bluuebunny/crossref_metadata_2025 huggingface dataset:
Phoneme Categorization in Prelingually Deaf Adult Cochlear Implant Users
Authors: Bochner Joseph , Samar Vincent , Prud'hommeaux Emily , Huenerfauth Matt
Published: October 2022

Purpose:

Phoneme categorization (PC) for voice onset time and second formant transition was studied in adult cochlear implant (CI) users with early-onset deafness and hearing controls.

Method:

Identification and discrimination tasks were administered to 30 participants implanted before 4 years of age, 21 participants implanted after 7 years of age, and 21 hearing individuals.

Results:

Distinctive identification and discrimination functions confirmed PC within all groups. Compared to hearing participants, the CI groups generally displayed longer/higher category boundaries, shallower identification function slopes, reduced identification consistency, and reduced discrimination performance. A principal component analysis revealed that identification consistency, discrimination accuracy, and identification function slope, but not boundary location, loaded on a single factor, reflecting general PC performance. Earlier implantation was associated with better PC performance within the early CI group, but not the late CI group. Within the early CI group, earlier implantation age but not PC performance was associated with better speech recognition. Conversely, within the late CI group, better PC performance but not earlier implantation age was associated with better speech recognition.

Conclusions:

Results suggest that implantation timing within the sensitive period before 4 years of age partly determines the level of PC performance. They also suggest that early implantation may promote development of higher level processes that can compensate for relatively poor PC performance, as can occur in challenging listening conditions.
PVDF–HFP/PZT nanocomposite thin films: preparation, structure and piezoelectric properties
Authors: Oumghar Khadija , Chakhchaoui Nabil , Assal Mohamed , Eddiai Adil , El Achaby Mounir , Meddad Mounir , Cherkaoui Omar , Mazroui M'hamed
Published: October 2022

Piezoelectric nanocomposites have attracted considerable attention from researchers during these last years for their wide use in the development of electromechanical microsystems (MEMS). In this paper, piezoelectric lead titanate zirconate (PZT) are used with poly(vinylidene fluoride-hexafuoropropylene) (PVdF-HFP) polymer matrix to prepare the piezo thin nanocomposite film. An improvement in the β phase in PVdF-HFP was created by the reaction between the PZT nanoparticles and PVdF-HFP. The process used for the preparation of the film results in the enhancement of the ferroelectric and piezoelectric properties of PVdF-HFP. These polymer nanocomposite films were made by the solvent casting method under ultra-sonication using THF as a solvent, with different percentages of PZT. The results confirm that incorporating PZT nanoparticles in the PVDF-HFP matrix increases the β-phase fraction, enhancing the efficiency of energy harvesting.
Grid turbulence studied by Particle Image Velocimetry
Authors: Duda Daniel , Bém Jindřich , Yanovych Vitalii , Uruba Václav
Published: October 2022

We studied the grid-generated turbulence by using Particle Image Velocimetry (PIV) technique. We test on this already well studied flow the new ways of analyzing spatially resolved PIV data, such as the spatial spectra and structure functions. We compare some of the turbulence characteristics with results of Laser Doppler Anemometry (LDA).
Unsteady aerodynamics over surface of a chambered airfoil at stall angle and low Reynolds number
Authors: Genç Gamze , Koca Kemal , Genç Mustafa Serdar
Published: October 2022

The proposal of this paper is clear to reveal and understand the unsteady flow characteristics over the surface of chambered airfoil operating especially at low Reynolds numbers by detecting boundary layer separation and laminar separation bubble (LSB). Experiments including smoke-wire technique for flow visualization, velocity measurement via hot-wire sensor and quasi-wall shear stress measurement by means of the hot-film sensor have been performed over the suction surface of NACA 4412 airfoil at Reynolds number of 5x104 and angle of attack of 14°. Experiments indicate that the airfoil at a stall angle exhibits the bistable characteristics over the suction surface because of the unsteady bubble bursting at low Reynolds numbers. That is, either laminar flow separates from the leading-edge of the airfoil owing to a dominant adverse pressure gradient (APG) or it does not separate along downstream. It is also noted that unsteady boundary layer formation may affect the flow characteristics by changing airfoil’s stability appreciably, causing the periodic fluctuations with the occurring bubble bursting and the leading edge and trailing edge vortex merging. This may conclude undesirable problems such as noise, vibration and flutter for the flight vehicles and wind turbines.
Planar laser-induced fluorescence measurement of the angular pattern of the cone-shaped spray
Authors: Gobyzov Oleg , Ryabov Mikhail , Inzhevatkin Konstantin , Bilsky Artur , Markovich Dmitriy
Published: October 2022

In the present work, a PLIF-based approach for a large cone-shaped spray patternation ispresented and experimental results of its application are discussed. The patternation approach is based on simple time-averaged PLIF imaging. Special attention is paid to the image and data processing in order to simplify a patternation results interpretation. Experimental testing was performed on a water spray, formed by centrifugal nozzle at atmospheric ambient pressure. Circumferential relative concentration profiles in spray crosswise plane are presented in the paper and their validity is analysed.
Development of a two-dimensional mathematical model of flow boiling heat transfer in micro- and minichannels
Authors: Hożejowska Sylwia , Piasecka Magdalena , Piasecki Artur
Published: October 2022

The paper concerns flow boiling heat transfer in micro- and minichannels. In the mathematical model, the steady state heat transfer process in a single asymmetrically heated minichannel was considered. Calculations with the use of Trefftz functions were based on the data from own experiments. The temperature of the heater and the refrigerant were assumed to satisfy the Laplace equations and the energy equation respectively. The problem was solved by the Trefftz method using two sets of Trefftz functions. The known heater and refrigerant temperature distributions were used to determine the heat transfer coefficient at the heater – refrigerant contact. To verify the proposed mathematical model, data from experiments were applied to calculations. The essential part of the experimental stand was the test section which comprises a minichannel heat sink. The heated element for Fluorinert FC-72 flowing along minichannels was a thin foil. The temperature of its outer side was measured using infrared thermography. Thermocouples and pressure transducers installed at the inlet and outlet of the test section monitored fluid temperature and pressure. Mass flow rate, the current supplied to the heater and the voltage drop were also recorded. The resulting graphs presented thermograms of measured temperature on outer surface of the heater, temperature distributions of fluid temperature and local values of the heat transfer coefficient.
Intensification of heat dissipation from electrical elements to closed loop heat pipe
Authors: Lenhard Richard , Kaduchová Katarína , Ďurčanský Peter , Malcho Milan , Kapjor Andrej
Published: October 2022

Article deals with the problem of heat transfer by condenser and evaporator for a closed loop heat pipe for cooling a hermetically sealed electrotechnical box. In an article can by find the design of the heat exchanger for condenser and evaporator for optimal cooling solution, construction and description of experimental state for measuring their performance. Air and heat exchanger temperatures, system pressure, and cooling air flow data were recorded. The measured values are then evaluated and the cooling capacity of the heat exchangers is expressed by means of a sample calculation. The performances are then compared by means of relevant graphs and verified at the end.
A Comparison of Various Images Processing Methods Used in Evaluation of Liquid Film Disruption
Authors: Měšťanová Lucie , Bartoš Ondřej
Published: October 2022

The aim of the paper is to introduce and compare various methods which can be used for an image processing. Studied methods include the image pre-processing and the image segmentation based on the Gaussian mixture model and the active contour. The images are acquired within the measurement of the liquid film disruption on the aerofoil‘s trailing placed edge in the wind tunnel. As the result is suggested sequence of the particular image processing techniques for an optimal result. This work is the part of the wider project devoted to the coarse water droplets which have a negative effect on the steam turbines efficiency and reliability.
In-vitro measurement of aerosol generated by Respimat SMI penetrating through upper airways
Authors: Misik Ondrej , Lizal Frantisek , Malý Milan , Karas Jakub , Jedelsky Jan , Jicha Miroslav
Published: October 2022

Respimat soft mist inhaler (SMI) is an inhaler producing a soft mist with low velocity. The liquid drug solution is emitted by the mechanical energy of compressed spring, so the device is propellant-free. This paper describes the measurement of particle fraction penetrating through the model of the upper respiratory tract (mouth cavity, pharynx, larynx trachea). The solution inside the cartridge was marked by fluorescein in order to evaluate the regional particle deposition in the model. After the exposition, segments of the model, as well as the filter, were washed out and the deposited fluorescein was extracted into water. The analysis showed that the fraction of particles penetrating through the upper respiratory tract was 64.7±6.7 %. However, the real inhalation pattern was not simulated and measurement was provided with continual “inhalation” without “exhalation”.
An experimental investigation on the fluid flow mixing process in agitated vessel
Authors: Młynarczykowska Anna , Ferrari Simone , Demurtas Luana , Jaszczur Marek
Published: October 2022

The fluid mixing process is a common supportive phenomenon that often occurs in a large number of industrial systems. This phenomenon is the subject of many numerical and experimental analysis. The mixing process effectiveness depends on: mixing tank construction, mixing phases viscosity, temperature, density of liquids and, what is crucial, the impeller shape. The optimal design of impeller geometry is still an open issue. In this research work, the main objective is experimental investigations of the influence of the newly constructed impeller type on the fluid flow motion phenomena and energy consumption. Flow field values were evaluated using PIV measurement and the power consumption using precise torquemeter. The comparison between the Rushton turbine and a novel impeller is presented and discussed. The basis for the assessment of the intensity degree and efficiency of mixing was the analysis of velocity vectors distribution and power number. Results show that the power number for both impellers are similar but the fluid motion is quite different. The pumping capacity Qz for the novel impeller in reference to the Rushton turbine is for many cases at least one order of magnitude higher. This shows that the proposed impeller can be a very promising alternative to the classic blades and non-blades based impeller types.
Flow structures stability analysis in a model of a cattle barn using oscillating pattern decomposition method
Authors: Nosek Štěpán , Kluková Zuzana , Kellerová Radka , Jakubcová Michala , Jaňour Zbyněk
Published: October 2022

A model of a cattle barn and a part-depth atmospheric boundary layer were scaled down to 1:50 to simulate the natural ventilation in a wind tunnel. We studied the impact of three opening configurations (entirely, half and quarterly open, which represented 0.7, 0.35 and 0.17 wall porosity, respectively), on the mean flow and the stability of the flow structures in the barn using time-resolved PIV technique and oscillating pattern decomposition method (OPD). While we observed the most-energy-containing structures (POD modes) in the case of the half opening, the most stable structures (OPD modes) correspond to the fully open case. We found that the stability of the structures increases with the opening width (wall porosity), and the highest frequency of these structures was 11 Hz.
On spectral/hp simulations of heat-exchange effects in low-Mach non-stationary fluid flow
Authors: Pech Jan
Published: October 2022

Non-stationary flow of fluid, whose material properties change as influenced by heating, is the subject of this study. Model of coupled Navier-Stokes-Fourier system with temperature dependent material properties is introduced together with construction of appropriate numerical scheme. Spectral/hp element method is used as the discrete approximation of the functions in the spatial coordinates. Performance of the code implemented using Nektar++ library [1] is presented on problems of forced and natural convection around the heated cylinder.
A light sculpture element under wind load – numerical FSI analysis and an experiment in a wind tunnel
Authors: Peukert Pavel , Kult Jaroslav , Rashiwala Hiren , Klouček Pavel , Pomp Norbert , Hochmann Jan , Vomáčko Václav
Published: October 2022

The article introduces a numerical and experimental work to analyse the behaviour of a specific light sculpture element in a wind-load. It starts with a static analysis, which moves to a simplified unsteady analysis followed by a real experiment in a wind channel. The numerical part was not able to provide all necessary information about the light sculpture element behaviour. The experimental part was done to determine the real behaviour of the sculpture element under specified wind conditions.
Using the AQUATOX model to forecast water bodies quality status response to environmental perturbations
Authors: Salvadori Luca , Moccia Davide , Melis Laura , Folegnani Giulia , Pusceddu Antonio , Carucci Alessandra , Ferrari Simone
Published: October 2022

In the last decades, the scientific community has developed many methods and approaches for the assessment of surface waters quality status and the relative impacts of anthropogenic pressures including, among the others, municipal and industrial wastewater treatment plants, agriculture, animal farming and many other land uses. According to the Water Framework Directive (WFD; 2000/60/EC), each EU Member State has been committed to identifying River Basin Districts, in which, ideally, every water body within European boundaries should have been included. As a contribution to the quality assessment of the Sardinian River Basin District, in the framework of the project “Hydraulic and environmental modelling for the gap analysis and the identification of programmes of measures aimed to satisfy the environmental quality objectives” funded by the Regione Sardegna, we applied a simplified version of the AQUATOX model, developed for investigating its feasibility and validity in case of missing or poor input data and information, on the river Cixerri case study.
Experimental investigation of multiphase hydrodynamics of the ocean-atmosphere boundary layer within laboratory modelling
Authors: Sergeev Daniil , Kandaurov Alexander
Published: October 2022

Laboratory modelling of the processes of interaction between the atmosphere and ocean in the boundary layers is one of the most interesting from the point of view of the features of the hydrophysical experiment. The main characteristics that need to be controlled in these experiments include, first of all, the air velocity field over the rough surface waves and the underwater flow, as well as the shape of the free surface. However especial features as spray of droplets, the bubbles in the water and foam generated during the breaking of waves should also be taken into account when modelling extreme weather conditions associated with strong winds. Thus, from the point of view of experimental hydrodynamics, we are dealing with a multiphase turbulent flow with a free boundary. For purpose of experimental study on the wind-wave flume, an integrated approach is required that allows simultaneous measurements of the velocity flow fields, the sizes of droplets and bubbles, the shape of waves and parameters of foam coverage. Contact methods often do not allow for universality. This review study describes developing approaches to the use of optical methods for performing these studies. Presented results were obtained in experiments carried out on several wind-wave flumes. To study the processes of fragmentation of the water surface leading to the formation of droplets an foam, high-speed multi-angle video taking is used in combination with the shadow imaging method.
PIV-system for flow measurements on the benchmark of promising fast neutron nuclear reactor
Authors: Sergeev Daniil , Kandaurov Alexander
Published: October 2022

Carrying out spatio-temporal flow fields parameters is one of the most important and complicated problem within the modeling of heat and hydrophysical processes in operating regimes of the power plants (including nuclear (NPP)). Particle Image Velocimetry (PIV) method (based on the flow visualization, using laser illumination) fits best to satisfy the demands of such measurements. For the experiments on large-scale models of NPP, there is a number of problems in the application of this method, for example, large scales of the flows of the investigated model objects; a noticeable variability of the flow parameters processes with strong temperature fluctuations, leading to optical distortions; necessity of combining imaging and contact gauges probing etc. In this paper we describe PIV- system specifically designed for the study of heat and hydrophysical processes in large-scale model setup of promising fast neutron reactor. The system allows the PIV-measurements for the conditions of complicated configuration of the reactor model, reflections and distortions section of the laser sheet, blackout, in a closed volume. The illumination system using of two lasers and two video cameras with synchronization, allows to obtain an image of the flow in the whole volume of investigation. The use of filtering techniques and method of masks images enabled us to reduce the number of incorrect measurement of flow velocity vectors by an order. The method of conversion of image coordinates and velocity field in the reference model of the reactor using a virtual 3D simulation targets, without loss of accuracy in comparison with a method of using physical objects in filming area was released. The results of measurements of velocity fields in various modes, both stationary (operational), as well as in non-stationary (emergency). These results are compared with measurements of temperature distribution, which were carried out simultaneously. The obtained data set can be used for verifying CFD codes.
Boundary Layer Transition by Advese Pressure Gradient
Authors: Skála Vladislav , Antoš Pavel
Published: October 2022

For some cases of diferrent of boundary layer development conditions (roughness of surface, turbulence in main flow) by adverse pressure gradient was determined tranzitiom region. Boundary layer Tranzition region was found based on intermittency development of flow inside the boundary layer. Intermitency was evaluated using modiffied TERA method algorithm.
Design of air nozzle for air curtains
Authors: Žižkovsky Nikola , Drábek Armand
Published: October 2022

The procedure, which is used in the design of the air nozzle intended to be used on air curtain, is described in this work. The present work is focused on the isolated flow of one air nozzle, while next work will continue with air nozzles constellation. Nozzle reach in the flow field is monitored with and without tangential flow simulating non-isothermal flow. Several basic shapes of nozzles with the same cross-section are evaluated. After searching the design space of the parametric CAD model simulated in isothermal flow – without tangential flow, the best configuration with the longest range were selected. From this smaller set of nozzles was selected one nozzle with the highest directional stability in non-isothermal flow field. The shape of the nozzle with minimal directional deviation in the non-isothermal flow is subsequently optimized by the adjoint method. This method makes it possible to further reduce the pressure loss in the distribution element by deforming the shape according to the local sensitivity of cost function on shape deformation. The final step of design process is to verify effect of modified nozzle on both isothermal and non-isothermal flow filed.
Experimental determination of spatial distribution of granular fractions in flow of bimodal mixture
Authors: Zrostlík Štěpán , Picek Tomáš , Svoboda Lukáš , Matoušek Václav
Published: October 2022

The contribution deals with the determination of the ratio of volumes of particles of individual fractions in flows transporting bimodal granular mixtures. The spatial distribution of the ratio is obtained by analyzing images collected by video recording. The measuring method and post-processing analysis are demonstrated on experiments in our new recirculating fluidization cell. The tested bimodal mixture is composed of two granular fractions of different colors – black and white. The analysis is based on a local identification of particles and their background in the collected images. More precisely, the identification of individual particles is based on the grayscale screening of the images. The method allows to identify both the instantaneous and time-averaged spacious distribution of the grain volume ratio. The experimental results reveal that the measuring method is successful if constant light condition is secured and the medium carrying particles is sufficiently transparent. The method is applicable to laboratory flows with sediment transport no matter whether sediment particles are transported as bed load or as suspended load.
On the global ionospheric diurnal double maxima based on GPS vertical total electron content
Authors: Chen Peng , Wang Rong , Yao Yibin , An Zhiyuan , Wang Zhihao
Published: October 2022

Ionospheric diurnal double maxima (DDM) is a twin-peak pattern in the ionospheric electron density/total electron content (TEC) during the daytime. Understanding the characteristics of DDM is essential to study the physical mechanisms of the ionosphere. In this paper, the vertical TEC data (VTEC) in 2019–2020 derived from 537 globally distributed GPS stations were used to investigate the DDM phenomenon. The results reveal that the occurrence rate of DDMs is roughly quasi-symmetrical about the magnetic equator. In the northern hemisphere, it first increases, then decreases, and finally increases with the increase of magnetic latitude. The DDM phenomenon also exhibits significant seasonal variation. It mainly appears in summer/winter in the northern/southern hemisphere, and the valley and the second peak usually appear earlier in winter and later in summer. According to the difference in the magnitude of the two peaks of DDM, the DDM phenomenon is mainly manifested as the front peak significant type or the posterior peak significant type. The probability of the former shows an M-shaped variation with increasing longitude in the middle and high latitudes of the northern hemisphere and an inverted V-shaped variation in the high latitudes of the southern hemisphere within 180°W~60°W. The probability of the posterior peak significant type shows a trend opposite to the front peak significant type in each area. The occurrence time of DDM structures is usually about one hour later in low-latitude regions than in other regions, and the duration is usually shorter than in other regions. The relative magnitude of the DDM’s twin peaks in low-latitude regions is usually smaller than in other regions.
Echtes Seifenkraut, Saponaria officinalis L.
Authors: Ngo Thu Ha , Melzig MatthiasF.
Published: October 2022

Das Echte Seifenkraut, Saponaria officinalis L., ist eine weit verbreitete
Pflanze, die schon seit der Antike wegen ihrer vielfältigen Wirkungen
therapeutisch und zu Reinigungszwecken eingesetzt wird. Phytotherapeutisch dienen
Saponaria-Drogen wegen ihres Gehaltes an Triterpensaponinen als
Expektorans und Sekretolytikum. Die Saponine wirken auch antimykotisch sowie
immunstimulierend. Daneben induziert das in den Samen der Pflanze vorkommende Lektin
Saporin zytotoxische Effekte und wird gegenwärtig als Bestandteil von
Immunotoxinen in der Krebstherapie eingesetzt.
55 Monate nach regionaler Chemotherapie eines fortgeschrittenen Zungengrundkarzinoms
Authors: Aigner Karl R.
Published: October 2022

Ein 47-jähriger Patient mit einem die mediane Linie überschreitenden Zungengrundkarzinom im Stadium IVA wurde mit insgesamt drei Zyklen intraarterieller Chemotherapie über die linke und rechte A. carotis behandelt. Zur Toxizitätsprophylaxe wurde jeweils eine Chemofiltration im venösen Rückfluss aus dem Tumorareal durchgeführt. Die initial erschwerte orale Nahrungsaufnahme als auch Schmerzen im Stadium 3, waren zum Zeitpunkt der zweiten Therapie nahezu und zu Beginn der dritten Therapie völlig verschwunden. Der Tumor ist seit 55 Monaten in Komplettremission und der Patient völlig beschwerdefrei. Das Prinzip der gesteigerten Tumortoxizität der intraarteriellen Chemotherapie beruht auf der hohen Zytostatikaaufnahme bei der ersten Passage durch die Tumorgefäße.
Fortgeschrittenes Endometriumkarzinom
Authors: Krome Susanne
Published: October 2022

Bei fortschreitenden Endometriumkarzinomen trotz platinbasierter Behandlung ist die Wirksamkeit weiterer Chemotherapien sehr begrenzt. Die 309-KEYNOTE-755-Studie bestätigte die Effektivität einer Kombination aus Tyrosinkinase-Inhibition und Immuncheckpoint-Blockade. Verglichen mit einer aggressiven Chemotherapie waren das progressionsfreie und Gesamtüberleben signifikant verlängert.
Auf Schritt und Tritt – Zur Bedeutung der visuellen
Gangbildanalyse beim Hund
Authors: Zohmann Andreas , Kasper Markus
Published: October 2022

Die Gangbildanalyse (GBA) ist ein wichtiges Werkzeug in der Befundung von
Lahmheiten und der Erkennung von möglichen Schmerzzuständen. Sie
liefert mit dem freien Auge die Möglichkeit, relativ rasch und effizient
Auffälligkeiten zu erkennen und einzuordnen. Was sind die
Voraussetzungen für eine gute Ganganalyse und wie geht man dabei am
besten vor? Welche Rolle spielt die Gangart und wie erkennt und interpretiert
man die häufigsten Störungsmuster? Nicht vergessen werden darf
aber, dass die GBA nur einen Teil der Befundungen im Rahmen des
orthopädisch-physiotherapeutischen Untersuchungsgangs darstellt.
Die wechselvolle Geschichte der Klinik für Dermatologie und Phlebologie im Friedrichshain
Authors: Hermes Barbara , Ludwig-Peitsch Wiebke
Published: October 2022

Der Artikel beschreibt die Geschichte der Hautklinik im Klinikum im Friedrichshain, Berlin von ihren Anfängen 1943 in Berlin-Buch als Ersatz für die zerstörte Hautklinik der Charité bis zur modernen zertifizierten Klinik mit breitem dermatologischen Angebot von heute. Zwischenzeitlich galt es, sowohl politischen Wandel und zwei Umzüge zu bestehen, als auch Schwerpunkte zu setzen und neue Entwicklungen in der Dermatologie in das Klinikspektrum zu integrieren.
Fortgeschrittenes Mammakarzinom
Authors: Arnheim Katharina
Published: October 2022

Antikörper-Drug-Konjugate (ADC) sind eine wichtige Bereicherung für die Therapie des fortgeschrittenen Mammakarzinoms. So hat sich Trastuzumab-Deruxtecan (T-DXd), das beim HER2-positiven Brustkrebs bereits eine hohe Aktivität gezeigt hat, nun auch bei Mammakarzinomen mit geringer HER2-Expression (HER2-low) bewährt. Vielversprechende Daten wurden auf der Jahrestagung der American Society of Clinical Oncology (ASCO) außerdem zu den ADC Sacituzumab Govitecan und Patritumumab-Deruxtecan vorgestellt.
Urologische Tumorentitäten
Authors: Schmale Ine
Published: October 2022

In der Onkologie sind neben der Verfügbarkeit von effektiven und nebenwirkungsarmen Therapieoptionen auch prädiktive und prognostische Marker für die Patientenselektion und Therapieentscheidungen von eminenter Bedeutung. Beim ASCO 2022 wurden für verschiedene urologische Tumorentitäten Studienauswertungen zum besseren Therapiemanagement präsentiert.
Gyrokinetic simulations of turbulence and zonal flows driven by steep profile gradients using a delta-f approach with an evolving background Maxwellian
Authors: Murugappan M. , Villard L. , Brunner S. , McMillan B. F. , Bottino A.
Published: October 2022

Long global gyrokinetic turbulence simulations are particularly challenging in situations where the system deviates strongly from its initial state and when fluctuation levels are high, for example, in strong gradient regions. For particle-in-cell simulations, statistical sampling noise accumulation from large marker weights due to large deviations from the control variate of a delta-f scheme makes such simulations often impractical. An adaptive control variate in the form of a flux-surface-averaged Maxwellian with a time-dependent temperature profile is introduced in an attempt to alleviate the former problem. Under simplified collisionless physics, this adaptive delta-f scheme is shown to reduce noise accumulation in the zonal flows and the simulated heat flux in a quasi-steady turbulent state. The method also avoids the collapse of the signal-to-noise ratio, which occurs in the standard non-adaptive scheme, and, therefore, allows one to reach numerically converged results even with lower marker numbers.
The functions of sleep: A cognitive neuroscience perspective
Authors: Simon Katharine C. , Nadel Lynn , Payne Jessica D.
Published: October 2022

This Special Feature explores the various purposes served by sleep, describing current attempts to understand how the many functions of sleep are instantiated in neural circuits and cognitive structures. Our feature reflects current experts' opinions about, and insights into, the dynamic processes of sleep. In the last few decades, technological advances have supported the updated view that sleep plays an active role in both cognition and health. However, these roles are far from understood. This collection of articles evaluates the dynamic nature of sleep, how it evolves across the lifespan, becomes a competitive arena for memory systems through the influence of the autonomic system, supports the consolidation and integration of new memories, and how lucid dreams might originate. This set of papers highlights new approaches and insights that will lay the groundwork to eventually understand the full range of functions supported by sleep.
The influence of molecular design on structure–property relationships of a supramolecular polymer prodrug
Authors: DeFrates Kelsey G. , Engström Joakim , Sarma Nivedina A. , Umar Athiyya , Shin Jisoo , Cheng Jing , Xie Weiran , Pochan Darrin , Omar Ahmad K. , Messersmith Phillip B.
Published: October 2022

Supramolecular self-assemblies of hydrophilic macromolecules functionalized with hydrophobic, structure-directing components have long been used for drug delivery. In these systems, loading of poorly soluble compounds is typically achieved through physical encapsulation during or after formation of the supramolecular assembly, resulting in low encapsulation efficiencies and limited control over release kinetics, which are predominately governed by diffusion and carrier degradation. To overcome these limitations, amphiphilic prodrugs that leverage a hydrophobic drug as both the therapeutic and structure-directing component can be used to create supramolecular materials with higher loading and controlled-release kinetics using biodegradable or enzymatically cleavable linkers. Here, we report the design, synthesis, and characterization of a library of supramolecular polymer prodrugs based on poly(ethylene glycol) (PEG) and the proregenerative drug 1,4-dihydrophenonthrolin-4-one-3-carboxylic acid (DPCA). Structure–property relationships were elucidated through experimental characterization of prodrug behavior in both the wet and dry states using scattering techniques and electron microscopy and corroborated by coarse-grained modeling. Molecular architecture and the hydrophobic-to-hydrophilic ratio of PEG–DPCA conjugates strongly influenced their physical state in water, ranging from fully soluble to supramolecular spherical assemblies and nanofibers. Molecular design and supramolecular structure, in turn, were shown to dramatically alter hydrolytic and enzymatic release and cellular transport of DPCA. In addition to potentially expanding therapeutic options for DPCA through control of supramolecular assemblies, the design principles elaborated here may inform the development of other supramolecular prodrugs based on hydrophobic small-molecule compounds.
Input integration by the circadian clock exhibits nonadditivity and fold-change detection
Authors: Manella Gal , Bolshette Nityanand , Golik Marina , Asher Gad
Published: October 2022

Circadian clocks are synchronized by external timing cues to align with one another and the environment. Various signaling pathways have been shown to independently reset the phase of the clock. However, in the body, circadian clocks are exposed to a multitude of potential timing cues with complex temporal dynamics, raising the question of how clocks integrate information in response to multiple signals. To investigate different modes of signal integration by the circadian clock, we used Circa-SCOPE, a method we recently developed for high-throughput phase resetting analysis. We found that simultaneous exposure to different combinations of known pharmacological resetting agents elicits a diverse range of responses. Often, the response was nonadditive and could not be readily predicted by the response to the individual signals. For instance, we observed that dexamethasone is dominant over other tested inputs. In the case of signals administered sequentially, the background levels of a signal attenuated subsequent resetting by the same signal, but not by signals acting through a different pathway. This led us to examine whether the circadian clock is sensitive to relative rather than absolute levels of the signal. Importantly, our analysis revealed the involvement of a signal-specific fold-change detection mechanism in the clock response. This mechanism likely stems from properties of the signaling pathway that are upstream to the clock. Overall, our findings elucidate modes of input integration by the circadian clock, with potential relevance to clock resetting under both physiological and pathological conditions.
Definition of a saxitoxin (STX) binding code enables discovery and characterization of the anuran saxiphilin family
Authors: Chen Zhou , Zakrzewska Sandra , Hajare Holly S. , Alvarez-Buylla Aurora , Abderemane-Ali Fayal , Bogan Maximiliana , Ramirez Dave , O’Connell Lauren A. , Du Bois J. , Minor Daniel L.
Published: October 2022

American bullfrog (
Rana castesbeiana
) saxiphilin (
Rc
Sxph) is a high-affinity “toxin sponge” protein thought to prevent intoxication by saxitoxin (STX), a lethal bis-guanidinium neurotoxin that causes paralytic shellfish poisoning (PSP) by blocking voltage-gated sodium channels (Na
V
s). How specific
Rc
Sxph interactions contribute to STX binding has not been defined and whether other organisms have similar proteins is unclear. Here, we use mutagenesis, ligand binding, and structural studies to define the energetic basis of Sxph:STX recognition. The resultant STX “recognition code” enabled engineering of
Rc
Sxph to improve its ability to rescue Na
V
s from STX and facilitated discovery of 10 new frog and toad Sxphs. Definition of the STX binding code and Sxph family expansion among diverse anurans separated by ∼140 My of evolution provides a molecular basis for understanding the roles of toxin sponge proteins in toxin resistance and for developing novel proteins to sense or neutralize STX and related PSP toxins.
Single-beam triaxial spin-exchange relaxation-free atomic magnetometer utilizing transverse modulation fields
Authors: Li Lin , Tang Junjian , Zhao Binbin , Cao Li , Zhou Binquan , Zhai Yueyang
Published: October 2022

We display a single-beam triaxial spin-exchange relaxation-free (SERF) atomic magnetometer by utilizing two orthogonal transverse modulation fields perpendicular to the light. The magnetic field’s three-axis vector components can be extracted simultaneously and independently from the transmitted light by lock-in amplifiers with reference to the different demodulated frequencies. We find that the residual magnetic field is a significant factor that could affect triaxial coupling, and specially the influence of the z-axis remanence on xy-axis coupling is studied in detail. Under the optimal parameters, the three-axis sensitivities are 20 fT Hz

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in the x- and y- axis, and 230 fT Hz

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in the z-axis. Meanwhile, the three-axis bandwidths are 110 Hz, 138 Hz and 211 Hz in the x-, y- and z-axis, respectively. The proposed single-beam triaxial SERF atomic magnetometer could be used to construct a compact and low-cost atomic sensor that is particularly suitable for the vector measurement of the biomagnetic such as magnetoencephalography and magnetocardiography.
Progress on nuclear reaction rates affecting the stellar production of 26Al
Authors: Laird A M , Lugaro M , Kankainen A , Adsley P , Bardayan D W , Brinkman H E , Côté B , Deibel C M , Diehl R , Hammache F , den Hartogh J W , José J , Kurtulgil D , Lederer-Woods C , Lotay G , Meynet G , Palmerini S , Pignatari M , Reifarth R , de Séréville N , Sieverding A , Stancliffe R J , Trueman T C L , Lawson T , Vink J S , Massimi C , Mengoni A
Published: October 2022

The radioisotope 26Al is a key observable for nucleosynthesis in the Galaxy and the environment of the early Solar System. To properly interpret the large variety of astronomical and meteoritic data, it is crucial to understand both the nuclear reactions involved in the production of 26Al in the relevant stellar sites and the physics of such sites. These range from the winds of low- and intermediate-mass asymptotic giant branch stars; to massive and very massive stars, both their Wolf–Rayet winds and their final core-collapse supernovae (CCSN); and the ejecta from novae, the explosions that occur on the surface of a white dwarf accreting material from a stellar companion. Several reactions affect the production of 26Al in these astrophysical objects, including (but not limited to) 25Mg(p, γ)26Al, 26Al(p, γ)27Si, and 26Al(n, p/α). Extensive experimental effort has been spent during recent years to improve our understanding of such key reactions. Here we present a summary of the astrophysical motivation for the study of 26Al, a review of its production in the different stellar sites, and a timely evaluation of the currently available nuclear data. We also provide recommendations for the nuclear input into stellar models and suggest relevant, future experimental work.
Investigations on structural, electronic and optical properties of ZnO in two-dimensional configurations by first-principles calculations
Authors: Wang Hong-Ji , Yang Jun-Tao , Xu Chang-Ju , Huang Hai-Ming , Min Qing , Xiong Yong-Chen , Luo Shi-Jun
Published: October 2022

The electronic structures and optical properties of two-dimensional (2D) ZnO monolayers in a series of configurations were systematically investigated by first-principles calculations with Hubbard U evaluated by the linear response approach. Three types of 2D ZnO monolayers, as planer hexagonal-honeycomb (Plan), double-layer honeycomb (Dlhc), and corrugated tetragonal (Tile) structures, show a mechanical and dynamical stability, while the Dlhc-ZnO is the most energetically stable configuration and Plan-ZnO is the second one. Each 2D ZnO monolayer behaves as a semiconductor with that Plan-, Dlhc-ZnO have a direct band gap of 1.81 eV and 1.85 eV at the Γ point, respectively, while Tile-ZnO has an indirect band gap of 2.03 eV. Interestingly, the 2D ZnO monolayers all show a typical near-free-electron character for the bottom conduction band with a small effective mass, leading to a tremendous optical absorption in the whole visible and ultraviolet window, and this origination was further confirmed by the transition dipole moment. Our investigations suggest a potential candidate in the photoelectric field and provide a theoretical guidance for the exploration of wide-band-gap 2D semiconductors.
Breast tumor detection by 1D-convolutional neural network based on ultra-wide-band microwave technology
Authors: Lu Min , Xiao Xia , Liu Guancong , Lu Hong , Pang Yanwei , Kikkawa Takamaro
Published: October 2022

Ultra-wide band (UWB) microwave is a promising technology for non-invasive detection of breast tumors due to its low cost and the absence of ionizing radiation. However, breast heterogeneity is still the main technical barrier of microwave imaging at present. It is challenging to identify whether there are tumor responses from the detected microwave signals because they contain many high-magnitude skin and fibroglandular scattering signals. To this end, a 1D-convolution neural network (CNN) is proposed to detect the presence of breast tumors directly from raw time-domain microwave signals, avoiding complex microwave image reconstruction and time-consuming feature engineering. The designed network has 10 weight layers; it is composed of a stack of convolution-rectified linear unit-batch normalization layers, and every two stacks are followed by a maxpooling layer. At the end of the network are two fully connected layers to complete the detection task. With the proposed network, the detection accuracies on two datasets simulated by an electromagnetic solver reach 98.20% and 95.97%. The accuracy of experimental verification based on the practical UWB detection system remains good, reaching 94.66%. Finally, through the t-distributed stochastic neighbor embedding technique, the results of feature visualization prove the effectiveness of the trained CNN model. The evaluation results indicate the superior performance of the proposed approach for UWB microwave-based breast tumor detection.
Interface damage monitoring of assembled GFRP-UHPC composite beams using piezoelectric smart aggregate
Authors: Qian Hui , Zhu Yunyun , Liang Penghui , Zhang Pu
Published: October 2022

Glass fiber reinforced plastic reinforcement (GFRP) and ultra-high performance concrete (UHPC) were combined into a new composite beam, which was applied in ocean engineering to improve the durability of structures. To enhance the stiffness and durability of composite beam and lower the cost of structure, prefabricated construction technology was adopted to reserve holes for pouring UHPC. Through the quasi-static test of prefabricated GFRP-UHPC composite beams, the interface between concrete and GFRP was monitored using piezoelectric smart aggregate. The damage index was obtained in accordance with wavelet packet energy analysis theory to examine the interface damage of prefabricated composite beams. Experimental results show that active monitoring of assembled GFRP-UHPC composite beams with piezoelectric smart aggregate can effectively reflect the degree of interface peeling damage of composite beams. The monitoring results reveal that interface damage of specimens with reserved continuous holes is less than that of specimens with reserved discontinuous holes. Moreover, peeling damage will occur not only between GFRP and UHPC, but also at the interface between concrete and UHPC.
Fuel retention and carbon deposition on beryllium marker tiles from JET tokamak main chamber limiters investigated by ion beam analysis
Authors: Tsavalas P. , Lagoyannis A. , Mergia K. , Axiotis M. , Harissopulos S. , Provatas G. , Fazinić S. , Tadić T. , Widdowson A. , Rubel M. , Contributors JET
Published: October 2022

The JET tokamak with the ITER-like wall is operated with arrays of castellated beryllium (Be) limiters in the main chamber. In several locations Be marker tiles were installed for erosion-deposition studies. The castellation sides and the plasma-facing surfaces (PFSs) of Be marker tiles from three different locations of the JET main chamber, from the experimental campaigns 2011–12 (ILW-1) and 2013–14 (ILW-2), were analysed, employing 2H and 3He micro-beams in order to determine carbon (C) impurity deposition and deuterium (D) retention. The deposited C and D amounts on the castellation sides (up to 1.5 mm deep into the groove) were assessed with respect to the ion/electron drift direction. Both the C and D amounts on the investigated castellation sides either stay constant or reduce with depth from the edge of the PFS. No systematic difference is observed in the C deposition or D retention on the different castellation sides of each sample with respect to the ion/electron drift direction. C and D content is found to be lower on the PFS than on surfaces in the gaps of castellation for the majority of the samples. The C amount is, in general, higher than the D one. No systematic correlation between the C and the D amounts has been observed.
Pressure-driven dynamical microfluidic pumping system for droplet production
Authors: Yu Chengzhuang , Wei Chunyang , Li Shanshan , Meng Jiyu , Dai Shijie , Li Junwei
Published: October 2022

Compact and affordable microfluidic pumping is critical for
point-of-care applications. Here we proposed a data driven dynamical
system to build up a pressure-driven microfluidic pump with a small
budget. Firstly, a precision flow sensor is required to obtain the
dynamic flow rates as the responses to the driven pressures. Then
the flow rate dataset under varying operation pressures is used for
data training and model-based system identification. With a
first-order or second-order transfer function model, the
specifications of pressure-driven microfluidic pumping system are
analyzed by the model-based system identification algorithm. Also,
all the specifications including the gain, time constant, natural
frequency, and damping ratio are updated online as new test data are
introduced from more experimental trials. To perform a non-bulky
design purpose, the data training system identification is taken on
a commercial smartphone. Once the training performance is satisfied,
the pressure-driven system could be operated without any flow
sensors. The system is used for two-phase flow controls as a
demonstration, showing a rapid response of pumping. Dynamic
characteristics and the effects of flow resistance on the pumping
performance are analyzed to verify its suitability for a wide range
of microfluidic applications.