bluuebunny/crossref_metadata_2025 huggingface dataset:
Low-power supralinear photocurrent generation via excited state fusion in single-component nanostructured organic photodetectors
Authors: Antoniou Giannis , Yuan Peisen , Koutsokeras Loukas , Athanasopoulos Stavros , Fazzi Daniele , Panidi Julianna , Georgiadou Dimitra G. , Prodromakis Themis , Keivanidis Panagiotis E.
Published: April 2022

Columnar arrangement of triplet emitters in the photoactive layer of vertically-configured photodetectors enables photocurrent generation via triplet–triplet annihilation of dimer species.
To be or not be (in the LAD): emerging roles of lamin proteins in transcriptional regulation
Authors: Nazer Ezequiel
Published: April 2022

Lamins are components of the nuclear lamina, a protein meshwork that underlies the nuclear membrane. Lamins interact with chromatin in transcriptionally silent regions defined as lamina-associated-domains (LADs). However, recent studies have shown that lamins regulate active transcription inside LADs. In addition, ChIP-seq analysis has shown that lamins interact with lamin-dependent promoters and enhancers located in the interior of the nucleus. Moreover, functional studies suggest that lamins regulate transcription at associated-promoters and long-range chromatin interactions of key developmental gene programs. This review will discuss emerging, non-canonical functions of lamins in controlling non-silent genes located both inside and outside of LADs, focusing on transcriptional regulation and chromatin organization in Drosophila and mammals as metazoan model organisms.
Die Rechtsfrage: Welche Folgen hat das neue Infektions-schutzgesetz?
Authors: Schlegel Thomas
Published: April 2022

„Das Infektionsschutzgesetz wurde aufgrund der Coronalage geändert. Seit dem 16. März 2022 gelten für Gesundheitseinrichtungen neue Regeln. Welche Konsequenzen ergeben sich daraus für Therapiepraxen – sofern vom Bundesland nicht anders entschieden?“

Therapeut aus Baden-Württemberg
Hormonyoga – Wellness oder ernst zu nehmende Therapie?
Authors: Gupta Hedwig
Published: April 2022

Hormonyoga ist eine moderne, sehr anspruchsvolle und intensive Form der Yogapraxis, die von Dinah Rodrigues entwickelt wurde, um Frauen mit menopausalen oder anderen gynäkologischen Störungen zu behandeln. Zu Yoga in der Therapie von post- und perimenopausalen Beschwerden, zu Menstruationsstörungen und anderen gynäkologischen Leiden gibt es bislang einzelne wissenschaftliche Untersuchungen, die insgesamt eine Wirksamkeit von Yoga in diesem Bereich nahelegen, aber nicht hinreichend belegen können. Zur Frage der hormonellen Veränderung liegen derzeit nur einzelne Fallberichte vor. Auch fehlt eine wissenschaftliche Evaluation eines Mehrgewinns des Hormonyoga zu anderen Formen des Yoga. Dennoch ist Yoga per se im Management gynäkologischer Störungen empfehlenswert, gut umsetzbar und ohne bekannte Nebenwirkungen. Die Form des Hormonyoga nach Rodrigues kann aus vedischer Sicht als Intensivierung und Fokussierung der Yogapraxis angesehen werden, sodass eine verstärkte Wirkung durchaus nachvollziehbar wäre. Weitere Studien hierzu sind unbedingt wünschenswert.
Osteoartikuläre und rheumatologische Manifestationen sexuell übertragbarer Infektionen
Authors: Hornuss Daniel , Giesen Roland , Rieg Siegbert
Published: April 2022

Sexuell übertragbare Infektionen (STI) können Symptome einer rheumatologischen Erkrankung imitieren oder das Auftreten einer solchen begünstigen. Insbesondere chronisch verlaufende Erkrankungen wie HIV oder Syphilis stellen den Kliniker aufgrund der mannigfaltigen Symptomkomplexe vor große Herausforderungen. Andere sexuell übertragbare Erreger wie Chlamydien oder Gonokokken können ebenfalls autoimmunologische Inflammationsreaktionen oder akute septische Arthritiden hervorrufen. Vor Einleitung einer immunmodulierenden Therapie sollte daher eine Abklärung hinsichtlich sexuell übertragbarer Infektionen in Betracht gezogen werden. Dies gilt insbesondere bei jüngeren, sexuell aktiven Patient*innen oder Patientengruppen mit Risikoverhalten (z. B. MSM, Sex-Arbeiter*innen). Bei Nachweis einer STI sollte stets ein Screening auf mögliche Co-Infektionen mit weiteren STI erfolgen.
Virusassoziierte Arthritiden
Authors: Andreica Ioana
Published: April 2022

Die virusassoziierte Arthritis macht etwa 1 % aller akuten Arthritiden aus. Obwohl eine Vielzahl der Viren eine Arthritis verursachen können, hat sich das Spektrum der am häufigsten vorkommenden virusassoziierten Arthritiden im Zeitverlauf geändert. Während eine Röteln-assoziierte Arthritis heutzutage und dank Impfmaßnahmen deutlich seltener geworden ist, hat eine Chikungunya-assoziierte Arthritis an Bedeutung gewonnen. Durch die Ausbreitung dieser Erkrankungen hat in diesem Kontext eine Hepatitis-B- oder -C-induzierte Arthritis eine bedeutsame Relevanz. Die Parvovirus-B19-assoziierte Arthritis ist differenzialdiagnostisch, insbesondere bei begleitenden Hautveränderungen, zu berücksichtigen. In der jetzigen Zeit des Klimawandels und Welttourismus haben die durch Arboviren assoziierten Arthritiden viel an Bedeutung gewonnen. In der Pathophysiologie einer solchen Arthritis hat die direkte virale Invasion der Gelenkstrukturen, die Entwicklung von Immunkomplexen und das Auftreten einer Immundysregulation eine wichtige Rolle. Die Arthritis kann unterschiedliche Muster aufweisen, ist in der Regel selbstlimitierend und hinterlässt keine Gelenkschäden. Sie wird häufig von anderen klinischen Merkmalen, die für die Differenzialdiagnose wichtig sind, begleitet. Die Laboruntersuchungen spielen in der Diagnosestellung eine untergeordnete Rolle und sind nur mit zeitlichen Verlaufsmustern relevant. Die Therapie ist bis auf bestimmte Ausnahmen in den meisten Fällen symptomatisch.
„Nenn mir eine Situation in der Physiotherapie, die nichts mit Umwelt zu tun hat!“ – Environmental Physiotherapy Association
Authors: Czernik Claudia
Published: April 2022

Filip Maric ist Gründer der Environmental Physiotherapy Association. Im Interview erklärt er, warum Physiotherapie ohne Umwelt gar nicht zu denken ist und welche Vision der internationale Zusammenschluss von Physiotherapeut*innen verfolgt. Eins sei schon mal vorweggenommen: Es ist eine Einladung zum Weiterdenken.
Gebrochener Körper – Nachbehandlung thorakolumbaler Wirbelkörperfrakturen
Authors: Zahn Robert , Steinmeier Annika , Wilck Andrea
Published: April 2022

Ob Traumata oder Osteoporose – die Ursachen von Wirbelkörperfrakturen sind vielfältig. So auch ihre Nachbehandlung. Nicht immer ist eine OP indiziert. Kommt es aber dazu, haben in der Physiotherapie Patientenedukation, Schulung von selbstständigen Transfers und die Aktivitäten des täglichen Lebens oberste Priorität.
Wo bitte geht es nach Hinterdupfing? – Denk- und Bewertungssysteme Teil 3
Authors: Hertlein Margit
Published: April 2022

Links oder rechts? Täglich treffen Menschen Entscheidungen. Manchmal ist die Antwort glasklar, manchmal aber eben auch nicht. Wie Sie kluge Entscheidungen treffen, lesen Sie in unserem dritten Teil über den Strudelwurm.
Sexualisierte Gewalt und Machtmissbrauch im Kontext von
Psychotherapieinstituten – Erkenntnisse aus einer institutionsbezogenen
Fallstudie
Authors: Caspari Peter , Caspari Cornelia
Published: April 2022

Der Fall des Leiters eines Instituts für analytische Kinder- und
Jugendlichen-Psychotherapie, der in den Jahren 1975–1993 sexualisierte
Gewalt gegen Patient*innen und Ausbildungskandidatinnen verübte,
wurde in einer aktuellen, qualitativen Studie wissenschaftlich untersucht. Die
Ergebnisse verweisen auf persistierende Risikopotenziale im Kontext der
Behandlung von Patient*innen und der Ausbildung von
Psychotherapeut*innen, die nach wie vor umfangreiche präventive
Anstrengungen erforderlich machen. Dabei sind insbesondere
Machtverhältnisse, institutionelle Pragmatiken und emotionale
Verstrickungen in Augenschein zu nehmen.
Effizient kommunizieren – Elektronischer Heilberufsausweis für Physiotherapeut*innen
Authors: Aschoff Frank
Published: April 2022

Papierlos, einfach und schnell mit anderen Leistungserbringenden kommunizieren, das ist sicher schon lange ein Traum vieler, die im Gesundheitssystem arbeiten. Was wäre, wenn man beispielsweise nicht mehr mühselig wichtige Befunde zusammensuchen müsste? Nach jahrelanger Verzögerung soll dieser Traum bis 2026 auch für Physiotherapeut*innen Realität werden. Der erste Schritt für sie ist die Beantragung des Heilberufsausweises, dessen Ausgabe nun startet.
Validity and Reliability of Two Near-infrared Spectroscopy Devices to
Measure Resting Hemoglobin in Elite Cyclists
Authors: Gandia-Soriano Alexis , Salas-Montoro José-Antonio , Javaloyes Alejandro , Lorente-Casaus Carlos , Zabala Mikel , Priego-Quesada Jose Ignacio , Mateo March Manuel
Published: April 2022

A new method to monitor internal training load from muscle oxygen saturation
using near-infrared spectroscopy could be of practical application for research
and training purposes. This technology has been validated in different
scientific fields, including sports science, and Humon Hex and Moxy are two
leading brands. However, its relationship with hemoglobin has not been studied.
Forty-eight professional cyclists, 19 men and 29 women, underwent a blood test
to measure hemoglobin in the early morning. Immediately afterwards, hemoglobin
and muscle oxygenation were monitored at rest by Moxy and Humon Hex on their
right quadriceps (where the skinfold was measured). Venous blood hemoglobin was
higher than the measurement for both devices (p<0.001). Both
hemoglobin (p<0.001) and muscle oxygen saturation measurements
(p<0.05) were higher in Humon Hex than for Moxy, and there
was a reasonable reproducibility (ICC=0.35 for hemoglobin and 0.26 for
muscle oxygen saturation). Skinfold had an inverse relationship with hemoglobin
measurement (r=–0.85 p<0.001 for Humon Hex
and r=–0.75 p<0.001 for Moxy). These
findings suggest that resting hemoglobin data provided by these devices are not
coincident with those of blood sample, and skinfold has an inverse relationship
with blood hemoglobin measurement.
Catalyst-Controlled Chemodivergent [3+3] and [3+2] Formal Cycloadditions of Azomethine Ylides with Diphenylcyclopropenone
Authors: Adrio Javier , Carretero Juan C. , Corpas Javier , Ponce Alberto , Maclean Ian
Published: April 2022

Chemodivergent cycloadditions of azomethine ylides with diphenylcyclopropenone involving either Cu-catalyzed [3+3] or Ag-catalyzed [3+2] processes have been developed. These transformations provide a highly efficient method for the preparation of a variety of aromatic substituted dihydropyridinones and dihydropyrrolones with excellent regio and diasteroselectivities.
Tropismo/inclinação facetária e sua associação com hérnia de disco intervertebral na região lombar da coluna – Uma avaliação radiológica
Authors: Yadav Sanjay , Arya Rajkumar , Dakshinamoorthy Raghul , Jha Abhinav Anand , Jain Shivi , Kumar Ishan
Published: April 2022

Objetivo Avaliar o papel do tropismo facetário (TF) no prolapso discal intervertebral.

Métodos Um total de 98 pacientes com dor lombar foram incluídos no estudo. Exames de ressonância magnética foram realizados e analisados, e os ângulos das facetas direita e esquerda foram medidos na seção axial. Os pacientes sem prolapso discal nos níveis L3-L4, L4-L5 e L5-S1 atuam como controles para aqueles com prolapso nos mesmos níveis. Fez-se também uma análise estatística.

Resultados A incidência de TF no nível L3-L4 foi de 85,2% em pacientes com hérnia discal (n = 27), e de 56,3% no grupo controle, o que foi estatisticamente significativo (p = 0,008). Da mesma forma, a incidência de TF no nível L4-L5 entre casos e controles foi de 71,4% (n = 35) e 52,4%, respectivamente (p = 0,066). No nível L5-S1, a incidência foi de 66% e 51% nos caso e nos controles, respectivamente (p = 0,13).

Conclusão Encontramos associação positiva entre TF e hérnia de disco no nível L3-L4, mas nenhuma associação nos níveis L4-L5 e L5-S1.
Juvenile Xanthogranuloma as Differential Diagnosis of a Vulvar Mass: A Case Report
Authors: Bada Bosch Isabel , Cañizo Agustín del , Campos-Domínguez Minia , Ordoñez Javier , Blanco Verdú María Dolores , Fanjul María , Pérez-Egido Laura , de Agustín Juan Carlos
Published: April 2022

Vulvar masses in children are an unusual finding but their differential diagnosis is extensive. In case of solid masses, rhabdomyosarcoma (RMS) must always be considered due to the fact that it is the most common tumor in external genitals during childhood. However, RMS has a radiological appearance very similar to juvenile xanthogranuloma (JXG). We present a 16-month-old girl with a 2 cm solid mass on her left labia majora, with four overlying cutaneous papules. After imaging tests, an excisional biopsy was programmed due to high malignancy suspicion. Histopathology of the mass and one of the papules was diagnostic for JXG. After a 12-month follow-up, the patient shows no signs of relapse or complication. Deep JXG is an uncommon entity in childhood and exceptional in the genital area. Therefore, it must be included in the differential diagnosis of a solid vulvar mass, especially if accompanying yellowish xanthomatous cutaneous lesions are present.
The Association of Neurosurgeons in the German Democratic Republic and its First Congresses in Divided Germany
Authors: Synowitz Michael , Rosenow Detlef , Synowitz Hans-Joachim
Published: April 2022

The German Society of Neurosurgery (DGNC) was founded in Bonn in 1950 and saw itself as the all-German representation of neurosurgeons. The development of neurosurgery in divided Germany was different in each case as part of a system and was not unaffected by the confrontation between the two blocs (cold war), which also had a negative impact on the field of science. Thus, early on, restrictions on intra-German travel from the East made normal relations difficult. But travel restrictions also came from the West, where an Allied Travel Office in West Berlin decided whether an East German could enter a North Atlantic Treaty Organization (NATO) country. Nevertheless, it was possible that Georg Merrem from Leipzig took over the second chairmanship of the board of the DGNC of the election period from 1960 to 1962 and eight individual memberships of German Democratic Republic (GDR) neurosurgeons were still tolerated by the state side. The construction of the Berlin Wall on August 13, 1961 meant that these connections also collapsed. Merrem, at that time the only full professor of neurosurgery in the GDR, founded the “Association of Neurosurgeons in the GDR” in 1962 in agreement with the state authorities. With the foundation of a GDR neurosurgeons' society, the demarcation from the DGNC desired by the state was visibly accomplished. There were no official relations between the two neurosurgical societies. During the period of its existence until 1990, the entire work of the East German society was under the guidance and control of state institutions, which in turn derived their work from the guidelines of the party and the decisions of the council of ministers. Using the example of the congress activities of the first 5 years after the Wall was built, we show this dependence on state institutions. It extends from congress planning to reporting. With available figures of participating speakers from West Germany and other countries, it is demonstrated for the individual congresses in Leipzig, Magdeburg, and Erfurt that the German–German connection was continued despite all adverse circumstances. The presence of West German colleagues, who were not deterred from attending the congress even by the construction of the Berlin Wall, can be seen as a visible expression of an unbroken togetherness. However, already in 1967, the party and the council of ministers passed the resolution “On the organization of work in the field of science and culture of the GDR to West Germany as well as West Berlin.” This regulated membership, the associated travel, and the conditions for publications in West German journals. Among other things, this directive prohibited membership in scientific societies, including the DGNC, based in West Germany. The organization of its own congresses took on a special significance because a congress visit from East to West was regulated by the state and thus only possible in isolated cases.
Molecular Detection of Carbapenemase Enzymes Directly from Positive Blood Cultures Using Xpert Carba-R
Authors: Nayak Gayatree , Behera Bijayini , Mahapatra Ashoka , Tripathy Swagata , Biswal Jyoti
Published: April 2022

Objective The performance of Xpert Carba-R assay for the direct identification of carbapenemases directly from positive blood culture vials was evaluated.

Materials and Methods In total, 176 positively flagged blood culture vials, yielding carbapenem-resistant GNB (CR-GNB), were enrolled for the detection and differentiation of blaKPC, blaNDM, blaVIM, blaOXA-48, and blaIMP using Xpert Carba-R.

Results Klebsiella pneumoniae (76/176, 43.1%), Acinetobacter baumannii complex (67/176, 38%), and Escherichia coli (29/176,16.4%) were the predominant isolates. Overall, NDM production was the commonest (61/176, 34.6%), followed by the co-production of NDM + OXA-48 and the absence of any CR gene (44/176, 25%), followed by OXA-48 (27/176, 15.3%). In CR K. pneumoniae, the co-production of NDM + OXA-48 was most frequent (34/76, 44.7%), whereas in the A. baumannii complex, no CR gene was detected in the majority of isolates (38/67, 56.7%). bla NDM was the commonest gene in E. coli (18/29, 62%) and A. baumannii complex (26/67, 38.8%).

Conclusion Xpert Carba-R can identify the molecular mechanism of CR within hours after a blood culture turns positive and, thus, has the potential for optimization of antimicrobial therapy, choosing appropriate novel β-lactam combination agents, as well as infection control interventions.
Safe Technique of Coronary Button Preparation in Redo Bentall Operation
Authors: Ohira Suguru , Malekan Ramin , Kai Masashi , Spielvogel David
Published: April 2022

We introduce a technique of coronary button reconstruction in performing a redo Bentall procedure. A coronary button is prepared leaving a 3 to 4 mm rim of old Dacron graft surrounding the previous button. The Dacron rim may be sewn to the new aortic root graft directly or via an interposed 8- or 10-mm graft, using a modified Cabrol technique. If the button is comprised of good tissue and can be well-mobilized, it is removed from the Dacron rim and anastomosed directly to the new Dacron graft.
Mechanical Ventilation for COVID-19 Patients
Authors: Brioni Matteo , Meli Andrea , Grasselli Giacomo
Published: April 2022

Non-invasive ventilation (NIV) or invasive mechanical ventilation (MV) is frequently needed in patients with acute hypoxemic respiratory failure due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. While NIV can be delivered in hospital wards and nonintensive care environments, intubated patients require intensive care unit (ICU) admission and support. Thus, the lack of ICU beds generated by the pandemic has often forced the use of NIV in severely hypoxemic patients treated outside the ICU. In this context, awake prone positioning has been widely adopted to ameliorate oxygenation during noninvasive respiratory support. Still, the incidence of NIV failure and the role of patient self-induced lung injury on hospital outcomes of COVID-19 subjects need to be elucidated. On the other hand, endotracheal intubation is indicated when gas exchange deterioration, muscular exhaustion, and/or neurological impairment ensue. Yet, the best timing for intubation in COVID-19 is still widely debated, as it is the safest use of neuromuscular blocking agents. Not differently from other types of acute respiratory distress syndrome, the aim of MV during COVID-19 is to provide adequate gas exchange while avoiding ventilator-induced lung injury. At the same time, the use of rescue therapies is advocated when standard care is unable to guarantee sufficient organ support. Nevertheless, the general shortage of health care resources experienced during SARS-CoV-2 pandemic might affect the utilization of high-cost, highly specialized, and long-term supports. In this article, we describe the state-of-the-art of NIV and MV setting and their usage for acute hypoxemic respiratory failure of COVID-19 patients.
Comparison of Chronic Postsurgical Pain Between Single-Port and Multi-Port Video-Assisted Thoracoscopic Pulmonary Resection: A Prospective Study
Authors: Jin Juying , Du Xunsong , Min Su , Liu Ling
Published: April 2022

Background Little is known about the prevalence of chronic postsurgical pain (CPSP) among patients receiving single-port video-assisted thoracic surgery (SP-VATS) compared with those undergoing multi-port VATS (MP-VATS). This study aimed to compare the incidence of CPSP between SP-VATS and MP-VATS lung resection and assess how the pain affected the daily living activities of this patient population.

Methods We prospectively collected data regarding the demographic features, clinical factors during surgery, the intensity of acute postoperative pain, and complications after surgery among patients receiving elective SP-VATS or MP-VATS lung resection at our institution between June 2015 and August 2018. At 3-, 6-, and 12-months following surgery, the patients were followed up through a telephonic interview. The Brief Pain Inventory-Short Form was adopted to assess the incidence, severity and location of the CPSP, analgesic consumption, as well as the interference of pain with daily activities.

Results In total, 476 patients were screened for eligibility, 411 patients were followed up for 12 months and included in final analysis. Among these, 190 patients had undergone an SP-VATS pulmonary resection and 221 had an MP-VATS pulmonary resection. At both 3 and 6 months, the incidence of CPSP in the SP-VATS group was lower than that in the MP-VATS group (25.3 vs. 38.0%, p = 0.006; 11.1 vs. 19.0%, p = 0.026, respectively). At 12 months after surgery, the prevalence of CPSP was comparable between groups (4.7 vs, 9.0%, p = 0.089). In addition, the SP-VATS technique alleviated pain interference with the daily living activities of patients with CPSP in several domains, including sleep, mood, and enjoyment of life compared with the MP-VATS technique. The two predictive factors for CPSP at postoperative 3 months were the MP-VATS technique (odds ratio [OR] = 1.792, p = 0.019) and postoperative chemotherapy (OR = 1.718, p = 0.033).

Conclusions This study indicated that the SP-VATS technique reduced the prevalence of CPSP at 3- and 6-months post-pulmonary resection compared with the MP-VATS technique. The SP-VATS technique also significantly alleviated pain interference with the daily living activities of the patients.
Gurney velocity modification for detonation-driven steel cylindrical casings
Authors: Wang Xinying , Wang Shushan , Ma Feng
Published: April 2022

Detonation-driven experiments for 2,4,6-trinitrotoluene in standard copper cylindrical casings and in 50SiMnVB and 45 steel cylindrical casings with three thicknesses were carried out in this study. The results showed that due to the influences of the coupled loading of the shock waves and the detonation products, the initial velocity of the fragments of the steel cylinders predicted using the Gurney formula and Gurney velocity obtained from a standard cylinder experiment significantly deviated from the experimental observations. This was caused by the difference in the cylinder density and the load coefficient β. Thus, a modified method and model of the Gurney velocity were proposed, and modification coefficients were obtained via a numerical simulation, which provided a means for a more accurate calculation of the initial velocity of fragments of the steel cylinder. Moreover, further analysis showed that at the same β value, the modified Gurney velocity of the copper cylinder was larger than that of the steel cylinder. The modified Gurney velocity of the same cylinders increased with the increase in the β value. The smaller the β value was, the larger the increase in the ratio was. When β > 0.8, the modified Gurney velocity became constant.
Few-layer hexagonal boron nitride as a shield of brittle materials for cryogenic s-SNOM exploration of phonon polaritons
Authors: Hu Debo , Luo Cheng , Kang Lixing , Liu Mengkun , Dai Qing
Published: April 2022

Surface phonon polaritons (SPhPs) in van der Waals (vdW) materials are of great interest in fundamental and applied research fields. Probing the characteristics of vdW SPhPs at cryogenic temperatures is an essential task for their implementation in low-temperature physics. However, the most commonly used characterization technique of vdW SPhPs—scattering-type scanning near-field optical microscopy (s-SNOM) operating in a tapping mode (an intermittent-contact mode)—can be problematic at low temperatures because the sample being tested may become brittle and fragile. Therefore, high fracture toughness is desired for the samples under intermittent-contact s-SNOM scanning at low temperatures. In this work, by taking α-phase molybdenum trioxide (α-MoO3) as an example, we first confirm the potential surface deterioration induced by tip-sample interactions at low temperatures. Then, we propose to use few-layer hexagonal boron nitride as a mechanically tough yet optically passive cladding layer to enhance the surface stability of α-MoO3. Finally, we demonstrate the validity of our surface reinforcement strategy by probing the previously unexplored temperature dependence of SPhPs within the third Reststrahlen band of α-MoO3. Our method allows a sustained operation of tapping mode s-SNOM at cryogenic temperatures with negligible effect on intrinsic properties of SPhPs.
A 3D finite element model to study the cavitation induced stresses on blood–vessel wall during the ultrasound-only phase of photo-mediated ultrasound therapy
Authors: Singh Rohit , Yang Xinmai
Published: April 2022

Photo-mediated ultrasound therapy (PUT) is a novel technique utilizing synchronized ultrasound and laser to generate enhanced cavitation inside blood vessels. The enhanced cavitation inside blood vessels induces bio-effects, which can result in the removal of micro-vessels and the reduction in local blood perfusion. These bio-effects have the potential to treat neovascularization diseases in the eye, such as age-related macular degeneration and diabetic retinopathy. Currently, PUT is in the preclinical stage, and various PUT studies on in vivo rabbit eye models have shown successful removal of micro-vessels. PUT is completely non-invasive and particle-free as opposed to current clinical treatments such as anti-vascular endothelial growth factor therapy and photodynamic therapy, and it precisely removes micro-vessels without damaging the surrounding tissue, unlike laser photocoagulation therapy. The stresses produced by oscillating bubbles during PUT are responsible for the induced bio-effects in blood vessels. In our previous work, stresses induced during the first phase of PUT due to combined ultrasound and laser irradiation were studied using a 2D model. In this work, stresses induced during the third or last phase of PUT due to ultrasound alone were studied using a 3D finite element method-based numerical model. The results showed that the circumferential and shear stress increased as the bubble moves from the center of the vessel toward the vessel wall with more than a 16 times increase in shear stress from 1.848 to 31.060 kPa as compared to only a 4 times increase in circumferential stress from 211 to 906 kPa for a 2 µm bubble placed inside a 10 µm vessel on the application of 1 MHz ultrasound frequency and 130 kPa amplitude. In addition, the stresses decreased as the bubble was placed in smaller sized vessels with a larger decrease in circumferential stress. The changes in shear stress were found to be more dependent on the bubble–vessel wall distance, and the changes in circumferential stress were more dependent on the bubble oscillation amplitude. Moreover, the bubble shape changed to an ellipsoidal with a higher oscillation amplitude in the vessel’s axial direction as it was moved closer to the vessel wall, and the bubble oscillation amplitude decreased drastically as it was placed in vessels of a smaller size.
Participation of nitrogen impurities in the growth of grown-in oxide precipitates in nitrogen-doped Czochralski silicon
Authors: Zhao Tong , Wu Defan , Lan Wu , Yang Deren , Ma Xiangyang
Published: April 2022

For nitrogen-doped Czochralski (NCZ) silicon, it is well known that nitrogen (N) and oxygen (O) impurities can interact to form nitrogen–oxygen shallow thermal donors (N–O STDs); moreover, the N impurities can be involved into heterogeneous nucleation to facilitate the formation of grown-in oxide precipitates. However, how the N impurities participate in the growth of grown-in oxide precipitates during the post-anneal remains unclear. Besides, the correlation between the formation of N–O STDs and the growth of grown-in oxide precipitates is yet to be revealed. In this work, the effects of pre-anneals at temperatures of 900–1200 °C on the formation of N–O STDs at 650 °C in NCZ silicon have been first investigated. Thus, it has been found that the more significant growth of grown-in oxide precipitates during the pre-anneal, which consumes much more N impurities, leads to forming much fewer N–O STDs. This finding stimulates us to explore the mechanism for the participation of N impurities in the growth of grown-in oxide precipitates. To this end, the capture of N impurities by the oxide precipitates, on the one hand, and the release of N impurities from the oxide precipitates, on the other hand, have been investigated by two systematically constructed experiments. The obtained results enable us to reasonably propose that the N impurities participating in the growth of grown-in oxide precipitates predominately reside at the oxide precipitate/Si interfaces, which reduces the interfacial energies, thus favoring the growth of grown-in oxide precipitates. Such a viewpoint is well supported by the density functional theory calculations. In a word, this work has gained an insight into the mechanism for the participation of N impurities in the growth of grown-in oxide precipitates, starting from exploring the correlation between the formation of N–O STDs and the growth of grown-in oxide precipitates.
Transport and modeling of subgrid-scale turbulent kinetic energy in channel flows
Authors: Inagaki Kazuhiro , Kobayashi Hiromichi
Published: April 2022

To develop a more convenient subgrid-scale (SGS) model that performs well even in coarse grid cases, we investigate the transport and modeling of SGS turbulent kinetic energy (hereafter SGS energy) in turbulent channel flows based on the stabilized mixed model (SMM). In this paper, we try to increase the convenience of the SMM by replacing the modeled transport equation for the SGS energy with an algebraic model. The SMM quantitatively adequately predicts the total turbulent kinetic energy of the direct numerical simulation (DNS) even in coarse grid cases. For both the filtered DNS (fDNS) and large-eddy simulation (LES), the statistically averaged production term balances with the dissipation in the region away from the wall in the SGS energy transport equation. In contrast, we reveal that the correlation coefficient between the production and dissipation terms is high for the modeled transport equation in LES, whereas that for the fDNS is low. Based on the high correlation or local equilibrium between the production and dissipation observed in the LES, we demonstrate the reduction of the SMM into a zero-equation SMM (ZE-SMM). We construct a new damping function based on the grid-scale Kolmogorov length to reproduce the near-wall behavior of the algebraic model for the SGS energy. The ZE-SMM provides quantitatively the same performance as the original SMM that employs the SGS energy transport model. This result suggests that the local equilibrium model for the SGS energy provides the equivalent performance as the transport model in wall-bounded turbulent flows even in coarse grid cases.
Policy mix or policy mess? Impacts of policies on the productive efficiency of the Chinese wind power industry
Authors: Shi Jiarong , Jiang Zihao
Published: April 2022

Grand societal challenges call for a sustainability transition away from a fossil-based society toward a low-carbon society. Wind power is highly valued in China, owing to its strong environmental benefits and abundant reserves. Although accelerating the development of wind power industry is near the top of the agenda of the Chinese government, the impact of policies and their mixes on the productive efficiency of the wind power industry is still unclear. In this study, the productive efficiency of the Chinese wind power industry is systematically evaluated using microdata of 119 listed enterprises from 2006 to 2019. The effects of wind power policies and their mixes on the productive efficiency are then elucidated. The empirical results imply that the overall productive efficiency of the Chinese wind power industry is relatively high but that it fluctuated greatly between 2006 and 2019. Moreover, the effects of Chinese wind power policies and their mixes on productive efficiency are ambiguous. Both economic policy (EP) and regulatory policy (RP) hinder productive efficiency; only soft policy (SP) has a significant positive effect. Furthermore, the policy mixes of EP and RP, EP and SP, and RP and SP have no significant impact, but the policy mix of EP, RP, and SP significantly inhibits the productive efficiency of the Chinese wind power industry, indicating conflictive effects and confusion in the policy mix.
Evaporation of supercritical droplets in an electric field using molecular dynamics simulation
Authors: Liu Lu-Hao , Han Yi-Fan , Wang Qun , Fu Qing-Fei
Published: April 2022

This paper studies the combined impacts of electric field and supercritical environment on the evaporation processes of a water droplet. The effects of electric field (0–1.2 V/Å), background temperature (600–1200 K), and pressure (6–56 MPa) on the droplet evaporation and deformation are considered. Simulation results reveal that water droplets would break out into small droplets, which could merge into a large droplet with relatively large electric field. The electric field also shows a dual impact on the evaporation processes. In particular, the evaporation rate would be accelerated first and then suppressed due to the interactions among these water molecules. This rate is not enlarged obviously with the threshold values of the varied combined fields.
Effect of boundary conditions and n-heptane on methyl decanoate HCCI combustion and emission based on two-stroke diesel engine
Authors: Wang Shiye , Zhang Jundong , Xia Wenwen , Yao Li
Published: April 2022

The initial boundary conditions, combustion, and emission characteristics of methyl decanoate (MD) mixed with different proportions of n-heptane (N-Hep) for homogeneous charge compression ignition (HCCI) are studied in this work. MAN B&W 6S70MC two-stroke diesel engine was used as the engine model of the reactor. The results showed that, when the equivalence ratio is 0.48, the NO emissions in the MD and N-Hep HCCI combustion process decrease with the decrease of the initial temperature. The initial temperature is determined to be 380 K. At the same time, NO emissions decrease with the increase of initial pressure, and the initial pressure is determined to be 1.3 atm. The results also indicate that, at a certain initial temperature, the initial pressure and total mole fraction of fuel, CO2, NOx reaction rates, and emissions are reduced significantly with the increase of N-Hep percentage in MD and N-Hep mixing combustion.
High-speed hyperspectral imaging of ferroelectric domain walls using broadband coherent anti-Stokes Raman scattering
Authors: Reitzig Sven , Hempel Franz , Ratzenberger Julius , Hegarty Peter A. , Amber Zeeshan H. , Buschbeck Robin , Rüsing Michael , Eng Lukas M.
Published: April 2022

Spontaneous Raman spectroscopy (SR) is a versatile method for analysis and visualization of ferroelectric crystal structures, including domain walls. Nevertheless, the necessary acquisition time makes SR impractical for in situ analysis and large scale imaging. In this work, we introduce broadband coherent anti-Stokes Raman spectroscopy (B-CARS) as a high-speed alternative to conventional Raman techniques and demonstrate its benefits for ferroelectric domain wall analysis. Using the example of poled lithium niobate, we compare the spectral output of both techniques in terms of domain wall signatures and imaging capabilities. We extract the Raman-like resonant part of the coherent anti-Stokes signal via a Kramers–Kronig-based phase retrieval algorithm and compare the raw and phase-retrieved signals to SR characteristics. Finally, we propose a mechanism for the observed domain wall signal strength that resembles a Čerenkov-like behavior, in close analogy to domain wall signatures obtained by second-harmonic generation imaging. We, thus, lay here the foundations for future investigations on other poled ferroelectric crystals using B-CARS.
Possibility of observation quantum beat coherent exciton states with time-resolved photoemission
Authors: Chaouachi Nizar , Jaziri Sihem
Published: April 2022

We develop a theoretical study to evaluate the dynamic of the time-resolved photoemission spectrum arising from the dissociation of exciton steady-states 1s, 2s in a monolayer transition metal dichlacogenides. We discuss the dielectric environment effect on the exciton binding energies. Quantum beat signatures in photoemission intensity demonstrate coherent coupling between 1s and 2s excitons. The beating contribution due to excitonic coherence is also discussed. The periodic oscillations arising from coherent superposition states and quantum beats enable exploration of novel coherent phenomena.
A metapopulation approach to identify targets for Wolbachia-based dengue control
Authors: Reyna-Lara A. , Soriano-Paños D. , Arias-Castro J. H. , Martínez H. J. , Gómez-Gardeñes J.
Published: April 2022

Over the last decade, the release of Wolbachia-infected Aedes aegypti into the natural habitat of this mosquito species has become the most sustainable and long-lasting technique to prevent and control vector-borne diseases, such as dengue, zika, or chikungunya. However, the limited resources to generate such mosquitoes and their effective distribution in large areas dominated by the Aedes aegypti vector represent a challenge for policymakers. Here, we introduce a mathematical framework for the spread of dengue in which competition between wild and Wolbachia-infected mosquitoes, the cross-contagion patterns between humans and vectors, the heterogeneous distribution of the human population in different areas, and the mobility flows between them are combined. Our framework allows us to identify the most effective areas for the release of Wolbachia-infected mosquitoes to achieve a large decrease in the global dengue prevalence.
High electron mobility in randomly oriented polycrystalline BaSi2 films formed through radio-frequency sputtering
Authors: Koitabashi Ryota , Kido Kazuki , Hasebe Hayato , Mesuda Masami , Toko Kaoru , Suemasu Takashi
Published: April 2022

Semiconducting barium disilicide (BaSi2) is a promising material for solar cell and thermoelectric applications; hence, high-mobility films are of great importance. In this study, we achieved substantially high electron mobilities exceeding 103 cm2 V−1 s−1 at 300 K in randomly oriented polycrystalline BaSi2 films formed on Si3N4 insulating films at 600 °C through radio-frequency sputtering. The BaSi2 films consisted of small grains (<0.5 µm in diameter), and the electron concentration was in the order of 1015–1016 cm−3. Kelvin probe force microscopy revealed that the root-mean-square surface potential values were lower than 31 mV, indicating that the grain boundaries did not hinder electron transport. The potential barrier height across positively charged cracks on the surface of the BaSi2 films, wherein oxidation proceeded, was as small as 30–40 mV. These results indicate that polycrystalline BaSi2 films/insulating films with high electron mobilities are useful for various electronic device applications.
Thermoelectric coolers for high-power-density 3D electronics heat management
Authors: Nozariasbmarz Amin , Kishore Ravi Anant , Li Wenjie , Zhang Yu , Zheng Luyao , Sanghadasa Mohan , Poudel Bed , Priya Shashank
Published: April 2022

Future advancements in three-dimensional (3D) electronics require robust thermal management methodology. Thermoelectric coolers (TECs) are reliable and solid-state heat pumping devices with high cooling capacity that can meet the requirements of emerging 3D microelectronic devices. Here, we first provide the design of TECs for electronics cooling using a computational model and then experimentally validate the main predictions. Key device parameters such as device thickness, leg density, and contact resistance were studied to understand their influence on the performance of TECs. Our results show that it is possible to achieve high cooling power density through optimization of TE leg height and packing density. Scaling of TECs is shown to provide ultra-high cooling power density.
Theoretical analysis of the long-distance limit of NMR chemical shieldings
Authors: Lang Lucas , Ravera Enrico , Parigi Giacomo , Luchinat Claudio , Neese Frank
Published: April 2022

After some years of controversy, it was recently demonstrated how to obtain the correct long-distance limit [point-dipole approximation (PDA)] of pseudo-contact nuclear magnetic resonance chemical shifts from rigorous first-principles quantum mechanics [Lang et al., J. Phys. Chem. Lett. 11, 8735 (2020)]. This result confirmed the classical Kurland–McGarvey theory. In the present contribution, we elaborate on these results. In particular, we provide a detailed derivation of the PDA both from the Van den Heuvel–Soncini equation for the chemical shielding tensor and from a spin Hamiltonian approximation. Furthermore, we discuss in detail the PDA within the approximate density functional theory and Hartree–Fock theories. In our previous work, we assumed a relatively crude effective nuclear charge approximation for the spin–orbit coupling operator. Here, we overcome this assumption by demonstrating that the derivation is also possible within the fully relativistic Dirac equation and even without the assumption of a specific form for the Hamiltonian. Crucial ingredients for the general derivation are a Hamiltonian that respects gauge invariance, the multipolar gauge, and functional derivatives of the Hamiltonian, where it is possible to identify the first functional derivative with the electron number current density operator. The present work forms an important foundation for future extensions of the Kurland–McGarvey theory beyond the PDA, including induced magnetic quadrupole and higher moments to describe the magnetic hyperfine field.
A simple hydrodynamic-particle method for supersonic rarefied flows
Authors: Liu W. , Shu C. , Teo C. J. , Yuan Z. Y. , Liu Y. Y. , Zhang Z. L.
Published: April 2022

In the practical aerospace industry, the supersonic rarefied effect presents multiscale characteristics from the near-continuum regime to the free molecular regime. In this paper, a simple hydrodynamic-particle method (SHPM) is proposed to efficiently capture the multiscale properties for the supersonic rarefied flow. To combine the conventional computational fluid dynamics solver with the particle-based method, the weights are theoretically derived from the integral solution of the Boltzmann Bhatnagar–Gross–Krook equation. The present numerical method is validated by test cases of supersonic shock wave structure, Sod shock-tube, and supersonic flow around the circular cylinder. Numerical results demonstrate that the SHPM could capture the multiscale properties from the continuum regime to the rarefied regime.
Spectra and structure functions of the temperature and velocity fields in supergravitational thermal turbulence
Authors: Wang Dongpu , Liu Shuang , Zhou Quan , Sun Chao
Published: April 2022

We analyze the power spectra and structure functions (SFs) of the temperature and radial velocity fields, calculated in the radial and azimuthal directions, in annular centrifugal Rayleigh–Bénard convection (ACRBC) for Rayleigh number Ra ∈[108,1011], Prandtl number Pr = 10.7, and inverse Rossby number Ro−1=16 using the spatial data obtained by quasi-two-dimensional direct numerical simulation. Bolgiano and Obukhov-like (BO59-like) scalings for the energy spectrum in both the azimuthal and radial directions and thermal spectrum in the azimuthal direction are observed. The range of BO59-like scaling becomes wider as Ra increases. At Ra=1011, it is found that BO59-like scaling Eu(kr)∼kr−11/5 spans nearly two decades for the energy spectrum calculated in the radial direction. Power-law fittings in the range larger than the Bolgiano scales, the scaling exponents of transverse and longitudinal velocity SFs vs the order coincide with the theoretical prediction of BO59 scaling ζpu=3p/5 basically. The second-order temperature SFs exhibit a gradual transition from the Obukhov–Corrsin behavior at scales smaller than the Bolgiano scales to the BO59 behavior at scales larger than the Bolgiano scales. The slopes from the third to sixth-order temperature SFs are similar, which is similar to classical Rayleigh–Bénard convection and Rayleigh–Taylor turbulence. The probability density functions (p.d.f.) of temperature fluctuations δT/σT reveal the cold plumes are strong and the p.d.f. in different regions at high Ra are similar. The stronger turbulent-mixing and larger centrifugal buoyancy in ACRBC may result in the BO59-like scaling.
Early age–related atrophy of cutaneous lymph nodes precipitates an early functional decline in skin immunity in mice with aging
Authors: Sonar Sandip Ashok , Uhrlaub Jennifer L. , Coplen Christopher P. , Sempowski Gregory D. , Dudakov Jarrod A. , van den Brink Marcel R. M. , LaFleur Bonnie J. , Jergović Mladen , Nikolich-Žugich Janko
Published: April 2022

Significance

Older adults are more vulnerable to infection and less capable of vigorously responding to vaccination. The contribution of peripheral T cell maintenance defects to these processes is incompletely understood. Here, we provide evidence that lymph nodes (LNs), which are critical for naive T (T
N
) cell maintenance and initiation of new immune responses, age asynchronously. Skin-draining LNs undergo early (6 to 9 mo) and deeper LN and spleen late-life (18 mo) atrophy, characterized by reduced ability to maintain T
N
cells, structural and numerical loss of LN stromal cell microenvironments, and reduced immunity to cutaneous vaccination. These results highlight the critical role of age-related LN atrophy in functional immunity and immune homeostasis.
Commentary
Authors: Taguchi Naoko
Published: April 2022

Ariadna Sánchez-Hernández presents five articles that showcase current trends of study abroad research in second language (L2) pragmatics. The study abroad context has attracted a large number of empirical investigations in L2 pragmatics (for a review, see Pérez Vidal & Shively, 2019). The popularity of the study abroad context in pragmatics is understandable when we consider the nature of pragmatic competence. Pragmatic competence involves linguistic knowledge, sociocultural knowledge, and the ability to interact with others appropriately using these knowledge bases (Taguchi, 2017). As such, the study abroad context, which offers opportunities to observe cultural norms and to practice contextually appropriate language use, is a prime site for pragmatic development. In this commentary, I focus on three innovative aspects of study abroad pragmatics research that run across the five studies in this volume: (1) longitudinal research design, (2) technology-enhanced data collection methods, and (3) pre-departure instruction focusing on pragmatics. For each aspect, I present critical reflections and recommendations for future research.