bluuebunny/crossref_metadata_2025_split huggingface dataset:
JOYS+ study of solid-state 12C/13C isotope ratios in protostellar envelopes
Authors: Brunken N. G. C. , van Dishoeck E. F. , Slavicinska K. , le Gouellec V. J. M. , Rocha W. R. M. , Francis L. , Tychoniec L. , van Gelder M. L. , Navarro M. G. , Boogert A. C. A. , Kavanagh P. J. , Nazari P. , Greene T. , Ressler M. E. , Majumdar L. 
Published: November 2024

Context. The carbon isotope ratio is a powerful tool for studying the evolution of stellar systems due to its sensitivity to the local chemical environment. Recent detections of CO isotopologs in disks and exoplanet atmospheres revealed a high variability in the isotope abundance, ponting towards significant fractionation in these systems. In order to fully understand the evolution of this quantity in stellar and planetary systems, however, it is crucial to trace the isotope abundance from stellar nurseries to the time of planet formation. During the protostellar stage, the multiple vibrational modes of CO2 and CO ice, which peak in the near- and mid-infrared, provide a unique opportunity to examine the carbon isotope ratio in the solid state. With the current sensitivity and wide spectral coverage of the James Webb Space Telescope, the multiple weak and strong absorption features of CO2 and CO have become accessible at a high signal-to-noise ratio in solar-mass systems.
Aims. We aim to study the carbon isotope ratio during the protostellar stage by deriving column densities and ratios from the various absorption bands of CO2 and CO ice, and by comparing our results with the ratios derived in other astronomical environments.
Methods. We quantify the 12CO2/13CO2 and the 12CO/13CO isotope ratios in 17 class 0/I low-mass protostars from the 12CO2 ν1 + ν2 and 2ν1 + ν2 combination modes (2.70 µm and 2.77 µm), the 12CO2 ν3 stretching mode (4.27 µm), the 13CO2 ν3 stretching mode (4.39 µm), the 12CO2 ν2 bending mode (15.2 µm), the 12CO 1-0 stretching mode (4.67 µm), and the 13CO 1-0 stretching mode (4.78 µm) using the James Webb Space Telescope NIRSpec and MIRI observations. We also report a detection of the 2-0 overtone mode of 12CO at 2.35 µm.
Results. The column densities and 12CO2/13CO2 ratios derived from the various CO2 vibrational modes agree within the reported uncertainties, and we find mean ratios of 85 ± 23, 76 ± 12, and 97 ± 17 for the 2.70 µm band, the 4.27 µm band, and the 15.2 µm band, respectively. The main source of uncertainty on the derived values stems from the error on the band strengths; the observational errors are negligible in comparison. Variation of the 12CO2/13CO2 ratio is observed from one source to the next, which indicates that the chemical conditions of their envelopes might be genuinely different. The 12CO/13CO ratios derived from the 4.67 µm band are consistent, albeit elevated with respect to the 12CO2/13CO2 ratios, and we find a mean ratio of 165 ± 52.
Conclusions. These findings indicate that ices leave the prestellar stage with elevated carbon isotope ratios relative to the overall values found in the interstellar medium, and that fractionation becomes a significant factor during the later stages of star and planet formation.
Expert Opinion for Defining a Severe Bleeding Phenotype to Guide Prophylaxis in Patients with Nonsevere Hemophilia
Authors: Pfrepper Christian , Ettingshausen Carmen Escuriola , Klamroth Robert , Oldenburg Johannes , Olivieri Martin 
Published: November 2024

AbstractProphylaxis is the standard of care for patients with severe hemophilia, patients with moderate hemophilia, or those with another congenital bleeding disorder that is associated with a severe bleeding phenotype and/or a high risk of spontaneous life-threatening bleeding. Patients with nonsevere hemophilia (factor VIII [FVIII] ≥ 1%) may also have a bleeding phenotype that requires prophylaxis. To date, however, there are no clear criteria as to when prophylaxis is indicated in these patients. Also, the term “severe bleeding phenotype (SBPT)” is neither included in the definitions of the International Society on Thrombosis and Haemostasis (ISTH) nor specified in the World Federation of Hemophilia (WFH) guidelines. Based on our personal experience and available evidence, we propose the criteria we use to define an SBPT and when we consider offering prophylaxis in patients with nonsevere hemophilia. Our proposals can be the basis for discussions in the community about the assessment of SBPT and the initiation of prophylaxis in patients with nonsevere hemophilia without inhibitors.
Auswirkungen der COVID-19-Pandemie auf die Zuweisungen in die nephrologische Hochschulambulanz des Universitätsklinikums Jena
Authors: Ruhe Johannes , Koch Annegret , Koch Annegret , Wolf Gunter 
Published: November 2024

ZUSAMMENFASSUNGIn einer retrospektiven Datenerhebung gingen wir der Fragestellung nach, inwieweit sich die Patientenzahlen und Arzt-Patienten-Kontakte der nephrologischen Hochschulambulanz am Universitätsklinikum Jena während und nach der COVID-19-Pandemie verändert haben. Während stationäre Fallzahlen rückläufig waren, zeigte sich, dass in den beiden präpandemischen Jahren 2018 und 2019 die Fallzahlen auf vergleichbarem Niveau waren, während der Pandemie (insbesondere von 2020 auf 2021) anstiegen und dieser ansteigende Trend bis 2023 anhielt. Dies bringt Herausforderungen in der Patientenbetreuung – insbesondere in der Logistik und im Ressourcen- sowie Personalmanagement – mit sich. Parallel dazu verzeichnen wir eine Verdoppelung der hausärztlichen Zuweisungen von 2018–2021. Der führende Grund der Zuweisung bestand 2018/2019 in ergänzender Hypertoniediagnostik und -therapie sowie der Mitbetreuung eines Kreatininanstiegs bei bekannter sekundärer (hypertensiver, diabetischer oder vaskulärer) Nephropathie. Hingegen wurden während der Pandemie Patienten vermehrt zur Abklärung und Mitbetreuung einer neuen Proteinurie oder (Mikro-)Hämaturie sowie zur Mitbehandlung vermuteter primärer Glomerulonephritisformen überwiesen. Als Hauptursache ist möglicherweise das verbesserte Screening auf Proteinurie per Spontanurindiagnostik im hausärztlichen Setting und in diesem Zuge auch die erhöhte Detektion einer Erythrozyturie zu sehen. Zudem steigt die Rate an Patienten mit Diabetes mellitus und arterieller Hypertonie trotz moderner Therapiemethoden stetig an. Mittel- bis langfristig müssen bisherige Strukturen adaptiert werden, um den steigenden Patientenzahlen mit bisheriger Qualität gerecht zu werden.
Electronic structure of 2(5H)-thiophenone studied by UPS and soft x-ray spectroscopy
Authors: Plekan Oksana , Ponzi Aurora , Grazioli Cesare , Coreno Marcello , de Simone Monica , Morini Filippo , Bernes Elisa , Fronzoni Giovanna , Toffoli Daniele 
Published: November 2024

Abstract
The electronic structure of 2(5H)-thiophenone in the gas phase was investigated by ultraviolet photoelectron spectroscopy and x-ray photoemission spectroscopy (XPS) and near edge x-ray absorption fine structure (NEXAFS) spectroscopy at the C 1s, O 1s, and S 2p edges. All assignments of the experimental results are supported by both ab-initio electron propagator outer-valence Green’s function (OVGF) calculations for the valence photoemission bands and density functional theory (DFT) and relativistic time dependent DFT calculations for the core levels XPS and NEXAFS spectra. Overall good agreement between experiment and theory is observed; this is especially true for core electron excitations which has permitted an unambiguous assignment of the observed spectral features in terms of single-particle excitations to virtual molecular orbitals. The assignment of the valence band spectra based on OVGF calculations, although satisfactory, points to the importance of electron correlations effects that partially break the single particle picture of ionization.
Microstructural and mechanical properties study of various lattice structures of SS316L-CNTs nano composites fabricated through additive manufacturing
Authors: Yadav B N , Alfantazi Akram , Alazemi Abdullah A , Mandal Ajay , Lin Pai-Chen , Huang Pei-Chen , Yeh De-Yi , Liu De-Shin 
Published: November 2024

Abstract
In this work, various lattice structures, such as face-centered (FCC), body-centered (BCC), gyroid (GD), and bare gyroid (BGD (without CNTs)) with four different porosities (60%, 70%, 80%, and 90%), were prepared through the selective laser melting additive manufacturing process. Stainless steel 316 l alloy was utilized as the base material, while 0.2 wt.% functionalized carbon nanotubes (CNTs) were employed as reinforcement. The uniform dispersion of CNTs was analyzed using FESEM, TEM, and Raman spectroscopy. The results indicated that the plateau stress increases with the addition of CNTs, irrespective to the lattice structure. Also, in case of relative density the plateau stress increases with increasing the relative density. Similarly, the energy absorption also increases with the addition of CNTs regardless to the lattice structure. However, with increasing relative densities, energy absorption increases up to the 30% deformation regardless to the lattice structure and followed order was the BCC > FCC > GD > BGD.
Numerical simulation of cathode-spot crater and droplet formation with linear and circular motion process
Authors: Wang Lijun , Wang Cong , Gao Hexiao , Zhang Runming , Xie Yiduo 
Published: November 2024

Abstract
In this paper, a three-dimensional cathode spot erosion model is proposed to study the development of cathode spot motion process on the surface of copper cathode. The formation and development process of cathode spots motion without external magnetic field is studied. In this model, energy flux density, pressure, and current value are considered as external parameters. The simulation results compared the cathode spot ablation trajectories and temperature distribution under different motion forms and motion velocities. The results indicated that during the spots expansion process, the flow of liquid metal will form a convex structure on the surface of the cathode and a hollow structure inside the cathode. Comparing different motion types, the annular motion significantly increased the roughness of the cathode surface. With the increase of the speed of spots movement, the interaction between the craters is significantly weakened, which will reduce the temperature and the roughness of the cathode surface. The simulation results are consistent with the experimental results.
Negative piezoelectricity in quasi-two/one-dimensional ferroelectrics
Authors: Ding Ning , Dong Shuai 
Published: November 2024

Abstract
In recent years, the investigation of low-dimensional ferroelectrics has attracted great attention for their promising applications in nano devices. Piezoelectricity is one of the most core properties of ferroelectric materials, which plays an essential role in micro-electromechanical systems. Very recently, anomalous negative piezoelectricity has been predicted/discovered in many quasi-two-dimensional layered ferroelectric materials. In this Topical Review, we will briefly introduce the negative piezoelectricity in quasi-two/one-dimensional ferroelectrics, including its fundamental concepts, typical materials, theoretical predictions, as well as experimental phenomena. The underlying physical mechanisms for negative piezoelectricity are divergent and vary case by case, which can be categorized into four types: first, the soft van der Waals (vdW) layer is responsible for the volume shrinking upon pressure while the electric dipoles are from the non vdW layer; second, the noncollinearity of local dipoles creates a ferrielectricity, which leads to orthogonal ferroelectric and antiferroelectric axes; third, the electric dipoles come from interlayer/interchain couplings, which can be enhanced during the volume shrinking; fourth, the special buckling structure contributes to local dipoles, which can be enhanced upon pressure. In real materials, more than one mechanism may work together. Finally, future directions of negative piezoelectricity and their potential applications are outlined.
Enhanced energy storage performance in BaZrxTi1–xO3 lead-free ferroelectrics near phase transitions
Authors: Vu Ba-Hieu , Dang Ha Thi , Dinh Van-Hai , Lich Le Van 
Published: November 2024

Abstract
The present study explores the energy storage properties of BaZr
x
Ti

1
−
x

O3 through phase-field modeling, focusing on the impact of composition and temperature on energy storage performance. The obtained results reveal a variety of polarization phases and configurations based on Zr compositions and temperatures. A detailed phase diagram for temperature-composition of BaZr
x
Ti

1
−
x

O3 is established, closely aligning with experimental measurements. Variations in Zr content and temperature have a significant impact on the polarization-electric field (P − E) response, influencing the energy storage properties. Calculations of energy storage properties are derived from the P − E response. In addition, a thorough diagram is developed to illustrate the discharge energy density of BaZr
x
Ti

1
−
x

O3 as a function of temperature and composition. Notably, high discharge energy density is achievable near the Curie temperature, corresponding to the transition from ferroelectric to paraelectric phase. Furthermore, the present study emphasizes the importance of the disparity between maximum and remanent polarization, as well as the electric field-dependent effective permittivity, in determining the discharge energy density.
Challenges faced by women and persons excluded because of their ethnicity and race in physics learning environments: review of the literature and recommendations for departments and instructors
Authors: Maries Alexandru , Li Yangquiting , Singh Chandralekha 
Published: November 2024

Abstract
Physics, as a discipline, has long struggled with pervasive stereotypes and biases about who is capable and can excel in it. Physics also ranks among the least diverse among all science, technology, engineering, and mathematics (STEM) disciplines, often cultivating and fostering learning environments that lack inclusivity and equity. Moreover, stereotypes about brilliance, inequitable physics learning environments and the overall physics culture not only impact the experiences and outcomes of students who major in physics, but also those from other STEM disciplines who must take physics courses. Here we undertake a narrative review, delving into research concerning diversity, equity, and inclusion within undergraduate physics education. We concentrate on the experiences of women and persons excluded due to their ethnicity or race in physics, aiming to shed light on the alarming current situation. The review begins with a few concrete examples of exclusionary experiences that research shows are common for women in physics and can reduce their interest or motivation to pursue a physics major. Then, we provide our conceptualization of equity in physics learning environments and describe the frameworks informing the perspective taken in the review. We then discuss issues related to inequities in physics learning environments, including but not limited to inequities in academic performance, participation, and persistence in physics, as well as psychological factors such as physics self-efficacy, perceived recognition, social belonging, mindset beliefs, and others. We also review research on factors commonly associated with the lack of diversity, equity, and inclusion in physics including the lack of role models, stereotypes associating physics with brilliance, and the overall prototypical culture of physics. We emphasize that addressing these systemic issues in physics requires a holistic approach. We conclude with a list of recommendations for physics departments and instructors on how they can play an important role in transforming the physics culture and making the learning environments equitable and inclusive so that all students can engage in learning physics and enjoy it while feeling supported.
Asynchronous quantum repeater using multiple quantum memory
Authors: Li Chen-Long , Yin Hua-Lei , Chen Zeng-Bing 
Published: November 2024

Abstract
A full-fledged quantum network relies on the formation of entangled links between remote location with the help of quantum repeaters. The famous Duan–Lukin–Cirac–Zoller quantum repeater protocol is based on long distance single-photon interference (SPI), which not only requires high phase stability but also cannot generate maximally entangled state. Here, we propose a quantum repeater protocol using the idea of post-matching, which retains the same efficiency as the SPI protocol, reduces the phase-stability requirement and can generate maximally entangled state in principle. We also outline an implementation of our scheme based on the Kerr nonlinear resonator. Numerical simulations show that our protocol has its superiority by comparing with existing protocols under a generic noise model and show the feasibility of building a large-scale quantum communication network with our scheme. We believe our work represents a crucial step towards the construction of a fully-connected quantum network.
Design and experimental evaluation of a compact inchworm piezoelectric actuator with bridge-type displacement amplification mechanism
Authors: Li Hailong , Li Yuntao , Deng Shaolong , Shan Junhui , Bai Deen 
Published: November 2024

Abstract
Miniaturization is an important direction in piezoelectric actuator research, with related efforts focusing on reducing structural complexity and simplifying guiding mechanisms. However, some actuators experience backward movement after miniaturization design. There remains significant room for improvement in mechanism configuration and the design of flexible amplification mechanisms to further reduce actuator size. In this paper, a compact inchworm actuator with bridge-type displacement amplification mechanism (BTDAM) is proposed, which does not require an additional guiding mechanism and adopts a three-dimensional packaging approach with high space utilization and a compact amplification mechanism. Because the output capacity of the BTDAM significantly impacts the operating performance of the actuator, mathematical modeling and simulation analysis are conducted. Compared with the experimental results of the amplification ratio of the BTDAM, the error of the theoretical model was 5.05%, and that of the finite element method analysis was 9.1%. The dimensions of the prototype are 23 × 23 × 19 mm, and it weighs 23 g. The test results indicate that the proposed actuator can achieve stable stepping motion without backward movement. Under a voltage of 75 V, the proposed actuator achieves a maximum motion speed of 384 μm s−1 and a maximum output force of 1.7 N. With its compact structure and light weight, the proposed actuator shows promising application prospects in the aerospace and bioengineering fields.
Single motor driven soft actuator design based on nonuniform sheering auxetic structure
Authors: Xiang Zezhi , Chen Shiye , Han Yafeng , Lu Jiping , Tang Shuiyuan , Fan Hongli , Wang Haoren , Xia Yuhan , Gong Chenglong , Wang Run , Tang Le 
Published: November 2024

Abstract
Grasping functionality is one of the core functionalities that a manipulator needs to possess. Traditional rigid manipulators are typically composed of rigid materials. However, when dealing with objects of complex shapes, irregular surfaces, or soft materials, rigid manipulators often face challenges in effectively grasping and stably holding objects due to their rigidity, which can lead to damage or failure. To address these issues, constructing manipulators using soft actuators can be highly advantageous. In most current research, soft actuators are typically composed of flexible materials and fluids, which can result in highly complex dynamic behaviors and nonlinear characteristics. This complexity makes precise modeling and control of soft actuators more challenging, necessitating the use of advanced control algorithms and techniques to mitigate nonlinear effects. In this study, we first establish a mathematical model for the torsional and bending deformations of non-uniform shearing-auxetic structures. Subsequently, we validate the reliability of the mathematical model through simulation. Finally, we design a soft actuator that requires only single-motor control, which is based on the structural design of non-uniform shearing-auxetic structures. This type of soft actuator not only simplifies control aspects but also facilitates practical modeling and manufacturing processes. Moreover, it is capable of achieving spiral grasping functionality.
Optimization of superconducting niobium nitride thin films via high-power impulse magnetron sputtering
Authors: Horne Hudson T , Hugo Collin M , Reid Brandon C , Santavicca Daniel F 
Published: November 2024

Abstract
We report a systematic comparison of niobium nitride thin films deposited on oxidized silicon substrates by reactive DC magnetron sputtering and reactive high-power impulse magnetron sputtering (HiPIMS). After determining the nitrogen gas concentration that produces the highest superconducting critical temperature for each process, we characterize the dependence of the critical temperature on film thickness. The optimal nitrogen concentration is higher for HiPIMS than for DC sputtering, and HiPIMS produces higher critical temperatures for all thicknesses studied. We attribute this to the HiPIMS process enabling the films to get closer to optimal stoichiometry before beginning to form a hexagonal crystal phase that reduces the critical temperature, along with the extra kinetic energy in the HiPIMS process improving crystallinity. We also study the ability to increase the critical temperature of the HiPIMS films through the use of an aluminum nitride buffer layer and substrate heating.
Rotation of self-generated electromagnetic fields by the Nernst effect and Righi–Leduc flux during an intense laser interaction with targets
Authors: Zhao Ziqi , Yang Xiaohu , Chen Zehao , Zhang Guobo , Ma Yanyun 
Published: November 2024

Abstract
The effect of an external magnetic field on the evolution of the self-generated electromagnetic field during laser ablation is investigated by using the Vlasov–Fokker–Planck simulations. It is found that the self-generated field is rotated and distorted under an external magnetic field, and for highly magnetized plasma, the rotation of the electric field becomes stable after the laser ablation. The theoretical analysis indicates that the rotation and tortuosity are primarily attributed to the advection of the Nernst effect and the Righi–Leduc (RL) flux. The curl of the self-generated field increases with the Hall parameter

χ

e

and reaches a peak at

χ

e

=
0.075

, then it decreases with the

χ

e

continuous increase. As the Hall parameter increases, the RL flux contributes more than 60% to the rotation of the electric field. Furthermore, the distortion of the electric field continues to rotate after the laser ablation due to the cross-gradient Nernst transport. These findings provide theoretical references for the evolution of the self-generated electromagnetic field in laser-driven magnetized plasmas.