Lettre Guillaume , Van Thuc Nguyen , Orlova Marianna , Thai Vu Hong , Tao Shao , Croteau Nathalie , Eldeeb Mohamed A. , MacDougall Emma J. , Cambri Geison , Lahiri Ramanuj , Adams Linda , Fon Edward A. , Trempe Jean-François , Cobat Aurélie , Alcaïs Alexandre , Abel Laurent , Schurr Erwin
Published: July 2019

Significance

Type-1 reactions (T1R) are pathological immune responses in leprosy and a frequent cause of peripheral nerve damage. Employing a candidate gene approach combined with deep resequencing, we identified amino acid mutations in the E3 ligase Parkin and the polyfunctional kinase LRRK2 that were associated with T1R. This finding directly linked both proteins with the extent of the immune response in an infectious disease. Moreover, amino acids associated with T1R mutations were significantly enriched for mutations found in patients suffering from Parkinson’s disease (PD). These findings confirm Parkin and LRRK2 as 2 key inflammatory regulators and suggest that T1R and PD share overlapping pathways of pathogenesis.
Nitrogen sourcing during viral infection of marine cyanobacteria
Authors: Waldbauer Jacob R. , Coleman Maureen L. , Rizzo Adriana I. , Campbell Kathryn L. , Lotus John , Zhang Lichun
Published: July 2019

The building blocks of a virus derived from de novo biosynthesis during infection and/or catabolism of preexisting host cell biomass, and the relative contribution of these 2 sources has important consequences for understanding viral biogeochemistry. We determined the uptake of extracellular nitrogen (N) and its biosynthetic incorporation into both virus and host proteins using an isotope-labeling proteomics approach in a model marine cyanobacterium
Synechococcus
WH8102 infected by a lytic cyanophage S-SM1. By supplying dissolved N as
15
N postinfection, we found that proteins in progeny phage particles were composed of up to 41% extracellularly derived N, while proteins of the infected host cell showed almost no isotope incorporation, demonstrating that de novo amino acid synthesis continues during infection and contributes specifically and substantially to phage replication. The source of N for phage protein synthesis shifted over the course of infection from mostly host derived in the early stages to more medium derived later on. We show that the photosystem II reaction center proteins D1 and D2, which are auxiliary metabolic genes (AMGs) in the S-SM1 genome, are made de novo during infection in an apparently light-dependent manner. We also identified a small set of host proteins that continue to be produced during infection; the majority are homologs of AMGs in S-SM1 or other viruses, suggesting selective continuation of host protein production during infection. The continued acquisition of nutrients by the infected cell and their utilization for phage replication are significant for both evolution and biogeochemical impact of viruses.
Defining the Kv2.1–syntaxin molecular interaction identifies a first-in-class small molecule neuroprotectant
Authors: Yeh Chung-Yang , Ye Zhaofeng , Moutal Aubin , Gaur Shivani , Henton Amanda M. , Kouvaros Stylianos , Saloman Jami L. , Hartnett-Scott Karen A. , Tzounopoulos Thanos , Khanna Rajesh , Aizenman Elias , Camacho Carlos J.
Published: July 2019

Significance

An enhanced Kv2.1–syntaxin interaction precedes the neuronal cell death-promoting loss of cytosolic K
+
in many neurodegenerative conditions. The work presented here characterizes the interaction of the disordered C terminus of Kv2.1 to syntaxin at a molecular level and further translates these findings to discover a first-in-class small molecule with neuroprotective properties. In doing so, we demonstrate a rational drug discovery workflow that can elucidate protein–protein interactions involving highly unstructured domains.
Activation loop dynamics are controlled by conformation-selective inhibitors of ERK2
Authors: Pegram Laurel M. , Liddle Jennifer C. , Xiao Yao , Hoh Maria , Rudolph Johannes , Iverson Dylan B. , Vigers Guy P. , Smith Darin , Zhang Hailong , Wang Weiru , Moffat John G. , Ahn Natalie G.
Published: July 2019

Conformational selection by small molecules expands inhibitory possibilities for protein kinases. Nuclear magnetic resonance (NMR) measurements of the mitogen-activated protein (MAP) kinase ERK2 have shown that activation by dual phosphorylation induces global motions involving exchange between two states, L and R. We show that ERK inhibitors Vertex-11e and SCH772984 exploit the small energetic difference between L and R to shift the equilibrium in opposing directions. An X-ray structure of active 2P-ERK2 complexed with AMP-PNP reveals a shift in the Gly-rich loop along with domain closure to position the nucleotide in a more catalytically productive conformation relative to inactive 0P-ERK2:ATP. X-ray structures of 2P-ERK2 complexed with Vertex-11e or GDC-0994 recapitulate this closure, which is blocked in a complex with a SCH772984 analog. Thus, the L→R shift in 2P-ERK2 is associated with movements needed to form a competent active site. Solution measurements by hydrogen-exchange mass spectrometry (HX-MS) reveal distinct binding interactions for Vertex-11e, GDC-0994, and AMP-PNP with active vs. inactive ERK2, where the extent of HX protection correlates with R state formation. Furthermore, Vertex-11e and SCH772984 show opposite effects on HX near the activation loop. Consequently, these inhibitors differentially affect MAP kinase phosphatase activity toward 2P-ERK2. We conclude that global motions in ERK2 reflect conformational changes at the active site that promote productive nucleotide binding and couple with changes at the activation loop to allow control of dephosphorylation by conformationally selective inhibitors.
The E3 ubiquitin ligase Itch restricts antigen-driven B cell responses
Authors: Moser Emily K. , Roof Jennifer , Dybas Joseph M. , Spruce Lynn A. , Seeholzer Steven H. , Cancro Michael P. , Oliver Paula M.
Published: July 2019

The E3 ubiquitin ligase Itch regulates antibody levels and prevents autoimmune disease in humans and mice, yet how Itch regulates B cell fate or function is unknown. We now show that Itch directly limits B cell activity. While Itch-deficient mice displayed normal numbers of preimmune B cell populations, they showed elevated numbers of antigen-experienced B cells. Mixed bone marrow chimeras revealed that Itch acts within B cells to limit naive and, to a greater extent, germinal center (GC) B cell numbers. B cells lacking Itch exhibited increased proliferation, glycolytic capacity, and mTORC1 activation. Moreover, stimulation of these cells in vivo by WT T cells resulted in elevated numbers of GC B cells, PCs, and serum IgG. These results support a novel role for Itch in limiting B cell metabolism and proliferation to suppress antigen-driven B cell responses.
Epistemic Injustice and Psychiatric Classification
Authors: Bueter Anke
Published: July 2019

This article supports calls for an increased integration of patients into taxonomic decision making in psychiatry by arguing that their exclusion constitutes a special kind of epistemic injustice: preemptive testimonial injustice, which precludes the opportunity for testimony due to a wrongly presumed irrelevance or lack of expertise. Here, this presumption is misguided for two reasons: (1) the role of values in psychiatric classification and (2) the potential function of first-person knowledge as a corrective means against implicitly value-laden, inaccurate, or incomplete diagnostic criteria sets. This kind of epistemic injustice leads to preventable epistemic losses in psychiatric classification, diagnosis, and treatment.
Inquiry Tickets: Values, Pursuit, and Underdetermination
Authors: DiMarco Marina , Khalifa Kareem
Published: July 2019

We offer a new account of the role of values in theory choice that captures a temporal dimension to the values themselves. We argue that nonepistemic values sometimes serve as “inquiry tickets,” justifying scientists’ pursuit of certain questions in the short run, while the answers to those questions mitigate transient underdetermination in the long run. Our account of inquiry tickets shows that the role of nonepistemic values need not be restricted to belief or acceptance in order to be relevant to hypothesis choice: the relevance of nonepistemic values to a particular cognitive attitude with respect tohvaries over time.
How to Be a Historically Motivated Antirealist: The Problem of Misleading Evidence
Authors: Frost-Arnold Greg
Published: July 2019

The Pessimistic Induction over the history of science argues that because most past theories judged empirically successful in their time are not even approximately true, most present ones probably are not approximately true either. But why did past scientists accept those incorrect theories? Kyle Stanford’s Problem of Unconceived Alternatives is one answer to that question: scientists are bad at exhausting the space of plausible hypotheses to explain the available evidence. Here, I offer another answer: the Problem of Misleading Evidence. I argue that this proposal enjoys some advantages over Stanford’s, although both are probably needed to explain the historical record.
There Are No Ahistorical Theories of Function
Authors: Garson Justin
Published: July 2019

Theories of function are conventionally divided up into historical and ahistorical ones. Proponents of ahistorical theories often cite the ahistoricity of their accounts as a major virtue. Here, I argue that none of the mainstream “ahistorical” accounts are actually ahistorical. All of them refer, implicitly or explicitly, to history. In Boorse’s goal-contribution account, history is latent in the idea of statistical typicality. In the propensity theory, history is implicit in the idea of a species’ natural habitat. In the causal role theory, history is required for making sense of dysfunction. I elaborate some consequences for the functions debate.
Epistemic Loops and Measurement Realism
Authors: Isaac Alistair M. C.
Published: July 2019

Recent philosophy of measurement has emphasized the existence of both diachronic and synchronic “loops,” or feedback processes, in the epistemic achievements of measurement. A widespread response has been to conclude that measurement outcomes do not convey interest-independent facts about the world and that only a coherentist epistemology of measurement is viable. In contrast, I argue that a form of measurement realism is consistent with these results. The insight is that antecedent structure in measuring spaces constrains our empirical procedures such that successful measurement conveys a limited but veridical knowledge of “fixed points,” or modally stable, interest-independent features of the world.
Multiple Realizability and Biological Modality
Authors: Koskinen Rami
Published: July 2019

Critics of multiple realizability have recently argued that we should concentrate solely on actual here-and-now realizations that are found in nature. The possibility of alternative, but unactualized, realizations is regarded as uninteresting because it is taken to be a question of pure logic or an unverifiable scenario of science fiction. However, in the biological context only a contingent set of realizations is actualized. Drawing on recent work on the theory of neutral biological spaces, the article shows that we can have ways of assessing the modal dimension of multiple realizability that do not have to rely on mere conceivability.
Cubic Auto-Catalysis Reactions in Three-Dimensional Nanofluid Flow Considering Viscous and Joule Dissipations Under Thermal Jump
Authors: Kumar Rakesh , Kumar Ravinder , Koundal Reena , Shehzad Sabir Ali , Sheikholeslami Mohsen
Published: July 2019

In this problem, simultaneous effects of Joule and viscous dissipation in three-dimensional flow of nanoliquid have been addressed in slip flow regime under time dependent rotational oscillations. Silver nanoparticles are submerged in the base fluid (water) due to their chemical and biological features. To increment the novelty, effects of cubic autocatalysis chemical reactions and radiative heat transfer have been incorporated in the related boundary layer equations. Dimensionless partial differential system is solved by employing the proposed implicit finite difference approach. Convergence conditions and stability criteria are obtained to ensure the convergence and accuracy of solutions. A comparative analysis is proposed for no-slip nanofluid flow (NSNF) and slip nanofluid flow (SNF). Variations in skin-friction coefficients, Sherwood and Nusselt numbers against physical parameters are tabulated. It is investigated that velocity slip and temperature jump significantly control drag forces and rate of heat transfer.
Heisenberg-Type Quantum Steering by Continuous Weak Measurement in Circuit QED*
Authors: Wang Zhong
Published: July 2019

Quantum steering has attracted great interest in the last decade, especially in the celebrated optomechanical, cold atom, and quantum optical systems. However, there is still a lack of studies on quantum steering in circuit quantum electrodynamics (QED), which provides a useful experimental platform for revealing novel quantum phenomena. In this work, we investigate the steering of qubit by continuous weak measurement in a circuit QED system and establish a set of multiplicative steering inequalities based on the Heisenberg uncertainty principle. Different from the widely studied systems mentioned above, multiplicative steering inequalities in the circuit QED system are in various forms. We find that only a portion of them can be used to show the detection dependence of the qubit state and we also analyze the reason. Furthermore, we discuss several conditions for the violation of a typical steering inequality, including the measurement strength and methods in detecting the cavity field as well as the quantum efficiency of the detector. This preliminary work could be helpful to quantum steering experiments in circuit QED systems.
A Renormalized-Hamiltonian-Flow Approach to Eigenenergies and Eigenfunctions*
Authors: Wang Wen-Ge
Published: July 2019

We introduce a decimation scheme of constructing renormalized Hamiltonian flows, which is useful in the study of properties of energy eigenfunctions, such as localization, as well as in approximate calculation of eigenenergies. The method is based on a generalized Brillouin-Wigner perturbation theory. Each flow is specific for a given energy and, at each step of the flow, a finite subspace of the Hilbert space is decimated in order to obtain a renormalized Hamiltonian for the next step. Eigenenergies of the original Hamiltonian appear as unstable fixed points of renormalized flows. Numerical illustration of the method is given in the Wigner-band random-matrix model.
Tunable Range Interactions and Multi-Roton Excitations for Bosons in a Bose-Fermi Mixture with Optical Lattices*
Authors: Feng Chao , Chen Yu
Published: July 2019

In this article, we discuss a method to control the long-range interactions between bosons in a three-dimensional Bose-Fermi mixture with the help of optical lattices on fermions. We find the range and the peaked momentum of the fermion-mediated interactions can be tuned by the optical lattice depth and the fermion density. If the fermion density is close to half-filling, roton excitations can be generated with weak Bose-Fermi interactions. Further, if the fermions are not exact at half-filling, multi-roton structure may emerge, implying competing density orders. Therefore, tuning the lattice depth and the fermion density in a Bose-Fermi mixture serves as an effective way to control the interaction range and resonant momentum between bosons.
Three-loop vacuum integral with four-propagators using hypergeometry *
Authors: Gu Zhi-Hua , Zhang Hai-Bin
Published: July 2019

A hypergeometric function is proposed to calculate the scalar integrals of Feynman diagrams. In this study, we verify the equivalence between the Feynman parametrization and the hypergeometric technique for the scalar integral of the three-loop vacuum diagram with four propagators. The result can be described in terms of generalized hypergeometric functions of triple variables. Based on the triple hypergeometric functions, we establish the systems of homogeneous linear partial differential equations (PDEs) satisfied by the scalar integral of three-loop vacuum diagram with four propagators. The continuation of the scalar integral from its convergent regions to entire kinematic domains can be achieved numerically through homogeneous linear PDEs by applying the element method.
The Buchdahl stability bound in Eddington-inspired Born-Infeld gravity *
Authors: Feng Wei-Xiang , Geng Chao-Qiang , Luo Ling-Wei
Published: July 2019

We give the Buchdahl stability bound in Eddington-inspired Born-Infeld (EiBI) gravity. We show that this bound depends on an energy condition controlled by the model parameter

. From this bound, we can constrain

if a neutron star with a mass around

is observed in the future. In addition, to avoid the potential pathologies in EiBI, a Hagedorn-like equation of state associated with

at the center of a compact star is inevitable, which is similar to the Hagedorn temperature in string theory.
Universal scaling of conserved charge in stochastic diffusion dynamics *
Authors: Wu Shanjin , Song Huichao
Published: July 2019

We explore the Kibble-Zurek scaling of conserved charge using stochastic diffusion dynamics. The characteristic scales

and

are determined and used to properly rescale the traditional correlation function and cumulant. We construct universal functions for the two-point correlation

and the second-order cumulant

of the conserved charge in the critical regime, both of which are, near the critical point, insensitive to both the initial temperature and a parameter in the mapping between the 3D Ising model and the hot QCD system.
Influence of the channel length of a vortex tube on the air temperature separation
Authors: Adiullin B R , Mikhaylenko C I
Published: July 2019

A model of a counterflow vortex tube has been prepared to study the dependence of the influence of the tube length parameter on the cold and hot air production. Computational experiments were made using the OpenFOAM package. The prepared grid allowed us to carry out simulations for vortex tubes with lengths of the main channel varying from 20 to 70 cm. All calculations were performed with boundary conditions with constant inlet pressure and atmospheric pressure at the outlet. Results were obtained on temperatures and mass flow rates of the air in the cold and hot outlets of the vortex tube, depending on the length of the device. It is shown that an increase of the length of the vortex tube channel increases the production of cold air. An increase in the temperature of the produced hot air on vortex tube length increase was also noted.
The influence of difference in the surface properties on the axisymmetric oscillations of an oblate drop
Authors: Alabuzhev A A
Published: July 2019

The forced axisymmetric oscillations of an oblate fluid drop are investigated. A drop is cylindrical in equilibrium, surrounded by another liquid and bounded axially by two parallel solid plates. These plates have different surfaces. Hocking’s boundary conditions hold on the contact line: the velocity of the contact line motion is proportional to the deviation of the contact angle from its equilibrium value. The Hocking’s parameter (so-called wetting parameter) is the proportionality coefficient in this case and it is different for each plate. The vibration force is parallel to the symmetry axis of the drop. The solution of the boundary value problem is found using Fourier series of Laplace operator eigen functions.
Control problem for generalized Boussinesq model
Authors: Brizitskii R V , Saritskaya Zh Yu
Published: July 2019

The boundary value and multiplicative control problem for generalized Boussinesq model, in which reaction coefficient has a nonlinear dependence on substances concentration are studied.
Nonlocal strength criteria for the calculation of critical loads in bended structural elements, taking into account the nonlinearity of the material deformation
Authors: Kurguzov V D , Demeshkin A G
Published: July 2019

The destruction of artificial materials (plexiglas, ebonite) in non-uniform stress fields was experimentally investigated. Testing of one batch of samples is carried out using various methods: three-point and clean (four-point) bending of rectangular cross-section beams, Brazilian test (method of splitting a cylinder along a generator). The comparison of the strength characteristics obtained by the Brazilian test with the uniaxial tensile strength, as well as with the tensile strength during bending tests. Experiments on the fracture of beams on a three-point flexural test revealed higher values of ultimate tensile stress than those of a four-point flexural test. The processing of the experimental data obtained by the Brazilian test is carried out using various non-local strength criteria. A sequential analysis of the applicability of the criteria used in the determination of failure loads is carried out. Computer simulation was performed using the finite-element method for the destruction of a cylinder by splitting along a generator, three-point and four-point bending flexural test of a beam in a geometrically nonlinear formulation, taking into account the non-linearity of the material deformation diagram. The problem was solved in the updated Lagrangian formulation taking into account the physical and geometric nonlinearity based on the governing equations of the hypoelastic material. A comparative analysis of the numerical, analytical and experimental results is carried out. A qualitative correspondence was obtained between the experimental data and the results of numerical calculations.
Dependence of tsunami wave maximal heights along a coastline on the source orientation
Authors: Lavrentiev M , Lysakov K , Marchuk An , Oblaukhov K , Shadrin M
Published: July 2019

The authors address an important problem of timely evaluation of tsunami danger after offshore underwater earthquake. In case of Japan it takes nearly 20 minutes for the wave to approach the nearest coast after the seismic event. In this paper we continue to study the influence of tsunami source parameters on the distribution of the wave heights along the coast. As a rule, tsunami wave heights have sharp maximums at selected points of the coast. So, after seismic event the wave may be dangerous only at a few locations. Numerical tests show dependence of the distribution of such maximal wave heights from the orientation of the initial sea bed (sea surface) displacement, which has a form close to reconstruction of historic event at South-East of Japan.
On large-scale quasi-geostrophic dynamical processes in a rotating layer of conducting liquid with arbitrary magnetic Reynolds number
Authors: Peregudin Sergey , Peregudina Elina , Kholodova Svetlana
Published: July 2019

The paper constructs the matheamtical model of dynamics of spatial large-scale quasi-geostrophic motions in a rotating layer of ideal incompressible conducting liquid of variable depth with arbitrary values of the magnetic Reynolds number. Our finding can have certain value in astrophysics and geophysics, for example, in the study of processes occurring in stellar interiors and the liquid Earth core; besides, they can be used in evaluating magnetohydrodynamic characteristics of marine environments, in assessing parameters of wave perturbations sources from the electromagnetic field generated by the corresponding hydrodynamic excitement, which contains important information about geophysical characteristics of the shelf zone. This information is relevant for marine geological surveys and studies.
The evolution of non-linear disturbances in magnetohydrodynamic flows
Authors: Proskurin A V , Sagalakov A M
Published: July 2019

In this article the stability loss of the Hartmann flow are investigated by applying the equations for disturbances. The velocity and electric potential quasi-static MHD model is used. The equations allow us to calculate time-dependent disturbance fields using a base flow and an initial disturbance. Two type of initial perturbations are considered: the eigenfunction of the linearized MHD equations and a fluid injection into the flow. These two approaches lead to identical stability results. However, we found a significant difference in the practical implementation of the two approaches. Dealing with the eigenproblem of the linearized MHD system is a laborious task. In terms of calculation costs it is equal to a series of nonlinear perturbation simulations, and if the Hartmann number is increased, the proportion becomes worse. The non-linear stability analysis produced by these two methods shows that the injection technique can also be used in numerical analysis, and that this method is less expensive in terms of calculation costs.
Simulation of heat and moisture transfer in a porous material
Authors: Fedoseev A V , Salnikov M V , Sukhinin G I
Published: July 2019

The aim of this paper is to present the results of a self-consistent model, which allows describing the evolution of temperature and humidity distributions in a spherical sample of porous clay-like material in drying and cooling processes. Due to the isotropy of the studied material, the solutions obtained are nonlinear radial distributions that change with time. The results are in good agreement with the experimental results obtained in the works of other authors.
Wave phenomena upon interaction between water and high-temperature melt
Authors: Rashkovskiy S A , Yakush S E , Sysoeva E Ya
Published: July 2019

A multiphase model for steam explosion is considered, with assumption of mechanical equilibrium between water and vapor phases in the mixture, but with non-equilibrium drag and heat exchange with high-temperature melt droplets taken into account. Governing equations are formulated and solved numerically. Simulations of pressure waves following thermal interaction of hot melt and water-vapor mixture are presented, the structure of steam explosion wave is discussed.
Addressing Disaster Risk Reduction by Analyzing Sea Level Rise in the Aceh Waters
Authors: Setiawan Ichsan , Ilhamsyah Yopi , Miswar Edy , Irham Muhammad
Published: July 2019

Eustatic changes produce changing on global sea levels, such as changes in water volume in the oceans world. This change indirectly affects the balance of water and land and it is very harmful for the archipelago countries which one of them is Indonesia. The two most important effects are the temperature and mass of water stored on land and sea as fresh water in rivers, lakes, glaciers, polar ice caps, and sea ice. Therefore the purpose of this study is to see how far the sea level changes in Aceh waters in relation to disaster risk reduction. To achieve this goal, the method used is to analyze the record of sea level data in the waters of Aceh during the last 25 years. The analysis of sea surface change data in Aceh shows that there has been a linear increase in sea level since 2008 in parallel with the rise in temperature so that it is expected to lose ground in some areas of the Aceh coast.
Numerical Experiments on Tsunami Wave Forces on Open Structures Using Dam-Break Method
Authors: Syamsidik  , Luthfi Mumtaz , Fauzi Amir , Fatimah Eldina
Published: July 2019

Open wall structures, such as those found in mosques, sustained large forces generated by a tsunami as in the case of the 2004 Indian Ocean tsunami. Although the surrounding buildings were flattened, there were a number of mosques in the tsunami affected area could still stand in the middle of the area. These motivated this study to look into more details the hydrodynamic forces generated around the open structures. This research was aimed at investigating the tsunami wave forces on open structures and at knowing relation between the tsunami waves velocity and the pressures on the pillars of the open structures. DualSPHysic was used to simulate the tsunami wave forces on the structures. The DualSPHysic is a smoothed particle hydrodynamic model with mesh-less method. We simulated 12 numerical simulations by constructing a-130 m wave flume equipped with dam-break at one end to generate the tsunami-like flows. A sloping bed was placed in front of an open wall structure. Four pillars were set to imitate a simplified model of open wall structure. Numerical observation points were placed at offshore part of the model, in front of the pillars (lee-side) and at the back of the pillars (wake-side). Simulations were performed for about 6 seconds started from releasing the dam gate and before the flow being reflected by the other end of the flume. This study proved that the impacts of the tsunami-like forces are more significant of the front row of the pillars. Meanwhile, tsunami wave forces at the back row of the pillars group are inconclusive to the wave velocity and wave heights.