bluuebunny/crossref_metadata_2025 huggingface dataset:
Behandlung einer Femurkopfepiphysenfraktur mittels modifizierter Ehmer-Schlinge bei einem 4 Wochen alten Fleckviehkalb
Authors: Marks Viktoria , Schieder Katrin , Kofler Johann
Published: October 2020

Ein 4 Wochen altes, weibliches Fleckviehkalb wurde mit einer seit 3 Tagen bestehenden, plötzlich aufgetretenen Lahmheit 5. Grades an der rechten Hintergliedmaße vorgestellt. Klinisch war eine schmerzhafte Schwellung im Bereich der rechten Hüftgelenkregion nachweisbar, jedoch keine typischen Fraktursymptome wie Krepitation, abnorme Achsenbrechung und abnorme Beweglichkeit. Bei der sonografischen Untersuchung mit einem 7,5-MHz-Linearschallkopf wurden eine geringgradige Stufenbildung und eine abnorme Beweglichkeit im Bereich der Femurkopfepiphysenfuge festgestellt. Die Röntgenuntersuchung zeigte eine Salter-Harris-Fraktur Typ 2 an der Epiphysenfuge des rechten Femurkopfes. Aufgrund der nur geringgradigen Dislokation von ca. 2 mm nach kranial erfolgte eine konservative Behandlung durch Ruhigstellung der rechten Hintergliedmaße mit einer modifizierten Ehmer-Schlinge, die im Behandlungszeitraum von 28 Tagen 2-mal gewechselt wurde. Das Kalb kam mit der Schlinge gut zurecht und war gehfähig. Mit dieser Behandlung konnte eine vollständige Frakturheilung erzielt und die hohen Kosten und Risiken einer chirurgischen Frakturversorgung vermieden werden. Zehn Wochen nach Therapiebeginn war das Kalb lahmheitsfrei.
Feasibility and safety study of 22-gauge endoscopic ultrasound (EUS) needles for portal vein sampling in a swine model
Authors: Park Kenneth , Lew Daniel , Chapman Christopher , Wachsman Ashley , Bloom Matthew , Bancila Liiana , Perry Rachel , Wang Qiang , Jamil Laith , Pandol Stephen , Lo Simon
Published: October 2020

Background and study aims Endoscopic ultrasound (EUS) has been used for portal vein sampling in patients with pancreaticobiliary cancers for enumerating circulating tumor cells but is not yet a standard procedure. Further evaluation is needed to refine the methodology. Therefore, we evaluated the feasibility and safety of 19-gauge (19G) versus a 22-gauge (22 G) EUS fine-needle aspiration needles for portal vein sampling in a swine model.

Methods Celiotomy was performed on two farm pigs. Portal vein sampling occurred transhepatically. We compared 19 G and 22 G needles coated interiorly with saline, heparin or ethylenediaminetetraacetic acid (EDTA). Small- (10 mL) and large- (25 mL) volume blood collections were evaluated. Two different collection methods were tested: direct-to-vial and suction syringe. A bleeding risk trial for saline-coated 19 G and 22 G needles was performed by puncturing the portal vein 20 times. Persistent bleeding after 3 minutes was considered significant.

Results All small-volume collection trials were successful except for 22 G saline-coated needles with direct-to-vial method. All large-volume collection trials were successful when using suction syringe; direct-to-vial method for both 19 G and 22 G needles were unsuccessful. Collection times were shorter for 19 G vs. 22 G needles for both small and large-volume collections (P < 0.05). Collection times for saline-coated 22 G needles were longer compared to heparin/EDTA-coated (P < 0.05). Bleeding occurred in 10 % punctures with 19 G needles compared to 0 % with 22 G needles.

Conclusion The results of this animal study demonstrate the feasibility and the safety of using 22 G needles for portal vein sampling and can form the basis for a pilot study in patients.
G-protein Coupled Estrogen Receptor Expression in Growth Hormone Secreting and Non-Functioning Adenomas
Authors: Ozkaya Hande Mefkure , Sayitoglu Muge , Comunoglu Nil , Sun Eda , Keskin Fatma Ela , Ozata Duygu , Hocaoglu Rabia Hacer , Khodzaev Khusan , Firtina Sinem , Tanriover Necmettin , Gazioglu Nurperi , Oz Buge , Kadioglu Pinar
Published: October 2020

Purpose To evaluate the expression of G-protein coupled estrogen receptor (GPER1), aromatase, estrogen receptor α (ERα), estrogen receptor β (ERβ), pituitary tumor transforming gene (PTTG), and fibroblast growth factor 2 (FGF2) in GH-secreting and non-functioning adenomas (NFA).

Methods Thirty patients with acromegaly and 27 patients with NFA were included. Gene expression was determined via quantitative reverse transcription polymerase chain reaction (QRT-PCR). Protein expression was determined via immunohistochemistry.

Results There was no difference, in terms of gene expression of aromatase, ERα, PTTG, and FGF2 between the two groups (p>0.05 for all). ERβ gene expression was higher and GPER1 gene expression was lower in GH-secreting adenomas than NFAs (p<0.05 for all). Aromatase and ERβ protein expression was higher in GH-secreting adenomas than NFAs (p=0.01). None of the tumors expressed ERα. GPER1 expression was detected in 62.2% of the GH-secreting adenomas and 45% of NFAs. There was no difference in terms of GPER1, PTTG, FGF2 H scores between the two groups (p>0.05 for all). GPER1 gene expression was positively correlated to ERα, ERβ, PTTG, and FGF2 gene expression (p<0.05 for all). There was a positive correlation between aromatase and GPER1 protein expression (r=0.31; p=0.04).

Conclusions GPER1 is expressed at both gene and protein level in a substantial portion of GH-secreting adenomas and NFAs. The finding of a positive correlation between GPER1 and ERα, ERβ, PTTG, and FGF2 gene expression and aromatase and GPER1 protein expression suggests GPER1 along with aromatase and classical ERs might mediate the effects of estrogen through upregulation of PTTG and FGF2.
Congenital Aortic Vascular Ring: In-Utero Sonographic Assessment of Tracheal Patency and Postnatal Outcome
Authors: Achiron Reuven Ryszard , Kassif Eran , Gilboa Yinon , Salem Yishay , Jakobson Yizhak , Raviv-Zilka Lisa , Kivilevitch Zvi
Published: October 2020

Objective Congenital aortic vascular ring may present after birth with variable degrees of respiratory distress due to tracheal compression. The aim of this study was to prospectively evaluate in utero tracheal patency in correlation with postnatal outcome.

Methods During an eight-year period, fetuses with aortic arch abnormality encircling the trachea and forming a complete ring were recruited for the study. Tracheal patency was classified as: no compression, partial compression, or complete compression. Postnatal MRI/CTangio studies were performed and outcome data was retrospectively analyzed from the medical records.

Results Among the 46 fetuses recruited to the study, 38 had right aortic arch (RAA), and 8 presented with double aortic arch (DAA). In the RAA group 35 (92.1 %) of the fetuses presented no compression and 34 (97.1 %) of them were asymptomatic in the long-term follow-up. Three fetuses (7.9 %) in this group presented in utero compression: one was terminated at 16 weeks of gestation due to associated ominous findings, and the other two had mild respiratory symptoms around 12 months of age and underwent surgery with a good outcome. In the DAA group, all fetuses presented in utero with tracheal compression. Seven showed partial and one complete compression. Among the seven with partial compression, six were symptomatic and underwent surgery. The case with severe airway occlusion had emergency tube insertion in the delivery room and underwent surgery at 7 days but died from severe respiratory complications.

Conclusion This is the first study to evaluate in utero tracheal patency in cases with vascular ring. It allows better prenatal and postnatal workup and follow-up including potentially life-threatening respiratory failure.
Palladium Nanoparticles Anchored on Magnesium Organosilicate: An Effective and Selective Catalyst for the Heck Reaction
Authors: Domingues Nelson Luís C. , dos Santos Beatriz F. , da Silva Beatriz A. L. , de Oliveira Aline R. , Sarragiotto Maria H. , Rinaldi Andrelson W.
Published: October 2020

A new and effective palladium catalyst supported on a magnesium organosilicate for application in the Heck reaction is presented. A group of compounds comprising 22 examples were synthesized in moderate to high yields (up to 99%) within a short time. The palladium supported on magnesium organosilicate catalyst was characterized as an amorphous solid by SEM, containing around 33% of palladium inside the solid, and even with this low quantity of palladium, the catalyst was very efficient in the Heck reaction. Besides, based on the Scherrer equation, the crystallite size of the synthesized palladium nanoparticles was ultrasmall (around 1.3 nm). This strategy is a simple and efficient route for the formation of C–C bonds via the Heck cross-coupling reaction.
Formal [5+3] Cycloaddition between Isatin-Based α-(Trifluoromethyl)imine Ylides and Vinyloxiranes: Diastereoselective Access to Medium-Heterocycle-Fused Spirooxindoles
Authors: Zhao Hong-Wu , Wang Li-Ru , Ding Wan-Qiu , Guo Jia-Ming , Tang Zhe , Song Xiu-Qing , Wu Hui-Hui , Fan Xiao-Zu , Bi Xiao-Fan , Zhong Qi-Di
Published: October 2020

In the presence of Pd2(dba)3·CHCl3 (2.5 mol%), PPh3 (10 mol%), and 60% NaH (1.5 equiv), the formal [5+3] cycloaddition between isatin-based α-(trifluoromethyl)imines and vinyloxiranes proceeded readily in 1,2-DCE at 40 ℃ and afforded cis-configured medium-heterocycle-fused spirooxindoles in the reasonable chemical yields with >20:1 dr. The relative stereochemical configuration of the title products was identified by X-ray diffraction analysis.
Aminocatalytic Synthesis of Uracil Derivatives Bearing a Bicyclo[2.2.2]octane Scaffold via a Doubly Cycloadditive Reaction Cascade
Authors: Albrecht Łukasz , Saktura Maciej , Frankowski Sebastian , Joachim Bartłomiej
Published: October 2020

Aminocatalytic synthesis of highly enantiomerically enriched uracil derivatives bearing a bicyclo[2.2.2]octane scaffold is described. The developed strategy utilizes 1,3,6-trimethyl-5-formyluracil and α,β-unsaturated aldehydes as starting materials and has been realized employing various aminocatalytic activation strategies operating in a synergistic manner. The reaction cascade can be described as doubly cycloadditive as it consists of two consecutive Diels–Alder cycloadditions allowing for a facile construction of the bicyclo[2.2.2]octane scaffold. Notably, both steps proceed with dearomatization of the partially aromatic uracil moiety. Excellent stereoselectivity of the reaction cascade is ensured by the use of 2-(diphenylmethyl)pyrrolidine as aminocatalyst.
Risk Factors for Mortality among Newborns with Neonatal Seizures
Authors: Tanous Osama , Watad Mohamad , Felszer-Fisch Clari , Peniakov Marina , Miron Dan , Salim Raed
Published: October 2020

Objective The aim of the study is to examine the incidence and risk factors for death among neonates who developed neonatal seizures (NS) in an ethnically distinctive community with high consanguinity rate in Israel.

Methods Retrospective study was conducted at a single institution on data between January 2001 and January 2016. All neonates diagnosed with NS developed up to age 28 days were included. Mortality was defined as death within the first year of life.

Results Of all 69,460 neonates born during the study period, 118 (1.7 per 1,000 live births) developed NS; 35 (29.7%) died within the first year while 83 (70.3%) survived. The leading causes of death were developmental brain malformation (31.4%), genetic/metabolic (20%), hypoxic ischemic encephalopathy (20%), intracranial hemorrhage (11.4%) and infections (11.4%). Any consanguinity between the parents was found in 18 and 14.6% among the survivors and deceased groups, respectively (p = 0.24). Developmental brain malformations that lead to death were present in 3.6 and 31.4% in the survivors and deceased groups, respectively (p = 0.001; relative risk 8.70; 95% confidence interval 2.58–29.27). Stepwise backward logistic regression analysis revealed that developmental brain malformations (p < 0.0001), use of more than one antiepileptic medication (p = 0.006), and multiorgan failure (p = 0.004) were significant risk factors that predicted death.

Conclusion The results of the current study show that developmental brain malformations that cause NS were the leading risk factor for death.
Multicenter Experience with Nusinersen Application via an Intrathecal Port and Catheter System in Spinal Muscular Atrophy
Authors: Flotats-Bastardas Marina , Hahn Andreas , Schwartz Oliver , Linsler Steffan , Meyer Sascha , Kolodziej Malgorzata , Koehler Cornelia
Published: October 2020

Nusinersen, an antisense oligonucleotide enhancing the production of the survival motor neuron protein, is approved for the treatment of spinal muscular atrophy (SMA) but requires repetitive lumbar punctures. Application via a subcutaneous port connected to a permanent intrathecal catheter has been proposed as an alternative for patients with severe scoliosis, spinal fusion, or comorbidities, rendering serial interlaminar punctures complicated and risky. Since experience with this technique is sparse and follow-up data are lacking, we assessed feasibility, safety, and tolerability of this approach in eight patients with SMA II/SMA III receiving Nusinersen in a multicenter study. Median age at port implantation was 21 years (range: 10–30 years), and median follow-up time thereafter was 19 months (range: 7–24 months). Leakage of the port catheter occurred in two patients, promptly resolving after resuturing. No further complications such as infection, dislocation, kinking, or obstruction of the port were noted in any of the patients. These findings suggest that application via an intrathecal port and catheter system represents a safe and feasible option for Nusinersen treatment in subjects with SMA. However, to detect rare adverse events longer term follow-up in a larger study cohort is warranted.
Not Just Fat: Imaging in Abdominal Fat Pathology
Authors: Patil Aruna R. , Nandikoor Shrivalli , Jagannath Pramod , Bansal Amit
Published: October 2020

Fat in abdomen has diverse distribution and function. Insult to fat due to several causes can result in infarction or necrosis and present as acute abdomen clinically. Intra-abdominal focal fat infarction is one such condition that comprises of epiploic appendagitis, perigastric appendagitis, omental infarction, and torsion of fatty appendage of falciform ligament that have characteristic imaging features. Secondary causes of fat necrosis include pancreatitis or trauma related. Metabolic or responsive fat changes, like hypertrophy and dystrophy, can be diagnosed on imaging especially on computed tomography. Mesentric fat stranding including the mesentric panniculitis spectrum poses diagnostic dilemma and the causes and imaging role are covered in this review. Some infections and neoplasms that preferably affect abdominal fat compartments may mimic benign conditions, although some have specific patterns of involvement.
Anorectal Malformations and the Risk of Colorectal Cancer—Is Early Routine Endoscopic Screening Indicated?
Authors: Svenningsson Anna , Gunnarsdottir Anna , Wester Tomas
Published: October 2020

Introduction Colorectal cancer (CRC) has been reported in early adulthood in patients with anorectal malformation (ARM), and therefore, the need of endoscopic controls has been discussed. The aim of this study was to assess the risk of CRC in patients with ARM.

Materials and Methods This was a nationwide population-based study with data from Swedish national health care registers. All patients diagnosed with ARM born in Sweden between 1964 and 1999 were identified in the National Patient Register. The same group was followed up in the Swedish Cancer Register from birth to December 31, 2014, for occurrences of CRC. Five age- and gender-matched individuals randomly selected from the Medical Birth Register served as controls for each ARM patient born between 1973 and 1999.

Results A total of 817 patients (474 males) with ARM were included and followed up from birth to the end of observational period. Time of follow-up ranged from 15 to 50 years (mean: 28 years). None of the patients was diagnosed with CRC during the observational period. One case of rectal cancer and one case of sigmoid cancer were detected among the 3,760 controls.

Conclusion In our study, the risk of CRC in early adulthood in patients with ARM is low. Our result does not support routine endoscopic follow-up for patients with ARM during the first decade of life.
The Relationship between Serum Total Bilirubin and Severity of Hypoxic Injury in Neonatal Hypoxic–Ischemic Encephalopathy
Authors: Haga Mitsuhiro , Kawabata Ken , Sumiya Wakako , Kurita Saori , Imanishi Toshiyuki , Kanno Chika , Kanno Masayuki , Kanno Masami , Shimizu Masaki
Published: October 2020

Introduction Bilirubin has been found to be a natural antioxidant protecting the body from oxidative stress. This study aims to investigate the severity of neonatal hypoxic injury on bilirubin levels to clarify the physiological role of bilirubin.

Study Design Using lactate as a biomarker for the severity of hypoxic injury, we retrospectively analyzed the association of admission lactate levels on serum total bilirubin (TB) levels following birth in neonates with hypoxic–ischemic encephalopathy (HIE). We created a univariate linear regression model to predict TB using the admission lactate level as a predictor. We also performed a multivariate linear regression analysis to predict TB with admission lactate levels that included phenobarbital cumulative dosage, admission hematocrit, and subgaleal hemorrhage as predictor variables.

Results A total of 86 patients were studied. Admission lactate levels had a significant negative effect on TB from admission to 3 days of life. The standardized regression coefficient for admission lactate on TB was −0.37 (admission), −0.42 (day 1), −0.32 (day 2), and −0.28 (day 3). A similar negative effect of admission lactate on TB levels was also observed in the multivariate linear regression model even after controlling for the other variables.

Conclusion These results are consistent with the hypothesis that bilirubin functions as an antioxidant in vivo, and is consumed by scavenging free radicals in proportion to the severity of hypoxic injury.

Key Points
The Austrian Corona Panel Project: monitoring individual and societal dynamics amidst the COVID-19 crisis
Authors: Kittel Bernhard , Kritzinger Sylvia , Boomgaarden Hajo , Prainsack Barbara , Eberl Jakob-Moritz , Kalleitner Fabian , Lebernegg Noëlle S. , Partheymüller Julia , Plescia Carolina , Schiestl David W. , Schlogl Lukas
Published: October 2020

Systematic and openly accessible data are vital to the scientific understanding of the social, political, and economic consequences of the COVID-19 pandemic. This article introduces the Austrian Corona Panel Project (ACPP), which has generated a unique, publicly available data set from late March 2020 onwards. ACPP has been designed to capture the social, political, and economic impact of the COVID-19 crisis on the Austrian population on a weekly basis. The thematic scope of the study covers several core dimensions related to the individual and societal impact of the COVID-19 crisis. The panel survey has a sample size of approximately 1500 respondents per wave. It contains questions that are asked every week, complemented by domain-specific modules to explore specific topics in more detail. The article presents details on the data collection process, data quality, the potential for analysis, and the modalities of data access pertaining to the first ten waves of the study.
Theory suggests Earth’s pivotal catastrophes can be understood through depth dimension
Authors: Gasparini Allison
Published: October 2020

A new hypothesis known as 4D Earth puts forth the idea that the depth dimension of our planet is the key factor behind past transformative events.
Coexisting hidden and self-excited attractors in a locally active memristor-based circuit
Authors: Dong Yujiao , Wang Guangyi , Iu Herbert Ho-Ching , Chen Guanrong , Chen Long
Published: October 2020

This paper presents a chaotic circuit based on a nonvolatile locally active memristor model, with non-volatility and local activity verified by the power-off plot and the DC V–I plot, respectively. It is shown that the memristor-based circuit has no equilibrium with appropriate parameter values and can exhibit three hidden coexisting heterogeneous attractors including point attractors, periodic attractors, and chaotic attractors. As is well known, for a hidden attractor, its attraction basin does not intersect with any small neighborhood of any unstable equilibrium. However, it is found that some attractors of this circuit can be excited from an unstable equilibrium in the locally active region of the memristor, meaning that its basin of attraction intersects with neighborhoods of an unstable equilibrium of the locally active memristor. Furthermore, with another set of parameter values, the circuit possesses three equilibria and can generate self-excited chaotic attractors. Theoretical and simulated analyses both demonstrate that the local activity and an unstable equilibrium of the memristor are two reasons for generating hidden attractors by the circuit. This chaotic circuit is implemented in a digital signal processing circuit experiment to verify the theoretical analysis and numerical simulations.
Direct electron acceleration in multi-kilojoule, multi-picosecond laser pulses
Authors: Kemp A. J. , Wilks S. C.
Published: October 2020

The physics mechanism behind the acceleration of electrons to energies much higher than the laser ponderomotive potential is reported. While electrons with these energies have been observed for the last twenty years at the one percent level, it is only with the recent advent of high power lasers with extended pulse durations, large focal spots, and high intensities that significant numbers (>10%) of the so-called “superponderomotive” electrons have been observed. Evidence is provided that the dominant acceleration mechanism of superponderomotive electrons is direct acceleration by the electromagnetic (EM) wave of the laser as they co-propagate in an under-dense plasma; one-dimensional particle-in-cell simulations yield electron spectra with typically ten times the ponderomotive temperature. Direct acceleration requires tens of plasma wavelengths of under-dense plasma, as well as pulse durations of tens of plasma periods, conditions that can be found in large focal spot multi-picosecond laser pulses. It is shown that the plasma simply provides the source of accelerated electrons and a variety of methods to inject a significant population of electrons into the EM waves at relativistic energy.
High-precision shock equation of state measurements for metallic fluid carbon between 15 and 20 Mbar
Authors: Millot Marius , Sterne Philip A. , Eggert Jon H. , Hamel Sebastien , Marshall Michelle C. , Celliers Peter M.
Published: October 2020

Diamond is an efficient ablator material to convert the energy of high-power giant lasers into ablation pressure with applications for High-Energy-Density (HED) science, planetary science, and Inertial Confinement Fusion (ICF) research at the National Ignition Facility (NIF). Unfortunately, current theoretical equation of state models cannot reproduce all the observed experimental data in the multi-megabar regime particularly relevant for HED and ICF research. New experimental data on the behavior of carbon at extreme pressures and temperatures are, therefore, essential to improve our predictive capability to design and analyze dynamic compression experiments for HED or ICF research and build improved equation of state models in the future. Here, we report high-precision laser-driven shock compression measurements on diamond single crystals at the Omega Laser Facility. Using ultrafast Doppler optical Velocimetry Interferometer System for Any Reflector (VISAR) to track the leading shock front and a quartz plate as an in situ reference, we obtain relative pressure-density shock equation-of-state measurements between 15 and 20 Mbar with an impedance-matching procedure. We also report shock-and-release measurements in a spherical geometry at the NIF. The new data provide tight constraints on the compressibility of warm dense carbon along the Hugoniot of full density diamond, allowing us to discriminate between existing theoretical equation-of-state models. We find that both LLNL LEOS 9061 and LANL Sesame 7835 models capture well the shock compressibility in the explored range. LANL Sesame 7835 also reproduces well the observed shock-and-release behavior of diamond near 10–20 Mbar.
A novel electrochemical anodization cell for the synthesis of mesoporous silicon
Authors: Gostkowska-Lekner N. , Wallacher D. , Grimm N. , Habicht K. , Hofmann T.
Published: October 2020

A novel design of an electrochemical anodization cell dedicated to the synthesis of mesoporous, single-crystalline silicon is presented. First and foremost, the design principle follows user safety since electrochemical etching of silicon requires highly hazardous electrolytes based on hydrofluoric (HF) acid. The novel cell design allows for safe electrolyte handling prior, during, and post-etching. A peristaltic pump with HF-resistant fluoroelastomer tubing transfers electrolytes between dedicated reservoirs and the anodization cell. Due to the flexibility of the cell operation, different processing conditions can be realized providing a large parameter range for the attainable sample thickness, its porosity, and the mean pore size. Rapid etching on the order of several minutes to synthesize micrometer-thick porous silicon epilayers on bulk silicon is possible as well as long-time etching with continuous, controlled electrolyte flow for several days to prepare up to 1000 μm thick self-supporting porous silicon membranes. A highly adaptable, LabVIEW™-based control software allows for user-defined etching profiles.
Quantum Gaudin model, spin chains, and universal characters
Authors: Li Chuanzhong , Shou Bao
Published: October 2020

In this paper, we will construct the connection between the quantum Gaudin model and the universal character hierarchy by a newly defined coupled master T-operator. The coupled master T-operator of the quantum Gaudin model satisfies the bilinear identity of the universal character hierarchy, which is an extension of the Kadomtsev–Petviashvili hierarchy. In addition, for the generalized quantum integrable spin chains with rational GL(N)-invariant R-matrices, we construct its coupled master T-operator, which represents a generating function for two-folds commuting quantum transfer matrices. The functional relations for the transfer matrices are equivalent to an infinite set of Hirota bilinear equations of the modified universal character hierarchy.
Identifying crystal structures and chemical reactions at the interface of stanene on Bi2Te3
Authors: Albright Stephen D , Zou Ke , Lau Claudia , Eltinge Stephen , Hong Hawoong , Ismail-Beigi Sohrab , Walker Frederick J. , Ahn Charles H.
Published: October 2020

Synthesizing monolayers and heterostructures is an enabling approach to extract new physical phenomena from bulk materials. Among the structures amenable to this approach is stanene, which is a monolayer of tin, similar to graphene, and has been predicted to host one-dimensional topological states at its edges. Stanene can be tuned by decorating with different adatoms, which makes it a promising platform on which to engineer topological devices. Here, we deposit Sn on Bi2Te3 and characterize the growth using anomalous synchrotron x-ray scattering and x-ray photoelectron spectroscopy (XPS). X-ray diffraction data reveal the formation of epitaxial Sn-based structures, along with penetration of Sn into the Bi2Te3, with Sn intercalating between the upper 10 Bi2Te3 quintuple layers. Additionally, XPS data show deposited Sn reacting to form SnTe and Bi at the Bi2Te3 surface. The calculated heat of reaction for Sn and Bi2Te3 is consistent with an exothermic reaction to SnTe and Bi. Using thermodynamic calculations as a guide, we identify several candidate substrates that can stabilize the stanene phase.
Electrostatic ion acceleration in an inductive radio-frequency plasma thruster
Authors: Sekine H. , Koizumi H. , Komurasaki K.
Published: October 2020

Spatially and temporally resolved ion flow measurements are performed inside the plasma source of an inductive radio frequency plasma thruster. Using the resulting data, the pure effects of the inductive current drive on the ion flow are identified. The cross field ion acceleration and the establishment of the cross field electric field are found in the upstream region, where the azimuthal current is induced by the superimposition of a time-varying magnetic field. Analyzing the electron and ion dynamics with two-fluid equations, the magnetized electrons form the in-plane Hall electric field to satisfy the electron force balance, which results in the electrostatic acceleration of unmagnetized ions. The enhanced density gradient forms a stronger Boltzmann electric field along the magnetic field. It generates a supersonic ion group along the magnetic field line, which increases the field-aligned ion flow velocity and the momentum thrust.
Digital quantum groups
Authors: Majid S. , Pachoł A.
Published: October 2020

We find and classify all bialgebras and Hopf algebras or “quantum groups” of dimension ≤4 over the field F2={0,1}. We summarize our results as a quiver, where the vertices are the inequivalent algebras and there is an arrow for each inequivalent bialgebra or Hopf algebra built from the algebra at the source of the arrow and the dual of the algebra at the target of the arrow. There are 314 distinct bialgebras and, among them, 25 Hopf algebras, with at most one of these from one vertex to another. We find a unique smallest noncommutative and noncocommutative one, which is moreover self-dual and resembles a digital version of uq(sl2). We also find a unique self-dual Hopf algebra in one anyonic variable x4 = 0. For all our Hopf algebras, we determine the integral and associated Fourier transform operator, viewed as a representation of the quiver. We also find all quasitriangular or “universal R-matrix” structures on our Hopf algebras. These induce solutions of the Yang–Baxter or braid relations in any representation.
Surface-enhanced fluorescence imaging on linear arrays of plasmonic half-shells
Authors: Farcau Cosmin , Craciun Ana-Maria , Vallée Renaud A. L.
Published: October 2020

Here, we perform a Surface-Enhanced Fluorescence (SEF) intensity and lifetime imaging study on linear arrays of silver half-shells (LASHSs), a class of polarization-sensitive hybrid colloidal photonic–plasmonic crystal unexplored previously in SEF. By combining fluorescence lifetime imaging microscopy, scanning confocal fluorescence imaging, Rayleigh scattering imaging, optical microscopy, and finite difference time domain simulations, we identify with high accuracy the spatial locations where SEF effects (intensity increase and lifetime decrease) take place. These locations are the junctions/crevices between adjacent half-shells in the LASHS and locations of high electromagnetic field enhancement and strong emitter–plasmon interactions, as confirmed also by simulated field maps. Such detailed knowledge of the distributed SEF enhancements and lifetime modification distribution, with respect to topography, should prove useful for improved future evaluations of SEF enhancement factors and a more rational design of efficiency-optimized SEF substrates. These linear arrays of metal-coated microspheres expand the family of hybrid colloidal photonic–plasmonic crystals, platforms with potential for applications in optoelectronic devices, fluorescence-based (bio)chemical sensing, or medical assays. In particular, due to the polarized optical response of these LASHSs, specific applications such as hidden tags for anti-counterfeiting or plasmon-enhanced photodetection can be foreseen.
Temperature-transferable coarse-graining of ionic liquids with dual graph convolutional neural networks
Authors: Ruza Jurgis , Wang Wujie , Schwalbe-Koda Daniel , Axelrod Simon , Harris William H. , Gómez-Bombarelli Rafael
Published: October 2020

Computer simulations can provide mechanistic insight into ionic liquids (ILs) and predict the properties of experimentally unrealized ion combinations. However, ILs suffer from a particularly large disparity in the time scales of atomistic and ensemble motion. Coarse-grained models are therefore used in place of costly all-atom simulations, accessing longer time scales and larger systems. Nevertheless, constructing the many-body potential of mean force that defines the structure and dynamics of a coarse-grained system can be complicated and computationally intensive. Machine learning shows great promise for the linked challenges of dimensionality reduction and learning the potential of mean force. To improve the coarse-graining of ILs, we present a neural network model trained on all-atom classical molecular dynamics simulations. The potential of mean force is expressed as two jointly trained neural network interatomic potentials that learn the coupled short-range and many-body long range molecular interactions. These interatomic potentials treat temperature as an explicit input variable to capture its influence on the potential of mean force. The model reproduces structural quantities with high fidelity, outperforms the temperature-independent baseline at capturing dynamics, generalizes to unseen temperatures, and incurs low simulation cost.
The nature of the chemical bond in the dicarbon molecule
Authors: Genovese Claudio , Sorella Sandro
Published: October 2020

The molecular dissociation energy has often been explained and discussed in terms of singlet bonds, formed by bounded pairs of valence electrons. In this work, we use a highly correlated resonating valence bond ansatz, providing a consistent paradigm for the chemical bond, where spin fluctuations are shown to play a crucial role. Spin fluctuations are known to be important in magnetic systems and correspond to the zero point motion of the spin waves emerging from a magnetic broken symmetry state. Within our ansatz, a satisfactory description of the carbon dimer is determined by the magnetic interaction of two carbon atoms with antiferromagnetically ordered S = 1 magnetic moments. This is a first step that, thanks to the highly scalable and efficient quantum Monte Carlo techniques, may open the door for understanding challenging complex systems containing atoms with large spins (e.g., transition metals).
Mesoscopic simulation of three-dimensional pool boiling based on a phase-change cascaded lattice Boltzmann method
Authors: Fei Linlin , Yang Jiapei , Chen Yiran , Mo Huangrui , Luo Kai H.
Published: October 2020

In this paper, a three-dimensional (3D) cascaded lattice Boltzmann method (CLBM) is implemented to simulate the liquid–vapor phase-change process. The multiphase flow field is solved by incorporating the pseudopotential multiphase model into an improved CLBM, the temperature field is solved by the finite difference method, and the two fields are coupled via a non-ideal equation of state. Through numerical simulations of several canonical problems, it is verified that the proposed phase-change CLBM is applicable for both the isothermal multiphase flow and the liquid–vapor phase-change process. Using the developed method, a complete 3D pool boiling process with up to hundreds of spontaneously generated bubbles is simulated, faithfully reproducing the nucleate boiling, transition boiling, and film boiling regimes. It is shown that the critical heat flux predicted by the 3D simulations agrees better with the established theories and correlation equations than that obtained by two-dimensional simulations. Furthermore, it is found that with the increase in the wall superheats, the bubble footprint area distribution changes from an exponential distribution to a power-law distribution, in agreement with experimental observations. In addition, insights into the instantaneous and time-averaged characteristics of the first two largest bubble footprints are obtained.
The temperature rise characteristics analysis and experiment of GMA
Authors: Xie Tian , Wang Chuanli , Yu Caofeng , Xu Bin , Shi Rui
Published: October 2020

The giant magnetostrictive actuator (GMA) with giant magnetostrictive material (GMM) as the core component has wide applications in the field of precision drive and control. In this paper, through the analysis of the GMA coil, the loss and temperature rise characteristics of the GMA have been studied. Then, COMSOL Multiphysics software has been used to model the heat source distribution of the GMM actuator, and the factors affecting the working temperature of the GMM rod have been analyzed. Finally, based on the use requirements of the GMA, magnetic field, and internal temperature distribution characteristics, the heat dissipation scheme of the coil is proposed, and the experimental platform of the GMA with a thermal compensation function is built to verify the temperature characteristics and thermal compensation effect. Studying the internal temperature distribution law of the GMA not only has a guiding significance for the temperature control of the actuator and the design of the cooling system but also reduces the influence of the coil thermal effect on the performance of the transducer and lays the foundation for making full use of the GMM’s potential in high-power transducers.
Vibronic coupling in the ground and excited states of the pyridine radical cation
Authors: Trofimov A. B. , Skitnevskaya A. D. , Grigoricheva E. K. , Gromov E. V. , Köppel H.
Published: October 2020

Vibronic interactions in the pyridine radical cation ground state, 2A1, and its lowest excited states, 2A2 and 2B1, are studied theoretically. These states originate from the ionization out of the highest occupied orbitals of pyridine, 7a1 (nσ), 1a2 (π), and 2b1 (π), respectively, and give rise to the lowest two photoelectron maxima. According to our previous high-level ab initio calculations [Trofimov et al., J. Chem. Phys. 146, 244307 (2017)], the 2A2 (π−1) excited state is very close in energy to the 2A1 (nσ−1) ground state, which suggests that these states could be vibronically coupled. Our present calculations confirm that this is indeed the case. Moreover, the next higher excited state, 2B1 (π−1), is also involved in the vibronic interaction with the 2A1 (nσ−1) and 2A2 (π−1) states. The three-state vibronic coupling problem was treated within the framework of a linear vibronic coupling model employing parameters derived from the ionization energies of pyridine computed using the linear response coupled-cluster method accounting for single, double, and triple excitations (CC3). The potential energy surfaces of the 2A1 and 2A2 states intersect in the vicinity of the adiabatic minimum of the 2A2 state, while the surfaces of the 2A2 and 2B1 states intersect near the 2B1 state minimum. The spectrum computed using the multi-configuration time-dependent Hartree (MCTDH) method accounting for 24 normal modes is in good qualitative agreement with the experimental spectrum of pyridine obtained using high-resolution He I photoelectron spectroscopy and allows for some assignment of the observed features.
Vibrationally inelastic scattering of HCl from Ag(111)
Authors: Geweke Jan , Wodtke Alec M.
Published: October 2020

Using molecular beam cooled samples and quantum state-selective detection, we observe v = 0 → 1 vibrational transitions when HCl (v = 0) collides with an Ag(111) surface and derive both the incidence energy and surface temperature dependence of the transition probability. Our observations reveal that both electronically adiabatic and non-adiabatic mechanisms are at play in this inelastic process. A comparison to other systems shows similarities and trends that are consistent with an electron transfer mechanism forming a transient HCl−. For example, the electronically nonadiabatic coupling is stronger than for HCl scattering from Au, where the solid’s work function is higher. HCl differs from other systems in that dissociation is possible over a low barrier. Vibrationally inelastic v = 1 → 2 transitions could not be seen when HCl (v = 1) collides with an Ag(111) surface. We suggest that scattering events, where HCl (v = 1) is subject to dynamical influences that increase its vibrational energy, lead efficiently to dissociation before the HCl (v = 2) molecule can escape the surface. This system appears to be an excellent candidate to study electronically nonadiabatic effects in dissociative adsorption.
Circular dichroism of doped carbon nanotubes
Authors: Saito Riichiro , Ukhtary M. Shoufie , Wang Sake , Iwasaki Yuya
Published: October 2020

Circular dichroism (CD) of a doped carbon nanotube is calculated as a function of wavelength for several values of the Fermi energy. In the calculation of CD, we consider the so-called depolarization effect by taking account of the dielectric function that suppresses or enhances the electric field inside the undoped or doped nanotube, respectively. Because of the induced electric current of the carriers, the CD of a doped carbon nanotube becomes much larger than that of an undoped nanotube when we select the light-propagating direction parallel to the nanotube axis. The sign of CD changes for enantiomer pair of nanotubes or for type-I and type-II semiconductor nanotubes or by changing the Fermi energy, which is useful for identifying nanotubes in the device.
Isotope enrichment in neon clusters grown in helium nanodroplets
Authors: Tiefenthaler Lukas , Kollotzek Siegfried , Gatchell Michael , Hansen Klavs , Scheier Paul , Echt Olof
Published: October 2020

Neon cluster ions Nes+ grown in pre-ionized, mass-to-charge selected helium nanodroplets (HNDs) reveal a strong enrichment of the heavy isotope 22Ne that depends on cluster size s and the experimental conditions. For small sizes, the enrichment is much larger than previously reported for bare neon clusters grown in nozzle expansions and subsequently ionized. The enrichment is traced to the massive evaporation of neon atoms in a collision cell that is used to strip helium from the HNDs. We derive a relation between the enrichment of 22Ne in the cluster ion and its corresponding depletion factor F in the vapor phase. The value thus found for F is in excellent agreement with a theoretical expression that relates isotopic fractionation in two-phase equilibria of atomic gases to the Debye temperature. Furthermore, the difference in zero-point energies between the two isotopes computed from F agrees reasonably well with theoretical studies of neon cluster ions that include nuclear quantum effects in the harmonic approximation. Another fitting parameter provides an estimate for the size si of the precursor of the observed Nes+. The value is in satisfactory agreement with the size estimated by modeling the growth of Nes+ and with lower and upper limits deduced from other experimental data. On the other hand, neon clusters grown in neutral HNDs that are subsequently ionized by electron bombardment exhibit no statistically significant isotope enrichment at all. The finding suggests that the extent of ionization-induced dissociation of clusters embedded in HNDs is considerably smaller than that for bare clusters.
Ag5-induced stabilization of multiple surface polarons on perfect and reduced TiO2 rutile (110)
Authors: López-Caballero P. , Miret-Artés S. , Mitrushchenkov A. O. , de Lara-Castells M. P.
Published: October 2020

The recent advent of cutting-edge experimental techniques allows for a precise synthesis of subnanometer metal clusters composed of just a few atoms, opening new possibilities for subnanometer science. In this work, via first-principles modeling, we show how the decoration of perfect and reduced TiO2 surfaces with Ag5 atomic clusters enables the stabilization of multiple surface polarons. Moreover, we predict that Ag5 clusters are capable of promoting defect-induced polarons transfer from the subsurface to the surface sites of reduced TiO2 samples. For both planar and pyramidal Ag5 clusters, and considering four different positions of bridging oxygen vacancies, we model up to 14 polaronic structures, leading to 134 polaronic states. About 71% of these configurations encompass coexisting surface polarons. The most stable states are associated with large inter-polaron distances (>7.5 Å on average), not only due to the repulsive interaction between trapped Ti3+ 3d1 electrons, but also due to the interference between their corresponding electronic polarization clouds [P. López-Caballero et al., J. Mater. Chem. A 8, 6842–6853 (2020)]. As a result, the most stable ferromagnetic and anti-ferromagnetic arrangements are energetically quasi-degenerate. However, as the average inter-polarons distance decreases, most (≥70%) of the polaronic configurations become ferromagnetic. The optical excitation of the midgap polaronic states with photon energy at the end of the visible region causes the enlargement of the polaronic wave function over the surface layer. The ability of Ag5 atomic clusters to stabilize multiple surface polarons and extend the optical response of TiO2 surfaces toward the visible region bears importance in improving their (photo-)catalytic properties and illustrates the potential of this new generation of subnanometer-sized materials.
Prediction of dressing percentage, carcass characteristics and meat yield of goats, and implications for live assessment and carcass-grading systems
Authors: Greenwood Paul L.
Published: October 2020

Abstract

Context
Dressing percentage (DP) and meat yield (MY) predictions using live assessments and carcass measurements enable objective valuation of animals and their carcasses. We hypothesised that distribution of goat carcass tissues affects predictive value of live body condition scoring (CS) methods and carcass measurements for these traits.

Aims
The present paper aimed to assess the value of CS methods for prediction of DP and MY and of carcass measurements for prediction of MY.

Methods
Correlation and regression analyses from a dataset (n = 1014 goats) highly heterogeneous for factors influencing DP and MY were used to assess (1) the value of live-goat assessments and classifications, including five CS methods, age (dentition), liveweight (LW), sex, fleece characteristics and breed or genotype to predict DP and MY, and (2) the value of hot standard carcass weight (HSCW) and carcass GR (soft tissue over the 12th rib) tissue depth, eye-muscle depth and eye-muscle area to predict MY.

Key results
Among kids, LW accounted for 1% (residual standard deviation of 2.6%) of variation in DP, 22% (2.3%) in MY (% LW) and 34% (2.5%) in MY (% HSCW). LW plus the best CS method accounted for 24% (2.3%) of variation in DP, 58% (1.7%) in MY (% LW) and 61% (2.0%) in MY (% HSCW). Among all goats, LW plus CS accounted for up to 21% (3.2%), 39% (2.1%) and 45% (2.2%) of variation in these traits. Regression models that included age, sex, fleece type, breed or genotype, LW and CS accounted for 67% (2.5%), 72% (1.9%) and 72% (2.1%) of variation in DP, MY (% LW) and MY (% HSCW). Among carcass measurements, HSCW plus eye-muscle depth had best predictive value, accounting for 61% (2.3%) of variation in MY (% HSCW) for kids and 40% (2.9%) for all goats.

Conclusions
The body condition-score methods that best relate to DP and MY (% LW or % HSCW) assessed the shape of M. longissimus lumborum (eye muscle) in the lumbar region, which relates to muscularity of goats, rather than subcutaneous fat depth such as assessed at the GR-site.

Implications
The results guide potential targets for future developments in live-goat assessment, carcass classification and grading, and trading languages underpinned by value-based marketing.