bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of applied stress on exchange bias in ferromagnetic/antiferromagnetic bilayers and the phenomenon of the jump
Authors: Bai Yu-Hao  , Yun Guo-Hong  , B.Narsu  ,   (1)内蒙古大学物理科学与技术学院，呼和浩特  010021; (2)内蒙古大学物理科学与技术学院，呼和浩特  010021；内蒙古师范大学物理与电子信息学院，内蒙古自治区功能材料物理与化学重点实验室，呼和浩特  010022; (3)内蒙古师范大学物理与电子信息学院，内蒙古自治区功能材料物理与化学重点实验室，呼和浩特  010022
Published: December 2020

Using the principle of minimal energy and S-W model，the effect of the applied stress on exchange bias in ferromagnetic （FM） / antiferromagnetic （AFM） bilayers has been investigated.When the applied field is absent，according to the relation between the energy of the system and the orientation of ferromagnetic magnetization， the system will be in monostable state or bistable state，which is controlled by the competition between the uniaxial anisotropy and the exchange anisotropy.Monostable state or bistable state of the system determine the angular dependence of exchange bias immediately.When the external field is applied along the intrinsic easy axes and intrinsic hard axes， it is found by analyzing the magnetization processes that one of the switching field of the hysteresis loop shows a an abrupt change，while the other is kept constant，and consequently the exchange bias field and the coercivity will appear a jump phenomenon.The numerical calculations indicate that both the exchange bias field and the coercivity are larger in the magnitude at the points of the jump.Both the magnitude and the orientation of the applied stress will significantly affect the exchange bias by making a transition between monostable state and bistable state in the system.This transition induces a significant change in angular dependence of the exchange bias. Our results demonstrate that the applied stress is a viable way to control and tune the exchange bias of the FM/AFM bilayers.
Ferromagnetic-antiferromagnetic transition and resistivity variation of oxygen-deficient La0.5Ca0.5MnO3 samples
Authors: Ma Yu-Bin  ,   北京大学物理学院, 北京  100871
Published: December 2020

We have investigated the influence of oxygen vacancies on electronic transport and magnetic property of polycrystalline bulk La0.5Ca0.5MnO3 （LCMO）. With increasing content of oxygen vacancy, its resistivity at high temperature increases monotonically and follows the adiabatic small-polaron model. The resistivity at low temperature first deereases, then increases, and has the behavior of dR/dT>0 evidently. The resistivity at low temperature becomes insulating at last. Increasing the oxygen vacancies depresses the appearance of antiferromagnetic phase. As a result, antiferromagnetic transition does not occurs in oxygen-deficient LCMO samples. On more increasc of oxygen vacancies, ferromagnetic phase will eventually be suppressed.
N-type window layer and its application in high deposition rate microcrystalline silicon solar cells
Authors: Zhang Xiao-Dan  , Zhao Ying  , Sun Fu-He  , Wang Shi-Feng  , Han Xiao-Yan  , Wei Chang-Chun  , Sun Jian  , Geng Xin-Hua  , Xiong Shao-Zhen  ,   南开大学光电子薄膜器件与技术研究所，南开大学光电子薄膜器件与技术天津市重点实验室，光电信息技术科学教育部重点实验室（南开大学，天津大学），天津  300071
Published: December 2020

N-type phosphors doping layer as the window layer of microcrystalline silicon solar cells has been fabricated using conversional radio frequency plasma enhanced chemical vapor deposition. Because of hole and electron mobilities are of the same order for microcrystalline silicon thin film, microcrystalline silicon solar cells based on n-type doping layer as the window layer almost show the same efficiency as microcrystalline silicon solar cells based on p-type doping layer as the window layer. In addition, the results of quantum efficiency are also consistent with the I-V measurement results. Bilateral Raman measurement results using laser light of different wavelength indicated that p/i or n/i interface incubation layer has a disadvantageous influence on the current density of the solar cells. Through the optimization of n/i interface incubation layer, glass/ZnO/n/i/p/Al microcrystalline silicon solar cell with 7.7% conversion efficiency has been fabricated.
Systhesis of C59N and C19N crystals
Authors: Wang Zhen-Xia  , Zhu Jian-Kang  , Ren Cui-Lan  , Zhang Wei  ,   (1)中国科学院上海应用物理研究所，上海  201800; (2)中国科学院上海应用物理研究所，上海  201800；中国科学院研究生院，北京  100049
Published: December 2020

We find that C59N and C19N crystals can be synthesized by slow evaporation of C60 solvent in the atmosphere. It opens up a new and efficient route for the preparation and study of various kinds of Cn（n≤59）N crystals materials.
Precise correction for the troposphere target location error based on lidar
Authors: Wang Min  , Hu Shun-Xing  , Fang Xin  , Wang Shao-Lin  , Cao Kai-Fa  , Zhao Pei-Tao  , Fan Guang-Qiang  , Wang Ying-Jian  ,   (1)中国科学院安徽光学精密机械研究所大气光学中心，合肥  230031; (2)中国科学院安徽光学精密机械研究所大气光学中心，合肥  230031；中国科学院研究生院，北京  100049
Published: December 2020

In a laser target positioning system, to correct the location error is essential for improving the measurement precision. In this paper, a novel method of correcting the tropospheric target location error in utilizing pure rotation lidar is presented. The vertical profiles of atmospheric refractive index are deduced by the pure rotation return signals of N2 and O2, which are detected by the pure Raman lidar. Then, the refraction angle and elevation orientation errors at different altitude are corrected based on error correcting theory. The results indicate that the target location error are well corrected by making use of the atmospheric refractive index which is detected by pure rotation lidar. At the same altitude, the target refraction angle and elevation orientation errors decrease as the visual angle increases. When the visual angle is 10°, the refraction angle of the target at 8 km reaches 3.15′ and the elevation orientation error is 14.55 m. When it is 30°, the refraction angle of the target at the same altitude is only 0.98′ and the elevation orientation error is 1.19 m.
Preliminary study of effects introduced by the dip angle on IAR
Authors: Shi Run  , Zhao Zheng-Yu  ,   武汉大学电子信息学院，武汉  430079
Published: December 2020

The propagation of ULF waves （0.1—10 Hz） from magnetosphere to the conductive ground is studied in the presence of oblique magnetic field and the analytical solution is obtained. The effects on the parameters of the IAR, such as reflection coefficient, eigenfrequency and attenuation, are analyzed. It is shown by simulation that the change of oblique field results in the corresponding change of the scale length and the ionospheric conductivities. Along with the decrease of dip angle, the eigenfrequency declines and so does the attenuation of IAR. The conductivity corresponding to the maximum attenuation also decreases.
A relativistic non-harmonic oscillator potential and pseudospin symmetry
Authors: Zhang Min-Cang  ,   陕西师范大学物理学与信息技术学院，西安  710062
Published: December 2020

A generalized non-harmonic oscillator potential for spin 1/2 particles is studied. The Dirac Hamiltonian contains a scalar and a vector non-harmonic oscillator potentials. Setting either or both combinations Σ(r)=S(r)+V(r) and Δ(r)=V(r)-S(r) to zero, analytical solutions for bound states of the corresponding Dirac equation are found. The eigenenergies and wave functions are presented, showing the pseudospin symmetry exists exactly.The relations between radial nodes of upper and lower components of the Dirac spinor are obtained.
Quantum properties of the entangled coherent light field under the anti-Jaynes-Cummings model
Authors: Zhang Ying-Jie  , Xia Yun-Jie  , Ren Ting-Qi  , Du Xiu-Mei  , Liu Yu-Ling  ,   曲阜师范大学物理工程学院,曲阜  273165
Published: December 2020

A two-level atom drvien by a strong classical field interacts with a single-mode light field, and the interaction between the atom and the light field can turn into an effective anti-Jaynes-Cummings model under the conditions of strong driving and large detuning. In this paper, we mainly study the two-mode entangled coherent light field in this model, in which one mode of the entangled coherent light field interacts with a two-level atom driven by a strong classical field. During the evolution of the total system, we make a selective measurement on the atom. Through tuning the evolution time and the parameter of the coherent field, we can easily control the quantum statistical properties of the other mode of the entangled light fields and generate the expected non-classical light field in a longer interaction time and a wider region of coherent parameter.
The generalized Stefan-Boltzmann’s law of Dilaton-Maxwell non-stationary black hole
Authors: Meng Qing-Miao  , Jiang Ji-Jian  , Liu Jing-Lun  , Deng De-Li  ,   菏泽学院物理系,菏泽  274015
Published: December 2020

Using entropy density near event horizon of the non-stationary Dilaton-Maxwell black hole, the instantaneous emission flux is calculated, and we come to a conclusion that the instantaneous emission flux of blank hole in any direction at any time is always proportionate to the quartic power of temperature of the event horizon of black hole in that direction. It is found that the coefficient of generalized Stefan-Boltzmann is no longer a constant, but a dynamic proportional coefficient related to the rate of change of event horizon, the structure of space-time near event horizon and the radiation absorption coefficient of black hole. It shows that an inner relation between the gravitational field around black hole and its thermal radiation must exist.
Adaptive synchronization and anti-synchronization of two different chaotic systems
Authors: Cai Na  , Jing Yuan-Wei  , Zhang Si-Ying  ,   (1)东北大学信息科学与工程学院，沈阳  110004; (2)东北大学信息科学与工程学院，沈阳  110004;青岛大学复杂性科学研究所，青岛  266071
Published: December 2020

Chaos synchronization and anti-synchronization of two chaotic systems with different structures are investigated. When the parameters are known in advance, the synchronization and anti-synchronization are realized by the active control. The method of designing controllers with active control is generalized. When the parameters are completely unknown, the adaptive controllers and the adaptive laws of parameters are given based on the Lyapunov stability theory and adaptive control method, which realizes adaptive synchronization and anti- synchronization of two different chaotic systems, and identifies the unknown parameters. The drive system and response system are interchanged during the controller designing. The relationship of the controllers and the adaptive laws before and after the interchangement are investigated. The numerical simulation results verify the effectiveness of the proposed scheme.
An improved method for implementation of wavelet transform utilizing switched-current filters
Authors: Zhao Wen-Shan  , He Yi-Gang  ,   湖南大学电气与信息工程学院，长沙  410082
Published: December 2020

A new scheme of implementing wavelet transform using switched-current filters is proposed in this paper. Based on approximation theory of network function, the basic wavelet function is synthesized with the sum of rational fraction obtained by a systematic algorithm. And then the basic wavelet function filter is implemented by a parallel structure of switched-current circuits. Herein, the first derivative of Gaussian function is selected as an example with the construction procedure of approximation network and structure of switched-current filters elaborated. The filter network employs six biquadratic switched-current filters in a parallel connection, in which the S2I memory cell is used as the core of the filter. Theoretical analysis and simulation result show that the proposed scheme is superior to the original method in approximation precision, system stability and circuit performance.
Stability of traditional neutron magic numbers
Authors: Ding Bin-Gang  , Zhang Da-Li  , Lu Ding-Hui  ,   (1)浙江大学近代物理中心，杭州  310000; (2)浙江湖州师范学院理学院，湖州  313000
Published: December 2020

By systematically analyzing the single particle level and the occupation probability near the Fermi surface，and the rule of nuclear particle number deviations with proton numbers for N=8，20，28，50，82，126 neutron chains within the relativistic mean-field model with BCS theory，we have discussed the stability of the shell structure for the traditional neutron magic in the whole range of nuclear spectrum from neutron line to proton line，and predicted that traditional neutron magic number effect shall possibly disappear only in light neutron-rich nuclei. Our results are also compared with the results of other recent reports.
Image thresholding segmentation based on two-dimensional minimum Tsallis-cross entropy
Authors: Tang Ying-Gan  , Di Qiu-Yan  , Zhao Li-Xing  , Guan Xin-Ping  , Liu Fu-Cai  ,   燕山大学工业计算机控制工程河北省重点实验室，秦皇岛  066004
Published: December 2020

Image thresholding segmentation method based on two-dimensional minimum Tsallis-cross entropy is proposed by utilizing the non-extensive property of Tsallis entropy in the paper. Firstly, the two-dimensional Tsallis-cross entropy is given, then the particle swarm optimization is used to search the best two-dimensional threshold vector by minimizing the two-dimensional Tsallis-cross entropy. The proposed method not only considers the spatial information of pixels, but also the interaction between the object and the background. Its segmentation performance is superior to thresholding methods using Shannon entropy and minimum one-dimensional Tsallis-cross entropy. Experimental results show that the proposed method can give good segmentation results with less computation time.
Computer generated holography based on Fourier transform using conjugate symmetric extension
Authors: Huang Su-Juan  , Wang Shuo-Zhong  , Yu Ying-Jie  ,   (1)上海大学机电工程与自动化学院，上海  200072; (2)上海大学通信与信息工程学院，上海  200072；上海大学特种光纤与光接入网省部共建重点实验室，上海  200072
Published: December 2020

A new computer generated holography (CGH) algorithm based on Fourier transform is proposed. The complex amplitude of the light wave to be recorded is extended to produce a conjugate symmetric function. The function is then Fourier transformed to generate a real valued distribution containing both the amplitude information and the phase information of the light wave. The obtained real distribution is coded to give a gray-scale hologram，which can be used to reconstruct the original light wave. Unlike the existing CGH algorithms based on interference of object and reference light waves，the proposed method does not require simulatingthe interference to produce the hologram. The algorithm is highly efficient，and can produce good results both in digital and electroholographic reconstruction. Theoretical and experimental results are presented to verify the validity of the method.
Influence of correlated white noises on the immunity of an anti-tumor system
Authors: Bie Meng-Jie  , Zhong Wei-Rong  , Chen Di-Hu  , Li Li  , Shao Yuan-Zhi  ,   (1)中山大学光电材料与技术国家重点实验室，广州  510275; (2)中山大学光电材料与技术国家重点实验室，广州  510275；香港浸会大学物理系非线性研究中心，香港; (3)中山大学肿瘤防治中心，华南肿瘤学国家重点实验室，广州  510060
Published: December 2020

We introduced two correlated Gaussian multiplicative white noises into the Logistic growth model for an anti-tumor system subject to immune surveillance. Considering various active thresholds to initiate the immunity of the anti-tumor system, we made numerical simulations to investigate how the intensity λ of two correlated white noises influences the immune effect of an anti-tumor system. Our numerical results reveal that the correlation intensity λ has an optimal value, at which the anti-tumor system will achieve functionally the best immunity.
Nonlinear processes in strong ultrashort pulse pumped semiconductor optical amplifier
Authors: Liu Mao-Tong  , Yang Ai-Ying  , Sun Yu-Nan  ,   北京理工大学信息科学技术学院光电工程系，北京  100081
Published: December 2020

A theoretical model of semiconductor optical amplifier (SOA) is presented with carrier density pulsation (CDP)，free-carrier absorption (FCA)，stimulated emission (SE)，two-photon absorption (TPA)，spectral hole burning (SHB) and ultrafast nonlinear refraction (UNR) taken into account. The model is proved by comparing with the reported experimental results. The prevailing SOA model is revised. The influences of FCA and TPA processes on ultrashort strong optical pulses are analysed. When the strong optical pulse with several-picosecond pulsewidth is injected into the SOA operating under the transparency current，the intensity characteristics of the optical pulse are mainly influenced by TPA and FCA. As a result of taking the FCA effect into account，the intensity transmission characteristics of 200fs optical pulses obtained by the new model basically agree with the experimental results. It broadens the applicability of the model.
From Turnip to Onion: Humanities, Curiosities, and Anecdotes of Hallux Valgus
Authors: Rueda Cristóbal Suárez , Abián María Herrera , Limón Carlos Martínez , Macera Armando
Published: December 2020

Background

We sought to highlight the humanistic aspect of hallux valgus.

Methods

We conducted a bibliographic search between 2013 and 2017 of scientific, historic, and humanistic articles, in search of the anthropological dimension of hallux valgus. Museums and works of art by relevant painters were analzyed for the presence of hallux valgus.

Results

We showcase the linguistic origin of the terms related to hallux valgus, the evolution of its incidence depending on the footwear and social habits throughout history, the presence of hallux valgus in the work of great painters, and some other curiosities of this pathology.

Conclusions

The knowledge of the humanistic aspect of pathologies we treat, if not imperative for its proper surgical resolution, can help to improve the understanding of them.
Desmoid Tumors of the Foot: A Retrospective Study of Four Patients
Authors: Dürr Hans R. , Wirth Laura , Baur-Melnyk Andrea , Knösel Thomas , Roeder Falk , Jansson Volkmar , Klein Alexander
Published: December 2020

Background

Desmoid-type fibromatosis (DF) is an aggressive (myo)fibroblastic neoplasm with an infiltrative growth pattern and a tendency for local recurrence. It is rarely seen at the foot. The aim of this retrospective study was to analyze clinical presentation, therapy, and outcomes in a consecutive series of four patients with DF at the foot.

Methods

From 1994 to 2014, four patients had been surgically treated. The resection margin was marginal or even intralesional in all. One patient already had local recurrence at first presentation. The end point was either local recurrence or progression of residual disease.

Results

The mean patient age was 27 years. In one patient, marginal excision healed the disease. In another patient, local recurrence after marginal resection necessitated distal phalanx amputation. Two other patients showed stable disease after either adjuvant radiotherapy or treatment with nonsteroidal anti-inflammatory drugs and tamoxifen.

Conclusions

If surgery is necessary, operative margins are less important than keeping function for the patient. Radiotherapy might be an option to avoid major amputation. The role of adjuvant radiotherapy is controversially discussed. A watchful wait-and-see policy seems to be justified by the published data but may be difficult for DF at the foot.
Identification of biomarkers associated with clinical severity of chronic obstructive pulmonary disease
Authors: Zhang Jie , Zhu Changli , Gao Hong , Liang Xun , Fan Xiaoqian , Zheng Yulong , Chen Song , Wan Yufeng
Published: December 2020

We sought to identify the biomarkers related to the clinical severity of stage I to stage IV chronic obstructive pulmonary disease (COPD). Gene expression profiles from the blood samples of COPD patients at each of the four stages were acquired from the Gene Expression Omnibus Database (GEO, accession number:GSE54837). Genes showing expression changes among the different stages were sorted by soft clustering. We performed functional enrichment, protein–protein interaction (PPI), and miRNA regulatory network analyses for the differentially expressed genes. The biomarkers associated with the clinical classification of COPD were selected from logistic regression models and the relationships between TLR2 and inflammatory factors were verified in clinical blood samples by qPCR and ELISA. Gene clusters demonstrating continuously rising or falling changes in expression (clusters 1, 2, and 7 and clusters 5, 6, and 8, respectively) from stage I to IV were defined as upregulated and downregulated genes, respectively, and further analyzed. The upregulated genes were enriched in functions associated with defense, inflammatory, or immune responses. The downregulated genes were associated with lymphocyte activation and cell activation. TLR2, HMOX1, and CD79A were hub proteins in the integrated network of PPI and miRNA regulatory networks. TLR2 and CD79A were significantly correlated with clinical classifications. TLR2 was closely associated with inflammatory responses during COPD progression. Functions associated with inflammatory and immune responses as well as lymphocyte activation may play important roles in the progression of COPD from stage I to IV.TLR2andCD79Amay serve as potential biomarkers for the clinical severity of COPD.TLR2andCD79Amay also serve as independent biomarkers in the clinical classification in COPD. TLR2 may play an important role in the inflammatory responses of COPD.
Quantitative comparison of the mRNA content of human iPSC‐derived motor neurons and their extracellular vesicles
Authors: Otake Kentaro , Adachi‐Tominari Keiko , Nagai Hiroaki , Saito Masayo , Sano Osamu , Hirozane Yoshihiko , Iwata Hidehisa
Published: December 2020

Extracellular vesicles (EVs) contain various cargo molecules, including RNAs and proteins. EVs, which include exosomes, are predicted to be suitable surrogates of their source cells for liquid biopsy to measure biomarkers. Several studies have performed qualitative comparisons of cargo molecule repertoires between source cells and their EVs. However, quantitative comparisons have not been reported so far. Furthermore, many studies analyzed microRNAs or proteins in EVs, but not mRNAs. In this study, we analyzed mRNAs in motor neurons and their EVs. Normal human‐induced pluripotent stem cells were differentiated into motor neurons, and comprehensive analysis of mRNAs in the cells and their EVs was performed by RNA sequencing. Differential analysis between cellular and EV mRNAs was performed by edgeR after normalization of read count. The results suggest that signatures in the abundance of EV mRNAs were different from those of cellular mRNAs. Comparison of intracellular vesicle and EV mRNA abundance showed negatively and positively biased genes in the EVs. Gene Ontology analysis revealed that the genes showing negatively biased abundance in the EVs were enriched in many functions regarding neuronal development. In contrast, the positively biased genes were enriched in functions regarding cellular metabolism and protein synthesis. These results suggest that mRNAs in motor neurons are loaded into EVs to regulate certain mechanisms, which are yet to be elucidated.
Prediction Method of Three‐Dimensional Crack Propagation Path Based on Deep Learning Application
Authors: Wang Junxia , Zheng Yuanjie , Luo Rong , Ma Jun , Peng Yingjie , Aslam Sehrish , Jia Weikuan
Published: December 2020

In engineering, most structural components suffer from local damage in service or fabrication. Under different loading conditions, such local damage will further expand to large cracks and structural collapse. For ensuring longevity and reliability, the study of brittle crack growth is important. In structural damage prediction, various methodologies are commonly used and have demonstrated success in the past. Most traditional simulation methods, however, have the problems of large calculation quantities and long calculation times. At the same time, the mutual influence of crack opening stress and crack image on crack widening is rarely considered in existing works based on the deep learning framework. Herein, a deep learning model is developed to predict the spread of fracture of brittle materials under stress to improve the aforementioned problems. By developing a nonlinear relationship between crack stress and damage effects, this approach predicts crack growth, thus avoiding the loss of required information on crack growth behavior. The model emphasizes repeatability and extensibility, which is verified using extended finite element method (XFEM) Abaqus software through multiple sets of material crack data generated. This model's potential applications are material design and evaluation of residual life.
Self‐Driven Perovskite Narrowband Photodetectors with Tunable Spectral Responses
Authors: Wang Jian , Xiao Shuang , Qian Wei , Zhang Kai , Yu Jun , Xu Xiuwen , Wang Gaopeng , Zheng Shizhao , Yang Shihe
Published: December 2020

Narrowband photodetectors with tunable spectral responses are highly desirable for applications in image sensing, machine vision, and optical communication. Herein, a filterless and self‐driven perovskite narrowband photodetector (PNPD) based on the defect‐assisted charge collection narrowing (CCN) mechanism is reported, which is enabled by a high‐quality thick perovskite film. By adjusting the halide component of the perovskite layer, the bandgap is successfully modulated and the corresponding narrowband photodetectors show a wide spectral response range from the red to the near‐infrared (NIR), all with full‐widths at half maximum (FWHMs) below 30 nm. Specifically, the methylammonium lead iodide (MAPbI3) narrowband photodetector exhibits a characteristic detection peak at 800 nm with a very low noise current of ≈0.02 pA Hz–1/2, a high specific detectivity up to 1.27 × 1012 Jones, and a fast response speed with rise/fall time of 12.7/6.9 µs. Impressively, these values are among the highest of their kind reported previously, and allow demonstration of narrowband imaging. The excellent performance of self‐driven PNPDs lights up their prospect in high‐efficiency optoelectronic devices without external power sources.
2D THz Optoelectronics
Authors: Mittendorff Martin , Winnerl Stephan , Murphy Thomas E.
Published: December 2020

The terahertz (THz) region of the electromagnetic spectrum spans the gap between optics and electronics and has historically suffered from a paucity of optoelectronic devices, in large part because of inadequate optical materials that function in this spectral range. 2D materials, including graphene and a growing family of related van der Waals materials, have been shown to exhibit unusual optical and electrical properties that can enable diverse new applications in the THz regime. In this review, some of the unusual properties of 2D materials that make them promising for THz applications are explained, the recent work in the field of 2D THz optoelectronics is summarized, and the challenges and opportunities that await this promising new field are outlined.
Switchable Second‐Harmonic Generation of Airy Beam and Airy Vortex Beam
Authors: Liu Yuan , Chen Wei , Tang Jie , Xu Xiaoyi , Chen Peng , Ma Chao‐Qun , Zhang Wang , Wei Bing‐Yan , Ming Yang , Cui Guo‐Xin , Zhang Yong , Hu Wei , Lu Yan‐Qing
Published: December 2020

Airy beam and Airy vortex beam with intriguing characteristics have been extensively studied in linear optics, while their dynamic nonlinear conversion has rarely been explored and remains challenging. Here, through the collaboration of binary mask engineered nonlinear photonic crystal and space‐variant liquid‐crystal geometric phase element, second‐harmonic Airy beam and Airy vortex beam can be generated in a switchable manner. Electrical‐controlled loading of orbital angular momentum (OAM) into fundamental wave unlocks the flexibility of nonlinear process, which is well investigated in theory and further verified by experiment. Wavelength transformation, OAM conversion, and propagation trajectory inflection are realized simultaneously. This offers a convenient and universal strategy for dynamic nonlinear generation and shows great potentials in optical manipulation and information processing.
Transition Metal‐Free Synthesis of Substituted Isothiazoles via Three‐Component Annulation of Alkynones, Xanthate and NH4I
Authors: Li Jian , Li Jiaming , Ji Xiaoliang , Liu Qiang , Chen Lu , Huang Yubing , Li Yibiao
Published: December 2020

A protocol was described to access diverse isothiazoles with functionalization potential via transition metal‐free three‐component annulation of alkynones, potassium ethylxanthate (EtOCS2K) and ammonium iodide (NH4I). A sequential regioselective hydroamination/thiocarbonylation/intramolecular cyclization cascade achieved the efficient formation of consecutive C−N, C−S and N−S bonds in a one‐pot process.

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Quantifying and Comparing Fundamental Loss Mechanisms to Enable Solar‐to‐Hydrogen Conversion Efficiencies above 20% Using Perovskite–Silicon Tandem Absorbers
Authors: Sharma Astha , Beck Fiona J.
Published: December 2020

Photovoltaic (PV)‐based solar hydrogen generation is a promising pathway for the scalable production of renewable fuels. Understanding the limitations of solar‐to‐hydrogen (STH) conversion efficiencies is critical to identify performance limits and conceptualize practical device designs. Herein, the losses in PV‐based solar hydrogen generation systems are quantified and the potential of loss‐mitigation techniques to improve the STH efficiency is assessed. The analysis shows that the two largest losses in an ideal system are current and voltage mismatches due to suboptimal system configurations and energy lost as heat in the PV component. A temperature‐dependent model is developed to evaluate the relative potential of two techniques to mitigate these losses: decoupling the PV system to remove current and voltage matching requirements and thermal integration to use the heat losses from PV to increase the electrolyte temperature and improve the reaction dynamics for water splitting. It is shown that optimal system configuration strategies provide more than three times the STH efficiency increase of thermal integration at high operating temperatures. Combining both techniques results in predicted STH efficiencies approaching 20% for low‐cost perovskite–silicon tandem‐based systems with earth‐abundant catalysts at realistic working temperatures.
Stemphylium blight reduces milling qualities of lentil
Authors: Subedi Maya , Bazghaleh Navid , Caudillo‐Ruiz Kiela , Vandenberg Albert
Published: December 2020

Stemphylium blight (SB) (Stemphylium botryosum) is a major disease of lentil (Lens culinaris Medik.) in many global production regions. In Canada, SB typically occurs after canopy closure in the second half of the growing season when weather conditions become warm and humid. Experiments were carried out to assess the impact of SB disease on milling qualities of lentil. In 2014, milling qualities of red lentils were compared between seed obtained from an uninfected site and those produced at a naturally SB‐infected site. In 2016 and 2017, controlled field experiments were conducted by artificially inoculating the plots with SB conidia at the early flowering stage. Seed yield in the infected plots was reduced by 52, 22, and 30% compared with control plots in 2014, 2016, and 2017, respectively. The percentages of stained and deformed seeds were increased in infected plots in 2016 and 2017. Seeds infected with SB have reduced milling qualities. Dehulling efficiency was reduced by 25.3, 23.0, and 15.9%, and milling recovery was reduced by 23.7, 25.4, and 15.1% compared with the uninfected control plots, respectively, in 2014, 2016, and 2017. Stemphylium blight had minimal impact on football lentil recovery. These results suggest that SB is potentially the leading cause of the reported poor milling quality of Canadian red lentils that reduces the economic value in years when the growing season is favorable for development of SB. These results have major implications for agronomy, pathology, and breeding strategies of the lentil crop in temperate production regions.
Macadamia intercropping into an inefficient adult coffee plantation is economically advantageous
Authors: Perdoná Marcos J. , Soratto Rogério P. , Porto Antonio J. , Pinotti Raquel N.
Published: December 2020

The paper's hypothesis was that intercropping macadamia (Macadamia integrifolia Maiden & Betche) in an Arabica coffee (Coffea arabica L.) plantation would increase land‐use efficiency and economic results. An experiment was conducted in southeastern Brazil to evaluate the planting of macadamia intercropped into a declining adult coffee plantation where trees were pruned, removed, or neither on the payback period compared with a macadamia monoculture. The experiment was arranged in a randomized complete block design with six treatments and four replications. Treatments consisted of four systems of planting macadamia intercropped within a coffee plantation (T1–unpruned coffee trees; T2–side pruning of two coffee trees; T3–stumping of two coffee trees; T4–removal of one coffee tree), and a coffee monocropping and a macadamia monoculture planted where coffee crops were eradicated (macadamia monocropping) as control. We evaluated macadamia plant growth and economic results across four growing seasons and considered three macadamia plant arrangements. At 46 mo after planting, macadamia plants intercropped with unpruned coffee trees had lower plant height (28%) and trunk diameter (63%) than those planted in macadamia monoculture. Treatments T3 and T4 provided greater growth of macadamia plants. Coffee yield losses caused by pruning or removal of coffee trees were not significant, regardless of the macadamia plant arrangement used. The implantation of the macadamia intercropped with an inefficient adult coffee crop proved to be economically more advantageous than the implantation of a macadamia orchard in monoculture.
CHRNB1‐associated congenital myasthenia syndrome: Expanding the clinical spectrum
Authors: Freed Amanda S. , Schwarz Anisha C. , Brei Brianna K. , Clowes Candadai Sarah V. , Thies Jenny , Mah Jean K. , Chabra Shilpi , Wang Leo , Innes A. Micheil , Bennett James T.
Published: December 2020

CHRNB1 encodes the β subunit of the acetylcholine receptor (AChR) at the neuromuscular junction. Inherited defects in the neuromuscular junction can lead to congenital myasthenia syndrome (CMS), a clinically and genetically heterogeneous group of disorders which includes fetal akinesia deformation sequence (FADS) on the severe end of the spectrum. Here, we report two unrelated families with biallelic CHRNB1 variants, and in each family, one child presented with lethal FADS. We contrast the diagnostic odysseys in the two families, one of which lasted 16 years while the other, utilizing rapid exome sequencing, led to specific treatment in the first 2 weeks of life. Furthermore, we note that CHRNB1 variants may be under‐recognized because in both families, one of the variants is a single exon deletion that has been previously described but may not easily be detected in clinically available genetic testing.
Adsorption of SARS‐CoV‐2 Spike Protein S1 at Oxide Surfaces Studied by High‐Speed Atomic Force Microscopy
Authors: Xin Yang , Grundmeier Guido , Keller Adrian
Published: December 2020

The ongoing coronavirus disease 2019 (COVID‐19) pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) represents a serious threat to the health of millions of people. Respiratory viruses such as SARS‐CoV‐2 can be transmitted via airborne and fomite routes. The latter requires virion adsorption at abiotic surfaces and most likely involves the SARS‐CoV‐2 spike protein subunit 1 (S1), which is the outermost point of its envelope. Understanding S1 spike protein interaction with fomite surfaces thus represents an important milestone on the road to fighting the spread of COVID‐19. Herein, high‐speed atomic force microscopy (HS‐AFM) is used to monitor the adsorption of the SARS‐CoV‐2 spike protein S1 at Al2O3(0001) and TiO2(100) surfaces in situ. While the single‐crystalline oxide substrates are chosen to model the native surface oxides of Al‐ and Ti‐based fomites, adsorption is studied in electrolytes that mimic the pH and major ionic components of mucosal secretions and saliva, respectively. Quantitative analysis of the obtained HS‐AFM images indicates that S1 spike protein adsorption at these surfaces is mostly governed by electrostatic interactions with possible contributions from van der Waals interactions. It thus proceeds more rapidly at the TiO2(100) than at the Al2O3(0001) surface.
Accurate Determination of the Quantity and Spatial Distribution of Counterions around a Spherical Macroion
Authors: Chen Jiahui , Bera Mrinal K. , Li Hui , Yang Yuqing , Sun Xinyu , Luo Jiancheng , Baughman Jessi , Liu Cheng , Yao Xuesi , Chuang Steven S. C. , Liu Tianbo
Published: December 2020

The accurate distribution of countercations (Rb+and Sr2+) around a rigid, spherical, 2.9‐nm size polyoxometalate cluster, {Mo132}42−, is determined by anomalous small‐angle X‐ray scattering. Both Rb+and Sr2+ions lead to shorter diffuse lengths for {Mo132} than prediction. Most Rb+ions are closely associated with {Mo132} by staying near the skeleton of {Mo132} or in the Stern layer, whereas more Sr2+ions loosely associate with {Mo132} in the diffuse layer. The stronger affinity of Rb+ions towards {Mo132} than that of Sr2+ions explains the anomalous lower critical coagulation concentration of {Mo132} with Rb+compared to Sr2+. The anomalous behavior of {Mo132} can be attributed to majority of negative charges being located at the inner surface of its cavity. The longer anion–cation distance weakens the Coulomb interaction, making the enthalpy change owing to the breakage of hydration layers of cations more important in regulating the counterion–{Mo132} interaction.
Lanthanide‐Based Molecular Cluster‐Aggregates: Optical Barcoding and White‐Light Emission with Nanosized {Ln20} Compounds
Authors: Gálico Diogo A. , Kitos Alexandros A. , Ovens Jeffrey S. , Sigoli Fernando A. , Murugesu Muralee
Published: December 2020

Counterfeit goods represent a major problem to companies, governments, and customers, affecting the global economy. In order to protect the authenticity of products and documents, optical anti‐counterfeit technologies have widely been employed via the use of discrete molecular species, extended metal–organic frameworks (MOFs), and nanoparticles. Herein, for the first time we demonstrate the potential use of molecular cluster‐aggregates (MCA) as optical barcodes via composition and energy transfer control. The tuneable optical properties for the [Ln20(chp)30(CO3)12(NO3)6(H2O)6], where chp−=deprotonated 6‐chloro‐2‐pyridinol, allow the fine control of the emission colour output, resulting in high‐security level optical labelling with a precise read‐out. Moreover, a unique tri‐doped composition of GdIII, TbIII, and EuIII led to MCAs with white‐light emission. The presented methodology is a unique approach to probe the effect of composition control on the luminescent properties of nanosized molecular material.
Ultra‐Low Molecular Weight Photoswitchable Hydrogelators
Authors: Larik Fayaz Ali , Fillbrook Lucy L. , Nurttila Sandra S. , Martin Adam D. , Kuchel Rhiannon P. , Al Taief Karrar , Bhadbhade Mohan , Beves Jonathon E. , Thordarson Pall
Published: December 2020

Two photoswitchable arylazopyrozoles form hydrogels at a concentration of 1.2 % (w/v). With a molecular weight of 258.28 g mol−1, these are the lowest known molecular weight hydrogelators that respond reversibly to light. Photoswitching of the E‐ to the Z‐form by exposure to 365 nm light results in a macroscopic gel→sol transition; nearly an order of magnitude reduction in the measured elastic and loss moduli. In the case of the meta‐arylazopyrozole, cryogenic transmission electron microscopy suggests that the 29±7 nm wide sheets in the E‐gel state narrow to 13±2 nm upon photoswitching to the predominantly Z‐solution state. Photoswitching for meta‐arylazopyrozole is reversible through cycles of 365 nm and 520 nm excitation with little fatigue. The release of a rhodamine B dye encapsulated in gels formed by the arylazopyrozoles is accelerated more than 20‐fold upon photoswitching with 365 nm light, demonstrating these materials are suitable for light‐controlled cargo release.
TunableegOrbital Occupancy in Heusler Compounds for Oxygen Evolution Reaction**
Authors: Yu Mingquan , Li Guowei , Fu Chenguang , Liu Enke , Manna Kaustuv , Budiyanto Eko , Yang Qun , Felser Claudia , Tüysüz Harun
Published: December 2020

Heusler compounds have potential in electrocatalysis because of their mechanical robustness, metallic conductivity, and wide tunability in the electronic structure and element compositions. This study reports the first application of Co2YZ‐type Heusler compounds as electrocatalysts for the oxygen evolution reaction (OER). A range of Co2YZcrystals was synthesized through the arc‐melting method and theegorbital filling of Co was precisely regulated by varyingYandZsites of the compound. A correlation between theegorbital filling of reactive Co sites and OER activity was found for Co2MnZcompounds (Z=Ti, Al, V, and Ga), whereby higher catalytic current was achieved foregorbital filling approaching unity. A similar trend ofegorbital filling on the reactivity of cobalt sites was also observed for other Heusler compounds (Co2VZ,Z=Sn and Ga). This work demonstrates proof of concept in the application of Heusler compounds as a new class of OER electrocatalysts, and the influence of the manipulation of the spin orbitals on their catalytic performance.
MgO‐Template Synthesis of Extremely High Capacity Hard Carbon for Na‐Ion Battery
Authors: Kamiyama Azusa , Kubota Kei , Igarashi Daisuke , Youn Yong , Tateyama Yoshitaka , Ando Hideka , Gotoh Kazuma , Komaba Shinichi
Published: December 2020

Extremely high capacity hard carbon for Na‐ion battery, delivering 478 mAh g−1, is successfully synthesized by heating a freeze‐dried mixture of magnesium gluconate and glucose by a MgO‐template technique. Influences of synthetic conditions and nano‐structures on electrochemical Na storage properties in the hard carbon are systematically studied to maximize the reversible capacity. Nano‐sized MgO particles are formed in a carbon matrix prepared by pre‐treatment of the mixture at 600 °C. Through acid leaching of MgO and carbonization at 1500 °C, resultant hard carbon demonstrates an extraordinarily large reversible capacity of 478 mAh g−1 with a high Coulombic efficiency of 88 % at the first cycle.
Variance‐constrained H∞ synchronization control of discrete time‐delayed complex dynamical networks: An intermittent pinning approach
Authors: Zhang Jiayi , Wei Guoliang , Ding Derui , Liu Shuai
Published: December 2020

In this paper, the variance‐constrained H∞ synchronization control problem is investigated for a class of discrete time‐delayed complex dynamical networks. Considering the case where a dynamical network cannot achieve the synchronization by itself, the feedback controllers are added to drive the network toward a desired orbit. To further decrease both the frequency of controller update and the energy consumption, an intermittent pinning strategy is developed to control only a small part of the network nodes. The purpose of the addressed synchronization control problem is to design a set of feedback controllers such that the closed‐loop system achieves both the prescribed H∞ disturbance attenuation level and the variance constraints. By resorting to a combination of the Lyapunov stability theory and the switching system approach, a sufficient condition is obtained under which the dynamical network reaches the overall synchronization. Furthermore, the expected gains of the intermittent pinning controllers are parameterized by solving a set of linear matrix inequalities. Finally, a numerical example is exploited to verify the effectiveness of our proposed theoretical results.
Neural stem cell pools in the vertebrate adult brain: Homeostasis from cell‐autonomous decisions or community rules?
Authors: Dray Nicolas , Than‐Trong Emmanuel , Bally‐Cuif Laure
Published: December 2020

Adult stem cell populations must coordinate their own maintenance with the generation of differentiated cell types to sustain organ physiology, in a spatially controlled manner and over long periods. Quantitative analyses of clonal dynamics have revealed that, in epithelia, homeostasis is achieved at the population rather than at the single stem cell level, suggesting that feedback mechanisms coordinate stem cell maintenance and progeny generation. In the central nervous system, however, little is known of the possible community processes underlying neural stem cell maintenance. Recent work, in part based on intravital imaging made possible in the adult zebrafish, conclusively highlights that homeostasis in neural stem cell pools may rely on population asymmetry and long‐term spatiotemporal coordination of neural stem cell states and fates. These results suggest that neural stem cell assemblies in the vertebrate brain behave as self‐organized systems, such that the stem cells themselves generate their own intrinsic niche.
Short review on recent progress in Mn4+‐activated oxide phosphors for indoor plant light‐emitting diodes
Authors: Dhoble Sanjay J. , Priya Ruby , Dhoble N.S. , Pandey O.P.
Published: December 2020

In the modern era, growing number of indoor plants for various purposes, such as vegetation, flowering, and decorations, has increased over the traditional follow‐up trends for plantation. However, the indoor plantation requires different parameters for their growth; among these, light plays a significant role. In order to control the growth of plants using light‐emitting diodes, Mn‐doped oxide phosphors have emerged as promising candidates due to their broad and intense emission bands in the red and far‐red spectral range. In this review article, recent progress on Mn‐doped oxides for indoor plant growth has been reviewed. This review article is mainly divided into three parts. In the first part, different reaction conditions for the synthesis of Mn‐doped oxide phosphors are compared. In the second part, the luminescent and other photometric parameters of these are discussed. The influence of different co‐dopants on the luminescent characteristics has been elucidated in detail. The third part discusses the properties of light‐emitting diodes fabricated using these phosphors for plant growth. The present review article elucidates the synthesis parameters, luminescent properties, and light‐emitting diodes fabricated using Mn‐doped oxide materials for plant growth applications.
A new fluorescence method for detection of famotidine based on polyethyleneimine‐templated Ag nanoclusters
Authors: Shen Yu‐Mang , Tian Rui , Ma Hong‐Yan , Sun Xue‐Hua
Published: December 2020

A rapid, simple, inexpensive fluorescence analysis method for determination of famotidine based on polyethyleneimine (PEI)‐capped Ag nanoclusters (PEI‐Ag NCs) was developed. The study showed that addition of famotidine could cause efficient quenching of PEI‐Ag NC fluorescence, as the presence of famotidine could cause aggregation of Ag NCs and quench its fluorescence. The sensitivity and selectivity of the method were investigated and experimental conditions such as buffer type, pH, temperature, and reaction time were optimized. Under optimized conditions, the results showed a linear profile from 3.7 × 10−8 to 3.7 × 10−5 mol/L, and had a detection limit of 1.6 × 10−9 mol/L (S/N = 3).