bluuebunny/crossref_metadata_2025 huggingface dataset:
Relevante Aspekte der arzneimittelassoziierten Hepatotoxizität im klinischen Alltag
Authors: Zeiss René , Gahr Maximilian
Published: February 2021

Gegenstand und Ziel Arzneimittelassoziierte Hepatotoxizität (engl. Drug-induced liver injury, DILI) ist einer der häufigsten Gründe für akutes Leberversagen und die Rücknahme der Zulassung von Arzneimitteln. Das Risiko des Auftretens von DILI im Zusammenhang mit der Anwendung spezifischer Substanzen ist grundsätzlich gering, allerdings kann DILI letal verlaufen und stellt daher ein ernstzunehmendes Problem im klinischen Alltag dar. In der vorliegenden Übersichtsarbeit wird ein Überblick über den Kenntnisstand zu DILI mit Fokus auf klinisch relevante Aspekte gegeben.

Material und Methoden Es wurde eine narrative Übersichtsarbeit erstellt. Die Literaturrecherche wurde mithilfe der bibliografischen Datenbank MEDLINE durchgeführt.

Ergebnisse DILI ist eine unerwünschte Arzneimittelwirkung, welche sowohl in direkter, vorhersehbarer als auch idiosynkratrischer, unvorhersehbarer Form auftreten kann. Die Ätiologie von DILI wird als multifaktoriell bewertet und es scheinen genetische, immunologische und Umweltfaktoren eine Rolle zu spielen. Therapeutisch stellen das Absetzen der verdächtigten Substanz sowie eine engmaschige Überwachung des Patienten die wichtigsten Maßnahmen dar.

Schlussfolgerungen und klinische Relevanz Die große Anzahl an Substanzen mit hepatotoxischem Potenzial sowie die begrenzte Vorhersagbarkeit von DILI in Kombination mit den begrenzten therapeutischen Möglichkeiten stellen eine Herausforderung im klinischen Alltag dar. Bei Auftreten von Transaminasenerhöhungen unklarer Genese sollte DILI in Betracht gezogen und es sollten entsprechende Maßnahmen ergriffen werden.
High-Impact Details of Play and Movements in Female Basketball Game
Authors: Nagano Yasuharu , Sasaki Shogo , Shimada Yui , Koyama Takeshi , Ichikawa Hiroshi
Published: February 2021

This study aimed to identify the high-impact details of play and movements with higher acceleration and their frequency during a female basketball match. Trunk acceleration was measured during a simulated basketball game with eight female players. The extracted instance was categorized, which generated at > 6 and 8 G resultant accelerations using a video recording and an accelerometer attached to the players’ trunk, as details of play and movements. The frequency and ratio of the details of play and movements regarding all detected movements were calculated. A total of 1062 and 223 play actions were detected for the resultant acceleration thresholds of > 6 and 8 G, respectively. For these acceleration thresholds, in terms of details of play, positioning on the half-court was the most frequently observed (29.6 and 23.8%, respectively). In terms of movements, deceleration was the most frequently detected movement (21.5 and 23.3%, respectively), followed by landing (7.6 and 15.7%, respectively). Deceleration during positioning on the half-court and defense as well as landing mostly after a shot were detected as high-impact frequent basketball-specific movements. The results also showed that characteristics of movements or playing style and playing position may have an effect on acceleration patterns during a basketball game.
Predictive factors for adenoma detection rates: a video study of endoscopist practices
Authors: Yang Sun Young , Quan Susan Y. , Friedland Shai , Pan Jennifer Y.
Published: February 2021

Background and study aims In 2015, the American Society for Gastrointestinal Endoscopy (ASGE) and American College of Gastroenterology (ACG) Task Force on Quality in Endoscopy deemed adenoma detection rate (ADR) the most important quality measure for colonoscopy. There has been much interest in factors that can increase ADR. To date, however, few studies have looked at what intra-procedural endoscopist practices are associated with improving ADR. We conducted a retrospective review of colonoscopy videos to evaluate intra-procedural practices that could be associated with ADR.

Methods Videos were recorded of colonoscopies performed between September and December 2017 at the Palo Alto Veterans Affairs Health Care System. Colonoscopies for screening and surveillance were included for video review. Factors assessed included withdrawal time, intra-procedural cleaning, inspection technique, and other variables (colon distention, removal of equivocal/hyperplastic polyps). A series of multiple regression analyses was conducted on variables of interest before running a final model of significant predictors.

Results A total of 130 videos were reviewed from nine endoscopists whose ADRs ranged between 37.5 % and 73.7 %. The final regression model was significant (F = 15.35, df = 2, P = 0.0044), R2 = 0.8365) with close inspection of behind folds and quality of cecal inspection being the factors highly correlated with predicting ADR. Withdrawal and inspection times, colonic wall distention, removal of equivocal/hyperplastic polyps, quality of rectal inspection, suctioning, and washing were factors moderately correlated with predicting ADR.

Conclusions We found that behind-fold inspection and a meticulous cecal inspection technique were predictive of a high ADR.
Improvement in adenoma detection using a novel artificial intelligence-aided polyp detection device
Authors: Shaukat Aasma , Colucci Daniel , Erisson Lavi , Phillips Sloane , Ng Jonathan , Iglesias Juan Eugenio , Saltzman John R. , Somers Samuel , Brugge William
Published: February 2021

Background and study aims Detecting colorectal neoplasia is the goal of high-quality screening and surveillance colonoscopy, as reflected by high adenoma detection rate (ADR) and adenomas per colonoscopy (APC). The aim of our study was to evaluate the performance of a novel artificial intelligence (AI)-aided polyp detection device, Skout, with the primary endpoints of ADR and APC in routine colonoscopy.

Patients and methods We compared ADR and APC in a cohort of outpatients undergoing routine high-resolution colonoscopy with and without the use of a real-time, AI-aided polyp detection device. Patients undergoing colonoscopy with Skout were enrolled in a single-arm, unblinded, prospective trial and the results were compared with a historical cohort. All resected polyps were examined histologically.

Results Eighty-three patients undergoing screening and surveillance colonoscopy at an outpatient endoscopy center were enrolled and outcomes compared with 283 historical control patients. Overall, ADR with and without Skout was 54.2 % and 40.6 % respectively (P = 0.028) and 53.6 % and 30.8 %, respectively, in screening exams (P = 0.024). Overall, APC rate with and without Skout was 1.46 and 1.01, respectively, (P = 0.104) and 1.18 and 0.50, respectively, in screening exams (P = 0.002). Overall, true histology rate (THR) with and without Skout was 73.8 % and 78.4 %, respectively, (P = 0.463) and 75.0 % and 71.0 %, respectively, in screening exams (P = 0.731).

Conclusion We have demonstrated that our novel AI-aided polyp detection device increased the ADR in a cohort of patients undergoing screening and surveillance colonoscopy without a significant concomitant increase in hyperplastic polyp resection. AI-aided colonoscopy has the potential for improving the outcomes of patients undergoing colonoscopy.
Long-term outcomes of transoral incisionless fundoplication for gastro-esophageal reflux disease: systematic-review and meta-analysis
Authors: Testoni Sabrina , Hassan Cesare , Mazzoleni Giorgia , Antonelli Giulio , Fanti Lorella , Passaretti Sandro , Correale Loredana , Cavestro Giulia Martina , Testoni Pier Alberto
Published: February 2021

Background and study aims Few reports exist about long-term outcomes of transoral incisionless fundoplication (TIF) for treating refractory gastro-esophageal reflux disease (GERD).

Methods A literature search of four major scientific databases was performed up to May 2020 for studies reporting on more than 3-year outcomes of TIF. Data on atient satisfaction, proton pump inhibitor (PPI) daily consumption, PPI use reduction, GERD health-related quality-of-life (GERD-HRQL) score, and normalization of heartburn and regurgitation scores were pooled and summarized with forest plots. Publication bias and heterogeneity were explored.

Results Overall, eight studies (418 patients, 232 men; 55.5 %) with a mean follow-up of 5.3 years (range: 3–10 years) were included. The pooled proportion of patient-reported satisfaction before and after TIF was 12.3 % (95 % CI:12.3–35.1 %, I2 = 87.4 %) and 70.6 % (95 % CI:51.2–84.6, I2 = 80 %), respectively, corresponding to an odds ratio of 21.4 (95 % CI:3.27–140.5). Pooled rates of patients completely off PPIs and on occasional PPIs were 53.8 % (95 %CI: 42.0 %-65.1 %) and 75.8 % (95 %CI: 67.6–82.6), respectively. The pooled estimated mean GERD-HRQL scores off PPI before and after TIF werey 26.1 (95 %CI: 21.5–30.7; range: 20.0–35.5) and 5.9, respectively (95 %CI:0.35.1–11.4; range: 5.3–9.8; P < 0.001). The overall pooled rates of heartburn and regurgitation scores normalization were 73.0 % (95 %CI: 0.62–0.82) and 86 %, respectively (95 %CI: 75.0–91.0 %).

Conclusion Our study shows that TIF appears to offer a long-term safe therapeutic option for selected patients with GERD who refuse life-long medical therapy or surgery, are intolerant to PPIs, or are at increased surgical risk.
Adverse events of colonoscopy in a colorectal cancer screening program with fecal immunochemical testing: a population-based observational study
Authors: Denis Bernard , Gendre Isabelle , Weber Sarah , Perrin Philippe
Published: February 2021

Background and study aims The aim of this study was to assess adverse events (AEs) associated with colonoscopy in the French colorectal cancer screening program with fecal occult blood test (FOBT).

Patients and methods A retrospective cohort study was performed of all colonoscopies performed from 2015 to 2018 for a positive fecal immunochemical test (FIT) in patients aged 50 to 74 years within the screening program in progress in Alsace, part of the French program. AEs were recorded through prospective voluntary reporting by community gastroenterologists and retrospective postal surveys addressed to individuals screened. They were compared with those recorded in the previous program following colonoscopies performed from 2003 to 2014 for a positive guaiac-based FOBT (gFOBT).

Results Of 9576 colonoscopies performed for a positive FIT, 6194 (64.7 %) were therapeutic. Overall, 180 AEs were recorded (18.8 ‰, 95 % CI 16.1–21.5), 114 of them (11.9 ‰, 95 % CI 9.7–14.1) requiring hospitalization, 55 (5.7‰, 95 % CI 4.2–7.3) hospitalization > 24 hours, and eight (0.8 ‰, 95 % CI 0.3–1.4) surgery. The main complications requiring hospitalization were perforation (n = 18, 1.9 ‰, 95 % CI 1.0–2.7) and bleeding (n = 31, 3.2 ‰, 95 % CI 2.1–4.4). Despite a significant increase in several risk factors for complication, the rate of AEs remained stable between gFOBT and FIT programs. Overall, we observed one death (1/27,000 colonoscopies) and three splenic injuries.

Conclusions The harms of colonoscopy in a colorectal cancer screening program with FIT are more frequent than usually estimated. This study revealed six AEs requiring hospitalization > 24 hours (three bleeds, two perforations), one necessitating surgery, and 50 minor complications per 1000 colonoscopies.
Fast 3D Isotropic Proton Density-Weighted Fat-Saturated MRI of the Knee at 1.5 T with Compressed Sensing: Comparison with Conventional Multiplanar 2D Sequences
Authors: Endler Christoph H.-J. , Faron Anton , Isaak Alexander , Katemann Christoph , Mesropyan Narine , Kupczyk Patrick A. , Pieper Claus C. , Kuetting Daniel , Hadizadeh Dariusch R. , Attenberger Ulrike I. , Luetkens Julian A.
Published: February 2021

Purpose Compressed sensing (CS) is a method to accelerate MRI acquisition by acquiring less data through undersampling of k-space. In this prospective study we aimed to evaluate whether a three-dimensional (3D) isotropic proton density-weighted fat saturated sequence (PDwFS) with CS can replace conventional multidirectional two-dimensional (2D) sequences at 1.5 Tesla.

Materials and Methods 20 patients (45.2 ± 20.2 years; 10 women) with suspected internal knee damage received a 3D PDwFS with CS acceleration factor 8 (acquisition time: 4:11 min) in addition to standard three-plane 2D PDwFS sequences (acquisition time: 4:05 min + 3:03 min + 4:46 min = 11:54 min) at 1.5 Tesla. Scores for homogeneity of fat saturation, image sharpness, and artifacts were rated by two board-certified radiologists on the basis of 5-point Likert scales. Based on these ratings, an overall image quality score was generated. Additionally, quantitative contrast ratios for the menisci (MEN), the anterior (ACL) and the posterior cruciate ligament (PCL) in comparison with the popliteus muscle were calculated.

Results The overall image quality was rated superior in 3D PDwFS compared to 2D PDwFS sequences (14.45 ± 0.83 vs. 12.85 ± 0.99; p < 0.01), particularly due to fewer artifacts (4.65 ± 0.67 vs. 3.65 ± 0.49; p < 0.01) and a more homogeneous fat saturation (4.95 ± 0.22 vs. 4.55 ± 0.51; p < 0.01). Scores for image sharpness were comparable (4.80 ± 0.41 vs. 4.65 ± 0.49; p = 0.30). Quantitative contrast ratios for all measured structures were superior in 3D PDwFS (MEN: p < 0.05; ACL: p = 0.06; PCL: p = 0.33). In one case a meniscal tear was only diagnosed using multiplanar reformation of 3D PDwFS, but it would have been missed on standard multiplanar 2D sequences.

Conclusion An isotropic fat-saturated 3D PD sequence with CS enables fast and high-quality 3D imaging of the knee joint at 1.5 T and may replace conventional multiplanar 2D sequences. Besides faster image acquisition, the 3D sequence provides advantages in small structure imaging by multiplanar reformation.

Key Points: 

Citation Format
In-vitro Anti-trypanosomal and Cytotoxicity Evaluation of
3-methyl-3,4-dihydroquinazolin-2(1H)-one Derivatives
Authors: Jesumoroti Omobolanle J. , Beteck Richard M. , Legoabe Lesetja J.
Published: February 2021

Sleeping sickness, caused by trypanosomes, is a debilitating,
neglected tropical disease wherein current treatments suffer
from several drawbacks such as toxicity, low activity, and
poor pharmacokinetic properties, and hence the need for
alternative treatment is apparent. To this effect, we
screened in vitro a library of 2-quinazolinone derivatives
for antitrypanosomal activity against T.b. brucei and
cytotoxicity against HeLa cells. Seven compounds having no
overt cytotoxicity against HeLa cells exhibited
antitrypanosomal activity in the range of 0.093–45 µM were
identified. The activity data suggests that the
antitrypanosomal activity of this compound class is amenable
to substituents at N1 and C6 positions. Compound 14
having a molecular weight of 238Da, ClogP value of 1 and a
total polar surface area of 49 was identified as the most
active, exhibiting an IC50 value of 0.093 µM
Graphical
Abstract.
Effects of Different Amine Activators on the Monomer Conversion, Biaxial Flexural Strength, and Color Stability of Experimental Provisional Dental Restorations
Authors: Padunglappisit Chawal , Posaya-anuwat Siwanath , Sompoch Varisara , Piyawiwattanakoon Poompat , Panpisut Piyaphong
Published: February 2021

Objective The aim was to assess the effect of different amine activators including N, N-dimethyl-p-toluidine (DMPT) or Na-N-tolyglycine glycidyl methacrylate (NTGGMA) on chemical-activated monomer conversion, biaxial flexural strength (BFS), and color stability of composites for provisional dental restorations.

Materials and Methods Two formulations of composites containing either DMPT (D-temp) or NTGGMA (N-temp) were prepared. The degree of monomer conversion was assessed. The BFS of the materials was tested using the ball-on-ring testing jig. The color difference (∆E00) of the materials after immersion in water was also determined. The commercial comparisons were Unifast (UF), Protemp (PT), Luxacrown, and Luxatemp (LT).

Results The monomer conversion of D-temp (57.4 ± 1.3%) was comparable to that of N-temp (59.0 ± 1.3%). The conversion of both D-temp and N-temp were higher than that of PT (48.1 ± 3.4%) and LT (48.0 ± 1.6%). BFS of both D-temp (164.2 ± 18.1 MPa) and N-temp (168.6 ± 8.9 MPa) were comparable but higher than that of UF (119.8 ± 13.6 MPa). ∆E00 of D-temp (2.7 ± 0.7) and N-temp (2.5 ± 0.8) were comparable but higher than that of other commercial materials (0.6–1.2).

Conclusion The use of DMPT or NTGGMA showed negligible effect on monomer conversion, BFS, and color stability of the experimental provisional restorations. The conversion and BFS of the experimental materials were in the range of that obtained from commercial bis-acryl-based materials. However, the color stability of the experimental materials was lower than that of commercial materials.
Central Line Utilization and Complications in Infants with Congenital Diaphragmatic Hernia
Authors: Grover Theresa R. , Weems Mark F. , Brozanski Beverly , Daniel John , Haberman Beth , Rintoul Natalie , Walden Alyssa , Hedrick Holly , Mahmood Burhan , Seabrook Ruth , Murthy Karna , Zaniletti Isabella , Keene Sarah ,   on behalf of the Children's Hospitals Neonatal Consortium (CHNC) Congenital Diaphragmatic Hernia Focus Group
Published: February 2021

Objective Infants with congenital diaphragmatic hernia (CDH) require multiple invasive interventions carrying inherent risks, including central venous and arterial line placement. We hypothesized that specific clinical or catheter characteristics are associated with higher risk of nonelective removal (NER) due to complications and may be amenable to efforts to reduce patient harm.

Study Design Infants with CDH were identified in the Children's Hospital's Neonatal Database (CHND) from 2010 to 2016. Central line use, duration, and complications resulting in NER are described and analyzed by extracorporeal membrane oxygenation (ECMO) use.

Results A total of 1,106 CDH infants were included; nearly all (98%) had a central line placed, (average of three central lines) with a total dwell time of 22 days (interquartile range [IQR]: 14–39). Umbilical arterial and venous lines were most common, followed by extremity peripherally inserted central catheters (PICCs); 12% (361/3,027 central lines) were removed secondary to complications. Malposition was the most frequent indication for NER and was twice as likely in infants with intrathoracic liver position. One quarter of central lines in those receiving ECMO was placed while receiving this therapy.

Conclusion Central lines are an important component of intensive care for infants with CDH. Careful selection of line type and location and understanding of common complications may attenuate the need for early removal and reduce risk of infection, obstruction, and malposition in this high-risk group of patients.

Key Points
A tale of two pandemics: evolutionary psychology, urbanism, and the biology of disease spread deepen sociopolitical divides in the U.S.
Authors: Kuznar Lawrence A.
Published: February 2021

The COVID-19 pandemic has spread uncertainty and social disruption, and exacerbated political divides in the United States. Most studies of the drivers of the epidemic focus on victim characteristics without consideration of drivers in the general population. This study presents statistical models that track the underlying factors in the general population associated with the spread of the pandemic and addresses how social learning mechanisms have led people to adopt perspectives and behaviors depending on their social context. Despite many social, physiological and economic factors, the statistical drivers of the pandemic primarily relate to the presence of vectors and the probability of transmission. However, the relationship between these drivers and COVID-19 deaths is weak and variable outside of the New York metropolitan area. Furthermore, the per capita death rate in much of the country has been much lower than the New York metropolitan area. There have been two very different experiences with the pandemic, one where the signals of its danger have been obvious from the start and one where the signals have been much weaker. Social learning mechanisms (in-group information sharing, imitation, costly punishment) have amplified the effect of people’s experiences with the pandemic. Sheltering in cities and protesting shutdowns in rural areas probably were initially adaptive somatic efforts in the evolutionary sense, given the different realities of the pandemic versus its economic costs in urban versus rural environments. These adaptations, however, have deepened the political divides in an already Balkanized country. The paper concludes with practical recommendations for how to use social learning theory for disseminating information on how to combat the pandemic.
What happens to DNA under high shear rates?
Authors: Bandari Anashe
Published: February 2021

High shear rate studies are difficult to access due to equipment limitations. Understanding DNA behavior in this regime has important applications.
Optimizing hybrid energy storage systems for wind farms
Authors: Patrick Chris
Published: February 2021

A proposed model for a hybrid energy storage system could improve output fluctuation and electricity quality of large-scale on-grid wind farms.
Proposed scheme produces ultrabright attosecond gamma-ray bursts
Authors: Patrick Chris
Published: February 2021

Simulations show laser-plasma interactions generate gamma rays of attosecond duration with enough photon energy for applications in astrophysics, nuclear physics, materials science, and beyond.
Impact of high-dose gamma-ray irradiation on electrical characteristics of N-polar and Ga-polar GaN p–n diodes
Authors: Mirkhosravi F. , Rashidi A. , Gallagher J. , Monavarian M. , Aragon A. , Ahn K. , Ooi Y. K. , Lintereur A. , Mace E. K. , Scarpulla M. A. , Feezell D.
Published: February 2021

We investigate the impact of high-dose gamma-ray irradiation on the electrical performance of Ga-polar and N-polar GaN-based p–n diodes grown by metalorganic chemical vapor deposition. We compare the current density–voltage (J–V), capacitance–voltage (C–V), and circular transfer length method characteristics of the p–n diodes fabricated on Ga-polar and N-polar orientations before and after irradiation. The relative turn-on voltage increases for the Ga-polar diodes with an increasing irradiation dose, while it increases initially and then starts to decrease for the N-polar diodes. The p-contact total resistance increases for Ga-polar and decreases for N-polar samples, which we attribute to the formation of point defects and additional Mg activation after irradiation. The J–V characteristics of most of the tested diodes recovered over time, suggesting the changes in the J–V characteristics are temporary and potentially due to metastable occupancy of traps after irradiation. X-ray photoelectron spectroscopy and photoluminescence measurements reveal the existence of different types of initial defects and surface electronic states on Ga-polar and N-polar samples. Gallium vacancies (VGa) are dominant defects in Ga-polar samples, while nitrogen vacancies (VN) are dominant in N-polar samples. The presence of a higher concentration of surface states on Ga-polar surfaces than N-polar surfaces was confirmed by calculating the band bending and the corresponding screening effect due to opposite polarization bound charge and ionized acceptors at the surface. The difference in surface stoichiometry in these two orientations is responsible for the different behavior in electrical characteristics after gamma-ray interactions.
Modeling and improvement of a low-frequency micro-accelerometer
Authors: Cheng Z. Y. , Liu L. Y. , Lei Y. J. , Li H. L. , Zhang L. S. , Li R. J. , Huang Q. X.
Published: February 2021

A sensitivity- and resolution-improving method for a low-frequency micro-vibration accelerometer is presented in this paper. A sensitivity model of the measurement system is derived and established. The key parameters that limit the sensitivity and the resolution of the accelerometer were identified through the sensitivity coefficient analysis method. The structural parameters and the signal process method were then optimized. Experimental results show that the sensitivity of the accelerometer has improved from 1.10 V/(m/s2) to 19.21 V/(m/s2), and the resolution has improved from 1.47 mm/s2 to 0.21 mm/s2. The lowest working frequency range has expanded from 1 Hz to 0.7 Hz. The presented method is effective and cheap and can be applied to other sensors.
The rheology of direct and suspended extrusion bioprinting
Authors: Cooke Megan E. , Rosenzweig Derek H.
Published: February 2021

Bioprinting is a tool increasingly used in tissue engineering laboratories around the world. As an extension to classic tissue engineering, it enables high levels of control over the spatial deposition of cells, materials, and other factors. It is a field with huge promise for the production of implantable tissues and even organs, but the availability of functional bioinks is a barrier to success. Extrusion bioprinting is the most commonly used technique, where high-viscosity solutions of materials and cells are required to ensure good shape fidelity of the printed tissue construct. This is contradictory to hydrogels used in tissue engineering, which are generally of low viscosity prior to cross-linking to ensure cell viability, making them not directly translatable to bioprinting. This review provides an overview of the important rheological parameters for bioinks and methods to assess printability, as well as the effect of bioink rheology on cell viability. Developments over the last five years in bioink formulations and the use of suspended printing to overcome rheological limitations are then discussed.
Effects of system rotation on diffusion of the disturbances in inhomogeneous strongly stratified flow
Authors: Iida Oaki
Published: February 2021

This study is an extension of our previous study [O. Iida, “Turbulent structure of stably stratified inhomogeneous flow,” Phys. Fluids 30, 045101 (2018)] where direct numerical simulations of a spectral method are performed for an inhomogeneous flow under stable density stratification by the inclusion of a fringe region where an artificial body force is imposed to make the flow locally disturbed, and thus, generated disturbances are horizontally diffused into the undisturbed laminar region. In this study, moreover, additional effects of system rotation on diffused disturbances are investigated in detail. As a result, we find that rotation makes the horizontally diffused disturbances anticyclonic vortices and that with a further increase in rotation, the horizontal diffusion is significantly attenuated, and their horizontal and vertical lengths decrease and increase, respectively. In addition, it is found that attenuating the energy cascade in the vertical direction simultaneously attenuates the horizontal enlargement of anticyclonic vortices.
Quasi-periodic selective multilayer emitter for sub-ambient daytime radiative cooling
Authors: Zhu Yeqing , Ye Yong-Hong , Wang Dong , Cao Yurong
Published: February 2021

This work theoretically demonstrates a quasi-periodic selective multilayer emitter for sub-ambient daytime radiative cooling. In the design process, by inserting well-defined materials with different refractive-index profiles in suitable layers, there are absorption bands at different regions and the absorption bands are enhanced and broad in atmospheric transparency windows. Combined with the interference effects of the surface and the high reflectivity of Ag, the solar reflectance of the emitter is maximal in the solar spectrum. The influence of different nonradiative heat exchanges and the ambient air temperatures on the cooling performance of the multilayer emitter are calculated. At the same time, the mechanism of radiative cooling is analyzed. All the results show that the proposed emitter can effectively achieve sub-ambient daytime radiative cooling. Due to the superior durability and mechanical robustness of the multilayer emitter, it may be a key element in the realization of energy-efficient radiative cooling devices.
Superelastic behavior of single crystalline Ni48Fe20Co5Ga27 micro-pillars near austenite–martensite critical point
Authors: Chang T.-F. M. , Chernenko V. , Tang H.-C. , Chen C.-Y. , Umise A. , Tahara M. , Hosoda H. , Sone M.
Published: February 2021

Micro-pillars oriented in austenite along [100], [110], and [111] crystallographic directions were fabricated on the corresponding edges of a single crystalline plate of the Ni48Fe20Co5Ga27 magnetic shape memory alloy exhibiting martensitic transformation (MT) at 150 K. Superelastic behavior of pillars, due to micro-compression-induced MT, was investigated at different temperatures from 298 K to 373 K. At room temperature, Young’s moduli of the [100], [110], and [111] pillars in austenite are equal to 5.3 GPa, 7.9 GPa, and 9.9 GPa, respectively, resulting in the linear dependences of the elastic strain reaching up to the record-breaking value of 10%. On increasing temperature, the stress–strain dependencies exhibit changes that are interpreted in terms of the critical behavior on approaching to the end points on the martensite–austenite stress–temperature phase diagrams.
Flow developing properties of a compressible parallel jet
Authors: Liu Qilin , Lai Huanxin
Published: February 2021

Two-point space–time correlation and Fourier spectrum analysis are applied to large-eddy simulation results of a compressible parallel jet flow at Reynolds number 2000 and Mach number 0.9. Flow properties including instantaneous vortical structures, flow intermittency, convection velocity of vortical structures, and pressure signals in the near flow-field are presented and discussed. The results show multi-scale features of vortical structures after flow transition. High intermittency is found to occur around the outer edges of the shear layer and the region surrounding the potential core, where the motion of vortices is vigorous. In order to analyze the motion of vortices, the convection velocity of vortical structures in the center plane of the jet is calculated by a designed solution procedure. The high convection velocity zone is shown to be a “V” shaped cap covering the potential core. The pressure fluctuation signals in the vortical flow are analyzed so as to study the effects of vortex motion. The signals show the feature of wave-packets and contain multiple dominant frequencies. The distribution of the dominant frequencies is characterized by a terrace shaped zone with stairs descending in both the streamwise and lateral directions. In addition, the phase velocity of the pressure signals shown by the frequency–wavenumber diagram unveils that the pressure fluctuations travel at a stable phase velocity along the lip-line of the jet, while the component with a supersonic phase velocity is salient in the downstream of the flow transition region outside the shear layer.
Jetting behavior as a bubble bursts in free space
Authors: Wang Ziyue , Duan Runze , Liu Liansheng , Yang Hua
Published: February 2021

The phenomenon of bubble bursting is very common in nature and is of prime importance in various technologies and industrial processes. Similar to interfacial bubbles, the process of a bubble bursting in free space, that is, the rupture of bubbles surrounded by air, often results in jet flows. However, the location and mechanism of the jet flows are different from those produced by interfacial bubbles. This paper describes the results of several experiments conducted to investigate the behavior of a bubble bursting in free space, especially the jet flows that occur at the end of the process. The results show that viscosity has a strong inhibitory effect on both the droplets (film drops and jet drops) and the jet resulting from bubble bursting. Based on experimental results, we establish a phase diagram for the jetting behavior in terms of the Reynolds number (Re) and the Ohnesorge number (Oh) and discover the existence of threshold conditions. Jetting occurs in the zone where Oh is less than some threshold value Ohc and Re is greater than some threshold value Rec, whereas a liquid clump appears in the zone where Oh > Ohc and Re < Rec. For 0.002 < Oh < 0.272 and 65 < Re < 52 633, we find that Rec = 503 ± 136 and Ohc = 0.079 ± 0.001. A schematic of the events that occur during bubble bursting depicting the forces at play is subsequently analyzed, and the role of viscosity at the moment of jetting is highlighted. The results of this study can be used to inhibit or increase the formation of droplets in numerous applications.
Ion-cut lithium niobate on insulator technology: Recent advances and perspectives
Authors: Jia Yuechen , Wang Lei , Chen Feng
Published: February 2021

Lithium niobate (LiNbO3 or LN) is a well-known multifunctional crystal that has been widely applied in various areas of photonics, electronics, and optoelectronics. In the past decade, “ion-cut” has become the key technique to produce wafer-size, high-quality, sub micrometer-thickness crystalline LiNbO3 thin films, i.e., lithium-niobate-on-insulator (LNOI). With the rapid development of LNOI technology and the tremendous progress of associated surface structuring and engineering techniques over the last few years, many novel chip-integrated LiNbO3-based devices and applications with reduced cost, complexity, power, and size, are demonstrated, boosting the resurgence of integrated photonics based on this material. The remarkable achievements are largely facilitated by the most recent technological progress in photonic integration and performance optimization of LNOI on-chip devices, such as high-quality surface domain engineering, advanced heterogeneous integration technology, powerful dispersion engineering, fine polishing lithography, and wafer-scale fabrication. Accordingly, batch-compatible chip-integrated platforms for more complex photonic integrated circuits, such as quantum optical circuits, are within reach. This article provides a timely review of the key advances in LNOI technology and a reasonable perspective on the near-future directions for both integrated photonics and applied physics communities.
Rate constants for the H+ + H2 reaction from 5 K to 3000 K with a statistical quantum method
Authors: González-Lezana Tomás , Hily-Blant Pierre , Faure Alexandre
Published: February 2021

An exhaustive investigation of state-to-state H+ + H2(v, j) → H+ + H2(v′, j′) transitions for rovibrational levels of molecular hydrogen below 1.3 eV from the bottom of the H2 well is carried out by means of a statistical quantum method, which assumes the complex-forming nature of the process. Integral cross sections for transitions involving states H2(v = 0, j = 0–12), H2(v = 1, j = 0–8), and H2(v = 2, j = 0–3) are obtained for collision energies within a range of Emin = 10−5 eV and Emax = 2 eV. Rate constants are then calculated between T = 5 K and 3000 K, and they are compared, when possible, with previous values reported in the literature. As a first application, the cooling rate coefficient of H2 excited by protons is determined and compared with a recent estimate.
W thickness dependence of spin Hall effect for (W/Hf)-multilayer electrode/CoFeB/MgO systems with flat and highly (100) oriented MgO layer
Authors: Saito Yoshiaki , Tezuka Nobuki , Ikeda Shoji , Endoh Tetsuo
Published: February 2021

We investigated spin-Hall effect (SHE) and degree of MgO (100) orientation in artificially synthesized (W/Hf)-multilayer/CoFeB/MgO systems with various W thicknesses. We found that the artificially synthesized multilayer systems can enhance the spin-Hall effect and control the value of spin diffusion length. We observed a maximum magnitude in both spin-Hall angle and spin-Hall conductivity as a function of W thickness in W/Hf-multilayer systems, and found that the values of spin-Hall conductivity are larger than that for β-phase W. In addition, a more highly oriented MgO (100) texture on CoFeB is obtained for (W/Hf)-multilayer systems prepared under low-Ar-pressure condition, which would be suitable for preparation of magnetic tunnel junctions with high tunnel magnetoresistance properties on (W/Hf)-multilayer heavy metal electrode. These results suggest that the artificially synthesized multilayer system is one of the avenues for realizing spin devices using spin-orbit torque.
Social distancing decreases an individual’s likelihood of contracting COVID-19
Authors: Fazio Russell H. , Ruisch Benjamin C. , Moore Courtney A. , Granados Samayoa Javier A. , Boggs Shelby T. , Ladanyi Jesse T.
Published: February 2021

Significance

Previous work establishes the effectiveness of social distancing for reducing COVID-19 transmission at the aggregate level: Locales in which restrictions were imposed experienced a reduction in spread of the virus. However, we know little about the effectiveness of social distancing at the level of the individual. Do individuals who engage in social distancing reduce their personal likelihood of contracting COVID-19? Or are these effects only evident in the aggregate? A longitudinal investigation involving 2,120 online participants demonstrated that individual differences matter. Participants who exhibited greater social distancing on a virtual behavior measure—simulations presenting graphical depictions of specific real-world scenarios, asking them to position themselves relative to others in the scene—were less likely to contract COVID-19 subsequently.
(No) variation in the grammar of alternatives
Authors: Howell Anna , Hohaus Vera , Berezovskaya Polina , Sachs Konstantin , Braun Julia , Durmaz Şehriban , Beck Sigrid
Published: February 2021

The paper reports the results of an in-depth crosslinguistic study of intervention effects and the grammar of alternatives in a typologically diverse sample of five languages: Palestinian Arabic (Afro-Asiatic, Semitic), Russian (Indo-European, Slavic), Samoan (Austronesian, Oceanic), Turkish (Altaic, Turkic), and Yoruba (Niger-Congo, Defoid). In all of these languages, we find an interesting asymmetry in that focus evaluation interrupts question evaluation and causes an intervention effect, but not vice versa. We take our data to inform the crosslinguistic analysis of two alternative-evaluating operators, the squiggle operator and the question operator. To capture the observed absence of variation, we propose two semantic universals: The squiggle operator unselectively evaluates all alternatives in its scope. The question operator, on the other hand, is selective.
Zinc supplementation in ruminant diets: efficacy, safety, and formulation
Authors: Robles Jimenez Lizbeth E. , Rodríguez Maya Mario Alberto , Aranda-Aguirre Edgar , Castañon Marta Miranda , Dominguez Vara Ignacio A , Bello-Pérez Einar Vargas- , Manuel González Ronquillo
Published: February 2021

Zinc (Zn) is a micro mineral with catalytic regulatory and structural functions in muscle tissue. It increases growth in ruminants because it modulates energy metabolism. It participates in the metabolism of proteins and nucleic acids; it stimulates the activity of approximately 100 enzymes and contributes to the proper functioning of the immune system. The use of different sources of Zn in ruminant diets has increased in recent years. Because of the human healthy living trend, dietary supplement alternatives have grown fast in ruminant production. In this sense, dietary Zn has a potential to enhance antiviral immunity, both innate and humoral, and to restore depleted immune cell function or to improve normal immune cell function. In addition, Zn supplementation improves weight gain and reproductive parameters in ruminants. The objective of this review was to update current knowledge on Zn in ruminant diets from intake to excretion.
Dynamics of a two scalar field cosmological model with phantom terms
Authors: Paliathanasis Andronikos , Leon Genly
Published: February 2021

We perform a detailed analysis of the dynamics of a chiral-like cosmological model where the scalar fields can have negative kinetic terms. In particular, we study the asymptotic dynamics for the gravitational field equations for four different models in a spatially flat Friedmann–Lemaître–Robertson–Walker (FLRW) background space. When one of the scalar fields is phantom, we show that the cosmological fluid can evolves such that the parameter of the equation of state crosses twice the phantom divide line without the appearance of ghosts. Moreover, the cosmological viability of these four models is discussed.
Dual wideband, polarization, angle-insensitive diffusion electromagnetic surfaces for radar cross section reduction
Authors: Yu Hang , Su Jianxun , Guo Qingxin , Li Zengrui
Published: February 2021

In this paper, we introduce an effective technique for designing diffusion electromagnetic (EM) surfaces with polarization and angle-insensitive characteristics over multiple wide bands. The proposed EM surface consists of a random pixelated metal structure in the middle of double substrate layers and a metallic ground at the bottom. Phase cancellation for radar cross section (RCS) reduction is achieved by different propagation paths generated by the pixelated metallic layer. The theoretical prediction of the reduction frequency band and reduction value is derived by transmission line theory, which serves as guidance to design the EM surface for the required operating band. Using this technique, an EM surface is designed for 10 dB RCS reduction over multiple frequency bands, and the first two reduction bands are 5.98–16.23 GHz and 26.69–37.1 GHz with fractional bandwidths of 92.3% and 32.6%, respectively. The non-reduction frequency band between the first two reduction bands is almost at the K-band (18–27 GHz), which is unusable for long-range transmission because of its high atmospheric loss. Moreover, the bandwidth of RCS reduction bands is stable for oblique incident angles up to 40° for both TE and TM polarizations. Based on theoretical study and simulation results, a prototype of this EM surface is fabricated and experimentally characterized. The theoretical analysis, simulation and experiment results are in good agreement. The proposed method comprehensively solves the problems of narrow bandwidth, time-consuming optimization of the unit cell, high bistatic RCS value, and sensitivity to polarization and incident angles found in recent RCS reduction research.
Comparative role of the 7Li(n,
γ
) reaction in Big Bang nucleosynthesis
Authors: Burkovа N A , Dubovichenkо S B , Dzhazairov-Kakhramanov А V , Nurakhmetova S Z
Published: February 2021

Within the framework of the modified potential cluster model with forbidden states and their classification according to Young diagrams, the possibility of describing experimental data on the total cross sections of the neutron radiative capture on 7Li is considered. It is shown that the model used and the methods for constructing potentials make it possible to correctly describe the behavior of experimental cross sections at energies of 1 meV to 1.5 MeV, where experimental data are available. Based on the calculated total cross sections up to 5 MeV, the reaction rate is calculated and its analytical approximation is carried out. Resonance structure of 7Li(n, γ)8Li cross section and its impact on the reaction rate is examined. It is shown that the 7Li(n, γ)8Li reaction dominates at T
9 < 0.1 as opposed to the burning of 7Li in the 7Li(3H, n)9Be and 7Li(4Нe, γ)11B reactions, but comparable to (d, γ), (d, p), and (p, γ) at T
9 ∼ 1.
A set of student activities for the simulation of ancient and medieval astronomical observations
Authors: Spathopoulos Vassilios McInnes
Published: February 2021

A set of student activities is presented based on astronomical observations made by ancient and medieval astronomers. The activities are implemented using freeware planetarium software and can be accessed by astronomy educators or anyone with an interest in the history of astronomy. The use of planetarium software offers a unique possibility to reproduce landmark observations in a fun and interactive way.
Generalizable cone beam CT esophagus segmentation using physics-based data augmentation
Authors: Alam Sadegh R , Li Tianfang , Zhang Pengpeng , Zhang Si-Yuan , Nadeem Saad
Published: February 2021

Automated segmentation of the esophagus is critical in image-guided/adaptive radiotherapy of lung cancer to minimize radiation-induced toxicities such as acute esophagitis. We have developed a semantic physics-based data augmentation method for segmenting the esophagus in both planning CT (pCT) and cone beam CT (CBCT) using 3D convolutional neural networks. One hundred and ninety-one cases with their pCTs and CBCTs from four independent datasets were used to train a modified 3D U-Net architecture and a multi-objective loss function specifically designed for soft-tissue organs such as the esophagus. Scatter artifacts and noises were extracted from week-1 CBCTs using a power-law adaptive histogram equalization method and induced to the corresponding pCT were reconstructed using CBCT reconstruction parameters. Moreover, we leveraged physics-based artifact induction in pCTs to drive the esophagus segmentation in real weekly CBCTs. Segmentations were evaluated using the geometric Dice coefficient and Hausdorff distance as well as dosimetrically using mean esophagus dose and D
5cc. Due to the physics-based data augmentation, our model trained just on the synthetic CBCTs was robust and generalizable enough to also produce state-of-the-art results on the pCTs and CBCTs, achieving Dice overlaps of 0.81 and 0.74, respectively. It is concluded that our physics-based data augmentation spans the realistic noise/artifact spectrum across patient CBCT/pCT data and can generalize well across modalities, eventually improving the accuracy of treatment setup and response analysis.
A DFT based first-principles investigation of optoelectronic and structural properties of Bi2Te2Se
Authors: Afzal Md Asif , Naqib S H
Published: February 2021

Bi2Te2Se is a topological insulator (TI) having conducting surface electronic states with an energy gap in the bulk electronic band structure. Such systems are promising for variety of superconducting and quantum computation related applications. In addition, TIs may possess other important bulk physical characteristics appropriate for more conventional applications which are not affected significantly by spin–orbit interaction. In this study we focus on bulk properties of Bi2Te2Se which are not greatly affected by the surface electronic states and therefore, by spin–orbit coupling. We have investigated elastic, mechanical, electronic, optical properties, bonding character and the electronic charge density distribution of ternary Bi2Te2Se to explore its feasibility for potential applications. Bi2Te2Se is found to be mechanically stable and elastically anisotropic. Electronic effective mass is high in the c-direction compared to that in the ab-plane. The optical constants show moderate level of variation with respect to the polarization of the electric field of the incident radiation. The optical spectra are consistent with the bulk electronic band structure and electronic density of states features. Both electronic band structure and optical constants show clear indications of a direct band gap of 0.61 eV for Bi2Te2Se. Bi2Te2Se possesses high refractive index at low photon energies in the infrared and visible region. It has low reflectivity in the ultraviolet region. Bi2Te2Se absorbs photons strongly in the ultraviolet energies. All these characteristics make Bi2Te2Se suitable for diverse class of optoelectronic device applications.