bluuebunny/crossref_metadata_2025 huggingface dataset:
Detection of a high-velocity sodium feature on the ultra-hot Jupiter WASP-121 b
Authors: Seidel J. V. , Borsa F. , Pino L. , Ehrenreich D. , Stangret M. , Zapatero Osorio M. R. , Palle E. , Alibert Y. , Allart R. , Bourrier V. , Di Marcantonio P. , Figueira P. , González Hernández J. I. , Lillo-Box J. , Lovis C. , Martins C. J. A. P. , Mehner A. , Molaro P. , Nunes N. J. , Pepe F. , Santos N. C. , Sozzetti A.
Published: April 2023

Context. Ultra-hot Jupiters, with their high equilibrium temperatures and resolved spectral lines, have emerged as a perfect testbed for new analysis techniques in the study of exoplanet atmospheres. In particular, the resolved sodium doublet as a resonant line has proven a powerful indicator to probe the atmospheric structure over a wide pressure range.

Aims. We aim to explore an atmospheric origin of the observed blueshifted feature next to the sodium doublet of the ultra-hot Jupiter WASP-121 b using a partial transit obtained with the 4-UT mode of ESPRESSO. We intend to study its atmospheric dynamics visible across the terminator by splitting the data into mid-transit and egress.

Methods. We explored the impact of the Rossiter-McLaughlin effect on the line shape of the sodium doublet. The partial transit is separated into one dataset centred around mid-transit and one dataset comprising the second part of the transit and egress. Lastly, the atmospheric retrieval code, Multinested Eta Retrieval Code (MERC), was applied to both datasets in order to study the imprint of atmospheric dynamics on the line shape of the sodium doublet.

Results. We determine that the blueshifted high-velocity absorption component is generated only during the egress part of the transit when a larger fraction of the day side of the planet is visible. For the egress data, MERC retrieves the blueshifted high-velocity absorption component as an equatorial day-to-night side wind across the evening limb, with no zonal winds visible on the morning terminator with weak evidence compared to a model with only vertical winds. For the mid-transit data, the observed line broadening is attributed to a vertical, radial wind.

Conclusions. We attribute the equatorial day-to-night-side wind over the evening terminator to a localised jet and restrain its existence between the substellar point and up to 10° to the terminator in longitude, an opening angle of the jet of at most 60° in latitude, and a lower boundary in altitude between [1.08, 1.15] Rp. As a hypothesis, we propose that the jet is produced by the excitation of standing planetary scale Rossby waves by stellar irradiation and subsequently broken by Kelvin-Helmholtz instabilities. Due to the partial nature of the transit, we cannot make any statements on whether the jet is truly super-rotational and one-sided or part of a symmetric day-to-night-side atmospheric wind from the hotspot.
Impact assessment of biomass burning in Southeast Asia to 2019 annual average PM2.5 concentration in Thailand using atmospheric chemical transport model
Authors: Chantaraprachoom Nanthapong , Mochizuki Daichi , Shimadera Hikari , Luong Mui Viet , Matsuo Tomohito , Kondo Akira
Published: April 2023

Agricultural residues burning as a means of land preparation commonly practiced in many Southeast Asian countries causes significant deterioration of ambient air quality and public health. In this study, WRF-CMAQ Atmospheric Chemical Transport Model was used to conduct a year-round simulation (1 January - 31 December 2019) of PM2.5 spatio-temporal variation over Southeast Asia. The model utilized the Fire emission Inventory from NCAR (FINNv1.5) from National Center for Atmospheric Research (NCAR) as a biomass burning emission input. The model performance was evaluated by comparing simulated values with observed values from monitoring stations in nine major cities. The model shows acceptable performance reproducing the PM2.5 concentration with 14.9% normalized mean bias (NMB) and correlation coefficient of 0.89. After that, the simulation was conducted again with emission from FINNv1.5 turned off. The results from FINNv1.5 on and off cases were then compared to evaluate contribution of biomass burning to PM2.5 concentration in two major cities of Thailand: Bangkok and Chiang Mai. The comparison shows that biomass burning contributes to 49.1% and 13.1% of PM2.5 annual average concentration in Chiang Mai and Bangkok respectively with highest month being April for Chiang Mai (70.7% contribution) and March for Bangkok (35.5% contribution).
Perovskite materials for photovoltaics: a review
Authors: Beepat Kevin , Kumar Sanjay , Sharma Ankush , Sharma Davinder Pal , Pathak Dinesh , Nunzi Jean-Michel
Published: April 2023

Photovoltaic is among the most propitious renewable energy sources for meeting global energy demands. Owing to their simple solution synthesis procedure, lightweight, wearable, power conversion efficiency, flyable, ready to deploy for extremist lightweight space, and reduced cost of constituent materials, perovskite solar cells have gotten huge interest in the past years. Because of the high-quality perovskite film attained by low-temperature fabrication methods, as well as the development of appropriate interface and electrode materials, the effectiveness of perovskite solar cells (PSCs) has topped 25% efficiency in recent years. Furthermore, perovskite solar cells' stabilization has gotten a lot of well-deserved recognition. The future of various carbon, tin, and polymer materials-based perovskite solar cells has even been explored, as well as their industrial expansion possibility are also discussed. This review paper summarizes important accomplishments to date, highlights the unique properties of these perovskites that have led to their fast upsurge, and highlights the problems that must be overcome for perovskite solar cells to be developed and commercialized successfully.
Study on the influence of the shape and properties of Q345R welded joints on stress concentration and fatigue life
Authors: Ma Rui , Zhang Yu , Zhao Jun , Zhang Chenxing
Published: April 2023

For the commonly used pressure vessel material Q345R, the theoretical formulas of stress concentration factor (SCF) and fatigue life of welded joints were derived. A finite element analysis model was established to systematically study the theoretical SCF and fatigue life of the joint. The results show that the theoretical SCF increases by 45% with the increase of reinforcement height and decreases by 9.9% with the increase of fillet radius. In addition, the weld width and wire material have no effect on SCF. The fatigue tests of three typical welded specimens were carried out. The experimental results were basically consistent with the finite element analysis results, which proved the reliability of the analysis model and provided theoretical guidance for the actual detection and evaluation.
Die Frenzelbrille
Authors: Pudszuhn Annett , John Peggy , Schönfeld Uwe , Münst Julia , Scherer Hans
Published: April 2023

Eine Untersuchung mit der Frenzelbrille steht am Anfang jeder Untersuchung bei Patienten mit Schwindelbeschwerden und ist wichtig bei gutachterlichen Untersuchungen. Der Entwickler der Brille, Herrmann Frenzel, hat bereits darauf hingewiesen, dass sie nur im stark abgedunkelten Raum oder besser bei totaler Dunkelheit verwendet werden sollte, denn in heller Umgebung ist für den Patienten eine Fixation möglich. Im klinischen Alltag ist diese idealisierte Untersuchungsumgebung jedoch sehr selten gegeben.

Wir haben untersucht, wie groß der Fehler bei der Untersuchung im Hellen im Vergleich zu einer Untersuchung unter optimalen Bedingungen ist. Dazu erzeugten wir einen Nystagmus durch Pendelstuhlreizung mit unterschiedlichen Beschleunigungen. Dieser wurde elektronystagmografisch aufgezeichnet, mit einer an die Frenzelbrille angekoppelten Videokamera wurde untersucht, bei welchem Beschleunigungsreiz ein Nystagmus mit der Frenzelbrille in heller Umgebung oder in kompletter Dunkelheit detektiert wird. Im Durchschnitt von 10 untersuchten gesunden Personen wird ein Nystagmus im ENG bei einer Beschleunigung vom 1,13°/s2 entdeckt, mit der Frenzelbrille in Dunkelheit erst beim mehr als 3-fachen Wert von 3,8°/s2, im Hellen benötigt man eine nahezu 8-fache (7,95°/s2) Beschleunigung, um den Nystagmus zu erkennen. Eine Person musste mit 15,7°/s2 beschleunigt werden, um im Hellen einen Nystagmus festzustellen. Dieses Ergebnis zeigt, dass bei fehlenden Dunkelräumen eine Frenzelbrille nicht geeignet ist, als diagnostisches Mittel zu dienen. Hier muss zukünftig auf eine Videonystagmusbrille, am besten mit Bluetooth-Technik zur Befunddokumentation ausgewichen werden.
Starten Sie mit einem Sofa! – Betätigungsorientierte Therapieräume
Authors: Bräuter Theresa
Published: April 2023

Zwischen gesetzlichen Richtlinien, wie eine ergotherapeutische Praxis ausgestattet sein muss, und dem Wunsch nach betätigungsorientiertem Arbeiten liegen oft Welten. Theresa Bräuter zeigt, wie eine Praxis so gestaltet sein kann, dass eine moderne Arbeitsweise möglich wird.
Nebenwirkungen von Kosmetika: Wie Dermatologen Patienten unterstützen können, ihre Rechte wahrzunehmen
Authors: Elsner Peter Ulrich
Published: April 2023

Kosmetische Mittel sind nach Art. 2 der EU-Kosmetik-Verordnung „Stoffe oder Gemische, die dazu bestimmt sind, äußerlich am Körper des Menschen oder in seiner Mundhöhle angewendet zu werden mit dem Zweck, Haut, Haare, Nägel, Lippen, die äußeren Intimregionen oder die Zähne und die Mundschleimhäute zu reinigen, zu schützen, in gutem Zustand zu erhalten, zu parfümieren, deren Aussehen zu verändern oder den Körpergeruch zu beeinflussen“. Sie dürfen die menschliche Gesundheit nicht schädigen, wenn sie unter „normalen oder vernünftigerweise vorhersehbaren Bedingungen“ angewandt werden.

Gleichwohl kommt es zu unerwünschten Wirkungen von Kosmetika, wobei irritative und allergische Kontaktekzeme am häufigsten auftreten. Bevölkerungsbasierte Daten zur Inzidenz unerwünschter Kosmetikwirkungen sind allerdings nicht verfügbar. Eine Pflicht für Kosmetikhersteller zur aktiven Information der Öffentlichkeit über Nebenwirkungsmeldungen existiert nicht.

Patienten, die unerwünschte Wirkungen von Kosmetika erleiden, können gegen den Hersteller oder Händler Ansprüche auf Schadensersatz und/oder Schmerzensgeld nach dem Produkthaftungsgesetz geltend machen. Dermatologen sollten sie dabei durch eine gute Beweissicherung, insbesondere in Form einer dermatologischen Befunddokumentation und ggf. einer allergologischen Testung verdächtiger Produkte unterstützen.

Schwere unerwünschte Wirkungen von Kosmetika sollten unabhängig davon, dass keine Meldepflicht besteht, an die Kosmetik-Überwachungsbehörden gemeldet werden, um die Sicherheit kosmetischer Produkte zu verbessern.
Indole Alkaloids of Rauvolfia ligustrina and Their Anxiolytic Effects in Adult Zebrafish
Authors: de Sousa Herbert Magalhães , da Silva Alison Batista , Ferreira Maria Kueirislene Amâncio , da Silva Antonio Wlisses , de Menezes Jane Eire Silva Alencar , Marinho Emmanuel Silva , Marinho Márcia Machado , dos Santos Helcio Silva , Pessoa Otilia Deusdênia Loiola
Published: April 2023

Rauvolfia species are well known as producers of bioactive monoterpene indole alkaloids, which exhibit a broad spectrum of biological activities. A new vobasine-sarpagan-type bisindole alkaloid (1) along with six known monomeric indoles (2, 3/4, 5, and 6/7) were isolated from the ethanol extract of the roots of Rauvolfia ligustrina. The structure of the new compound was elucidated by interpretation of their spectroscopic data (1D and 2D NMR and HRESIMS) and comparison with published data for analog compounds. The cytotoxicity of the isolated compounds was screened in a zebrafish (Danio rerio) model. The possible GABAergic (diazepam as the positive control) and serotoninergic (fluoxetine as the positive control) mechanisms of action in adult zebrafish were also evaluated. No compounds were cytotoxic. Compound 2 and the epimers 3/4 and 6/7 showed a mechanism action by GABAA, while compound 1 showed a mechanism action by a serotonin receptor (anxiolytic activity). Molecular docking studies showed that compounds 2 and 5 have a greater affinity by the GABAA receptor when compared with diazepam, whereas 1 showed the best affinity for the 5HT2AR channel when compared to risperidone.
Results after Tricuspid Valve Surgery for Preserved and Dysfunctional Right Ventricle
Authors: Park Eun-Ah , Hwang Ho Young , Choi Jae Woong , Kim Ji Seong , Kang Yoonjin , Sohn Suk Ho , Kim Kyung Hwan
Published: April 2023

Background This study aimed to compare long-term outcomes after tricuspid valve (TV) repair (TVr) with those after TV replacement (TVR) by adjusting the right ventricular (RV) volume and function.

Methods We enrolled 147 patients who underwent TVr (n = 78) and TVR (n = 69) for grade 3 or 4 tricuspid regurgitation and had preoperative cardiac magnetic resonance data. Long-term clinical outcomes were compared between the two groups using inverse probability treatment weighting (IPTW) to adjust for differences in preoperative characteristics between the two groups. Subgroup analyses were performed in patients with preserved and dysfunctional RV (ejection fraction < 50%).

Results There were no significant differences in operative mortality or postoperative complications between the two groups before and after the IPTW adjustment. Five- and 10-year overall survival rates were 84.2 and 67.1%, respectively. Five- and 10-year cumulative incidences of TV-related events (TVREs) were 33.1 and 55.6%, respectively. There were no significant differences in overall survival and cumulative incidence of TVREs after IPTW adjustment (p = 0.236 and p = 0.989, respectively). The risk-adjusted overall survival was marginally higher in the TVr group of patients with preserved RV function (p = 0.054), while no such significant difference was found between the two groups of patients with dysfunctional RV (p = 0.513).

Conclusion Adjusted long-term clinical outcomes after TVr and TVR were comparable. TVr might be beneficial for patients with preserved RV function in terms of long-term survival; however, this benefit might disappear in patients with RV dysfunction.
Cross-Coupling Reactions between Alkenes by C–H Cyclometalation
Authors: Xie Kailin , Zhang Jian , Lu Xi , Wang Yini
Published: April 2023

Alkenes are one of the most abundant raw feedstocks and are utilized to construct complex chemicals, whilst cross-coupling reactions using alkenes represents a powerful method toward valuable chemicals. In the past decade, cross-coupling reactions of simple alkenes by chelation-assisted alkenyl C–H functionalization has attracted significant attention due to its atom/step efficiency and excellent Z/E selectivity, proceeding by C–H exo-cyclometalation and endo-cyclometalation. In this account, we summarize transition-metal-catalyzed cross-coupling reactions between alkenes to generate 1,3-dienes via C–H alkenylation,1,4-dienes through C–H allylation, multisubstituted alkenes via hydroalkenylation, and heterocycles by way of tandem alkenyl C–H functionalization/annulation. Asymmetric alkenyl C–H alkenylation to prepare axially chiral aryl 1,3-dienes is also discussed.

1 Introduction

2 Alkenyl C–H Alkenylation

2.1 By endo-Cyclometalation

2.2 By exo-Cyclometalation

3 Alkenyl C–H Allylation

3.1 By endo-Cyclometalation

3.2 By exo-Cyclometalation

4 Alkenyl C–H Alkylation via Hydroalkenylation

5 Cascade Reactions

6 Conclusion
A Simple and Modular Access to 4-Mercapto-4-methylpentanoic Acid: A Useful Building Block in Antibody-Drug Conjugates Research
Authors: Serpier Fabien , Petit Laurent , Salamone Logan , Lepeintre Martin , Revil-Baudard Vincent L.
Published: April 2023

An efficient synthesis of 4-mercapto-4-methylpentanoic acid, a fragment notably found in Antibody-Drug Conjugates (ADCs), is reported using an intermolecular radical transfer reaction as the pivotal step. The reported approach displays several advantages over more traditional routes and is compatible with the chemistry involved in the construction of ADCs. Original analogues of the molecule of interest can be readily accessed using the method developed.
Quantifying 30 Years of Technological Innovation in Total Hip Arthroplasty
Authors: Kunze Kyle N. , Rullán Pedro J. , Potluri Ajay , Molloy Robert M. , Krebs Viktor E. , Piuzzi Nicolas S.
Published: April 2023

Technological innovation in total hip arthroplasty (THA) is a critical component of health care delivery for improving patient outcomes. Analyzing the content of patents and trends in their activity over time can leverage insight into innovations in THA; however, these investigations remain underutilized. We aimed to quantify patent activity and relative growth pertaining to technologies in THA over a 30-year period. A query for patents relating to “hip replacement” or “hip arthroplasty” between 1989 and 2019 using an open-source patent database yielded 24,071 unique patents for analysis. These were grouped into 12 independent technology clusters using Cooperative Patent Classification codes. Annual patent activity for each cluster was normalized with a validated formula to control for exponential growth. The 5-, 10-, and 30-year compound annual growth rates (CAGR) for each cluster were quantified and compared between clusters. Annual cumulative patent activity increased from 151 patents in 1989 to 1,182 patents in 2019, representing a 682.8% increase. The largest technology clusters concerned “drugs” (n = 6,429 patents), “instruments” (n = 4,014 patents), “materials” (n = 2,037 patents), and “components” (n = 1,946 patents). One-half of the identified clusters concerned developments in technology-assisted THA (patient-specific instrumentation, navigation, robotics, design/manufacturing, instruments, and computer modeling). The most rapidly growing technology within the past 5, 10, and 30 years was robotics (CAGR = 15.82%, 20.11%, and 9.50%, respectively). Within the past 5- and 10-year trial prostheses (CAGR = 10.76%) and design/manufacturing processes (CAGR = 10.27%), computer modeling (CAGR = 12.91%) and navigation (CAGR = 11.25%) were among the most rapidly growing clusters, respectively. The majority of patents pertaining to THA over the past 30 years have concerned developments in drugs, instruments, materials, and components. Within the past 10-years, substantial growth has been observed in patent domains related to technology-assisted THA. Monitoring of emerging technologies through patent metrics may provide valuable information for regulatory bodies and assess progress in the field of THA. This is a cross-sectional study with level of evidence IV.
Rechtskolumne: Bei gekündigtem Versorgungsvertrag kann Widerspruch sich lohnen
Authors: Weimer Tobias
Published: April 2023

Behörden können sich irren. Ein Streiten bis zur letzten Instanz kann von Erfolg gekrönt sein, wie das folgende Beispiel zur Kündigung eines Versorgungsvertrages durch Bescheid zeigt.
BMC-Kongress steht bevor: Transformation durch regionale Versorgung
Authors: Behmer Malte
Published: April 2023

Bringt der Trend zur Regionalisierung den lang ersehnten Durchbruch bei der Transformation der Gesundheitsversorgung hin zu mehr Patientenorientierung und integrierten Versorgungspfaden? Dafür benötigen Akteure vor Ort vor allem mehr Gestaltungsfreiheit und einen Vertrauensvorschuss. Der BMC-Kongress diskutiert Lösungswege.
Innovationspartnerschaft: „Wir werden gemeinsam alles digitalisieren“
Authors: Engberg Anna
Published: April 2023

Die Kooperation zwischen Nexus und der Johannesstift Diakonie steht seit Dezember 2022 in den Startlöchern. Das Novum: Statt auf Einzellizenzen setzt das Gesundheitsunternehmen auf eine Digital-Flatrate, um die zehn Krankenhausstandorte umfassend zu digitalisieren.
Patientensteuerung: Mehr Transparenz dank Teletracking
Authors: Reisinger Kathrin
Published: April 2023

Patientenströme leiten, Betten voll auslasten, OP-Kapazitäten, Reinigung und Transport in Echtzeit managen. Neue digitale Workflow-Systeme erobern derzeit den Markt. In aller Munde ist dabei unter anderem „Teletracking“. Im Vordergrund stehen dabei nicht die Systeme als IT-Plattform, sondern der grundlegende Wandel, den eine Klinik dafür bereit sein muss, „in Kauf“ zu nehmen – von dezentralisierten Planungen in Abteilungen hin zur Zentralisierung im gesamten Haus.
Nachwachsende Herzklappen: Langlebig und dicht
Authors: Lang Michael
Published: April 2023

Beim in situ Tissue Engineering erzeugen Forscher künstliche Herzklappen, die von Zellen des Prothesenträgers besiedelt werden. Das ursprüngliche Klappenmaterial löst sich mit der Zeit auf. Die Klappe besteht dann nur noch aus körpereigenen Zellen.
An improved resistance model of positive subsonic plasma channels in water
Authors: Zhang He , Liu Yi , Liu Hongji , Xu Youlai , Li Hua , Lin Fuchang
Published: April 2023

The subsonic plasma channel and water can be regarded as series resistors in the pre-breakdown stage of sub-millisecond pulsed discharge in conductive water. An improved resistance model of the positive subsonic plasma channel is proposed. The gap resistance and the morphology of the bubble cluster and the plasma channel inside it are obtained from the electrical measurement and optical observation, respectively. The resistance of the plasma channel in the strong-ionization stage is calculated using the small-current arc resistance model. The improved model of the water resistance is established by analyzing the relationship between its equivalent cross-sectional area and its length in an uneven electric field. The resistance of the plasma channel in the weak-ionization stage is calculated. The resistance, voltage, and energy in the gap are analyzed based on the improved resistance model. The plasma channel's resistance is far less than the water resistance. The low voltage drop in the plasma channel leads to a high electric potential in the plasma channel's head, which is conducive to the plasma channel's development. 97% of the total energy in the pre-breakdown stage is consumed by the water resistor. The improved resistance model is helpful to supplement the development mechanism of the sub-millisecond pulsed discharge in water.
High-performance gallium nitride high-electron-mobility transistors with a thin channel and an AlN back barrier
Authors: Zhang Yachao , Dong Yaolong , Chen Kai , Dang Kui , Yao Yixin , Wang Baiqi , Ma Jinbang , Liu Wenjun , Wang Xing , Zhang Jincheng , Hao Yue
Published: April 2023

In this work, high-performance high-electron-mobility transistors (HEMTs) with a thin GaN channel and an AlN back barrier were fabricated and investigated in detail. The AlN back barrier HEMTs possess a higher current density and a better linearity than traditional devices. In addition, the off-state leakage current of the AlN back barrier HEMTs is more than one order of magnitude lower than that of traditional devices with a high-resistance Fe-doped GaN buffer, even though they do not involve any intentional doping technique. Additionally, the high-temperature performance of the AlN back barrier HEMTs is excellent, with less attenuation in the drain current density and less increase in the off-state leakage current. Moreover, the breakdown voltage of the AlN back barrier HEMTs is as high as 309 V with an LGD of 2.5 μm, resulting in a high Baliga figure of merit of 0.354 GW/cm2. The superior performance of the AlN back barrier devices is further demonstrated by the calculation and simulation results. The results in this work not only show the great potential of AlN back barrier HEMTs but also provide a useful direction for overcoming the limiting issues of nitride devices.
Dislocation-related surface-layer effect in SrTiO3 single crystals
Authors: Li Yide , Liu Zhijie , Cao Wenjun , Huang Shouguo , Li Feng , Guo Youmin , Xu Yichun , Wang Chunchang
Published: April 2023

Oxygen vacancies (VOs) and their distribution can affect oxides' properties from various aspects. In this work, we present a dislocation-related surface-layer effect in single crystal SrTiO3 (STO). Our results from the first principles calculations based on density functional theory along with our experimental research based on angle-resolved x-ray photoelectron spectroscopy indicate that, in contrast with bulk STO where VOs tend to cluster in a line, as depth increases from surface region, the concentration of VOs increases first, reaches a maximum value, and then decreases to a saturation value. This effect was argued to be the combinative result of the oxygen-vacancy diffusion along the dislocation lines and the ambient oxygen-atom incorporation into the crystal.
Scalable exponentially complex representations of logical phi-bit states and experimental demonstration of an operable three phi-bit gate using an acoustic metastructure
Authors: Deymier P. A. , Runge K. , Cutillas P. , Hasan M. A. , Lata T. D. , Levine J. A.
Published: April 2023

Logical phi-bits are nonlinear acoustic modes analogous to qubits and supported by an externally driven acoustic metastructure. A correspondence is established between the state of three correlated logical phi-bits represented in a low-dimensional linearly scaling physical space and their state representation as a complex vector in a high-dimensional exponentially scaling Hilbert space. We show the experimental implementation of a nontrivial three phi-bit unitary operation analogous to a quantum circuit. This three phi-bit gate operates in parallel on the components of the three phi-bit complex state vector. While this operation would be challenging to perform in one step on a quantum computer, by comparison, ours requires only a single physical action on the metastructure.
Heat addition with variable area: Methodology for preliminary design of the scramjet combustion chamber
Authors: Carneiro R. , Passaro A. , Toro P. G. P.
Published: April 2023

Well-known analytical approaches are commonly adopted for the preliminary design of scramjet engines. In this context, the combustion process in the combustion chamber can be modeled by considering heat addition to the airflow at supersonic speed. The one-dimensional Rayleigh flow theory can be applied to estimate the behavior of thermodynamic properties and velocities when the combustion chamber has a constant cross-sectional area and no mass is added within the duct. However, the temperature and pressure predicted by using constant area combustion chambers are too high, implying the necessity of modifications in the cross-sectional area of the chamber to avoid thermal choking and excessive pressure gradients. In this case, the unidimensional Rayleigh theory does not fit anymore. This work proposes an analytical methodology to estimate the airflow thermodynamic properties and velocities for scramjet combustion chambers with cross sections of variable areas by using an iterative algorithm that employs the Rayleigh flow area ratio theory. The analytical results were compared with the two-dimensional computational fluid dynamics analysis using the Reynolds-averaged Navier–Stokes method for both inviscid and viscous flow and considering turbulence effects. The proposed analytical model to estimate the flow behavior in the scramjet combustion chamber predicted results in agreement with the physics of the problem and with the results obtained via numerical simulation. The analytical model cannot predict oscillations in the flow properties caused by the expansion waves and their reflections. Still, the behavior and intensity of the properties are well captured along the entire length of three combustion chambers with variable area. The proposed algorithm is also applied to determine the angle of the combustion chamber that allows guaranteeing a constant, or a quasi-constant, static pressure along the length of the combustion chamber, approaching better the ideal thermodynamic Brayton cycle. The proposed model is suitable for preliminary scramjet designs and can be used to solve other problems involving variable area ducts.
Extended emission wavelength beyond 2.2
μ
m in strained multiple-quantum-well laser using InGaAsSb material grown on InP substrate
Authors: Mitsuhara Manabu , Kobayashi Wataru , Shindo Takahiko , Nakajima Fumito
Published: April 2023

We report on the growth and lasing characteristics of 2.3%-compressive-strained InGaAsSb multiple-quantum-well (MQW) lasers on InP substrates with emission wavelengths near 2.2 μm. MQW structures with four wells were grown by metalorganic molecular beam epitaxy at 500 °C. X-ray diffraction and photoluminescence results showed that the InGaAsSb well layers were grown with the assistance of the Sb surfactant effect. The emission wavelengths of the MQW lasers with well thicknesses of 6.4 and 8.4 nm were 2.190 and 2.278 μm, respectively. For the MQW laser with the well thickness of 8.4 nm, the threshold current under continuous-wave operation was 22 mA at 15 °C, and the characteristic temperature was estimated to be 53 K in the temperature region from 15 to 35 °C and 42 K in the region from 35 to 55 °C. The laser with the 8.4-nm-thick well had an emission wavelength about 90 nm longer than that of the one with the 6.4-nm-thick well, but the lasing characteristics of the two were comparable.
Toroidal vs cylindrical analytical description of the magnetic field outside the elongated evolving plasma in tokamaks
Authors: Pustovitov V. D. , Chukashev N. V.
Published: April 2023

In the plasma equilibrium theory, Gajewski's analytical expression [Gajewski, Phys. Fluids 15, 70 (1972)] for the poloidal magnetic flux ψ outside the plasma is known. It was obtained as a solution of the two-dimensional Laplace equation outside an infinite straight cylinder with an elliptical cross section and a uniform current density j ζ. An example of its use for analysis of static configurations is given in the study by Porcelli and Yolbarsop [Phys. Plasmas 26, 054501 (2019)]. Here, we consider the question of its applicability in dynamic problems including, for example, the current quench (CQ) or vertical displacement event (VDE), when the electromagnetic response of the vacuum vessel to the plasma magnetic field evolution has to be accounted for. It is shown that the mentioned cylindrical model does not provide enough information for calculation of the current induced in the wall. Mathematically, this manifests itself in the fact that Gajewski's expression contains an indefinite constant of integration ψ b (hereinafter it is ψ at the plasma boundary), which, in analytical applications, is replaced either by zero or by a value that makes ψ = 0 on the magnetic axis. This does not affect the magnitude of the magnetic field B, but it would incorrectly give the electric field at ∂ B / ∂ t ≠ 0. To eliminate this shortcoming, an additional block of calculations in the toroidal geometry is needed. Here, the problem is solved analytically. The resulting final expression with ψ b well-defined in the toroidal configuration also includes the effects of the Shafranov's shift and inhomogeneity of j ζ. The proposed extensions allow generalization of the earlier results to a wider area and cover such events as CQ or VDE.
Computational and experimental studies of wave–structure interaction: Wave attenuation by a floating breakwater
Authors: Peng N. N. , Lau W. K. , Wai O. W. H. , Chow K. W.
Published: April 2023

Interactions between surface gravity waves and a floating rigid body are complex, as waves may reflect from, break on, and be transmitted behind the body. Studies of these phenomena are critically important in improving the safety and functional efficiency of offshore structures. Here, the wave attenuation performance and motions of a type of floating breakwater (FB) are studied through numerical and experimental approaches. A numerical wave tank (NWT) is developed based on the software OpenFOAM and properties of wave channel from a laboratory. In the NWT, the air–water interface is captured by the volume of fluid method. The motions of FB are tracked by the six degrees of freedom model. A mooring system model is developed to simulate the constraints of the FB. Large eddy simulation turbulence modeling is implemented for the wave breaking processes. A model FB with a scale of 1:20 is tested in both the experimental and numerical wave channel. Wave heights at the back/front of the FB and the constraint forces of the mooring wires are measured. The numerical models are validated by comparing the results with experimental measurements. The variations of transmission/reflection coefficients, energy dissipation rate, and maximum mooring force are calculated. Changes of the response amplitude operators with the ratio of FB width to wavelength ( B / L w) and wave steepness are analyzed. The wave transmission coefficient will drop below 0.8 if the value of B / L w is larger than 0.3, but will go over 0.95 if B / L w is less than 0.1. Wave steepness has a large influence on FB motions and the mooring system. The effect of Stokes drift is observed by the shift of position of the FB.
Analysis of structural disorder on Raman spectra of semiconductors
Authors: Rambadey Omkar V. , Gupta Minal , Kumar Anil , Sagdeo Pankaj R.
Published: April 2023

This Tutorial provides a fundamental discussion on the lattice dynamics of physical systems introduced with disorder and, hence, the importance of Raman spectroscopy (RS) technique to probe these impacts. The article first discusses, analytically, the impact of disorder on the symmetry allowed phonon modes of the system by considering the finite probability of discrete-continuum interference in terms of electron–phonon interactions in the system, thereby briefly discussing the relevant experimental reports, followed by providing an ephemeral description on the loss of translational symmetry in the lattice environment under the strain field generated due to disorder and its consequence as relaxation of the q→=0 selection rule in terms of RS; thus, correlating these discussions with the observation of the symmetry-forbidden disorder induced phonon modes. The same is also elaborated with the experimental reports on various systems of ABO3 and AO2 kinds, where A and B are cations that exhibit the occurrence of disorder induced phonon modes in the respective Raman spectra because of the disorder introduced into the host lattice, and which is emphasized to be not originating due to any structural phase transitions.
Tctp, a unique Ing5-binding partner, inhibits the chromatin binding of Enok in
Drosophila
Authors: Kim Lee-Hyang , Kim Ja-Young , Xu Yu-Ying , Lim Mi Ae , Koo Bon Seok , Kim Jung Hae , Yoon Sung-Eun , Kim Young-Joon , Choi Kwang-Wook , Chang Jae Won , Hong Sung-Tae
Published: April 2023

The MOZ/MORF histone acetyltransferase complex is highly conserved in eukaryotes and controls transcription, development, and tumorigenesis. However, little is known about how its chromatin localization is regulated. Inhibitor of growth 5 (ING5) tumor suppressor is a subunit of the MOZ/MORF complex. Nevertheless, the in vivo function of ING5 remains unclear. Here, we report an antagonistic interaction between
Drosophila
Translationally controlled tumor protein (TCTP) (Tctp) and ING5 (Ing5) required for chromatin localization of the MOZ/MORF (Enok) complex and H3K23 acetylation. Yeast two-hybrid screening using Tctp identified Ing5 as a unique binding partner. In vivo, Ing5 controlled differentiation and down-regulated epidermal growth factor receptor signaling, whereas it is required in the Yorkie (Yki) pathway to determine organ size.
Ing5
and
Enok
mutants promoted tumor-like tissue overgrowth when combined with uncontrolled Yki activity. Tctp depletion rescued the abnormal phenotypes of the
Ing5
mutation and increased the nuclear translocation of Ing5 and chromatin binding of Enok. Nonfunctional Enok promoted the nuclear translocation of Ing5 by reducing Tctp, indicating a feedback mechanism between Tctp, Ing5, and Enok to regulate histone acetylation. Therefore, Tctp is essential for H3K23 acetylation by controlling the nuclear translocation of Ing5 and chromatin localization of Enok, providing insights into the roles of human TCTP and ING5-MOZ/MORF in tumorigenesis.
Shigella
IpaH9.8 limits GBP1-dependent LPS release from intracytosolic bacteria to suppress caspase-4 activation
Authors: Goers Lisa , Kim Kyungsub , Stedman Teagan C. , Canning Patrick J. , Mou Xiangyu , Ernst Nadja Heinz , Coers Jörn , Lesser Cammie F.
Published: April 2023

Pyroptosis is an inflammatory form of cell death induced upon recognition of invading microbes. During an infection, pyroptosis is enhanced in interferon-gamma-exposed cells via the actions of members of the guanylate-binding protein (GBP) family. GBPs promote caspase-4 (CASP4) activation by enhancing its interactions with lipopolysaccharide (LPS), a component of the outer envelope of Gram-negative bacteria. Once activated, CASP4 promotes the formation of noncanonical inflammasomes, signaling platforms that mediate pyroptosis. To establish an infection, intracellular bacterial pathogens, like
Shigella
species, inhibit pyroptosis. The pathogenesis of
Shigella
is dependent on its type III secretion system, which injects ~30 effector proteins into host cells. Upon entry into host cells,
Shigella
are encapsulated by GBP1, followed by GBP2, GBP3, GBP4, and in some cases, CASP4. It has been proposed that the recruitment of CASP4 to bacteria leads to its activation. Here, we demonstrate that two
Shigella
effectors, OspC3 and IpaH9.8, cooperate to inhibit CASP4-mediated pyroptosis. We show that in the absence of OspC3, an inhibitor of CASP4, IpaH9.8 inhibits pyroptosis via its known degradation of GBPs. We find that, while some LPS is present within the host cell cytosol of epithelial cells infected with wild-type
Shigella,
in the absence of IpaH9.8, increased amounts are shed in a GBP1-dependent manner. Furthermore, we find that additional IpaH9.8 targets, likely GBPs, promote CASP4 activation, even in the absence of GBP1. These observations suggest that by boosting LPS release, GBP1 provides CASP4-enhanced access to cytosolic LPS, thus promoting host cell death via pyroptosis.
Heterozygosity for cervid S138N polymorphism results in subclinical CWD in gene-targeted mice and progressive inhibition of prion conversion
Authors: Arifin Maria I. , Kaczmarczyk Lech , Zeng Doris , Hannaoui Samia , Lee Chi , Chang Sheng Chun , Mitchell Gordon , McKenzie Debbie , Beekes Michael , Jackson Walker , Gilch Sabine
Published: April 2023

Prions are proteinaceous infectious particles that replicate by structural conversion of the host-encoded cellular prion protein (PrP
C
), causing fatal neurodegenerative diseases in mammals. Species-specific amino acid substitutions (AAS) arising from single nucleotide polymorphisms within the prion protein gene (
Prnp
) modulate prion disease pathogenesis, and, in several instances, reduce susceptibility of homo- or heterozygous AAS carriers to prion infection. However, a mechanistic understanding of their protective effects against clinical disease is missing. We generated gene-targeted mouse infection models of chronic wasting disease (CWD), a highly contagious prion disease of cervids. These mice express wild-type deer or PrP
C
harboring the S138N substitution homo- or heterozygously, a polymorphism found exclusively in reindeer (
Rangifer tarandus spp.
) and fallow deer (
Dama dama
). The wild-type deer PrP-expressing model recapitulated CWD pathogenesis including fecal shedding. Encoding at least one 138N allele prevented clinical CWD, accumulation of protease-resistant PrP (PrP
res
) and abnormal PrP deposits in the brain tissue. However, prion seeding activity was detected in spleens, brains, and feces of these mice, suggesting subclinical infection accompanied by prion shedding. 138N-PrP
C
was less efficiently converted to PrP
res
in vitro than wild-type deer (138SS) PrP
C
. Heterozygous coexpression of wild-type deer and 138N-PrP
C
resulted in dominant-negative inhibition and progressively diminished prion conversion over serial rounds of protein misfolding cyclic amplification. Our study indicates that heterozygosity at a polymorphic
Prnp
codon can confer the highest protection against clinical CWD and highlights the potential role of subclinical carriers in CWD transmission.
“I hope this is your last sorrow”
Authors: Sheikhan Amir
Published: April 2023

The objective of the present study is to examine condolence strategies and the sociocultural norms underlying the realisation of the speech act of condolence in Persian. To achieve this, a three-layered data collection methodology including two focus group interviews (FGIs), field notes, and a discourse completion task (DCT) were used. FGIs and field notes were utilised to shed light on the cultural norms as well as any variables affecting the expressions of condolence. The DCT, on the other hand, was administered to explicate the form and frequency of condolence strategies in Persian. Results indicate that, influenced by six sociocultural variables, 20 distinct condolence strategies are used in Persian. Furthermore, findings show that, while these strategies are used with varying degrees of frequency in different situations, when expressing condolence, Persian speakers place high importance on empathising with the bereaved interlocutor.
Superimposition of topological charges between vortex beams and singular points of photonic crystal slabs
Authors: Gao Wenya , Liu Ziyi , Li Xiangning , Wang Xu , Hu Guanqu , Ye Weimin , Guan Chunying , Liu Jianlong
Published: April 2023

The bound state in the continuum (BIC) is a singular point of polarization in the momentum space of a periodic structure. It has been demonstrated that vortex beams can be generated by utilizing the polarization vortex around BIC based on the geometric phase in momentum space. In this letter, we propose a reflective photonic crystal (PhC) to generate a vortex beam and demonstrate the superimposition of topological charges in the momentum space between PhC and the vortex beams. In addition to BICs, we demonstrate that other singularities like degenerate points can also be used to generate vortex beams.
Dynamic characteristics and crack evolution laws of coal and rock under split Hopkinson pressure bar impact loading
Authors: Sun Xiaoyuan , Jin Tingxu , Li Jihui , Xie Jianlin , Li Chuantian , Li Xiaoxia
Published: April 2023

The dynamic mechanical properties and crack evolution characteristics of coal and rock during split Hopkinson pressure bar (SHPB) impact failure are important contents for analysis. In previous studies, the coal and rock specimens used have usually been independent and not closely correlated. In addition, quantitative characterization and analysis methods for coal and rock cracks are immature, and more information has not been fully revealed. The aims of this paper are to comprehensively explore both the dynamic mechanical properties and crack evolution characteristics of coal and rock during impact failure. First, experimental specimens are prepared from coal seam, direct roof rock strata and direct floor rock strata in the same area to highlight the correlations between test pieces. Second, a dynamic strain gauge and high-speed (HS) camera are adopted to reflect the stress wave signal and crack evolution. Then, based on digital image correlation (DIC) technology and the mass screening method, the evolution laws of surface cracks during crushing and the distribution characteristics of sample fragments after crushing are studied from the perspective of fractal, and finally compared with those of the simulation analysis. The results are as follows. (1) The coal and rock samples from the same area have both consistency and differences. The dynamic mechanical properties of coal and rock are affected by the impact velocity and the physical properties of the specimen. Higher impact speeds and densities lead to the more obvious brittleness of the specimen when destroyed. Conversely, the sample shows more plasticity and ductile yield. (2) The self-similarity is significantly manifested in the evolution of surface cracks during impact and the distribution characteristics of fragments after impact. The box dimension and quality screening dimension are applicable to quantitatively characterize the evolution process and results of coal and rock fractures. (3) The simulation results based on the Holmquist–Johnson–Cook (HJC) and Riedel–Hiermaier–Thoma (RHT) constitutive models agree well with the experimental results, and the RHT constitutive model is more consistent. This study may contribute to a more comprehensive understanding of the dynamic characteristics and crack evolution laws of coal and rock under impact loading and provide references for further research and discussion.
Friction properties of black phosphorus: a first-principles study
Authors: Wang Changqing , He Qing , Guo Peng , Qi Haoqiang , Su Jianfeng , Chen Weiguang , Tang Chunjuan , Jia Yu
Published: April 2023

Based on the first-principle, the friction anisotropy, structural super-lubricity and oxidation induced ultra-low friction of black phosphorus at atomic scale under different loads have been studied. The results show that the interface friction of black phosphorus is anisotropic, that is, the friction along the armchair direction is greater than that along the zigzag direction. Moreover, the friction between the black phosphorus interfaces shows a structural superlubricity property, and the incommensurate interface friction is approximately one thousandth of the commensurate interface friction, which is mainly due to the less electronic charge and the smaller amplitude of electronic charge change between the incommensurate interfaces during the friction process. In addition, the oxidation of black phosphorus is beneficial for lubrication between interfaces.
On the nonlinear Schrödinger equation with a toroidal-shaped trap in the strong confinement regime
Authors: Hong Younghun , Jin Sangdon
Published: April 2023

We consider the 3D cubic nonlinear Schrödinger equation (NLS) with a strong toroidal-shaped trap. In the first part, we show that as the confinement is strengthened, a large class of global solutions to the time-dependent model can be described by 1D flows solving the 1D periodic NLS (theorem 1.4). In the second part, we construct a steady state as a constrained energy minimizer, and prove its dimension reduction to the well-known 1D periodic ground state (theorems 1.6 and 1.7). Then, employing the dimension reduction limit, we establish the local uniqueness and the orbital stability of the 3D ring soliton (theorem 1.8). These results justify the emergence of stable quasi-1D periodic dynamics for Bose–Einstein condensates on a ring in physics experiments.
The death of the short-form physics essay in the coming AI revolution
Authors: Yeadon Will , Inyang Oto-Obong , Mizouri Arin , Peach Alex , Testrow Craig P
Published: April 2023

The latest AI language modules can produce original, high quality full short-form (300-word) Physics essays within seconds. These technologies such as ChatGPT and davinci-003 are freely available to anyone with an internet connection. In this work, we present evidence of AI generated short-form essays achieving First-Class grades on an essay writing assessment from an accredited, current university Physics module. The assessment requires students answer five open-ended questions with a short, 300-word essay each. Fifty AI answers were generated to create ten submissions that were independently marked by five separate markers. The AI generated submissions achieved an average mark of

71
±
2
%

, in strong agreement with the current module average of

71
±
5
%

. A typical AI submission would therefore most-likely be awarded a First Class, the highest classification available at UK universities. Plagiarism detection software returned a plagiarism score between

2
±
1

% (Grammarly) and

7
±
2

% (TurnitIn). We argue that these results indicate that current natural language processing AI represent a significant threat to the fidelity of short-form essays as an assessment method in Physics courses.