bluuebunny/crossref_metadata_2025 huggingface dataset:
Enhanced catalytic peroxymonosulfate activation over carbon shells encapsulating cobalt ferrite via radical and nonradical routes
Authors: Zhu Kaixin , Liang Binglian , Jin Changzi , Klencsár Zoltán , Zhao Chunxiao , Huang Yanqiang , Hu Ruisheng , Wang Junhu
Published: November 2020

Well-defined carbon shells encapsulating CoFe2O4 were facilely fabricated for superior peroxymonosulfate activation performances by virtue of radical and nonradical mechanisms.
Nanocrystals of platinum-group metals as peroxidase mimics forin vitrodiagnostics
Authors: Wei Zhiyuan , Xi Zheng , Vlasov Sergey , Ayala Jasmin , Xia Xiaohu
Published: November 2020

The use of carefully engineered platinum-group metal nanocrystals as peroxidase mimics opens a new avenue to development of sensitivein vitrodiagnostic technologies.
Spacer group-controlled luminescence and response of C3-symmetric triphenylamine derivatives towards force stimuli
Authors: Han Yanning , Zhang Tong , Chen Xinyu , Chen Qiao , Xue Pengchong
Published: November 2020

Spacer groups have the ability to regulate the responses of two C3-symmetric triphenylamine derivatives. Double bonds induced larger spectral shifts compared to that of single bonds.
Tilting in coronene layers on Au(111)
Authors: Kabat Nathaniel W. , Monazami Ehsan , Reinke Petra
Published: November 2020

Control of molecule adsorption and ordering on metal surfaces is of critical importance for the design and fabrication of molecule-based functional materials.
Theoretical insights into the effect of size and substitution patterns of azobenzene derivatives on the DNA G-quadruplex
Authors: Gholamjani Moghaddam Kiana , Giudetti Goran , Sipma Wouter , Faraji Shirin
Published: November 2020

The effect of size and substitution patterns of azobenzene derivatives on the spectroscopic properties and rigidity of the smallest photoswitchable G-quadruplex.
A quantum-based molecular dynamics study of the ICM-102/HNO3 host–guest reaction at high temperatures
Authors: Xiao Yiwen , Chen Lang , Geng Deshen , Yang Kun , Lu Jianying , Wu Junying
Published: November 2020

The quantum-based MD method is used to investigate the reaction mechanism of a host–guest explosive system for the first time.
New theoretical insights into the photoinduced carrier transfer dynamics in WS2/WSe2 van der Waals heterostructures
Authors: Zeng Huadong , Liu Xiangyue , Zhang Hong , Cheng Xinlu
Published: November 2020

Based on time-dependent ab initio nonadiabatic molecular dynamics, we studied the photoinduced carrier transfer dynamics in WS2/WSe2 heterostructure.
Anharmonic phonon frequency and ultralow lattice thermal conductivity in β-Cu2Se liquid-like thermoelectrics
Authors: Zhang Wenjie , Zheng Chong , Dong Yanbing , Yang Jia-Yue , Liu Linhua
Published: November 2020

The prototype phonon-liquid electron-crystal β-Cu2Se has been ranked among the best thermoelectric material with its ultralow lattice thermal conductivity (κL).
Time-of-flight measurements of the low-energy scattering of CH4 from Ir(111)
Authors: Al Taleb Amjad , Miranda Rodolfo , Farías Daniel
Published: November 2020

High-resolution angular and energy resolved measurements of low-energy methane scattering from an Ir(111) surface.
Crystal facet engineering induced robust and sinter-resistant Au/α-MnO2 catalyst for efficient oxidation of propane: indispensable role of oxygen vacancies and Auδ+ species
Authors: Jian Yanfei , Jiang Zeyu , He Chi , Tian Mingjiao , Song Weiyu , Gao Guanqun , Chai Shouning
Published: November 2020

Optimizing the interaction between metal active centers and supports by tuning crystal facets is an effective strategy to improve the activity and stability of catalysts.
In situ synchrotron radiation investigation of V2O5–Nb2O5 metastable compounds: transformational kinetics at high temperatures with a new structural solution for the orthorhombic V4Nb20O60 phase
Authors: Caggiu Laura , Iacomini Antonio , Pistidda Claudio , Farina Valeria , Senes Nina , Cao Hujun , Gavini Elisabetta , Mulas Gabriele , Garroni Sebastiano , Enzo Stefano
Published: November 2020

In situ synchrotron and conventional XRD patterns were solved for the phase developed at 700 °C with the Amm2 orthorhombic space group, lattice parameters a = 21.187 Å; b = 3.827 Å; c = 19.377 Å; β = 119.83° and chemical composition V4Nb20O60 (ρ = 4.09 g cm−3).
Emerging perovskite quantum dot solar cells: feasible approaches to boost performance
Authors: Chen Jingxuan , Jia Donglin , Johansson Erik M. J. , Hagfeldt Anders , Zhang Xiaoliang
Published: November 2020

This review comprehensively summarizes the advances of emerging perovskite quantum dot solar cells, and various strategies applied to improve the device performance of PQDSCs are discussed.
A Ganoderma atrum polysaccharide alleviated DSS-induced ulcerative colitis by protecting the apoptosis/autophagy-regulated physical barrier and the DC-related immune barrier
Authors: Zheng Bing , Ying Mengxi , Xie Jianhua , Chen Yi , Wang Yudan , Ding Xiaomeng , Hong Jiaqian , Liao Wang , Yu Qiang
Published: November 2020

DSS destroyed the intestinal mucosa, while a Ganoderma atrum polysaccharide repaired the intestinal epithelial physical barrier and the DC-related immune barrier.
Determination of stable isotope ratios using nuclear reaction analysis coupled with a particle–gamma coincidence method
Authors: Allegro Paula Rangel Pestana , Rizzutto Márcia de Almeida , Added Nemitala , Aguiar Vitor Ângelo Paulino de , Toufen Dennis Lozano , Macchione Eduardo Luiz Augusto , Medina Nilberto Heder , Ribas Roberto Vicençotto , Oliveira José Roberto Brandão de , Escudeiro Rafael , Alcántara-Núñez Juan Antonio , Curado Jessica Fleury , Scarduelli Valdir Brunetti , Zagatto Vinicius Antonio Bocaline , Rodrigues Cléber Lima , Tabacniks Manfredo Harri
Published: November 2020

This study presents an alternative method to determine isotope ratios using a medium energy accelerator and simultaneously measuring the charged particles and gamma-rays produced in a nuclear reaction.
Detection and separation of Fe(ii) and Fe(iii) in aqueous solution by laser-induced breakdown spectroscopy coupled with chelating resin enrichment and pH value adjustment
Authors: Zheng Peichao , Zhao Huaidong , Wang Jinmei , Liu Ranning , Ding Ning , Mao Xuefeng , Lai Chunhong
Published: November 2020

Ferrous iron (Fe(ii)) is essential to organisms, but ferric iron (Fe(iii)) is toxic.
Gated and non-gated silver detection using microwave-assisted laser induced breakdown spectroscopy
Authors: Wakil M. A. , Alwahabi Zeyad T.
Published: November 2020

The detection of silver using microwave-assisted laser induced breakdown spectroscopy (MW-LIBS) is demonstrated in solid and liquid samples at a 338.28 nm emission line.
DeepSIBA: chemical structure-based inference of biological alterations using deep learning
Authors: Fotis C. , Meimetis N. , Sardis A. , Alexopoulos L. G.
Published: November 2020

Predicting whether a chemical structure leads to a desired or adverse biological effect can have a significant impact for in silico drug discovery.
Recent advances in formic acid electro-oxidation: from the fundamental mechanism to electrocatalysts
Authors: Fang Zhongying , Chen Wei
Published: November 2020

This review summarizes the recent advances of studies on formic acid electro-oxidation, including the reaction mechanism and the electrocatalysts used.
Interpretable machine learning as a tool for scientific discovery in chemistry
Authors: Dybowski Richard
Published: November 2020

There has been an upsurge of interest in applying machine learning to chemistry, and impressive predictive accuracies have been achieved, but this has been done without providing any insight into what has been learnt from the training data.
An antibacterial composite film based on cellulose acetate/TiO2 nanoparticles
Authors: Gao Ying , Wang Xiu , Li Xiang , Dai Hongqi
Published: November 2020

The aims of this paper were: (1) prevent the aggregation of TiO2 nanoparticles and obtain a uniform suspension; (2) obtain homogeneous composite films through three simple steps; (3) evaluate the antibacterial properties of CA/TiO2 composite films against E. coli.
Chirality-driven molecular packing structure difference and potential application for 3D printing of a series of bola-type Ala–Phe dipeptides
Authors: Zheng Cheng , Lin Shuwei , Hu Chuanjiang , Li Yi , Li Baozong , Yang Yonggang
Published: November 2020

For bola-type dipeptides based on Ala–Phe building block, the chirality of Phe residue at C-terminal determined the handedness of self-assemblies and stacking chirality of carbonyl groups.
MOF-derived magnetic Co@porous carbon as a direction-controlled micromotor for drug delivery
Authors: Zhu Hongli , Huang Jing , Chen Huijun , Feng Xiaomiao
Published: November 2020

Porous carbon nanocomposites decorated with magnetic Co nanoparticles were obtained via the direct carbonization of ZIF-67 and acted as micromotors with appropriate speeds, controllable motion, and long lifetimes for drug delivery.
Ti3C2Tx nanosheet wrapped core–shell MnO2 nanorods @ hollow porous carbon as a multifunctional polysulfide mediator for improved Li–S batteries
Authors: Zhang Heng , Zhang Peigen , Pan Long , He Wei , Qi Qi , Bao Zhuoheng , Yang Li , Zhang Wei , Barsoum Michel W. , Sun ZhengMing
Published: November 2020

A 3D self-assembled, multifunctional MCT hierarchical structure was developed to alleviate the shuttle effect for high-performance Li–S batteries.
New insight into SPR modulating by two-dimensional correlation spectroscopy: the case for an Ag/ITO system
Authors: Han Bingbing , Jin Sila , Chu Qi , Jin Yang , Xue Xiangxin , Guo Shuang , Park Yeonju , Chen Lei , Jung Young Mee
Published: November 2020

The localized surface plasmon resonance (LSPR) of Ag/indium tin oxide (ITO)@polystyrene (PS) in the visible-NIR region was dependent on the tuning of the carrier density caused by adjusting the thickness of the ITO layer.
Solubility-governed architectural design of polyhydroxyurethane-graft-poly(ε-caprolactone) copolymers
Authors: Pronoitis Charalampos , Hakkarainen Minna , Odelius Karin
Published: November 2020

Polyhydroxyurethane-graft-poly(ε-caprolactone) copolymers were prepared in bulk by designing a polyhydroxyurethane system with polymer-in-monomer solubility.
Chemistry of 3-hydroxy-2-aryl acrylate: syntheses, mechanisms, and applications
Authors: Rahaman Mizzanoor , Ali M. Shahnawaz , Jahan Khorshada , Belayet Jawad Bin , Rahman A. F. M. Towheedur , Hossain M. Mahmun
Published: November 2020

3-Hydroxy-2-aryl acrylate is important scaffold which is widely used for the synthesis of pharmacologically active compounds. This review summarises the synthetic methods of the 3-hydroxy-2-aryl acrylate including mechanisms and applications.
Unraveling the effect of Al doping on CO adsorption at ZnO(101̄0)
Authors: Nguyen D. C. , Phung Thanh Khoa , Vo Dai-Viet N. , Le Tu Hai , Khieu Dinh Quang , Pham Thong Le Minh
Published: November 2020

Al doping enhances the adsorption of CO on ZnO(101̄0) by facilitating π-back donation from the surface to CO.
Possible dissolution mechanism of alkali lignin in lactic acid-choline chloride under mild conditions
Authors: Liu Zhuang , Hou Yi , Hu Songqing , Li Youming
Published: November 2020

In this study, several representative deep eutectic solvents (DESs) were designed to evaluate the solubility for alkali lignin (AL).
A pectin/chitosan/zinc oxide nanocomposite for adsorption/photocatalytic remediation of carbamazepine in water samples
Authors: Attallah Olivia A. , Rabee Mahmoud
Published: November 2020

The present study investigates a synergistic adsorption/photodegradation technique catalyzed by a pectin/chitosan/zinc oxide (Pec/CS/ZnO) nanocomposite for the removal of carbamazepine (CBZ) in aqueous solutions under direct sunlight.
Efficient, continuous N-Boc deprotection of amines using solid acid catalysts
Authors: Wu Jing , Zheng Chunming , Li Bryan , Hawkins Joel M. , Scott Susannah L.
Published: November 2020

Rapid, catalytic N-Boc deprotection of aromatic and aliphatic amines is achieved using readily-available porous inorganic solid acids in flow.
Accurate crystal structures and chemical properties from NoSpherA2
Authors: Kleemiss Florian , Dolomanov Oleg V. , Bodensteiner Michael , Peyerimhoff Norbert , Midgley Laura , Bourhis Luc J. , Genoni Alessandro , Malaspina Lorraine A. , Jayatilaka Dylan , Spencer John L. , White Fraser , Grundkötter-Stock Bernhard , Steinhauer Simon , Lentz Dieter , Puschmann Horst , Grabowsky Simon
Published: November 2020

NoSpherA2 brings quantum crystallography to routine structure determination and to the analysis of chemical properties for any class of materials.
Light-deformable dynamic surface fabricated by ink-jet printing
Authors: Liu Sunqian , Liao Xiaoling , de Haan Laurens T. , You Yuxin , Ye Huapeng , Zhou Guofu , Yuan Dong
Published: November 2020

Dynamic surfaces which can change their topography with external stimuli have wide application prospects.
Novel elastic instability of amorphous solids in finite spatial dimensions
Authors: Shimada Masanari , Mizuno Hideyuki , Ikeda Atsushi
Published: November 2020

We study a disordered spring network to describe the low-frequency vibrational spectrum of amorphous solids.
Negative resistance for colloids driven over two barriers in a microchannel
Authors: Zimmermann Urs , Löwen Hartmut , Kreuter Christian , Erbe Artur , Leiderer Paul , Smallenburg Frank
Published: November 2020

When colloidal particles flow through a microchannel, two sequential barriers can be easier to cross than one.
Correction: Effects of droplet size and surfactants on anchoring in liquid crystal nanodroplets
Authors: Sumer Zeynep , Striolo Alberto
Published: November 2020

Correction for ‘Effects of droplet size and surfactants on anchoring in liquid crystal nanodroplets’ by Zeynep Sumer et al., Soft Matter, 2019, 15, 3914–3922, DOI: 10.1039/C9SM00291J.
Structure and dielectric properties of double A-site doped bismuth sodium titanate relaxor ferroelectrics for high power energy storage applications
Authors: Zhang Hangfeng , Yang Bin , Fortes A. Dominic , Yan Haixue , Abrahams Isaac
Published: November 2020

The structural and dielectric properties of barium/strontium substituted Bi0.5Na0.5TiO3 were examined in compositions of general formula (Ba0.4Sr0.6TiO3)x(Bi0.5Na0.5TiO3)1−x.
Recent advances in cellulose-based piezoelectric and triboelectric nanogenerators for energy harvesting: a review
Authors: Song Yiheng , Shi Zhuqun , Hu Guo-Hua , Xiong Chuanxi , Isogai Akira , Yang Quanling
Published: November 2020

Ingenious cellulose-based materials were applied in smart piezoelectric and triboelectric nanogenerators for highly efficient energy harvesting.
Green nanogold activity in experimental breast carcinoma in vivo
Authors: Hendi Awatif A. , El-Nagar Doaa Mohamed , Awad Manal A. , Ortashi Khalid M. , Alnamlah Reema Abdullah , Merghani Nada M.
Published: November 2020

Background: Over the past few years, fabrication of nanoparticles (NPs) has been deployed widely in technologies and many concerns have emerged about the hazardous effect on human health after NPs exposure.

Objective: Green synthesis of gold NPs (AuNPs) and assessment of their activity in 7,12-dimethylbenz(a)anthracene (DMBA)-induced breast cancer mouse model.

Methods: Chloroauric acid (HAuCl4) was used in formation of AuNPs with the help of Curcuma longa as aqueous reducing extract and stabilizing agent at room temperature. Formed NPs were characterized with UV-Vis spectrometry, Fourier-transform infrared spectroscopy (FTIR), Zetasizer measurement, Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). Virgin female albino mice with DMBA-induced breast cancer were treated with formed AuNPs for 5 consecutive days and were dissected after 28 days of the beginning of treatment.

Results: UV-Vis spectrometry showed absorbance maximum peak at 530 nm for formed AuNPs, FTIR confirmed formation of plant extract layer around formed NPs; zetasizer measurement revealed 278.2 nm as an average size of produced NPs; SEM and TEM approved formation of monodisperse spherical AuNPs. Biochemical analysis of untreated breast cancer group revealed marked changes in liver and kidney functions manifested by raised activity levels of alanine transaminase (ALT), aspartate aminotransferase (AST), blood urea nitrogen (BUN) and creatinine. Whereas, the treated group with AuNPs post-breast cancer induction displayed reduction in the activities (of ALT, AST and creatinine), while the BUN activity level was raised. Histopathological examination showed heavy incidence of tumor foci in the breast and lymph nodes belonged to the untreated breast cancer group confirmed with intense response to Ki-67 antibodies. While the treated group with AuNPs post-breast cancer induction showed degenerated tumor foci in the breast and lymph nodes with weak response to Ki-67 antibodies.

Conclusion: AuNPs were successfully synthesized using HAuCl4 and C. longa extract confirmed their ability to control DMBA-induced breast cancer in virgin female Swiss albino mice.
Sustained Attention in Developmental Language Disorder and Its Relation to Working Memory and Language
Authors: Smolak Erin , McGregor Karla K. , Arbisi-Kelm Tim , Eden Nichole
Published: November 2020

Purpose

Based on evidence of deficits in domain-general cognitive abilities associated with developmental language disorder (DLD), the current study examined sustained attention performance in children with DLD compared to children with typical language development (TLD) and the interrelations between visual–spatial sustained attention, visual–spatial working memory, and language abilities across groups.

Method

Participants included 67 children at 7 years of age: 25 children with DLD (13 girls and 12 boys) and 42 children with TLD (23 girls and 19 boys). We assessed children's visual–spatial sustained attention, visual–spatial working memory, and language ability on a test of narrative language.

Result

Children with DLD scored significantly below their peers on a measure of visual–spatial sustained attention. Significant intercorrelations were observed between sustained attention, working memory, and language ability within the DLD group, but no correlations were observed between these measures in the TLD group.

Conclusion

Children with DLD have domain-general deficits in sustained attention, and correlational results have implications for whether and how language abilities are supported by domain-general cognition in both typical and disordered development.
Feature‐oriented channel estimation in reconfigurable intelligent surface‐assisted wireless communication systems
Authors: Lin Junliang , Wang Gongpu , Fan Rongfei , Zou Yulong , Tsiftsis Theodoros A. , Tellambura Chintha
Published: November 2020

In this6study, the channel estimation problem is investigated for a wireless communication system assisted by a reconfigurable intelligent surface (RIS). The RIS thus creates an assistant channel, which has the features of positivity and dominance. Owing to these features, the channel estimation problem is formulated as a constrained residual sum of squares minimisation problem, which differs radically from the traditional channel estimation issue. An efficient Lagrange multiplier and dual ascent‐based estimation scheme is then designed to obtain an iterative solution for the estimator. Moreover, the Cramér–Rao lower bounds are deduced as a performance benchmark. Simulation results show that the authors' designed scheme improves the estimation accuracy up to 33%, compared with the conventional least‐square method in the low signal‐to‐noise ratio regime.
Distance‐based congestion control mechanism for CoAP in IoT
Authors: Bansal Sharu , Kumar Dilip
Published: November 2020

Designing a scalable and efficient application layer protocols for the Internet of Things (IoT) environment is an ongoing problem. The constrained application protocol (CoAP) offering RESTful services for IoT devices implements a simple congestion control mechanism. This study proposes and analyses the distance‐based congestion control CoAP (DCC‐CoAP) for the current state of the network and accordingly calculate the future flow rate to handle congestion. The authors’ main idea is to use the combination of distance between nodes and round trip time (RTT) measurements which limits the losses of CoAP messages, which is an efficient way to predict the network congestion. The user‐defined options, i.e. retransmission counter and timestamp of sent and received CON and ACK messages are introduced for mapping CON to ACK and measure RTT. The comparative analysis of the DCC‐CoAP with other congestion control mechanism like default CoAP, CoCoA+ is also highlighted in this study. With low additional computations, future RTT can be measured for avoiding congestion, and retransmission timeout varies with distance to avoid transaction losses. An algorithm with varying data rate has been used in homogeneous and mixed traffic to calculate the parameters in terms of packet delivery ratios, delay and retransmission count.
Kernel difference maximisation‐based sparse representation for more accurate face recognition
Authors: Wu Lian , Xu Wenbo , Zhao Jianchuan , Cui Zhongwei , Zhao Yong
Published: November 2020

Most methods for sparse representation are designed to be used in the original space. However, their performance is not always satisfactory especially when training samples are limited. According to the previous studies, more information can be obtained from samples in the feature space than those in the original space. The authors propose a novel kernel difference maximisation‐based sparse representation method, and its remarkable performance in face recognition is demonstrated by the experiments. The proposed method converts all the samples into the feature space, and a test sample can be denoted as a representation with all the training samples’ linear combinations. Besides, a novel solution scheme for sparse representation is utilised to obtain the regularisation‐based sparse solution. Finally, the classification of the test sample can be easily judged according to the representation result. The representation results of test samples from different classes obtained by their method are very different, making the classification of test samples easier. Besides, the proposed method is simpler than the related methods and does not require dictionary learning.
Overall computing offloading strategy based on deep reinforcement learning in vehicle fog computing
Authors: Tan HaiZhong , Zhu Limin
Published: November 2020

In order to solve the problem of network congestion caused by a large number of data requests generated by intelligent vehicles in LTE‐V network, a brand‐new fog server with fog computing function is deployed on both the cellular base stations and vehicles, and an LTE‐V‐fog network is constructed to deal with delay‐sensitive service requests in the Internet of vehicles. The weighted total cost combines delay and energy consumption is taken as the optimisation goal. First a reinforcement learning algorithm Q ‐learning based on Markov decision process is proposed to solve the problem for minimising weighted total cost. Furthermore, this study specifically explains the setting method of three elements for reinforcement learning‐state, action and reward in the fog computing system. Then for reducing the scale of problems and improving efficiency, the authors set up a pre‐classification process before reinforcement learning to control the possible values of actions. However, considering that as the number of vehicles in system increases, Q ‐learning method based on recorded Q values may fall into a dimensional disaster. Therefore, the authors propose a deep reinforcement learning method, deep Q ‐learning network (DQN), which combines deep learning and Q ‐learning. Experimental results show that the proposed method has advantages.
Rotational spectroscopic study of S-methyl thioformate
Authors: Jabri A. , Tercero B. , Margulès L. , Motiyenko R. A. , Alekseev E. A. , Kleiner I. , Cernicharo J. , Guillemin J.-C.
Published: November 2020

Context. S-methyl thioformate CH3SC(O)H is a monosulfur derivative of methyl formate, a relatively abundant component of the interstellar medium (ISM). S-methyl thioformate being, thermodynamically, the most stable isomer, it can be reasonably proposed for detection in the ISM.

Aims. This work aims to experimentally study and theoretically analyze the ground and first torsional excited states for CH3SC(O)H in a large spectral range for astrophysical use.

Methods. S-methyl thioformate was synthesized as a result of a reaction of methyl mercaptan with acetic-formic anhydride. The millimeter-wave spectrum was then recorded for the first time from 150 to 660 GHz with the solid-state spectrometer located at Lille.

Results. A set of 3545 lines is determined and combined with 54 previously measured lines in the microwave region, belonging to ground state νt = 0 as well as 1391 transitions in the first excited state of torsion ν18 = 1. Some 164 lines were also assigned to ν18 = 2 for the A-species. A global fit was performed using the BELGI-Cs code taking into account the large splitting of A and E lines due to methyl internal rotation motion with a relatively low barrier, V3 = 127.4846(15) cm−1.

Conclusions. Using our spectroscopy work, a deep search of S-methyl thioformate was carried out in the IRAM 30 m and ALMA data of different high-mass star-forming regions (Orion KL and Sgr B2). We derived an upper limit to the CH3SC(O)H column density in these regions.
Searching for proto-planets with MUSE
Authors: Xie C. , Haffert S. Y. , de Boer J. , Kenworthy M. A. , Brinchmann J. , Girard J. , Snellen I. A. G. , Keller C. U.
Published: November 2020

Context. Protoplanetary disks contain structures such as gaps, rings, and spirals, which are thought to be produced by the interaction between the disk and embedded protoplanets. However, only a few planet candidates are found orbiting within protoplanetary disks, and most of them are being challenged as having been confused with disk features.

Aims. The VLT/MUSE discovery of PDS 70 c demonstrated a powerful way of searching for still-forming protoplanets by targeting accretion signatures with medium-resolution integral field spectroscopy. We aim to discover more proto-planetary candidates with MUSE, with a secondary aim of improving the high-resolution spectral differential imaging (HRSDI) technique by analyzing the instrumental residuals of MUSE.

Methods. We analyzed MUSE observations of five young stars with various apparent brightnesses and spectral types. We applied the HRSDI technique to perform high-contrast imaging. The detection limits were estimated using fake planet injections.

Results. With a 30 min integration time, MUSE can reach 5σ detection limits in apparent Hα line flux down to 10−14 and 10−15 erg s−1 cm−2 at 0.075′′ and 0.25′′, respectively. In addition to PDS 70 b and c, we did not detect any clear accretion signatures in PDS 70, J1850-3147, and V1094 Sco down to 0.1′′. MUSE avoids the small sample statistics problem by measuring the noise characteristics in the spatial direction at multiple wavelengths. We detected two asymmetric atomic jets in HD 163296 with a very high spatial resolution (down to 8 au) and medium spectral resolution (R ~ 2500).

Conclusions. The HRSDI technique when applied to MUSE data allows us to reach the photon noise limit at small separations (i.e., <0.5′′). With the combination of high-contrast imaging and medium spectral resolution, MUSE can achieve fainter detection limits in apparent line flux than SPHERE/ZIMPOL by a factor of ~5. MUSE has some instrumental issues that limit the contrast that appear in cases with strong point sources, which can be either a spatial point source due to high Strehl observations or a spectral point source due to a high line-to-continuum ratio. We modified the HRSDI technique to better handle the instrumental artifacts and improve the detection limits. To avoid the instrumental effects altogether, we suggest faint young stars with relatively low Hα line-to-continuum ratio to be the most suitable targets for MUSE to search for potential protoplanets.
Thermal-nonthermal energy partition in solar flares derived from X-ray, EUV, and bolometric observations
Authors: Warmuth A. , Mann G.
Published: November 2020

Context.In solar flares, energy is released impulsively and is partly converted into thermal energy of hot plasmas and kinetic energy of accelerated nonthermal particles. It is crucial to constrain the partition of these two energy components to understand energy release and transport as well as particle acceleration in solar flares. Despite numerous efforts, no consensus on quantifying this energy balance has yet been reached.

Aims.We aim to understand the reasons for the contradicting results on energy partition obtained by various recent studies. The overarching question we address is whether there is sufficient energy in nonthermal particles to account for the thermal flare component.

Methods.We considered five recent studies that address the thermal-nonthermal energy partition in solar flares. Their results are reviewed, and their methods are compared and discussed in detail.

Results.The main uncertainties in deriving the energy partition are identified as (a) the derivation of the differential emission measure distribution and (b) the role of the conductive energy loss for the thermal component, as well as (c) the determination of the low-energy cutoff for the injected electrons. The bolometric radiated energy, as a proxy for the total energy released in the flare, is a useful independent constraint on both thermal and nonthermal energetics. In most of the cases, the derived energetics are consistent with this constraint. There are indications that the thermal-nonthermal energy partition changes with flare strength: in weak flares, there appears to be a deficit of energetic electrons, while the injected nonthermal energy is sufficient to account for the thermal component in strong flares. This behavior is identified as the main cause of the dissimilar results in the studies we considered. The changing partition has two important consequences: (a) an additional direct (i.e. non-beam) heating mechanism has to be present, and (b) considering that the bolometric emission originates mainly from deeper atmospheric layers, conduction or waves are required as additional energy transport mechanisms.
Modeling the effect of temperature variability on malaria control strategies
Authors: Garba Salisu M. , Danbaba Usman A.
Published: November 2020

In this study, a non-autonomous (temperature dependent) and autonomous (temperature independent) models for the transmission dynamics of malaria in a population are designed and rigorously analysed. The models are used to assess the impact of temperature changes on various control strategies. The autonomous model is shown to exhibit the phenomenon of backward bifurcation, where an asymptotically-stable disease-free equilibrium (DFE) co-exists with an asymptotically-stable endemic equilibrium when the associated reproduction number is less than unity. This phenomenon is shown to arise due to the presence of imperfect vaccines and disease-induced mortality rate. Threshold quantities (such as the basic offspring number, vaccination and host type reproduction numbers) and their interpretations for the models are presented. Conditions for local asymptotic stability of the disease-free solutions are computed. Sensitivity analysis using temperature data obtained from Kwazulu Natal Province of South Africa [K. Okuneye and A.B. Gumel. Mathematical Biosciences 287 (2017) 72–92] is used to assess the parameters that have the most influence on malaria transmission. The effect of various control strategies (bed nets, adulticides and vaccination) were assessed via numerical simulations.
COVID-19 pandemic control: balancing detection policy and lockdown intervention under ICU sustainability
Authors: Charpentier Arthur , Elie Romuald , Laurière Mathieu , Tran Viet Chi
Published: November 2020

An extended SIR model, including several features of the recent COVID-19 outbreak, is considered: the infected and recovered individuals can either be detected or undetected and we also integrate an intensive care unit (ICU) capacity. We identify the optimal policy for controlling the epidemic dynamics using both lockdown and detection intervention levers, and taking into account the trade-off between the sanitary and the socio-economic cost of the pandemic, together with the limited capacity level of ICU. With parametric specification based on the COVID-19 literature, we investigate the sensitivities of various quantities on the optimal strategies. The optimal lockdown policy is structured into 4 phases: First a quick and strong lockdown intervention to stop the exponential growth of the contagion; second a short transition to reduce the prevalence of the virus; third a long period with full ICU capacity and stable virus prevalence; finally a return to normal social interactions with disappearance of the virus. The optimal scenario avoids the second wave of infection, provided the lockdown is released sufficiently slowly. Whenever massive resources are introduced to detect infected individuals, the pressure on social distancing can be released, whereas the impact of detection of immune individuals reveals to be more moderate.
Control of Nipah virus outbreak in commercial pig-farm with biosecurity and culling
Authors: Das Samhita , Das Pritha , Das Parthasakha
Published: November 2020

A coupled pig-human Nipah virus disease model is studied in a commercial farm to understand dynamics of disease spillover from pig to human. To portray the specific scenario, two parameters representing biosecurity level and selective culling are included in the system. Along with standard equilibrium analysis, backward and Hopf bifurcation phenomena are demonstrated analytically and numerically. Optimal control of culling alone and also with other controls for the minimization of loss are discussed. It is observed that, irrespective of its application rate, culling is more effective in presence of other controls. Parameter sensitivity analysis of system solution has been used to identify significant parameters for the change of disease dynamics. Sensitivity test is also performed on the objective function of optimal control problem, which singled out crucial parameters influencing the economic loss of farm-owner. Based on this study, some strategies regarding application of various controls are suggested.
Biofumigation to protect oilseed crops: focus on management of soilborne fungi of sunflower
Authors: Ait-Kaci Ahmed Neïla , Dechamp-Guillaume Grégory , Seassau Célia
Published: November 2020

Sunflower (Helianthus annuus L.) is one of the three most productive oilseed crops worldwide. Soilborne diseases limit yields and are challenging to manage. The fungi Verticillium dahliae, Sclerotinia sclerotiorum and Macrophomina phaseolina can survive in the soil for many years and spread. Following the ban on fumigants, biofumigation, which consists of growing, chopping and incorporating a Brassicaceae cover crop to allow biocidal compounds production in the soil, may be an alternative. Biocidal effects of the hydrolysis of glucosinolate into active compounds, such as isothiocyanates, have been shown in laboratory studies, but the effectiveness of biofumigation varies more in the field. The present study reviews the main factors that determine effective biofumigation to protect sunflower. Since the toxicity of isothiocyanates to pathogens varies widely among the latter, we reviewed studies that assessed the suppressive effect of products of glucosinolate hydrolysis on V. dahliae, S. sclerotiorum and M. phaseolina. Farmers can use many mechanisms to increase isothiocyanate production, which may protect sunflower crop effectively. Increasing biomass production and chopping the cover crop during mild temperatures and before rainy periods could increase biofumigation effectiveness. Further field experiments are needed to confirm the potential of biofumigation to control soilborne diseases of sunflower and assess potential disservices to beneficial soil communities, given their potential key role in the control of soilborne pathogens.
Demenz – Herausforderung Menschlichkeit
Authors: Maus Manuel
Published: November 2020

Mit dem Älterwerden der Bevölkerung nimmt auch die Demenz einen immer größeren Einfluss auf die Versorgung von Erkrankten. Wie sieht dabei die Versorgung von Menschen mit Demenz speziell auf der Intensivstation aus? Der folgende Beitrag gibt einen Einblick in die komplexe Arbeit mit Demenzerkrankten, die auf einer Intensivstation medizinisch versorgt werden müssen. Dabei soll nicht die Intensivmedizin im Mittelpunkt stehen, sondern die Wünsche und Bedürfnisse von demenziell erkrankten Menschen und ihren Angehörigen. – Autor Manuel Maus belegte mit seinem Beitrag beim 21. Thieme intensiv-Pflegepreis den 4. Platz.
Heritage education under evaluation: the usefulness, efficiency and effectiveness of heritage education programmes
Authors: Castro-Calviño Leticia , Rodríguez-Medina Jairo , López-Facal Ramón
Published: November 2020

The evaluation of programmes is necessary in order to improve their implementation and development. This paper includes the results of the evaluation of a heritage education programme entitled Patrimonializarte. It was carried out over the course of one academic year with six groups of early years, primary and secondary schoolchildren from two schools in Galicia (Spain). A holistic conception of heritage was assumed, and the evaluations of the opinion groups were gathered, analysing those of 59 direct and indirect agents (teachers, families, local heritage managers and members of the local authorities. The data were collected via questionnaires with open responses and discourse analysis was performed on the responses. The most significant results show that: (a) the teachers valued the methodology and the objectives achieved extremely positively; (b) the families particularly valued the significant learning achieved by their children regarding elements of local heritage; and (c) the local authorities and heritage managers valued the programme as it has demonstrated the need for more collaboration with schools. The programme analysed has been shown to be useful, efficient and effective and has achieved a (largely unexpected) impact on the families involved and on the local community.
Comment on “Time-dependent coupled harmonic oscillators” [J. Math. Phys. 53, 052101 (2012)]
Authors: Moya-Cessa H. M. , Récamier J.
Published: November 2020

Macedo and Guedes [J. Math. Phys. 53, 052101 (2012)] showed recently how to solve a system of coupled harmonic oscillators with time dependent parameters. We show here that the way in which they got rid of the time dependent masses is incorrect and some terms are missing in their transformed Hamiltonian. We also show a correct way of eliminating the time dependent masses from the Hamiltonian.
Adaptive 3D convolutional neural network-based reconstruction method for 3D coherent diffraction imaging
Authors: Scheinker Alexander , Pokharel Reeju
Published: November 2020

We present a novel adaptive machine-learning based approach for reconstructing three-dimensional (3D) crystals from coherent diffraction imaging. We represent the crystals using spherical harmonics (SH) and generate the corresponding synthetic diffraction patterns. We utilize 3D convolutional neural networks (CNNs) to learn a mapping between 3D diffraction volumes and the SH, which describe the boundary of the physical volumes from which they were generated. We use the 3D CNN-predicted SH coefficients as the initial guesses, which are then fine-tuned using adaptive model-independent feedback for improved accuracy. We also adaptively tune the locations, intensities, and decay rates of collections of radial basis functions in order to reproduce the non-uniform internal structure of 3D objects and demonstrate the method for a synthetic volume that has an internal void and a density ramp.
Variable beam entrance Faraday cup system for pulsed electron beam current profile characterization
Authors: Huo Weijie , Hu Jing , Qin Ling , Cao Xiaotong , Zhao Wansheng
Published: November 2020

A high accuracy variable beam entrance Faraday cup (VBEFC) system is designed in this work. The presented VBEFC system is designed for the beam current profile measurement of the transient hollow cathode discharge (THCD) generated pulsed electron beam, which is a new source of high energy flux for metallic material processing. By proper designs of the beam entrance array, fast response electron collector, grounding, and shielding, this VBEFC system is capable of determining the radial profile and its temporal evolution of the THCD generated electron beam. The results of the electron beam current and current density distributions collected at varying radial locations and times under multiple voltages are presented in this paper. The experimental results show that both the amplitude and the current density of the THCD electron beam at a given radius always increased with the increase in the accelerating voltage, which is coincident with the self-focused propagation of the electron beam promoted by the voltage.
Dispersion engineering of superconducting waveguides for multi-pixel integration of single-photon detectors
Authors: Elshaari Ali W. , Iovan Adrian , Gyger Samuel , Zadeh Iman Esmaeil , Zichi Julien , Yang Lily , Steinhauer Stephan , Zwiller Val
Published: November 2020

We use dispersion engineering to control the signal propagation speed in the feed lines of superconducting single-photon detectors. Using this technique, we demonstrate time-division-multiplexing of two-pixel detectors connected with a slow-RF transmission line, all realized using planar geometry requiring a single lithographic step. Through studying the arrival time of detection events in each pixel vs the fabricated slow-RF coplanar waveguide length, we extract a delay of 1.7 ps per 1 μm of propagation, corresponding to detection signal speeds of ∼0.0019c. Our results open an important avenue to explore the rich ideas of dispersion engineering and metamaterials for superconducting detector applications.
Slow propagation of 2 GHz acoustical waves in a suspended GaAs phononic waveguide on insulator
Authors: Modica Giuseppe , Zhu Rui , Horvath Robert , Beaudoin Gregoire , Sagnes Isabelle , Braive Rémy
Published: November 2020

Optoelectronic oscillators have dominated the scene of microwave oscillators in the last few years thanks to their great performances regarding frequency stability and phase noise. However, miniaturization of such devices is an up-to-date challenge. Recently, devices based on a phonon–photon interaction have gathered a lot of interest thanks to their extreme compactness and working frequency directly in the GHz. In this frame, a still-missing element to obtain long-term frequency stability performances is an on-chip delay within the feedback loop. Here, we experimentally show filtering and slow propagation of 2 GHz acoustic waves on a Gallium Arsenide membrane heterogeneously integrated on a silicon wafer. By engineering the dispersion of an acoustical waveguide, we evidence a group velocity below 1000 m/s for the mode able to propagate. Thus, an integrated delay implementation is at reach for potential improvement of opto-acoustic devices such as optomechanical oscillators or wireless applications.
Measurements of channel erosion of Hall thrusters by laser-induced fluorescence
Authors: Duan Xingyue , Guo Dawei , Cheng Mousen , Yang Xiong , Guo Ning
Published: November 2020

The ion velocities within the discharge channel of the 600 W magnetically shielded and unshielded Hall thrusters are measured by the laser-induced fluorescence technique to quantitatively evaluate the erosion of the channel walls. Visual inspection of the magnetically shielded Hall thruster has qualitatively indicated that the discharge channel has been successfully shielded from the bombarding of the plasma, while the erosion occurs in the unshielded counterpart. In addition, the ion velocities along the thruster centerline indicate that the voltage utilization efficiency of MSHT-600 is higher than that of USHT-600 and comparable to the state-of-the-art BHT-600 thruster. Furthermore, measurements performed inside the discharge channel show that the ions deep inside the channel impact the channel walls backward in the shielded thruster, while forward in the unshielded one. Moreover, the plasma potential along the channel walls remains as high as the anode potential in the shielded thruster, while it dramatically decreases in the unshielded one. When accounting for the sheath potential acceleration, the maximum erosion rate of the inner and outer walls of USHT-600 is 1.3 and 3.1 μm/h, respectively, based on the plasma parameters of SPT-100, while the maximum value of the weighted average erosion rate of MSHT-600 is 0.08 and 0.04 μm/h, respectively, for two cases of the ion number density. Compared to the erosion rate of SPT-100, it is qualitatively and quantitatively confirmed that strong shielding of the discharge channel is realized and high performance is maintained in the designed thruster with a magnetically shielded configuration.
Optically triggered multilevel resistive switching characteristics of Cu/MoS2/AlN/ITO bilayer memory structure
Authors: Sharma Shubham , Kumar Anuj , Dutta Shankar , Kaur Davinder
Published: November 2020

In this work, the tunable resistive switching (RS) functionality of a Cu/MoS2/AlN/ITO nanostructured device is systematically investigated in dark and white light illumination. The device exhibits bi-state RS behavior in the dark ambient, whereas light illumination induces an extra intermediate resistance state and provides controllable tri-state RS characteristics. A conceptual model is proposed and discussed to elucidate the origin of the switching behavior of two resistance states and multiple resistance states of the device. Under the dark ambient condition, the high resistance state and the low resistance state in the device could be ascribed to the formation/rupture of a Cu metallic filamentary path between the electrodes. However, the formation of an additional ionic filament via trapping/detrapping of electrons in nitride-sulfide-related vacancies along with the Cu metallic filament is responsible for the tri-state switching under the light illumination. Interestingly, the variation of SET voltage with applied light intensity has also been demonstrated. The calculated value of the temperature coefficient and temperature dependency of resistance in various resistance states confirms the existence of the proposed model. The device performed a good undispersed endurance up to 1.5 × 103 cycles and stable retention over 103 s at room temperature. This optical activity dependent functionality of the device provides a possibility to extend resistive switching-based nonvolatile random access memory applications to the optical domain such as imaging sensors, photodetectors, and optoelectronic switches.
Interplay of intrinsic and extrinsic states in pinning and passivation of m-plane facets of GaN n-p-n junctions
Authors: Freter L. , Wang Y. , Schnedler M. , Carlin J.-F. , Butté R. , Grandjean N. , Eisele H. , Dunin-Borkowski R. E. , Ebert Ph.
Published: November 2020

Intrinsic and extrinsic pinning and passivation of m-plane cleavage facets of GaN n-p-n junctions were investigated by cross-sectional scanning tunneling microscopy and spectroscopy. On freshly cleaved and clean p-type GaN(101¯0) surfaces, the Fermi level is found to be extrinsically pinned by defect states, whereas n-type surfaces are intrinsically pinned by the empty surface state. For both types of doping, air exposure reduces the density of pinning states and shifts the pinning levels toward the band edges. These effects are assigned to water adsorption and dissociation, passivating intrinsic and extrinsic gap states. The revealed delicate interplay of intrinsic and extrinsic surface states at GaN(101¯0) surfaces is a critical factor for realizing flatband conditions at sidewall facets of nanowires exhibiting complex doping structures.