bluuebunny/crossref_metadata_2025 huggingface dataset:
Ärztlicher Fachkräftemangel in der Rehabilitation
– Ergebnisse einer quantitativen Umfrage in deutschen
Rehabilitationsfachabteilungen
Authors: Jansen Eva Maria , Marquardt Manuela
Published: January 2024

Hintergrund  In vielen Ländern mit
hohem Einkommen herrscht ärztlicher Fachkräftemangel. Auch in
vielen Rehabilitationseinrichtungen in Deutschland bestehen Schwierigkeiten beim
Halten und Rekrutieren von Mediziner:innen. Bisher liegen keine Studien
darüber vor, welche Fachabteilungen und Einrichtungen mit welcher
Indikation und in welcher Lage davon besonders betroffen sind. Dieser Artikel
hat zum Ziel, mit einem explorativen Vorgehen empirische Anhaltspunkte zum
Phänomen ärztlicher Fachkräftemangel in
Rehabilitationsfachabteilungen zu liefern.

Materialien und Methoden  Die
Datengrundlage für die explorative Analyse stammt aus einer
Fachabteilungsumfrage aller stationärer und ambulanter
Rehabilitationseinrichtungen der Qualitätssicherungsdatenbank der DRV
(QS-REDA). Die Umfrage mit inhaltlichem Fokus auf Mediziner:innen mit
ausländischem Abschluss enthielt einen Abschnitt zum Thema
ärztlicher Fachkräftemangel, für welchen von
n=373 Fachabteilungsleitungen Angaben zuverschiedenen, mit
Fachkräftemangel assoziierten, Indikatoren vorlagen. Aus den drei
einzelnen Indikatoren (1) Vakanzzeit, (2) Fluktuationsrate und (3) Anteil
unbesetzter Stellen erstellten wir mittels Quartilssplit am 25. und 75.
Perzentil Extremgruppen (−1, 0, 1) und summierten diese zu einem Index.
Fachabteilungen mit empirischen Auffälligkeiten auf mind. 2
Einzelindikatoren wurden auf dem Fachkräftemangel-Index als
„hoch“ klassifiziert. Es werden bivariate Zusammenhänge
zwischen den Kategorien des Fachkräftemangel-Index und weiteren
strukturellen und regionalen Fachabteilungsvariablen mittels Chi-Quadrat-Tests
ausgewertet.

Ergebnisse  Die Ergebnisse der Umfrage zeigen, dass es eher
mittelgroße, peripher gelegene Einrichtungen, mit einer
stationären oder gemischten Behandlungsform und ohne die
Behandlungsschwerpunkte Orthopädie oder Rheuma sind, die unter
ärztlichem Fachkräftemangel leiden. Am stärksten ist der
Zusammenhang des Fachkräftemangel-Index mit der siedlungsstrukturellen
Typisierung der Fachabteilung (χ²(8)=34,3;
p≤0,001).

Schlussfolgerungen  Die Lage zahlreicher
Rehabilitationseinrichtungen in ländlichen Gebieten stellt eine
zusätzliche Rekrutierungsbarriere für ärztliches
Personal dar. Das Thema ärztlicher Fachkräftemangel in
Rehabilitationseinrichtungen ist bisher nicht erforscht. In Zukunft ist
abzusehen, dass die Zahl der Ärzt:innen den Bedarf noch weniger decken
wird. Um diesen auszugleichen, sind strukturierte Maßnahmen notwendig.
Die Double-Level-Derotationsosteotomie am Kniegelenk
Authors: Ferner Felix , Lutter Christoph , Perl Mario , Harrer Jörg
Published: January 2024

Die kniegelenknahe Derotationsosteotomie ist ein gängiges Verfahren zur Korrektur von kongenitalen oder posttraumatischen Torsionsdeformitäten der unteren Extremität. Klinisches Erscheinungsbild ist ein alleiniger „vorderer Knieschmerz“ oder in Kombination mit einer patellofemoralen Instabilität. Die kausale operative Therapie bei solchen Fehlstellungen stellt die Derotationsosteotomie dar. Da es sich häufig um kombinierte femorale und tibiale Fehlstellungen handelt, ist auch eine kombinierte Operationstechnik erforderlich. Diese Technik der tibialen Innentorsions- und femoralen Außentorsionsosteotomie, jeweils temporär mittels Fixateur externe und definitiv mittels Plattenosteosynthese stabilisiert, wird im aktuellen Video vorgestellt. Die tibiale Osteotomie wird hierbei mit einer Fasziotomie der Tibialis-anterior-Loge und Neurolyse des N. peronaeus kombiniert.
Anatomy and Microsurgical Relevance of the Outer Arachnoid Envelope around the Olfactory Bulb Based on Endoscopic Cadaveric Observations
Authors: Kurucz Peter , Ganslandt Oliver , Buchfelder Michael , Adib Sasan Darius , Barany Laszlo
Published: January 2024

Background There is high risk of injury to the olfactory tract and olfactory bulb during surgery of the anterior cranial fossa. The goal of this study was to describe the outer arachnoid envelope around the olfactory bulb, which plays a significant role in approach-related injury of the nerve.

Methods A total of 20 fresh human cadaveric heads were examined. Five cadaveric heads were used to describe a gross overview of the topographic anatomy of the outer arachnoid cover of the olfactory bulb. In 15 cadaveric heads, endoscopic surgical approaches were performed to examine the in situ undisrupted anatomy of the outer arachnoid around the olfactory bulb. Four cadaveric heads were used for the lateral subfrontal approach, 5 heads for the medial subfrontal approach, 3 heads for the median subfrontal approach, and 3 heads for the anterior interhemispheric approach.

Results The outer arachnoid membrane of the frontal lobe attaches the olfactory bulb strongly to the above lying olfactory sulcus. Only the most rostral portion of the olfactory bulb became slightly detached from the frontal lobe. The outer arachnoid forms a decent protrusion around the tip of the olfactory bulbs. The fila olfactoria have their own outer arachnoid cover as a continuation of the same layer of the olfactory bulb. The effect of brain retraction and manipulation forces on the olfactory bulb and the role of the arachnoid membranes located here were visually analyzed and described in detail through the four different neurosurgical approaches we performed.

Conclusion The results of our observations provide important anatomical details for preserving the sense of smell during neurosurgical procedures.
A Rare Complication of Intraprosthetic Dissociation of Cemented Bipolar Hemiarthroplasty during Closed Hip Reduction: Case Report and Literature Review
Authors: Mitchell Amanda , Belkin Nicole , Sarpong Nana , Herndon Carl L. , Hickernell Thomas R.
Published: January 2024

Hip hemiarthroplasty (HA) remains a frequently performed surgery for femoral neck fractures especially in the oldest, lowest demand patients. Debate persists concerning the optimal choice between unipolar and bipolar HA implants. A rare but important to recognize complication unique to bipolar HA is intraprosthetic dissociation (IPD). We review the literature on this rare phenomenon and identify predominant etiologies and implant components most involved in IPD, notably the role of hip dislocation and closed reduction in precipitating this complication. We also describe an elderly male patient with Parkinson's who experienced IPD of his bipolar HA during a closed reduction attempt. IPD typically requires open reduction and possibly revision of components, adding increased risk of reoperation/revision to those already frail and vulnerable to surgical complications.
A History of Gender-Affirming Surgery at the University of Michigan: Lessons for Today
Authors: Roblee Cole , Keyes Os , Blasdel Gaines , Haley Caleb , Lane Megan , Marquette Lauren , Hsu Jessica , Kuzon William M.
Published: January 2024

The University of Michigan has played an important role in advancing gender-affirming surgery programs in the United States. The University of Michigan was home to a little-known gender identity clinic shortly after the opening of the first such clinic at Johns Hopkins. Since 1995, the University of Michigan Comprehensive Services Program (UMCGSP) has been continually offering surgical services to transgender and gender diverse patients. Here, we present the history of both programs, drawn from program documents and oral history, and explore their implications for the future sustainability of gender-affirming surgery programs. The original gender identity clinic opened in 1968, and operated in a multidisciplinary fashion, similar to other clinics at the time. Eventually, the clinic was closed due to disinvestment and lack of sufficient providers to maintain the program, problems which are being increasingly recognized as barriers for similar programs. The modern program, UMCGSP is perhaps the longest continually running gender-affirming surgical program at an academic center. In spite of challenges, key investments in education, statewide community engagement, and the development of a comprehensive care model have helped UMCGSP avoid the pitfalls of the earlier clinic and remain relevant throughout its nearly 30-year history. In the face of rising challenges to gender-affirming care in the United States, much can be learned from the sustainability of the UMCGSP. Institutions seeking to maintain gender-affirming surgery programs should ensure the availability of comprehensive care and promote the education of the health care workforce.
Continuous Glucose Monitoring Feedback in the Subsequent Development of Gestational Diabetes: A Pilot, Randomized, Controlled Trial in Pregnant Women
Authors: Quah Phaik Ling , Tan Lay Kok , Lek Ngee , Tagore Shephali , Chern Bernard Su Min , Ang Seng Bin , Wright Ann , Thain Serene Pei Ting , Tan Kok Hian
Published: January 2024

Objective This study evaluated the effects of receiving glucose feedback from continuous glucose monitoring (CGM) by intermittent scanning (unblinded group), and CGM with masked feedback (blinded group) in the subsequent development of gestational diabetes mellitus (GDM).

Study Design This was a prospective, single-center, pilot, randomized controlled trial including n = 206 pregnant women in the first trimester of pregnancy with no prior diagnosis of type 1 or type 2 diabetes. The participants were randomized into the unblinded group or blinded group and wore the CGM in the first trimester of pregnancy (9–13 weeks), the second trimester of pregnancy (18–23 weeks), and late-second to early-third trimester (24–31 weeks). The primary outcome was GDM rate as diagnosed by the 75-g oral glucose tolerance test (OGTT) at 24 to 28 weeks.

Results Over 47 months, 206 pregnant women were enrolled at 9 to 13 weeks. The unblinded group had a higher prevalence of women who developed GDM (21.5 vs. 14.9%; p > 0.05), compared to the blinded group. In the unblinded group compared to the blinded group, plasma glucose values were higher at 1 hour (median 7.7 [interquartile range {IQR}: 6.3–9.2] vs. 7.5 [6.3–8.7]) and 2 hours (6.3 [5.8–7.7] vs. 6.2 [5.3–7.2]), but lower at 0 hour (4.2 [4.0–4.5] vs. 4.3 [4.1–4.6]; p > 0.05). All these differences were not statistically significant.

Conclusion Glucose feedback from CGM wear in the first to the third trimester of pregnancy without personalized patient education failed to alter GDM rate.

Key Points
Retraction Note: Importance of Religious Coping in Bereaved Parents after the Death of a Child with Genetic Disorder
Authors: Çaksen Hüseyin
Published: January 2024

Retraction

An investigation by the publisher found a number of articles, including this one, published in Journal of Pediatric Genetics in Volume 12, Number 02, 95-96, in June 2023 (DOI: 10.1055/s-0042-1759781), with a number of concerns, including but not limited to undeclared conflicts of interest and manipulated peer review procedures. As a result, the publisher has retracted and removed this article.
Retraction Note: Abortion and Protection of Fetal Life
Authors: Çaksen Hüseyin
Published: January 2024

Retraction

An investigation by the publisher found a number of articles, including this one, published in Journal of Child Science in Volume 12, Number 01, e104–e105, on September 29, 2022 (DOI: 10.1055/s-0042-1756719), with a number of concerns, including but not limited to undeclared conflicts of interest and manipulated peer review procedures. As a result, the publisher has retracted and removed this article.
Retraction Note: A Brief View of The Prophet Ayyub's (Alayhi As-Salam) Disease: Was It Job's Syndrome?
Authors: Çaksen Hüseyin
Published: January 2024

Retraction

An investigation by the publisher found a number of articles, including this one, published in Journal of Pediatric Genetics in Volume 12, Number 03, 185-186, in September 2023 (DOI: 10.1055/s-0043-1764300), with a number of concerns, including but not limited to undeclared conflicts of interest and manipulated peer review procedures. As a result, the publisher has retracted and removed this article.
The examination of the relationship between learning motivation and learning effectiveness: a mediation model of learning engagement
Authors: Lei Hong , Chen Chiwei , Luo Limei
Published: January 2024

In the past decade, China has entered the process of universalization of higher education, however, with the popularization of higher education, the issue of education quality has become more important than ever. Therefore, the main objective of this study was to explore the relationship between learning motivation and learning effectiveness, the mediation effect of learning engagement on learning motivation and learning effectiveness, and the moderation effect of students’ personality traits on the relationship between learning motivation and learning effectiveness. It was found that (1) Learning motivation had a significant positive impact on learning effectiveness; (2) Learning motivation had a significant positive effect on learning engagement; (3) Learning engagement had a significant positive impact on learning effectiveness; (4) Learning engagement had a partial mediation effect on learning motivation and learning effectiveness. (5) Personality traits had a moderation effect on the relationship between learning motivation and learning effectiveness. It was suggested that college students should stimulate their motivation for independent learning, enhance their motivation for learning, and cultivate the ability to learn independently in learning. At the same time, in the classroom, teachers should innovate teaching methods, mobilize students’ interest in learning, and cultivate students’ initiative. In addition, schools should actively carry out themed lectures to cultivate students’ correct learning attitudes. In terms of the influence of personality traits on the relationship between learning motivation and learning effectiveness should not be ignored, and appropriate attention should be paid to improving learning effectiveness. Different personality traits should be further explored.
Resilience of transportation infrastructure networks to road failures
Authors: Wassmer Jonas , Merz Bruno , Marwan Norbert
Published: January 2024

Anthropogenic climate change drives extreme weather events, leading to significant consequences for both society and the environment. This includes damage to road infrastructure, causing disruptions in transportation, obstructing access to emergency services, and hindering humanitarian organizations after natural disasters. In this study, we develop a novel method for analyzing the impacts of natural hazards on transportation networks rooted in the gravity model of travel, offering a fresh perspective to assess the repercussions of natural hazards on transportation network stability. Applying this approach to the Ahr valley flood of 2021, we discovered that the destruction of bridges and roads caused major bottlenecks, affecting areas considerably distant from the flood’s epicenter. Furthermore, the flood-induced damage to the infrastructure also increased the response time of emergency vehicles, severely impeding the accessibility of emergency services. Our findings highlight the need for targeted road repair and reinforcement, with a focus on maintaining traffic flow for emergency responses. This research provides a new perspective that can aid in prioritizing transportation network resilience measures to reduce the economic and social costs of future extreme weather events.
Mechanical forces amplify TCR mechanotransduction in T cell activation and function
Authors: Jeffreys Nicholas , Brockman Joshua M. , Zhai Yunhao , Ingber Donald E. , Mooney David J.
Published: January 2024

Adoptive T cell immunotherapies, including engineered T cell receptor (eTCR) and chimeric antigen receptor (CAR) T cell immunotherapies, have shown efficacy in treating a subset of hematologic malignancies, exhibit promise in solid tumors, and have many other potential applications, such as in fibrosis, autoimmunity, and regenerative medicine. While immunoengineering has focused on designing biomaterials to present biochemical cues to manipulate T cells ex vivo and in vivo, mechanical cues that regulate their biology have been largely underappreciated. This review highlights the contributions of mechanical force to several receptor–ligand interactions critical to T cell function, with central focus on the TCR–peptide-loaded major histocompatibility complex (pMHC). We then emphasize the role of mechanical forces in (i) allosteric strengthening of the TCR–pMHC interaction in amplifying ligand discrimination during T cell antigen recognition prior to activation and (ii) T cell interactions with the extracellular matrix. We then describe approaches to design eTCRs, CARs, and biomaterials to exploit TCR mechanosensitivity in order to potentiate T cell manufacturing and function in adoptive T cell immunotherapy.
Macroscopic behavior of populations of quadratic integrate-and-fire neurons subject to non-Gaussian white noise
Authors: Goldobin Denis S. , Permyakova Evelina V. , Klimenko Lyudmila S.
Published: January 2024

We study macroscopic behavior of populations of quadratic integrate-and-fire neurons subject to non-Gaussian noises; we argue that these noises must be α-stable whenever they are delta-correlated (white). For the case of additive-in-voltage noise, we derive the governing equation of the dynamics of the characteristic function of the membrane voltage distribution and construct a linear-in-noise perturbation theory. Specifically for the recurrent network with global synaptic coupling, we theoretically calculate the observables: population-mean membrane voltage and firing rate. The theoretical results are underpinned by the results of numerical simulation for homogeneous and heterogeneous populations. The possibility of the generalization of the pseudocumulant approach to the case of a fractional α is examined for both irrational and fractional rational α. This examination seemingly suggests the pseudocumulant approach or its modifications to be employable only for the integer values of α=1 (Cauchy noise) and 2 (Gaussian noise) within the physically meaningful range (0;2]. Remarkably, the analysis for fractional α indirectly revealed that, for the Gaussian noise, the minimal asymptotically rigorous model reduction must involve three pseudocumulants and the two-pseudocumulant model reduction is an artificial approximation. This explains a surprising gain of accuracy for the three-pseudocumulant models as compared to the two-pseudocumulant ones reported in the literature.
Effect of localization–delocalization transition on thermoelectric properties of Bi2Te2Se topological insulator
Authors: Craco L. , Leoni S.
Published: January 2024

The thermal transport properties of Bi2Te2Se topological insulators show a range of complex features. Large bulk resistivities coexisting with prominent Shubnikov–de Haas quantum oscillations and proximity to metallic states mark this p-band system as an unconventional topological quantum material. Here, using the density functional plus dynamical mean-field theory method, we show how localization–delocalization transition underpins the T-dependence of thermoelectric responses from room down to low temperatures. We present the implications of our many-particle analysis to resistivity, Seebeck coefficient, thermal conductivity, and Lorenz number and propose that related broadband systems close to electronic transitions could be of use in thermoelectrics.
In situ high-pressure pair distribution function measurement of liquid and glass by using 100 keV pink beam
Authors: Kono Yoshio , Ohara Koji , Kondo Nozomi M. , Higo Yuji , Kakizawa Sho , Yumoto Hirokatsu , Koyama Takahisa , Yamazaki Hiroshi , Senba Yasunori , Ohashi Haruhiko , Inoue Ichiro , Hayashi Yujiro , Yabashi Makina
Published: January 2024

Understanding the pressure-induced structural changes in liquids and amorphous materials is fundamental in a wide range of scientific fields. However, experimental investigation of the structure of liquid and amorphous material under in situ high-pressure conditions is still limited due to the experimental difficulties. In particular, the range of the momentum transfer (Q) in the structure factor [S(Q)] measurement under high-pressure conditions has been limited at relatively low Q, which makes it difficult to conduct detailed structural analysis of liquid and amorphous material. Here, we show the in situ high-pressure pair distribution function measurement of liquid and glass by using the 100 keV pink beam. Structures of liquids and glasses are measured under in situ high-pressure conditions in the Paris–Edinburgh press by high-energy x-ray diffraction measurement using a double-slit collimation setup with a point detector. The experiment enables us to measure S(Q) of GeO2 and SiO2 glasses and liquid Ge at a wide range of Q up to 20–29 Å−1 under in situ high-pressure and high-temperature conditions, which is almost two times larger than that of the conventional high-pressure angle-dispersive x-ray diffraction measurement. The high-pressure experimental S(Q) precisely determined at a wide range of Q opens the way to investigate detailed structural features of liquids and amorphous materials under in situ high-pressure and high-temperature conditions, as well as ambient pressure study.
Modeling of non-intrinsic noise in nanometer metal oxide semiconductor field effect transistors
Authors: Jia Xiaofei , Wei Qun , Zhang Wenpeng , He Liang , Wu Zhenhua
Published: January 2024

With the proportional reduction of metal–oxide–semiconductor field effect transistor (MOSFET) devices, the short channel effect, the parasitic effect, and the field strength effect are significantly enhanced, the proportion of parasitic resistance increases, and the non-intrinsic noise also increases, which seriously affects the working efficiency of the device. However, existing research mainly focuses on the intrinsic noise of MOSFET, and there is little research on the non-intrinsic noise; furthermore, the models describing the relationship between non-intrinsic noise, device structure, and bias have not yet been addressed. Therefore, in this paper, 90, 65, 32, 10, and 5 nm MOSFETs are studied. The rate of the intrinsic ballistic parameter is introduced to set up the source–drain current model and the non-intrinsic noise model. The source–drain current model is consistent with the theoretical model, numerical simulation, and experimental results in the literature. Finally, the relationship between the non-intrinsic noise and the bias and the device parameters are analyzed, and the conclusion is helpful to improve the working efficiency, lifetime, and response speed of nanoscale MOSFET devices.
Review on spin-split antiferromagnetic spintronics
Authors: Yan Han , Zhou Xiaorong , Qin Peixin , Liu Zhiqi
Published: January 2024

Spin splitting plays a pivotal role in most modern spintronic effects. Conventionally, spin splitting accompanied by macroscopic magnetic moments has been typically discussed in the context of ferromagnets. Nevertheless, the amalgamation of spin splitting and antiferromagnets has led to a range of intriguing magnetoelectronic effects in the field of antiferromagnetic spintronics. Considering this perspective, this Letter focuses on exploring the emerging area of spin-split antiferromagnetic spintronics. It begins with a brief overview of the historical development of the anomalous Hall effect. Subsequently, recent studies on the spin-splitting-related anomalous Hall effects in antiferromagnets are elaborated upon. Finally, a summary is provided outlining the occurrence of spin splitting in different types of antiferromagnets, including noncollinear antiferromagnets and collinear altermagnets. Additionally, the associated magnetoelectronic effects are discussed.
Extension of the law of the wall exploiting weak similarity of velocity fluctuations in turbulent channels
Authors: Hansen Christoffer , Sørensen Jens N. , Yang Xiang I. A. , Abkar Mahdi
Published: January 2024

This paper explores the similarity of the streamwise velocity fluctuations in turbulent channels. In the analysis, we employ a one-dimensional scalar variant of the proper orthogonal decomposition (POD). This approach naturally motivates the introduction of two different levels of similarity which we will refer to as strong and weak similarity. Strong similarity requires that the two-point correlation and thus, all POD modes, show Reynolds number similarity, while weak similarity only requires that the first few POD modes show similarity. As POD concerns information at more than one location, these similarities are more general than various similarities found in the literature concerning single-point flow statistics. We examine flows at Reτ=180, 540, 1000, and 5200. Strong similarity is observed in the viscous layer and the wake region, and weak similarity is found in both the viscous wall region and the outer part of the logarithmic layer. The presence of weak similarity suggests the existence of an extension to the law of the wall (LoW). We propose such an extension based on the results from the one-dimensional POD analysis. The usefulness of the LoW extension is then assessed by comparing flow reconstructions according to the conventional equilibrium LoW and the extended LoW. We show that the extended LoW provides accurate flow reconstructions in the wall layer, capturing fine-scale motions that are entirely missed by the equilibrium LoW.
Simultaneous manipulation of longitudinal and transverse elastic waves with a sharp focusing effect and customizable energy splitting ratios
Authors: Peng Huichun , Fan Lijuan , Mei Jun
Published: January 2024

Mode coupling and conversion between longitudinal and transverse modes are ubiquitous and universal in elastic waves, presenting a challenge in realistic applications such as nondestructive evaluation and geological exploration, where independent and separate manipulation of each mode is demanded. In this article, we propose a design of elastic metalens that can realize a high-efficiency focusing for the longitudinal wave and a V-shaped converging pattern for the transverse wave at the same time. The metalens is constructed from a metagrating, where each meta-atom has a simple configuration and renders high diffraction efficiency even for large steering angles, enabled by concurrent utilization of grating diffraction theory and advanced optimization algorithms. Interestingly, an arbitrary energy splitting ratio between the reflected longitudinal and transverse waves can be obtained by precisely controlling the coupling strength and conversion efficiency between them, providing improved flexibility and adaptability to various application environments. Two illustrative examples with a sharp focusing effect and tailored conversion efficiency are explicitly demonstrated, with a 50/50 energy splitting ratio between the longitudinal and transverse waves in the first case, and a 70/30 ratio in the second one.
Thermosolutal convection in a Brinkman–Darcy–Kelvin–Voigt fluid with a bidisperse porous medium
Authors: Badday Alaa Jabbar , Harfash Akil J.
Published: January 2024

A model for thermosolutal convection of a category of viscoelastic fluids in a bidisperse porous medium is comprehensively investigated. The Brinkman model is employed in macropores, whereas the Darcy model is utilized in micropores. In the momentum equations, the densities are considered a linear function of temperature and concentration. The concentration of solutes at equilibrium is assumed to be a linear function of temperature. There are two situations considered, where we have study systems that are heated below and salted above and heated and salted below. The fluids are of the Kelvin–Voigt type. The critical Rayleigh numbers for linear instability and nonlinear stability are computed.
Anatomy of the dielectric behavior of methyl-m-toluate glasses during and after vapor deposition
Authors: Richert R. , Tracy M. E. , Guiseppi-Elie A. , Ediger M. D.
Published: January 2024

Glassy films of methyl-m-toluate have been vapor deposited onto a substrate equipped with interdigitated electrodes, facilitating in situ dielectric relaxation measurements during and after deposition. Samples of 200 nm thickness have been deposited at rates of 0.1 nm/s at a variety of deposition temperatures between 40 K and Tg = 170 K. With increasing depth below the surface, the dielectric loss changes gradually from a value reflecting a mobile surface layer to that of the kinetically stable glass. The thickness of this more mobile layer varies from below 1 to beyond 10 nm as the deposition temperature is increased, and its average fictive temperature is near Tg for all deposition temperatures. Judged by the dielectric loss, the liquid-like portion of the surface layer exceeds a thickness of 1 nm only for deposition temperatures above 0.8Tg, where near-equilibrium glassy states are obtained. After deposition, the dielectric loss of the material positioned about 5–30 nm below the surface decreases for thousands of seconds of annealing time, whereas the bulk of the film remains unchanged.
Segregation of Al and its effect on coercivity in Nd-Fe-B
Authors: Liu X. B. , Nlebedim I. C.
Published: January 2024

Doping a small amount of Al can effectively enhance coercivity in Nd-Fe-B magnets. We investigated the partitioning behavior of Al and its effect on coercivity in Nd-Fe-B using first principles DFT (density functional theory) calculation and micromagnetic simulation. The calculated substitution energies of Fe by Al are negative at the crystallographic sites of 4c and 8j2 while they are positive values at the other sites in Nd2Fe14B (2:14:1), implying a small solubility of Al in 2:14:1. Further, Al prefers to segregate at grain boundary (GB) and stabilize the Nd-Fe-Al phase with a Nd6Fe13Si-type tetragonal structure (6:13:1). The formation of the antiferromagnetic or weak ferrimagnetic 6:13:1-like phase depletes Fe and reduces the amount of ferromagnetic Nd–Fe type grain boundary phase (GBP), which weakens the inter-grain magnetic interaction. Micromagnetic simulations indicate that the 6:13:1-like GBP increases the pinning field of magnetic domain wall at GB and suppresses the nucleation of reversal magnetic domain on the grain surface of 2:14:1 during demagnetization process. The formation of Al-rich shell on 2:14:1 grain surface can further moderately increase the domain pinning field at GB and the nucleation field of 2:14:1 grain. Developing novel processing method to tailor Al segregation and promote formation of 6:13:1-like phase at GB can be a promising approach to improve coercivity in Nd-Fe-B magnet.
On trajectory control of magnetized spherical solids driven by magnetic force through soft medium
Authors: Malkova Yulia , Guez Allon , Friedman Gary
Published: January 2024

Manipulation of untethered millimeter-sized devices (bots) inside the human body has many medical applications. Most of the prior work focused on movement of such bots inside fluids, usually at low Reynolds numbers. Yet, many medical procedures are performed within soft tissues. Bot translation in soft materials differs dramatically from their motion in fluid. This paper focuses on trajectory control of small, untethered spheres driven magnetically in soft media commonly used to simulate tissues. While spherical bot shapes offer the advantage of potentially rapid change in the direction of motion, the main challenge in controlling trajectories through soft materials is their nonlinear and history dependent response forces associated with irreversible medium modification. This paper introduces control modules for manipulating spherical bots in soft media along elementary trajectories of circular and straight segments, from which more general trajectories may be assembled. The proposed control is based on a phenomenological model of soft media response forces. Numerical implementation of the proposed trajectory control along circular trajectories is shown to compare well with the results of experimental tests indicating that the accuracy on the order of the bot radius is readily achievable for trajectories whose radii of curvature is on the order of 10 bot radii.
Improved design and analysis for electromagnetic performance of magnetic geared permanent magnet machine according to winding pattern and segmentation of permanent magnet
Authors: Yu Kyeong-Tae , Ban Hwi-Rang , Lee Ju-Hyeong , Choi Jang-Young , Sung Soyoung , Park Jung-Hyung , Shin Kyung-Hun
Published: January 2024

This paper presents an analysis of the operating principle of magnetic geared permanent magnet machines (MGPMMs), electromagnetic analysis results according to the winding pattern, and a method for improving power factor and loss characteristics. To improve electromagnetic performance, the air gap magnetic flux density was calculated using the finite element method, and the harmonics of the inner and outer air gap magnetic flux densities was analyzed using the fast Fourier transform (FFT). From the FFT results, harmonic orders that affect electromagnetic performance were presented, and the electromagnetic analysis results were compared to derive correlations with torque ripple and losses. In addition, a design method for improving electromagnetic performance and operating characteristics was proposed by comparing power factors according to winding pattern. In particular, to improve the robust design and efficiency of MGPMM, a method of reducing eddy current loss by segmenting permanent magnets was addressed. The proposed analysis and design method can be widely used in the design and characteristic analysis of MGPMM.
Use of consolidated time-lapse camera imagery to detect and monitor platypus (Ornithorhynchus anatinus) activity
Authors: Roberts Simon , Serena Melody
Published: January 2024

The platypus is a challenging species to survey and monitor. We investigated the use of time-lapse cameras to detect platypus activity in a Tasmanian creek by deploying three camera models diurnally at a single site over 6 months, and deploying one model both nocturnally and diurnally at two sites over 12 months. Variation in camera attributes and settings (camera view angle, length of time-lapse intervals) contributed to a 10-fold difference in the mean number of platypus images recorded in a given behavioural sequence (or ‘event’) and an approximately 50% difference in median event duration among the three models. Results also varied between sites and at diel and bimonthly time scales due to pool topography, day length (affecting site illumination) and likely temporal differences in platypus activity and population size. However, even the least-effective camera model reliably captured ≥1 platypus image within the first 24 h of deployment at the two study sites throughout the year. Time-lapse cameras are a suitable tool to assess platypus occurrence and measure activity, as long as appropriate equipment is selected for the intended purpose and sources of spatial and temporal variation are carefully considered when designing studies and interpreting results.
Reconstruing the image of Shan Gui
Authors: Wang Xi , Jiang Rong
Published: January 2024

This study aims to investigate the image reconstrual of Shan Gui 山鬼 in the multimodal translation from the poem Shan Gui to three renowned
paintings, i.e., Li Gonglin’s 李公麟 (date unknown;
1049–1106), Fu Baoshi’s 傅抱石’s (1945) and Xu Beihong’s
徐悲鸿 (1943), within the framework of social semiotics,
and to explore the reason why the image changed through recontextualization. It is found that the image of Shan Gui reconstrued by
Li looks like a detached sprite; Fu is a sentimental goddess, while Xu is a mundane human girl. Contextual factors, including
scholastic explanations of the poem, the individual orientation of painters, and their media choices, contribute to such image
divergence.
Fast-evolving cofactors regulate the role of HEATR5 complexes in intra-Golgi trafficking
Authors: Marmorale Lucas J. , Jin Huan , Reidy Thomas G. , Palomino-Alonso Brandon , Zysnarski Christopher J. , Jordan-Javed Fatima , Lahiri Sagar , Duncan Mara C.
Published: January 2024

The highly conserved HEATR5 proteins are best known for their roles in membrane traffic mediated by the adaptor protein complex-1 (AP1). HEATR5 proteins rely on fast-evolving cofactors to bind to AP1. However, how HEATR5 proteins interact with these cofactors is unknown. Here, we report that the budding yeast HEATR5 protein, Laa1, functions in two biochemically distinct complexes. These complexes are defined by a pair of mutually exclusive Laa1-binding proteins, Laa2 and the previously uncharacterized Lft1/Yml037c. Despite limited sequence similarity, biochemical analysis and structure predictions indicate that Lft1 and Laa2 bind Laa1 via structurally similar mechanisms. Both Laa1 complexes function in intra-Golgi recycling. However, only the Laa2–Laa1 complex binds to AP1 and contributes to its localization. Finally, structure predictions indicate that human HEATR5 proteins bind to a pair of fast-evolving interacting partners via a mechanism similar to that observed in yeast. These results reveal mechanistic insight into how HEATR5 proteins bind their cofactors and indicate that Laa1 performs functions besides recruiting AP1.
CCEM key comparison CCEM.RF-K26. Attenuation at 18 GHz, 26.5 GHz and 40 GHz using a step attenuator. Final report of the pilot laboratory
Authors: Widarta A
Published: January 2024

Main text

This report summarizes the results of the Key Comparison CCEM.RF-K26 Attenuation at 18 GHz, 26.5 GHz and 40 GHz using a step attenuator which has been performed from January 2015 to February 2018. Fourteen National Metrology Institutes (NMIs) participated in this key comparison, including the National Metrology Institute of Japan (NMIJ/AIST, Japan) which served as pilot laboratory, the National Institute of Metrology (NIM, China), the Physikalisch-Technische Bundesanstal (PTB, Germany), the Laboratoire national de métrologie et d'essais (LNE, France), the Swiss Federal Office for Metrology and Accreditation (METAS, Switzerland), the National Physical Laboratory of India (NPLI, India), the All-Russian Scientific Research Institute of Physico-Technical Measurements (VNIIFTRI, Russia), the Korea Research Institute of Standard and Science (KRISS, South Korea), the National Physical Laboratory (NPL, United Kingdom), the National Metrology Institute of South Africa (NMISA, South Africa), the Tubitak Ulusal Metrologi Enstitűsű (TUBITAK-UME, Turkey), the National Metrology Centre (NMC-A*STAR, Singapore), the Czech Metrology Institute (CMI, Czech Republic) and the Instituto Nacional de Tecnica Aeroespacial (INTA, Spain). The Key Comparison Reference Values (KCRVs) were determined from the measurement results of five to ten participating NMIs, depending on the attenuation and frequency.

To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/.

The final report has been peer-reviewed and approved for publication by the CCEM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
Highly parallelizable electronic transport calculations in periodic rhodium and copper nanostructures
Authors: Feldman Baruch , Zhu Shifeng , Dunham Scott
Published: January 2024

We extend the highly-parallelizable open-source electronic transport code TRANSEC (Feldman et al 2014 Phys. Rev. B 90 035445; https://gitlab.com/computational-physics2/transec/) to perform real-space atomic-scale electronic transport calculations with periodic boundary conditions in the lateral dimensions. We demonstrate the use of TRANSEC in periodic Cu and Rh bulk structures and in large periodic Rh point contacts, in preparation to perform calculations of reflection probability across Rh grain boundaries.
Feedback enhanced Dyakonov–Shur instability in graphene field-effect transistors
Authors: Cosme Pedro , Simões Diogo
Published: January 2024

Graphene devices are known to have the potential to operate THz signals. In particular, graphene field-effect transistors (gFETs) have been proposed as devices to host plasmonic instabilities in the THz realm; for instance, Dyakonov–Shur (DS) instability which relies upon dc excitation. In this work, starting from a hydrodynamical description of the charge carriers, we extend the transmission line description of gFETs to a scheme with a positive feedback loop, also considering the effects of delay, which leads to the transcendental Laplace-transform transfer function, with complex frequency s, with terms of the form

e

−
a
s

s
e
c
h

k

(
s
)

/

s

, for a given

a
∈

R

0
+

arising from the delay time and with

k
∈

N

. Applying the conditions for the excitation of DS instability, we report an enhanced voltage gain in the linear regime that is corroborated by our simulations of the nonlinear hydrodynamic model for the charge carriers. This translates to both greater saturation amplitude—often up to 50% increase—and faster growth rate of the self-oscillations. Thus, we bring forth a prospective concept for the realization of a THz oscillator suitable for future plasmonic circuitry.
Development of a modular system to provide confidence in porosity analysis of additively manufactured components using x-ray computed tomography
Authors: Chahid Y , Packer C , Tawfik A , Keen J , Brewster N , Beardsley M , Morris K , Bills P , Blunt L , Atkins C , Tammas-Williams S
Published: January 2024

X-ray computed tomography (XCT) offers a promising non-destructive method to assess high value components that are additively manufactured (AM) for space-based imaging. However, AM components can be often challenging to measure and the true resolution of the XCT system used is both non-trivial to determine and may change locally. To solve this, we used high precision micro-machining to manufacture a cylindrical reference pin with internal holes. This pin can then be inserted into any component via subtractive machining, prior to the XCT process. A pre-existing AM flexure is modified to allow our modular system to be implemented. This allows XCT scanning and porosity analysis of similar components (similar geometry and manufacturing process) to be refined and adjusted based on the known internal micro-machined hole size. Analysis of the XCT volumetric data is implemented using a Python script developed for Avizo 2022.1, to compare and suggest the ideal threshold grey value (GV). The plugin threshold comparison is semi-automatic and 15 times faster than a manual comparison. Study findings showed how different calibrated micro-machined hole sizes (30 μm–120 μm) needed different thresholding values (188 GV–195 GV). Challenges and future studies related to traceability of the suggested method are discussed.
Multi-condition stability analysis and lightweight research of mining wide-body dump truck compartment
Authors: Liu Zhihai , Liu Dongyang , Tian Shaolu , Han Wenyu , Zhao Xieguang
Published: January 2024

This paper proposes a multi-condition optimization method based on single condition optimization and weight. This method analyzes and discusses various working states of the wide-body dump truck and optimize its structure. Firstly, the modal shape and natural frequency of the carriage under modal conditions are analyzed using the finite element method. Combined with the mechanic’s theory, the carriage’s force, deformation, and stress are studied under the turning and partial load conditions. This part provides a basis for subsequent stability analysis and lightweight research. According to the filtering white noise method and differential equation method, the f-class road model and the vehicle system dynamics model are established in MATLAB to study the influence of road vibration on the stability of the dump truck during operation. The carriage vibration data prove that the road vibration causes the low order resonance of the carriage and affects the stability of the dump truck. This part provides a basis for the subsequent stability optimization. Based on the above analysis, a multi-objective genetic algorithm based on the response surface is used to optimize the structural parameters of the carriage under partial load conditions, turning conditions and modal conditions, to realize the optimization of stability, mass, stress and deformation of the carriage. Finally, the entropy weight method is used to fuse the optimization results of the three working conditions. The correctness of the comprehensive optimization results is verified, and the wide-body dump truck carriage optimization is realized, proving the feasibility of the proposed method.
The anisotropic transport properties of the three-terminal ballistic junction based on α−T
3 lattice
Authors: Xiao Ningyan , Duan Xian , Zhang Siyan , Zhou Benliang , Zhou Benhu
Published: January 2024

The three-terminal ballistic junction (TBJ) has promising applications in nanoelectronics. We investigate the transport properties of a α−T
3-based TBJ, where two typical configurations are considered, i.e. the A- and Z-TBJ. It is found that both A- and Z-TBJ exhibit transmission anisotropy, and the transmission of the A-TBJ has stronger anisotropy than that of the Z-TBJ. The amplitude of the rectification coefficient is smaller than that of phosphorene TBJ, but larger than that of graphene TBJ. When the symmetrical input is applied, the output voltage curve exhibits symmetric behavior. While in the case of asymmetric input, the symmetric behavior is broken, and the maximum value of the output voltage can reach a positive value. Interestingly, the voltage output shows a dramatic nonlinear response which may be useful for the voltage diode application with a push-pull input voltage. In addition, the heat fluxes of the asymmetric input are much smaller than those of the symmetric input. The maximum value of the heat flux under the symmetric input exceeds twice of that under the asymmetric input. Our results are useful to design nanoelectronic devices based on α−T
3 TBJ.
Structural stability of subsonic steady states to the hydrodynamic model for semiconductors with sonic boundary
Authors: Feng Yue-Hong , Hu Haifeng , Mei Ming
Published: January 2024

The hydrodynamic model for semiconductors with sonic boundary, represented by Euler–Poisson equations, possesses the various physical steady states including interior-subsonic/interior-supersonic/shock-transonic/C
1-smooth-transonic steady states. Since these physical steady states result in some serious singularities at the sonic boundary (their gradients are infinity), this makes that the structural stability for these physical solutions is more difficult and challenging, and has remained open as we know. In this paper, we investigate the structural stability of interior subsonic steady states. Namely, when the doping profiles are as small perturbations, the differences between the corresponding subsonic solutions are also small. To overcome the singularities at the sonic boundary, we propose a novel approach, which combines the weighted multiplier technique, local singularity analysis, monotonicity argument and squeezing skill. Both the result itself and the technique developed here will give us some truly enlightening insights into our follow-up study on the structural stability of the remaining types of solutions. A number of numerical approximations are also carried out, which intuitively confirm our theoretical results.