bluuebunny/crossref_metadata_2025 huggingface dataset:
Research on the Phenomenon of Over-promoting Movies in the Era of Short Video
Authors: Liu Ning
Published: June 2024

With the rapid development of information technology, new media, as a typical example of social media, rises abruptly, relying on the Internet, which has caused a strong impact on traditional media. In the era of information fragmentation, domestic films have more chance to catch people's eyes especially through social media, such as Tiktok, Instagram and Youtube. The huge number of users on social media allows film capitalists to target some potential user groups. Whenever a movie is about to be released, filmmakers always choose to vigorously promote it on social media, such as short videos, in order to attract more audiences and attract box office. However, social media itself is a double-edged sword, and marketing methods are sometimes difficult to grasp, and there are countless films that attract attention by exaggerating facts, especially on social platforms where information spreads quickly. This article will study and analyze several common ways and types of over-marketing by using short videos, so as to find out the disadvantages of over-marketing of domestic films, and give a warning and suggestion to the publicity mode of future films.
Research on the Development and Management Mode of the Sports Rehabilitation Industry in China - Based on Global National Experience
Authors: Ge Wenle
Published: June 2024

As a combination of sports, medicine and human health, sports rehabilitation will have great potential and market prospects in the future. As people pay more and more attention to their health and their education level is getting higher and higher, the sports rehabilitation industry will develop rapidly and effectively. The sports rehabilitation industry has also received strong support from national policies, with broad market prospects and continuous enrichment of market elements. This paper retrieves a large number of literature, using the method of comparative analysis, mainly from the analysis of the current development and management mode of China's sports rehabilitation industry, through the comparison with other countries in the world sports rehabilitation industry, draw experience, found that China's sports rehabilitation industry is different from other countries in the world, so as to explore the development mode and road suitable for China's sports rehabilitation industry, and promote the development of China's sports rehabilitation industry.
Novel Approaches for the Analysis and Isolation of Benzylisoquinoline Alkaloids in Chelidonium majus
Authors: Zwerger Michael , Boeck Lynda , Manzl Julia , Schwaiger Stefan , Ganzera Markus
Published: June 2024

Benzylisoquinoline alkaloids are the major bioactive components in Chelidonium majus, a plant that has a long usage history for the treatment of gastrointestinal ailments in European and Asian phytomedicine. This study reports on the development and application of a supercritical fluid chromatography technique for the simultaneous qualitative and quantitative determination of seven benzylisoquinoline alkaloids in under six minutes using a Viridis BEH 2-EP column and a modifier comprising methanol with 30% acetonitrile and 20 mM ammonium formate. The method was fully validated according to ICH guidelines showing, e.g., excellent linearity (≥ 0.9997) and maximum deviations for intraday and inter-day precision of 2.99 and 2.76%, respectively. The new supercritical fluid chromatography assay was not only employed for the analysis of several C. majus samples but was also used for the subsequent development of a fast centrifugal partition chromatography technique,
whereby five benzylisoquinoline alkaloids could be isolated within approximately 2.5 h, with only two of them, protopine and chelidonine, requiring an additional purification step. To achieve this, a solvent system composed of chloroform/methanol/0.3 M hydrochloric acid was used in descending mode. By injecting 500 mg of crude extract, stylopine (1.93 mg), sanguinarine (0.57 mg), chelidonine (1.29 mg), protopine (1.95 mg), and coptisine (7.13 mg) could be obtained. The purity of compounds was confirmed by supercritical fluid chromatography and MS.
Variability of Chalcone Synthase in Chamomile Accessions (Matricaria chamomilla)
Authors: Novak Melanie , Jovanovic Dijana , Novak Johannes
Published: June 2024

Chamomile (Matricaria chamomilla) is an important medicinal plant whose beneficial activities partly rely on certain flavonoids. The first dedicated step in flavonoid biosynthesis is chalcone synthase (CHS, EC 2.3.1.74). The genomic DNA of CHS was studied in six chamomile specimens from different genotypes to describe interspecimen, as well as interspecific, variability. One specimen of M. discoidea was included as an outgroup. The two exons of CHS of M. chamomilla (McCHS) and M. discoidea (MdCHS) were 188 bp and 1,011 bp long, separated by an intron of variable length between 192 and 199 bp in McCHS and 201 bp in MdCHS, respectively. The two exons with 5.3 and 6.2 mutations per 100 bp, respectively, were more conserved than the intron with 11.5 mutations per 100 bp. In total, 96 SNPs were detected in both species, of which 12 SNPs were only present in MdCHS and 80 SNPs only in McCHS. Overall, 70 haplotypes (multilocus genotypes, MLGs) were
detected. The samples could be classified into two groups, a ʼcompactʼ group of a low number and diversity of haplotypes and a ʼvariableʼ group of a high number and diversity of haplotypes. Of the 74 SNPs in McCHS, only six SNPs were non-synonymous. However, the amino acid changes did not affect critical areas of the enzyme. The combination of the six SNPs resulted in nine translated amino acid MLGs. The CHS network located MdCHS, due to the crossing barrier, quite distant from chamomile. MdCHS docked to McCHS at a position from where McCHS divergently evolved into two directions.
Flower Power: An Overview on Chemistry and Biological Impact of Selected Essential Oils from Blossoms
Authors: Prosche Sinah , Stappen Iris
Published: June 2024

Natural raw materials such as essential oils have received more and more attention in recent decades, whether in the food industry, as flavorings and preservatives, or as insecticides and insect repellents. They are, furthermore, very popular as fragrances in perfumes, cosmetics, and household products. In addition, aromatherapy is widely used to complement conventional medicine. This review summarizes investigations on the chemical composition and the most important biological impacts of essential oils and volatile compounds extracted from selected aromatic blossoms, including Lavandula angustifolia, Matricaria recutita, Rosa x damascena, Jasminum grandiflorum, Citrus x aurantium, Cananga odorata, and Michelia alba. The literature was collected from PubMed, Google Scholar, and Science Direct. Blossom essential oils discussed in this work are used in a wide variety of clinical issues. The application is consistently described as safe in studies and
meta-analyses, although there are notes that using essential oils can also have side effects, especially dermatologically. However, it can be considered as confirmed that essential oils have positive influences on humans and can improve quality of life in patients with psychiatric disorders, critically ill patients, and patients in other exceptional situations. Although the positive effect of essential oils from blossoms has repeatedly been reported, evidence-based clinical investigations are still underrepresented, and the need for research is demanded.
Schmerzedukation und Selbstbestimmung
Authors: Lotze Martin , Mehrholz Jan , Menig Alexandra
Published: June 2024

Schmerz ist ein wichtiges Thema in der Neurorehabilitation, weshalb wir auch hier
wieder einen Schwerpunkt setzen möchten. Schmerzen können durch absteigende Bahnen
moduliert werden, und verschiedene kognitive Behandlungsstrategien setzen genau hier
an. In einem Überblick stellt Martin Lotze diese Mechanismen vor und zeigt
Möglichkeiten der Schmerzmodulation auf.
Übersicht zur Schmerzverarbeitung
Authors: Lotze Martin
Published: June 2024

Chronische Schmerzen sind für Therapeutinnen und Therapeuten eine große
Herausforderung. Am liebsten würden wir den Schmerz rasch lindern, was jedoch
unmöglich ist. Die gemeinsame Arbeit mit chronisch von Schmerz betroffenen
Patienten und Patientinnen kann deshalb leicht zu Frustration auf beiden Seiten
führen. Für einen Therapieerfolg ist es gut, dieses Spannungsverhältnis im Auge
zu behalten. Wir wissen aus eigener Erfahrung, wie unterschiedlich wir Schmerz
erleben und bewerten und wie frustrierend es sein kann, wenn die
Reparaturprozesse des Körpers nicht automatisch ablaufen und nach wenigen Wochen
nicht alles wieder einwandfrei funktioniert.
Application of 3Rs in Caenorhabditis elegans Research for the Identification of Health-Promoting Natural Products
Authors: Redl Martina , Shayegan Anusha , Rollinger Judith M.
Published: June 2024

The average age of the population is increasing worldwide, which has a profound impact on our society. This leads to an increasing demand for medicines and requires the development of new strategies to promote health during the additional years. In the search for resources and therapeutics for improved health during an extended life span, attention has to be paid to environmental exposure and ecosystem burdens that inevitably emerge with the extended consumption of medicines and drug development, even in the preclinical stage. The hereby introduced sustainable strategy for drug discovery is built on 3Rs, “Robustness, Reliability, and saving Resources”, inspired by both the 3Rs used in animal experiments and environmental protection, and centers on the usefulness and the variety of the small model organism Caenorhabditis elegans for detecting health-promoting natural products. A workflow encompassing a multilevel screening approach is presented to
maximize the amount of information on health-promoting samples, while considering the 3Rs. A detailed, methodology- and praxis-oriented compilation and discussion of proposed C. elegans health span assays and more disease-specific assays are presented to offer guidance for scientists intending to work with C. elegans, thus facilitating the initial steps towards the integration of C. elegans assays in their laboratories.
Withanolide Profile and Acetylcholinesterase Inhibitory Activity of Two Argentinean Jaborosa Species
Authors: Alza Natalia P. , Pferschy-Wenzig Eva M. , Kunert Olaf , Murray Ana P.
Published: June 2024

Acetylcholinesterase (AChE) inhibitors are still an important option for managing symptoms of mild to moderate Alzheimerʼs disease. In this study, we aimed to evaluate the potential in vitro AChE inhibitory activity of two Argentinian endemic Solanaceae species, Jaborosa bergii and J. runcinata. UHPLC-DAD-HRMS metabolite profiling revealed the presence of withanolides in the active CH2Cl2 subextracts. Their fractionation led to the isolation and identification of two known spiranoid withanolides from J. runcinata and three new withanolides with a skeleton similar to that of trechonolide-type withanolides from J. bergii. The known compounds showed moderate AChE inhibitory activity, while the new ones were inactive.
Schmerzedukation – aktueller denn je
Authors: Bucher-Dollenz Gerti
Published: June 2024

Die immer komplexeren Patientenprobleme verlangen von Therapeuten den bewussten
Einsatz von Edukationsstrategien. Schmerzedukation zählt zu den wichtigsten
edukativen Maßnahmen bei Menschen mit chronischen Schmerzen. Dabei zeigt eine
individualisierte Edukation den größten Effekt. Die wenigsten
physiotherapeutischen Curricula berücksichtigen Schmerzedukation. Diese könnte
jedoch einen wichtigen Schritt in Richtung weiterer Professionalisierung der
Physiotherapie darstellen. Sie ist ein Tool im Rahmen des Patientenmanagements
und sollte ebenso wie andere Herangehensweisen auf metakognitiver Ebene
reflektiert werden.
Akupunktur und Schmerz
Authors: Usichenko Taras
Published: June 2024

Akupunktur, die Therapie mithilfe feinster Nadeln, beruht auf 3000 Jahren
Erfahrung. Sie wurde in China entwickelt und erfreut sich in Europa immer
größerer Beliebtheit. Ihr werden stark schmerzlindernde Qualitäten
zugeschrieben.
Optical Coherence Tomography Angiography Evaluation of
Retinochoroidal Microvascular Circulation Differences in Pregnant Women with
Pregestational and Gestational Diabetes Mellitus
Authors: Pota Çisil Erkan , Doğan Mehmet E , Bülbül Gül Alkan , Sanhal Cem Y , Pota Ali
Published: June 2024

Purpose In this study, the changes in microvascular circulation caused by
pregestational and gestational diabetes were observed, without focusing on
retinal findings, to reveal the effect of diabetes regulation.

Methods A total of 135 subjects were included: 30 with gestational
diabetes (GDM), 30 pregestational diabetes (PGDM), 30 healthy pregnant
normoglycemic subjects, and 45 healthy non-pregnant subjects. All subjects were
examined by optical coherence tomography (OCT) and angiography. The retina,
retinal nerve fiber layer (RNFL), ganglion cell layer (GCL), choroidal thickness
(CT), superficial capillary plexus (SCP), deep capillary plexus (DCP),
choriocapillaris (CC), vascular density (VD), and foveal avascular zone (FAZ)
areas were measured.

Results The foveal VD of SCP and DCP was significantly lower in the PGDM
and GDM groups compared to the control groups (p:0.006 and p:0.001,
respectively). CC VD was significantly higher in all pregnant groups compared to
non-pregnant controls (p<0.001). The choroidal thickness values were highest
in the healthy pregnant group and lowest in the PGDM group. There was no
significant difference in FAZ area, retina, RNFL and GCL thickness between the
groups. In the PGDM group, a negative correlation was observed between the FAZ
area and the HbA1c level (r:− 0.417, p:0.043).

Conclusion There was a decrease in vascular density in pregnant women with
diabetes compared to healthy pregnant women and controls. In the pregnant group
with PGDM, a narrowing of the FAZ area was observed with increasing worsening of
diabetes control. Diabetes type and glycemic control could influence the
microvascular changes even in the absence of clinical or retinal findings.
Toward Alleviating Clinician Documentation Burden: A Scoping Review of Burden Reduction Efforts
Authors: Sloss Elizabeth A. , Abdul Shawna , Aboagyewah Mayfair A. , Beebe Alicia , Kendle Kathleen , Marshall Kyle , Rosenbloom S. Trent , Rossetti Sarah , Grigg Aaron , Smith Kevin D. , Mishuris Rebecca G.
Published: June 2024

Background Studies have shown that documentation burden experienced by clinicians may lead to less direct patient care, increased errors, and job dissatisfaction. Implementing effective strategies within health care systems to mitigate documentation burden can result in improved clinician satisfaction and more time spent with patients. However, there is a gap in the literature regarding evidence-based interventions to reduce documentation burden.

Objectives The objective of this review was to identify and comprehensively summarize the state of the science related to documentation burden reduction efforts.

Methods Following Joanna Briggs Institute Manual for Evidence Synthesis and Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) guidelines, we conducted a comprehensive search of multiple databases, including PubMed, Medline, Embase, CINAHL Complete, Scopus, and Web of Science. Additionally, we searched gray literature and used Google Scholar to ensure a thorough review. Two reviewers independently screened titles and abstracts, followed by full-text review, with a third reviewer resolving any discrepancies. Data extraction was performed and a table of evidence was created.

Results A total of 34 articles were included in the review, published between 2016 and 2022, with a majority focusing on the United States. The efforts described can be categorized into medical scribes, workflow improvements, educational interventions, user-driven approaches, technology-based solutions, combination approaches, and other strategies. The outcomes of these efforts often resulted in improvements in documentation time, workflow efficiency, provider satisfaction, and patient interactions.

Conclusion This scoping review provides a comprehensive summary of health system documentation burden reduction efforts. The positive outcomes reported in the literature emphasize the potential effectiveness of these efforts. However, more research is needed to identify universally applicable best practices, and considerations should be given to the transfer of burden among members of the health care team, quality of education, clinician involvement, and evaluation methods.
Perianal Tuberculosis in an Immunocompetent Patient: Exploring the Uncommon Manifestation
Authors: Ferreira Ana Rita , Pereira Hugo , Castro Bárbara , Ferreira Joana , Esteves Joana , Pereira Bela , Vale Sílvio , Oliveira Manuel
Published: June 2024

As it is an infrequent etiology, the diagnosis of perianal tuberculosis is challenging, especially in the absence of a pulmonary focus. TB should be considered in the differential diagnosis of perianal ulcers, fistulas, abscesses, mainly in non-healing and recurrent anal lesions. Treatment with anti-TB agents can provide complete recovery. Furthermore, these lesions are often diagnosed later after complete histopathological and mycobacterial results, where the benefit of avoiding morbid multiple surgeries by effective anti-TB treatment is lost.

We reported a rare case of an immuno-competent patient with perianal TB, which was the first manifestation of the disease. A fit-and-well man in his 20s presented a large perianal abscess. Unexpectedly, his chest X-ray showed a rounded hyper-transparency in the left lung. The abscess was drained. Posterior investigation with culture analysis from pus swabs and sputum revealed the presence of Mycobacterium tuberculosis complex infection. After completing the 6 months of oral administration of anti-TB drugs, the patient was asymptomatic.

By highlighting this unusual manifestation, we aim to improve clinicians' awareness of perianal TB, facilitating early recognition and appropriate management.
Medical Illustration - A Pictorial Essay Visual Illustration of Obstetric Anal Sphincter Injuries (OASIS) Degrees of Severity, a Picture is Worth a Thousand Words
Authors: Abdulrahman Abdugadir M.
Published: June 2024

Obstetric anal sphincter injury affects about 5.7% of primiparous women who deliver vaginally. Perineal injury during childbirth is a common event with important morbidity associated with third-and-fourth degree perineal tears (also referred to as obstetric anal sphincter injuries—OASIS). As there was a lack of consistency in the classification of a partial anal sphincter injury, with up to 33% of consultant obstetricians classifying a complete or partial tear of the EAS as a second-degree tear. We have proposed simple, digital diagrammatic drawings to visually represent all degrees (grades) of OASIS based on the WHO OASIS classification.
Pflegepersonalbemessung: Was lange währt, wird endlich gut
Authors: Heeser Alexandra
Published: June 2024

Ende April hat der Bundesrat der lang ersehnten neuen Pflegepersonalbemessungsverordnung (PPBV) zugestimmt. Die weithin als PPR 2.0 bekannte Regelung tritt nun mit allen beschlossenen Ergänzungen zum 1. Juli 2024 in Kraft.
Organspenden: Elektronisches Register am Start
Authors: Heeser Alexandra
Published: June 2024

Am 18. März 2024 hat das zentrale elektronische Register zur Organ- und Gewebespende seinen Betrieb aufgenommen. Mit dem Register verspricht sich Gesundheitsminister Prof. Karl Lauterbach (SPD), dass sich die Spendenbereitschaft erhöht.
OP-Management: Wege aus dem Versorgungsdilemma
Authors: Diemer Matthias , Schreiner Catrin
Published: June 2024

Die personellen und finanziellen Ressourcen werden immer knapper, der Bedarf an qualitätsgesicherter Versorgung steigt. Wie kann das in Zukunft funktionieren? Eine Annäherung aus Sicht des OP-Managements, abseits der Krankenhausreform.
E-Health: Stottert der digitale Umbau, Herr Ludewig?
Authors: Doelfs Guntram
Published: June 2024

Dr. Gottfried Ludewig war unter Jens Spahn oberster Digitalisierer des Gesundheitswesens. Inzwischen ist er Chef der internationalen Gesundheitssparte von T-Systems. Im Interview mit kma spricht er über Datenmodelle der Zukunft, über die Zusammenarbeit mit Google – und warum die Klinikreform stärker digital vernetzte Medizin statt Bettenzahlen im Blick haben sollte.
Beruflicher Erfolg in der Medizin: So vermeiden Sie Fehler auf der Karriereleiter
Authors: Napoli Lisanne
Published: June 2024

Die medizinische Laufbahn stellt viele Ärztinnen und Ärzte vor Herausforderungen, bietet aber auch zahlreiche Chancen, langfristig erfolgreich zu sein. Auf dem eigenen Karriereweg gilt es, von Anfang an Stolpersteine zu vermeiden und kluge Entscheidungen zu treffen.
Lernmanagementsysteme: Aktuelle Trends beim E-Learning
Authors: Lang Michael
Published: June 2024

Digitale Weiterbildung wird an Bedeutung zunehmen. Krankenhäuser, die sich in diesem Bereich professioneller aufstellen, zentralisieren ihre Angebote mittels Lernmanagementsystemen. Große Sprachmodelle vereinfachen und beschleunigen die Arbeitsweise mit diesen Systemen.
Sterilgutaufbereitung 4.0: Mit Robotik und KI gegen den Fachkräftemangel
Authors: Reisinger Kathrin
Published: June 2024

Immer häufiger geraten Kliniken bei der Sterilgutaufbereitung unter Druck und an ihre Grenzen. Durch fehlendes Personal treten beim Packen der Siebe vermehrt Fehler auf, Operationen verzögern sich. Am Universitätsklinikum Schleswig-Holstein (UKSH) wird nun der sensible Prozess mithilfe von Automatisierung, Robotik und Künstlicher Intelligenz umgekrempelt.
Gendermedizin: Der große Unterschied
Authors: Kucera Martin
Published: June 2024

Gendermedizin widmet sich den geschlechtsspezifischen Unterschieden von Krankheiten. Obwohl sie als wichtige Einflussfaktoren bekannt sind, gleicht das Bewusstsein darüber hierzulande noch einem Flickenteppich. Wir haben mit jenen Experten gesprochen, die sich für mehr Geschlechtersensibilität in Lehre, Klinik und Praxis einsetzen.
Probabilistic and maximum entropy modeling of chemical reaction systems: Characteristics and comparisons to mass action kinetic models
Authors: Cannon William R. , Britton Samuel , Banwarth-Kuhn Mikahl , Alber Mark
Published: June 2024

We demonstrate and characterize a first-principles approach to modeling the mass action dynamics of metabolism. Starting from a basic definition of entropy expressed as a multinomial probability density using Boltzmann probabilities with standard chemical potentials, we derive and compare the free energy dissipation and the entropy production rates. We express the relation between entropy production and the chemical master equation for modeling metabolism, which unifies chemical kinetics and chemical thermodynamics. Because prediction uncertainty with respect to parameter variability is frequently a concern with mass action models utilizing rate constants, we compare and contrast the maximum entropy model, which has its own set of rate parameters, to a population of standard mass action models in which the rate constants are randomly chosen. We show that a maximum entropy model is characterized by a high probability of free energy dissipation rate and likewise entropy production rate, relative to other models. We then characterize the variability of the maximum entropy model predictions with respect to uncertainties in parameters (standard free energies of formation) and with respect to ionic strengths typically found in a cell.
Significantly enhanced electrostatic energy storage performances of polyetherimide nanocomposites with ultralow loadings of barium titanate nanoparticles
Authors: Liu Jilong , Qu Shaoning , Chen Zhaowei , Ni Jinzhe , Jia Zhiruo , Yin Xunqian , Ma Yong , Li Tingxi
Published: June 2024

With the rapid development of electrical equipment and electronic devices, polymer-based dielectric nanocomposites with high-energy density and low dielectric loss for capacitive energy storage are in great demands. However, the traditional approaches to improve the dielectric constant of polymer by incorporating high loading of inorganic nanofillers with high dielectric constant are always at the expense of breakdown strength (Eb), resulting in limited improvement in energy density of polymer dielectrics. Here, ultralow loadings (≤1 vol. %) of barium titanate (BaTiO3, BT) nanoparticles were incorporated into polyetherimide (PEI) matrix for capacitive energy storage applications. The results show that the simultaneous enhancement of dielectric constant and breakdown strength is achieved in PEI-based nanocomposite with ultralow loading of BT nanoparticles. The nanocomposite with an ultralow loading of 0.4 vol. % BT nanoparticle exhibits a highest discharge energy density of 6.46 J/cm3 (4.8 times that of pure PEI film) and an acceptable charge–discharge efficiency of 77.6% at 500 MV/m. Furthermore, the nanocomposite exhibits improved high-temperature energy storage performance, good long-term reliability, and enhanced discharge capability. Therefore, nanocomposites based on ultralow loading of BT nanoparticles provide a promising approach for the development and application of high-energy-density polymer-based dielectrics.
Nitridation of diamond(111) surface by density functional theory
Authors: Zheng Yusen , Hoffman Alon , Huang Kai
Published: June 2024

Density functional theory was employed to examine the adsorption and thermal evolution of nitrogen species on diamond(111) impacted by microwave N2 plasma. On bare domains of diamond, as represented by the models of C(111)-2 × 1 and graphite-like C(111), N2(ad) is identified as the major surface species; the desorption of N2(ad) proceeds on both models via a concerted process of breaking two C–N bonds. By contrast, there is evidence of the formation of (NH)2(ad) via the insertion reaction of microwave N2 plasma on hydrogenated domains of diamond, as represented by the models of C(111)-2 × 1-H and C(111)-1 × 1-H. Interestingly, contrasting dynamics of desorption of (NH)2(ad) are presented on these two models, that is, via sequential breaking of two C–N bonds on C(111)-2 × 1-H and via concerted breaking of both C–N bonds on C(111)-1 × 1-H. Our results demonstrate that the observed diversity of surface nitrogen species in composition, bonding, vibration, and desorption in prior experiments is linked to domains of a variety of surface terminations and reconstructions on diamond(111).
Integration of conventional surface science techniques with surface-sensitive azimuthal and polarization dependent femtosecond-resolved sum frequency generation spectroscopy
Authors: Huang Zhipeng , Roos Tobias , Tong Yujin , Campen R. Kramer
Published: June 2024

Experimental insight into the elementary processes underlying charge transfer across interfaces has blossomed with the wide-spread availability of ultra-high vacuum (UHV) setups that allow the preparation and characterization of solid surfaces with well-defined molecular adsorbates over a wide range of temperatures. Within the last 15 years, such insights have extended to charge transfer heterostructures containing solids overlain by one or more atomically thin two dimensional materials. Such systems are of wide potential interest both because they appear to offer a path to separate surface reactivity from bulk chemical properties and because some offer completely novel physics, unrealizable in bulk three dimensional solids. Thick layers of molecular adsorbates or heterostructures of 2D materials generally preclude the use of electrons or atoms as probes. However, with linear photon-in/photon-out techniques, it is often challenging to assign the observed optical response to a particular portion of the interface. We and prior workers have demonstrated that by full characterization of the symmetry of the second order nonlinear optical susceptibility, i.e., the χ(2), in sum frequency generation (SFG) spectroscopy, this problem can be overcome. Here, we describe an UHV system built to allow conventional UHV sample preparation and characterization, femtosecond and polarization resolved SFG spectroscopy, the azimuthal sample rotation necessary to fully describe χ(2) symmetry, and sufficient stability to allow scanning SFG microscopy. We demonstrate these capabilities in proof-of-principle measurements on CO adsorbed on Pt(111) and on the clean Ag(111) surface. Because this setup allows both full characterization of the nonlinear susceptibility and the temperature control and sample preparation/characterization of conventional UHV setups, we expect it to be of great utility in the investigation of both the basic physics and applications of solid, 2D material heterostructures.
One-step synthesis of self-assembled directed single-atom-thick gold film on semiconductor
Authors: Liu Shanshan , Yuan Wenjuan , Wang Zirui , Shen Yongli , Xi Wei
Published: June 2024

Two-dimensional metal thin films have received extensive research attention owing to their distinctive physical and chemical properties. The direct synthesis of highly anisotropic monatomic metal layers is challenging owing to the symmetric non-oriented bonds of metals. In this study, we present a one-step synthesis method for preparing single-atom-thick gold films via high-temperature heating. During substrate synthesis, the surface-hanging bonds anchor the gold atoms individually, resulting in self-assembled loaded monolayer gold films. Density function theory calculations show that gold atoms prefer to anchor along the chain direction, resulting in monolayer films with good homogeneity and stability. The electronic structure of these films is completely different from that of bulk gold. This property may endow the films with potential for applications in magnetism, optics, and catalysis.
LIBS diagnostics of Be-based samples with different gas impurities
Authors: Ladygina M. , Gromelski W. , Gasior P. , Roldán A. Marín , Karhunen J. , Paris P. , Jõgi I. , Hakola A. , Likonen J. , Almaviva S. , Ristkok J. , Bhat P. G. , Porosnicu C. , Lungu C. , Veis P.
Published: June 2024

Controlling plasma fuel retained in the plasma facing components of the first wall of a fusion reactor is one of the most important challenges influencing safe operation of the International Thermonuclear Experimental Reactor in the first place. This issue is proposed to be addressed by the laser-induced breakdown spectroscopy (LIBS) diagnostics, which is particularly powerful in studying the near-surface deposits and analyzing their composition. The main goal of the present study is determining the depth profiles of different elements in beryllium-based materials and the possible co-deposited layers that are formed on the walls of the Joint European Torus (JET) fusion device. Depth profiles estimated by LIBS are compared with those measured by secondary ion mass spectrometry, furthermore, the differences are discussed. In particular, the evolution of spectral lines of Be, as well as the main gaseous elements, such as Ne, N, O, and D, incorporated into the samples were extracted at different depths in the layers. LIBS diagnostics allowed making a fairly accurate analysis of the detected spectral lines of the elements on the samples. The effect of variations of the ablation rate and uncertainty that it introduces in LIBS measurements was also discussed. This investigation will have a significant impact on the development of pre-processing algorithms for machine learning models in terms of adaptation models operating on synthetic data for processing experimental spectra and is important from a point of view of LIBS tests being under preparation at JET.
Noise reduction of stochastic density functional theory for metals
Authors: Vu Jake P. , Chen Ming
Published: June 2024

Density Functional Theory (DFT) has become a cornerstone in the modeling of metals. However, accurately simulating metals, particularly under extreme conditions, presents two significant challenges. First, simulating complex metallic systems at low electron temperatures is difficult due to their highly delocalized density matrix. Second, modeling metallic warm-dense materials at very high electron temperatures is challenging because it requires the computation of a large number of partially occupied orbitals. This study demonstrates that both challenges can be effectively addressed using the latest advances in linear-scaling stochastic DFT methodologies. Despite the inherent introduction of noise into all computed properties by stochastic DFT, this research evaluates the efficacy of various noise reduction techniques under different thermal conditions. Our observations indicate that the effectiveness of noise reduction strategies varies significantly with the electron temperature. Furthermore, we provide evidence that the computational cost of stochastic DFT methods scales linearly with system size for metal systems, regardless of the electron temperature regime.
A new canonical reduction of three-vortex motion and its application to vortex-dipole scattering
Authors: Anurag A. , Goodman R. H. , O'Grady E. K.
Published: June 2024

We introduce a new reduction of the motion of three point vortices in a two-dimensional ideal fluid. This proceeds in two stages: a change of variables to Jacobi coordinates and then a Nambu reduction. The new coordinates demonstrate that the dynamics evolve on a two-dimensional manifold whose topology depends on the sign of a parameter κ2 that arises in the reduction. For κ2>0, the phase space is spherical, while for κ2<0, the dynamics are confined to the upper sheet of a two-sheeted hyperboloid. We contrast this reduction with earlier reduced systems derived by Gröbli, Aref, and others in which the dynamics are determined from the pairwise distances between the vortices. The new coordinate system overcomes two related shortcomings of Gröbli's reduction that have made understanding the dynamics difficult: their lack of a standard phase plane and their singularity at all configurations in which the vortices are collinear. We apply this to two canonical problems. We first discuss the dynamics of three identical vortices and then consider the scattering of a propagating dipole by a stationary vortex. We show that the points dividing direct and exchange scattering solutions correspond to the locations of the invariant manifolds of equilibria of the reduced equations and relate changes in the scattering diagram as the circulation of one vortex is varied to bifurcations of these equilibria.
Subsonic intake under crosswinds: Flow control using pulsed vortex generator jets
Authors: Arasu Adrin Issai , Vadlamani Nagabhushana Rao
Published: June 2024

Ultra-high bypass ratio engines are soon expected to become the norm in the civil aircraft engine industry due to their superior efficiency and lower emissions compared to traditional turbofan engines. Shorter intakes with slimmer lips employed in such engines are more prone to flow separation under off-design conditions and incur severe performance penalties. This study examines the efficacy of several pulsed vortex generator jet (VGJ) configurations on flow distortion within a subsonic intake under strong crosswinds (approaching at 90°). High-fidelity scale-resolving simulations are carried out to study the effect of different pulsing frequencies and the duration of the duty cycles of the VGJs toward mitigating the inlet distortion. Several VGJs are employed on both the windward (outer jets) and leeward sides (throat and diffuser jets) of the intake distributed along its circumference. Different pulsing strategies including blowing-alone, zero-net-mass-flux (ZNMF) jets (with both blowing and suction), and steady suction are tested. Through a detailed examination of instantaneous and time-averaged flow fields, we uncover the nuanced influence of pulsed jets on flow behavior. When compared to the baseline case without control, all the simulations with pulsed jets showed a ≈ 50%–60% reduction in the radial extent of distortion at the fan face. Increasing the duration of the duty cycle promotes wall-normal mixing due to the increased penetration of the jet shear layers into the crossflow. The VGJ configuration with a 50% duty cycle operating at a frequency of 8 pulses per flow-through is found to be optimal. Of all the flow control strategies, the test case with steady suction resulted in an optimal flow control decreasing the distortion coefficient by 37%. The suction phase in the ZNMF jets is also found to be instrumental in ingesting the separation. The distortion coefficient at the fan face is reduced by ≈20% with ZNMF jets in contrast to ≈12.7% with the optimal blowing-alone strategy.
Step-like initial value problem and Whitham modulation in fluid dynamics to a generalized derivative nonlinear Schrödinger equation
Authors: Liu Bingyu , Zhao Qiulan , Li Xinyue
Published: June 2024

In this paper, we study the step-like initial value problem for a generalized derivative nonlinear Schrödinger equation using the Whitham modulation theory. First, we utilize the finite-gap integration method to obtain the periodic solutions and the relevant Whitham equations for the 0-, 1-, and 2-genus cases used to characterize dispersive shock waves (DSWs). Second, we investigate four fundamental waves: two rarefaction waves (RWs) and two DSWs with step-like initial data. On this basis, we show the effect of varying certain parameters on the dynamics of the fluid model. We find that the boundary value, amplitude, and shape of the wave pattern in the fluid dynamics model will be significantly impacted by these parameters. Third, under two step-like initial data, waves are divided into six cases, which are actually combinations of DSWs and RWs. Finally, the dam break problem is explored to prove the effectiveness of the Whitham modulation theory in physical applications.
Theoretical interpretation of W soft X-ray spectra collected by the pulse height analysis system on Wendelstein 7-X stellarator
Authors: Syrocki Ł. , Kubkowska M. , Jabłoński S. , Neuner U. ,   W7-X Team
Published: June 2024

In many fusion devices, such as tokamaks or stellarators like Wendelstein 7-X (W7-X), soft x-ray pulse height analysis (PHA) system diagnostics are routinely used during the experiments. The PHA system is dedicated to providing information about the impurity content, and average along line-of-sight electron temperature in the plasma conditions. Moreover, it is also able to estimate impurity density and an average effective charge from the comparison of experimental spectra with the modeled ones. However, the experimental x-ray spectra can be interpreted in terms of interesting plasma parameters only when the theoretical radiation models first identify and then take into account all the relevant factors that affect the spectrum. Therefore, for this purpose, a theoretical model has been applied. Flexible Atomic Code, which allows for calculation of various atomic properties such as energy levels, cross sections for excitation and ionization by electron impact, transition probabilities for radiative transitions and autoionization, and any others as needed in the collisional–radiative approximation. The chosen spectra collected during the W7-X campaign (OP1.2b) were examined, trying to obtain an agreement between the observed and simulated spectra. The analysis carried out allowed for a reliable interpretation of experimental x-ray spectra, estimation of the electron temperature, and obtaining information on the content of tungsten impurities.
Mixing water, sugar, and lipid: Conformations of isolated and micro-hydrated glycolipids in the gas phase
Authors: Camiruaga Ander , Gouasmat Alexandra , Beau Jean-Marie , Bourdreux Yann , Causse Maélie , Chapelle Nathan , Doisneau Gilles , Goldsztejn Gildas , Urban Dominique , Çarçabal Pierre
Published: June 2024

Both sugars and lipids are important biomolecular building blocks with exceptional conformational flexibility and adaptability to their environment. Glycolipids bring together these two molecular components in the same assembly and combine the complexity of their conformational landscapes. In the present study, we have used selective double resonance vibrational spectroscopy, in combination with a computational approach, to explore the conformational preferences of two glycolipid models (3-0-acyl catechol and guaiacol α-D-glucopyranosides), either fully isolated in the gas phase or controlled interaction with a single water molecule. We could identify the preferred conformation and structures of the isolated and micro-hydrated species and evidence of the presence of a strong water pocket, which may influence the conformational flexibility of such systems, even in less controlled environments.
Cation-induced formation of highly active
γ
-NiFeOOH for efficient oxygen evolution reaction
Authors: Ou-Yang Zhen-Yang , Nie Jianhang , Xie Meng-Yuan , Xian Ming-Hua , Shi Jinghui , Wan Hui , Huang Gui-Fang , Huang Wei-Qing
Published: June 2024

The oxygen evolution reaction (OER) activity of Ni-based oxyhydroxides greatly hinges on their phase structures, which are mainly γ and β phases: the former has higher intrinsic activity than the latter. However, it is still a grand challenge to purposefully generate γ phase, rather than β phase. Here, we propose a cation-doping strategy to generate γ phase by taking Zn-doped NiFeP/N-doped C (Z-NFP/N-C) precatalyst as a model. In contrast to the case of NFP/N-C that can only be reconstructed into β-NiFeOOH, Zn dopant will induce the formation of γ-NiFeOOH during an electrochemical process. Specifically, the doped Zn cation will promote the dissolution of NiFeP and redeposition of NiFeOOH on the surface. Simultaneously, the cation defects generated by Zn leaching will force the surrounding Ni valence state to rise for charge balance and will attract more K+ in the solution to intercalate into the interlayer of NiFeOOH, resulting in the formation of γ-NiFeOOH. As a result, the γ-NiFeOOH/Z-NFP/N-C exhibits superior OER performance: a low overpotential of 216 mV at 10 mA cm−2 and satisfactory stability (100 h at 17 mA cm−2). Our study offers a practical approach to produce highly active “true catalyst” for efficient water splitting.
Aerodynamic simulations of an electric vertical takeoff and landing aircraft using reformulated vortex particle method
Authors: Wei Jun , Gao Wei , Gao Wenxuan , Lu Bei , Li Qifu
Published: June 2024

As the population of the world's major cities increases, urban ground transportation capability reaches its limits. Consequently, electric vertical takeoff and landing aircraft have been developed to address this issue. Modern vertical takeoff and landing designs vary in configurations, each possessing distinct aerodynamic properties. In this work, we focus on the interaction between rotors and fixed wings in a parallel layout, using a prototype with an unconventional configuration as an example. The interaction between the slipstream of rotors and the wake of fixed wings is analyzed using the vortex particle method. Actuator surface model is used to deal with the boundary problem between the wing and the rotors. The applicability of the simulation method adopted in this paper is verified through experimental tests on the thrust and torque of the rotors. The results indicate that under the condition of forward flight at zero angle of attack, the existence of rotor slipstream induces a significant increase by three to four times the local lift on the wing. Correspondingly, under vertical takeoff and hovering conditions, the existence of the rotor slipstream causes the local effective velocity and circulation of the wing to increase. On the other hand, at zero angle of attack and a forward flight, the lift coefficient of the rear rotors increases slightly due to the presence of the wing wake. The lift distribution of the rear rotors along the radial direction also changes greatly.
Flexible terahertz spoof plasmonics based on graphene-assembled films
Authors: Zhang Bohan , He Dapeng , Zhang Qian , Fang Jiaxing , Lu Xueguang , Huang Wanxia , Chen Zibo , He Daping , Kang Lei , Werner Douglas H. , Wang Shengxiang
Published: June 2024

Spoof plasmonics, which can enable strong terahertz (THz) radiation–matter interactions, hold great promise for the advancement of THz science and technology. However, THz spoof plasmonic devices based on micro-structured metals are in general limited by lithography-based fabrication processes as well as metals' mechanical, chemical, and thermal stability, which hinders their applications in, for instance, flexible and wearable THz imaging and communications, molecular sensing, etc. Possessing high electrical conductivity and outstanding mechanical robustness, graphene-assembled films (GAFs) promise many benefits for electronics as an alternative to metals. Here, by studying the resonance-enhanced transmission properties of subwavelength GAF hole arrays, we demonstrate a GAF metasurface as a transformative platform for flexible THz spoof plasmonics. Based on a laser direct writing (LDW) patterning technique, the proposed micro-engineered GAF is expected to pave the way toward large-area, durable, and inexpensive THz metadevices with superior flexibility.
Investigation of injector-coupled combustion dynamics in a methane–oxygen combustor using large eddy simulation and dynamic mode decomposition
Authors: Sharma Abhishek , De Ashoke , Kumar Sunil
Published: June 2024

This paper uses a reactive flow large eddy simulation (LES) and decomposition techniques to study combustion instabilities in a methane–oxygen combustor. This work examines two case scenarios to elucidate the significance of injector–chamber frequency coupling as the cause of thermo-acoustic instability. Initial investigation in a well-known benchmark case of the continuously variable resonance combustor (CVRC) reports the potential instability mechanisms and the role of injector–chamber frequency coupling in thermo-acoustic instability. Subsequently, the multi-element rocket combustor case study identifies the critical resonant modes and highlights potential frequency coupling between the injector and the chamber region. The interplay between longitudinal pressure oscillations in the oxidizer post and transverse pressure waves in the chamber is responsible for the enhanced pressure dynamics in the combustor. The present work uses the dynamic mode decomposition (DMD) technique to reveal the evolution of acoustic modes in the injector and the chamber for CVRC and multi-element combustor. The dominant pressure mode forms found by DMD analysis also showcase the role of injector–chamber frequency coupling in amplified combustion dynamics. The results demonstrate how the predominant cause of combustion instability in rocket combustors can be effectively determined using the high-fidelity LES framework in conjunction with the modal decomposition technique.