bluuebunny/crossref_metadata_2025 huggingface dataset:
Design of surface termination for high-performance perovskite solar cells
Authors: Yang Yan , Zhao Wangen , Yang Tengteng , Liu Jiali , Zhang Jingru , Fang Yuankun , Liu Shengzhong (Frank)
Published: September 2021

Guanidinium thiocyanate was selected to modify the surface terminations of methylamine lead iodide (MAPbI3) perovskite films and a 21.26% PCE was acquired for a solar cell based on the MAPbI3 system, and the voltage deficit is reduced to 0.426 V.
Doping of graphene via adlayer formation of electrochemically reduced dibenzyl viologen
Authors: Huynh Thi Mien Trung , Phan Thanh Hai , Phillipson Roald , Volodine Alexander , De Feyter Steven
Published: September 2021

Doping of graphene by self-assembled molecular network of uncharged dibenzyl viologen (DBV0) generated in situ.
Effects of polarized light on the optical and self-oscillation behaviors of liquid crystal network polymers
Authors: Zibaei Rana , Zakerhamidi Mohammad Sadegh , Korram Sirous , Ranjkesh Amid
Published: September 2021

The different polarizations of light show different oscillating behaviors in terms of amplitude and frequency of the LCN oscillation.
An S-shaped thienoacene semiconductor forming unique cruciform lamellar packing via a 2D interaction network of π-stacking and chalcogen bonding
Authors: Mori Tatsuya , Yamaguchi Yuji , Kawata So , Yasuda Takuma
Published: September 2021

A crooked S-shaped thienoacene adopts a unique lamellar packing with an orthogonally arranged cruciform molecular array. The 2D interaction network of π-stacking and chalcogen bonding contributes to efficient hole transport.
Shared Interactive Book Reading Interventions for Young Children With Disabilities: A Systematic Review
Authors: Towson Jacqueline A. , Akemoglu Yusuf , Watkins Laci , Zeng Songtian
Published: September 2021

Purpose

Shared interactive book reading (SIBR) is an evidence-based practice for young children who are typically developing and those with developmental disabilities or considered at risk for developmental delays. The purpose of this review was to provide a comprehensive examination of the evidence of using SIBR to facilitate growth in language skills for young children with developmental disabilities and/or delays. Specifically, authors examined the descriptive characteristics, study rigor, and effect sizes for language and literacy outcomes.

Method

We extracted data from studies meeting specified criteria (
n
= 23) published in peer-reviewed journals on a wide range of variables, including participant characteristics, setting, training/coaching, defined independent and dependent variables, study rigor, and overall outcomes. Descriptive and study rigor data were aggregated using descriptive statistics. Effect-size estimates were calculated for all child outcomes related to language.

Results

Descriptive data were variable across studies. Three single-case experimental design and three group design studies met design standards without reservations. Single-case experimental design studies overall showed positive effects on child language and communication. Within group design studies, expressive language outcomes showed the largest effect sizes.

Conclusion

A review of SIBR studies indicates this as a viable intervention to positively impact the language skills of young children with developmental disabilities and/or delays.

Supplemental Material

https://doi.org/10.23641/asha.16674355
Measurement of Social Engagement of Nursing Home Residents During an Exercise Program
Authors: Neils-Strunjas Jean , Crandall K. Jason , Weiler Brian , Gabbard Annika , Wood Caroline , Ding Xiuhua
Published: September 2021

Purpose

The purpose of this article was to describe the validity and reliability of the Fun and Social Engagement Evaluation (FUSE) developed to evaluate and measure social engagement displayed by nursing home residents during Bingocize. The FUSE combines health care worker observation and a resident self-report measure to produce a score that represents a resident's total engagement.

Method

To describe validity, trained health care workers who implement Bingocize were surveyed about the items on the FUSE. Visual inspection of bar graphs of responses to survey questions were used to determine content validity.

To assess reliability of the FUSE, nursing home residents were evaluated by trained research assistants. Test–retest reliability of the participant scores 1 week apart was determined with the bivariate correlation (Pearson product–moment correlation coefficient).

Results

For validity, the majority of survey respondents indicated that the behaviors were representative of nursing home residents during Bingocize. For reliability, there was moderate–strong test–retest reliability over 1 week (
r
= .60). Interrater reliability between two raters observing eight participants across two sessions was significant, κ = .68 (95% CI [.504,.848]),
p
< .0001.

Conclusion

Results offer evidence that the FUSE is a valid and reliable method for determining social engagement during Bingocize.
On‐line dead‐time compensation method for dual three phase PMSM based on adaptive notch filter
Authors: Geng Yiwen , Han Peng , Chen Xiang , Chen Ruicheng , Le Zitao , Lai Zou
Published: September 2021

For the dual three‐phase permanent magnet synchronous motor(dual‐PMSM), the deadtime can introduce fifth and seventh current harmonics, and they are only constrained by the small stator leakage impedance, which means even if there are only small fifth and seventh voltage harmonics, the resulting fifth and seventh current harmonics will be very large. The harmonic current will make an increment of the system loss, thus lead to an reduce of the efficiency of the speed control system. This paper proposes a harmonic current suppression strategy for dual‐PMSM based on least mean square (LMS) adaptive notch filter. This strategy suppresses the fifth and seventh harmonic currents by introducing four LMS adaptive notch filters in the subspace. The proposed algorithm has good dynamic performance and is insensitive to motor parameters that are offset within a certain range. The effectiveness of proposed method is verified by a set of comparative simulations and experiments.
Gas-phase formation of interstellar nucleobases from dehydrogenated formamide and vinyl cyanide
Authors: Lu Shiru , Meng Zhisen , Xie Peng , Liang Enwei , Wang Zhao
Published: September 2021

Context. Cytosine, thymine, and uracil are three of the five primary nucleobases that function as the fundamental units of the genetic code in nucleic acids. In searching the extraterrestrial origins of microscopic life, previous studies have reported formation routes of nucleobases in interstellar ice analogs. The present work explores the possibility that nucleobases could form from small molecules through gas-phase reactions in the interstellar medium (ISM).

Aims. We aim to search energetically favorable synthetic routes toward the formation of cytosine, thymine, and uracil via gas-phase reactions, using first principles calculations. Based on the computation of a reaction energy barrier and reactant formation energy, we tried to identify the specific interstellar environments favorable to the formation of the nucleobases, with respect to the previously reported detection of relevant reactants in the ISM.

Methods. Density functional theory calculations were carried out to investigate the chemical reaction pathways using the M06 functional with 6-31+G(d,p)/6-311++G(d,p) basis sets. An ab initio Møller-Plesset perturbation theory in the second order (MP2) was also used to corroborate the results.

Results. We report synthetic routes toward the formation of cytosine, thymine, and uracil through gas-phase reactions between partially dehydrogenated formamide (H2NCHO) and vinyl cyanide (H2CCHCN). The most energetically favorable pathway to the formation of 1H-pyrimidin-2-one (C4H4N2O), a direct precursor of nucleobases, was found in a molecule-radical reaction between HNCHO and H2CCHCN, with an energy barrier of 19.3 kcal mol−1. The energy barriers for the optimal reaction pathways between C4H4N2O and amino, methyl, or hydroxyl to finally produce cytosine, thymine, or uracil are about 11.3, 18.6, or 19.9 kcal mol−1, respectively.

Conclusions. The optimal energy barriers of 19.3 and 23.8 kcal mol−1 roughly correspond to a reaction rate coefficient of 10−11 cm3 s−1 at 180 and 220 K, respectively. This indicates that the reaction could be thermally feasible through a gas-phase reaction in hot molecular cores or in the inner part of the protoplanetary disks. In contrast, the energy barriers for the reactions between other dehydrogenated radicals and molecules are relatively high, which corresponds to the extinction energy of far-ultraviolet photons in photo-dissociation regions. Furthermore, the computed pathways suggest that prior H migration in the reactants could be the key rate-determining process for the synthesis of the primary nucleobases.
The Sun at millimeter wavelengths
Authors: Eklund Henrik , Wedemeyer Sven , Szydlarski Mikołaj , Jafarzadeh Shahin
Published: September 2021

Context. Interferometric observations of the Sun with the Atacama Large Millimeter/sub-millimeter Array (ALMA) provide valuable diagnostic tools for studying the small-scale dynamics of the solar atmosphere.

Aims. The aims are to perform estimations of the observability of the small-scale dynamics as a function of spatial resolution for regions with different characteristic magnetic field topology facilitate a more robust analysis of ALMA observations of the Sun.

Methods. A three-dimensional model of the solar atmosphere from the radiation-magnetohydrodynamic code Bifrost was used to produce high-cadence observables at millimeter and submillimeter wavelengths. The synthetic observables for receiver bands 3–10 were degraded to the angular resolution corresponding to ALMA observations with different configurations of the interferometric array from the most compact, C1, to the more extended, C7. The observability of the small-scale dynamics was analyzed in each case. The analysis was thus also performed for receiver bands and resolutions that are not commissioned so far for solar observations as a means for predicting the potential of future capabilities.

Results. The minimum resolution required to study the typical small spatial scales in the solar chromosphere depends on the characteristic properties of the target region. Here, a range from quiet Sun to enhanced network loops is considered. Limited spatial resolution affects the observable signatures of dynamic small-scale brightening events in the form of reduced brightness temperature amplitudes, potentially leaving them undetectable, and even shifts in the times at which the peaks occur of up to tens of seconds. Conversion factors between the observable brightness amplitude and the original amplitude in the fully resolved simulation are provided that can be applied to observational data in principle, but are subject to wavelength-dependent uncertainties. Predictions of the typical appearance at the different combinations of receiver band, array configuration, and properties of the target region are conducted.

Conclusions. The simulation results demonstrate the high scientific potential that ALMA already has with the currently offered capabilities for solar observations. For the study of small-scale dynamic events, however, the spatial resolution is still crucial, and wide array configurations are preferable. In any case, it is essential to take the effects due to limited spatial resolution into account in the analysis of observational data. Finally, the further development of observing capabilities including wider array configurations and advanced imaging procedures yields a high potential for future ALMA observations of the Sun.
Gas-phase laboratory formation of large, astronomically relevant PAH-organic molecule clusters
Authors: Hu Xiaoyi , Yang Yuanyuan , Zhang Congcong , Chen Yang , Zhen Junfeng , Qin Liping
Published: September 2021

Polycyclic aromatic hydrocarbon (PAH) molecules may play an essential role in the prebiotic compound evolution network in interstellar clouds. In this work, an experimental study of large, astronomically relevant PAH-organic molecule clusters is presented. With the initial molecular precursors dicoronylene (DC; C48H20)-pyroglutamic acid (Pga, C5H7NO3), DC-proline (Pro; C5H9NO2), and DC-pyroglutaminol (Pgn; C5H9NO2), our experiments indicate that PAH–organic molecule cluster cations (e.g., (Pga)(1−2)C48Hn+, (Pro)(1−2)C48Hn+, and (Pgn)(1−6)C48Hn+) and carbon cluster–organic molecule cluster cations (e.g., (Pga)C48+, (Pro)(1−2)C48+, and (Pgn)(1−6)C48+) are gradually formed through an ion-molecule collision reaction pathway in the presence of a strong galactic interstellar radiation field. These laboratory studies provide a gas-phase growth route toward the formation of complex prebiotic compounds in a bottom-up growth process, as well as insight into their chemical-evolution behavior in the interstellar medium.
Towards a systematic treatment of observational uncertainties in forward asteroseismic modelling of gravity-mode pulsators
Authors: Bowman Dominic M. , Michielsen Mathias
Published: September 2021

Context.In asteroseismology, the pulsation mode frequencies of a star are the fundamental data that are compared to theoretical predictions to determine a star’s interior physics. Recent significant advances in the numerical, theoretical, and statistical asteroseismic methods applied to main-sequence stars with convective cores have renewed interest in investigating the propagation of observational uncertainties within a forward asteroseismic modelling framework.

Aims.We aim to quantify the impact of various choices made throughout the observational aspects of extracting pulsation mode frequencies in main-sequence stars with gravity modes.

Methods.We use a well-studied benchmark slowly pulsating B star, KIC 7760680, to investigate the sensitivity of forward asteroseismic modelling to various sources of observational uncertainty that affect the precision of the input pulsation mode frequencies.

Results.We quantify the impact of the propagation of the observational uncertainties involved in forward asteroseismic modelling. We find that one of the largest sources of uncertainty in our benchmark star is in the manual building of period spacing patterns, such that the inclusion of a potentially ambiguous pulsation mode frequency may yield differences in model parameters of up to 10% for mass and age depending on the radial order of the mode.

Conclusions.We conclude that future asteroseismic studies of main-sequence stars with a convective core should quantify and include observational uncertainties introduced by the light curve extraction, iterative pre-whitening, and the building of period spacing patterns, as these propagate into the final modelling results.
Nebular phase properties of supernova Ibc from He-star explosions
Authors: Dessart L. , Hillier D. J. , Sukhbold T. , Woosley S. E. , Janka H.-T.
Published: September 2021

Following our recent work on Type II supernovae (SNe), we present a set of 1D nonlocal thermodynamic equilibrium radiative transfer calculations for nebular-phase Type Ibc SNe starting from state-of-the-art explosion models with detailed nucleosynthesis. Our grid of progenitor models is derived from He stars that were subsequently evolved under the influence of wind mass loss. These He stars, which most likely form through binary mass exchange, synthesize less oxygen than their single-star counterparts with the same zero-age main sequence (ZAMS) mass. This reduction is greater in He-star models evolved with an enhanced mass loss rate. We obtain a wide range of spectral properties at 200 d. In models from He stars with an initial mass > 6 M⊙, the [O I] λλ 6300,  6364 is of a comparable or greater strength than [Ca II] λλ 7291,  7323 – the strength of [O I] λλ 6300,  6364 increases with the He-star initial mass. In contrast, models from lower mass He stars exhibit a weak [O I] λλ 6300,  6364, strong [Ca II] λλ 7291,  7323, and also strong N II lines and Fe II emission below 5500 Å. The ejecta density, which is modulated by the ejecta mass, the explosion energy, and clumping, has a critical impact on gas ionization, line cooling, and spectral properties. We note that Fe II dominates the emission below 5500 Å and is stronger at earlier nebular epochs. It ebbs as the SN ages, while the fractional flux in [O I] λλ 6300,  6364 and [Ca II] λλ 7291,  7323 increases with a similar rate as the ejecta recombine. Although the results depend on the adopted wind mass loss rate and pre-SN mass, we find that He-stars of 6–8 M⊙ initially (ZAMS mass of 23–28 M⊙) match the properties of standard SNe Ibc adequately. This finding agrees with the offset in progenitor masses inferred from the environments of SNe Ibc relative to SNe II. Our results for less massive He stars are more perplexing since the predicted spectra are not seen in nature. They may be missed by current surveys or associated with Type Ibn SNe in which interaction power dominates over decay power.
Riesz Basis Property and Exponential Stability for One-Dimensional Thermoelastic System with Variable Coefficients
Authors: Guo Bao-Zhu , Ren Han-Jing
Published: September 2021

In this paper, we study Riesz basis property and stability for a nonuniform thermoelastic system with Dirichlet-Dirichlet boundary condition, where the heat subsystem is considered as a control to the whole coupled system. By means of the matrix operator pencil method, we obtain the asymptotic expressions of the eigenpairs, which are exactly coincident to the constant coefficients case. We then show that there exists a sequence of generalized eigenfunctions of the system, which forms a Riesz basis for the state space and the spectrum determined growth condition is therefore proved. As a consequence, the exponential stability of the system is concluded.
Konzeption von Frequently Asked Questions zum Umgang mit
multiresistenten Erregern an der Schnittstelle von Veterinär- und
Humanmedizin
Authors: Landesberger Valeria , Kutzora Susanne , Fritzemeier Jörg , Hörmansdorfer Stefan , Köck Robin , Teichert Ute , Kandler Ulla , Wischnewski Nicoletta , Herr CarolineEvaWella , Heinze Stefanie
Published: September 2021

Ziel Ziel der Arbeit ist die systematische und evidenzbasierte Generierung
und Beantwortung von Frequently asked questions (FAQs) zum Umgang mit
multiresistenten Erregern (MRE) an der Schnittstelle von Veterinär-und
Humanmedizin für den öffentlichen Gesundheitsdienst
(ÖGD) sowie für die Allgemeinbevölkerung.

Methodik Zur Ermittlung des Informationsbedürfnisses der
Bevölkerung wurden zu fünf Erhebungszeitpunkten
leitfadengestützte Experteninterviews mit Veterinär-und
Humanmedizinern durchgeführt. Zusätzlich wurden in zwei
Fachzeitschriften über das Projekt informiert sowie Mediziner dazu
aufgerufen offene Fragen aus dem Arbeitsalltag zum Umgang mit Tieren
hinsichtlich MRE, einzureichen. Die. Ergebnisse der Interviews und
Projektaufrufe wurden in Kategorien gegliedert und häufig genannte
Themen wurden als FAQs aufbereitet. Die Beantwortung der FAQs erfolgte mit einer
systematischen Literaturrecherche in den Datenbanken Pubmed und Wiley Online
Library. Innerhalb eines Expertengremiums wurden die FAQ-Entwürfe
anschließend diskutiert und bei widersprüchlichem
Forschungsstand ein Konsens erarbeitet. Im Anschluss wurden die FAQs von
Humanmedizinern des ÖGD evaluiert.

Ergebnisse Insgesamt wurden neun FAQs generiert. Neben dem Stand der
Forschung, wurden Empfehlungen für den privaten, nicht-medizinischen
Umgang mit MRE an der Schnittstelle von Human-und Veterinärmedizin
ausgesprochen. Die Empfehlungen sind abhängig von den Eigenschaften des
jeweiligen Settings, bei dem Menschen und Tiere aufeinandertreffen sowie der Art
des Tierkontakts. So wurden unterschiedliche Empfehlungen für den Umgang
mit MRE bei Heimtieren, bei Nutztieren, bei Tieren in
Gemeinschaftseinrichtungen, sowie bei Therapietieren ausgesprochen. Als
wichtigste Maßnahme gegen eine Verbreitung von MRE zwischen Menschen und
Tieren hat sich das regelmäßige und sorgfältige
Händewaschen erwiesen.

Schlussfolgerung Um die Qualität der FAQs gewährleisten zu
können, wurden diese multimodal generiert und beantwortet.
Einschränkungen in der Qualität zeigten sich bei der
Literaturrecherche. Nicht alle eingereichten Themenbereiche konnten mit der zur
Verfügung stehenden Literatur bearbeitet werden. In der Zukunft sollten
die FAQs kontinuierlich aktualisiert und erweitert werden.
An Endoscopic Endonasal Nasopharyngectomy with Posterolateral Extension
Authors: Li Lifeng , London Nyall R. , Prevedello Daniel M. , Carrau Ricardo L.
Published: September 2021

Background Invasion depth influences the choice for extirpation of nasopharyngeal malignancies. This study aims to validate the feasibility of endoscopic endonasal resection of lesions with a posterolateral invasion. As a secondary goal, the study intends to propose a classification system of endoscopic endonasal nasopharyngectomy determined by the depth of posterolateral invasion.

Methods Eight cadaveric specimens (16 sides) underwent progressive nasopharyngectomy using an endoscopic endonasal approach. Resection of the torus tubarius, Eustachian tube (ET), medial pterygoid plate and muscle, lateral nasal wall, and lateral pterygoid plate and muscle were sequentially performed to expose the fossa of Rosenmüller, petroclival region, parapharyngeal space (PPS), and jugular foramen, respectively.

Results Technical feasibility of endonasal nasopharyngectomy toward a posterolateral direction was validated in all 16 sides. Nasopharyngectomy was classified into four types as follows: (1) type 1: resection restricted to the posterior or superior nasopharynx; (2) type 2: resection includes the torus tubarius which is suitable for lesions extended into the petroclival region; (3) type 3: resection includes the distal cartilaginous ET, medial pterygoid plate, and muscle, often required for lesions extending laterally into the PPS; And (4) type 4: resection includes the lateral nasal wall, pterygoid plates and muscles, and all the cartilaginous ET. This extensive resection is required for lesions involving the carotid artery or extending to the jugular foramen region.

Conclusion Selected lesions with posterolateral invasion into the PPS or jugular foramen is amenable to a resection via expanded endonasal approach. Classification of nasopharyngectomy based on tumor depth of posterolateral invasion helps to plan a surgical approach.
The Anesthetic Modality but Not the Mode of Delivery Seem to Modulate the Methylation Status of Cyclooxygenase-2 Promoter of the Newborns
Authors: Oğuz Suna Şerife , Kutman Gözde Hayriye Kanmaz , Oğuz Kemal
Published: September 2021

Objective Cesarean section (CS) rates are high. Epidemiological data supports increased risk of inflammatory conditions in the offspring born by CS. Epigenetic alterations occurring during the perinatal period may account for this risk. Cyclooxygenase-2 (COX2) has strong implications for inflammatory diseases. The methylation of COX2 of newborn infants was compared with respect to their mode of delivery.

Study Design Ninety healthy term infants born by vaginal delivery (VD), planned cesarean section (PCS), or emergency CS (ECS) were recruited (30 infants in each group). For obstetric anesthesia, local (LA), regional (RA), or general (GA) anesthesia were used. Carefully selected exclusion criteria were implemented to eliminate any confounders with potential epigenetic effects. Umbilical artery blood samples were collected. Demographic and clinical characteristics, folate and CRP levels, and mean methylation levels of the COX2 gene promoter were determined.

Results Except the birth weight and maternal age parameters, VD, PCS, and ECS were similar. The methylation percentage of COX2 was higher in ECS (16.9 ± 5.1) than VD (14.5 ± 4.1) and PCS (14.8 ± 2.9), albeit p was 0.064. Because of the dual anesthetic modality populations (RA and GA) in PCS and ECS and the recent literature on anesthetics and epigenetics, the anesthetic modality groups were also analyzed. The methylation percentage of COX2 was significantly different between LA, RA, and GA groups (14.5 ± 4.1, 13.9 ± 2.8, and 17.0 ± 4.6, respectively, p = 0.012).

Conclusion When the mode of delivery is the question of debate, the anesthetic modality should be remembered as an important epigenetic modulator.

Key Points
Unilateral Multicanalicular Vestibular Lithiasis of Right Horizontal and Posterior Semicircular Canals: An Unusual Case
Authors: Vats Ajay Kumar
Published: September 2021

Vestibular lithiasis (canalolithiasis as well as cupulolithiasis) commonly exists in monocanalicular forms involving one of the three semicircular canals, frequent posterior, less frequent horizontal, and very rarely anterior. It is treated with canal clearing maneuvers intended to reposition the otoconia from the semicircular canal (where they have inappropriately entered) through the utricular exit in the nonampullary arm of the semicircular canal to the utricle (where they normally remain as a part of utricular gelatinous matrix). The cases of multicanalicular vestibular lithiasis with the involvement of more than one semicircular canal require meticulous identification of the involved canals and multiple different canal-clearing maneuvers for effective treatment. A 70-year-old male patient with no significant history of previous medical or otologic illnesses or head trauma presented with a 1-day history of vertigo with positional aggravation. A one-time performed diagnostic supine head roll test elicited three different patterns of positional nystagmus, each with an accurate localizing and lateralizing value. Diagnosis of unilateral multicanalicular vestibular lithiasis of right horizontal and posterior semicircular canals was entertained based on the pattern of the elicited positional nystagmi on the supine roll test. The upbeating torsional nystagmus that localizes the involvement to the posterior semicircular canal was paradoxically elicited by supine head roll test and not by the Dix–Hallpike test. As horizontal semicircular canalolithiasis causes severe symptoms, its treatment preceded that of concurrent posterior semicircular canalolithiasis. The patient was successfully treated with multiple sessions of canalith repositioning maneuvers (CRMs) spread over 24 hours. It is important to perform both positional tests, namely Dix–Hallpike maneuver, and supine head roll test, in cases suspected to have multicanalicular vestibular lithiasis. The positionings may need to be repeated several times to unveil multiple nystagmi, each with different localizing and lateralizing values. Identifying treatment priorities with CRM for the individual semicircular canals is crucial, and the canal that is liable to cause severe symptoms needs early clearance of the otoconial debris. If a CRM fails to clear a semicircular canal, an alternative maneuver may need to be executed. Clinicians involved in the care of cases with multicanalicular vestibular lithiasis should be well versed with all possible backup maneuvers for clearing each of the three semicircular canals.
A Young Patient with Horizontal Semicircular Cupulolithiasis with Immediate Response to the Therapeutic Head-Shaking Maneuver (HSM)
Authors: Vats Ajay Kumar
Published: September 2021

The apogeotropic variant of horizontal semicircular canal benign paroxysmal positional vertigo is attributed to either short anterior ampullary arm canalolithiasis or to the cupulolithiasis with the otoconial debris adhering to the cupula on utricular (Cup-U) or canal side (Cup-C), rendering it heavy and gravity sensitive. The treatment options for horizontal semicircular cupulolithiasis are not very well defined. A 25-year-old female patient with 8 days history of vertigo on rolling to either of the lateral recumbent position presented in the first week of November 2019. The supine roll test (SRT) on yawing head maximally to the right as well as to the left elicited an apogeotropic horizontal positional nystagmus lasting more than 1 minute, which was stronger on the right side and indicated a diagnosis of left horizontal semicircular cupulolithiasis. Two short-term follow-ups at 1 and 24 hours after head-shaking maneuver (HSM), with verifying SRT, were undertaken. During either of the two follow-ups, neither the previously elicited horizontal positional nystagmus was observed, nor did the patient have vertigo on rolling to lateral recumbent positions. She was telephonically questioned weekly regarding the recurrence of rotational vertigo for the next 4 weeks, and it was confirmed that she remained symptom free till then. The therapeutic HSM, owing to the inertial forces generated, can detach the otoconial debris from the cupula that renders it heavy and gravity sensitive. Successful offloading of cupula by HSM brings immediate cure in the Cup-U variant of the horizontal semicircular cupulolithiasis.
Electronic spectra, topological states, and impurity effects in graphene nanoribbons
Authors: Pogorelov Yu. G. , Kochan D. , Loktev V. M.
Published: September 2021

We consider the finite ribbons of graphene with two principal orientations, zigzag and armchair, of their edges to study in detail impurity effects on their edge states. An alternative to the known description of quasiparticle states in terms of transversal standing waves is proposed in the recurrence relations for their spectra vs discrete numbers of atomic chains in the ribbon, permitting to simplify the Green function approach to the disorder effects in these systems. The derived analysis shows the microscopic mechanisms of perturbation by different types of impurities on low energy states and clarifies how the stability of topological states in zigzag systems to disorder is related to the discrete amplitudes of these states across the ribbon. An opposite possibility for Mott localization under local impurity perturbations is found for armchair type nanoribbons but at special values of their width.
A practical guide to modeling low-current quasi-stationary gas discharges: Eigenvalue, stationary, and time-dependent solvers
Authors: Benilov M. S. , Almeida P. G. C. , Ferreira N. G. C. , Almeida R. M. S. , Naidis G. V.
Published: September 2021

The work is concerned with the modeling of low-current quasi-stationary discharges, including the Townsend and corona discharges. The aim is to develop an integrated approach suitable for the computation of the whole range of existence of a quasi-stationary discharge from its inception to a non-stationary transition to another discharge form, such as a transition from the Townsend discharge to a normal glow discharge or the corona-to-streamer transition. This task includes three steps: (i) modeling of the ignition of a self-sustaining discharge, (ii) modeling of the quasi-stationary evolution of the discharge with increasing current, and (iii) the determination of the current range where the quasi-stationary discharge becomes unstable and the non-stationary transition to another discharge form begins. Each of these three steps is considered in some detail with a number of examples, referring mostly to discharges in high-pressure air.
Particle emission with identification from an atmospheric pressure plasma liquid interface
Authors: Kovach Yao E. , Wang Zhehui , Foster John E.
Published: September 2021

A conspicuous emission phenomenon of luminous particles from the liquid anode surface of an atmospheric pressure DC glow discharge is reported. The emission has been shown to occur when the plasma forms a pattern on the surface of the liquid electrolyte. The spatial-temporal evolutions of the trajectories of emitted particles were studied using a high-speed imaging system. Particles were sampled in flight using a witness plate for analysis. Critical particle characteristics were examined using electron microscope technologies. The morphology of the resulting splats and compositions suggest that they are molten droplets with a great deal of structure, including evidence of nanoprecipitation. A theoretical model was employed to estimate the particle size from the measured splats, which provides a radius range within a hundred micrometers. This experiment leads to the postulation of a mechanism in which particle emission at the plasma liquid interface is likely driven by the Taylor cone effect.
Trap states induced hopping transport and persistent photoconductivity in WSe2/MoS2 nanocomposite thin films
Authors: Kaur Manjot , Singh Kulwinder , Kumar Akshay
Published: September 2021

In this work, temperature-dependent electrical transport and photoconductivity studies of WSe2/MoS2 nanocomposite thin films have been analyzed. An n-type semiconductor film of ≈150 nm with a carrier concentration of ≈1023cm−3 is prepared by a thermal evaporation technique. Temperature-dependent (150–350 K) conductivity results present more than one type of carrier transport mechanisms. Trap states from chalcogenide vacancies in WSe2/MoS2 play an important role in the formation of localized states. The electrical conductivity of the composite conforms to Mott’s variable range-hopping model due to these localized states in the temperature range of 150–250 K. Nearest-neighbor hopping and a thermally activated conduction mechanism are responsible for electrical transport in the higher temperature range. The role of defect/trap states and random local potential fluctuations in persistent photoconductivity has also been studied. Also, the effect of vacuum and air atmosphere shows that acceptor states resulting from incorporation of oxygen in sulfur vacancies results in more photocurrent in air than vacuum. The results deepen the understanding of the conduction mechanism in such multifunctional transition-metal dichalcogenide based nanocomposites.
Probing size variations of molecular aggregates inside chlorosomes using single-object spectroscopy
Authors: Kunsel T. , Günther L. M. , Köhler J. , Jansen T. L. C. , Knoester J.
Published: September 2021

We theoretically investigate the possibility to use single-object spectroscopy to probe size variations of the bacteriochlorophyll aggregates inside chlorosomes. Chlorosomes are the light-harvesting organelles of green sulfur and non-sulfur bacteria. They are known to be the most efficient light-harvesting systems in nature. Key to this efficiency is the organization of bacteriochlorophyll molecules in large self-assembled aggregates that define the secondary structure inside the chlorosomes. Many studies have been reported to elucidate the morphology of these aggregates and the molecular packing inside them. It is widely believed that tubular aggregates play an important role. Because the size (radius and length) of these aggregates affects the optical and excitation energy transport properties, it is of interest to be able to probe these quantities inside chlorosomes. We show that a combination of single-chlorosome linear polarization resolved spectroscopy and single-chlorosome circular dichroism spectroscopy may be used to access the typical size of the tubular aggregates within a chlorosome and, thus, probe possible variations between individual chlorosomes that may result, for instance, from different stages in growth or different growth conditions.
Growth of ordered two-dimensional cobalt phthalocyanine films on a one-dimensional substrate
Authors: Kubicki Milan , Lindner-Franz Susi , Dähne Mario , Franz Martin
Published: September 2021

The growth of Co phthalocyanine (CoPc) films on the one-dimensional Si(111)(4 × 1)-In surface is studied using scanning tunneling microscopy (STM). At low CoPc coverages, the molecules are highly mobile on the surface. Only when the coverage approaches the saturation coverage, the molecules stabilize each other and a highly ordered two-dimensional CoPc monolayer forms. Based on the STM images, a structure model for this film could be developed, with the molecules selectively adsorbing on the In chains with a (4 × 4) periodicity.
Wigner localization in two and three dimensions: An ab initio approach
Authors: Escobar Azor Miguel , Alves Estefania , Evangelisti Stefano , Berger J. Arjan
Published: September 2021

In this work, we investigate the Wigner localization of two interacting electrons at very low density in two and three dimensions using the exact diagonalization of the many-body Hamiltonian. We use our recently developed method based on Clifford periodic boundary conditions with a renormalized distance in the Coulomb potential. To accurately represent the electronic wave function, we use a regular distribution in space of Gaussian-type orbitals and we take advantage of the translational symmetry of the system to efficiently calculate the electronic wave function. We are thus able to accurately describe the wave function up to very low density. We validate our approach by comparing our results to a semi-classical model that becomes exact in the low-density limit. With our approach, we are able to observe the Wigner localization without ambiguity.
Suspended AlGaAs waveguide for integrated nonlinear photonics
Authors: Cong Hui , Yang Bo , Wei Wenqi , Wang Jianhuan , Feng Qi , Wang Zihao , Wang Ting , Guo Xuhan , Zhang Jianjun
Published: September 2021

AlxGa1-xAs compound is one of the promising platforms to realize high performance nonlinear optical devices, which provide ultra-high third order nonlinearity and negligible two-photon absorption in the range of telecom wavelength. To achieve highly efficient optical confinement, the conventional AlGaAs waveguide cladding layer is achieved by using SiO2 via the wafer bonding process or AlGaAs with higher Al concentration, which requires a complex fabrication process. In this work, we demonstrate a suspended Al0.5Ga0.5As waveguide structure directly grown on the GaAs substrate by using the molecular beam epitaxy system. Both self-phase modulation and four-wave-mixing experiments are performed. By solving the nonlinear Schrödinger equations and the degenerated parametric amplification process, the n2 value is calculated to be 1.6 × 10−17 m2/W, and the nonlinear parameter is determined to be 155 W−1 m−1. As the AlGaAs thin film can be directly grown on the Si based substrate, this suspended waveguide platform could potentially be developed on a large scale silicon wafer for integrated nonlinear photonic devices.
Silver nanoparticles (AgNPs) internalization and passage through the Lactuca sativa (Asteraceae) outer cell wall
Authors: de Paiva Pinheiro Sergimar Kennedy , Rangel Miguel Thaiz Batista Azevedo , Chaves Marlos de Medeiros , Barros Francisco Claudio de Freitas , Farias Camila Pessoa , de Moura Thiago Alves , Ferreira Odair Pastor , Paschoal Alexandre Rocha , Souza Filho Antonio Gomes , de Castro Miguel Emilio
Published: September 2021

Silver nanoparticle (AgNPs) toxicity is related to nanoparticle interaction with the cell wall of microorganisms and plants. This interaction alters cell wall conformation with increased reactive oxygen species (ROS) in the cell. With the increase of ROS in the cell, the dissolution of zero silver (Ag0) to ionic silver (Ag+) occurs, which is a strong oxidant agent to the cellular wall. AgNP interaction was evaluated by transmission electron microscopy (TEM) on Lactuca sativa roots, and the mechanism of passage through the outer cell wall (OCW) was also proposed. The results suggest that Ag+ binds to the hydroxyls (OH) present in the cellulose structure, thus causing the breakdown of the hydrogen bonds. Changes in cell wall structure facilitate the passage of AgNPs, reaching the plasma membrane. According to the literature, silver nanoparticles with an average diameter of 15 nm are transported across the membrane into the cells by caveolines. This work describes the interaction between AgNPs and the cell wall and proposes a transport model through the outer cell wall.
Melatonin improves the maturation and developmental ability of bovine oocytes by up-regulating GJA4 to enhance gap junction intercellular communication
Authors: Hao Tong , Xu Xi , Hao Haisheng , Du Weihua , Pang Yunwei , Zhao Shanjiang , Zou Huiying , Yang Sha , Zhu Huabin , Yang Yuze , Zhao Xueming
Published: September 2021

Melatonin (MT) increases oocyte maturation by reducing reactive oxygen species level and enhancing oocyte antioxidant capacity. However, the mechanisms via which MT works are still poorly understood. In the present study, the effects of MT on the maturation rate and development ability of bovine oocytes were investigated. Then, the transcriptome of oocytes treated by MT was sequenced. Finally, the expression of gap junction protein alpha 4 (GJA4) protein and cAMP level were detected in bovine oocytes, and isoprenaline (enhancer of gap junctional intercellular communication (GJIC)) and heptanol (inhibitor of GJIC) were used to investigate the effect of MT on GJIC activity in bovine oocytes. Our results showed that MT significantly improved the maturation, developmental ability and mRNA expression of GJA4 of bovine oocytes. Meanwhile, MT significantly increased GJA4 protein level and cAMP level in bovine oocytes. In contrast to heptanol, both isoproterenol and MT significantly increased GJIC activity, nuclear maturation and the development ability of bovine oocytes. However, MT significantly restored the nuclear maturation and developmental ability of oocytes treated by heptanol. In conclusion, our results showed that MT improves the maturation and developmental ability of bovine oocytes by enhancing GJIC activity via up-regulating GJA4 protein expression in IVM progress.
Computational prediction of the effect of amino acid changes on the binding affinity between SARS-CoV-2 spike RBD and human ACE2
Authors: Chen Chen , Boorla Veda Sheersh , Banerjee Deepro , Chowdhury Ratul , Cavener Victoria S. , Nissly Ruth H. , Gontu Abhinay , Boyle Nina R. , Vandegrift Kurt , Nair Meera Surendran , Kuchipudi Suresh V. , Maranas Costas D.
Published: September 2021

Significance

SARS-CoV-2 infection proceeds through the binding of viral surface spike protein to the human ACE2 protein. The global spread of the infection has led to the emergence of fitter and more transmissible variants with increased adaptation both in human and nonhuman hosts. Molecular simulations of the binding event between the spike and ACE2 proteins offer a route to assess potential increase or decrease in infectivity by measuring the change in binding strength. We trained a neural network model that accurately maps simulated binding energies to experimental changes in binding strength upon amino acid changes in the spike protein. This computational workflow can be used to a priori assess currently circulating and prospectively future viral variants for their affinity for hACE2.
DNA origami patterning of synthetic T cell receptors reveals spatial control of the sensitivity and kinetics of signal activation
Authors: Dong Rui , Aksel Tural , Chan Waipan , Germain Ronald N. , Vale Ronald D. , Douglas Shawn M.
Published: September 2021

Significance

It has been proposed that the spatial arrangement of ligands plays a key role in regulating downstream intracellular signals. Because of methodological limitations in precise ligand patterning, however, the relationship between spatial configuration of clusters and signaling dynamics remains poorly understood. By developing a DNA-based molecular “pegboard” for ligand patterning, we demonstrated that the nanometer arrangement of ligands plays significant roles in modulating signal transduction in T cells. Ligand clustering not only affects the triggering sensitivity but also determines the temporal dynamics of the intracellular signaling response. Our approach is highly translatable for studying various signaling pathways, and our results provide insights into biomolecular engineering for therapeutic uses.
Integrating CDA with ideological rhetorical criticism in the investigation of Abe Cabinet’s discursive construction in “Indo-Pacific Strategy”
Authors: Tian Weiqi , Chai Hongmei , Lu Lin
Published: September 2021

In recent years, the Indo-Pacific strategy and the Quad concept have been introduced and advocated by various countries. Since the second term of Japanese Prime Minister Shinzo Abe, the “Indo-Pacific Strategy” has been widely promoted. Assisted by corpus linguistics, this paper aims to explore the implicit ideology by providing insight into the context model from CDA perspective, and to decode the discursive construction by combining “ideographs” and “policy triggers” as Ideological Rhetorical Criticism instructed. The study shows these political texts are rich in forms of rhetorical strategies of “routinization”, “hegemony”, “uniformization” and “naturalization” used to construct a discursive system to distinguish “them” from “us”, so that to realize political aims.
/ka-/ negative prefix of Choswateng Tibetan of Khams (Shangri-La, Yunnan)
Authors: Suzuki Hiroyuki , Lhamo Lozong
Published: September 2021

Choswateng Tibetan, spoken in the south-eastern corner of the Khams region, has three negative prefixes: /ȵi-/,
/ma-/, and /ka-/. The first two are derived from two morphemes which are ubiquitous across Tibetic languages, whereas the third is
a newly generated negative prefix found in Choswateng Tibetan as well as its surrounding dialects belonging to the rGyalthang
subgroup of Khams and its neighbours. This article describes the morphological feature and use of the prefix /ka-/ in Choswateng
Tibetan. Morphologically, the prefix /ka-/ can co-occur with most verbs except for the copulative verb /ˊreʔ/. Pragmatically, the
prefix /ka-/ occurs and is restricted in the following ways: (1) expresses ‘definitely not’ for statements regarding the self, and
‘possibly not, judging from the speaker’s knowledge’ for statements regarding others; (2) co-occurs with egophoric and sensory
evidentials; (3) is not used for a negation of accomplished aspect; and (4) does not deprive the function of the other two
negative prefixes. These two analyzes are mutually related; it is suggested that the reason why /ka-/ cannot co-occur with the
copulative verb /ˊreʔ/ is triggered by a contradiction of implied evidentials: /ka-/ is related to egophoric and sensory, whereas
/ˊreʔ/ is statemental. Following the description of its use, we discuss the origin of /ka-/, claiming a possible
grammaticalization from an interrogative word gar (‘where’ in Literary Tibetan and common throughout the
rGyalthang area) in a rhetorical question to a prefix. Referring to several morphological features of /ka-/, we consider its
grammaticalization as ongoing, but most advanced in Choswateng Tibetan.