bluuebunny/crossref_metadata_2025 huggingface dataset:
Record-high Antarctic Peninsula temperatures and surface melt in February 2022: a compound event with an intense atmospheric river
Authors: Gorodetskaya Irina V. , Durán-Alarcón Claudio , González-Herrero Sergi , Clem Kyle R. , Zou Xun , Rowe Penny , Rodriguez Imazio Paola , Campos Diego , Leroy-Dos Santos Christophe , Dutrievoz Niels , Wille Jonathan D. , Chyhareva Anastasiia , Favier Vincent , Blanchet Juliette , Pohl Benjamin , Cordero Raul R. , Park Sang-Jong , Colwell Steve , Lazzara Matthew A. , Carrasco Jorge , Gulisano Adriana Maria , Krakovska Svitlana , Ralph F. Martin , Dethinne Thomas , Picard Ghislain
Published: December 2023

The Antarctic Peninsula (AP) experienced a new extreme warm event and record-high surface melt in February 2022, rivaling the recent temperature records from 2015 and 2020, and contributing to the alarming series of extreme warm events over this region showing stronger warming compared to the rest of Antarctica. Here, the drivers and impacts of the event are analyzed in detail using a range of observational and modeling data. The northern/northwestern AP was directly impacted by an intense atmospheric river (AR) attaining category 3 on the AR scale, which brought anomalous heat and rainfall, while the AR-enhanced foehn effect further warmed its northeastern side. The event was triggered by multiple large-scale atmospheric circulation patterns linking the AR formation to tropical convection anomalies and stationary Rossby waves, with an anomalous Amundsen Sea Low and a record-breaking high-pressure system east of the AP. This multivariate and spatial compound event culminated in widespread and intense surface melt across the AP. Circulation analog analysis shows that global warming played a role in the amplification and increased probability of the event. Increasing frequency of such events can undermine the stability of the AP ice shelves, with multiple local to global impacts, including acceleration of the AP ice mass loss and changes in sensitive ecosystems.
Bioinspired photocatalytic systems towards compartmentalized artificial photosynthesis
Authors: Velasco-Garcia Laura , Casadevall Carla
Published: December 2023

Artificial photosynthesis aims to produce fuels and chemicals from simple building blocks (i.e. water and carbon dioxide) using sunlight as energy source. Achieving effective photocatalytic systems necessitates a comprehensive understanding of the underlying mechanisms and factors that control the reactivity. This review underscores the growing interest in utilizing bioinspired artificial vesicles to develop compartmentalized photocatalytic systems. Herein, we summarize different scaffolds employed to develop artificial vesicles, and discuss recent examples where such systems are used to study pivotal processes of artificial photosynthesis, including light harvesting, charge transfer, and fuel production. These systems offer valuable lessons regarding the appropriate choice of membrane scaffolds, reaction partners and spatial arrangement to enhance photocatalytic activity, selectivity and efficiency. These studies highlight the pivotal role of the membrane to increase the stability of the immobilized reaction partners, generate a suitable local environment, and force proximity between electron donor and acceptor molecules (or catalysts and photosensitizers) to increase electron transfer rates. Overall, these findings pave the way for further development of bioinspired photocatalytic systems for compartmentalized artificial photosynthesis.
Dynamics and resilience of the unconventional charge density wave in ScV6Sn6 bilayer kagome metal
Authors: Tuniz Manuel , Consiglio Armando , Puntel Denny , Bigi Chiara , Enzner Stefan , Pokharel Ganesh , Orgiani Pasquale , Bronsch Wibke , Parmigiani Fulvio , Polewczyk Vincent , King Phil D. C. , Wells Justin W. , Zeljkovic Ilija , Carrara Pietro , Rossi Giorgio , Fujii Jun , Vobornik Ivana , Wilson Stephen D. , Thomale Ronny , Wehling Tim , Sangiovanni Giorgio , Panaccione Giancarlo , Cilento Federico , Di Sante Domenico , Mazzola Federico
Published: December 2023

Long-range electronic ordering descending from a metallic parent state constitutes a rich playground to study the interplay of structural and electronic degrees of freedom. In this framework, kagome metals are in the most interesting regime where both phonon and electronically mediated couplings are significant. Several of these systems undergo a charge density wave transition. However, to date, the origin and the main driving force behind this charge order is elusive. Here, we use the kagome metal ScV6Sn6as a platform to investigate this problem, since it features both a kagome-derived nested Fermi surface and van-Hove singularities near the Fermi level, and a charge-ordered phase that strongly affects its physical properties. By combining time-resolved reflectivity, first principles calculations and photo-emission experiments, we identify the structural degrees of freedom to play a fundamental role in the stabilization of charge order, indicating that ScV6Sn6features an instance of charge order predominantly originating from phonons.
Amorphous silicon intrinsic photomixing detector for optical ranging
Authors: Bablich Andreas , Müller Maurice , Bornemann Rainer , Marrenbach Nils , Kienitz Paul , Haring Bolívar Peter
Published: December 2023

Today’s optical range finders or 3D imagers suffer from significant drawbacks and do not allow to combine performance (sensitivity, precision) with simplicity, and scalability enabling very-large scale integration with minimum footprint. Here, we present the amorphous silicon Intrinsic Photomixing Detector (IPD) for direct and highly sensitive optical envelope mixing. The ability to generate a photocurrent that is proportional to the nonlinear mixing of two optical modulation envelope functions enables high performance Time-of-Flight optical ranging at low light levels down to $$\sim \!0.1\,{{{{{\rm{mW}}}}}}{{{{{\rm{cm}}}}}}^{-2}$$
~

0.1

mW

cm

−
2

at $$444\,{{{{{\rm{nm}}}}}}$$
444

nm
. The IPD exceeds MHz bandwidth, covers a broad distance detection range from $$10\,{{{{{\rm{cm}}}}}}$$
10

cm
to $$101\,{{{{{\rm{m}}}}}}$$
101

m
, and achieves a mean depth resolution below $$44\,{{{{{\rm{mm}}}}}}$$
44

mm
for distances up to $$25\,{{{{{\rm{m}}}}}}$$
25

m
. The IPD paves the way towards simple but high-performance photodetectors that allow for very-large scale integration on top of silicon or flexible electronics at low costs with pixel fill factors up to 100%.
Recent advances in optical biosensing and imaging of telomerase activity and relevant signal amplification strategies
Authors: Yang Ruining , Hu Junbo , Zhang Longsheng , Liu Xingfen , Huang Yanqin , Zhang Lei , Fan Quli
Published: December 2023

Fluorometric, colorimetry, chemiluminescence, SERS, and dual-mode techniques for biosensing and imaging of telomerase are summerized. Relevant signal amplification strategies are included to provide ideas for exploration of more practicable methods.
Metal-dependent activity control of a compact-sized 8–17 DNAzyme based on metal-mediated unnatural base pairing
Authors: Takezawa Yusuke , Hu Lingyun , Nakama Takahiro , Shionoya Mitsuhiko
Published: December 2023

A compactly-folded 8–17 DNAzyme was reshaped into a metal-responsive allosteric DNAzyme by introducing a CuII-meditated unnatural base pair.
Reply to the ‘Comment on “Perturbation theory of scattering for grazing-incidence fast-atom diffraction”’ by G. A. Bocan, H. Breiss, S. Szilasi, A. Momeni, E. M. S. Casagrande, E. A. Sánchez, M. S. Gravielle and H. Khemliche, Phys. Chem. Chem. Phys., 2023, 25, DOI: 10.1039/D3CP02486E
Authors: Allison W. , Miret-Artés S. , Pollak E.
Published: December 2023

Perturbation theory, in first order, fits experiment as well as DFT-based potentials suggesting modulation of the well-depth across the scattering channel contributes to observed changes in the rainbow angle.
ReaxFF molecular dynamics of graphene oxide/NaCl aqueous solution interfaces
Authors: Akbarzadeh Rokhsareh , Předota Milan
Published: December 2023

Structural and dynamical properties of graphene (G), graphene oxide (GO), and graphite oxide (GTO) interfaces with NaCl aqueous solution: functional groups, radial distribution functions, density profiles and diffusivities of water and ions.
Metal–organic framework-derived metal oxides for resistive gas sensing: a review
Authors: Wang Luyu , Song Jia , Yu Chunyang
Published: December 2023

This review system introduces the research progress of metal–organic framework-derived metal oxides for resistive gas sensing in recent years. The introduced metal oxides are mainly categorized into 1D, 2D, and 3D.
Solvent effects on the intramolecular charge transfer excited state of 3CzClIPN: a broadband transient absorption study
Authors: Zheng Ruofei , Cheng Meixin , Ma Ruishu , Schipper Derek , Pichugin Kostyantyn , Sciaini Germán
Published: December 2023

Broadening of intramolecular charge-transfer excited-state absorption of 3CzClIPN in aromatic solvents: a local probe of the medium's polarity.
Simulating high-pressure surface reactions with molecular beams
Authors: Taleb Amjad Al , Schiller Frederik , Vyalikh Denis V. , María Pérez José , Auras Sabine V. , Farías Daniel , Ortega J. Enrique
Published: December 2023

Using a reactive molecular beam with high kinetic energy (Ekin), it is possible to speed gas–surface reactions involving high activation barriers (Eact), which would require elevated pressures if a random gas is used.
Spiers Memorial Lecture: Lithium air batteries – tracking function and failure
Authors: Fritzke Jana B. , Ellison James H. J. , Brazel Laurence , Horwitz Gabriela , Menkin Svetlana , Grey Clare P.
Published: December 2023

Here, we discuss experimental approaches developed by some of the authors to understand the function and failure of lithium–oxygen batteries.
Direct air-induced arylphosphinoyl radicals for the synthesis of benzo[b]phosphole oxides
Authors: Huang Mingqing , Huang Haiyang , You Mengyao , Zhang Xinxin , Sun Longgen , Chen Chao , Mei Zhichao , Yang Ruchun , Xiao Qiang
Published: December 2023

The direct air-oxidation strategy enables the transformation of arylphosphine oxides into phosphinoyl radicals, which are subsequently used in the synthesis of benzo[b]phosphole oxides by combining with various alkynes.
Unexpected stereoselective CuBr2-catalyzed cascade reaction of 2-ethynylanilines with silylynamides: facile and atom-economical access to N-vinylsilylindoles
Authors: Li Zengzeng , Lu Fei , Xu Qingchun , Liu Gang , Zhao Ximei , Wang Guanghui
Published: December 2023

A stereoselective, ligand-free, and cost-effective CuBr2-catalyzed cascade reaction of 2-ethynylanilines with silylynamides toward valuable N-vinylsilylindoles is developed under air conditions.
Highly efficient, catalyst-free, one-pot sequential four-component synthesis of novel spiroindolinone-pyrazole scaffolds as anti-Alzheimer agents: in silico study and biological screening
Authors: Pourtaher Hormoz , Mohammadi Yasaman , Hasaninejad Alireza , Iraji Aida
Published: December 2023

Alzheimer's disease is a neurodegenerative disorder that impacts memory, thinking, and behavior, and currently, there is no effective cure available for its treatment.
Heterobimetallic iridiumIII–europiumIII complex: the role of donor energy on sensitising the EuIII ion
Authors: Canisares Felipe da Silva Manrique , Silva Renan Caike , Davolos Marian Rosaly , Pires Ana Maria , Lima Sergio Antonio Marques
Published: December 2023

The lowest triplet energy from an IrIII complex that efficiently sensitises EuIII ion in an IrIII–EuIII heterobimetallic complex was determined.
Reusable magnetic graphene oxide based anion exchanger for the separation and removal of anionic dyes
Authors: Kumari Poonam , Disha  , Rani Raj , Patel Manoj K. , Mishra Sunita , Singhai Sandeep , Nayak Manoj K.
Published: December 2023

Eco-friendly and reusable graphene-based magnetic anion exchange (NMGO) adsorption–desorption mechanisms and the most promising for the effective removal of anionic Congo red dyes from environmental samples.
Bacterial cyclophane-containing RiPPs from radical SAM enzymes
Authors: Phan Chin-Soon , Morinaka Brandon I.
Published: December 2023

This report highlights recent reports of bacteria-derived cyclophane-containing peptides from radical SAM/SPASM enzymes. The strategies for discovery, structures of the products, bioactivity, mechanism of formation, and synthesis are discussed.
A novel synthetic method for backbone-cyclized polypeptide POL7080 with the help of hydrophobic-support materials
Authors: Gu Xiaotong , Chen Weijin , Guo Ting , Chang Xiaohong , Zhang Shenyan , Bai Bingfang , Ma Shutao
Published: December 2023

This is a simple, effective and low-cost liquid-phase synthesis route suitable for large-scale production of POL7080, a cyclized polypeptide.
Pyrene-bridged acenaphthenes: synthesis and properties of a diacenaphtho[1,2-e:1′,2′-l]pyrene and its symmetrical nitrogen analogue
Authors: Polkaehn Jonas , Ehlers Peter , Villinger Alexander , Langer Peter
Published: December 2023

Pyrene-bridged acenaphthenes were prepared and their optical and electronic properties were studied by experimental and computational methods.
Graphitic carbon nitride (g-C3N4) as an emerging photocatalyst for sustainable environmental applications: a comprehensive review
Authors: Bhanderi Dhavalkumar , Lakhani Pratikkumar , Modi Chetan K.
Published: December 2023

g-C3N4: a sustainable game-changer in photocatalysis. This work explores synthesis, properties, mechanisms, and applications, addresses challenges, and charts future trends.
Sustainability-driven photocatalysis: oxygen-doped g-C3N4 for organic contaminant degradation
Authors: Mishra Soumya Ranjan , Gadore Vishal , Ahmaruzzaman Md.
Published: December 2023

The unique characteristics of oxygen-doped g-C3N4 (O@g-C3N4), including enhanced charge carrier mobility and changed electronic structure, make it especially appealing for photocatalytic applications.
Microwave-assisted valorization of biodiesel byproduct glycerol to solketal over Musa acuminata peel waste derived solid acid catalyst: process optimization, kinetics, and thermodynamics
Authors: Devasan Rhithuparna , Gouda Shiva Prasad , Halder Gopinath , Rokhum Samuel Lalthazuala
Published: December 2023

The massive quantity of glycerol produced due to the rapid expansion of biodiesel production requires its transformation into value-added products utilizing novel and sustainable methods.
Strategies to improve the mechanical robustness of metal halide perovskite solar cells
Authors: Li Muzhi , Johnson Samuel , Gil-Escrig Lidon , Sohmer Maayan , Figueroa Morales Carlos A. , Kim Hongki , Sidhik Siraj , Mohite Aditya , Gong Xiwen , Etgar Lioz , Bolink Henk J. , Palmstrom Axel , McGehee Michael D. , Rolston Nicholas
Published: December 2023

We demonstrate the fragility of perovskite solar cells is typically in the small molecule electron transport layer and show strategies for designing more mechanically and operationally robust devices by improving the layers and interfaces.
Three-dimensional N, P, and O tri-doped porous carbon for multifunctional electrocatalytic reactions
Authors: Chen Lulu , Zhang Yanan , Liu Zhihui , Hou Liqiang , Liu Xien
Published: December 2023

Multifunctional tridoped porous carbon electrocatalysts for simultaneous oxygen reduction, oxygen evolution, and hydrogen evolution.
Reading for Meaning: The Influence of Reader Characteristics on Paragraph Understanding in Aphasia
Authors: Webster Janet , Morris Julie , Salis Christos , Howard David
Published: December 2023

Purpose:

The study improves our understanding of the reading comprehension difficulties seen in people with aphasia. It investigates the influence of reader characteristics, including personal demographic variables, and linguistic and wider cognitive skills, on text comprehension.

Method:

Seventy-five people with aphasia and 87 neurologically typical readers completed a test of paragraph comprehension. People with aphasia also completed background tests of language, attention, recognition memory, and executive functions. The influence of demographic variables (age, gender, and level of education) was analyzed separately in the group of people with aphasia and the typical readers using analyses of variance. In the people with aphasia, the relationship between paragraph comprehension and the language and cognitive tests was explored using correlational analyses.

Results:

In the typical readers, there was a significant effect of gender and level of education and a significant three-way interaction. For the people with aphasia, there were no significant effects of demographic variables. Significant positive correlations were found between performance on paragraph comprehension and each of the language tests and with tests of auditory attention, executive functions, and recognition memory for words.

Conclusions:

In people with aphasia, the effects of demographic variables were overshadowed by the effect of their language difficulties. The association seen across language measures reflects the shared semantic representations across single-word, sentence, and text levels, across modalities. The study emphasizes the importance of attention, executive functions, and short-term memory in the comprehension of and memory for what we read. The contribution of both language difficulties and wider cognitive skills needs to be considered when planning intervention.

Supplemental Material:

https://doi.org/10.23641/asha.24695451
Detecting stellar activity cycles in p-mode travel times
Authors: Vasilyev V. , Gizon L.
Published: December 2023

Context. The 11 yr solar cycle is known to affect the global modes of solar acoustic oscillations. In particular, p mode frequencies increase with solar activity.

Aims. We propose a new method to detect the solar cycle from the p-mode autocorrelation function, and we validate this method using VIRGO/SPM photometric time series from solar cycles 23 and 24.

Methods. The p-mode autocorrelation function shows multiple wavepackets separated by time lags of ∼123 min. Using a one-parameter fitting method (from local helioseismology), we measure the seismic travel times from each wavepacket up to skip number 40.

Results. We find that the travel-time variations due to the solar cycle strongly depend on the skip number, with the strongest signature in odd skips from 17 to 31. Taking the noise covariance into account, the travel-time perturbations can be averaged over all skip numbers to enhance the signal-to-noise ratio.

Conclusions. This method is robust to noise, simpler to implement than peak bagging in the frequency domain, and is promising for asteroseismology. We estimate that the activity cycle of a Sun-like star should be detectable with this new method in Kepler-like observations down to a visual magnitude of mK ∼ 11. However, for fainter stars, activity cycles are easier to detect in the photometric variability on rotational timescales.
Feeding and feedback processes in the Spiderweb proto-intracluster medium
Authors: Lepore M. , Di Mascolo L. , Tozzi P. , Churazov E. , Mroczkowski T. , Borgani S. , Carilli C. , Gaspari M. , Ginolfi M. , Liu A. , Pentericci L. , Rasia E. , Rosati P. , Röttgering H. J. A. , Anderson C. S. , Dannerbauer H. , Miley G. , Norman C.
Published: December 2023

Context. We present a detailed analysis of the thermal, diffuse emission of the proto-intracluster medium (proto-ICM) detected in the halo of the Spiderweb Galaxy at z = 2.16, within a radius of ∼150 kpc.

Aims. Our main goal is to derive the thermodynamic profiles of the proto-ICM, establish the potential presence of a cool core and constrain the classical mass deposition rate (MDR) that may feed the nuclear and the star formation (SF) activity, and estimate the available energy budget of the ongoing feedback process.

Methods. We combined deep X-ray data from Chandra and millimeter observations of the Sunyaev–Zeldovich (SZ) effect obtained by the Atacama Large Millimeter/submillimeter Array (ALMA).

Results. Thanks to independent measurements of the pressure profile from the ALMA SZ observation and the electron density profile from the available X-ray data, we derived, for the first time, the temperature profile in the ICM of a z >  2 protocluster. It reveals the presence of a strong cool core (comparable to local ones) that may host a significant mass deposition flow, consistent with the measured local SF values. We also find mild evidence of an asymmetry in the X-ray surface brightness distribution, which may be tentatively associated with a cavity carved into the proto-ICM by the radio jets. In this case, the estimated average feedback power would be in excess of ∼1043 erg s−1. Alternatively, the asymmetry may be due to the young dynamical status of the halo.

Conclusions. The cooling time of baryons in the core of the Spiderweb protocluster is estimated to be ∼0.1 Gyr, implying that the baryon cycle in the first stages of protocluster formation is characterized by a high-duty cycle and a very active environment. In the case of the Spiderweb protocluster, we are witnessing the presence of a strongly peaked core that is possibly hosting a cooling flow with a MDR up to 250–1000 M⊙ yr−1, responsible for feeding both the central supermassive black hole (SMBH) and the high star formation rate (SFR) observed in the Spiderweb Galaxy. This phase is expected to be rapidly followed by active galactic nucleus (AGN) feedback events, whose onset may have already left an imprint in the radio and X-ray appearance of the Spiderweb protocluster, eventually driving the ICM into a self-regulated, long-term evolution in less than one Gyr.
The hydrostatic-to-lensing mass bias from resolved X-ray and optical-IR data
Authors: Muñoz-Echeverría M. , Macías-Pérez J. F. , Pratt G. W. , Pointecouteau E. , Bartalucci I. , De Petris M. , Ferragamo A. , Hanser C. , Kéruzoré F. , Mayet F. , Moyer-Anin A. , Paliwal A. , Perotto L. , Yepes G.
Published: December 2023

An accurate reconstruction of galaxy cluster masses is key to use this population of objects as a cosmological probe. In this work we present a study on the hydrostatic-to-lensing mass scaling relation for a sample of 53 clusters whose masses were reconstructed homogeneously in a redshift range between z = 0.05 and 1.07. The M500 mass for each cluster was indeed inferred from the mass profiles extracted from the X-ray and lensing data, without using a priori observable-mass scaling relations. We assessed the systematic dispersion of the masses estimated with our reference analyses with respect to other published mass estimates. Accounting for this systematic scatter does not change our main results, but enables the propagation of the uncertainties related to the mass reconstruction method or used dataset. Our analysis gives a hydrostatic-to-lensing mass bias of (1−b) = 0.739−0.070+0.075 and no evidence of evolution with redshift. These results are robust against possible subsample differences.
Examining the nature of the ultraluminous X-ray source Holmberg II X-1
Authors: Barra F. , Pinto C. , Middleton M. , Di Salvo T. , Walton D. J. , Gúrpide A. , Roberts T. P.
Published: December 2023

We present a comprehensive spectral analysis of the ultraluminous X-ray source Holmberg II X-1 using broadband and high-resolution X-ray spectra taken with the XMM-Newton satellite over a period of 19 yr, taking advantage of data from a recent campaign. We tested several models for the broadband spectra, including a double thermal component provided a reasonable description for the continuum between 0.3 and 10 keV and enabled us to constrain the properties of the accretion disc. The luminosity–temperature trends of the inner and outer disc components broadly agree with the expectations for a thin disc, although the exact values of the slopes are slightly sensitive to the adopted model. However, all tested models show L − T trends that deviate from a power law above a bolometric luminosity of about 5 × 1039 erg s−1, particularly for the hot thermal component associated with the inner accretion flow. Assuming that such deviations are due to the accretion rate exceeding its Eddington limit or, most likely, the super-critical rate, a compact object with a mass of 16–36 M⊙ was inferred, specifically, a stellar-mass black hole. The time-averaged (2021) high-resolution spectra present narrow emission lines at 1 keV primarily from Ne IX-X and a very strong at 0.5 keV from N VII, which indicate Ne–N-rich gas with non-solar abundances. This favours a nitrogen-rich donor star, such as a blue or red supergiant, which has escaped from its native stellar cluster characterised by a low-metallicity environment.
Identification des propriétés élastoplastiques des films minces de CrN en utilisant la technique de nanoindentation et la modélisation par éléments finis (FEM)
Authors: Jellad Asma
Published: December 2023

Dans ce travail, les propriétés élastoplastiques intrinsèques des films minces telles que le module d’Young E, la limite d’élasticité σy et le coefficient d’écrouissage n ont été identifiées à partir des méthodes numériques qui se basent sur des analyses dimensionnelles, des calculs par éléments finis et la résolution des algorithmes d’analyse inverse. Quatre méthodes de la littérature ont été sélectionnées pour identifier les propriétés des films minces en considérant les effets liés au substrat. De plus, l’efficacité de ces modèles numériques a été discutée à l’aide d’une vérification numérique en comparant les résultats d’identification aux propriétés introduites dans les simulations. Les propriétés mécaniques des films minces de CrN ont été enfin identifiées à l’aide de ces modèles. Les résultats d’identification ont été comparés aux propriétés mécaniques des films CrN reportées de la littérature et le bon accord montre que trois de ces quatre méthodes numériques peuvent être appliquées dans le cas des films minces.
On domination and 2-degree-packing numbers in graphs
Authors: Vázquez-Ávila Adrián
Published: December 2023

A dominating set of a graph G is a set D ⊆ V (G) such that every vertex of G is either in D or is adjacent to a vertex in D. The domination number of G, γ(G), is the minimum order of a dominating set. The domination number has become an interesting research study on several kinds of graphs, and there are many papers related to this parameter and several variants of it. In this paper, we prove that any simple graph G with no isolated vertices satisfies γ(G) ≤ ν2(G) − 1, where ν2(G) is the maximum order of a subset R of edges of G such that any three edges from R do not have the same incident vertex. This new parameter is called the 2-degree-packing of G and it is studied in a more general context but with a different name as 2-packing number, see Araujo-Pardo et al. [Util. Math. 105 (2017) 317–336]. Also, in this paper, we give a characterization of simple connected graphs G satisfying γ(G) = ν2(G) − 1.
Liebe Leserinnen und Leser …
Authors: Schmidt Karlheinz
Published: December 2023

Mikrobiom versus Makrobiom

Mit diesem Heft unserer „Ernährung & Medizin“ haben
wir dem Thema Mikrobiom, das ja derzeit hohe wissenschaftliche, aber auch
öffentliche Aufmerksamkeit genießt, einen gewissen Schwerpunkt
gewidmet. Mit dem Begriff Mikrobiom bezeichnet man die Vielzahl der Mikroorganismen,
die einerseits den Ursprung des Lebens und andererseits die
zahlenmäßig größte Biomasse auf der Erde
repräsentieren. Mikroorganismen sind ubiquitär, sodass wir
Mikrobiome im Boden, in den Weltmeeren, in der Atmosphäre, ja sogar unter
dem kilometerdicken grönländischen Eisschild oder in kochenden
Thermalquellen vorfinden.
Validierung und Reliabilitätsprüfung des „Athlete Fear Avoidance Questionnaire (AFAQ)“
Authors: Giangreco Salvatore , Benz Thomas , Luomajoki Hannu , Felsch Quinten
Published: December 2023

Hintergrund Verletzungen im Sport können für die Karriere eines Athleten schwerwiegende Folgen haben. Psychologische Faktoren spielen auf dem Weg von der Verletzung zum Wiedereinstieg in den kompetitiven Sport eine wichtige Rolle. Diese Faktoren werden oft ungenügend beurteilt, wodurch sich die Ausfallszeit verlängern kann. Mit dem Athlete Fear Avoidance Questionnaire (AFAQ) kann das Angstvermeidungsverhalten bei verletzten Athleten gemessen werden. Zum jetzigen Zeitpunkt gibt es noch keine deutsche validierte Version des Fragebogens.

Ziel Das Ziel dieser Studie ist, die Test-Retest-Reliabilität, die interne Konsistenz sowie die Konstruktvalidität der transkulturell übersetzten deutschen Version des AFAQ (AFAQ_D) bei verletzen Athletinnen und Athleten zu untersuchen.

Methode Die deutsche Version des AFAQ_D wurde mit dem TRAPD-Model übersetzt. Die Konstruktvalidität wurde mit Korrelationen zum Fear Avoidance Beliefs Questionnaire (FABQ) und zur Tampa Scale for Kinesiophobia (TSK) untersucht. Die interne Konsistenz wurde mittels Cronbach’s Alpha und die Test-Retest-Reliabilität mit dem Interklassen-Koeffizienten berechnet.

Ergebnisse Es wurden 64 Athletinnen und Athleten im Alter zwischen 16 und 36 Jahren (Ø 23,15 Jahre, ♀ 17%, ♂ 83%) nach verschiedenen Verletzungen eingeschlossen. Der AFAQ_D ergab gute Werte in der Reliabilität mit einem Cronbach’s Alpha von 0,76 (95%CI; 0,67–0,84) bei der ersten beziehungsweise 0,82 (95%CI; 0,76–0,88) bei der zweiten Messung und einem Interklassen-Koeffizienten von 0,798 (95%CI; 0,674–0,876). Die Validität ergab eine moderate Korrelation zwischen dem AFAQ_D und der TSK (r= 0,57, p<0.01) und eine schwache und nicht signifikante Korrelation zwischen dem AFAQ_D und dem FABQ (r = 0,13, p=0.31).

Schlussfolgerung Die deutsche Version vom AFAQ ist größtenteils ein valider und reliabler Fragebogen zur Beurteilung der Angstvermeidung, als auch der psychologischen Bereitschaft von Athletinnen und Athleten nach einer Verletzung. Die Korrelationen mit TSK und FABQ sind grob mit der Originalstudie vergleichbar.
Präanalytik biochemischer
Knochenumsatzparameter
Authors: Fassbender Walter , Willmann Birgit
Published: December 2023

Die Präanalytik umfasst alle technischen und organisatorischen
Abläufe der Gewinnung und Lagerung von Proben, wie Blut oder Urin, und
deren sachgerechten Transport in ein für die gewünschte
Untersuchung geeignetes Labor. Ihr Stellenwert wird besonders dadurch
hervorgehoben, dass aktuell ein nicht unerheblicher Teil inkorrekter Laborwerte
auf Fehler in den präanalytischen Abläufen und nicht auf Fehler
im Labor zurückzuführen sind. Auch Knochenumsatzparameter, die
zur Beurteilung der Dynamik des Knochenstoffwechsels und dem Monitoring
metabolischer Knochenerkrankungen dienen, unterliegen, wie viele andere
Parameter auch, nicht nur patientenabhängigen Faktoren, sondern auch
Einflussgrößen wie beispielsweise Gabe von Medikamenten,
Variabilität von Tag zu Tag, saisonaler, interindividueller oder
intraindividueller Variation und einer zirkadianen Rhythmik. Die
Zuverlässigkeit und Vergleichbarkeit von Laborwerten lässt sich
also durch das Einhalten standardisierter präanalytischer
Abläufe entscheidend beeinflussen.
18F-Fluorocholine PET-CT Outshines Sestamibi Scintigraphy in Detecting Parathyroid Adenomas in the Background of Hashimoto's Thyroiditis
Authors: Chandra Piyush , Nandy Dipayan , Saini Samir
Published: December 2023

Ultrasonography neck and dual-phase 99mTc-sestamibi (MIBI) scan are standard imaging techniques for the detection of parathyroid adenomas in primary hyperparathyroidism. However, in presence of coexistent thyroid disease or small size of adenomas, the accuracy of these imaging modalities is low and leads to delayed diagnosis. We here present a report of two patients with primary hyperparathyroidism and with a nondiagnostic MIBI scan, who subsequently underwent successful surgery after positive localization of adenomas on 18F-fluorocholine positron emission tomography-computed tomography.
Backward fast electrons supported by ionization wave passing through the grid cathode
Authors: Babaeva N. Yu. , Naidis G. V. , Tereshonok D. V. , Tarasenko V. F. , Zhang Ch. , Shao Tao
Published: December 2023

In this paper, the effect of appearance of fast electrons behind the grid cathode in the direction reverse to the anode is studied computationally. Fast electrons are observed within 0.5 ns after application of a short voltage pulse. The results obtained confirm the possibility of generation of backward fast electrons (some of them are in a runaway mode) and explain the main trends of this process. It is shown that backward fast electrons are supported by the ionization wave (IW). The IW evolution proceeds via two phases. During the first phase, first fast electrons are observed moving toward the anode. Then, multiple individual IWs starting from each individual cathode wire are formed in the anode–cathode gap. The duration of this stage is 0.3 ns and corresponds to the pulse rise time. At the second phase, the separate individual IWs merge in a single flat ionization wave. The IW penetrates through the cathode wires and propagates in the direction reverse to the anode. The preferred direction of fast electrons propagation also reverses. Now, the trajectories of fast electrons are mainly directed away from the anode. The duration of the recorded flux of fast electrons is of the order of a few picoseconds. This time interval correlates with the available experimental data.
Scalable ferroelectricity of 20 nm-thick (Al0.8Sc0.2)N thin films sandwiched between TiN electrodes
Authors: Ota Reika , Yasuoka Shinnosuke , Mizutani Ryoichi , Shiraishi Takahisa , Okamoto Kazuki , Kakushima Kuniyuki , Koganezawa Tomoyuki , Sakata Osami , Funakubo Hiroshi
Published: December 2023

Ferroelectric (Al, Sc)N thin films have the potential for use in low-power memory applications. This study demonstrates the thickness scalability of ferroelectricity down to an approximately 20 nm-thick (Al0.8Sc0.2)N film sandwiched between microfabricable TiN electrodes. The impact of the deposition gas atmosphere during the sputtering process and the top electrode materials on the crystal structures and ferroelectric properties was investigated for 20–30 nm-thick (Al0.8Sc0.2)N thin films deposited on Si substrates covered with a TiN layer by radio frequency magnetron sputtering. The deposition atmosphere did not strongly affect the crystal structures of the 30 nm-thick (Al0.8Sc0.2)N films but significantly affected their ferroelectric properties. The leakage current density decreased for films deposited under pure N2 gas compared to the films deposited under a gas mixture of 0.67Ar + 0.33N2. The ferroelectric properties of 20 nm-thick (Al0.8Sc0.2)N films were changed by the top electrode materials; both the switching electric field and its maximum applicable electric field increased for the TiN top electrodes compared with the Pt top electrodes, improving the saturation characteristics of the remnant polarization (Pr) against the applied electric field. Consequently, the 20 nm-thick (Al0.8Sc0.2)N film sandwiched between the microfabricable TiN top and bottom electrodes showed ferroelectricity without noticeable degradation with decreasing film thickness; the film maintained large Pr values of over 100 μC/cm2 in the temperature range from room temperature to 150 °C. The present data open the door to scalable ferroelectric random-access memories using almost thickness-degradation-free thin (Al, Sc)N films with microfabricable TiN electrodes.
Non-uniformity of the radial electric field for tokamak plasma on the low and the high toroidal magnetic field side
Authors: Romannikov Alexander , Khvostenko Peter
Published: December 2023

This paper presents a relativistic mechanism that can create a non-uniformity of a radial electric field on the low side and the high toroidal magnetic field side of tokamak plasmas. This mechanism is associated with the significant current velocity of electrons in the plasma for many experimental modes of tokamak operation. It is important that electric fields arise without the separation of charges in the plasma. The traditional approach to determining radial electric fields in tokamak plasmas gives a uniform radial electric field on magnetic surfaces inside the plasma, while there are no radial electric fields outside the plasma. The presented mechanism leads to the appearance of an electric field outside the plasma with a current, and a non-uniformity of the radial electric field on magnetic surfaces appears inside the plasma. The proposed mechanism can explain the experimentally measured non-uniformity of C+6 carbon ion toroidal rotation velocities in the Tore-Supra tokamak plasma.
Proton radiation hardness and its loss mechanism of Cu2ZnSn(S,Se)4 thin film solar cells
Authors: Zhao Yun , Zheng Shiyu , Zhao Yuming , Luo Zhengjun , Li Yumo , Wu Yongkang , Chen Jiangtao , Chen Jianbiao , Zhang Xuqiang , Chai Liqiang , Han Xiuxun , Xin Hao , Li Yan
Published: December 2023

Kesterite Cu2ZnSn(S,Se)4 (CZTSSe) have proven to be promising materials for photovoltaic applications. The current state-of-the-art CZTSSe photovoltaic device improvements in efficiency have been hampered by difficulties in increasing open circuit voltages (VOC). Herein, we thoroughly analyzed the proton irradiation hardness and its loss mechanism of CZTSSe thin film solar cells. The efficiency loss mechanism of the CZTSSe solar cell is proposed by systematically studying the device performance, optical and electrical properties, and distribution changes in elements upon proton irradiation. It was revealed that proton-irradiation-induced element diffusion in device affects the absorber properties and CdS/CZTSSe heterojunction dramatically and deteriorates the performance of the device. Finally, the main factors that may affect device performance of CZTSSe solar cells are highlighted, and the CZTSSe solar cells also demonstrate a remarkable radiation hardness.
A method to generate perfusable physiologic-like vascular channels within a liver-on-chip model
Authors: Ferrari E. , Monti E. , Cerutti C. , Visone R. , Occhetta P. , Griffith L. G. , Rasponi M.
Published: December 2023

The human vasculature is essential in organs and tissues for the transport of nutrients, metabolic waste products, and the maintenance of homeostasis. The integration of vessels in in vitro organs-on-chip may, therefore, improve the similarity to the native organ microenvironment, ensuring proper physiological functions and reducing the gap between experimental research and clinical outcomes. This gap is particularly evident in drug testing and the use of vascularized models may provide more realistic insights into human responses to drugs in the pre-clinical phases of the drug development pipeline. In this context, different vascularized liver models have been developed to recapitulate the architecture of the hepatic sinusoid, exploiting either porous membranes or bioprinting techniques. In this work, we developed a method to generate perfusable vascular channels with a circular cross section within organs-on-chip without any interposing material between the parenchyma and the surrounding environment. Through this technique, vascularized liver sinusoid-on-chip systems with and without the inclusion of the space of Disse were designed and developed. The recapitulation of the Disse layer, therefore, a gap between hepatocytes and endothelial cells physiologically present in the native liver milieu, seems to enhance hepatic functionality (e.g., albumin production) compared to when hepatocytes are in close contact with endothelial cells. These findings pave the way to numerous further uses of microfluidic technologies coupled with vascularized tissue models (e.g., immune system perfusion) as well as the integration within multiorgan-on-chip settings.
On discrete Lorenz-like attractors in three-dimensional maps with axial symmetry
Authors: Gonchenko Sergey , Gonchenko Aleksandr
Published: December 2023

We describe a class of three-dimensional maps with axial symmetry {x→−x,y→−y,z→z} and the constant Jacobian. We study bifurcations and chaotic dynamics in quadratic maps from this class and show that these maps can possess discrete Lorenz-like attractors of various types. We give a description of bifurcation scenarios leading to such attractors and show examples of their implementation in our maps. We also describe the main geometric properties of the discrete Lorenz-like attractors including their homoclinic structures.
Flow pattern regime and unsteady characteristics of ventilated cavitating flow around the axisymmetric bodies with different headforms
Authors: Hao Liang , Liu Taotao , Kong Decai , Huang Biao , Wang Guoyu , Wu Yue
Published: December 2023

This paper presents an experimental investigation of the flow pattern regime and unsteady characteristics of ventilated cavities with different headform shapes. The test model consists of a removable headform with three different forebodies (the conical, the blunt, and the hemispherical) and a common cylinder rear body. Experiments are conducted in a closed-loop cavitation tunnel. First, the flow pattern regimes on the ventilated cavity for different headforms are discussed in detail, and the dimensions of several flow patterns are measured. The results show that the cavity dimension and the regime are strongly dependent on the headform shape, and all typical flow patterns are introduced by schematic illustrations. Second, the ventilation hysteresis that happened during the flow pattern transition is pointed out. A quantitative gas leakage model is employed to explain the cause of hysteresis and flow pattern transition, and the results show the Strouhal number for different headforms is approximately ∼0.21. However, the blunt presented stronger gas leakage with a large constant parameter, K = 0.80. Finally, the unsteady characteristics of the ventilated cavity around different tested headforms are involved through descriptions of developments of the recirculating vortex and transparent cavity. In addition, an estimated cavitation number is applied to investigate the unsteady characteristics, and the maximum cavitation number and the strongest characteristic are obtained by the blunt headform due to the large drag coefficient and strong flow separation.
Characterization of nanoscale pinhole defects in hydrophobic coatings using copper electrodeposition
Authors: Zarin Ishrat , Arissi Ghassan , Barias Emmanuel , Hoque Muhammad Jahidul , Ma Jingcheng , Rabbi Kazi Fazle , Miljkovic Nenad
Published: December 2023

Thin (∼ 100 nm thick) hydrophobic polymer films are used in a plethora of applications where water repellency is required. However, hydrophobic film implementation in industry is limited due to poor durability. Thin hydrophobic film blistering during condensation has been identified as one of the main mechanisms associated with failure. Yet, disagreement exists about the source of blister initiation. Furthermore, there is a lack of understanding about the physical defects or pinholes that facilitate vapor penetration pathways through thin hydrophobic films. These pinholes govern the nucleation of blisters on the interface between the hydrophobic polymer and metal substrate. Here, we use metal electrodeposition as a means to characterize these intrinsic pinholes in thin hydrophobic polymers. A facile method is demonstrated to locate pinholes and measure pinhole density on CFx and poly(2-chloro-p-xylylene) (Parylene C) films. Our work not only helps to understand the intrinsic defects associated with film deposition, it also provides design guidelines for the selection and development of efficient thin film hydrophobic coatings.
On the behavior of higher harmonics in the evolution of nonlinear water waves in the presence of abrupt depth transitions
Authors: Wu Qian , Feng Xingya , Dong You , Dias Frederic
Published: December 2023

The presence of abrupt depth transitions might trigger strong nonlinear effects on propagating water waves near coastal regions. In this study, the dynamics of nonlinear monochromatic waves over a submerged step representing the abrupt depth transitions are investigated both experimentally and numerically. Within the framework of the free-surface Euler equations, a fully nonlinear potential flow model based on a conformal mapping method is established to investigate the higher harmonics. The numerical method has been well validated with experimental measurements. To analyze the wave nonlinearity at the transitions, the higher harmonics are extracted both in the spatial and time domains. It is shown that abrupt depth transitions enhance the higher harmonic amplitudes in the shallower regions on the step. The effects of the incident wave frequency and height are studied. It is found that the higher harmonics induced by the abrupt depth transitions become more significant with increasing wave steepness. An analysis of the evolution of the skewness and kurtosis demonstrates the high asymmetry of the surface elevation on the upstream junction. The asymmetry shows clear nonlinear effect from the higher harmonics.
Production of 13.5 nm light with 5% conversion efficiency from 2
μ
m laser-driven tin microdroplet plasma
Authors: Mostafa Y. , Behnke L. , Engels D. J. , Bouza Z. , Sheil J. , Ubachs W. , Versolato O. O.
Published: December 2023

We demonstrate the efficient generation of extreme ultraviolet (EUV) light from laser-produced plasma (LPP) driven by 2 μm wavelength laser light as an alternative for 10 μm CO2 gas LPP currently employed in EUV lithography machines for high-volume manufacturing of semiconductor devices. High conversion efficiencies of laser light into “in-band” EUV photons up to 5.0% are achieved by homogeneously heating the plasma that is laser-generated from preshaped tin microdroplet targets. Scaling the laser pulse duration, spot size, and intensity yields a high in-band EUV energy output of up to 12.5 mJ. The EUV emission source size is studied under a similar parameter range and is shown to match typical etendues of EUV optic columns. Our findings make 2 μm LPP a particularly promising candidate to power future EUV nanolithography.
Slip-flow and heat transfer in microtubes with internal fins
Authors: Shome Biswadip
Published: December 2023

The study of the simultaneous development of slip-flow and heat transfer in a microtube with internal fins has been conducted. It was found that rarefaction effects were more pronounced in the entrance region than in the fully developed region for both friction factor and Nusselt number. Minimal influence of the number of fins on rarefaction effects for the friction factor was observed, but a substantial influence on Nusselt numbers was noted. Tubes with larger fin height were found to enhance rarefaction effects on the friction factor, while the opposite was observed for Nusselt number. An evaluation criterion was used to compare the heat transfer and pressure drop in microtubes with and without fins. The results showed that the microtube with fins offers a significant performance advantage, especially in the entrance region and for tubes with a higher number of fins with a larger fin height. This study highlights that microtubes with internal fins have the potential to improve cooling efficiency in electronic circuit cooling applications compared to microtubes without internal fins.