bluuebunny/crossref_metadata_2025 huggingface dataset:
MRT bei kindlichen Kopfschmerzen
Authors: Marie Anders Rebecca , Roth Christian
Published: August 2024

Bei einem primären Kopfschmerz ist eine Bildgebung in der Regel nicht indiziert. Darunter fallen u. a. Migräne und Spannungskopfschmerzen, mit typischer Symptomatik. In solchen Fällen ist in der MRT-Bildgebung mit hoher Wahrscheinlichkeit kein pathologischer Befund zu erwarten.

Kopfschmerzen, die nicht in diese Kategorie fallen, können sogenannte sekundäre Kopfschmerzen mit einer dem Kopfschmerz zugrundeliegenden Pathologie sein, die dann häufig auch im MRT sichtbar ist. Hierzu zählen z. B. atypische Kopfschmerzen, die sehr plötzlich aufgetreten sind oder in deren Verlauf sich relevante Veränderungen beobachten ließen. Andere, sogenannte “red flags”, die zu einer MRT-Abklärung führen sollten, sind neurologische Symptome, die den Kopfschmerz begleiten, wie auch afebrile Krampfanfälle oder Papillenveränderungen (Stauungspapille).

Ein dabei auftretendes relevantes Problem sind inzidentelle Befunde in der MRT-Bildgebung, wie unspezifische Gliosen oder venöse Anomalien (DVA). Diese haben meistens keinen Zusammenhang mit Kopfschmerzen, führen aber – wenn einmal beschrieben – zu Beunruhigung. Eine ausführliche und gute Kommunikation über solche, meist harmlosen Befunde ist notwendig, schon vor der Untersuchung im Aufklärungsgespräch. Folgeuntersuchungen sind dann – wenn klinisch vertretbar – zu vermeiden.

Manche anhaltenden Kopfschmerzen verunsichern aber Kinder und Eltern so stark, dass nur aus diesem Grunde eine MRT-Bildgebung erwogen wird. Beunruhigung allein – ohne die genannten red flags – ist aber keine ausreichende medizinische Indikation. Die Durchführung solcher MRT-Untersuchungen ist daher umstritten. Eine generelle Ablehnung solcher Untersuchungen ist in der Praxis aber kaum zu realisieren, Kinderarzt und Kinderradiologe werden hier weiter mit einer Indikationsgrauzone leben müssen.
Technische Entwicklungen in der pädiatrischen MRT-Diagnostik
Authors: Kellenberger Christian J , Kottke Raimund , Sirin Selma
Published: August 2024

Die Magnetresonanztomografie (MRT) wird in der Kinderradiologie zunehmend zur definitiven Diagnosestellung, Therapieplanung oder Verlaufskontrolle nach Behandlung genutzt. In spezialisierten pädiatrischen Zentren wird die strahlungsfreie MRT meist der auf Röntgenstrahlen basierenden Computertomografie (CT) vorgezogen und hat mancherorts nuklearmedizinische Untersuchungen wie die Skelett- und Nierenszintigrafie ersetzt. Durch die fortschreitenden Entwicklungen der MR-Technologie in den letzten Jahren sind heute in allen Körperregionen relativ kurze Untersuchungen zur hervorragenden morphologischen Darstellung von Veränderungen der Weichteile und Organe möglich. Durch Synchronisierung der MR-Datenerfassung mit dem Herzschlag oder der Atmung können das Herz, die Lunge oder abdominale Organe ohne Atemartefakte abgebildet werden, auch bei kleinen Kindern, die den Atem nicht anhalten können. Mit schnellen Sequenzen können auch nicht ganz stillhaltende Kinder untersucht werden. Im Gegensatz zur CT liefert die MRT neben morphologischen auch funktionelle Informationen. So können mit speziellen MR-Sequenzen z. B. die Organperfusion, die Gefäßdurchblutung, die Nierenausscheidung oder die Herzfunktion evaluiert werden.
Bildgebende Diagnostik der kindlichen Lunge mit MRT und CT
Authors: Veldhoen Simon , Metz Corona
Published: August 2024

Obwohl die Röntgenaufnahme des Thorax nach wie vor das bildgebende Standardverfahren in der pädiatrischen Lungendiagnostik ist, werden die schnittbildgebenden Techniken für spezielle Fragestellungen auch im Kindes- und Jugendalter regelhaft benötigt. Durch beträchtliche technologische Fortschritte haben sich die Möglichkeiten der Lungenbildgebung mittels CT und MRT deutlich erweitert. Wenngleich Strahlenexposition und Untersuchungszeiten von CT-Untersuchungen drastisch gesenkt werden konnten, sind eine akkurate Nutzen-Risiko-Abwägung und die Erwägung strahlenfreier Alternativmethoden weiterhin von großer Wichtigkeit. In diesem Zusammenhang kommt die strahlenfreie MRT, die neben der morphologischen Darstellung der Lunge inzwischen auch funktionelle Informationen liefern kann, zunehmend zum Einsatz. Pädiatrische Schnittbildgebung, insbesondere die zeitintensivere MRT, erfordert bei jüngeren Kindern häufig eine Untersuchungsführung in Narkose. Gezielte Konzepte zur Schaffung einer kindgerechten Untersuchungsumgebung in spezialisierten kinderradiologischen Einrichtungen leisten einen Beitrag dazu, die Patientenerfahrung zu optimieren und Narkoseuntersuchungen zu reduzieren.
Jubiläums-Kongress mit emotionaler Rückschau und Blick in die Zukunft
Authors: Schöllmann Claudia
Published: August 2024

Es war ein besonderer Jahreskongress der European Society for Blood and Marrow Transplantation (EBMT), der Mitte April 2024 in Glasgow, Schottland, UK, stattfand. Die Fachgesellschaft feierte mit dem Meeting nicht weniger als ihr 50-jähriges Bestehen. Mit Prof. Eliane Gluckman, Paris, Frankreich, war sogar das einzige noch lebende Gründungsmitglied aus dem Jahr 1974 vor Ort. Die „große alte Dame“ der Hämatologie und Blutzelltransplantation erinnerte in einem emotionalen Vortrag an eine „Reise von Innovation und Hoffnung“ über 5 Dekaden, an Herausforderungen gerade in den ersten Jahren, aber auch viele Therapiedurchbrüche, die in 2 Nobelpreisen in den Jahren 1980 und 1990 mündeten. Auf dem Jubiläumskongress wurden auch zahlreiche neue Daten vorgestellt, die den Blick in die Zukunft richteten.
Bispezifischer Immuncheckpoint-Inhibitor Cadonilimab verbessert Gesamtüberleben
Authors: Kretzschmar Alexander
Published: August 2024

Der bispezifische Immuncheckpoint-Inhibitor Cadonilimab (AK104) verbesserte in Kombination mit einer Chemotherapie das mediane Gesamtüberleben (OS) in der Erstlinientherapie bei Patient*innen mit nicht resezierbarem, lokal fortgeschrittenem oder metastasiertem Adenokarzinom des Magens bzw. des ösophagogastralen Übergangs (AEG) unabhängig vom PD-L1-Expressionsstatus. Dies zeigt eine auf der Jahrestagung der American Association for Cancer Research (AACR) vorgestellte Interimsauswertung der Phase-III-Studie COMPASSION 15 (NCT05008783).
Der PROphet sagt das Outcome beim NSCLC voraus
Authors: Kretzschmar Alexander
Published: August 2024

Immuncheckpoint-Inhibitoren haben die Therapie des NSCLC verändert. Allerdings sucht man noch nach validierten Biomarkern zur Prognose und Therapiesteuerung. Bei der Jahrestagung der AACR wurde gezeigt, dass mit einer Proteom-Profiling-Plattform mithilfe von Plasmaproben eine Vorhersage des klinischen Erfolges als auch der Risiken immunassoziierter unerwünschter Ereignisse (irAE) möglich ist. Die Auswertung übernahm der mit maschinellem Lernen arbeitende Algorithmus PROphet.
Kardiovaskuläres Risiko nach Mammakarzinomdiagnose und -therapie
Authors: Lorenz Judith
Published: August 2024

Die modernen Screening- und Therapiemöglichkeiten haben die Überlebenschancen nach einer Mammakarzinomdiagnose deutlich verbessert. Allerdings wird befürchtet, dass der Tumor und/oder die onkologische Therapie kardiovaskuläre Ereignisse begünstigen. Wie häufig erleiden asiatischstämmige Mammakarzinompatientinnen eine Koronarerkrankung oder einen Schlaganfall? Dieser Frage ging eine retrospektive Kohortenstudie aus Taiwan nach.
Fachübergreifendes Programm und wissenschaftlicher Austausch
Authors: Sankawa Yuri
Published: August 2024

Der European Lung Cancer Congress (ELCC) 2024 bot ein multidisziplinär angelegtes Programm zu Themenschwerpunkten rund um die Thoraxonkologie, das neben hochwertigen edukativen Inhalten im Bereich Prävention, Diagnostik und der State of the Art der Lungenkrebsbehandlung auch viele Gelegenheiten zum fachübergreifenden wissenschaftlichen Austausch umfasste. Gezählt wurden über 2800 Teilnehmer*innen aus mehr als 80 Ländern, die den Kongress on-site oder online besuchten.
Neue(re) Techniken in der Pädiatrischen Sonografie
Authors: Mentzel Hans-Joachim
Published: August 2024

Die Sonografie ist häufig erstes und in der konservativen und operativen Kinder- und Jugendmedizin auch einziges bildgebendes Verfahren in der Diagnostik. Neue(re) Techniken wie die verschiedenen Methoden der Kontrastmittelsonografie, der Elastographie und des Quantitativen Ultraschalls unterstreichen diesen Anspruch. Sie erhöhen aber auch den Energieeintrag in den Organismus. Die Anwendung erfordert daher entsprechende Sorgfalt und eine rechtfertigende Indikation. Mit Einsatz innovativer Ultraschall-Anwendungen können Kindern andererseits aufwändigere Untersuchungen erspart werden wie eine Magnetresonanztomografie in Sedierung/Narkose oder eine Computertomografie mit einer nicht unerheblichen Dosis an ionisierender Strahlung. Ziel des Beitrages ist ein kurzer Überblick zu den Techniken. Anwendungen werden an Fallbeispielen gezeigt.
Was brauche ich wann in der kinderorthopädischen Bildgebung?
Authors: von Kalle Thekla
Published: August 2024

Neben Anamnese und klinischer Untersuchung ist die Bildgebung eines der wichtigsten Standbeine der kinderorthopädischen Diagnostik. Radiologische Untersuchungen dienen sowohl der Diagnosestellung als auch der Quantifizierung und Verlaufskontrolle pathologischer Veränderungen. Mit ihrer Hilfe werden operative Maßnahmen geplant und deren Ergebnisse überprüft. Radiologisch technische Besonderheiten erfordern eine spezielle kinderradiologische Expertise genauso wie die altersabhängigen Normvarianten und Erkrankungen des sich noch entwickelnden muskuloskelettalen Systems. Ergebnisse der Bildgebung sind dabei immer im klinischen Kontext zu sehen, denn nur so kann es gelingen, hinter einem einzelnen Befund ein Syndrom oder eine chronische Grunderkrankung zu erkennen. Kurze Wege und niederschwellige interdisziplinäre Kommunikation zwischen Radiologie und Orthopädie sind essenziell, um unseren jungen Patienten gerecht zu werden.
Besonderheiten rheumatischer Erkrankungen im Alter
Authors: Schultz Olaf
Published: August 2024

Aufgrund der erhöhten Lebenserwartung und anhand epidemiologischer Daten zeigt
sich eine Zunahme rheumatische Erkrankungen älterer Menschen. Diese Population
ist durch ein erhöhtes Risiko für kardiovaskuläre, infektiöse, neoplastische und
iatrogene Komplikationen betroffen. Multimorbidität in Verbindung mit
Polypharmazie und progredienten funktionellen Defiziten haben erheblichen
Einfluss auf den klinischen Verlauf und die Therapieentscheidungen bei
Altersvarianten rheumatischer Erkrankungen. Der Altersprozess des Immunsystems
ist geprägt von Immunseneszenz und „Inflammaging“ mit der Folge eines erhöhten
Risikos für Infektionen und Tumorerkrankungen, eines verringerten regenerativen
Potentials und einer verstärkten unspezifischen Entzündungskonstellation. Neben
den wenigen alterstypischen rheumatischen Erkrankungen wie der Polymyalgia
rheumatica gibt es Altersformen rheumatischer Erkrankungen, die hinsichtlich der
klinischen Symptomatik, der Pathophysiologie, Labordiagnostik und der Prognose
Besonderheiten aufweisen. Atypische Krankheitsverläufe und Mischbilder mit
degenerativen oder anderen entzündlichen Erkrankungen sind nicht ungewöhnlich.
In der Übersichtsarbeit werden die speziellen Altersvarianten verschiedener
rheumatischen Erkrankungen vorgestellt. Ältere Patienten mit rheumatischen
Erkrankungen sind durch die derzeitige Studienlage nicht adäquat erfasst. Ein
wesentlicher Schwerpunkt künftiger klinisch-rheumatologischer Forschung sollte
die stärkere Einbeziehung dieser Patienten sein, um durch angepasste und
integrative Therapiekonzepte Morbidität und Mortalität zu reduzieren.
Recent Advances in the Chemistry and Application of SF5-Compounds
Authors: Bizet Vincent , Abd El Sater Mariam , Popek Lucas , Blanchard Nicolas
Published: August 2024

This review article outlines the literature from 2022 to 2024 covering developments in SF5 chemistry. Recent synthetic methodologies of SF5-containing building blocks are reported. These methods include the synthesis of SF5Cl and its use in pentafluorosulfanylation reactions and oxidative fluorination reactions. Moreover, the reactivity of SF5-alkynes as versatile platform to access new SF5-compounds is described. Finally, the effects of the SF5 moiety are highlighted according to its application in different fields, such as biological/medicinal chemistry, catalysis, and material sciences.

1 Introduction

2 Access to SF5-Containing Building Blocks

2.1 By Means of SF5Cl

2.1.1 Generation of SF5Cl

2.2 By Means of Oxidative Fluorination

2.3 By Means of SF5-Alkynes

2.4 Other Miscellaneous Aromatic and Aliphatic SF5-Compounds

3 Applications

3.1 Medicinal and Biological Chemistry

3.2 Material Science

3.3 Catalysis

4 Conclusion
Catalytic Intermolecular [4+2]-Cycloaddition toward the Stereo­selective C2–C3 Annulation of Indoles
Authors: Majumdar Nilanjana , Pandit Soumen
Published: August 2024

Catalytic dearomative cycloaddition involving the C2–C3 bond of indoles is a powerful strategy for the synthesis of fused indoline scaffolds. Through dearomative cycloaddition/annulation, planar indole substrates can be readily transformed into rigid, three-dimensional polycyclic complex structures in one step. Molecules with architectural complexity are generally considered to have drug-like properties. Hence, annulation products have tremendous potential for discovering therapeutic properties, and this strategy has become an important part of the medicinal chemistry toolbox. Using appropriate catalyst control, desirable stereoselectivity can be achieved. Previous literature reports reveal that [3+2]-cycloadditions of indoles have been extensively studied. In contrast, the catalytic [4+2]-cycloaddition/dearomatization of indoles has been much less investigated. In this short review, we focus specifically on six-membered ring annulations via [4+2]-cycloaddition with the C2–C3 bond of indoles and discuss the various catalytic methods that have been developed toward this objective.

1 Introduction

2 [4+2]-Cycloaddition/Annulation of Indoles

2.1 Electron-Rich Indoles

2.1.1 Transition-Metal Catalysis

2.1.2 Organocatalysis

2.2 Electron-Deficient Indoles

2.2.1 Transition-Metal Catalysis

2.2.2 Organocatalysis

3 Summary and Outlook
Malformations of the Spinal Cord: From Genetics to Diagnosis and Rehabilitation
Authors: Cacciaguerra Giovanni , Dierna Federica , Zanghì Antonio , Vecchio Michele , Praticò Elena R. , Rosa Giuliana La , Palmucci Stefano , Belfiore Giuseppe , Basile Antonio , Ruggieri Martino , Polizzi Agata
Published: August 2024

Spinal cord malformations, known as “spinal dysraphisms” encompass a diverse range of spinal abnormalities characterized by incomplete median closure of mesenchymal, bone, and nervous tissues. They are classified as “open,” involving both the spinal cord and overlying tissues, or “occult,” affecting only nervous system structures. Neurulation abnormalities along the neural tube, from the rostral to the caudal portions, primarily cause these malformations. Clinical presentations vary, including cutaneous manifestations like hemangiomas, dimples, hair tufts, and scoliosis. “Tethered cord syndrome,” often associated with these malformations, manifests as a clinical syndrome rather than a primary anomaly. Newborns are typically asymptomatic, with malformations often identified by associated skin abnormalities. Older children may experience pain, sensory/motor disturbances, urinary/anal sphincter abnormalities, and muscle weakness affecting mobility. Neuroimaging, crucial for diagnosis and treatment planning, includes ultrasound, CT, and MRI. Surgical intervention, tailored to specific malformation subtypes, may involve the repair of myelomeningocele soon after birth or conservative management for asymptomatic occult dysraphism. Rehabilitation encompasses physical, occupational, recreational, and speech therapies. Prevention is paramount, emphasizing the role of health care professionals in prenatal care and education. This review aims to provide a systematic classification of spinal cord malformations to aid clinicians in diagnosis and management.
Evolution of filament-like compact structures in small 3 kJ dense plasma focus discharges
Authors: Kubes P. , Marciniak L. , Sadowski M. J. , Paduch M. , Cikhardtova B. , Cikhardt J. , Kravarik J. , Malir J. , Munzar V. , Novotný J. , Rezac K.
Published: August 2024

This paper presents the filamentary structure of the pinched column in a smaller plasma focus device filled with deuterium. The deflections were observed using schlieren and differential interferometry techniques. The observed filaments have a transverse diameter of 40–200 μm, which could be interpreted based on the electric current hypothesis as local concentrations of electric current. The evolution of filaments was compared with global structures recorded by extra ultraviolet frames. These results provide a basis for considering the possibility of a filamentary composition of the poloidal current in compact structures. The model of filaments with a helical shape of electrical current may be able to explain the central narrow and dense cord in the axis of the column, the different lifetimes of the structures, and the submillimeter sources of fast electrons and ions.
Deep learning-based characterization of ion implantation parameters for photo modulated optical reflectance
Authors: Wang Xuesong , Zhang Lijun , Sun Yong , Min Jin , Wang Zhongyu , Liu Shiyuan , Chen Xiuguo , Tang Zirong
Published: August 2024

Photo modulated optical reflectance (PMOR) is an ideal ultra-shallow junction area metrology technique for measurement of transistor dopant distribution in integrated circuit fabrication, and the characterization of process parameters such as implant energy, implant angle, and implant dose has a significant impact on the accuracy of the ion implantation process. This study utilized deep learning to analyze various process parameters concurrently and assessed its performance on boron-doped silicon samples, the data were obtained from the power curves measured from Carrier Illumination (CI) experiments in PMOR, a deep learning model with multi-task learning architecture was developed and trained to characterize multiple process parameters, and the PMOR model incorporating a multi-task learning architecture for process parameters demonstrated superior performance in terms of accuracy and speed of characterization. The analyses indicated that applying deep learning methods to CI metrology in PMOR technology is feasible. In particular, compared with the conventional carrier irradiation technique, the ability to obtain the implantation dose and doping profile along with other process parameters such as implantation energy, implantation angle, and implantation type can better assist in the accurate realization of the ion implantation process with acceptable accuracy and time cost.
Atomic cluster expansion potential for large scale simulations of hydrocarbons under shock compression
Authors: Willman Jonathan T. , Perriot Romain , Ticknor Christopher
Published: August 2024

We present an Atomic Cluster Expansion (ACE) machine learned potential developed for high-fidelity atomistic simulations of hydrocarbons, targeting pressures and temperatures near and above supercritical fluid regimes for molecular fluids. A diverse set of stoichiometries were covered in training, including 1:0 (pure carbon), 1:4 (methane), and 1:1 (benzene), and rich bonding environments sampled at supercritical temperatures, hydrogen rich, reactive mixtures where metastable stoichiometries arise, including 1:2 (ethylene) and 1:3 (ethane). A high-fidelity training database was constructed by performing large-scale quantum molecular dynamic simulations [density functional theory (DFT) MD] of diamond, graphite, methane, and benzene. A novel approach to selecting structures from DFT MD is also presented, which allows for the rapid selection of unique DFT MD frames from complex trajectories. Comparisons to DFT and experimental data demonstrate that the presented ACE potential accurately reproduces isotherms, carbon melting curves, radial distribution functions, and shock Hugoniots for carbon and hydrocarbon systems for pressures up to 100 GPa and temperatures up to 6000 K for hydrocarbon systems and up to 9000 K for pure carbon systems. This work delivers a potential that can be used for accurate, large-scale simulations of shocked hydrocarbons and demonstrates a methodology for fitting and validating machine learning interatomic potentials to complex molecular environments, which can be applied to energetic materials in future works.
Tunable quasi-discrete spectrum of spin waves excited by periodic laser patterns
Authors: Filatov Ia. A. , Gerevenkov P. I. , Khokhlov N. E. , Kalashnikova A. M.
Published: August 2024

We present a concept for selective excitation of magnetostatic surface waves with a quasi-discrete spectrum using spatially patterned femtosecond laser pulses inducing either an ultrafast change of magnetic anisotropy or an inverse Faraday effect. We micromagnetically simulate the excitation of the waves with a periodically patterned uni- or bipolar laser impact. Such excitation yields multiple wavepackets propagating with different group velocities, whose dispersion corresponds to the set of quasi-discrete points. In addition, we show that the frequency of the spectral peaks can be controlled by the polarity of the periodic impact and its spatial period. The presented consideration of multiple spatially periodic magnetostatic surface wave sources as a whole enables implementation of a comprehensive toolkit of spatiotemporal optical methods for tunable excitation and control of spin-wave parameters.
Close-space sublimation of single-crystal metal films
Authors: Burton Oliver J. , Hofmann Stephan
Published: August 2024

Cost-effective, versatile, and rapid deposition of single-crystal metal films is crucial to a wide spectrum of applications ranging from catalysis, plasmonics, electrochemistry, and optoelectronics to templating, epitaxial substrates, and integrated nanomanufacturing. High crystal quality typically implies low growth rates, which makes it challenging to achieve thicknesses in excess of 1 µm with conventional approaches. We show facile close-space sublimation of epitaxial single-crystal Au, Ag, and Cu films on MgO substrates. We demonstrate 10 μm thickness in less than 1 h while maintaining sub-5 nm rms surface roughness for a range of low- and high-index crystal film orientations. We show that the results can be captured by a simple model based on “line-of-sight” sublimation, which serves as a predictive tool and provides a basis to discuss broader potential as well as the limitations of this approach.
Programmable transmission metasurface scattering control under obstacles based on deep learning
Authors: Wang Kai , Zhao Jiwei , Yang Zhangyou , Zhu Peixuan , Lu Huan , Zheng Bin
Published: August 2024

The emergence of 5G represents a pivotal step in merging mobile communication networks with the Industrial Internet of Things. Despite the numerous advantages of 5G, the presence of unknown obstacles can adversely affect user signals. Although mitigating signal pressures can be achieved by increasing base station density, it often involves bulky equipment and high costs. To address this, we propose a deep learning-based method for controlling tunable transmissive metasurfaces and validate their scattering control capabilities in the presence of obstacles. By constructing a network model to analyze the mapping relationship between metasurface arrays and far-field scattering, rapid control of scattering characteristics is achieved. AI-driven high-performance tunable metasurfaces exhibit vast potential applications in intelligent communication, offering a universal solution for intelligent control in complex signal environments.
Temporal scaling theory for bursty time series with clusters of arbitrarily many events
Authors: Jo Hang-Hyun , Birhanu Tibebe , Masuda Naoki
Published: August 2024

Long-term temporal correlations in time series in a form of an event sequence have been characterized using an autocorrelation function that often shows a power-law decaying behavior. Such scaling behavior has been mainly accounted for by the heavy-tailed distribution of interevent times, i.e., the time interval between two consecutive events. Yet, little is known about how correlations between consecutive interevent times systematically affect the decaying behavior of the autocorrelation function. Empirical distributions of the burst size, which is the number of events in a cluster of events occurring in a short time window, often show heavy tails, implying that arbitrarily many consecutive interevent times may be correlated with each other. In the present study, we propose a model for generating a time series with arbitrary functional forms of interevent time and burst size distributions. Then, we analytically derive the autocorrelation function for the model time series. In particular, by assuming that the interevent time and burst size are power-law distributed, we derive scaling relations between power-law exponents of the autocorrelation function decay, interevent time distribution, and burst size distribution. These analytical results are confirmed by numerical simulations. Our approach helps to rigorously and analytically understand the effects of correlations between arbitrarily many consecutive interevent times on the decaying behavior of the autocorrelation function.
Inactivation of microorganisms in model tissues by plasma-activated gas
Authors: Ma Sihong , Zhao Pengyu , Zhang Rui , Li Kaiyu , Song Tianyi , Zhang Zizhu , Wang Luge , Guo Li , Wang Zifeng , Zhang Hao , Liu Dingxin , Wang Xiaohua , Rong Mingzhe
Published: August 2024

Plasma is highly efficient in the inactivation of microorganisms and is tried to be applied to the treatment of wounds. The gas activated by plasma, named plasma-activated gas, can also effectively inactivate microorganisms and get rid of the limitations of direct plasma treatment. However, the details of the interaction of plasma-activated gas on the tissue are still unclear. In this study, the agarose gel models in the presence of microorganisms to simulate the infected tissues were used to study the inactivation effects and mechanisms of plasma-activated gas. The inactivation depths in the gel models in the presence of microorganisms were related to the types of plasma-activated gas and the species of microorganisms. The Mixed-gas exhibited the strongest inactivation effects, and the inactivation depths in the gel models in the presence of bacteria were deeper than those in the presence of fungi. The long-lived species in the plasma-activated gas penetrated to more than 5.2 mm while the short-lived species only penetrated less than 2.3 mm, demonstrating the distinct roles of reactive species in the inactivation process. Moreover, the pig muscle was covered on the gel models to assess the penetration depths of the plasma-activated gas in muscle tissue and the focused plasma-activated gas could penetrate 1–1.5 mm of pig muscle. This study explored the inactivation effects and mechanisms on the gel models and the penetration depths in the real tissues of plasma-activated gas, which supplied the theoretical basis for the further application of plasma-activated gas in biomedical fields.
Role of Atwood number in the shock-induced evolution of a double-layer gas cylinder
Authors: Li Xin , Hao Jiaao , Wen Chih-Yung , Fan E.
Published: August 2024

An A/B/C-type gas cylinder with various concentrations of SF6 (ranging from 5% to 80% in volume fraction) in the inner cylinder is constructed to investigate the dependence of the interface evolution on the Atwood number. For negative Atwood numbers, secondary vortex pairs emerge at the downstream interface of the outer cylinder following the interaction of a high-pressure triple point with the downstream interface, while a downstream jet is formed due to the generation of a notably higher-pressure zone after the transmitted shock wave traverses the convergence point. The widths and heights of both outer and inner cylinders are analyzed to quantify the interface evolution. The mechanism behind the vorticity evolution is investigated using the vorticity transport equation. The vorticity equation is introduced to investigate the mechanism of vorticity evolution. The dilatation and baroclinic terms play a dominant role in the dynamics of vorticity production. The net circulation can be predicted by linearly summing existing circulation models. Analysis of the area and mean mass fraction histories of the outer and inner cylinders shows that more ambient gas dilutes SF6 and promotes gas mixing as the Atwood number decreases.
Analyzing the dynamic behavior of the Gierer–Meinhardt model using finite difference method
Authors: Lv Jianping , Jing Hefang
Published: August 2024

In this paper, a numerical computation method for the Gierer–Meinhardt model in two-dimensional space diffusion with homogeneous Neumann boundary conditions, considering the interaction between activator and inhibitor substances, is proposed. First, a high-order compact finite difference scheme is constructed for the Gierer–Meinhardt model using the finite difference method. A fourth-order compact difference scheme is applied to the second-order spatial derivative terms, while the time derivative terms are discretized using Taylor series expansion and residual correction functions. Consequently, the difference scheme achieves fourth-order accuracy in space and second-order accuracy in time for the Gierer–Meinhardt model. In addition, the stability of the difference scheme is demonstrated using Fourier analysis. Finally, numerical simulations are conducted on the Gierer–Meinhardt model near its equilibrium point to explore the impact of the inhibitor degradation rate, denoted as E, on the pattern formation. The model exhibits distinct pattern structures with varying E, thereby revealing the relationship between tissue variability and pattern formation in biological systems.
PyCTRAMER: A Python package for charge transfer rate constant of condensed-phase systems from Marcus theory to Fermi’s golden rule
Authors: Liu Zengkui , Brian Dominikus , Sun Xiang
Published: August 2024

In this work, we introduce PyCTRAMER, a comprehensive Python package designed for calculating charge transfer (CT) rate constants in disordered condensed-phase systems at finite temperatures, such as organic photovoltaic (OPV) materials. PyCTRAMER is a restructured and enriched version of the CTRAMER (Charge-Transfer RAtes from Molecular dynamics, Electronic structure, and Rate theory) package [Tinnin et al. J. Chem. Phys. 154, 214108 (2021)], enabling the computation of the Marcus CT rate constant and the six levels of the linearized semiclassical approximations of Fermi’s golden rule (FGR) rate constant. It supports various types of intramolecular and intermolecular CT transitions from the excitonic states to CT state. Integrating quantum chemistry calculations, all-atom molecular dynamics (MD) simulations, spin-boson model construction, and rate constant calculations, PyCTRAMER offers an automatic workflow for handling photoinduced CT processes in explicit solvent environments and interfacial CT in amorphous donor/acceptor blends. The package also provides versatile tools for individual workflow steps, including electronic state analysis, state-specific force field construction, MD simulations, and spin-boson model construction from energy trajectories. We demonstrate the software’s capabilities through two examples, highlighting both intramolecular and intermolecular CT processes in prototypical OPV systems.
Theory and quantum dynamics simulations of exciton-polariton motional narrowing
Authors: Ying Wenxiang , Mondal M. Elious , Huo Pengfei
Published: August 2024

The motional narrowing effect has been extensively studied for cavity exciton–polariton systems in recent decades both experimentally and theoretically, which is featured by (1) the subaverage behavior and (2) the asymmetric linewidths for the upper polariton and the lower polariton. However, a minimal theoretical model that is clear and adequate to address all these effects as well as the linewidth scaling relations remains missing. In this work, based on the single mode 1D Holstein–Tavis–Cummings (HTC) model, we studied the motional narrowing effect of the polariton linear absorption spectra via both semi-analytic derivations and numerically exact quantum dynamics simulations using the hierarchical equations of motion approach. The results reveal that under collective light–matter coupling between a cavity mode and N molecules, the polariton linewidth scales as 1/N under the slow limit, while scales as 1/N under the fast limit, due to the polaron decoupling effect. Furthermore, by varying the detunings, the polariton linewidths exhibit significant motional narrowing, covering both characters mentioned above. Our analytic linewidth expressions [Eqs. (34) and (35)] agree well with the numerical exact simulations in all the parameter regimes we explored. These results indicate that the physics of motional narrowing is adequately accounted for by the single-mode 1D HTC model. We envision that both the numerical results and the analytic polariton linewidths expression presented in this work will offer great theoretical value for providing a better understanding of the exciton–polariton motional narrowing based on the HTC model.
Substance Use in Forensic Assertive Community Treatment: Development and Implementation of a Pilot Project for Internees in Belgium
Authors: Marquant Thomas , Van Nuffel Meike , Sabbe Bernard , Goethals Kris
Published: August 2024

Substance use is a significant factor associated with new arrests, detentions and compulsory admissions for patients in forensic assertive community teams (FACT). To enhance community tenure for forensic patients and facilitate their sustainable integration into society, a treatment that offers a community-based alternative to admission following substance use was developed. In this paper, the development of the project, FENIX + is described along with the reporting of a pilot study of all included patients during 12 months ( N = 24). Recidivism risk and community integration were assessed utilizing the Short-Term Risk Assessment and Treatability (START) as well as the Measurements in Addiction for Triage and Evaluation (MATE) scales. The included patients avoided 60% of admissions, exhibited positive changes in their desire for assistance, and successfully reduced their risk of recidivism. By accessing the community-based alternative, they were able to delay admissions effectively. These promising results suggest that a community-based treatment could benefit patients at risk of reoffending following substance use.
An on-chip photonic digital-to-analog converter with phase-change-based bit control
Authors: Li Jingxi , Sun Jigeng , Ye Ziyang , Fan Zhihua , Zhou Shaolin
Published: August 2024

In this paper, we propose an N-bit optical digital-to-analog converter (DAC) by integrating N pairs of

2
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2

phase change based on-chip photonic switches and

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multimode interference (MMI) splitters. An on-chip photonic switch is constructed by integrating a wavelength-selectable racetrack micro-ring resonator with the phase change chalcogenide Ge2Sb2Se4Te (GSST). The GSST-integrated switch utilizes a racetrack resonator configuration for performing the accurate modulation of the resonant wavelength to prevent intercoupling between adjacent units. In order for electrothermal heating of the GSST film to trigger its phase transition for switchable control, an indium tin oxide heater with a bowtie-shaped structure is integrated into the racetrack resonator. Using numerical calculations, we demonstrate that an 8 V voltage pulse at a duration of 300 ns, with an energy consumption of 18.45 nJ, could change the optical state from an OFF state to an ON state. Another 6 V voltage pulse of 250 ns duration, followed by a 4 V pulse of varying duration, with a total energy consumption of 34.78 nJ, can switch the optical state from an ON state to an OFF state. The asymmetric structure of the

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MMI shows ultra-high transmittance approaching 50% in the through port (connected to the next order of MMI), enabling the creation of multistage cascaded MMI splitters with an output light power ratio close to 50%. Our results show that this configuration potentially offers a feasible solution for applications of optical DACs.
Evaluation of radiation protection effectivity in a cardiac angiography room using visualized scattered radiation distribution
Authors: Fujibuchi Toshioh , Nakashima Misaki , Arakawa Hiroyuki , Miyazaki Hitoshi , Anam Choirul
Published: August 2024

In this study, we devised a radiation protection tool specifically designed for healthcare professionals and students engaged in cardiac catheterization to easily monitor and evaluate scattered radiation distribution across diverse C-arm angles and arbitrary physician associated staff positions—scrub nurse and technologist positions. In this study, scattered radiation distributions in an angiography room were calculated using the Monte Carlo simulation of particle and heavy ion transport code system (PHITS) code. Four visualizations were performed under different C-arm angles with and without radiation protection: (1) a dose profile, (2) a 2D cross-section, (3) a 3D scattered radiation distribution, and (4) a 4D scattered radiation distribution. The simulation results detailing the scattered radiation distribution in PHITS were exported in Visualization Toolkit format and visualized through the open-source visualization application ParaView for analysis. Visualization of the scattered dose showed that dose distribution depends on the C-arm angle and the x-ray machine output parameters (kV, mAs s−1, beam filtration) which depend upon beam angulation to the patient body. When irradiating in the posterior–anterior direction, the protective curtain decreased the dose by 62% at a point 80 cm from the floor, where the physician’s gonads are positioned. Placing the protection board close to the x-ray tube reduced the dose by 24% at a location 160 cm from the floor, where the lens of the eye is situated. Notably, positioning the protection board adjacent to the physician resulted in a 95.4% reduction in incident air kerma. These visualization displays can be combined to understand the spread and direction of the scattered radiation distribution and to determine where and how to operate and place radiation protection devices, accounting for the different beam angulations encountered in interventional cases. This study showed that scatter visualization could be a radiation protection teaching aid for students and medical staff in angiography rooms.
Effects of organ dose modulation applied to a part of the scan range on radiation dose in computed tomography of the body
Authors: Inoue Yusuke , Itoh Hiroyasu , Koizumi Koji , Sekimoto Saori , Hata Hirofumi , Miyatake Hiroki , Yamane Takuro , Mitsui Kohei
Published: August 2024

In computed tomography (CT), organ dose modulation (ODM) reduces radiation exposure from the anterior side to reduce radiation dose received by the radiosensitive organs located anteriorly. We investigated the effects of ODM applied to a part of the scan range on radiation dose in body CT. The thorax and thoraco-abdominopelvic region of an anthropomorphic whole-body phantom were imaged with and without ODM. ODM was applied to various regions, and the tube current modulation curves were compared. Additionally, the dose indices were compared with and without ODM in thoracic and thoraco-abdominopelvic CTs in 800 patients. ODM was applied to the thyroid in male patients and to the thyroid and breast in female patients. In phantom imaging of the thorax, the application of ODM below the scan range decreased the tube current, and that to the breast showed a further decrease. Decreased tube current was also observed in phantom imaging of the thoraco-abdominopelvic regions with ODM below the scan range, and the application of ODM to the whole scan range, thyroid, breast, and both thyroid and breast further reduced the tube current in the region to which ODM was applied. In patient imaging, the dose indices were significantly lower with ODM than without ODM, regardless of the scan range or sex. The absolute reduction in dose-length product was larger for thoraco-abdominopelvic CT (male, 43.2 mGy cm; female, 59.7 mGy cm) than for thoracic CT (male, 30.8 mGy cm; female, 37.6 mGy cm) in both sexes, indicating dose reduction in the abdominopelvic region to which ODM was not applied. In conclusion, The application of ODM in body CT reduces radiation dose not only in the region to which ODM is applied but also outside the region. In radiation dose management, it should be considered that even ODM applied to a limited region affects the dose indices.
Controlled electrodeposition of cobalt nanowires using iR compensation and their electron transport properties
Authors: Sotnichuk Stepan V , Skryabina Olga V , Shishkin Andrey G , Golovchanskiy Igor A , Bakurskiy Sergey V , Stolyarov Vasily S , Napolskii Kirill S
Published: August 2024

Superconducting hybrid structures based on single nanowires are a new type of nanoscale devices with peculiar transport characteristics. Control over the nanowire structure is essential for understanding hybrid electronic phenomena arising in such complex systems. In this work, we report a technique for the fabrication of cobalt nanowires by template-assisted electrodeposition using iR compensation, which allows revealing the fundamental dependence of the preferred direction of nanowire growth on the deposition potential. Long coarse-grained cobalt nanowires with a diameter of 70 nm have been implemented into Nb/Co/Nb hybrid structures. We demonstrate that using electrode fabrication techniques that do not contaminate the surface of the nanowire leads to a high quality of devices with low-resistance interfaces. Low-temperature resistivity of 4.94 ± 0.83 µΩ cm and other transport characteristics of Co nanowires are reported. The absence of long-range superconducting proximity effect for Nb/Co/Nb systems with different nanowire length is discussed.
Airborne car on a hill
Authors: Cross Rod
Published: August 2024

A car rising up a hill can become airborne if it is travelling fast enough. Trajectories are calculated for several curved hills to illustrate the physics involved.
Phase formation and kinetic analysis of (Ba, K)Fe2As2 superconductor
Authors: Liu Xinyuan , Zhang Xianping , Dong Chiheng , Tang Minghui , Yao Chao , Li Wenchao , Wang Dongliang , Ma Yanwei
Published: August 2024

122-type iron-based superconductors have attracted significant attention owing to their potential for high-field applications. Therefore, the study of the reaction mechanism is indispensable. In this work, the phase formation process and reaction kinetics of the Ba–K–Fe–As system were investigated in comparison with the Fe–As and Ba–Fe–As systems. Our findings suggest two main stages of the phase formation process: formation of the iron arsenide phase and its transformation to the 122-phase. It shows that FeAs forms slowly below 300 °C in the Ba–K–Fe–As system, and the formation significantly accelerates at ∼400 °C. KFe2As2 starts to generate at ∼640 °C and gradually transforms into Ba0.6K0.4Fe2As2. Furthermore, using the Flynn–Wall–Ozawa method and the Kissinger method, the kinetic parameters of the exothermic peak at ∼400 °C–580 °C for these three systems were obtained, including the most probable mechanism function f(α), apparent activation energy E, and apparent pre-exponential factor A. Our results suggest that all three systems exhibit complex reactions characterized by f(α) = (1 − α)
n
(1 < n < 2). The presence of the kinetic compensation effect in the three systems was discovered, implying similarities in their respective reaction mechanisms. Additionally, influence mechanism of K doping on the apparent activation energy and reaction rate was analyzed.
A fully superconducting magnetic bearing with a jointless coil excited by a superconducting dynamo
Authors: Espenhahn Tilo , Hühne Ruben
Published: August 2024

Superconducting magnetic bearings usually combine a setup of permanent magnets (PMs) and superconducting bulks. The bearing size is typically scaled up to increase the levitation force as the force density is limited in such setups due to the magnetic flux density and its spatial gradient. As alternative, the PMs might be replaced by a superconducting coil. To test this, jointless coils were prepared by a wind and flip technology using coated conductors of different tape manufacturers. The realized pancake coils were studied at liquid nitrogen temperature. Numerical simulations yielded a magnetic field of up to 0.5 T at 77 K for coils with a inner diameter of 20 mm. The prepared coils were charged with a superconducting dynamo, in which two magnet configurations were tested. A clear dependence on the magnet size and frequency was found for the charging characteristics. A magnetic field of about 0.3 T at 77 K was imprinted in one of the coils. However, a degradation of the coils was found over time indicated by some delamination at the cutted edges, which reduced the maximum achievable magnetic field after a few weeks. Nevertheless, a fully superconducting bearing was realized with by combining the jointless coil with an additional YBCO bulk. After charging the coil with the dynamo, a levitation force of up to 10 N at 77 K was measured under zero-field cooling conditions. The generated levitation force decayed only slightly after charging indicating low losses in the coil.
Reducing the number of qubits in quantum simulations of one dimensional many-body Hamiltonians
Authors: Mehrabankar Somayeh , Ángel García-March Miguel , Almudéver Carmen G , Pérez Armando
Published: August 2024

We investigate the Ising and Heisenberg models using the block renormalization group method (BRGM), focusing on its behavior across different system sizes. The BRGM reduces the number of spins by a factor of 1/2 (1/3) for the Ising (Heisenberg) model, effectively preserving essential physical features of the model while using only a fraction of the spins. Through a comparative analysis, we demonstrate that as the system size increases, there is an exponential convergence between results obtained from the original and renormalized Ising Hamiltonians, provided the coupling constants are redefined accordingly. Remarkably, for a spin chain with 24 spins, all physical features, including magnetization, correlation function, and entanglement entropy, exhibit an exact correspondence with the results from the original Hamiltonian. The study of the Heisenberg model also shows this tendency, although complete convergence may appear for a size much larger than 24 spins, and is therefore beyond our computational capabilities. The success of BRGM in accurately characterizing the Ising model, even with a relatively small number of spins, underscores its robustness and utility in studying complex physical systems, and facilitates its simulation on current NISQ computers, where the available number of qubits is largely constrained.
Position dependent mass dissipative scalar field at finite temperature
Authors: Jafari Marjan
Published: August 2024

Position dependent mass dissipative scalar field is a theoretical framework that combines the concepts of position-dependent mass and dissipative systems in the context of scalar field theory. In this framework, the mass of the scalar field is allowed to vary with position, leading to interesting physical phenomena such as non-locality and non-Hermiticity. We consider a generalized classical Lagrangian for the system and by developing a theoretical formulation, quantized system canonically. In follow, two-point correlation functions of the system is obtained at finite temperature and Free energy of the system is calculated in terms of Matsubara frequencies. This research can provide insights into the behavior of particles and fields in non-uniform environments, and has potential applications in various fields of physics.