bluuebunny/crossref_metadata_2025 huggingface dataset:
Charge carrier dynamics in two-dimensional hybrid perovskites: Dion–Jacobson vs. Ruddlesden–Popper phases
Authors: Ghosh Dibyajyoti , Acharya Debdipto , Pedesseau Laurent , Katan Claudine , Even Jacky , Tretiak Sergei , Neukirch Amanda J.
Published: August 2020

Compared to the Ruddlesden–Popper-phase, we find that the Dion–Jacobson-phase 2D iodide perovskites have a slower rate of non-radiative carrier recombination.
Cultural Awareness of Students in Communication Sciences and Disorders: A Mixed-Methods Study
Authors: Domsch Celeste , Stiritz Lori , Huff Jay
Published: August 2020

Purpose

This study used a mixed-methods design to assess changes in students' cultural awareness during and following a short-term study abroad.

Method

Thirty-six undergraduate and graduate students participated in a 2-week study abroad to England during the summers of 2016 and 2017. Quantitative data were collected using standardized self-report measures administered prior to departure and after returning to the United States and were analyzed using paired-samples
t
tests. Qualitative data were collected in the form of daily journal reflections during the trip and interviews after returning to the United States and analyzed using phenomenological methods.

Results

No statistically significant changes were evident on any standardized self-report measures once corrections for multiple
t
tests were applied. In addition, a ceiling effect was found on one measure. On the qualitative measures, themes from student transcripts included increased global awareness and a sense of personal growth.

Conclusions

Measuring cultural awareness poses many challenges. One is that social desirability bias may influence responses. A second is that current measures of cultural competence may exhibit ceiling or floor effects. Analysis of qualitative data may be more useful in examining effects of participation in a short-term study abroad, which appears to result in decreased ethnocentrism and increased global awareness in communication sciences and disorders students. Future work may wish to consider the long-term effects of participation in a study abroad for emerging professionals in the field.
Monitoring of the evolution of H2O vapor in the stratosphere of Jupiter over an 18-yr period with the Odin space telescope
Authors:   The Odin Team, Benmahi B. , Cavalié T. , Dobrijevic M. , Biver N. , Bermudez-Diaz K. , Sandqvist Aa. , Lellouch E. , Moreno R. , Fouchet T. , Hue V. , Hartogh P. , Billebaud F. , Lecacheux A. , Hjalmarson Å. , Frisk U. , Olberg M.
Published: August 2020

Context. The comet Shoemaker-Levy 9 impacted Jupiter in July 1994, leaving its stratosphere with several new species, with water vapor (H2O) among them.

Aims. With the aid of a photochemical model, H2O can be used as a dynamical tracer in the Jovian stratosphere. In this paper, we aim to constrain the vertical eddy diffusion (Kzz) at levels where H2O is present.

Methods. We monitored the H2O disk-averaged emission at 556.936 GHz with the space telescope between 2002 and 2019, covering nearly two decades. We analyzed the data with a combination of 1D photochemical and radiative transfer models to constrain the vertical eddy diffusion in the stratosphere of Jupiter. Results. Odin observations show us that the emission of H2O has an almost linear decrease of about 40% between 2002 and 2019. We can only reproduce our time series if we increase the magnitude of Kzz in the pressure range where H2O diffuses downward from 2002 to 2019, that is, from ~0.2 mbar to ~5 mbar. However, this modified Kzz is incompatible with hydrocarbon observations. We find that even if an allowance is made for the initially large abundances of H2O and CO at the impact latitudes, the photochemical conversion of H2O to CO2 is not sufficient to explain the progressive decline of the H2O line emission, which is suggestive of additional loss mechanisms.

Conclusions. The Kzz we derived from the Odin observations of H2O can only be viewed as an upper limit in the ~0.2 mbar to ~5 mbar pressure range. The incompatibility between the interpretations made from H2O and hydrocarbon observations probably results from 1D modeling limitations. Meridional variability of H2O, most probably at auroral latitudes, would need to be assessed and compared with that of hydrocarbons to quantify the role of auroral chemistry in the temporal evolution of the H2O abundance since the SL9 impacts. Modeling the temporal evolution of SL9 species with a 2D model would naturally be the next step in this area of study.
The influence of welding parameters on macrostructure and mechanical properties of Sc-modified AA2519-T62 FSW joints
Authors: Kosturek Robert , Śnieżek Lucjan , Torzewski Janusz , Wachowski Marcin
Published: August 2020

In this investigation, a 5 mm thick extrusion of AA2519-T62 alloy has been welded using friction stir welding method. The various sets of process parameters have been involved within the range of 400–1200 rpm tool rotation speed and 100–800 mm/min welding speed. Selected joints have been subjected to the macrostructure analysis, microhardness measurements, tensile and low cycle fatigue testing (atε = 0.3%), and fractography analysis. It has been stated that imperfection-free macrostructure is obtained for welds produced with lowest welding speed: 100 mm/min and tool rotation speed within the range of 400–800 rpm. The highest joint efficiency (85%) has been obtained for the sample characterized by the presence of voids in the upper part of the stir zone. Considering macrostructure analysis and established mechanical properties of the joints, it may be concluded that the best set of welding parameters for AA2519-T62 is within the range of 600–800 rpm tool rotation speed with welding speed of 100 mm/min for used MX Triflute tool.
Study of cutting force and tool wear during turning of aluminium with WC, PCD and HFCVD coated MCD tools
Authors: Pattnaik Sisira Kanta , Behera Minaketan , Padhi Sachidananda , Dash Pusparaj , Sarangi Saroj Kumar
Published: August 2020

Enormous developmental work has been made in synthesis of metastable diamond by hot filament chemical vapor deposition (HFCVD) method. In this paper, micro-crystalline diamond (MCD) was deposited on WC–6 wt.% Co cutting tool inserts by HFCVD technique. The MCD coated tool was characterized by the scanning electron microscope (SEM), X-ray diffraction (XRD) and micro Raman spectroscopy (μ-RS). A comparison was made among the MCD tool, uncoated tungsten carbide (WC) tool and polycrystalline diamond (PCD) tool during the dry turning of rolled aluminum. The various major tests were conducted such as surface roughness, cutting force and tool wear, which were taken into consideration to establish a proper comparison among the advanced cutting tools. Surface roughness was measured during machining by Talysurf. The tool wear was studied by SEM after machining. The cutting forces were measured by Kistler 3D-dynamometer during the machining process. The test results indicate that, the CVD coated MCD tool and PCD tool produced almost similar results. But, the price of PCD tools are five times costlier than MCD tools. So, MCD tool would be a better alternative for machining of aluminium.
Verbesserung der Arzneimitteltherapiesicherheit durch ein
klinikinternes Meldesystem – Analyse der Meldungen über 15 Jahre
einer Kinderklinik
Authors: Toni Irmgard , Neubert Antje , Rascher Wolfgang
Published: August 2020

Hintergrund Die Patientensicherheit ist eine große
Herausforderung und hat hohe Priorität in der stationären
Behandlung von Patienten. Neben chirurgischen Eingriffen gilt v. a. die
Arzneimitteltherapie als kritisch. Dabei ist der Medikationsprozess bei
Neugeborenen und Kindern besonders diffizil und problematisch.

Methode In einer retrospektiven Analyse wurden klinikinterne
Spontanberichte zu Arzneimitteltherapiebezogenen Problemen (ATBP) einer Kinder-
und Jugendklinik analysiert, die in den Jahren 2000–2014 gemeldet
wurden.

Ergebnisse 229 Spontanmeldungen zu ATBP wurden für die Analyse
berücksichtigt. 72,5% dieser erfolgten aufgrund eines
Medikationsfehlers. Knapp die Hälfte der ATBP ereignete sich
während der Abgabe von Arzneimitteln (44,5%), gefolgt von
Problemen bei der Anwendung (38,0%) und der Verordnung (11,4%).
Medikationsfehler waren zu 61,4% Abgabefehler (v. a.
Verwechslung von Patienten, fehlerhafte Dosis), sonstige Ereignisse wurden
nahezu vollständig der Arzneimittelanwendung zugeordnet (v. a.
Paravasate). 40,6% der ATBP waren mit einem klinisch relevanten
Patientenschaden verbunden und traten primär während der
Arzneimittelanwendung auf.

Schlussfolgerung Die Ergebnisse zeigen, dass die Arzneimitteltherapie in
der Pädiatrie ein komplexer und riskanter Prozess ist. Das System der
klinikinternen Spontanmeldungen führte zu regelmäßigen
Schulungen und zur Sensibilisierung der Mitarbeiter für kritische
Situationen. Zudem fördert es eine Kultur der Sicherheit, Fehler offen
zu berichten. Spontanmeldungen sind geeignet die Arzneimitteltherapie in der
Pädiatrie sicherer zu machen.
A case of primary adenocarcinoma of the seminal vesicle treated by total laparoscopic pelvic exenteration
Authors: Tochigi Kosuke , Matsukawa Yoshihisa , Ishida Shohei , Funahashi Yasuhito , Fujita Takashi , Kato Masashi , Gotoh Momokazu
Published: August 2020

An adenocarcinoma of the seminal vesicle is a rare malignancy with a poor prognosis. Its symptoms are non-specific, rendering diagnosis difficult. We present the case of a 74-year-old male with haematospermia. Magnetic resonance imaging revealed a bulky tumour of the seminal vesicle infiltrating the prostate gland, bladder and rectum. A transrectal ultrasound-guided biopsy revealed an adenocarcinoma. Computed tomography revealed multiple lung metastases. The serum CA-125 level was high. Androgen deprivation therapy and chemotherapy (docetaxel) were prescribed. After 12 courses of docetaxel, the primary tumour and the lung metastases decreased in size and the serum CA-125 level returned to normal. The patient underwent total laparoscopic pelvic exenteration with placement of a neobladder. Histological examination revealed a mucinous adenocarcinoma with negative surgical margins. The patient did not receive adjuvant chemotherapy or radiation. He shows no evidence of recurrence 19 months after surgery.
Caffeine Supplementation or Carbohydrate Mouth Rinse Improves Performance
Authors: Pereira Paulo Eduardo Assis , Azevedo Paulo , Azevedo Katia , Azevedo Warleyson , Machado Marco
Published: August 2020

Training volume is one of the critical variables required to promote resistance training benefits (e. g., hypertrophy, muscular strength). Thus, strategies to improve training volume are required. We tested the hypothesis that there is an increase in performance and reduction in the rate of perceived exertion in strength training with caffeine supplementation, carbohydrate mouth rinse, and a synergistic effect of caffeine supplementation plus carbohydrate mouth rinse. We recruited 29 physically active women: 24±4 years, 60.0±7.9 kg, 161.0±6.0 cm. This study was a double-blind, randomized, placebo-controlled, and crossover one. The subjects performed all sessions of strength training under different conditions: caffeine (6.5 mg·kg−1 body mass); carbohydrate (6 g of maltodextrin rinsed for 10 s); caffeine plus carbohydrate; or placebo. We applied the ANOVA for repeated measures through the null-hypothesis statistical test, and the Bayes factors analyses approach. The subjects showed significant improvement in the total repetitions (P<0.01; BF10 ~99%) for both lower and upper limb exercises in all conditions compared to placebo without difference among interventions. The rate of perceived exertion (P>0.05) did not differ among interventions. However, BF10 analyses showed a higher probability of lower RPE for CAF intervention. We conclude that either caffeine supplementation or carbohydrate mouth rinse can improve performance in resistance training. There is no additional effect of caffeine plus carbohydrate.
Changes in Lung Diffusing Capacity of Elite Artistic Swimmers During
Training
Authors: García Iker , Drobnic Franchek , Pons Victoria , Viscor Ginés
Published: August 2020

Artistic swimmers (AS) are exposed to repeated apnoeas in the aquatic environment
during high intensity exercise provoking specific physiological responses to
training, apnoea, and immersion. This study aimed to evaluate the changes in
lung diffusing capacity in AS pre-, mid- and post-training in a combined session
of apnoeic swimming, figures and choreography. Eleven elite female AS from the
Spanish national team were the study’s participants. The single-breath
method was used to measure lung diffusing capacity for carbon monoxide
(DLCO) and one-way repeated measures ANOVA was utilized to
evaluate the statistical analysis. Basal values of DLCO were higher
than normal for their age and height
(33.6±4.9 mL·min−1·mmHg−1;
139±19%) and there were a significant interaction between
DLCO and AS training (ŋ2
p=0.547). After the apnoeic swimming (mid-training) there was
an increase in DLCO from basal to
36.7±7.3 mL·min−1·mmHg−1
(p=0.021), and after the figures and choreography (post-training) there
was a decrease compared to mid-training
(32.3±4.6 mL·min−1·mmHg−1,
p=0.013). Lung diffusing capacity changes occur during AS training,
including a large increase after apnoeic swimming. There were no differences in
lung diffusing capacity from pre- to post-training, although large
inter-individual variability was observed.
Carbonylative Suzuki–Miyaura Coupling Reactions of Aryl Iodides with Readily Available Polymer-Immobilized Palladium Nanoparticles
Authors: Yasukawa Tomohiro , Kobayashi Shu , Zhu Zhiyuan , Yamashita Yasuhiro
Published: August 2020

Polysilane/alumina-supported palladium nanoparticle catalyzed carbonylative Suzuki–Miyaura coupling reactions under ligand-free conditions have been developed to synthesize diaryl ketones. High yields and selectivities were achieved even with low catalyst loading under atmospheric pressure of CO gas. A variety of aryl iodides and arylboronic acids could be utilized to afford the diaryl ketones in excellent yields. Moreover, the ligand-free immobilized palladium nanoparticles could be recovered by simple filtration and the catalytic activity could be maintained for several runs.
Electrochemical Synthesis of Vinyl Sulfones by Sulfonylation of Styrenes with a Catalytic Amount of Potassium Iodide
Authors: Gao Hui , Li Pin-Hua , Wang Pei-Long , Jiang Zhi-Sheng , Li Chao , Tian Zhi-Ao
Published: August 2020

An electrochemical sulfonylation reaction of styrenes was developed in which sodium arylsulfinates were used as sulfonylating reagents, a catalytic amount of KI was used as a redox mediator, and Bu4NBF4 was used as the electrolyte. In addition to various styrenes, sodium arylsulfinates with either electron-donating or electron-withdrawing groups were tolerated.
Mythri 1.0—Progress of an Indian Surgical Robot
Authors: V. Vikas , Voggu Aravind Reddy , Arumalla Kirit , Doshi Ronak , Ramkumar Aravind , Mahadevan Anita , Rao Madhav
Published: August 2020

Neurosurgical procedures are performed using operating microscopes. The technology of most microscopes has not changed much over the past 60 years. The National Institute of Mental Health and Neurosciences and International Institute of Information Technology based at Bengaluru have embarked on joint collaboration for developing robot for neurosurgical applications. As a working prototype, robotic microscope Mythri 1.0 has been developed. An overview of the development process, working, and features of the device is presented in the article.
Nasal High Frequency Oscillatory Ventilation for Respiratory Failure due to Respiratory Syncytial Virus Bronchiolitis: Case Report
Authors: Liberatore Pio , Maffei Gianfranco
Published: August 2020

The authors describe a case of acute respiratory failure due to severe bronchiolitis. During high-flow nasal cannula ventilation, the blood's high levels of hypercapnia had taken them to plan the sedation and the orotracheal intubation. However, before attempting intubation, a nasal high frequency oscillatory ventilation cycle was performed and it led to a marked improvement in the blood gas, avoiding in this way the invasive ventilation.
Imaging Postoperative Abdominal Hernias: A Review with a Clinical Perspective
Authors: Chatterjee Argha , Ramanan Rochita V. , Mukhopadhyay Sumit
Published: August 2020

Postoperative internal hernia is a challenging but critical diagnosis in postoperative patients presenting with acute abdomen. Postoperative internal hernias are increasingly being recognized after Roux-en-Y gastric bypass (RYGB) and bariatric surgeries. These internal hernias have a high risk of closed-loop obstruction and bowel ischemia; therefore, prompt recognition is necessary. Computed tomography (CT) is the imaging modality of choice in cases of postoperative acute abdomen. Understanding the types of postoperative internal hernia and their common imaging features on CT is crucial for the abdominal radiologist. Postoperative external hernias are usually a result of defect or weakness of the abdominal wall created because of the surgery. CT helps in the detection, delineation, diagnosis of complications, and surgical planning of an external hernia. In this article, the anatomy, pathophysiology, and CT features of common postoperative hernias are discussed. Afterreading this review, the readers should be able to (1) enumerate the common postoperative internal and external abdominal hernias, (2) explain the pathophysiology and surgical anatomy of Roux-en-Y gastric bypass-related hernia, (3) identify the common imaging features of postoperative hernia, and (4) diagnose the complications of postoperative hernias.
Growing of integrable turbulence
Authors: Agafontsev D. S. , Zakharov V. E.
Published: August 2020

We study numerically the integrable turbulence in the framework of the focusing one-dimensional nonlinear Schrodinger equation using a new method — the “growing of turbulence”. We add to the equation a weak controlled pumping term and start adiabatic evolution of turbulence from statistically homogeneous Gaussian noise. After reaching a certain level of average intensity, we switch off the pumping and realize that the “grown up” turbulence is statistically stationary. We measure its Fourier spectrum, the probability density function (PDF) of intensity and the autocorrelation of intensity. Additionally, we show that, being adiabatic, our method produces stationary states of the integrable turbulence for the intermediate moments of pumping as well. Presently, we consider only the turbulence of relatively small level of nonlinearity; however, even this “moderate” turbulence is characterized by enhanced generation of rogue waves.
Magnetotransport properties of nanogranular composites with low-field positive magnetoresistance
Authors: Kulyk M. M. , Ryabchenko S. M. , Bodnaruk A. V.
Published: August 2020

A low-temperature feature is detected in nanogranular magnetic films with perpendicular anisotropy that have a low-field positive magnetoresistance: positive magnetoresistance is observed during the initial magnetization of the demagnetized sample, but is absent when the magnetic field is removed and/or during subsequent magnetizations. This effect is studied using a Cox(Al2On)1−x film with x = 0.60, consisting of Co metal nanogranules in an Al2On insulating matrix with n close to 3. It is found that together with perpendicular anisotropy, the film has local in-plane anisotropy with randomly oriented easy axes, which prevents the reorientation of the granules’ magnetic moment projections in the film plane below a certain blocking temperature. The restoration of the local short-range order in the orientation of the magnetic moments of the demagnetized film’s neighboring granules, which is optimal for conductivity and is destroyed by the introduction of a magnetic field, is prevented at temperatures below the blocking temperature and is not restored during subsequent cycles of introducing/removing the magnetic field without heating to temperatures above the blocking temperature.
Aharonov–Casher effect and electric field control of magnetization dynamics
Authors: Krivoruchko V. N.
Published: August 2020

A spin wave (SW) propagating in an external electric field acquires an extra phase, the so-called Aharonov– Casher phase. To linear order, that is equivalent the SW frequency shift linear in both the applied electric field and the wave vector of SW’s and can be described by adding effective Dzyaloshinskii–Moriya-like interaction between spins. This effect is a promising way to control and manipulate magnetization precession dynamics by electric field and opens up a new way of SWs steering in magnonic devices. The goal of the report is to emphasize a fundamental physical difference in the nature of external electric field effect through the Aharonov–Casher phase shift and of a voltage control of magnetic anisotropy (VCMA). In the context of an experimental performance, we deal with almost identical experimental conditions. Yet, from the quantum physics point of view, we deal with different effects and this is important to understand the experimental results. In the case of the Aharonov–Casher phase shift it is a global nonlocal (topological) effect and in the case of VCMA it is the influence on a system’s local (Landau) magnetic parameters (e.g., magnetic anisotropy).
Wannier-Stark ladder spectrum of Bloch oscillations of magneto-dipole spin waves in graded 1D magnonic crystals
Authors: Tartakovskaya E. V. , Laurenson A. S. , Kruglyak V. V.
Published: August 2020

We have used the method of Wannier functions to calculate the frequencies and profiles of spin waves localized in one-dimensional magnonic crystals due to a gradient in the bias magnetic field. This localization of spin waves is analogous to the phenomenon of Bloch oscillations of quantum-mechanical electrons in crystals in a uniform electric field. As a convenient yet realistic model, we consider backward volume magnetostatic spin waves in a film of yttrium-iron garnet in a bias magnetic field comprising spatially uniform, cosine and gradient contributions. The spin-wave spectrum is shown to have the characteristic form of a Wannier–Stark ladder. The analytical results are verified using those obtained using numerical micromagnetic simulations. The physics of spin-wave Bloch oscillations combines the topics of magnonic crystals and graded magnonic index — the two cornerstones of modern magnonics.
Topological characteristics of building blocks in the domain wall of an antiferromagnet with the Dzyaloshinskii–Moriya interaction
Authors: Gorobets O. Yu. , Gorobets Yu. I.
Published: August 2020

Topological charges are calculated for a number of exact three-dimensional analytical solutions to the Landau–Lifshitz equation, which describe the distributions of the vector fields for the vectors of antiferromagnetism and antiferromagnet magnetization. It is shown that in the case of samples with dimensions that are comparable to the characteristic scales of topological objects of the antiferromagnetism and magnetization vector fields, there are modified characteristics that depend not only on the topological properties of these objects, but also on the geometry of the sample. These modified characteristics in samples with finite dimensions may assume non-integer values.
On the theory of systems with substitutional non-Hermitian disorder
Authors: Skrypnyk Y. V. , Loktev V. M.
Published: August 2020

A novel family of disordered systems is proposed. This family belongs to the class of systems containing random substitutional non-Hermitian impurities. We limit our consideration to a rather simple case when the presence of substitutional point defects results in the model Hamiltonian featuring a diagonal disorder. In contrast to known models of non-Hermitian impurities, the nonzero density of states for each isolated from the host impurity is restricted to a continuous band of finite width. A method to construct corresponding impurity Hamiltonians is provided.
Modeling dust in a tokamak
Authors: Larter Raima
Published: August 2020

Investigators develop a simulation method to study dust transport in tokamak fusion reactors, revealing unexpected features that could affect future reactor plans.
Time-dependent modeling of dust outburst into tokamak divertor plasma
Authors: Smirnov R. D. , Krasheninnikov S. I.
Published: August 2020

The first self-consistent simulation studies of the impact of transient injection of tungsten dust on ITER-like edge plasma are presented. The simulations are performed using DUSTT and UEDGE codes coupled in a fully time-dependent manner. The evolution of the divertor and upstream plasma conditions, following the injection of tungsten dust of various quantities and sizes at the outer strike point, is investigated. The estimates of the core plasma impurity fraction and the core impurity screening factor associated with the dust injection are also obtained. The simulations show that the bursts of even modest amounts of tungsten dust injected into the divertor plasmas can result in large perturbations of the divertor power load and unacceptable levels of the core plasma contamination with tungsten impurities.
Laser-induced densification of fused silica using spatially overlapping sub-30 fs pulses
Authors: McMillen Ben , Uteza Olivier , Clady Raphaël , Sanner Nicolas , Sentis Marc , Nabiei Farhang , Cheng Ya , Bellouard Yves
Published: August 2020

Over the past several years, non-ablative femtosecond laser exposure with spatially overlapping (i.e., spatially cumulative) pulses has emerged as a key process in three-dimensional writing of patterns in bulk of dielectric substrates. When temporally non-cumulative and combined with post-processing steps, this process defines a novel manufacturing technique in fused silica, finding uses in a broad number of applications, including—but not limited to—micromechanics, integrated optics, microelectronics, microfluidics, information storage, and combinations of these fields for novel integrated sensing applications. For fused silica, evidence has shown that there is a pulse-length duration threshold around 200 fs, marking the boundary between two radically different characteristic material modification regimes, each leading to a specific application. Pulse widths below 200 fs lead to localized densification, enabling the direct-write of optical waveguides, while pulse widths above this value produce self-organized nanostructures causing a localized volume expansion and enhanced etching susceptibility to various chemicals. Here, we focus our attention on the regime below 200 fs, using low repetition rates and temporally non-cumulative pulses. In particular, we use very short pulses, i.e., in the range of 30 fs—a regime as yet unexplored from the viewpoint of spatially cumulative modifications. Our goal is to understand how structural modifications obtained by overlapping pulses evolve with varying pulse overlap, and how shorter pulse duration may correlate with higher material densification. This knowledge is particularly important for the next generation of photonics devices, where increasing the level of laser-induced densification is a key factor for high-density photonic integration.
Electric field control of molecular magnetic state by two-dimensional ferroelectric heterostructure engineering
Authors: Zhu Ziye , Zhang Baiyu , Chen Xiaofang , Qian Xiaofeng , Qi Jingshan
Published: August 2020

Two-dimensional multiferroics have attracted tremendous attention due to their intriguing physics and promising applications. However, it has been a major challenge to discover and design two-dimensional multiferroic materials with large electric polarization and strong magnetoelectric coupling. In this work, we propose a strategy to design a two-dimensional van der Waals heterostructure with strong magnetoelectric coupling by stacking a transition metal phthalocyanine (TMPc) molecule with ferroelectric monolayer In2Se3. By first-principles electronic structure calculations, we predict that the magnetic states of the TMPc molecule can be controlled by electrically switching the polarization direction of In2Se3 using an external electric field. This strong magnetoelectric coupling effect originates from the interfacial charge transfer and orbital splitting, resulting in the different magnetic states of TMPc/In2Se3 heterostructures in two opposite ferroelectric phases. Based on the TMPc/In2Se3 heterostructure, a high-density magnetic memory device is proposed for pure electric writing and magnetic reading. Our predictions may open avenues for finding and designing multiferroic heterostructures by using two-dimensional ferroelectric materials and zero-dimensional magnetic molecules with a strong proximity effect.
Trion-to-exciton upconversion dynamics in monolayer WSe2
Authors: Lan Wenze , Wang Jing , Xin Ming , Huang Yuan , Gu Changzhi , Liu Baoli
Published: August 2020

We investigate the trion-to-exciton upconversion dynamics in a large-scale mechanically exfoliated tungsten diselenide (WSe2) monolayer covered by poly(methyl methacrylate) using two-color ultrafast pump-probe spectroscopy. With resonantly pumping the trion and probing the exciton transitions, we find a fast trion-to-exciton upconversion process with the upconversion time about ∼2 ps. Combined with the temperature-dependent transient reflection and helicity-resolved Raman measurements, we further demonstrate that the upconversion is indeed a phonon-mediated process in our sample.
Large-range frequency tuning of a narrow-linewidth quantum emitter
Authors: Zhai Liang , Löbl Matthias C. , Jahn Jan-Philipp , Huo Yongheng , Treutlein Philipp , Schmidt Oliver G. , Rastelli Armando , Warburton Richard J.
Published: August 2020

A hybrid system of a semiconductor quantum dot single photon source and a rubidium quantum memory represents a promising architecture for future photonic quantum repeaters. One of the key challenges lies in matching the emission frequency of quantum dots with the transition frequency of rubidium atoms while preserving the relevant emission properties. Here, we demonstrate the bidirectional frequency tuning of the emission from a narrow-linewidth (close-to-transform-limited) quantum dot. The frequency tuning is based on a piezoelectric strain-amplification device, which can apply significant stress to thick bulk samples. The induced strain shifts the emission frequency of the quantum dot over a total range of 1.15 THz, about three orders of magnitude larger than its linewidth. Throughout the whole tuning process, both the spectral properties of the quantum dot and its single-photon emission characteristics are preserved. Our results show that external stress can be used as a promising tool for reversible frequency tuning of high-quality quantum dots and pave the wave toward the realization of a quantum dot–rubidium atom interface for quantum networking.
A Perspective on interfacial engineering of lithium metal anodes and beyond
Authors: Yan Qizhang , Whang Grace , Wei Ziyang , Ko Shu-Ting , Sautet Philippe , Tolbert Sarah H. , Dunn Bruce S. , Luo Jian
Published: August 2020

This Perspective reviews interfacial engineering of lithium metal anodes. Critical issues and open scientific questions related to coatings on the lithium metal anode are discussed. Essential features for ideal coatings, especially those that can potentially enable lithium plating underneath the coating, are highlighted. While most existing approaches use kinetic control to regulate the coating thickness, here we offer a Perspective on thermodynamically controlled interfacial engineering, focusing on spontaneously formed 2D interfacial phases (also known as “complexions”). This approach has been applied to other battery systems but has yet to be realized for lithium metal anodes.
Tuning the optical nonlinearity of graphene
Authors: Li Ying , Li Hui , Wu Shiwei , Liu Wei-Tao
Published: August 2020

Tuning of nonlinear optical responses is the essence to many photonics and optoelectronics applications. Due to the low-dimensionality and dispersion of massless Dirac Fermions, the nonlinear optical susceptibilities of graphene can be readily controlled via electrical gating. Based on the quantum interference between multi-photon transition pathways, the tuning mechanism of graphene nonlinearity is intrinsically different from most other systems. The phenomenon enables investigations into some nonlinear optical processes from fundamental regards. It also exhibits appealing features contrasting conventional materials, which can be desirable for novel device applications.
Femtosecond time-resolved nonlinear optical spectroscopy of charge transfer at the buried GaP/Si(001) interface
Authors: Mette G. , Zimmermann J. E. , Lerch A. , Brixius K. , Güdde J. , Beyer A. , Dürr M. , Volz K. , Stolz W. , Höfer U.
Published: August 2020

The ultrafast charge-carrier dynamics at the buried heterointerface of gallium phosphide on silicon(001) are investigated by means of time-resolved optical second-harmonic generation. Photon energy dependent measurements reveal the existence of electronic interface states in the bandgap of both materials. Charge carriers excited via these interface states are efficiently injected within a few hundred femtoseconds from the GaP/Si interface into the Si substrate, resulting in the build-up of an electric field perpendicular to the interface on a picosecond time scale.
Electron beam-induced electrostatic charging causes spectral changes of an insulating electrochromic material
Authors: Rhinow Daniel , Hampp Norbert
Published: August 2020

Electrostatic charging of electrically insulating samples upon electron irradiation plays a large role in the analysis and processing of materials in biosciences and the semiconductor industry. We have analyzed spectral changes of purple membranes (PMs) containing bacteriorhodopsin, an electrochromic biological material, upon irradiation with electrons at an acceleration voltage of 30 kV. We observed a bathochromic shift in the UV/VIS spectrum of PM films, due to internal electric fields generated by charges injected into the films. The experiments demonstrate that spectroscopic changes, accompanying electron beam-induced charge injection into electrochromic materials, enable quantitative analysis of electrostatic charging of insulators upon electron irradiation by optical spectroscopy.
The cochlear outer hair cell speed paradox
Authors: Rabbitt Richard D.
Published: August 2020

Significance

Mammalian hearing requires outer hair cells for amplification and tuning in the cochlea. The amplification process works at frequencies at least 10 times higher than might be expected based on electrical properties of the cells. The present report demonstrates how protein-dependent membrane piezoelectricity underlies high-frequency function, and why power output is maximum at frequencies much higher than would be predicted based on traditional experimental measurements. The interplay between electrical charge displacement and mechanical strain in the membrane motor is key. The same biophysical principles identify the origins of infrared laser-induced capacitive currents reported previously in hair cells, HEK cells, and neurons.
Nonholomorphic Ramanujan-type congruences for Hurwitz class numbers
Authors: Beckwith Olivia , Raum Martin , Richter Olav K.
Published: August 2020

Significance

Hurwitz class numbers were introduced over 100 y ago, and they impact different areas of mathematics. In particular, their generating function is a so-called mock modular form. Despite their importance, essentially nothing has been known about the divisibility properties of Hurwitz class numbers on arithmetic progressions. Our work provides results on such divisibility properties, which differ drastically from known divisibility results for coefficients of other mock modular forms.
Novel parasite invasion leads to rapid demographic compensation and recovery in an experimental population of guppies
Authors: Rogowski Emma L.B. , Van Alst Andy D. , Travis Joseph , Reznick David N. , Coulson Tim , Bassar Ronald D.
Published: August 2020

Significance

Does increased mortality from novel predators or parasites always lead to decreased prey or host population sizes? Theory says no, but we have too few examples of such compensatory effects to answer this question conclusively. We address this gap using long-term data from populations recently invaded by a nematode parasite. We combine analyses of the subsequent changes in population dynamics with comparable data from an uninfected population and laboratory assays of the effect of the parasite on fitness components. Our results show that the negative effect of the novel parasite was short-lived. The host population quickly recovered, even while experiencing high levels of parasite prevalence (72%). Host recovery was a consequence of increased survival and a density-dependent increase in recruitment.
POPOVICH, encoding a C2H2 zinc-finger transcription factor, plays a central role in the development of a key innovation, floral nectar spurs, inAquilegia
Authors: Ballerini Evangeline S. , Min Ya , Edwards Molly B. , Kramer Elena M. , Hodges Scott A.
Published: August 2020

Significance

Throughout evolutionary history, organisms have evolved features that allow them to interact with their environment in novel ways. When such features lead to increased rates of speciation in a lineage, we call them key innovations. Understanding the genetic and developmental changes involved in the origin of key innovations is of particular interest. Here we identify a gene,POPOVICH, that is crucial to the development of a key innovation, floral nectar spurs, in the columbine genusAquilegia. While the function ofPOPOVICHorthologs in other plant taxa suggests an ancestral function of the lineage in leaf development, inAquilegia,POPOVICHalso functions to promote cell division in petals, a key cellular step in the development of nectar spurs in the genus.
Age-related loss of neural stem cell O-GlcNAc promotes a glial fate switch through STAT3 activation
Authors: White Charles W. , Fan Xuelai , Maynard Jason C. , Wheatley Elizabeth G. , Bieri Gregor , Couthouis Julien , Burlingame Alma L. , Villeda Saul A.
Published: August 2020

Significance

Depletion of the neural stem cell (NSC) pool is a major driver of age-related regenerative decline in the hippocampus. While increased quiescence is a major contributor to this decline, NSCs can also undergo terminal differentiation into astrocytes, thus restricting the stem cell pool. The mechanisms underlying this fate switch and their relation to age-related regenerative decline have not yet been fully elucidated. In this study, we report an age-related decline in NSC O-GlcNAcylation, coincident with reduced neurogenesis and increased gliogenesis. We identify loss of O-GlcNAcylation at STAT3 T717 in the hippocampus with age, and demonstrate that O-GlcNAcylation of this site is a critical determinant of NSC fate. Our work expands our understanding of how posttranslational modifications influence the aging brain.
Control of fear extinction by hypothalamic melanin-concentrating hormone–expressing neurons
Authors: Concetti Cristina , Bracey Edward F. , Peleg-Raibstein Daria , Burdakov Denis
Published: August 2020

Significance

Excessive fear is a hallmark of disabling anxiety disorders that affect millions of people worldwide. Its suppression is thus of great interest, but the necessary brain components remain incompletely identified. We found that inappropriate, learning-resistant fear results from disruption of brain components not previously implicated in this disorder: hypothalamic melanin-concentrating hormone–expressing neurons (MNs). We show that the brain converts fear-inducing events into MN signals. These brief signals are necessary for healthy long-term flexibility of fear behavior. Without them, a fearful experience leads to abnormal treatment-resistant, relapsing fear reminiscent of posttraumatic stress disorder. These findings identify natural brain signals that suppress excessive fear behavior.
Heraclitus armeniacus
Authors: Jeck Udo Reinhold
Published: August 2020

It is a great loss to philosophy that Heraclitus’s writing was
lost in antiquity, for the surviving fragments rarely contain more than one
sentence. Often, they are succinct but concise statements that contain little
text. So, when one succeeds in augmenting important fragments with a few words
or illuminating their context, there is progress in Heraclitus research.
Sometimes, however, this requires recourse to lineages outside the Greek-Latin
tradition.

An example of this is provided by fragment 123, which has played
an important role since its discovery in the Orationes of
Themistius: in the 20th century, Martin Heidegger used it several times for his
idiosyncratic interpretation of Heraclitus and the philosophy of the
Pre-Socratics. However, he did not consider that an Armenian variant of this
fragment had become available at the beginning of the 19th century. This
Armenian variant derives from a treatise of Philo of Alexandria which has only
been transmitted in Armenian and offers more text than the Greek version. As
Diels-Kranz did not include this Armenian source in their edition of The
Fragments of the Pre-Socratics, this Armenian variant fell into
oblivion and was not known to Heidegger either.

Now this article, after introductory remarks on the transmission
of Heraclitus’s sayings in Themistius and Philo’s Heraclitea,
focuses on the history of the Armenian version of fragment 123 and its primary
interpretations. It concludes with a reconstruction of the remarks which
Ferdinand Lassalle dedicated to this fragment in both its Greek and Armenian
versions in 1858.
Freundschaft und Liebe bei Platon und Plotin
Authors: Schramm Michael
Published: August 2020

Abstrakt

Der Artikel fragt nach der Rezeption von Platons Freundschafts- und Liebesbegriff bei Plotin. Zunächst wird gezeigt, dass Platons Liebestheorie im Symposion und im Phaidros gleichermaßen auf den Aufstieg zum Ideenhimmel und die Selbstvervollkommnung des Liebenden abzielt, wobei der Phaidros mit der Freundschaft als schwächerer, durch Reziprozität gekennzeichneter Form der Liebe die soziale Dimension des Aufstiegs und der Vervollkommnung thematisiert. Dann wird nachgezeichnet, inwiefern Plotins Liebes- und Freundschaftsbegriff Theorieelemente aus Platons Symposion und Phaidros fortentwickelt. Nach Plotin ist die Liebe das Movens des Aufstiegs zum Einen und die Freundschaft das Movens des dazu komplementären Abstiegs zur Vielheit. Es wird schließlich gezeigt, dass Platon wie Plotin ausschließlich an der philosophischen Freundschaft und Liebe interessiert sind und diese zentral für ihr Konzept von Erziehung und Selbsterziehung sind.
Die proklische Diotima
Authors: Schultz Jana
Published: August 2020

Diotima, the priestess of Plato’s Symposium, is an important reference for Proclus’ thinking about the role of women in philosophical and religious practices. This character does not just offer Proclus an example for women’s ability to attain the same level of virtue than men, but she is also a model for the joint work of philosophical and religious practices. Thereby she stands for practices which are orientated on the human condition and therefore depend on intermediary entities as demons, and for practices which transcend both the human condition and the intermediary entities. Most interesting in Proclus’ presentation of Diotima as a priestess and a philosopher is that he does not present her to fulfill these roles by masculinizing her soul through a sole focus on the intelligible entities – as for example Porphyry advises his wife Marcella – but by using the female element in her soul, i.e. the circuit of the Different, as an intermediate through which she can get in touch with the demons and – through them – also with higher entities. The ideal which Diotima incorporates is therefore not becoming masculine (despite having a female body) but harmonizing the male and female elements within the soul.
Die Theorie des Schönen des Johannes Scottus Eriugena
Authors: Koch Philipp
Published: August 2020

Abstrakt

Der vorliegende Artikel befasst sich mit der Theorie des Schönen und der Schönheit im Denken des Johannes Scottus Eriugena, basierend auf seinem Hauptwerk Periphyseon, den ‚Aulae sidereae‘ (Carmen 25), einem Gedicht Eriugenas, und dem Kommentar zur Schrift ‚Über die himmlische Rangfolge‘ des Pseudo-Dionysius Areopagita. Dazu werden zunächst die metaphysischen Grundlagen für eine Theorie des Schönen im System des Eriugena, wie er sie im s.o. erarbeitet, kurz und prägnant vorgestellt: Für Eriugena ist das Seiende eine Erscheinung und Manifestation Gottes, des unsagbaren Prinzips, des Einen. Danach wird aufgezeigt, wie Eriugena das Schöne als Konkretwerdung des Einen denkt, wobei zuerst die Schönheit der Natur besprochen wird, um dann einen Blick auf den Sonderfall der menschengemachten Kunst zu werfen. Das Ergebnis der Untersuchung ist, dass Eriugena die Kunst als eine reflexive Haltung des Menschen zur Welt und ihrem Ursprung versteht.
Francesco Piccolomini on honor
Authors: Guldentops Guy
Published: August 2020

‘Honor’ is one of the key notions in Renaissance ethics. The present paper analyzes the honor code which Francesco Piccolomini (1520–1604) articulates in his Vniuersa Philosophia de Moribus. Drawing not only on Aristotle, Plato, and ancient Stoicism, but also on medieval and early-modern Christian authorities, he argues that ‘proper honor’ is situated in the inner of a virtuous person because “everybody is the artificer of their own merits of honor.” Despite the aristocratic and patriarchal aspects of his ethics, he propounds an interiorizing and non-militarist interpretation of honor, which runs parallel with Montaigne’s concept of vray honneur and even anticipates to some extent Kant’s Ehrliebe.
Listening and comprehension in interpreting
Authors: Díaz-Galaz Stephanie
Published: August 2020

The study of skilled listening comprehension shows that listening is a complex, dynamic, and interactive process that
enables listeners to understand a message and respond adequately to the requirements of communicative interaction. Individual factors, such
as language proficiency, working memory capacity, and previous knowledge, interact in the listening process and performance. Moreover,
skilled listeners deploy controlled strategies directed at making the best use of their abilities to achieve a specific communicative goal.
However, our understanding of individual variables, such as language proficiency, topic-specific knowledge, and the strategies that
interpreters use when listening for interpreting, remain mostly unexplored. This article presents listening comprehension as a goal-directed
activity and articulates recent research on individual factors involved in listening comprehension with current conceptions of comprehension
for interpreting. This review identifies relevant gaps in our understanding about the comprehension process in interpreting.
Coping with the stress caused by the COVID-19 pandemic: future research agenda based on emotional intelligence ((Afrontando el estrés causado por la pandemia COVID-19: futura agenda de investigación desde la inteligencia emocional))
Authors: Extremera Natalio
Published: August 2020

Emotional intelligence provides a unified theoretical framework for studying the role of emotional skills in the processes of stress and well-being, which is extraordinarily applicable in this crisis caused by COVID-19. Thus, below we shall provide a non-exhaustive analysis of the potential consequences of this pandemic, suggesting several future avenues of research to examine intrapersonal and interpersonal psychosocial processes based on emotional intelligence.
Inequality viewed through the mirror of COVID-19 (La desigualdad ante el espejo del COVID-19)
Authors: Rodríguez-Bailón Rosa
Published: August 2020

The health crisis caused by the spread of COVID-19 will deepen the economic inequality already found in most countries. Among other effects, it will increase the health, educational and labour gap among citizens. Taking into account the psychosocial effects of economic inequality can be useful when proposing actions aimed at reducing its negative effects.