bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rauchen in Netflix-Spielfilmen und Jugendschutz
Authors: Hanewinkel Reiner , Neumann Clemens , Morgenstern Matthis 
Published: June 2023

Zusammenfassung
Hintergrund Mit dem Ziel des Jugendschutzes fordert die Weltgesundheitsorganisation, Filme mit Rauchszenen als ungeeignet für Jugendliche einzustufen. Der Konsum von Filmen erfolgt in den letzten Jahren – noch einmal verstärkt durch die COVID-19-Pandemie – zunehmend über Videostreamingdienste, was den Jugendschutz vor neue Herausforderungen stellt.
Fragestellung Die Häufigkeit des Rauchens in Netflix-Spielfilmen sollte erhoben und die Altersempfehlungen für Netflix-Produktionen mit Rauchszenen untersucht werden.
Methode Insgesamt 235 Filme, die in den Jahren 2021 und 2022 exklusiv zum Streaming von der Plattform Netflix bereitgestellt wurden, wurden inhaltsanalysiert. Es wurde betrachtet, (1) wie hoch der Anteil an rauchfreien Filmen in dieser Filmstichprobe war, (2) wie häufig Rauchszenen in diesen Filmen auftraten und (3) wie hoch der Anteil der Filme mit Rauchszenen war, die in Deutschland sowie den USA als für Jugendliche geeignet eingestuft wurden. Als für Kinder und Jugendliche geeignet wurden alle Filme angesehen, deren Altersfreigabe unter 16 Jahren lag.
Ergebnisse In 113 von 235 analysierten Filmen wurde geraucht (48,1%). Von den 113 Filmen mit Rauchszenen wurden in Deutschland 57 (50,4%) und in den USA 26 Filme (23,0%) als jugendfrei eingestuft (p<0,001). 3310 Rauchszenen wurden insgesamt registriert. Davon waren in Deutschland 39,4% (N=1303) in Filmen mit Jugendfreigabe zu sehen, bei Netflix-USA lag dieser Anteil bei 15,8% (N=524).
Diskussion Rauchen tritt in Netflix-Filmen häufig auf. Weder in den USA noch in Deutschland hält sich Netflix an die Empfehlungen des WHO-Rahmenübereinkommens zur Eindämmung des Tabakkonsums, den Zugang von Jugendlichen zu Filmen, in denen das Rauchen dargestellt wird, zuverlässig zu beschränken. Allerdings gelingt der Jugendschutz in den USA im Vergleich zu Deutschland besser, da die Hälfte der Netflix-Filme mit Rauchszenen in Deutschland als jugendgeeignet eingestuft wurden, in den USA weniger als ein Viertel.
Thin films in hydrodynamic lubrication regime: The Osiris friction setup
Authors: Barazzutti Cedric , Cayer-Barrioz Juliette , Mazuyer Denis 
Published: June 2023

A model hydrodynamic lubrication tribometer consisting of two hydrodynamic journal bearings working under thin film conditions was developed to investigate the mechanisms of hydrodynamic friction with low-viscosity fluids and the role of surface effects. A small nominal radial clearance of about 5 µm was considered between the two surfaces. This fully instrumented setup provides in situ information on the sheared fluid film in terms of simultaneous measurements of film thickness; localization and extension of the cavitation zone, with a resolution of 30°; nominal friction torques up to 0.5 N m, with an accuracy of 0.05 mN m; temperature; and the position of the shaft for velocities up to 12 000 rpm. To illustrate the capability of the Osiris tribometer, thin hydrodynamic film measurements were performed on smooth surfaces. The results are presented here, and the thermal effects, acceleration, and inertia contributions are discussed. Finally, the influence of the surface topography using textured surfaces was demonstrated and the role of adsorbed layers on the surface due to fluid formulation was highlighted.
Dynamic and thermodynamic stability of charged perfect fluid stars
Authors: Shi Kai , Tian Yu , Wu Xiaoning , Zhang Hongbao , Zhang Jingchao 
Published: June 2023

Abstract
We perform a thorough analysis of the dynamic and thermodynamic stability for the charged perfect fluid star by applying the Wald formalism to the Lagrangian formulation of Einstein–Maxwell-charged fluid system. As a result, we find that neither the presence of the additional electromagnetic field nor the Lorentz force experienced by the charged fluid makes any obstruction to the key steps towards the previous results obtained for the neutral perfect fluid star. Therefore, the criterion for the dynamic stability of our charged star in dynamic equilibrium within the symplectic complement of the trivial perturbations with the Arnowitt-Deser-Misner (ADM) 3-momentum unchanged is given by the non-negativity of the canonical energy associated with the timelike Killing field, where it is further shown for both non-axisymmetric and axisymmetric perturbations that the dynamic stability against these restricted perturbations also implies the dynamic stability against more generic perturbations. On the other hand, the necessary condition for the thermodynamic stability of our charged star in thermodynamic equilibrium is given by the positivity of the canonical energy of all the linear on-shell perturbations with the ADM angular momentum unchanged in the comoving frame, which is equivalent to the positivity of the canonical energy associated with the timelike Killing field when restricted onto the axisymmetric perturbations. As a by-product, we further establish the equivalence of the dynamic and thermodynamic stability with respect to the spherically symmetric perturbations of the static, spherically symmetric isentropic charged star.
Quasiclassical model of inhomogeneous cosmology
Authors: Bojowald Martin , Hancock Freddy 
Published: June 2023

Abstract
Fluctuation terms and higher moments of a quantum state imply corrections to the classical equations of motion that may have implications in early-Universe cosmology, for instance in the state-dependent form of effective potentials. In addition, space-time properties are relevant in cosmology, in particular when combined with quantum corrections required to maintain general covariance in a consistent way. Here, an extension of previous investigations of static quasiclassical space-time models to dynamical ones is presented, describing the evolution of one-dimensional space as in the classical Lemaitre–Tolman–Bondi models. The corresponding spatial metric has two independent components, both of which are in general subject to quantum fluctuations. The main result is that individual moments from both components are indeed required for general covariance to be maintained at a semiclassical level, while quantum correlations between the components are less relevant.
Optimal readout scheme for multi-degree-of-freedom seismometers
Authors: Peng Xingrui , Martynov Denis , Zhu Zonghong , Miao Haixing 
Published: June 2023

Abstract
The low-frequency performance of advanced gravitational-wave detectors is limited by the seismic noise and the associated control noise. A six-degree-of-freedom seismometer has been proposed in (Mow-Lowry and Martynov 2019 Class. Quantum Grav.
36 245006) to improve the active isolation system. The standard readout scheme, which directly inverts the sensing matrix, gives dynamically independent but not statistically independent estimators for different degrees of freedom. This paper studies the optimal readout scheme by using optimal filters to combine the sensor outputs. The improvement is ultimately limited by the sensor noise and the ground motion, which decreases the correlation. For the real-time implementation, we have considered fitting the optimal filters numerically under the passive and causal constraint.
Pitfalls in applying gravitomagnetism to galactic rotation curve modelling
Authors: Glampedakis Kostas , Jones David Ian 
Published: June 2023

Abstract
The flatness of galaxy rotation curves at large radii is generally considered to be a significant piece of evidence in support of the existence of dark matter. Several studies have claimed that post-Newtonian corrections to the Newtonian equations of galaxy dynamics may remove (at least to some degree) the need for dark matter. A few recent studies have examined these claims, and identified errors in their reasoning. We add to this critique by giving what we consider to be particularly simple and transparent description of the errors made in these post-Newtonian calculations, some of which were of a rather technical nature, others more fundamental, e.g. the loss of the correct relativistic scaling, promoting small corrections to order unity changes. Our work reinforces the orthodoxy that post-Newtonian effects are indeed too small to significantly alter galactic rotation curves, and will hopefully serve as a useful guide for others, pointing out subtle errors that one might inadvertently make in such calculations.
State estimation approach to dual-modal imaging of two-phase flow based on electromagnetic flow tomography and electrical tomography
Authors: Arif M Ziaul , Seppänen Aku , Vauhkonen Marko 
Published: June 2023

Abstract
Monitoring, control and design of industrial processes involving multiphase flows often call for analysis of data from multiple sensors which give information on different quantities of the flowing materials. An example of such case is the problem of monitoring the flow of oil–water mixture: the phase fractions of oil and water, their velocities and volumetric flow rates cannot be retrieved from measurements given by a single sensing/imaging modality. For this reason, multi-modal tomographic imaging systems have been developed. In multi-phase flows, the quantities retrieved from different tomographic instruments are often interconnected—for example, the evolutions of the phase fractions depend on their velocities and vice versa. However, the analysis of data from different tomographic modalities is usually done separately—without taking into account physics that link the quantities of interest. In this paper, we propose a novel approach to image reconstruction in dual-modal tomography of multiphase flows. The governing idea is to combine the two modalities via Bayesian state estimation, that is, we write models that approximate connections between different quantities involved in the process and use sequential measurements from both modalities to jointly estimate these temporally evolving quantities. As an example case, we consider a dual-modal system comprising the electromagnetic flow tomography (EMFT) and electrical tomography (ET). While the EMFT is sensitive to the velocity field but also depends on the phase fractions of fluids, ET measurements are directly linked to phase fractions only. We study the performance of state estimation in EMFT-ET tomography with a set of numerical simulations. The results demonstrate that it outperforms the conventional stationary reconstruction approach, and also provides means for uncertainty quantification in multiphase flow imaging.
Numerical approaches in simulating Trichel pulse characteristics in point-plane configuration
Authors: Shaygani Afshin , Adamiak Kazimierz 
Published: June 2023

Abstract
In this work, a detailed comparison is made of a few different approaches to numerical modeling of non-equilibrium gas discharge plasmas in dry ambient air at atmospheric conditions, leading to Trichel pulse discharge. Simulation models are based on a two-dimensional axisymmetric finite element discretization of point-plane geometry. The negative corona discharge and the hydrodynamic approximation for generic ionic species (electrons, positive and negative ions) are used. The models account for the drift, diffusion, and reactions of the species. They comprise continuity equations coupled to Poisson’s equation for the electric field. Three different formulations were used to specify the ionic reaction rate coefficients. In the first one, the reaction coefficients are approximated by the analytical expressions as a function of the electric field intensity. Two others extract the reaction coefficients from the solution of the Boltzmann equation as a function of the reduced electric field or the electron energy. The effect of gas flow and heating on the pulse characteristics is also investigated. The accuracy of the models has been validated by comparing them with the experimental data.
Controllable spin splitting in 2D ferroelectric few-layer γ-GeSe
Authors: Shi Shuyi , Hao Kuan-Rong , Ma Xing-Yu , Yan Qing-Bo , Su Gang 
Published: June 2023

Abstract

γ-GeSe is a new type of layered bulk material that was recently successfully synthesized. By means of density functional theory first-principles calculations, we systematically studied the physical properties of two-dimensional (2D) few-layer γ-GeSe. It is found that few-layer γ-GeSe are semiconductors with band gaps decreasing with increasing layer number; and 2D γ-GeSe with layer number n ⩾ 2 are ferroelectric with rather low transition barriers, consistent with the sliding ferroelectric mechanism. Particularly, spin–orbit coupling induced spin splitting is observed at the top of valence band, which can be switched by the ferroelectric reversal; furthermore, their negative piezoelectricity also enables the regulation of spin splitting by strain. Finally, excellent optical absorption was also revealed. These intriguing properties make 2D few-layer γ-GeSe promising in spintronic and optoelectric applications.
Kissing the cheeks of Huygens
Authors: Schut Marthe , Schut Paul , Heck André 
Published: June 2023

Abstract
How well do the so-called cheeks of Huygens enforce a constant time of oscillation on a pendulum, independent of the amplitude of the pendulum swing? We use a video measurement tool to test it with a homemade experimental setup that can be fruitfully used in classroom and physics laboratory settings. Data fits reveal how well the setup confirms the usefulness of the cheeks of Huygens. Comparisons of computer model results with recorded data have been made for the same purpose. The equation of motion of a pendulum with a string of arbitrary length that winds along two surfaces of cycloidal cheeks is derived, too. Numerical solutions of this equation are used for the error analysis of measurements with the homemade setup.
Ammonia generation in Ns pulse and Ns pulse/RF discharges over a catalytic surface
Authors: Yang Xin , Richards Caleb , Adamovich Igor V 
Published: June 2023

Abstract
Plasma-catalytic ammonia synthesis in a ns pulse discharge and a ‘hybrid’ ns pulse/RF discharge in plane-to-plane geometry is studied by Fourier Transform infrared absorption spectroscopy. The data are taken in a preheated H2–N2 mixture, with and without Ni/γ-Al2O3 or Co/γ-Al2O3 catalyst placed in the discharge section. The measurement results are taken using two different approaches. The first is a ‘single-stage’ process, where a ns pulse discharge in the H2–N2 mixture is sustained continuously. In this case, the ammonia yield increases slowly, over a period of tens of minutes. The second is a ‘two-stage’ process, where the catalyst is first activated by the ns pulse discharge sustained in pure nitrogen, and then the activated catalyst is exposed to the H2–N2 flow, with or without the discharge. In this case, a strong overshoot of the NH3 number density at the reactor exit is detected, by over a factor of two compared to the single-stage process. After the initial overshoot, the ammonia yield gradually decreases to the ‘single stage’ value (with the discharge on), or to near zero (with the discharge off). The results demonstrate that the ammonia yield in the plasma-catalytic reactor is controlled by the N atom accumulation on the catalyst surface, which reacts with H atoms thermally dissociated on the catalyst or generated in the plasma. The results also show that the plasma-catalytic ammonia yield is significantly higher compared to that in the ns pulse discharge without the catalyst. The accumulation of H atoms on the catalyst, with their subsequent reactions with N atoms generated in the plasma, is of relatively minor importance at the present conditions. An additional series of measurements was made with a sub-breakdown RF waveform overlapped with the ns pulse discharge train, to enhance the vibrational excitation of nitrogen. The ammonia yield measured with the RF waveform added is approximately 20% higher compared to that at the baseline ns pulse discharge conditions, both with and without the catalyst. This effect is weaker compared to that of the catalyst activation by N atoms. Additional data are necessary to isolate the possible effect of the vibrationally excited N2 molecules on the ammonia synthesis in the plasma catalytic reactions.
Multiaxial shape memory effect of thermo-induced shape memory polyurethane under proportional tension-torsion loading
Authors: Liang Zhihong , Li Jian , Chen Kaijuan , Dong Yu , Yu Chao , Kan Qianhua 
Published: June 2023

Abstract
Shape memory behavior of thermo-induced shape memory polyurethane (TSMPU) under proportionally multiaxial loading is investigated experimentally. The shape memory effect is discussed under different axial and torsional loading angles. By comparing the equivalent stress-equivalent strain curves under different loading angles, it is found that the difference in thermo-mechanical behavior is mainly reflected in the shape memory effect. The equivalent characteristic quantities describing the shape memory effect are extracted from the experimental results. By analyzing their evolutions in the strain and stress spaces, it is found that the shape memory effect shows obvious anisotropy under different loading angles, i.e. the equivalent recovery rate of TSMPU increases with the increase of the loading angles. These results are helpful to establish a thermo-mechanical constitutive model for describing the shape memory effect under multiaxial loading.
Contractile and torsional dual-responsive artificial muscles actuated by electric heating and water droplet
Authors: Wang Zeping , Li Qingwei 
Published: June 2023

Abstract
Artificial muscle is a kind of soft actuators that can mimic biological muscles to realize contraction, torsion, and other action modes. Since the artificial muscles based on stimuli-responsive materials can drive the robots to achieve bionic motions under different external stimuli, they are expected to be used in various scenarios. Due to high requirements for the component fibrous materials, the artificial muscles capable of responding to two or more forms of stimuli and integrating multiple functions are rarely reported. Although some valuable attempts (host-guest, sheath-core, hybrid spinning methods) have been made to realize multi-responsive and functional artificial muscles, very complicated and demanding preparation processes are usually needed. Here, we used a direct and effective method to develop dual-responsive artificial muscles without excessive requirements on materials: by plying the viscose and silver-coated nylon coiled yarns (in response to water and electric heating, respectively) into double-helix structure, or tying them into single-strand serial structure, the contractile and torsional muscles can be fabricated readily and conveniently. Under concerted or alternate stimulation of water and electric heating, the dual-responsive muscles can exhibit significant performance improvements (in contractile stroke, output force, durability, etc) and achieve new actuation mode (bidirectional torsion) through the interaction and cooperation of the two component yarns. The moisture detectors based on the dual-responsive muscles were also demonstrated. This work provides a feasible way to prepare dual-/multi-responsive muscles using ordinary stimulus-responsive materials. Besides, the multiple stimuli and the interactions between the muscle components can be fully utilized to improve the muscle performances and extend new functions. These methods and concepts will facilitate the development of multi-responsive and functional artificial muscles, and promote their wide applications.
Experimental entanglement generation using multiport beam splitters
Authors: Kumar Shreya , Bhatti Daniel , Jones Alex E , Barz Stefanie 
Published: June 2023

Abstract
Multipartite entanglement plays a central role in optical quantum technologies. One way to entangle two photons is to prepare them in orthogonal internal states, for example, in two polarisations, and then send them through a balanced beam splitter. Post-selecting on the cases where there is one photon in each output port results in a maximally entangled state. This idea can be extended to schemes for the post-selected generation of larger entangled states. Typically, switching between different types of entangled states requires different arrangements of beam splitters and so a new experimental setup. Here, we demonstrate a simple and versatile scheme to generate different types of genuine tripartite entangled states with only one experimental setup. We send three photons through a three-port splitter and vary their internal states before post-selecting on certain output distributions. This results in the generation of tripartite W, G and GHZ states. We obtain fidelities of up to

(
87.3
±
1.1
)
%

with regard to the respective ideal states, confirming a successful generation of genuine tripartite entanglement.
Helical mode localization and mode locking of ideal MHD instabilities in magnetically perturbed tokamak plasmas
Authors: Puchmayr Jonas , Dunne Mike , Strumberger Erika , Willensdorfer Matthias , Zohm Hartmut , Hindenlang Florian 
Published: June 2023

Abstract
In H-mode tokamak plasmas, the achievable pressure-gradient is limited by type-I Edge Localized Modes (ELMs), which are projected to cause severe damage to future fusion devices. There are several approaches aiming to mitigate/suppress the occurrence of ELMs, such as the application of an external non-axisymmetric magnetic perturbation field, which breaks the axisymmetry of the tokamak plasma. In this work we use the CASTOR3D code to investigate helical localization and mode locking of edge-localized ideal MHD instabilities in rotating and flow-free magnetically perturbed tokamak plasmas with

N
P

=
2

periodicity. Helically localized instabilities are separated into two classes: quasi-locked and strictly locked. In a non-rotating plasma, the localization of quasi-locked modes is determined by an envelope while their precise location under the envelope is arbitrary, whereas strictly locked modes can only occur at a single helical position. Strictly locked modes only rotate if the toroidal plasma rotation exceeds a critical threshold; above the threshold the forced rotation of the strictly locked modes is non-uniform. For quasi-locked modes, no such critical threshold exists; they rotate uniformly beneath their envelope in the case of finite plasma rotation. The helical localization of both quasi-locked and strictly locked instabilities is determined by the energetic decomposition of the instabilities close to the most unstable flux-surface; for example, strongly current-density driven instabilities are aligned with regions of augmented parallel equilibrium current-density. Finally, we compare the computationally determined localization of MHD instabilities to experimental observations. The determined MHD instability is located at the same position as the experimentally measured modes with respect to the equilibrium corrugation, verifying that ideal MHD can describe the experimentally observed instabilities.