bluuebunny/crossref_metadata_2025 huggingface dataset:
The outcome of expandable titanium mesh implants for the treatment of multi-level vertebral compression fractures caused by multiple myeloma
Authors: Gandham Surya , Islim Abdurrahman , Alhamad Saud , Thambiraj Sathya
Published: April 2021

Background: Painful vertebral compression fractures (VCFs) in myeloma patients severely reduce quality of life. Currently, the International Myeloma Working Group (IMWG) and National Institute of Clinical Excellence NICE advocate the use of either balloon kyphoplasty or vertebroplasty in the management of these fractures. Methods: All patients with VCFs and myeloma who adhered to the IMWG indications for vertebral augmentation were treated with the Osseofix® implant. Visual analogue scores (VAS) and Oswestry disability index (ODI) were taken preoperatively and at least one year following surgery. Cobb angle and implant migration were measured on lateral standing radiographs. Results: Sixteen patients (average age 62, SD = 11.6) consisting of 82 levels (range 3–8) were stabilised with no perioperative complications or revisions at one year. There was an improvement in patient-reported outcomes with the median preoperative VAS of 8.6 (IQR 7.3–10.0) reducing to 3 (IQR 1.0–4.0) after one year (P < 0.001) whilst an average improvement of 31.4 (SD = 19.6) points in the ODI scores was reported (P < 0.001). There was no significant collapse or implant failure at one year with a greater improvement in the VAS/ODI score, when more implants were used (P = 0.049 and 0.008, respectively). The average length of stay was 2.2 days (SD = 1.7). Conclusion: The use of the Osseofix® implant in VCFs caused by multiple myeloma has shown a statistically significant improvement in both pain and outcome scores. There were no complications or significant radiological deterioration of spinal alignment over the course of a year.
Seltene Erkrankungen des Larynx, der Trachea und der Schilddrüse
Authors: Hackenberg Stephan , Kraus Fabian , Scherzad Agmal
Published: April 2021

Der Übersichtsartikel beinhaltet eine Zusammenstellung seltener Erkrankungen von Larynx, Trachea und Schilddrüse. Im Speziellen werden angeborene Fehlbildungen, seltene Formen der entzündlichen Larynxerkrankungen, gutartige und bösartige epitheliale sowie nicht-epitheliale Tumoren, laryngeale und tracheale Manifestationen von Allgemeinerkrankungen und schließlich seltene Erkrankungen der Schilddrüse besprochen. Die einzelnen Kapitel beinhalten eine Übersicht über die Datenlage in der Literatur, das jeweilige klinische Erscheinungsbild, wichtige Stichpunkte zur Diagnostik und zur Therapie und eine abschließende Stellungnahme zur Prognose der Erkrankung. Des Weiteren finden sich Hinweise zu Studienregistern und Selbsthilfegruppen.
Akut erworbene konkomitante Esotropie Typ 2 – eine retrospektive Analyse
Authors: Geiger Hans-Georg , Simonsz-Toth Brigitte , Gerth-Kahlert Christina
Published: April 2021

Hintergrund Akutes erworbenes konkomitantes Einwärtsschielen (acute acquired comitant esotropia, AACE) ist eine seltene Schielform. Es besteht Konsens, dass zu den klinischen Merkmalen des AACE Typ 2 im Kindesalter folgende Merkmale gehören: akuter Schielbeginn im etwa 3. Lebensjahr, relativ großer konkomitanter, nicht akkommodativer Schielwinkel, Hyperopie von maximal 3,0 dpt und eine normale Sensorik. Die Diagnose eines AACE Typ 2 stellt eine dringliche Therapieindikation dar, um einen irreversiblen Verlust des bereits erworbenen binokularen Sehens zu vermeiden. Um die klinischen Charakteristika von AACE Typ 2 zu analysieren, wählten wir folgendes Studiendesign.

Patienten und Methoden Retrospektive Datenanalyse der Patienten, die zwischen Oktober 2011 und September 2019 eine Strabismusoperation aufgrund der Verdachtsdiagnose eines AACE Typ 2 an unserer Klinik erhielten, welche sich auch postoperativ anhand von Stellung und Binokularitätsgrad bestätigen ließ. Analysierte Daten beinhalteten: Alter und Symptome bei Erstuntersuchung, Visus, Refraktion, Brillenkorrektur, Alter bei Operation, Intervall von Erstsymptomatik bis zur Operation, Operationsverfahren, Schielwinkel und Binokularitätsgrad (präoperativ und postoperativ 1 Tag, postoperativ 3 und 12 Monate). Die Analyse wurde durch die kantonale Ethikkommission Zürich genehmigt.

Ergebnisse Daten von 18 Patienten (12 männlich, 6 weiblich) konnten in die Studie eingeschlossen werden mit einer Hyperopie von 1,4 ± 0,6 dpt. Eine Amblyopie lag in 2 Fällen vor. Das Alter bei Operation lag zwischen 2,0 und 11,1 Jahren mit einem Intervall zwischen Erstsymptomatik und der Operation von 0,4 bis 24,6 Monaten. Eine Operation wurde innerhalb von 6 Monaten nach Schielbeginn bei 12/18 Kindern durchgeführt. Der präoperativ gemessene Schielwinkel lag in der Nähe bei 38 ± 10 Prismendioptrien (PD) und reduzierte sich nach 3 und 12 Monaten auf 3 ± 3 PD resp. 2 ± 2 PD. Stereosehen erreichten am 1. operativen Tag 5/18 Kinder, nach 12 Monaten dann 18/18 Kinder.

Schlussfolgerung Die Evaluation unserer Patientengruppe mit postoperativ gesicherter Diagnose AACE Typ 2 zeigt, dass in allen Fällen eine geringe Hyperopie, eine große konkomitante, nicht akkommodative Esotropie bestand und die Prognose zur Wiederherstellung von normaler Stereopsis ausgezeichnet ist. Das Vorliegen einer präoperativen Amblyopie schließt eine Normosensorik nach erfolgter Strabismuskorrektur nicht aus. Eine zeitnahe therapeutische Intervention sollte bei Vorliegen o. g. Charakteristika angestrebt werden.
Comparing Botulinum Toxin Injections with Extraocular Muscle Surgery in Toddlers with Esotropia: A Retrospective Analysis
Authors: Handschin Tristan Michael , Roulez Francoise , Schötzau Andreas , Palmowski-Wolfe Anja
Published: April 2021

Background In toddlers with esotropia, early alignment of the visual axes either with extraocular muscle surgery (EOMS) or botulinum toxin injections (BTIs) into both medial rectus muscles may result in improved depth perception. We compared the outcome of BTIs with EOMS in toddlers in order to gain further insight into the advantages and disadvantages of either method.

Patients and Methods In this retrospective study, our encrypted database was searched for toddlers with esotropia aged 35 months or younger at the time of initial treatment with either BTIs or EOMS and who had a follow-up of at least 2 years. We analyzed the angle of deviation, dose effect (DE), and binocularity as well as the number of interventions.

Results We identified 26 toddlers who received their first treatment for esotropia within the first 35 months of life: 16 with BTIs (9 males, 7 females) and 10 with EOMS (3 males, 7 females). Mean follow-up was considerably longer in the EOMS (87.7 months) than in the BTI group (35.7 months). Age at first intervention was 22.8 months in the BTI and 24.1 months in the EOMS group, and each toddler wore its full cycloplegic refraction. Mean angle at treatment was 41.25 prism diopters (PD) in the BTI compared to 52.9 PD in the EOMS group. The BTI group received an average of 1.68 BTIs, with a mean dosage of 14.5 IU Botox and a mean DE (mDE) of 1.8 PD/IU. In the EOMS group, the average number of surgeries was 1.4, with a mean dosage of 16.85 mm and a mDE of 3.14 PD/mm surgery. Some degree of binocularity could be observed in 9 (56%) of the BTI (5 × Bagolini positive, 2 × 550″, 2 × 220″) and in 4 (40%) of the EOMS group (2 × 3600″, 1 × 550″, 1 × 300″). By the end of the
BTI group follow-up, four toddlers electively underwent EOMS rather than a 3rd BTI (followed by a 3rd BTI in 1), which resulted in the appearance of measurable binocularity in all four (1 × Bagolini positive, 1 × 220″, 1 × 200″, 1 × 60″).

Conclusions Our results show that BTIs are a viable treatment alternative in early esotropia. Even if EOMS is ultimately required, some binocularity may develop as the visual axes are aligned for some time in the sensitive phase owing to the effects of Botox. Moreover, less surgical dosage is needed than would have otherwise been necessary to treat the original angle of deviation. BTIs are faster, less invasive, and present as an effective alternative when patient compliance is too low to reliably measure the angle of deviation, which is essential for the planning of EOMS.
Body Mass and Body Composition Changes over 7 Years in a Male
Professional Rugby Union Team
Authors: McHugh Clíodhna , Hind Karen , O'Halloran Aoife , Davey Daniel , Farrell Gareth , Wilson Fiona
Published: April 2021

The purpose of this study was to investigate longitudinal body mass and body
composition changes in one professional rugby union team (n=123),
(i) according to position [forwards (n=58) versus backs
(n=65)], analysis of players with 6 consecutive seasons of DXA scans
(n=21) and, (iii) to examine differences by playing status [academy
and international], over 7 years. Players [mean age: 26.8 y, body
mass index: 28.9+kg.m2] received DXA scans at fourtime
points within each year. A modest (but non-significant) increase in mean
total mass (0.8 kg) for professional players was reflected by
increased lean mass and reduced body fat mass. At all-time points, forwards
had a significantly greater total mass, lean mass and body fat percentage
compared to backs (p<0.05). Academy players demonstrated increased
total and lean mass and decreased body fat percentage over the first 3 years
of senior rugby, although this was not significant. Senior and academy
international players had greater lean mass and lower body fat percentage
(p<0.05) than non-international counterparts. Despite modest
increases in total mass; reflected by increased lean mass and reduced fat
mass, no significant changes in body mass or body composition, irrespective
of playing position were apparent over 7 years.
Drug-Induced Pseudo-Central Serous Chorioretinopathy in Carcinoma Patients
Authors: Jung Sascha Mathias , Valmaggia Christophe , Jörger Markus , Todorova Margarita
Published: April 2021

Purpose Patients with carcinomas often share symptoms of vision deterioration as part of paraneoplastic retinopathy (PNR), based on a cross-reaction between antigens expressed by the underlying tumor and retinal proteins. However, some of the underlying symptoms may be explained by a drug-induced toxicity. The application of new therapeutic strategies with mitogen-activated protein kinase (MEK) and fibroblast growth factor receptor (FGFR) inhibitors in advanced cancers are still under evaluation for safety and tolerability, but also for dose-limiting toxicities. In the presented data, we identified a drug-induced pseudo-central serous chorioretinopathy (pCSC) to be the reason for central vision deterioration.

Methods A retrospective, observational, case-controlled study included seven patients receiving MEK and six patients receiving FGFR inhibitor treatment for bronchopulmonal cancer. We compared the clinical and diagnostic pictures of pCSC patients with that of 50 CSC patients (100 eyes) and 7 patients (14 eyes) with PNR. The activity of pCSC was assessed by clinical examination, supported by multimodal imaging. The relationships between clinical symptomatology and systemic disease activity were evaluated.

Results Three out of thirteen patients (23.1%) showed signs of pCSC (one FGFR and two MEK inhibitor patients). All three pCSC patients showed central bilateral detachment of the neurosensory retina on OCT imaging, but also paracentral multifocal lesions in the second subject. Compared to our CSC and PNR patients, the lesions in pCSC patients showed no lipofuscin irregularities on FAF. With reduction of the MEK treatment, the lesions on one MEK subject disappeared and BCVA restored to 0.8. In one MEK- and the FGFR subject, the lesions reduced in size without therapy discontinuation.

Conclusion Based on our data, MEK and FGFR inhibitor-associated pCSC is a mild, self-limited retinopathy that seems to disappear simultaneously or shortly after discontinuation of medication, with subsequent restoration of the central visual function.
Visual Outcomes after Anti-VEGF Therapy for Exudative Age-Related Macular Degeneration in a Real-Life Setting
Authors: Wenkstern Andrea R. , Valmaggia Christophe
Published: April 2021

Background To report visual outcomes of anti-vascular endothelial growth factor (anti-VEGF) therapy for exudative age-related macular degeneration (AMD) in a real-life setting.

Patients and Methods Retrospective case series of consecutive patients treated with either ranibizumab and/or aflibercept for monolateral or bilateral exudative AMD. A physician established the indication for treatment and administered the injections. An independent physician confirmed the indication for primary treatment. A Pro Re Nata and a Treat and Extend regimen were used. Assessment of subretinal and/or intraretinal fluid, retinal hemorrhage and increase in pigment epithelial detachment served as criteria for further treatment decisions. Visual acuity (VA) was measured in ETDRS letters at each examination and then analyzed using a specialized software. Evolution of mean VA was considered for all study eyes and subgroups of eyes with an initial VA ≥ 70 ETDRS letters (subgroup 1) and ≤ 69 ETDRS letters (subgroup 2).

Results A total of 102 eyes of 76 patients (30 men, mean age 75.9 years; 46 women, mean age 81.5 years) were included. Subgroup 1 consisted of 47 eyes, and subgroup 2 of 55 eyes. Mean follow-up was 55 months (range 6 to 150 months). For the entire collective as for subgroups 1 and 2, the mean VA was 64, 77, or 51 ETDRS letters at baseline. Mean VA improved at month 12 (68, 80, or 58 ETDRES letters) and then slowly decreased over time until month 150 (62, 72, or 54 ETDRS letters). Maximum improvement of + 5, + 3, or, + 9 ETDRS letters occurred after 9, 8, or 10 months of follow-up. Atrophy and fibrosis were mainly responsible for VA decrease. Ten serious adverse events were reported to Swissmedic: two cases of cardiovascular events and eight cases of intraocular inflammation.

Conclusions Anti-VEGF therapy carried out in a real-life setting shows good VA outcomes with a favorable safety profile.
Surgical Outcomes of Gonioscopy-Assisted Transluminal Trabeculotomy (GATT) in Patients with Open-Angle Glaucoma – A Retrospective Case Series
Authors: Vez Sarah , Müller Luzia , Bochmann Frank
Published: April 2021

Purpose To evaluate the outcome of gonioscopy-assisted transluminal trabeculotomy (GATT) in patients with open-angle glaucoma (OAG).

Participants and Methods A retrospective case series of patients with uncontrolled OAG treated by GATT at the cantonal Hospital Lucerne, a tertiary referral center, between October 2018 and July 2019 with a minimal 6-month follow-up period. Main outcome measures were intraocular pressure (IOP), number of antiglaucoma medications, and complications.

Results Thirty-one eyes of 29 patients with a mean age of 70.9 years and a minimal follow-up period of 6 months were included in this study. Twenty eyes were treated for pseudoexfoliation (64.5%), seven for primary open-angle (22.6%), three for pigmentary (9.7%), and one for traumatic (3.2%) glaucoma. Twenty-six eyes had data at the 6-month follow-up and 12 eyes at the 12-month follow-up. Twenty-two eyes (70.9%) were pseudophakic prior to the operation. Mean preoperative IOP was 33 mmHg (standard deviation [SD] 8.0 mmHg). The postoperative IOP was 13.9 mmHg [SD 2.2] at the 6- and 13.9 mmHg [SD 3.1] at the 12-month follow-up. The postoperative IOP evolution translated into a 58% decrease between 6 and 12 months (p < 0.001). Thirteen patients (41.9%) were treated with oral Diamox prior to GATT. The number of antiglaucoma medications decreased from a preoperative average of 2.9 [SD 1.2] to postoperative 1 [SD 1] drug (p < 0.001). The most frequent adverse event
was the occurrence of postoperative hyphema. Hyphema was observed in 21 (68.0%), 7 (22.6%), and 2 (6.4%) eyes at days 1, 7, and 30 after GATT, respectively. Intraocular hypertension over 25 mmHg was seen in eight eyes (25.8%), and in four of them, a steroid response was suspected. One patient developed an anterior uveitis and a macular edema.

Conclusion GATT is an effective and safe intervention for OAG, particularly in pseudoexfoliation glaucoma (PEX). The advantages of GATT compared to filtration surgery are the low rate of long-term complications and that the intervention is feasible even when difficult conjunctival conditions are encountered.
Prospektive Kohortenstudie bei stationären augenchirurgischen Patienten für die Validierung der ClassIntra-Klassifikation für unerwünschte intraoperative Ereignisse
Authors: Hasler Pascal W. , Dell-Kuster Salome , Bossong Olga , Goldblum David , Schartau Pamela Jutta , Wellner Franziska , Rosenthal Rachel , Steiner Luzius A.
Published: April 2021

Hintergrund Gemäß unserer Literaturrecherche gibt es kein validiertes System für die standardisierte Erfassung von unerwünschten intraoperativen Ereignissen (iAEs) in der Augenchirurgie. ClassIntra wurde neu entwickelt, um chirurgie- oder anästhesiebezogene Abweichungen vom idealen intraoperativen Verlauf zu klassifizieren. Ziel der Studie ist die Validierung und die Praktikabilitätserfassung von ClassIntra in der Augenchirurgie.

Methoden In diese prospektive, monozentrische Kohortenstudie wurden nur stationäre, augenchirurgische Patienten eingeschlossen. Die iAEs wurden gemäß ClassIntra klassifiziert und entsprechend den therapeutischen Konsequenzen und den Symptomen des Patienten in 5 Schweregrade unterteilt. Ein 2-wöchiges Follow-up wurde durchgeführt, um alle postoperativen Komplikationen gemäß der Clavien-Dindo-Klassifikation zu erfassen. Primärer Endpunkt war die risikokorrigierte Assoziation zwischen dem schwersten ClassIntra-Grad und der Summe aller postoperativen Komplikationen (Comprehensive Complication Index, CCI) innerhalb des Follow-ups. Außerdem wurden Ophthalmologen und Anästhesisten gebeten, einen Onlinefragebogen auszufüllen, der eine Zuordnung der 5 ClassIntra-Schweregrade zu 10 fiktiven klinischen Fallszenarien erforderte. Die Reliabilität wurde durch den Vergleich der Bewertungen durch die Kliniker mit den vordefinierten Bewertungen des Studienteams geschätzt.

Ergebnisse Es wurden 100 stationäre Patienten im mittleren Alter von 64 Jahren (SA 15) eingeschlossen. Die Mehrheit der Patienten waren ASA II (n = 53, 53%) oder ASA III (n = 42, 42%). Es wurden 32 iAEs in 22 Patienten erfasst (17 × Grad I, 12 × Grad II, 3 × Grad III). Postoperativ traten 94 Komplikationen in 50 Patienten auf (44 × Grad I, 36 × Grad II, 14 × Grad IIIa). Für den primären Endpunkt zeigte sich eine mittlere Differenz im CCI von 2,1 (95%-Konfidenzintervall [KI] − 2,5 – 6,8) pro Zunahme im ClassIntra-Schweregrad. 50 Ophthalmologen und Anästhesisten haben den Onlinefragebogen vollständig ausgefüllt (Antwortrate 54%). Der Intraklassenkorrelationskoeffizient betrug 0,79 (95%-KI 0,64 – 0,94).

Schlussfolgerung Die Anwendung von ClassIntra während der täglichen Routine in der Augenchirurgie erwies sich als praktikables Tool, um iAEs standardisiert zu erfassen. Obwohl sich die Konstruktvalidität nicht nachweisen ließ, unterstreicht die hohe Kongruenz der Umfrageergebnisse eine gute Handhabung der neu entwickelten Klassifikation auch in der Augenchirurgie.
Comparison of All Arthroscopic Implantation of Chitosan-Based Liquid Scaffold and Hyaluronan-Based Soft Scaffold in the Treatment of Condylar Osteochondral Lesions in the Knee
Authors: Akmeşe Ramazan , Özbek Emre Anıl , Kocaoğlu Hakan , Ertan Mehmet Batu , İnanç İrem , Erdemli Esra
Published: April 2021

Cell-free scaffolds used in cartilage regeneration are produced from different materials. The aim of this study is to compare the clinical and radiological results of two different scaffolds with hyaluronan- or chitosan-based structure used in the treatment of symptomatic condylar osteochondral lesions. The study comprises 69 patients who were operated for osteochondral lesion repair with hyaluronan- (n = 37) or chitosan-based (n = 32) scaffold. The International Knee Documentation Committee (IKDC), Lysholm Knee Scoring Scale and Visual Analog Scale (VAS) scores were collected for both groups at the preoperative and postoperative 3rd, 12th, and 24th months. Magnetic resonance imaging was performed between the 12th and 15th months postoperatively and this with magnetic resonance observation of cartilage repair tissue (MOCART) scoring were compared. Within group assessments demonstrate significant improvement in IKDC, Lysholm, and VAS scores at postoperative 3rd and 12th months. However, in both groups, IKDC, Lysholm and, VAS scores at the postoperative 24th month indicate no significant further improvement, compared with the 12th month results. There was no significant difference between the groups in terms of IKDC, Lysholm, VAS, and MOCART scores at any time period. This study shows that both scaffolds are useful in cartilage regeneration but have no clinical or radiological superiority to each other. Surgeons should select the method with which they feel comfortable. This is a level III, retrospective comparative study.
Blick ins Ausland: Kammer ja oder nein – das ist hier die Frage
Authors: Heeser Alexandra
Published: April 2021

Sicherlich ist der Pflegenotstand heute auch Dank der viel beachteten TV-Dokumentation, die Joko und Klaas am 31. März für den Sender ProSieben (siehe Seite 28) produzierten, bekannt und geht durch den Hashtag #nichtselbstverständlich viral.
Psychische Gesundheit: Pollmächer an der Spitze der DGPPN
Authors: Hesser Alexandra
Published: April 2021

Seit zwei Jahren sitzt er mit im Boot. Vor drei Monaten hat Professor Thomas Pollmächer nun das Ruder selbst in die Hand genommen und steht als aktueller Präsident an der Spitze der größten medizinisch-wissenschaftlichen Fachgesellschaft im Bereich der psychischen Gesundheit, der DGPPN. kma spricht mit dem Mediziner unter anderem über die bereits früh veröffentlichten Forderungen der DGPPN zur Bundestagswahl.
A comparison of the chemical bonding and reactivity of Si8H8O12 and Ge8H8O12: A theoretical study
Authors: Muya Jules Tshishimbi , Donald Kelling J. , Ceulemans Arnout , Parish Carol
Published: April 2021

We have analyzed the chemical bonding and reactivity in the cubic molecule octahydridosilsesquioxane, Si8H8O12, and its counterpart Ge8H8O12 by means of ab initio quantum chemical methods and group theory. Density functional theory and MP2 methods combined with the basis sets 6-311+G(d) and 6-311++G(2d,p) were used for geometry optimization and vibrational frequency analysis. The geometries of Si8H8O12 and Ge8H8O12 are unstable under Oh symmetry and distort to the rare Th molecular symmetry. The energy gained from this pseudo-Jahn–Teller distortion ranges from 0.78 to 6.14 kcal mol−1 depending on methodological treatment. The Fukui functions and the molecular electrostatic potential were both used as DFT-based reactivity descriptors. Our study shows that Si8H8O12 and Ge8H8O12 are both hard amphoteric molecules. The cavity within each cage is acidic and able to encapsulate hard small bases such as F−. The exterior of the cages is basic and can form stable exohedral complexes with hard acids, as in the case of H+. The insertion of F− in Si8H8O12 and Ge8H8O12 cages gives the most stable endohedral complexes of the series studied, characterized by formation energies of −3.50 and −3.45 eV at CAM-B3LYP/6-311+G(d) and −3.61 and −3.68 eV at the MP2/6-311++G(d,p) level, respectively. The calculated formation energies of the exohedral and endohedral complexes align with the DFT reactivity descriptor analysis.
Teaching the incompressible Navier–Stokes equations to fast neural surrogate models in three dimensions
Authors: Wandel Nils , Weinmann Michael , Klein Reinhard
Published: April 2021

Physically plausible fluid simulations play an important role in modern computer graphics and engineering. However, in order to achieve real-time performance, computational speed needs to be traded-off with physical accuracy. Surrogate fluid models based on neural networks (NN) have the potential to achieve both fast fluid simulations and high physical accuracy. However, these approaches rely on massive amounts of training data, require complex pipelines for training and inference, or do not generalize to new fluid domains. In this work, we present significant extensions to a recently proposed deep learning framework, which addresses the aforementioned challenges in two dimensions (2D). We go from 2D to three dimensions (3D) and propose an efficient architecture to cope with the high demands of 3D grids in terms of memory and computational complexity. Furthermore, we condition the neural fluid model on additional information about the fluid's viscosity and density, which allows for simulating laminar as well as turbulent flows based on the same surrogate model. Our method allows us to train fluid models without requiring fluid simulation data beforehand. Inference is fast and simple, as the fluid model directly maps a fluid state and boundary conditions at a moment t to a subsequent fluid state at t + dt. We obtain real-time fluid simulations on a 128 × 64 × 64 grid that include various fluid phenomena such as the Magnus effect or Kármán vortex streets and generalize to domain geometries not considered during training. Our method indicates strong improvements in terms of accuracy, speed, and generalization capabilities over current 3D NN-based fluid models.
Domains and domain dynamics in fluorite-structured ferroelectrics
Authors: Lee Dong Hyun , Lee Younghwan , Yang Kun , Park Ju Yong , Kim Se Hyun , Reddy Pothala Reddi Sekhar , Materano Monica , Mulaosmanovic Halid , Mikolajick Thomas , Jones Jacob L. , Schroeder Uwe , Park Min Hyuk
Published: April 2021

Ferroelectricity in fluorite-structured ferroelectrics such as HfO2 and ZrO2 has been attracting increasing interest since its first publication in 2011. Fluorite-structured ferroelectrics are considered to be promising for semiconductor devices because of their compatibility with the complementary metal–oxide–semiconductor technology and scalability for highly dense information storage. The research on fluorite-structured ferroelectrics during the first decade of their conceptualization has been mainly focused on elucidating the origin of their ferroelectricity and improving the performance of electronic devices based on such ferroelectrics. Furthermore, as is known, to achieve optimal performance, the emerging biomimicking electronic devices as well as conventional semiconductor devices based on the classical von Neumann architecture require high operating speed, sufficient reliability, and multilevel data storage. Nanoscale electronic devices with fluorite-structured ferroelectrics serve as candidates for these device systems and, thus, have been intensively studied primarily because in ferroelectric materials the switching speed, reliability, and multilevel polarizability are known to be strongly correlated with the domains and domain dynamics. Although there have been important theoretical and experimental studies related to domains and domain dynamics in fluorite-structured ferroelectrics, they are yet to be comprehensively reviewed. Therefore, to provide a strong foundation for research in this field, herein, domains, domain dynamics, and emerging applications, particularly in neuromorphic computing, of fluorite-structured ferroelectrics are comprehensively reviewed based on the existing literature.
Addressing the symmetry of a converging cylindrical shock wave in water close to implosion
Authors: Rososhek A. , Nouzman D. , Krasik Ya. E.
Published: April 2021

We report experimental and numerical results relevant to the dynamics in the vicinity of the implosion axis of a strong shock wave generated by an underwater electrical explosion of a cylindrical array. Experiments were conducted using both sub-microsecond and microsecond timescale pulsed generators with stored energy up to ∼5 kJ, delivering ∼420/350 kA with a 320/1000 ns rise time pulses to the array, respectively. The backlighted images of the converging shock wave and the light emission around the cylindrical axis indicate strongly that the shock wave front keeps its azimuthal uniformity as far as r ≈30 μm. Also, images obtained almost simultaneously with the implosion suggest symmetric convergence <2 ns prior to the shockwave's arrival to the axis. In addition, the light emission obtained by a photo-multiplying tube suggests the existence of a ∼200 ns long, almost constant, strong afterglow immediately following the light emission peak related to the implosion.
Threshold accumulation of a constitutive protein explains
E. coli
cell-division behavior in nutrient upshifts
Authors: Panlilio Mia , Grilli Jacopo , Tallarico Giorgio , Iuliani Ilaria , Sclavi Bianca , Cicuta Pietro , Cosentino Lagomarsino Marco
Published: April 2021

Significance

The mechanism leading to cell division in the bacterium
Escherichia coli
is unknown, but we know that it results in adding a roughly constant size every cell cycle, regardless of size at birth. While most available studies try to infer information on cell division from steadily dividing cells in constant nutrient conditions, this study leverages a high-resolution device to monitor single-cell growth division upon nutrient changes. Comparing these data with different mathematical models, we are able to discriminate among fundamentally different mechanisms of cell-division control, and we show that the data support a model where an unregulated protein accumulates to a threshold and triggers division.
Essential role of papillae flexibility in nectar capture by bees
Authors: Lechantre Amandine , Draux Ayrton , Hua Hoa-Ai Béatrice , Michez Denis , Damman Pascal , Brau Fabian
Published: April 2021

Significance

Flowers provide the energy resources of bees. In a competitive world, we can hypothesize that flowers attract bees by producing very sweet nectar since it offers the greatest energetic rewards. However, the nectar sugar concentration rarely exceed 60%, and in vivo measurements show that bees capture nectar less efficiently beyond that limit. Here, we explain the physiological origin of this limit based on an elastoviscous mechanism. Most of bees collect the nectar with tongues covered by elongated papillae that open when immersed in a fluid, the opening dynamics determining the amount of nectar collected per lap. At very large sugar concentrations, we found that viscous forces impede the full opening of papillae, reducing the amount of nectar collected.
PLCγ1 promotes phase separation of T cell signaling components
Authors: Zeng Longhui , Palaia Ivan , Šarić Anđela , Su Xiaolei
Published: April 2021

The T cell receptor (TCR) pathway receives, processes, and amplifies the signal from pathogenic antigens to the activation of T cells. Although major components in this pathway have been identified, the knowledge on how individual components cooperate to effectively transduce signals remains limited. Phase separation emerges as a biophysical principle in organizing signaling molecules into liquid-like condensates. Here, we report that phospholipase Cγ1 (PLCγ1) promotes phase separation of LAT, a key adaptor protein in the TCR pathway. PLCγ1 directly cross-links LAT through its two SH2 domains. PLCγ1 also protects LAT from dephosphorylation by the phosphatase CD45 and promotes LAT-dependent ERK activation and SLP76 phosphorylation. Intriguingly, a nonmonotonic effect of PLCγ1 on LAT clustering was discovered. Computer simulations, based on patchy particles, revealed how the cluster size is regulated by protein compositions. Together, these results define a critical function of PLCγ1 in promoting phase separation of the LAT complex and TCR signal transduction.
Infrared Cancellation and Measurement
Authors: Miller Michael E.
Published: April 2021

Quantum field theories containing massless particles are divergent not just in the ultraviolet but also in the infrared. Infrared divergences are typically regarded as less conceptually problematic than ultraviolet divergences because there is a cancellation mechanism that renders measurable physical observables such as decay rates and cross-sections infrared finite. In this article, I scrutinize the restriction to measurable physical observables that is required to arrive at infrared finite results. I argue that the restriction does not necessitate a retreat to operationalism about the meaning of the theory, but it does call attention to underappreciated features of the infrared regime.
Fully pseudospectral solution of the conformally invariant wave equation on a Kerr background
Authors: Hennig Jörg , Macedo Rodrigo Panosso
Published: April 2021

We study axisymmetric solution to the conformally invariant wave equation on a Kerr background by means of numerical and analytical methods. Our main focus is on the behaviour of the solutions near spacelike infinity, which is appropriately represented as a cylinder. Earlier studies of the wave equation on a Schwarzschild background have revealed important details about the regularity of the corresponding solutions. It was found that, on the cylinder, the solutions generically develop logarithmic singularities at infinitely many orders. Moreover, these singularities also ‘spread’ to future null infinity. However, by imposing certain regularity conditions on the initial data, the lowest-order singularities can be removed. Here we are interested in a generalisation of these results to a rotating black hole background and study the influence of the rotation rate on the properties of the solutions. To this aim, we first construct a conformal compactification of the Kerr solution which yields a suitable representation of the cylinder at spatial infinity. Besides analytical investigations on the cylinder, we numerically solve the wave equation with a fully pseudospectral method, which allows us to obtain highly accurate numerical solutions. This is crucial for a detailed analysis of the regularity of the solutions. In the Schwarzschild case, the numerical problem could effectively be reduced to solving (1 + 1)-dimensional equations. Here we present a code that can perform the full 2 + 1 evolution as required for axisymmetric waves on a Kerr background.
Quantum mechanics for non-inertial reference frames
Authors: Moreno M , del Río J A
Published: April 2021

In quantum mechanics courses, the concept of a reference frame is frequently hidden. In this article, we present a basic perspective to introduce the transformations of a reference frame based on unitary transformations. These unitary transformations are inspired in canonical transformation for reference frame from the perspective of classical mechanics. The manner we deal with this change in reference frame allows us to discuss some fundamental concepts in Schrödinger and Heisenberg pictures, as well as the ideas of passive and active description in quantum mechanics. These unitary transformations are inspired in a reference-frame canonical transformation from the perspective of classical mechanics. The approach we take for this reference-frame change allows for a discussion on fundamental concepts in Schrödinger and Heisenberg pictures, as well as the ideas of passive and active description in quantum mechanics. We apply this unitary transformation in five examples.
Flexible low-voltage organic thin-film transistors and PMOS inverters: the effect of channel width on noise margin
Authors: Singh Subhash , Matsui Hiroyuki , Tokito Shizuo
Published: April 2021

Low-operating-voltage (<2 V) organic thin-film transistors (OTFTs) and P-channel metal-oxide-semiconductor (PMOS) inverter circuits are fabricated on a 125 µm-thick flexible polyethylene naphthalate substrate using a blend of 2,7-dihexyl-dithieno[2,3-d;2′,3′-d′]benzo[1,2-b;4,5-b′]dithiophene and polystyrene as an active p-type organic semiconducting material. All three electrodes (gate, source, and drain) are inkjet-printed, while the active semiconducting material is deposited by a dispenser system to achieve a saturation mobility of 0.32 cm2 V−1 s−1 at V
GS = −2 V. Two different PMOS inverters are fabricated, for which the signal gain peak values are resolved for an ultra-low supply voltage, V
DD = −0.5 V. We achieve a signal gain of 2.73 at V
DD = −0.5 V. The effect of channel width is demonstrated for both OTFTs and PMOS devices. The ‘on’ current increases with channel width, and the switching point of the PMOS inverters shifts toward the middle of the voltage transfer characteristics, and hence improves the noise margin.
Operando 3D imaging of defects dynamics of twinned-nanocrystal during catalysis
Authors: Meneau Florian , Rochet Amélie , Harder Ross , Cha Wonsuk , Ribeiro Passos Aline
Published: April 2021

Using operando Bragg coherent x-ray diffraction imaging, we visualised three-dimensionally a single twinned-gold nanocrystal during the CO oxidation reaction. We describe the defect dynamics process occurring under operating conditions and indicate the correlation between the nucleation of highly strained regions at the surface of the nanocrystal and its catalytic activity. Understanding the twinning deformation mechanism sheds light on the creation of active sites, and could well contribute to the understanding of the catalytic behaviour of other catalysts. With the start-up of 4th generation synchrotron sources, we anticipate that coherent hard x-ray diffraction imaging techniques will play a major role in imaging in situ chemical processes.
Current distribution and group velocities for electronic states on

α−T3

lattice ribbons in a magnetic field
Authors: Oriekhov D O , Voronov Sergey
Published: April 2021

We study the group velocities of electronic states and distributions of currents in

α
−

T

3

lattice ribbons under a uniform perpendicular magnetic field. Using the effective low-energy model we analyze all possible simple configurations of lattice termination with zigzag and armchair boundaries. We show that the edge current depends on the type of zigzag termination, and can be zero or finite near the edge. Also similar dependence is observed in the case of armchair termination and is related to the size of the ribbon. The nonzero current flowing along the edge can be used a signature of formation of propagating edge states. In addition, we show the qualitative difference in the distribution of the edge current between the case of α = 1 (dice model) and other values of model parameter α ≠ 1 for armchair-terminated ribbons.
Effect of temperature and humidity on the sensing performance of TiO2 nanowire-based ethanol vapor sensors
Authors: Shooshtari Mostafa , Salehi Alireza , Vollebregt Sten
Published: April 2021

In this paper, we study the influence of two key factors, temperature, and humidity, on gas sensors based on titanium dioxide nanowires synthesized at 4 different temperatures and with different morphology. The samples’ structure are investigated using SEM, XRD and FTIR analysis. The effects of humidity and temperature are studied by measuring the resistance and gas response when exposed to ethanol. At room temperature, we observed a 15% sensitivity response to 100 ppm of ethanol vapor and by increasing the operating temperature up to 180 °C, the response is enhanced by two orders of magnitude. The best operating temperature for the highest gas response is found to be around 180 °C. Also, it was observed that every nanowire morphology has its own optimum operating temperature. The resistance of sensors is increased at higher Relative Humidity (RH). Besides, the response to ethanol vapor experiences a gradual increase when the RH rises from 10% to 60%. On the other hand, from 60% to 90% RH the gas response decreases gradually due to different mechanisms of interaction of the TiO2 with H2O and ethanol molecules.
Improvement of electron beam quality in laser wakefield acceleration by a circularly-polarized laser pulse
Authors: Jain A , Gupta D N
Published: April 2021

Electron acceleration driven by laser wakefield using a laser pulse with circular polarization is studied to generate better-quality electron bunches. In order to inject electrons into the accelerating phase of the plasma wave, a density transition shaped bump is employed. Using particle-in-cell simulations, we demonstrate the influence of laser polarization on the quality of electron bunch. The simulation results (using experimentally achievable parameters) show that the electron bunch with higher peak-energy, narrow energy-spread, and low emittance can be obtained by using a laser pulse with circular polarization as compared to the usually employed linear polarization in a mm-scale length plasma. The results show the improved quality of the electron bunch generated from laser wakefield accelerations. The predicted electron bunch quality may be crucial in developing plasma-based electromagnetic radiation sources.
Quantum Langevin approach for superradiant nanolasers
Authors: Protsenko Igor E , Uskov Alexander V , André Emil C , Mørk Jesper , Wubs Martijn
Published: April 2021

A new approach for analytically solving quantum nonlinear Langevin equations is proposed and applied to calculations of spectra of superradiant lasers where collective effects play an important role. We calculate lasing spectra for arbitrary pump rates and recover well-known results such as the pump dependence of the laser linewidth across the threshold region. We predict new sideband peaks in the spectrum of superradiant lasers with large relaxation oscillations as well as new nonlinear structures in the lasing spectra for weak pump rates. Our approach sheds new light on the importance of population fluctuations in the narrowing of the laser linewidth, in the structure of the lasing spectrum, and in the transition to coherent operation.
Free-electron nanolaser based on graphene plasmons
Authors: Avetissian H K , Avchyan B R , Matevosyan H H , Mkrtchian G F
Published: April 2021

In this paper, a possible way to achieve lasing from the THz to the extreme UV domain due to stimulated scattering of graphene plasmons (GPs) on free electrons is considered. The analytical-quantitative description of the proposed free electron laser scheme is based on a self-consistent set of Maxwell–Vlasov equations. We study the downconversion as well as the upconversion. It is shown that the coherent downconversion of infrared radiation to THz can be achieved using a source of very non-relativistic electrons at the resonant coupling with the GPs. Due to the strongly confined GPs, the upconversion of mid-infrared to extreme UV radiation can be achieved with mildly relativistic electron beams. The latter is a promising mechanism for a tabletop short-wavelength free-electron nanolaser.
Study on higher moments of net-charge multiplicity distributions using a multiphase transport model *
Authors: Huang Ling , Ma Guo-Liang
Published: April 2021

The moments and moment products of conserved charges are believed to be sensitive to critical fluctuations, which have been adopted in determining the QCD critical point. Using a dynamical multiphase transport model, we reproduce the centrality and energy dependences of moments and moment products of net-charge multiplicity distributions in Au+Au collisions, measured by the Beam Energy Scan program at the RHIC. No non-monotonic energy dependence is observed. We infer that the moment products develop during the dynamical evolution of heavy-ion collisions. The observed difference based on the expectation of the Poisson baseline indicates a positive two-particle correlation between positively and negatively charged particles, which can arise from different dynamical processes at different stages. Therefore, to adopt moments and moment products of net-charge multiplicity distributions in determining the QCD critical point of relativistic heavy-ion collisions, it is essential to consider the dynamical evolution.
Recent progress in integrated electro-optic frequency comb generation
Authors: Sun Hao , Khalil Mostafa , Wang Zifei , Chen Lawrence R.
Published: April 2021

Optical frequency combs have emerged as an important tool enabling diverse applications from test-and-measurement, including spectroscopy, metrology, precision distance measurement, sensing, as well as optical and microwave waveform synthesis, signal processing, and communications. Several techniques exist to generate optical frequency combs, such as mode-locked lasers, Kerr micro-resonators, and electro-optic modulation. Important characteristics of optical frequency combs include the number of comb lines, their spacing, spectral shape and/or flatness, and intensity noise. While mode-locked lasers and Kerr micro-resonators can be used to obtain a large number of comb lines compared to electro-optic modulation, the latter provides increased flexibility in tuning the comb spacing. For some applications in optical communications and microwave photonics, a high degree of integration may be more desirable over a very large number of comb lines. In this paper, we review recent progress on integrated electro-optic frequency comb generators, including those based on indium phosphide, lithium niobate, and silicon photonics.
Photonic radio frequency channelizers based on Kerr optical micro-combs
Authors: Tan Mengxi , Xu Xingyuan , Wu Jiayang , Nguyen Thach G. , Chu Sai T. , Little Brent E. , Morandotti Roberto , Mitchell Arnan , Moss David J.
Published: April 2021

We review recent work on broadband RF channelizers based on integrated optical frequency Kerr micro-combs combined with passive micro-ring resonator filters, with microcombs having channel spacings of 200 and 49 GHz. This approach to realizing RF channelizers offers reduced complexity, size, and potential cost for a wide range of applications to microwave signal detection.
Hybrid material integration in silicon photonic integrated circuits
Authors: Chakravarty Swapnajit , Teng Min , Safian Reza , Zhuang Leimeng
Published: April 2021

Hybrid integration of III–V and ferroelectric materials is being broadly adopted to enhance functionalities in silicon photonic integrated circuits (PICs). Bonding and transfer printing have been the popular approaches for integration of III–V gain media with silicon PICs. Similar approaches are also being considered for ferroelectrics to enable larger RF modulation bandwidths, higher linearity, lower optical loss integrated optical modulators on chip. In this paper, we review existing integration strategies of III–V materials and present a route towards hybrid integration of both III–V and ferroelectrics on the same chip. We show that adiabatic transformation of the optical mode between hybrid ferroelectric and silicon sections enables efficient transfer of optical modal energies for maximum overlap of the optical mode with the ferroelectric media, similar to approaches adopted to maximize optical overlap with the gain section, thereby reducing lasing thresholds for hybrid III–V integration with silicon PICs. Preliminary designs are presented to enable a foundry compatible hybrid integration route of diverse functionalities on silicon PICs.
Latest advances in high-performance light sources and optical amplifiers on silicon
Authors: Liu Songtao , Khope Akhilesh
Published: April 2021

Efficient light generation and amplification has long been missing on the silicon platform due to its well-known indirect bandgap nature. Driven by the size, weight, power and cost (SWaP-C) requirements, the desire to fully realize integrated silicon electronic and photonic integrated circuits has greatly pushed the effort of realizing high performance on-chip lasers and amplifiers moving forward. Several approaches have been proposed and demonstrated to address this issue. In this paper, a brief overview of recent progress of the high-performance lasers and amplifiers on Si based on different technology is presented. Representative device demonstrations, including ultra-narrow linewidth III–V/Si lasers, fully integrated III–V/Si/Si3N4 lasers, high-channel count mode locked quantum dot (QD) lasers, and high gain QD amplifiers will be covered.