bluuebunny/crossref_metadata_2025 huggingface dataset:
Die Bedeutung von Zertifikaten im Krankenhaus
Authors: Sarbandi Michael
Published: July 2024

Was bewegt Krankenhäuser trotz Aufwand und Kosten sich zertifizieren zu lassen?
Welchen Mehrwert gibt es für die Krankenhäuser durch Zertifizierungsprozesse? In
einer Online-Umfrage wurden Qualitätsbeauftragte aus 188 Krankenhäusern gebeten,
ihre Einschätzung zur Qualität und der Bedeutung von externen
Zertifizierungsprozessen im Krankenhaus zu geben. Die Resultate zeigen, dass die
Bereitschaft, QM-Systeme oder eine spezialisierte Arbeit in Versorgungszentren
zertifizieren zu lassen, bei den Krankenhäusern hoch ist, obwohl die wachsende
Zahl von Zertifizierungsangeboten und Qualitätslabels bei Patient*innen
möglicherweise zu Unsicherheit und Verwirrung führt, zumal die Bedeutung der
Zertifikate häufig nicht klar ist, und die normativen Regelwerke und
Kriterienkataloge oft nicht zugänglich sind.
Progressive Muscle Relaxation Training During Pregnancy: Effects on Mental State, Delivery and Labour Pain – a Prospective Study
Authors: Weschenfelder Friederike , Bulgay-Mörschel Mehtap , Lütje Wolf , Schleußner Ekkehard
Published: July 2024

Progressive muscle relaxation is a widely used technique for relaxation, but studies are rare about efficacy on pregnancy and perinatal outcomes. Aim of our study was to determine whether progressive muscle relaxation affects anxiety and depression levels of pregnant women, pregnancy outcomes, labour pain and analgesic requirements.

156 pregnant women were enrolled in a prospective non-randomized controlled cohort study. The control group received standard antenatal care and classes only, while the intervention group additionally received progressive muscle relaxation training once a week for six weeks. Anxiety, depression and current strain were measured in a pretest-posttest experimental design using self-report scales at baseline (1st survey), 5 weeks later (2nd survey) and during puerperium (3rd survey). Numeric Rating scales were used for measuring labour pain and satisfaction with analgesic treatment in the 3rd survey.

Fifty complete questionnaires from each group were analysed. There were no differences in mental status between the groups at baseline. Progressive muscle relaxation training significantly reduced depression levels. Trait anxiety, reflecting a person’s basic anxiety decreased significantly in both groups during puerperium. No differences in pregnancy outcomes, labour pain and analgesic requirements could be shown within both groups in general. Nonetheless, women attending more than five progressive muscle relaxation courses reported significantly less labour pain within the group and compared to controls.

Pregnant women could benefit from progressive muscle relaxation training if used continuously. Relaxation methods should be a substantial part of prenatal care and available for everyone.
Designing the User Interface of a Nitroglycerin Dose Titration Decision Support System: User-Centered Design Study
Authors: Kamboj Navpreet , Metcalfe Kelly , Chu Charlene H. , Conway Aaron
Published: July 2024

Background Nurses adjust intravenous nitroglycerin infusions to provide acute relief for angina by manually increasing or decreasing the dosage. However, titration can pose challenges, as excessively high doses can lead to hypotension, and low doses may result in inadequate pain relief. Clinical decision support systems (CDSSs) that predict changes in blood pressure for nitroglycerin dose adjustments may assist nurses with titration.

Objective This study aimed to design a user interface for a CDSS for nitroglycerin dose titration (Nitroglycerin Dose Titration Decision Support System [nitro DSS]).

Methods A user-centered design (UCD) approach, consisting of an initial qualitative study with semistructured interviews to identify design specifications for prototype development, was used. This was followed by three iterative rounds of usability testing. Nurses with experience titrating nitroglycerin infusions in coronary care units participated.

Results A total of 20 nurses participated, including 7 during the qualitative study and 15 during usability testing (2 nurses participated in both phases). Analysis of the qualitative data revealed four themes for the interface design to be (1) clear and consistent, (2) vigilant, (3) interoperable, and (4) reliable. The major elements of the final prototype included a feature for viewing the predicted and actual blood pressure over time to determine the reliability of the predictions, a drop-down option to report patient side effects, a feature to report reasons for not accepting the prediction, and a visual alert indicating any systolic blood pressure predictions below 90 mm Hg. Nurses' ratings on the questionnaires indicated excellent usability and acceptability of the final nitro DSS prototype.

Conclusion This study successfully applied a UCD approach to collaborate with nurses in developing a user interface for the nitro DSS that supports the clinical decision-making of nurses titrating nitroglycerin.
Rhetorical attacks on gender equality machineries in Spain: lessons for studying the new backlash
Authors: D. Ortbals Candice
Published: July 2024

The far-right political party in Spain, Vox, devalues women’s policy machineries through its critical rhetoric about gender and equality policies. This note puts forth two rhetorical strategies utilized by the party, ideographs and victim contests; and it argues that these strategies communicate to the public that women’s policy machineries are not necessary or appropriate. Consequently, the party’s rhetoric has noticeably challenged the previous consensus in Spain around using women’s policy machineries to improve and save women’s lives.
Exact gauge fields from anti-de Sitter space
Authors: Hirpara Savan , Kumar Kaushlendra , Lechtenfeld Olaf , Picanço Costa Gabriel
Published: July 2024

In 1977 Lüscher found a class of SO(4)-symmetric SU(2) Yang–Mills solutions in Minkowski space, which have been rederived 40 years later by employing the isometry S3 ≅ SU(2) and conformally mapping SU(2)-equivariant solutions of the Yang–Mills equations on (two copies of) de Sitter space dS4≅R×S3. Here we present the noncompact analog of this construction via AdS3 ≅ SU(1, 1). On (two copies of) anti-de Sitter space AdS4≅R×AdS3 we write down SU(1,1)-equivariant Yang–Mills solutions and conformally map them to R1,3. This yields a two-parameter family of exact SU(1,1) Yang–Mills solutions on Minkowski space, whose field strengths are essentially rational functions of Cartesian coordinates. Gluing the two AdS copies happens on a dS3 hyperboloid in Minkowski space, and our Yang–Mills configurations are singular on a two-dimensional hyperboloid dS3∩R1,2. This renders their action and the energy infinite, although the field strengths fall off fast asymptotically except along the lightcone. We also construct Abelian solutions, which share these properties but are less symmetric and of zero action.
Hall effect analysis of boron and nitrogen background concentration in undoped CVD diamond
Authors: Prikhodko D. D. , Timoshenko V. O. , Tarelkin S. A. , Kornilov N. V. , Luparev N. V. , Golovanov A. V. , Drozdova T. E. , Blank V. D.
Published: July 2024

Pure single crystal diamond is a superior material for electronic, quantum, and detection applications. The state-of-the-art level of background concentrations of boron and nitrogen in such diamonds is about 1 ppb, which is quite close to the detection limit of the best chemical analysis techniques. In this work, we show that the boron concentration of ∼0.1 ppb causes conductivity of ∼5 kΩ cm of the single crystal diamond if the nitrogen concentration is lower. In such a case, the temperature dependent Hall effect measurement provides ∼100 times better detection limit for the concentration of the impurities in diamond compared to the conventional optical techniques. As a result, we have found the background concentrations of boron and nitrogen at the level of 0.07 and 0.02 ppb, respectively. This fact leads to a conclusion that growth of the insulating diamond is possible only when the nitrogen concentration is higher than the boron concentration.
Harvesting nucleating structures in nanoparticle crystallization: The example of gold, silver, and iron
Authors: France-Lanord Arthur , Menon Sarath , Lam Julien
Published: July 2024

The thermodynamics and kinetics of nanoparticle crystallization, as opposed to bulk phases, may be influenced by surface and size effects. We investigate the importance of such factors in the crystallization process of gold, silver, and iron nanodroplets using numerical simulations in the form of molecular dynamics combined with path sampling. This modeling strategy is targeted at obtaining representative ensembles of structures located at the transition state of the crystallization process. A structural analysis of the transition state ensembles reveals that both the average size and location of the critical nucleation cluster are influenced by surface and nanoscale size effects. Furthermore, we also show that transition state structures in smaller nanodroplets exhibit a more ordered liquid phase, and differentiating between a well-ordered critical cluster and its surrounding disordered liquid phase becomes less evident. All in all, these findings demonstrate that crystallization mechanisms in nanoparticles go beyond the assumptions of classical nucleation theory.
Hofstadter-Toda spectral duality and quantum groups
Authors: Marra Pasquale , Proietti Valerio , Sheng Xiaobing
Published: July 2024

The Hofstadter model allows to describe and understand several phenomena in condensed matter such as the quantum Hall effect, Anderson localization, charge pumping, and flat-bands in quasiperiodic structures, and is a rare example of fractality in the quantum world. An apparently unrelated system, the relativistic Toda lattice, has been extensively studied in the context of complex nonlinear dynamics, and more recently for its connection to supersymmetric Yang-Mills theories and topological string theories on Calabi-Yau manifolds in high-energy physics. Here we discuss a recently discovered spectral relationship between the Hofstadter model and the relativistic Toda lattice which has been later conjectured to be related to the Langlands duality of quantum groups. Moreover, by employing similarity transformations compatible with the quantum group structure, we establish a formula parametrizing the energy spectrum of the Hofstadter model in terms of elementary symmetric polynomials and Chebyshev polynomials. The main tools used are the spectral duality of tridiagonal matrices and the representation theory of the elementary quantum group.
Room temperature-produced chalcogenide superlattices for interfacial phase-change memory
Authors: Asanuma S. , Miyata N. , Miyaguchi Y. , Horita K. , Jimbo T. , Masuda T. , Tominaga J.
Published: July 2024

Phase-change memory (PCM) using chalcogenide films composed of Ge–Sb–Te alloys is the only commercially available nonvolatile memory for storage class memory. Recently, superlattice films of GeTe and Sb2Te3, called interfacial PCM (iPCM), have attracted attention for further increasing the switching speed and reducing energy consumption. It has been reported that the iPCM device exhibits both unipolar- and bipolar-type resistive switching depending on the method of voltage application, and research is being conducted to advance its applications. However, all iPCMs reported thus far have been formed at high temperatures beyond the crystallization temperatures of GeTe and Sb2Te3 using vacuum chambers equipped with a heating stage, making mass production and practical application difficult. Here, we report on fabricated superlattice composed of S-doped GeTe and Sb2Te3 layers by combining room temperature deposition with subsequent two-step annealing. Upon evaluating the performance of this superlattice film as a bipolar-type iPCM, it was found to exhibit characteristics comparable to those of bipolar-type iPCM fabricated from high-temperature deposited superlattices. This technology is expected to contribute to an increase in the throughput of iPCM device manufacturing.
Pulse generators for enhanced magnetomotive ultrasound: Toward a cost-effective imaging for tissue characterization
Authors: Mazon Valadez Ernesto E. , Bordonal Ricardo R. , Freire José E. , Uliana João H. , Arsalani Saeideh , Collazos-Burbano David A. , Carneiro Antonio A. O. , Pavan Theo Z.
Published: July 2024

Magnetomotive ultrasound (MMUS) stands out as a promising and effective ultrasound-based method for detecting magnetic nanoparticles (MNPs) within tissues. This innovative technique relies on the precise estimation of micrometric displacements induced by the interaction of an external magnetic field with MNPs. Pulsed MMUS has emerged as a strategic alternative to address limitations associated with harmonic excitation, such as heat generation in amplifiers and coils, frequency-dependent tissue mechanical responses, and prolonged magnetic field rise times. Despite the growing interest in MMUS, the devices conventionally employed to excite the coil are not specifically tailored to generate intense magnetic fields while minimizing interference with the transient behavior of induced displacements. To bridge this gap, our work introduces the design and fabrication of two pulse generators: one based on a capacitor-discharge circuit and the other on a resonant-inverter circuit. We evaluated the performance of these pulse generators by considering parameters such as the magnetic field generated, rise and fall times, and their ability to supply sustained current for varied pulse widths across different pulse repetition frequencies. Furthermore, we carried out a practical MMUS implementation using tissue-mimicking phantoms, demonstrating the capability of both devices to achieve magnetic fields of up to 1 T and average displacements of 25 µm within the phantom. In addition, we estimated the shear wave velocity, effective shear modulus, and their temperature-dependent variations. Our findings highlight the versatility and efficacy of the proposed pulse generators and emphasize their potential as low-cost platforms for theranostic applications, enabling the assessment of targeted entities within biological tissues.
Acceleration of particle-in-cell simulations using sparse grid algorithms. II. Application to partially magnetized low temperature plasmas
Authors: Garrigues L. , Chung-To-Sang M. , Fubiani G. , Guillet C. , Deluzet F. , Narski J.
Published: July 2024

In Paper I [Garrigues et al., Phys. Plasmas 31, 073907 (2024)], we have extended the sparse PIC approach already used in the literature with the offset scheme to reduce the grid-based error. In this study, we demonstrate the ability of the offset sparse PIC algorithm to model partially magnetized low-temperature plasmas by reducing the grid-based error. In the context of multi-cusp magnetic field configurations, the offset scheme reduces the error of the current collected at the walls to less than 5% for more of the plasma conditions encountered in ion source applications. The formation of a double layer in the sheath region is also captured. In the context of the electron drift instability that occurs in the Hall thruster, the plasma properties as well as the ion velocity distribution function can be retrieved with a high enough precision without considering an initial regular grid with a smaller mesh resolution. The results also highlight the advantage of combining the electric potential at the nodes of the regular grid instead of directly combining the electric field from the component grids. Compared to the regular PIC algorithm, the typical speed-up factor is about three for a number of mesh nodes of 2562 and five for 5122.
Automatic compensation system for eccentricity error of absolute optical encoder
Authors: Zhao Changhai , Wan Qiuhua , Liang Lihui
Published: July 2024

Eccentric error is a vital part of high-precision optical encoder error. An automatic error compensation system is designed to lower the eccentric error of the encoder. On the periphery of the fan-shaped code path of the traditional encoder disk, a set of radial code paths is drawn. This radial code path is composed of several concentric circles with alternating light and dark lines. The direction of the radial code path is perpendicular to the direction of the fine code path. When the encoder rotates, the eccentricity of the encoder disk is measured by the moiré fringe signal output from the radial code channel. Based on the eccentricity error compensation algorithm, the eccentricity error of the encoder disk is compensated in real time to enhance the accuracy of the encoder. The experimental results of an encoder show that the mean square error of the encoder before the eccentricity error compensation is 21.25 arc seconds, and it is 3.66 arc seconds after compensation by this algorithm. The algorithm can significantly compensate the error caused by the eccentricity of the encoder and greatly improve the accuracy of the encoder.
Exploring drivers of behavioral willingness to use clean energy to reduce environmental emissions in rural China: An extension of the UTAUT2 model
Authors: Yin Shi , Wang Yiran , Liu Yijie , Wang Shuo
Published: July 2024

In the context of the dual-carbon target, the adoption of clean energy in rural areas is an important basis for achieving effective carbon reduction in rural areas. On the basis of the Unified Theory of Technology Acceptance and Use (UTAUT2), this study uses structural equation modeling to investigate the influencing factors of rural clean energy adoption behavior. The results are as follows: (1) Both the expected effect of rural clean energy's adoption and adoption behavior are positively correlated with intention to adopt rural clean energy, whereas the rest are negatively correlated. The willingness to adopt clean energy has the greatest impact on clean energy adoption behavior in rural areas. (2) The expected effect of clean energy's adoption, subjective norms related to clean energy's adoption, facilitation of clean energy adoption support, and habits related to clean energy adoption have partial mediating effects on the impact of clean energy adoption intention. The reliability of clean energy's adoption has a full mediating effect on the impact of clean energy adoption intention. The perceived value of clean energy adoption has no significant mediating effect on the intention to adopt clean energy. (3) Age has a significant moderating effect on perceived value, related behaviors, and intention related to adopting clean energy; education level has no significant moderating effects on facilitation support or intention to adopt clean energy; and region has no significant moderating effects on facilitation support or adoption intention.
Numerical simulations on cables attached with different shapes of lights and its mitigations by using perforated shrouds
Authors: An Miao , Wen Weihao , Li Shouying , Chen Zhengqing
Published: July 2024

To reduce the cable vibration caused by rectangular lights, the light shape is modified to be ellipsoidal and circular sections, together with the use of a perforated shroud. Numerical simulations on six types of cable-light models were conducted using computational fluid dynamics. The mean drag coefficient CD, mean and mean lift coefficient CL, mean of the ellipsoidal lights, circle lights, and perforated shroud cable are reduced compared to the rectangular light. CD, mean can be reduced by a maximum of 50%; CL, mean can be reduced by a maximum of 43%. The maximum fluctuating drag and lift coefficient are also significantly reduced. This indicates that the perforated shrouds might be useful to mitigate the vortex-induced vibration. The ellipsoidal and circular lights are significantly better than rectangular lights in terms of galloping critical wind speed. Furthermore, the perforated shroud is very beneficial for suppressing galloping vibration. The variation of Strouhal number St with the wind attack angle for the shroud rectangular light cable model is relatively smooth, all around 0.1. The wake vortices of rectangular light, ellipsoidal light, and circular light are shed alternately in a typical 2S pattern. However, the alternately shedding vortex of the shroud cable was interrupted by the flow of air through the holes. When the wind attack angle exceeds the most dangerous wind attack angle, the incoming stream cannot be reattached after separation, and the force on the cable is greatly reduced, resulting in a sudden drop in the average lift coefficient. Wind pressure in the gap between the shroud and the cable is negative. The fluctuating wind pressure coefficients on the shrouded cables are significantly lower than those of rectangular lights because of the interference effect of the outer perforated shrouds. In total, the perforated shroud is the best to reduce the galloping caused by the rectangular light.
Mechanism of temporal interface evolution and internal circulations during the droplet formation in a planar slit T-microchannel
Authors: Venkateshwarlu Akepogu , Bharti Ram Prakash
Published: July 2024

The present study has numerically explored the mechanism of interface evolution and internal flow circulations during the droplet formation in two-phase flow through a planar T-microchannel. The two-dimensional unsteady form of the conservative level set equation coupled with Navier–Stokes equations has been solved using the finite element method. The range of parameters include the contact angle (θ) from 120° to 180°, and the flow rate ratio (Qr) from 0.1 to 10 for the low capillary number (Cac≤10−2). The present study indicates that surface wettability plays a crucial role in influencing the temporal evolution of the interface. The internal flow circulation in the droplet is controlled by the axial and radial velocities primarily influenced by shear stress. The newly introduced novel “interface-to-neck ratio” parameter has provided another platform to investigate the pinch-off dynamics of droplets. Moreover, the phenomenon of droplet pinch-off is primarily initiated and driven by the Laplace pressure, defined by three distinct approaches: the pressure difference method, the determination of the minimum local radius of curvature on the rear side, and a calculation of the neck width. The predictive correlations have been established to estimate the droplet characteristics as a function of the flow rate ratio and contact angle. The findings reported have significant implications for the design of droplet dispensing systems that depend on surface wettability as a critical regulating parameter.
Investigation on gas–liquid–solid three-phase flow model and flow characteristics in mining riser for deep-sea gas hydrate exploitation
Authors: Guo Xiaoqiang , Chen Xinghan , Xu Jie , Li Xinye , Nie Yuxin , Dai Liming
Published: July 2024

In response to the problem of gas–liquid–solid three-phase flow in deep-sea hydrate extraction pipelines, a gas–liquid–solid three-phase flow model considering the dynamic decomposition of hydrates is established using continuity equations, momentum equations, and energy equations. The numerical solution of the theoretical model is achieved using the finite difference method. Comparing the theoretical model with the experimental results, the results showed that the average error of gas holdup, liquid holdup, solid phase content, gas phase velocity, liquid phase velocity, and solid phase velocity obtained from the theory and experiment are 8.24%, 0.41%, 1.88%, 5.80%, 2.81%, and 2.22%, respectively, which verified the correctness of the theoretical model. On this basis, the influences of hydrate abundance, liquid phase displacement, and wellhead backpressure on the gas–liquid–solid three-phase flow characteristics in the pipeline were investigated, and it was found that the gas holdup rate will increase with the increase in hydrate abundance, liquid phase displacement, and wellhead backpressure, with the influence of hydrate abundance being more sensitive. The liquid holdup rate increases with the increase in hydrate abundance and liquid phase displacement, but decreases first and then increases toward the wellhead position with the increase in wellhead backpressure. The solid phase content decreases with the increase in hydrate abundance, and first increases and then decreases toward the wellhead position as the liquid phase displacement and wellhead backpressure increase. The influence of gas phase velocity on the abundance of hydrates is relatively small, but it increases with the increase in liquid phase displacement. When the wellhead backpressure increases, the instantaneous increase then tends to flatten out. The influence of hydrate abundance on the liquid phase velocity is also relatively small, but it increases with the increase in liquid phase displacement and decreases with the increase in wellhead backpressure. The solid phase velocity will increase with the increase in hydrate abundance and liquid phase displacement, but it will not show significant changes with the change of wellhead backpressure. The research results can provide a theoretical basis for the safety of hydrate mining.
Ultrafast (≈10 GHz) mid-IR modulator based on ultrafast electrical switching of the light–matter coupling
Authors: Malerba Mario , Pirotta Stefano , Aubin Guy , Lucia L. , Jeannin M. , Manceau J.-M. , Bousseksou A. , Lin Q. , Lampin J.-F. , Peytavit E. , Barbieri S. , Li L. H. , Davies A. G. , Linfield E. H. , Colombelli Raffaele
Published: July 2024

We demonstrate a free-space amplitude modulator for mid-infrared radiation (λ ≈ 9.6 μm) that operates at room temperature up to at least 20 GHz (above the −3 dB cutoff frequency measured at 8.2 GHz). The device relies on the ultrafast transition between weak- and strong-coupling regimes induced by the variation of the applied bias voltage. Such transition induces a modulation of the device reflectivity. It is made of a semiconductor heterostructure enclosed in a judiciously designed array of metal–metal optical resonators, that—all-together—behave as an electrically tunable surface. At negative bias, it operates in the weak light–matter coupling regime. Upon application of an appropriate positive bias, the quantum wells populate with electrons, and the device transitions to the strong-coupling regime. The modulator transmission remains linear with input radio frequency power in the 0–9 dBm range. The increase in optical powers up to 25 mW exhibit a weak beginning of saturation a little bit below.
Numerical simulation of submarine landslide tsunamis based on the smoothed particle hydrodynamics model
Authors: Li Wei-qin , Chen Yong-kun , Liu Yong , Meringolo Domenico D.
Published: July 2024

This paper establishes a SPH (Smoothed Particle Hydrodynamics) model for simulating underwater landslides based on the mixture theory. This model requires only one layer of particles, which greatly improves the computational efficiency compared with the traditional two-layer particle simulation for a mixture theory scheme. In the numerical model, based on a mixture theory, submerged landslide flow is regarded as a mixture of water and sediment phases and is discretized into a series of SPH mixed particles employing the volume fraction of the sediment phase. Using this volume fraction, a convection–diffusion term is calculated to represent the material transport between the water phase and the sediment phase. In addition, based on this volume fraction, the SPH mixed particles at any location in the considered domain are classified into three categories: (i) pure water, (ii) low-concentration suspended sediment, and (iii) high-concentration sediment. Pure water is treated as a Newtonian fluid. High-concentration sediment is modeled as a non-Newtonian fluid, and the Herschel–Bulkley–Papanastasiou rheological model is used to describe the viscous forces. The viscosity of the low-concentration suspended sediment, which acts as a transition layer between pure water and high-concentration sediment, is derived from the Chezy relation. A comparison of the numerical and experimental results demonstrates the high accuracy of the present numerical scheme. Using this validated numerical model, underwater landslides are simulated. Specifically, the effects of landslide deformation and compaction degree on the amplitudes of the surge wave crest and trough are investigated.
Design, optimization, and performance analysis of a subsonic high-through flow turbine
Authors: Dong Zeda , Zhang Weitao , Zeng Jun , Sun Yue , Cai Le , Wang Songtao , Wen Fengbo
Published: July 2024

This paper presents the design method and numerical analysis results of a two-stage high-through flow (HTF) high-pressure turbine. Compared to conventional design principles, the HTF turbine proposed in this study is a kind of high flow coefficient turbine. This design scheme enables the turbine to effectively increase the output power and thrust while maintaining the same windward area. At the design speed, the pressure ratio of the HTF turbine is 3.8, with an adiabatic efficiency of 91.46%. The flow coefficients of the first and second stage are 0.76 and 0.86, respectively, and the loading coefficients are 2.55 and 1.47. Detailed design parameters, flow characteristics, and aerodynamic performance are presented in this paper. Based on the preliminary design result, the second stage turbine was optimized for a wide range of operating conditions. The computational fluid dynamics simulation results show that compared with the traditional turbine, the loading form of the HTF turbine changes from aft-loaded to front-loaded. In addition, there is a certain increase in tip leakage of the turbine. This study achieves high efficiency, while increasing the turbine flow rate, and provides a corresponding reference for the design method of improving turbine flow capacity.
Numerical study and experimental validation: A portioned calculation method for a large atomization field
Authors: Chen Qingshan , Zhang Qinrui , Wang Qianglong , Guo Kailun , Wang Mingjun , Tian Wenxi , Qiu Suizheng , Su Guanghui
Published: July 2024

Atomization and sprays are widely used in industry and agriculture. An appropriate atomization simulation method is essential in analyzing the liquid film-breaking process and atomization performance, especially in large-scale atomization field calculations. This study innovatively proposes a portioned method that combines existing fundamental atomization calculation models to balance computational accuracy and speed, finally achieving a full-scale numerical study of large atomization fields. This study employs the volume of fluid (VOF) model to measure the two-phase flow in the inner flow field and applies the discrete particle model (DPM) to analyze droplet behavior in the far-atomization field. In the near-atomization field, the VOF-to-DPM method connects the nozzle with the jet space, providing an effective numerical simulation of the liquid film formation and droplet breakup processes. Additionally, experiments on atomization using a pressure-swirl nozzle at different flow rates were conducted. Experimental data, such as atomization cone angle, flow distribution, and droplet particle size distribution, were obtained, and numerical calculations were performed using the large atomization field partitioned calculation model. The simulation results are utilized to explain the mechanisms of liquid film disintegration, while the experimental results are employed to validate the accuracy of the numerical model. The comparison revealed that the calculated results of the partitioned simulation approach align well with the experimental data. The maximum error in flow characteristics is 9.53%, in atomization cone angle is 6.16%, and in flow distribution is 3.67%, and there is a good agreement in particle size distribution with a maximum error of 17.58% in Sauter mean diameter, validating the accuracy of the portioned calculation method for large atomization fields.
An amplitude-dependent nonlinear approach for vortex-induced vibration evaluation of long-span bridges with inhomogeneous cross-sections
Authors: Pan Junzhi , Ti Zilong , Yang Ling , Li Yongle , Zhu Jin
Published: July 2024

In the design of modern long-span bridges, inhomogeneous cross sections are increasingly used to meet various requirements, posing challenges in the investigation of vortex-induced vibration (VIV). This paper introduces a nonlinear approach with a focus on amplitude dependency in VIV for inhomogeneous bridges. It presents an inhomogeneous vortex-induced force model with amplitude-dependent parameters to capture spanwise variations in aerodynamics. These parameters are identified through multiple sectional wind tunnel tests. VIV amplitudes are determined by searching for solutions under the zero-damping condition for VIV. An illustrative bridge with an inhomogeneous fairing design is employed as an engineering application. The approach is rigorously validated with experimental data and applied to assess the prototype VIV behavior of the bridge with different fairing lengths. An optimal fairing length, constituting 40% of the main girder length in the mid-span, is identified to strike a balance between VIV performance and material usage. Discussion for the prediction results provides insights into the effects of fairing length inhomogeneity on VIV. In practice, deploying fairings in the large mode shape sections of the main girder achieves VIV mitigation comparable to a full-span installation.
Information-theoretical limit on the estimates of dissipation by molecular machines using single-molecule fluorescence resonance energy transfer experiments
Authors: Song Kevin , Makarov Dmitrii E. , Vouga Etienne
Published: July 2024

Single-molecule fluorescence resonance energy transfer (FRET) experiments are commonly used to study the dynamics of molecular machines. While in vivo molecular processes often break time-reversal symmetry, the temporal directionality of cyclically operating molecular machines is often not evident from single-molecule FRET trajectories, especially in the most common two-color FRET studies. Solving a more quantitative problem of estimating the energy dissipation/entropy production by a molecular machine from single-molecule data is even more challenging. Here, we present a critical assessment of several practical methods of doing so, including Markov-model-based methods and a model-free approach based on an information-theoretical measure of entropy production that quantifies how (statistically) dissimilar observed photon sequences are from their time reverses. The Markov model approach is computationally feasible and may outperform model free approaches, but its performance strongly depends on how well the assumed model approximates the true microscopic dynamics. Markov models are also not guaranteed to give a lower bound on dissipation. Meanwhile, model-free, information-theoretical methods systematically underestimate entropy production at low photoemission rates, and long memory effects in the photon sequences make these methods demanding computationally. There is no clear winner among the approaches studied here, and all methods deserve to belong to a comprehensive data analysis toolkit.
Extracellular vesicle and lipoprotein diagnostics (ExoLP-Dx) with membrane sensor: A robust microfluidic platform to overcome heterogeneity
Authors: Kumar Sonu , Senapati Satyajyoti , Chang Hsueh-Chia
Published: July 2024

The physiological origins and functions of extracellular vesicles (EVs) and lipoproteins (LPs) propel advancements in precision medicine by offering non-invasive diagnostic and therapeutic prospects for cancers, cardiovascular, and neurodegenerative diseases. However, EV/LP diagnostics (ExoLP-Dx) face considerable challenges. Their intrinsic heterogeneity, spanning biogenesis pathways, surface protein composition, and concentration metrics complicate traditional diagnostic approaches. Commonly used methods such as nanoparticle tracking analysis, enzyme-linked immunosorbent assay, and nuclear magnetic resonance do not provide any information about their proteomic subfractions, including active proteins/enzymes involved in essential pathways/functions. Size constraints limit the efficacy of flow cytometry for small EVs and LPs, while ultracentrifugation isolation is hampered by co-elution with non-target entities. In this perspective, we propose a charge-based electrokinetic membrane sensor, with silica nanoparticle reporters providing salient features, that can overcome the interference, long incubation time, sensitivity, and normalization issues of ExoLP-Dx from raw plasma without needing sample pretreatment/isolation. A universal EV/LP standard curve is obtained despite their heterogeneities.
Bifurcations and mixed mode oscillations in a bi-stable plasma model with slow parametric excitation
Authors: Chen Zhenyang
Published: July 2024

In this study, considering a bi-stable plasma model with slow parametric excitation, the bifurcation of periodic and chaotic responses as well as the resulting fast–slow motions is discussed analytically and numerically. For a nonautonomous fast sub-system, the generalized harmonic balancing method is utilized to obtain an averaged system. Bifurcation analysis about the averaged system shows that the critical manifolds form a S-shape structure. Meanwhile, supercritical and subcritical period doubling (PD) occurs on the upper branch simultaneously. As the frequency of the external excitation changes, bifurcation points on the limit cycle manifolds can present different relative locations. Moreover, an additional bi-stable structure induced by Cusp bifurcation emanates from the upper branch. On the other hand, the existence of a chaotic attractor and the corresponding boundary crisis phenomenon are verified using the Melnikov method and the basin of attraction. The structures of the numerical bifurcation diagram show good agreements with the analytical results. Considering two cases of low-frequency excitation, the corresponding fast–slow dynamics are discussed. It is found that, when the fast–slow flow passing the subcritical PD point, a low frequency with different magnitudes will lead to two patterns of bifurcation delay, i.e., the typical one and the excessive delay, which suppress the PD. As for the boundary crisis point, the slow passage effects show no distinct influence. Thus, three transition mechanisms based on two cases of the bifurcation structure are explained, including “fold of cycle–fold of cycle” type, “fold of cycle–delayed subcritical PD” type, and “fold of cycle–boundary crisis” type.
High intensity proton source based on a hollow-cathode reflex discharge
Authors: Gushenets V. I. , Bugaev A. S. , Oks E. M.
Published: July 2024

We describe here the electrode system, design, and parameters of an ion source based on a Penning-type hollow-cathode reflex discharge developed for generation of proton beams. Especially for proton beam generation, a modified geometry of both hollow and reflex cathodes was fabricated. The working gas is molecular hydrogen. Ion extraction and beam formation are performed using a three-electrode single-aperture optical system with a 3-mm diameter emission aperture. At an accelerating voltage of 33–35 kV and a discharge current of 0.55 A in continuous mode, the ion beam current was 15–17 mA, and in pulsed mode, at a discharge current of about 2 A, the beam current was 55 mA. The beam consists mainly of H+, H2+, and H3+ ions, with the proton (H+) fraction up to 27% in continuous mode and 40% in pulsed mode.
Disruption of the ZFP574–THAP12 complex suppresses B cell malignancies in mice
Authors: Zhong Xue , Moresco James J. , SoRelle Jeffrey A. , Song Ran , Jiang Yiao , Nguyen Mylinh T. , Wang Jianhui , Bu Chun Hui , Moresco Eva Marie Y. , Beutler Bruce , Choi Jin Huk
Published: July 2024

Despite the availability of life-extending treatments for B cell leukemias and lymphomas, many of these cancers remain incurable. Thus, the development of new molecular targets and therapeutics is needed to expand treatment options. To identify new molecular targets, we used a forward genetic screen in mice to identify genes required for development or survival of lymphocytes. Here, we describeZfp574, an essential gene encoding a zinc finger protein necessary for normal and malignant lymphocyte survival. We show that ZFP574 interacts with zinc finger protein THAP12 and promotes the G1-to-S-phase transition during cell cycle progression. Mutation of ZFP574 impairs nuclear localization of the ZFP574–THAP12 complex. ZFP574 or THAP12 deficiency results in cell cycle arrest and impaired lymphoproliferation. Germline mutation, acute gene deletion, or targeted degradation of ZFP574 suppressed Myc-driven B cell leukemia in mice, but normal B cells were largely spared, permitting long-term survival, whereas complete lethality was observed in control animals. Our findings support the identification of drugs targeting ZFP574–THAP12 as a unique strategy to treat B cell malignancies.
Monitoring the evolution of optical coatings during thermal annealing with real-time, in situ spectroscopic ellipsometry
Authors: Colace Stefano , Samandari Shima , Granata Massimo , Amato Alex , Caminale Michael , Michel Christophe , Gemme Gianluca , Pinard Laurent , Canepa Maurizio , Magnozzi Michele
Published: July 2024

Thermal annealing plays a key role in optimizing the properties of amorphous optical coatings. In the field of gravitational wave detection (GWD), however, the effects of annealing protocols on the interferometry mirror coatings have been explored primarily by ex post analysis. As a result, the dynamics of the coatings properties during annealing is still poorly known, potentially leading to suboptimal performance. Here, using real-time, in situ spectroscopic ellipsometry (SE) we have tracked the refractive index and thickness of a titania-tantala coating during controlled annealing. We have tested the material and the annealing protocol used in current GWD mirrors. The annealing cycle consisted of a heating ramp from room temperature to 500 ∘C, followed by a 10-h plateau at the same temperature and the final cooling ramp. SE measurements have been run continuously during the entire cycle. Significant variations in the thickness and refractive index, which accompany the coating structural relaxation, have been recorded during the heating ramp. These variations start around 200 ∘C, slightly above the deposition temperature, and show an increased rate in the range 250 ∘C–350 ∘C. A smaller, continuous evolution has been observed during the 10-h high-temperature plateau. The results offer suggestions to modify the current annealing protocol for titania-tantala coatings, for example by increasing the time duration of the high-temperature plateau. They also suggest an increase in the substrate temperature at deposition. The approach presented here paves the way for systematic, real-time investigations to clarify how the annealing parameters shape the properties of optical coatings, and can be leveraged to define and optimize the annealing protocol of new candidate materials for GWD mirrors.
Compact quad-channel filtering diplexer using meander hairpin ring resonator aided by grey wolf algorithm
Authors: Liu Haiwen , Wang Sidong , Sun Mingli , Song Zeren , Tian Hongliang
Published: July 2024

In this paper, a compact quad-channel filtering diplexer using meander hairpin ring resonators (M-HRR) aided by grey wolf algorithm (GWA) is proposed. To realize a compact size of the multi-channel diplexer, the form of a meander-line structure is applied to the hairpin ring resonator for the miniaturization of the proposed quad-channel diplexer. Then, using the coupling topology of the 0° feeding structure, a transmission zero is generated between two resonant frequencies of M-HRR to improve the band-edge selectivity and band-to-band isolation of the diplexer. To address the problematic challenge of the complexity in designing the multi-channel diplexer with a time-consuming optimization manually, an intelligent GWA is utilized to optimize the physical layout of the designed circuit to achieve the desired performance of the diplexer rapidly. Furthermore, different kinds of intelligent algorithms are implemented and compared under identical conditions. Finally, a quad-channel filtering diplexer centering at 3.28/3.75/4.32/4.75 GHz with 3 dB fractional bandwidth of 5.4%, 2.9%, 4.9%, and 3.2% respectively is fabricated and measured. The circuit occupies a compact size of 0.22λ
g × 0.20λ
g. Good accordance is observed between the simulated and measured frequency responses.
Green-solvent-processed lead-free perovskite solar cells
Authors: He Linfeng , Zhang Xin , Chen Xinyao , Cheng Jin , Li Zhenjun , Li Junming
Published: July 2024

Tin-based perovskite has been considered as one of the most potential candidates for lead-based perovskite. The solution proceed method was widely utilized in fabricating tin perovskite solar cells. So far, all fabrication processes for tin perovskite solar cells involved toxic organic solvents, which is contrary to the development of environmentally friendly perovskite solar cells. In this study, we report for the first time, by using a mixed green solvent N-diethyl formamide and green 1,3-dimethyl-3,4,5,6-Tetrahydro-2 (1H)-pyrimidinone as precursor solvent, and a green solvent dibutyl ether as antisolvent, a high-quality FA0.75MA0.25SnI3 film was achieved. The optical band gap of the prepared perovskite layer was 1.36 eV, which was close to the ideal band gap. The green-solution-proceed perovskite films showed reduced defect density. As a consequence, the champion green-solution-proceed photovoltaic device achieved a power conversion efficiency of 4.4%. Moreover, it still maintains 80% of the initial efficiency after 600 h of storage in a nitrogen atmosphere. This work would promote the perovskite solar cells from a ‘new’ technique to a ‘new and green’ technique.
Multi-step intelligent prediction of shield machine position attitude on the basis of BWO-CNN-LSTM-GRU
Authors: Liu Xuanyu , Zhang Wenshuai , Mengting Jiang , Wang Yudong , Ma Lili
Published: July 2024

Realizing automatic control of shield machine tunneling attitude is a challenging problem. Realizing multi-step intelligent prediction for attitude and position is an important prerequisite for solving this problem in the tunneling process with complex and varied geological environments. In this paper, a multi-step intelligent predictive scheme based on beluga whale optimization-convolutional neural network-Long Short-term memory-gated recurrent unit (BWO-CNN-LSTM-GRU) is proposed for shield machine position attitude. First, Pearson correlation analysis is utilized to determine the input feature variables from the construction data and temporalize the input features. Subsequently, CNN-LSTM-GRU predictive models are established for the six positional parameters, separately. Among them, CNN performs feature extraction on the input variables, and LSTM-GRU realizes the predictions for the target positional parameters. In the end, the optimization of the convolutional layer dimension, the number of convolutional layers, iterations, the learning rate, the number of neurons in the LSTM layer and GRU layer of each position predictive model is performed on the basis of BWO, separately, and the best hyperparameters found are built into a BWO-CNN-LSTM-GRU position predictive model, which realizes the multi-step intelligent predictions for the shield machine’s position. The proposed approach is examined by utilizing the Beijing Metro Line 10. The results show that the predictive deviation of the position predictive model is within 3 mm, and the positional trajectory points obtained on the basis of the predicted values and the 3D coordinate system are highly coincident with the actual trajectory points. Therefore, the approach provides a more accurate predictive result for shield attitude and position and can provide a decision-making scheme for further realizing the coordinated autonomous control of shield machine.