bluuebunny/crossref_metadata_2025 huggingface dataset:
Invasive Neurostimulation in der Neuro-Urologie: State of the Art
Authors: Kurze Ines , Böthig Ralf , van Ophoven Arndt
Published: April 2024

Die Modulation oder Stimulation der den unteren Harntrakt versorgenden Nerven stellt bei Versagen der konservativen oder minimalinvasiven Behandlungsansätze eine mögliche Therapieoption bei Dysfunktion des unteren Harntrakts, des Beckenbodens und des Mastdarms dar. Diese Übersicht zeigt die Möglichkeiten und Grenzen der sakralen Neuromodulation, der sakralen Deafferentation mit sakraler Vorderwurzelstimulation sowie der Konus-Deafferentation auf.

Die sakrale Neuromodulation (SNM) ist ein Verfahren zur Behandlung von refraktären Beckenbodenfunktionsstörungen verschiedenster Genese (idiopathisch, neurogen oder postoperativ), wie überaktive Blase, nicht obstruktive Retention und Stuhlinkontinenz. Besonderer Vorteil der SNM ist die Möglichkeit einer vorherigen Teststimulation mit einer hohen prognostischen Aussagekraft. Das Verfahren ist minimalinvasiv, reversibel und mit relativ niedrigen Morbiditätsraten verbunden.

Nach der Einführung von MRT-kompatiblen SNM-Systemen wurde das Interesse an der Behandlung von neurogenen Blasenfunktionsstörungen neu entfacht. Eine neuere Metaanalyse berichtet dabei über ähnliche Erfolgsraten, wie bei der idiopathischen Patientenpopulation.

Die sakrale Deafferentation mit Implantation eines sakralen Vorderwurzelstimulators (SARS/SDAF) stellt eine exzellente therapeutische Option für Patienten mit Querschnittlähmung dar, welche einerseits die Lebensqualität der Betroffenen erheblich verbessert und andererseits neben der Behandlung der neurogenen Dysfunktion des unteren Harntrakts auch die neurogene Darmfunktionsstörung, die neurogene Sexualfunktionsstörung oder eine autonome Dysreflexie positiv beeinflussen kann. Entscheidend für den Erfolg dieser Operation ist es, bei Versagen der konservativen bzw. minimalinvasiven Therapie frühzeitig die SDAF/SARS in Erwägung zu ziehen, um irreversible organische Schäden zu vermeiden.

Die Konus-Deafferentation (KDAF) stellt eine weniger invasive operative
Behandlungsmöglichkeit für Querschnittgelähmte dar, bei denen eine sakrale Deafferentation
indiziert wäre, welche jedoch von der gleichzeitigen Implantation eines sakralen
Vorderwurzelstimulators nicht profitieren würden. Grundsätzlich bleibt auch diesen Patienten
später die Möglichkeit, mit einem extraduralen Implantat versorgt zu werden und damit die
Vorteile der Vorderwurzelstimulation zu nutzen. Indikationen für eine KDAF sind die autonome
Dysreflexie, die therapierefraktäre Detrusorüberaktivität, rezidivierende Harnwegsinfekte,
Harninkontinenz und die durch die Detrusorüberaktivität getriggerte Spastik. Mit der KDAF
verfügen wir über ein sicheres und effizientes Verfahren mit einem hohen Potenzial für die
Verbesserung des paraplegiologischen und neuro-urologischen Therapiespektrums.
Essverhalten und Muskeldysmorphie in der Adoleszenz
Authors: Pahr-Hosbach Sandra
Published: April 2024

Muskeldysmorphie (MD) ist eine Störung mit ausgeprägter Dissonanz hinsichtlich
der Quantität und Qualität der äußerlich erkennbaren Muskulatur. Bedingt durch
ein rigides und zeitintensives Trainingsregime sowie restriktive
Ernährungspraktiken beeinträchtigt sie stark die Rollenfunktionen. Männliche
Jugendliche sind aufgrund hormoneller Einflüsse, intensiver Umbauprozesse im
Gehirn und sozialer Herausforderungen besonders vulnerabel.
Antiphospholipid-Syndrom: neue Klassifikationskriterien und
Implikationen für die Praxis
Authors: Stefanski Ana-Luisa , Dörner Thomas
Published: April 2024

Analog zu anderen entzündlich-rheumatischen Erkrankungen wurden im Oktober 2023
neue hierarchisch gruppierte, gewichtete und risikostratifizierte APS
Klassifikationskriterien von der European League Against Rheumatism (EULAR)
gemeinsam mit dem American College of Rheumatology (ACR) vorgestellt. Die neuen
Kriterien sehen als obligates Eingangskriterium das Vorliegen mindestens einer
klinischen APS-Manifestation und eines positiven aPL-Labortests vor
(Lupusantikoagulans oder moderat bis deutlich erhöhte IgG- oder IgM-Titer für
aCL oder aß2GPI). Die sechs Klinik- und zwei Labordomänen werden mit Werten von
1–7 Punkten gewichtet. Eine Klassifikation als APS kann erfolgen, wenn
mindestens jeweils 3 Punkte in den klinischen und den serologischen Domänen
erreicht werden. Neu werden traditionelle Thromboserisikofaktoren bei
aPL-positiven Personen mitberücksichtigt und eine genauere Charakterisierung
aPL-assoziierter mikrovaskulärer, geburtshilflicher und nichtthrombotischer
Manifestationen (Thrombozytopenie und Herzklappenbeteiligung) vorgenommen.
IgM-aPL zählen als weniger spezifisch und werden mit einer deutlich geringeren
Punktezahl (1 Punkt) gegenüber den IgG-aPL (je nach Höhe und Konstellation 4-7
Punkte) berücksichtigt. Die erreichte hohe Spezifität der neuen
Klassifikationskriterien wird qualitativ hochwertige Studien im APS mit dem Ziel
einer verbesserten Patientenversorgung erlauben. Der Beitrag fokussiert auf
aktuelle Herausforderungen durch die Klassifikationskriterien sowie die
unabhängig zu sehenden Aspekte der klinischen Diagnosestellung und der daraus
erwachsenen Behandlungskonsequenzen.
Pneumoperikard bei einem reifen Neugeborenen
Authors: Piepenbrink Lea , Herrmann Jochen , Jahn Matthias , Klinkenberg Dennis , Diehl Thilo , Singer Dominique , Lange Mario
Published: April 2024

Fallpräsentation

Reifes weibliches Neugeborenes (40+1 SSW), das nach unauffälliger Schwangerschaft per
sekundärer Sectio bei pathologischem CTG in einer Geburtsklinik geboren wurde.
Geburtsgewicht 3500 g, Nabelarterien-pH 7,28, Apgar 7/8/8. Wegen respiratorischer
Adaptationsstörung mit Tachydyspnoe und O2-Bedarf wurde der
Neugeborenennotarzt alarmiert. Bis zum Eintreffen supportive Therapie mittels
CPAP-Atemhilfe (PEEP 6 mbar) sowie Beginn einer antibiotischen Therapie mit
Ampicillin und Tobramycin. Im Verlauf weitere klinische Verschlechterung mit
gemischter Azidose in der kapillären Blutgasanalyse (pH 6,93, pCO2 82
mmHg, BE − 14,9 mmol/l, Laktat 10,5 mmol/l). Zunehmende Kreislaufinstabilität mit
verlängerter Kapillarfüllungszeit, Tachykardie (180/min) und arterieller Hypotension
(MAD 33 mmHg) bei nur leise auskultierbaren Herztönen. Nach Eintreffen des
Neugeborenennotarztes endotracheale Intubation und maschinelle Beatmung. Zudem
Kreislaufstabilisierung mit Volumen und Dobutamin und zügiger Transport auf die
neonatologische Intensivstation des Perinatalzentrums.
Geschlechtsspezifische Unterschiede von Motorik und Balance bei
Gonarthrosepatienten
Authors: Anders Jens Olaf , Redelbach Robert , Könczöl Clemens
Published: April 2024

Hintergrund Trotz vielfältiger perioperativer Verbesserungen sind bis
heute noch 10 bis 20 Prozent der Patienten nach Knietotalendoprothesen
Operationen unzufrieden. Individuelle und insbesondere auch
geschlechtsspezifische Defizite motorischer und propriozeptive Fähigkeiten
könnten dabei eine wichtige Rolle spielen. Bisher wird dieser Tatsache wenig
Aufmerksamkeit gewidmet und vor Endoprothesen Operationen routinemäßig keine
Messungen durchgeführt.

Methoden Bei jeweils 30 weiblichen und männlichen Patienten erfolgte einen
Tag vor Implantation einer bikondylären Knietotalendoprothese mittels mobiler
Kraftmessplatte KMP die Messung von Kraft/Leistung und Balance. Die Kraft der
Beinmuskulatur konnte durch modifiziertes Kreuzheben bestimmt und die Leistung
mit 5 schnellen Kniebeugen gemessen werden. Die Balance umfasste die Parameter
Schwankungsweg (in mm) und Schwankungsfläche (in mm²). Freies Stehen im
Einbeinstand bzw. mit Hilfestellung wurden durch kurzes Antippender Finger an
seitlich angebrachten Stützen bzw. permanentes Festhalten zusätzlich als
Balanceunterstützung erfasst.

Ergebnisse Die Mittelwerte der Gesamtperformance Kraft/Leistung waren bei
Männer mit 0.44 (SD 0.96, Min –1.15, Max 2.43) statistisch gesichert
(p<0.0001) höher als bei Frauen –0.41 (SD 0.61, Min –1,34, Max 1,32). In der
Gesamtperformance Balance aus Schwankungsweg und -fläche zeigten sich
statistisch signifikant bessere Ergebnissen bei Frauen (p = 0.013). Der
Mittelwert betrug für Frauen –0.24 (SD 0.72, Min –1,72, Max 1,22) und bei Männer
0.27 (SD 0.89, Min –1.56, Max 3,21).

Schlussfolgerung Bei weiblichen und männlichen Gonarthrosepatienten waren
präoperativ mit alltagstauglichem Aufwand motorische/propriozeptive
Eigenschaften messbar. Es konnte gezeigt werden, dass statistisch gesicherte
Leistungsunterschiede zwischen Frauen und Männern mit Gonarthrose Gard 4
vorhanden sind. Diese Defizite können zukünftig sowohl prä- als auch
postoperativgezielter bestimmt werden. Inwieweit sich die Fähigkeiten mit
individualisierten Rehabilitationsmaßnahmen verbessern lassen, muss in
Folgestudien untersucht werden.
Cardioprotective Effects of Aloysia polystachya Essential Oil on a Rat Model with Multiple Cardiovascular Risk Factors
Authors: Moreno Karyne Garcia Tafarelo , Marques Aline Aparecida Macedo , da Silva Gabriela Pereira , Bertoncelo Luana Ale , Pessoal Luciane Barbosa , Gonçalves Larissa Dantas , dos Santos Ariany Carvalho , Souza Roosevelt Isaías Carvalho , Silva Denise Brentan , Gasparotto Junior Arquimedes
Published: April 2024

Traditional medicine is a frequently utilized method to treat cardiovascular disease and its primary risk factors, including hypertension and dyslipidemia. Aloysia polystachya is a species that is commonly employed to treat various pathological conditions, and it has already been identified as having some cardioprotective effects. This study aimed to investigate the protective effects of the essential oil extracted from the leaves of A. polystachya in a rat model that simulates multiple cardiovascular risk factors. We evaluate the acute toxicity, as well as the cardioprotective effects, by giving different doses of A. polystachya essential oil (1.47 mg/kg, 4.40 mg/kg, and 13.20 mg/kg) over a period of 42 days. The control group was treated with rosuvastatin (5 mg/kg). At the end of the treatments, the renal function, electrocardiography, blood pressure, vascular reactivity, serum biochemical profile, and organ histopathology were evaluated. The main compounds identified in
the essential oil of A. polystachya using gas chromatography coupled with mass spectrometry were beta-myrcene (1.08%), limonene (40.13%), and carvone (56.47%). The essential oil of A. polystachya not only lacks acute toxicity but also mitigates the reduction in the excretion of sodium, chloride, and creatinine in urine. Furthermore, it reduces electrocardiographic abnormalities and decreases blood pressure levels. Moreover, this treatment prevents an elevation in markers of inflammation and oxidative stress in the bloodstream. Our findings indicate significant cardioprotective effects of the essential oil of A. polystachya against multiple risk factors for cardiovascular diseases in hypertensive rats.
From Protein Structures to Functional Biomimetics
Authors: Grossmann Tom N. , Durukan Canan
Published: April 2024

The development of complex molecular scaffolds with defined folding properties represents a central challenge in chemical research. Proteins are natural scaffolds defined by a hierarchy of structural complexity and have evolved to manifest unique functional characteristics; for example, molecular recognition capabilities that facilitate the binding of target molecules with high affinity and selectivity. Utilizing these features, proteins have been used as a starting point for the design of synthetic foldamers and enhanced biocatalysts, as well as bioactive reagents in drug discovery. In this account, we describe the strategies used in our group to stabilize protein folds, ranging from the constraint of bioactive peptide conformations to chemical protein engineering. We discuss the evolution of peptides into peptidomimetics to inhibit protein–protein and protein–nucleic acid interactions, and the selective chemical modification of proteins to enhance their properties for biotechnological applications. The reported peptide- and proteomimetic structures cover a broad range of molecular sizes and they highlight the importance of structure stabilization for the design of functional biomimetics.

1 Introduction

2 Constraining the Conformation of Peptides

3 Peptide-Based Covalent Protein Modifiers

4 Chemical Protein Engineering

5 Conclusions
Defining an Evaluation Protocol for the Infant with Fetal Echogenic Bowel
Authors: Alsup Kendall , Pearson Jessica L. , Bowe Andrew , Woodham Padmashree C.
Published: April 2024

Objective This study aimed to develop an algorithm for pediatricians to use for infants diagnosed with fetal echogenic bowel (FEB) to ensure that each patient is fully evaluated for possible complications while avoiding unnecessary morbidity and mortality and health care-associated costs.

Study Design This was a prospective cohort of neonates for which a diagnosis of FEB was made during a Level 2 anatomy ultrasound between February 2016 and January 2017. Women diagnosed with FEB were offered perinatal genetic counseling and testing. These women also received increased third trimester fetal surveillance, including daily fetal kick counts, fetal growth scans every 3 to 4 weeks beginning at 28 weeks, and weekly fetal nonstress test (NST) and/or BPP beginning at 32 weeks. After delivery, neonates received a postnatal evaluation including birth weight, gestational age at birth, presence of other abnormalities, and associated perinatal morbidity and mortality. Comparison between findings was performed using chi-square test. All statistical evaluation was performed using SPSS.

Results Among 919 pregnant patients who received Level 2 anatomy ultrasounds at a Regional Perinatal Center during the study period, 70 received a diagnosis of FEB. Of those diagnosed with FEB, 52 (74.3%) delivered at the same Regional Medical Center. Of these 52 delivered infants, 3 (5.8%) were intrauterine fetal demises (IUFDs) and 4 (7.6%) had unaffected twins. Only one multifetal gestation had the diagnosis of FEB in both the twins. Only 19 of the infants delivered had a kidney, ureter, and bladder X-ray (KUB) performed secondary to prematurity or abnormal exams.

Conclusion This study showed that the majority of infants diagnosed with FEB had a normal exam following delivery, and that most of the neonatal outcomes of neonatal intensive care unit admissions and other neonatal complications are a result of prematurity rather than FEB. Although the algorithm did not have significant results, it is easy to follow and implement in larger studies.

Key Points
Buccal versus Vaginal Misoprostol Combined with a Foley Catheter among Individuals with Obesity Undergoing Induction
Authors: Gomez Slagle Helen B. , Kawakita Tetsuya , Hoffman Matthew K. , Sciscione Anthony C. , Ma'ayeh Marwan
Published: April 2024

Objective Combining pharmacologic agents with mechanical ripening achieves the shortest labor duration, yet there is no clear evidence on route of drug administration in obese individuals. The use of buccal misoprostol has shown greater patient acceptance but remains understudied. Our objective was to evaluate the difference in time to delivery of buccal compared with vaginal misoprostol in combination with a Foley catheter (FC) for induction of labor (IOL) in the obese population.

Study Design This was a secondary analysis of a randomized controlled trial comparing identical dosages (25 μg) of buccal and vaginal misoprostol in combination with a FC. The parent trial was an institutional review board-approved, randomized clinical trial conducted from June 2019 through January 2020. Labor management was standardized among participants. Women undergoing IOL at ≥37 weeks with a singleton gestation and cervical dilation ≤2 cm were included. Body mass index (BMI, kg/m2) was stratified. The primary outcome was time to delivery.

Results A total of 215 participants were included. Demographic characteristics were similar between the three groups. Vaginal drug administration achieved a faster median time to delivery than the buccal route among patients with a body mass index greater than or equal to 30 kg/m2 (vaginal misoprostol–FC: 21.3 hours vs. buccal misoprostol–FC: 25.2 hours, p = 0.006). There was no difference in the cesarean delivery rate between the two groups. Furthermore, patients with a BMI greater than or equal to 30 kg/m2 receiving vaginal misoprostol delivered 1.2 times faster than women who received buccal misoprostol after censoring for cesarean delivery and adjusting for parity (hazard ratio: 1.2, 95% confidence interval: 1.1–1.7). There were no significant differences in maternal and neonatal outcomes.

Conclusion We found that vaginal misoprostol was superior to buccal misoprostol when combined with a FC among individuals with a BMI greater than or equal to 30 kg/m2. Vaginal misoprostol should be the preferred route of drug administration for term IOL in this population.

Key Points
Change in Femoral Cartilage Cross-Sectional Area After Aerobic and
Resistance Exercise
Authors: Lim Junhyeong , Lee Jaewook , Park Sanghyup , Lee Jinwoo , Kim Jaewon , Park Jihong
Published: April 2024

We compared the immediate response and recovery of femoral cartilage morphology
following aerobic or resistance exercise to a control condition. Fifteen healthy
young males (23.9 years; 170.1 cm; 69.7 kg) visited the laboratory three
separate days and randomly performed one of the 30-min exercise aerobic
exercises (treadmill running), resistance exercises (leg presses, back squats,
and knee extensions), or seated rest as the control, each followed by the 50-min
recovery. Ultrasonographic images of the femoral cartilage cross-sectional area
(CSA) were obtained before and after exercise and every 5 min thereafter. To
test exercise effects over time, a mixed model analysis of variance and
Tukey–Kramer post-hoc tests were performed (p<0.05). The femoral
cartilage CSA was different (condition×time: F34,742=4.30,
p<0.0001) and the femoral cartilage CSA was decreased after the
aerobic (−5.8%, p<0.0001) and the resistance (−3.4%, p=0.04)
exercises compared to the pre-exercise levels. Deformed femoral cartilage
CSA took 35 and 10 min to return to the pre-exercise levels after aerobic and
resistance exercises (p+>+0.09), respectively. Thirty minutes of
moderate exertion performing aerobic or resistance exercises immediately reduced
the femoral cartilage CSA. A rest period ranging from 10 to 35 min was required
for cartilage recovery after weight-bearing exercises.
Equitable Representation of Pregnant and Lactating Women in Clinical Research: A Historical Review and Critical Analysis of Proposed Legislation
Authors: Woods Richard H.
Published: April 2024

A long history of policymaking and regulation constructed for the purpose of ensuring adequate fetal and infant protections has inadvertently sanctioned the widespread exclusion of pregnant and lactating patients from biomedical research, leaving a paucity of high quality data necessary for clinical decision-making. Although well-intended, the regulatory classification of pregnant women as “vulnerable,” in conjunction with burdensome enrollment criteria and other factors weighing against broad inclusion, have ultimately placed the health and safety of these women and their babies in jeopardy. Robust measures are urgently needed to overcome patient and physician reluctance, address substantial evidence gaps, and rectify long-standing disparities which precipitate disproportionately poor health outcomes among this population. In February 2023, the Advancing Safe Medications for Moms and Babies Act of 2023 (the Act) was introduced in the United States House of Representatives with the overarching goal of enabling pregnant and lactating women to achieve equitable participation in clinical research and contribute to developing important biomedical knowledge to guide and improve health care delivered to these patients. This review discusses the historical influence of federal human subject protection regulations on the health and clinical treatment of pregnant and lactating women, outlines and critically analyzes the provisions incorporated into the Act, and reflects on the potential long-term impact the Act would have should it be successful in becoming law.

Key Points
A Novel Treatment for Convex Lateral Crura: The Inverted Spanning Suture
Authors: Caropreso Carlos Alberto , Porpino Rafael , Neves José Carlos , Ichiba Gabriela , Hirotani Paula , Carvalho Victor , Souza Maria Carolina , Rodrigues José Luiz
Published: April 2024

Rhinoplasty is one of the most complex and challenging procedures in plastic surgery, even for experienced surgeons. Among the steps leading to an aesthetic and functional nose, there is the nasal tip improvement. Today's approach to nasal tip is the product of different techniques shifting through time, mainly from a resection tendency, to preservation and suture use to reshape cartilages. Addressing the lateral crura is vital to an aesthetic nasal tip and it is frequently obtained by adequate suture techniques. The alar-spanning suture described by Perkins is one of such. Regardless of its importance, it was not able to improve convex crura in some cases. The inverted alar-spanning suture (ISS) is an adaptation designed to treat those cases with the suture alone. ISS is a novel technique that can lead to better results treating the convex lateral crura by distributing the force vector in a more effective way. New techniques in rhinoplasty have multiplied, bringing this procedure to a new level and keeping up with the updated notion of restoration instead of excision the ISS is a new, precise, approach to an old problem.
Diagnostic Approach to Interstitial Lung Diseases Associated with Connective Tissue Diseases
Authors: Zamora Ana C. , Wesselius Lewis J. , Gotway Michael B. , Tazelaar Henry D. , Diaz-Arumir Alejandro , Nagaraja Vivek
Published: April 2024

Interstitial lung disorders are a group of respiratory diseases characterized by interstitial compartment infiltration, varying degrees of infiltration, and fibrosis, with or without small airway involvement. Although some are idiopathic (e.g., idiopathic pulmonary fibrosis, idiopathic interstitial pneumonias, and sarcoidosis), the great majority have an underlying etiology, such as systemic autoimmune rheumatic disease (SARD, also called Connective Tissue Diseases or CTD), inhalational exposure to organic matter, medications, and rarely, genetic disorders. This review focuses on diagnostic approaches in interstitial lung diseases associated with SARDs. To make an accurate diagnosis, a multidisciplinary, personalized approach is required, with input from various specialties, including pulmonary, rheumatology, radiology, and pathology, to reach a consensus. In a minority of patients, a definitive diagnosis cannot be established. Their clinical presentations and prognosis can be variable even within subsets of SARDs.
Identifying Barriers to The Implementation of Communicating Narrative Concerns Entered by Registered Nurses, An Early Warning System SmartApp
Authors: Hobensack Mollie , Withall Jennifer , Douthit Brian , Cato Kenrick , Dykes Patricia , Cho Sandy , Lowenthal Graham , Ivory Catherine , Yen Po-Yin , Rossetti Sarah
Published: April 2024

Background Nurses are at the frontline of detecting patient deterioration. We developed Communicating Narrative Concerns Entered by Registered Nurses (CONCERN), an early warning system for clinical deterioration that generates a risk prediction score utilizing nursing data. CONCERN was implemented as a randomized clinical trial at two health systems in the Northeastern United States. Following the implementation of CONCERN, our team sought to develop the CONCERN Implementation Toolkit to enable other hospital systems to adopt CONCERN.

Objective The aim of this study was to identify the optimal resources needed to implement CONCERN and package these resources into the CONCERN Implementation Toolkit to enable the spread of CONCERN to other hospital sites.

Methods To accomplish this aim, we conducted qualitative interviews with nurses, prescribing providers, and information technology experts in two health systems. We recruited participants from July 2022 to January 2023. We conducted thematic analysis guided by the Donabedian model. Based on the results of the thematic analysis, we updated the α version of the CONCERN Implementation Toolkit.

Results There was a total of 32 participants included in our study. In total, 12 themes were identified, with four themes mapping to each domain in Donabedian's model (i.e., structure, process, and outcome). Eight new resources were added to the CONCERN Implementation Toolkit.

Conclusions This study validated the α version of the CONCERN Implementation Toolkit. Future studies will focus on returning the results of the Toolkit to the hospital sites to validate the β version of the CONCERN Implementation Toolkit. As the development of early warning systems continues to increase and clinician workflows evolve, the results of this study will provide considerations for research teams interested in implementing early warning systems in the acute care setting.
Clarifying the impact of dual optical feedback on semiconductor lasers through analysis of the effective feedback phase
Authors: de Mey Robbe , Jolly Spencer W. , Virte Martin
Published: April 2024

Time-delayed optical feedback is known to trigger a wide variety of complex dynamical behavior in semiconductor lasers. Adding a second optical feedback loop is naturally expected to further increase the complexity of the system and its dynamics, but due to interference between the two feedback arms, it was also quickly identified as a way to improve the laser stability. While these two aspects have already been investigated, the influence of the feedback phases, i.e., sub-wavelength changes in the mirror positions, on the laser behavior still remains to be thoroughly studied, despite indications that this parameter could have a significant impact. Here, we analyze the effect of the feedback phase on the laser stability in a dual-feedback configuration. We show an increased sensitivity of the laser system to feedback phase changes when two-feedback loops are present and clarify the interplay between the frequency shift induced by the feedback and the interferometric effect between the two feedback arms.
Nonhydrostatic internal waves in the presence of mean currents and rotation
Authors: McCarney Jordan
Published: April 2024

In this paper we present a new exact solution that represents a Pollard-like, three-dimensional, nonlinear internal wave propagating on a non-uniform zonal current in a nonhydrostatic ocean model. The solution is presented in Lagrangian coordinates, and in the process we derive a dispersion relation for the internal wave which is subjected to a perturbative analysis which reveals the existence of two distinct modes of wave motion.
New dynamic diamond anvil cell for time-resolved radial x-ray diffraction
Authors: Huston L. Q. , Miyagi L. , Husband R. J. , Glazyrin K. , Kiessner C. , Wendt M. , Liermann H. P. , Sturtevant B. T.
Published: April 2024

The dynamic diamond anvil cell (dDAC) is a recently developed experimental platform that has shown promise for studying the behavior of materials at strain rates ranging from intermediate to quasi-static and shock compression regimes. Combining dDAC with time-resolved x-ray diffraction (XRD) in the radial geometry (i.e., with incident x-rays perpendicular to the axis of compression) enables the study of material properties such as strength, texture evolution, and deformation mechanisms. This work describes a radial XRD dDAC setup at beamline P02.2 (Extreme Conditions Beamline) at DESY’s PETRA III synchrotron. Time-resolved radial XRD data are collected for titanium, zirconium, and zircon samples, demonstrating the ability to study the strength and texture of materials at compression rates above 300 GPa/s. In addition, the simultaneous optical imaging of the DAC sample chamber is demonstrated. The ability to conduct simultaneous radial XRD and optical imaging provides the opportunity to characterize plastic strain and deviatoric strain rates in the DAC at intermediate rates, exploring the strength and deformation mechanisms of materials in this regime.
Multiplicity and limit of solutions for logarithmic Schrödinger equations on graphs
Authors: Shao Mengqiu , Yang Yunyan , Zhao Liang
Published: April 2024

Let Ω be a finite connected subset of a locally finite graph G = (V, E) with the vertex set V and the edge set E. We investigate the logarithmic Schrödinger equation on Ω with the nonlinear term |u|p−2u log u2. For p > 2, through two different approaches which are the Brouwer degree theory and mountain-pass theorem, we obtain the existence of ground state solutions. We also apply the Brouwer degree theory together with the constraint variational method to prove that the equation admits a sign-changing solution which implies the multiplicity of solutions to the equation. Finally, we illustrate that as p → 2, up to a subsequence, the solutions for p > 2 shall converge to a non-trivial solution of the equation with p = 2.
Optically pumped stimulated emission in HgCdTe-based quantum wells: Toward continuous wave lasing in very long-wavelength infrared range
Authors: Rumyantsev V. V. , Mazhukina K. A. , Utochkin V. V. , Kudryavtsev K. E. , Dubinov A. A. , Aleshkin V. Ya. , Razova A. A. , Kuritsin D. I. , Fadeev M. A. , Antonov A. V. , Mikhailov N. N. , Dvoretsky S. A. , Gavrilenko V. I. , Teppe F. , Morozov S. V.
Published: April 2024

Amplified interband emission within the 14–24 μm range is investigated in HgCdTe-based quantum wells under optical pumping. Carrier lifetimes are shown to be marginally limited only by Shockley–Read–Hall recombination, fully realizing the advantage of relativistic energy spectra of 2D HgCdTe in terms of suppressing the Auger processes. By carefully optimizing the waveguides and mitigating carrier heating, we achieve amplification thresholds as low as 1.5–2 W/cm2 at a pulse duration of 20–500 μs. With last generation quantum cascade lasers used for optical pumping, we estimate that continuous-wave HgCdTe lasers can operate in the very long-wavelength range (15–30 μm) and beyond.
T-wave inversion through inhomogeneous voltage diffusion within the FK3V cardiac model
Authors: Angelaki E. , Lazarides N. , Barmparis G. D. , Kourakis Ioannis , Marketou Maria E. , Tsironis G. P.
Published: April 2024

The heart beats are due to the synchronized contraction of cardiomyocytes triggered by a periodic sequence of electrical signals called action potentials, which originate in the sinoatrial node and spread through the heart’s electrical system. A large body of work is devoted to modeling the propagation of the action potential and to reproducing reliably its shape and duration. Connection of computational modeling of cells to macroscopic phenomenological curves such as the electrocardiogram has been also intense, due to its clinical importance in analyzing cardiovascular diseases. In this work, we simulate the dynamics of action potential propagation using the three-variable Fenton–Karma model that can account for both normal and damaged cells through a the spatially inhomogeneous voltage diffusion coefficient. We monitor the action potential propagation in the cardiac tissue and calculate the pseudo-electrocardiogram that reproduces the R and T waves. The R-wave amplitude varies according to a double exponential law as a function of the (spatially homogeneous, for an isotropic tissue) diffusion coefficient. The addition of spatial inhomogeneity in the diffusion coefficient by means of a defected region representing damaged cardiac cells may result in T-wave inversion in the calculated pseudo-electrocardiogram. The transition from positive to negative polarity of the T-wave is analyzed as a function of the length and the depth of the defected region.
On a nonlocal integral operator commuting with the Laplacian and the Sturm–Liouville problem: Low rank perturbations of the operator
Authors: Hermi Lotfi , Saito Naoki
Published: April 2024

We reformulate all general real coupled self-adjoint boundary value problems as integral operators and show that they are all finite rank perturbations of the free space Green’s function on the real line. This free space Green’s function corresponds to the nonlocal boundary value problem proposed earlier by Saito [Appl. Comput. Harmon. Anal. 25, 68–97 (2008)]. We prove these perturbations to be polynomials of rank up to 4. They encapsulate in a fundamental way the corresponding boundary conditions.
Electrical control of metal–insulator transition and magnetism in asymmetric multiferroic InCrX3 (X = S, Se) monolayers
Authors: Wu Yangyang , Cao Lei , Li Guannan , Huang Xiaokun , Zhang Bingwen , Gao Benling , Song Guang
Published: April 2024

Electrical control of conductivity and magnetism in two-dimensional (2D) ferroelectric (FE) materials have attracted immense attention due to their fascinating properties and potential applications in designing field-effect transistors and high-density multistate data storage. Based on first-principles calculations and crystal field theory, we present an approach to obtain 2D intrinsic asymmetric multiferroics by replacing the In atom in the ferroelectric In2X3 monolayer (X = S, Se) with the Cr atom. Interestingly, it is found that the InCrX3 monolayers have two inequivalent polarized states, which are characterized by metal and semiconductor, respectively, which is related to the crystal field around Cr3+ ions. Thus, it provides a feasible way to realize electrical control of reversible metal–insulator transition induced by ferroelectric switching, indicating that the InCrX3 monolayers can be used as the channel materials in the FE memory technology. In addition, because of the existence of the Cr3+ ions, the InCrX3 monolayers also exhibit robust ferromagnetism with different Curie temperatures and magnetocrystalline anisotropy energies, which can provide a good platform for realizing the strong coupling between the magnetism and ferroelectricity. These interesting results provide a feasible way to design asymmetric FE materials with regulatable conductivity and magnetism that can enable a wide range of applications in nanodevices.
All-optical measurement of magnetic fields for quantum gas experiments
Authors: Pomjaksilp Suthep , Schmidt Sven , Thielmann Aaron , Niederprüm Thomas , Ott Herwig
Published: April 2024

We present an all-optical method to measure and compensate for residual magnetic fields present in a cloud of ultracold atoms trapped in an optical dipole trap. Our approach leverages the increased loss from the trapped atomic sample through electromagnetically induced absorption. Modulating the excitation laser provides coherent sidebands, resulting in a Λ-type pump–probe scheme. Scanning an additional magnetic offset field leads to pairs of sub-natural linewidth resonances, whose positions encode the magnetic field in all three spatial directions. Our measurement scheme is readily implemented in typical quantum gas experiments and has no particular hardware requirements.
Parametrized ion-distribution model for extended x-ray absorption fine-structure analysis at high-energy-density conditions
Authors: Chin D. A. , Nilson P. M. , Ruby J. J. , Bunker G. , Ghosh M. , Signor M. E. , Bishel D. T. , Smith E. A. , Coppari F. , Ping Y. , Rygg J. R. , Collins G. W.
Published: April 2024

Experiments today can compress solids near isentropically to pressures approaching 100 × 106 atmospheres; however, determining the temperature of such matter remains a major challenge. Extended x-ray absorption fine-structure (EXAFS) spectroscopy is one of the few techniques sensitive to the bulk temperature of highly compressed solid matter, and the validity of this temperature measurement relies on constraining the local ion structure from the EXAFS spectrum. At high-energy-density (HED) conditions, the local ion structure often becomes distorted, which must be accounted for during the EXAFS analysis. Described here is a technique, using a parametrized ion-distribution model to directly analyze EXAFS spectra that provides a better constraint on the local structure than traditional second- or third-order cumulant expansion techniques at HED conditions. The parametrized ion-distribution model is benchmarked by analyzing EXAFS spectra from nickel molecular-dynamics simulations at ∼100 GPa and shown to provide a 10%–20% improvement in constraining the cumulants of the true ion distribution.
Onset of tetrahedral interstitial formation in GaAsN alloys
Authors: Cooper J. J. P. , Jen T. , Novak A. , Xi Z. , Qi L. , Naab F. U. , Wang Y. Q. , Goldman R. S.
Published: April 2024

N incorporation mechanisms in GaAs1−xNx alloys are probed using combined experimental and computational Rutherford backscattering spectrometry and nuclear reaction analysis angular yield scans. For xN < 0.025, in addition to substitutional nitrogen, NAs, (N-N)As, and (N-As)As split-interstitials are observed. However, for xN ≥ 0.025, evidence for N tetrahedral interstitials, Ntetra, emerges. We propose a mechanism for stabilization of Ntetra in which the elastic interaction between Ntetra and NAs is induced by the opposite signs of their misfit volumes. This work opens opportunities for exploring the formation of Ntetra and its influence on the properties of a variety of highly mismatched alloys.
Unraveling of the Lindblad equation of N coupled oscillators into N independent ones
Authors: Moreno J. , Pendse A. , Eisfeld A.
Published: April 2024

We consider a system of N bi-linearly coupled damped harmonic quantum oscillators with time-evolution governed by a Lindblad equation. We show that the corresponding stochastic quantum state diffusion equation can be transformed into a set of N independent damped harmonic oscillators. This offers a great reduction in the basis size. We investigate the numerical performance of the method and find, in particular, scaling laws for the number of stochastic trajectories needed to find a certain accuracy.
Improving AlGaN-based deep-ultraviolet light-emitting diodes: SiO2 passivation and size optimization for enhanced optoelectronic performance
Authors: Liu Zesen , Zhang Jianhong , Ye Jiandong , Shi Yating , Fu Jie , Wang Yiwang , Xu Weizong , Zhou Dong , Zhou Feng , Zhang Rong , Lu Hai , Ren Fang-Fang
Published: April 2024

The authors investigate 275-nm AlGaN-based deep-ultraviolet (DUV) light-emitting diodes (LEDs) of varied dimensions (100, 150, 200, and 300 μm) with or without SiO2 passivation. The results indicate SiO2 passivation significantly enhances the emission intensity and external quantum efficiency in smaller LEDs (100 μm) by mitigating sidewall defects and non-radiative recombination. Conversely, SiO2 passivation adversely affects larger LEDs (150, 200, and 300 μm) due to increased current crowding and heat accumulation. The study emphasizes the tradeoffs between sidewall optimization and heat management in micro-sized DUV LEDs. These insights are critical for the strategic development of efficient DUV LEDs tailored for practical applications.
English translation of Giesekus's famous article on flows with constant velocity gradient and the motion of particles suspended therein. Part I. Spatial flows
Authors: Abu-Farah Laila , Germann Natalie
Published: April 2024

Within the framework of a statistical rheology of suspensions, emulsions, and solutions, it is important to obtain an overview of the total set of flows with a constant velocity gradient. Therefore, the solutions of the differential equations of such flows are given and discussed especially with respect to the influence of the deformation and rotation parts of the velocity gradient. Subsequently, the motion of rigid particles in these flows is analyzed. Both the flow types themselves and the types of motion of the suspended particles can be divided into two broad classes. Among those with predominant deformation influence, we have hyperbolic–parabolic flows as well as a setting of the particles in fixed directions. Among those with predominant rotational influence, we have elliptical–spiral flows as well as a non-uniform orbital motion of the particles. The change from one place of motion to the other depends not only on the shape of the flow but also on the shape of the particles. Deformation becomes stronger as the form anisotropy of the particles increase.
Health status monitoring of bridge cable and telescopic compensation device based on fiber grating sensing array
Authors: Xu Chunying , Wu Xinjie , Zhou Yu , Liang Ruixin , Cao Chen , Chen Jiangwang , Zheng Xinlong , Lu Zhifei , Wei Chuliang
Published: April 2024

Laying power cables along the bridge is a new way of laying submarine cables across the sea. Monitoring the health status of cables and their telescopic compensation devices is necessary. In this study, fiber grating sensing technology was used to monitor the strain, temperature, and vibration of the bridge cable of the Zhoushan–Daishan Bridge in Zhoushan, Zhejiang Province, and its compensation device. Two typhoons and one invasion event happened during the monitoring period. Temperature signals, strain signals, and time domain and time–frequency domain vibration signals were analyzed. The results showed that no fire hazards or risk of external damage were found with the bridge cable, and the monitoring system filled a gap in the in situ monitoring of the bridge cable in the Zhoushan–Daishan Bridge by the State Grid.
Time-resolved biphase signatures of quadratic nonlinearity observed in coupled Alfvén eigenmodes on the DIII-D tokamak
Authors: Riggs G. , Koepke M. , Heidbrink W. , Van Zeeland M. A. , Spong D.
Published: April 2024

We report the detection of nonstationary quadratic coupling between toroidicity-induced Alfvén eigenmodes (TAEs) on sub-millisecond time scales. Identification of phase coherency between multiple TAEs and nonlinearly generated modes is facilitated by wavelet-based bicoherence analysis of time-series from inductive coils, taken from a DIII-D discharge heated by neutral beam injection (NBI). Characterization of nonlinear three-wave interaction is inferred by stationary local bispectrum phase (biphase) and confirmed via bandpass filtering. Biphase dynamics associated with prominent bispectral features are well-resolved in time and consistent with transient quadratic coupling. Onset and duration of nonlinearity are correlated with enhanced amplitude of participating TAEs; coincident changes in amplitude are observed for modes at difference frequency |fTAE,1−fTAE,2|.
Viscous compressible flow from a semi-sealed porous system: Mechanisms and wave-mediated diffusion
Authors: Jin Yan , Wei Shiming , Xia Yang , Chen Kang Ping
Published: April 2024

It is widely known that a low Mach number gas flow can be approximated as incompressible at the leading order in a small Mach number expansion of the full solution. However, it has been shown recently that such an incompressible approximation becomes invalid for a semi-sealed system with no inlets and no boundary movements. Studies based on linearized compressible Navier–Stokes equations for such a system made of small capillary tubes have revealed some counter-intuitive flow characteristics such as no-slip flow with a slip-like mass flow rate. Here, we extend these works to gas drainage from a semi-sealed porous system. It is shown that gas drainage is solely driven by its volumetric expansion, and it cannot be approximated as an incompressible flow modulated by a small compressible effect. At the pore-scale, gas motion is governed by a damped rarefaction wave, and multiple scattering of the wave leads to an effective diffusion of the gas at the macroscopic scale. A large number of pore-scale simulations are performed for various pore structures, and the results are used to extract the macroscopic wave-mediated effective diffusion coefficient. Experiments are carried out to validate the wave-mediated effective diffusion model. The flow rates predicted by the effective diffusion model agree well with the experiments while results based on Darcy's law severely underestimate the flow rate. It is established that Darcy's law cannot be applied to a semi-sealed system, and no-slip flow with a slip-like flow rate is inherently embedded in the compressible Navier–Stokes equations.
Exact periodic solution family of the complex cubic-quintic Ginzburg–Landau equation with intrapulse Raman scattering
Authors: Zhou Yuqian , Zhang Qiuyan , Li Jibin , Yu Mengke
Published: April 2024

In this paper, we consider the exact solutions of the complex cubic-quintic Ginzburg–Landau equation. By investigating the dynamical behavior of solutions of the corresponding traveling wave system of this PDE, we derive exact explicit parametric representations of the periodic wave solutions under given parameter conditions.
Collective response in planar random-flip coherent metasurface by modulating multipole moments
Authors: Sun Botian , Zheng Kaihao , Jiang Zhaoqi , Li Wenjia , Lv Bo , Li Yuxiang , Zhu Zheng , Guan Chunying , Shi Jinhui
Published: April 2024

We numerically and experimentally investigate collective resonant responses of coherent metasurfaces consisting of planar random-flip asymmetrically split rings. The collective narrow band response becomes broader and eventually disappears with increasing the percentage of flipped split rings. The exploited physical mechanism is the degraded collective response due to random microscopic multipole excitation. Our study provides a method to construct random metasurfaces and is helpful to have an insight into their underlying physics.
Study on rotor–stator interaction in a pump-jet propulsor based on dynamic mode decomposition
Authors: Li Huiyao , Wang Jiaqi , Zhang Junyue , Zhang Zhenguo , Hua Hongxing
Published: April 2024

For a pre-swirl pump-jet propulsor (PJP), the stator inevitably induces the problem of rotor–stator interaction (RSI). In this paper, the mechanism of RSI in a PJP is analyzed through dynamic mode decomposition (DMD). The coherent flow structures and corresponding frequencies have been decomposed and analyzed. The results show that the dominant frequencies of pressure fluctuation in the stationary domain are BPF (rotor blade passing frequency) and its multiples. In contrast, the dominant frequencies in the rotational domain are SPF (stator passing frequency) and its multiples. The frequencies of k*SF (SF, shafting frequency; k = 4, 5, and 8) have also been found. The mode structure corresponding to the SPF is stable and has the highest mode energy. The reconstruction residual formula is introduced, and the axial velocity flow field is reconstructed well by the DMD modes compared with the raw flow field. This research can provide a reference for studying and suppressing RSI in a PJP.
Investigation of vortex-induced vibrations of rotating cylinders with different surface roughnesses
Authors: Chen Wei , Du Aoyue , Lin Yongshui , Shao Jiangyan , Gu Jian , Gong Jie , Rheem Chang-Kyu , Wen Binrong , Li Xiaobin
Published: April 2024

The vortex-induced vibrations of a two-degree-of-freedom rough rotating cylinder at a low Reynolds number of 200 and a mass ratio of 2.6 are investigated via numerical simulations. The relevant calculation parameters are as follows: a rotation rate between zero and one, surface roughness height between 0% and 15%, and reduced velocity between 1 and 12. It is found that reasonable rough surface and rotational motion of the smooth cylinder are two effective factors for suppressing the vortex-induced vibration (VIV) response. Conversely, a rotating cylinder with a rough surface enhances the VIV response. Four wake patterns (2S, P + S, 2P, and multiple vortices patterns) are captured. At low rotation rates, with increasing roughness height, the wake pattern develops into a multiple vortex pattern after multiple evolutions. The variation in roughness at a high rotation rate does not correlate with a change in the wake pattern. The area of the cylindrical motion trajectory is positively correlated with the roughness height, and the time-averaged dimensionless displacements of the cross-flow and in-line flow directions increase with increasing roughness height.