bluuebunny/crossref_metadata_2025 huggingface dataset:
Explorando o pensamento computacional no ensino médio: do design à avaliação de jogos digitais
Authors: De França Rozelma , Tedesco Patrícia
Published: June 2020

O ensino do pensamento computacional na educação básica é uma necessidade premente. Contudo, a aprendizagem de conceitos computacionais possui diversos desafios. Neste âmbito, este trabalho apresenta um estudo que visou analisar o impacto da avaliação por pares na aprendizagem do pensamento computacional e na qualidade de jogos produzidos pelos educandos em contraste com uma abordagem tradicional de avaliação da aprendizagem, no contexto de um curso de programação de jogos digitais no ensino médio. Os resultados obtidos sugerem que a adoção da estratégia proposta é benéfica ao aprendizado e pode contribuir com a jogabilidade de games produzidos pelos estudantes.
Mundo virtual Minecraft: uma Experiência no Ensino de Circuitos Digitais
Authors: Cagnini Henry , Charão Andrea , Barcelos Patrícia , De Azevedo Bruno
Published: June 2020

Mundos virtuais têm proporcionado novas experiências no processo de ensino-aprendizagem. Um exemplo de mundo virtual é o do jogo Minecraft, que oferece entretenimento a milhões de usuários e vem despertando o interesse de educadores. Neste trabalho, apresenta-se uma experiência de uso do Minecraft na disciplina de Circuitos Digitais, em uma instituição de ensino superior. Para isso, construiu-se um conjunto de desafios inseridos no mundo virtual, utilizando conceitos de portas lógicas e multiplexadores. Os desafios foram propostos a alunos calouros de Ciência da Computação e Sistemas de Informação. A experiência permitiu levantar impressões, tanto positivas como negativas, sobre a aplicabilidade do Minecraft neste contexto.
Rapid Validation of Telepathology by an Academic Neuropathology Practice During the COVID-19 Pandemic
Authors: Henriksen Jonathan , Kolognizak Teresa , Houghton Tracy , Cherne Steve , Zhen Daisy , Cimino Patrick J. , Latimer Caitlin S. , Scherpelz Kathryn P. , Yoda Rebecca A. , Alpers Charles E. , Chhieng David F. , Keene C. Dirk , Gonzalez-Cuyar Luis F.
Published: June 2020

Context.—

The coronavirus disease 19 (COVID-19) pandemic is placing unparalleled burdens on regional and institutional resources in medical facilities across the globe. This disruption is causing unprecedented downstream effects to traditionally established channels of patient care delivery, including those of essential anatomic pathology services. With Washington state being the initial North American COVID-19 epicenter, the University of Washington in Seattle has been at the forefront of conceptualizing and implementing innovative solutions in order to provide uninterrupted quality patient care amidst this growing crisis.

Objective.—

To conduct a rapid validation study assessing our ability to reliably provide diagnostic neuropathology services via a whole slide imaging (WSI) platform as part of our departmental COVID-19 planning response.

Design.—

This retrospective study assessed diagnostic concordance of neuropathologic diagnoses rendered via WSI as compared to those originally established via traditional histopathology in a cohort of 30 cases encompassing a broad range of neurosurgical and neuromuscular entities. This study included the digitalization of 93 slide preparations, which were independently examined by groups of board-certified neuropathologists and neuropathology fellows.

Results.—

There were no major or minor diagnostic discrepancies identified in either the attending neuropathologist or neuropathology trainee groups for either the neurosurgical or neuromuscular case cohorts.

Conclusions.—

Our study demonstrates that accuracy of neuropathologic diagnoses and interpretation of ancillary preparations via WSI are not inferior to those generated via traditional microscopy. This study provides a framework for rapid subspecialty validation and deployment of WSI for diagnostic purposes during a pandemic event.
The Inverse Sushila Distribution: Properties and Application
Authors: Adetunji A. A. , Ademuyiwa J. A. , Adejumo O. A.
Published: June 2020

In this paper, a new lifetime distribution called the Inverse Sushila Distribution (ISD) is proposed. Its fundamental properties like the density function, distribution function, hazard rate function, survival function, cumulative hazard rate function, order statistics, moments, moments generating function, maximum likelihood estimation, quantiles function, Rényi entropy and stochastic ordering are obtained. The distribution offers more flexibility in modelling upside-down bathtub lifetime data. The proposed model is applied to a lifetime data and its performance is compared with some other related distributions.
Teaching "Climate Change and Glaciers" Using ESA-Eduspace Material
Authors: Karatza Athina , Galani Lia , Parcharidis Issaak
Published: June 2020

According to the literature, satellite imagery has positive effects on the teaching of Geography. Some of the most prominent benefits to students are the development of geographic thinking, the holistic understanding of the world, and the recognition of the problems the active citizen of the future will encounter. The present study forms part of a broader postgraduate work focusing on Satellite Imagery in Education.

Aims: The research undertaken for the present study aimed to determine the appropriateness for the Greek school system of a case study (i.e. theoretical background and worksheet exercises) presented through the European Space Agency’s (ESA) website, Eduspace.

Study Design:  Quasi-experimental.

Place and Duration of Study: National and Kapodistrian University of Athens, between December 2016 and May 2017.

Methodology: The case study entitled “Climate change and glaciers” was implemented to 19 Greek lower secondary students (control group) as approached by ESA. The purpose was to determine its positive aspects as well as points that could be further improved. Based on the findings of the implementation, researchers modified the case study proposing qualitative changes to adapt it to the Greek lower secondary school. The modified case study was applied to 20 Greek lower secondary students (experimental group).

Results: Results indicated there were differences in the educational outcomes of the two groups and, more specifically, in the degree of students' understanding of the theoretical framework and the corresponding exercises, as well as their understanding of glaciers as systems influenced by many factors.

Conclusion: Modifications can be made to the ESA case study “Climate change and glaciers” in order for it to be effective and useful in Greek lower secondary school.
Associação da postura craniocervical com disfunção temporomandibular e oclusão dentária
Authors: Lopes Paulo Raimundo Rosário , Martins Gabriela Botelho , De Araújo Roberto Paulo Correia
Published: June 2020

Não há um consenso na literatura quanto à associação entre postura craniocervical (PCC), disfunção temporomandibular (DTM) e oclusão dentária. Ainda assim, admite-se que a articulação temporomandibular está intimamente envolvida com a biomecânica cervical e cintura escapular. Objetivo: Traçar o perfil das associações entre PCC, DTM e oclusão dentária. Método: Estudo observacional em corte transversal realizado em universitários, de ambos os sexos, com idade entre 18 e 40 anos. Os voluntários foram avaliados pelo RDC/TMD, biofotogrametria, sendo esta realizada através do Software de Avaliação Postural (SAPO) pelos ângulos A1(tragus-horizontal), A2 (tragus-C7-horizontal), A3 (tragus- acrômio-vertical) e distância toraco cervical, além da análise quanto ao tipo de oclusão dentária. O tratamento dos dados foi feito a partir de medidas de tendência central, razão de prevalência e análise de correspondência múltipla assimétrica. Resultados: Foram avaliados 88 voluntários com mediana da idade de 22 anos, sendo 27 do sexo masculino e 62 do feminino. A amostra foi dividida em quatro grupos, de acordo com a presença de DTM, padrão de dor à palpação, cefaléia, PCC e oclusão. As maiores associações observadas foram: DTM tipo II com a distoclusão tipo dois, DTM tipo I com flexão de cabeça e retificação da coluna cervical; mesioclusão com alinhamento da coluna cervical e indivíduos sem dor com anteriorização da cabeça e distoclusão tipo um. Conclusão: Este estudo demonstrou que a DTM não interfere na postura da cabeça, mas que a má oclusão pode alterar a postura craniocervical nos planos sagital e frontal além de aumentar a lordose cervical.
Attentional bias toward negative and positive pictorial stimuli and its relationship with distorted cognitions, empathy, and moral reasoning among men with intellectual disabilities who have committed crimes
Authors: Sadek Susan A. , Daniel Matthew R. , Langdon Peter E.
Published: June 2020

The aims of this study were to examine: (a) whether men with intellectual disabilities who have a history of criminal offending attend to affective pictorial stimuli in a biased manner, and (b) whether there is a relationship between an affective attentional bias and offense‐supportive cognitions, empathy, and moral reasoning. Forty‐six men with intellectual disabilities who had a documented history of criminal offending, and 51 men who also had intellectual disabilities, but no such history, were recruited and asked to complete a computer‐based dot‐probe task using affective pictorial stimuli with randomization, along with measures of distorted cognitions, empathy, and moral reasoning. Those with a history of criminal offending endorsed significantly more offense‐supportive cognitions, had significantly lower general empathy, and more “mature” moral reasoning, as well as a significant attentional bias toward affective pictorial stimuli. Attentional bias significantly predicted offense‐supportive cognitions, and vice versa, having controlled for offense history, and Full‐Scale IQ, but this was not the case for empathy or moral reasoning. While the findings require replication, interventions that aim to modify attention bias with this population should be tested.
Characterization and verification of lead thickness of commercially available lead foil tape for the measurements of lead equivalency of radio‐protective shields
Authors: Lin Pei‐Jan Paul , Aljabal Areej Fawzi , Wargo Richard Ryan
Published: June 2020

Purpose

Radiation protective apparatus is normally specified in "millimeter" of lead equivalence. Typically, it is less than 0.5 mmPb with the exception of lead eyeglasses, which may be 0.75 mmPb equivalent. Upon discovery of commercially available lead foil tape, manufactured by 3M™ "Lead Foil Tape 421" (LFT) which is designed for industrial utility applications. We set out to determine if this LFT can, indeed, be employed as the reference lead in the evaluation of lead equivalency of various protective apparatus.

Method

The LFT is cut to appropriate size (50 mm × 50 mm) and stacked for varying the total lead thickness for the transmission measurements. The transmission curves are obtained following the geometry spelled out in ASTM Designation F3094‐14 standards. The radiation beam qualities corresponding to modern cardiovascular angiography equipment in the range of 60~120 kVp, in increments of 10 kVp, and in combination with the spectral shaping filters of 0, 0.1, 0.2, 0.3, 0.6 and 0.9 mmCu were employed for characterization of the lead foil tape. The transmission data of lead pieces with known thicknesses (1/64", 1/32" and 3/64") are superimposed on the lead foil tape transmission curves to validate that the 3M™ LFT is indeed usable as 0.1 mm lead.

Results

The transmission ratio (data points) of lead pieces with known thicknesses at various radiation beam qualities mentioned above, fall right onto the transmission curves of 3M™ LFT with better than 2% accuracy. Therefore, it is indeed behaving like 0.1 mm thick lead sheet, based on the superimposed transmission curves. The 3M™ "Lead Foil Tape 421" is employed as the reference lead for evaluation of radiation protective apparatus at this institution. Verification of lead protective apparatus with unknown lead equivalence can now be determined with a high accuracy and certainty.
Carcinomas with Occult Metastasis Potential: Diagnosis/Prognosis Accuracy Improvement by Means of Force Spectroscopy
Authors: Amiri Anahid , Hastert Florian D. , Dietz Christian
Published: June 2020

Accurate diagnosis of cancer stage is inevitable for the following prognosis in patients struggling with these lesions to promote their health and survival rate. Previous studies on survival rate statistics show, in some cases, failure in cancer stage surveys in which metastasis or recurrence of the disease was not accurately prognosed. Morphology study of cancer cells advances the understanding about cancer behavior and its progression, in which, in our previous study on invasive cancer cells, fewer formations of cytoskeleton components compared to their counterparts was observed. Here it is shown that carcinomas with an occult propensity of metastasis depict a number of poorly differentiated cells with decreased amounts of cytoskeleton components in a near‐well differentiated population. Force spectroscopy in conjunction with fluorescence microscopy of lung cancer, liver hepatoma, and melanoma provides a general view of these cells’ architecture, leading to the conclusion that the scarce abnormal‐shaped cells with low formation of structural filaments convey the high risk of metastatic potential of the tumor. The results demonstrate that force spectroscopy complements conventional diagnostic approaches by an accurate cytoskeleton assessment and can improve the following prognosis in epithelial cancers with occult metastasis risk.
Optimization of Carbon Encapsulated Boron Doping for High‐Performance Bulk Sintered MgB2
Authors: Sai Srikanth Arvapalli , Muralidhar Miryala , Sunsanee Pinmangkorn , Jirsa Milos , Sakai Naomichi , Oka Tetsuo , Murakami Masato
Published: June 2020

Carbon has been a standard doping agent in MgB2 for long time. It, however, has also participated in a non‐uniform distribution of the constituents throughout the bulk MgB2. To address this issue, carbon encapsulated boron (CEB) was used instead of the manually added mixture of boron and carbon. The previous studies confirmed that only low concentrations of carbon in CEB were effective for synthesis of a high‐performance bulk MgB2. Here, a further step in optimization carbon content in CEB is reported. Carbon content in CEB varied as 1, 1.1, 1.35, 1.5, and 1.9 wt%. X‐ray diffraction (XRD) results depict a slight shift in peaks corresponding to a–b plane, indicating carbon substitution into the lattice. High superconducting critical current density in self‐field, such as 660, 550, and 435 kA cm−2, was observed in the samples with 1.5 wt% CEB at 10, 15, and 20 K, respectively. In addition, Jc of 75 kA cm−2 at 2 T and 20 K was observed in the 1.5 wt% CEB sample, which is thrice the value observed in the pure sample, with a minute tradeoff in Tc (around 37.5 K). Scanning electron microscope (SEM) images reveal that small particles of size ranging from 50 to 200 nm contribute to Jc improvement. Energy‐dispersive X‐ray (EDX) results show carbon uniformly distributed throughout the bulk.
Spatiotemporally Controlled Photoresponsive Hydrogels: Design and Predictive Modeling from Processing through Application
Authors: Zhu Hongyuan , Yang Haiqian , Ma Yufei , Lu Tian Jian , Xu Feng , Genin Guy M. , Lin Min
Published: June 2020

Photoresponsive hydrogels (PRHs) are soft materials whose mechanical and chemical properties can be tuned spatially and temporally with relative ease. Both photo‐crosslinkable and photodegradable hydrogels find utility in a range of biomedical applications that require tissue‐like properties or programmable responses. Progress in engineering with PRHs is facilitated by the development of theoretical tools that enable optimization of their photochemistry, polymer matrices, nanofillers, and architecture. This review brings together models and design principles that enable key applications of PRHs in tissue engineering, drug delivery, and soft robotics, and highlights ongoing challenges in both modeling and application.
Synthesizing Organo/Hydrogel Hybrids with Diverse Programmable Patterns and Ultrafast Self‐Actuating Ability via a Site‐Specific “In Situ” Transformation Strategy
Authors: Li Cong , Feng Shiyu , Li Caicong , Sui Yuan , Shen Jinghui , Huang Chongyu , Wu Yonggang , Huang Weiguo
Published: June 2020

A simple yet robust strategy called “‘in situ' transformation” is developed to prepare organo/hydro binary gels based on the aminolysis of poly(pentafluorophenyl acrylate) (pPFPA). Treated with desired hydrophilic, oleophilic alkylamines, and their mixtures, pPFPA‐based organogels can be thoroughly transformed to targeted hydrogels, organogels, and even organohydrogels with outstanding mechanical properties. Further, relying on programed aminolysis procedures, site‐specific “in situ” transformation can be realized, giving rise to organo/hydro binary gels with diverse patterns and morphologies, such as macroscopic layered organo/hydrogel with a smooth‐transitioned yet mechanically robust interface, reconfigurable microscale organo/hydrogel hybrids with a high spatial‐resolution pattern capable of reversibly transforming between 2D sheets and 3D helixes with controlled chirality in different solvents, and core–shell structured organo/hydrogel hybrids with readily adjustable core/shell dimensions, tunable internal stress, and transparency. Finally, an oscillator based on a bilayered organo/hydrogel hybrid is developed. Attributing to the synergistic effect of organogel expansion and hydrogel contraction, as well as the robust interfacial mechanical properties, this oscillator is capable of ultrafast self‐actuating through harvesting surrounding chemical and thermal energy. This work provides new design principles and highly efficient synthetic strategy for organo/hydro binary gels, and expands their potential applications in soft robotics.
Engineering the Photocatalytic Behaviors of g/C3N4‐Based Metal‐Free Materials for Degradation of a Representative Antibiotic
Authors: Deng Yanchun , Liu Jun , Huang Yanbin , Ma Mengmeng , Liu Kong , Dou Xiaomin , Wang Zhijie , Qu Shengchun , Wang Zhanguo
Published: June 2020

Graphitic carbon nitride (g/C3N4) is of promise as a highly efficient metal‐free photocatalyst, yet engineering the photocatalytic behaviours for efficiently and selectively degrading complicated molecules is still challenging. Herein, the photocatalytic behaviors of g/C3N4 are modified by tuning the energy band, optimizing the charge extraction, and decorating the cocatalyst. The combination shows a synergistic effect for boosting the photocatalytic degradation of a representative antibiotic, lincomycin, both in the degradation rate and the degree of decomposition. In comparison with the intrinsic g/C3N4, the structurally optimized photocatalyst shows a tenfold enhancement in degradation rate. Interestingly, various methods and experiments demonstrate the specific catalytic mechanisms for the multiple systems of g/C3N4‐based photocatalysts. In the degradation, the active species, including ·O2−, ·OH, and h+, have different contributions in the different photocatalysts. The intermediate, H2O2, plays an important role in the photocatalytic process, and the detailed functions and originations are clarified for the first time.
Strong Band Bowing Effects and Distinctive Optoelectronic Properties of 2H and 1T′ Phase‐Tunable MoxRe1–xS2 Alloys
Authors: Deng Qixin , Li Xiaobo , Si Huayan , Hong Jinhua , Wang Shiyao , Feng Qingliang , Hu Chen‐Xia , Wang Shanshan , Zhang Hao‐Li , Suenaga Kazu , Xu Hua
Published: June 2020

Structure and energy band engineering of 2D materials via selective doping or phase modulation provide a significant opportunity to design them for optoelectronic devices. Here, the synthesis of high‐quality MoxRe1–xS2 alloys with tunable composition and phase structure via chemical vapor deposition growth is reported, and their novel energy band structures and optoelectronic properties are explored. The phase separation and structure reconstruction, which are found to be two serious problems in the synthesis of these alloys, are successfully suppressed through tuning their growth thermodynamics. As a result, the obtained MoxRe1–xS2 alloys have uniform composition, phase structure, and crystal orientation. Together with X‐ray photoelectron spectroscopy analysis and first‐principle calculation, the Re/Mo doping‐induced Fermi level up‐shift/down‐shift, new electronic states, and “sub‐gap” formation in MoxRe1–xS2 alloys are revealed. Especially, a strong band bowing effect is discovered in the MoxRe1–xS2 alloys with structure transition between 1T′ and 2H phases. Furthermore, these alloys reveal tunable conduction behavior from n‐type to bipolar and p‐type in 1T′ phase, as well as novel “bipolar‐like” electron conduction behavior in 2H alloys. The results highlight the unique alloying effects, which do not exist in the single‐phase 2D alloys, and provide the feasibility for potential applications in building novel electronic and optoelectronic devices.
Cobalt−Iron Oxide Nanosheets for High‐Efficiency Solar‐Driven CO2−H2O Coupling Electrocatalytic Reactions
Authors: Mi Yuying , Qiu Yuan , Liu Yifan , Peng Xianyin , Hu Min , Zhao Shunzheng , Cao Huanqi , Zhuo Longchao , Li Hongyi , Ren Junqiang , Liu Xijun , Luo Jun
Published: June 2020

Solar‐driven electrochemical overall CO2 splitting (OCO2S) offers a promising route to store sustainable energy; however, its extensive implementation is hindered by the sluggish kinetics of two key reactions (i.e., CO2 reduction reaction and oxygen evolution reaction (CO2RR and OER, respectively)). Here, as dual‐functional catalysts, Co2FeO4 nanosheet arrays having high electrocatalytic activities toward CO2RR and OER are developed. When the catalyst is applied to a complete OCO2S system driven by a triple junction GaInP2/GaAs/Ge photovoltaic cell, it shows a high photocurrent density of ≈13.1 mA cm−2, corresponding to a remarkably high solar‐to‐CO efficiency of 15.5%. Density functional theory studies suggest that the Co sites in Co2FeO4 are favorable to the formation of *COOH and *O intermediates and thus account for its efficient bifunctional activities. The results will facilitate future studies for designing highly effective electrocatalysts and devices for OCO2S.
Why Cellulose‐Based Electrochemical Energy Storage Devices?
Authors: Wang Zhaohui , Lee Yong‐Hyeok , Kim Sang‐Woo , Seo Ji‐Young , Lee Sang‐Young , Nyholm Leif
Published: June 2020

Recent findings demonstrate that cellulose, a highly abundant, versatile, sustainable, and inexpensive material, can be used in the preparation of very stable and flexible electrochemical energy storage devices with high energy and power densities by using electrodes with high mass loadings, composed of conducting composites with high surface areas and thin layers of electroactive material, as well as cellulose‐based current collectors and functional separators. Close attention should, however, be paid to the properties of the cellulose (e.g., porosity, pore distribution, pore‐size distribution, and crystallinity). The manufacturing of cellulose‐based electrodes and all‐cellulose devices is also well‐suited for large‐scale production since it can be made using straightforward filtration‐based techniques or paper‐making approaches, as well as utilizing various printing techniques. Herein, the recent development and possibilities associated with the use of cellulose are discussed, regarding the manufacturing of electrochemical energy storage devices comprising electrodes with high energy and power densities and lightweight current collectors and functional separators.
Hierarchically Porous Carbon Nanofibers with Controllable Porosity Derived from Iodinated Polyvinyl Alcohol for Supercapacitors
Authors: Seok Jae Young , Song Seung A , Yang Inyeong , Woo Kyoohee , Park Seong Yeon , Park Jung Hwan , Kim Sanha , Kim Seong Su , Yang Minyang
Published: June 2020

Porous carbon nanoframeworks have attracted considerable interest for promising applications such as water purification, catalyst supports, gas adsorption, and energy storage owing to their high surface area and electrical conductivity. Traditional synthetic methods applied for porous carbon commonly involve a number of toxic organic solvents and post‐treatments, which are time‐consuming and energy inefficient. Herein, the authors report a facile synthetic method for generating atomically small pores in carbon nanofibers, with sizes varying from ≈0.55 nm to a few nanometers, using water‐soluble and cost‐effective polyvinyl alcohol (PVA) nanofibers as a precursor through the introduction of an iodine treatment. In particular, the generation mechanism of ultrafine pores during the carbonization of iodinated PVA are deeply analyzed and elucidated through meticulous investigations into their chemical/structural properties. By the suggested mechanism, the specific surface area of the generated pores is found to be extensively controlled from 100–650 m2 g−1. This phenomenon is advanced to produce well‐controlled hierarchically porous carbon nanofibers, and analyzes the corresponding electrochemical characteristics to explore the potential usage of such fibers as a supercapacitor.
Oxygen‐Defective TiNb2O7‐x Nanochains with Enlarged Lattice Spacing for High‐Rate Lithium Ion Capacitor
Authors: Zhu Wangqin , Zou Bobo , Zhang Caihong , Ng Dickon H. L. , El‐Khodary Sherif A. , Liu Xianhu , Li Guochun , Qiu Jingxia , Zhao Yan , Yang Shiliu , Lian Jiabiao , Li Huaming
Published: June 2020

Titanium niobium oxide (TiNb2O7) is considered as a promising candidate for lithium‐ion capacitors (LICs) due to its high reversible capacity, low cost, and safety. However, it is limited by ineffective ion diffusivity and low intrinsic conductivity. Herein, in situ defect engineering in TiNb2O7‐x nanochains is successfully achieved by a facile electro‐spinning technique to improve their electrochemical performance. Remarkably, the oxygen vacancies can enhance the electronic conductivity, while the enlarged lattice spacing is conducive to the Li+ insertion/extraction, consequently enhancing the electron and ion transport kinetics. Moreover, such oxygen vacancies and enlarged lattice spacing can supply more active sites for lithium storage. Consequently, the TiNb2O7‐x nanochains exhibit a remarkable specific capacity of 440 mAh g−1 at 0.1 A g−1, superior rate capability (126 mAh g−1 at a high current density of 5.0 A g−1), and cycling stability (92% retention over 2000 cycles at 1.0 A g−1). In addition, the TiNb2O7‐x‐based LIC delivers high energy/power densities of 114 Wh kg−1 and 22502.4 W kg−1 with high‐rate performance and long cycle lifespan. This work provides new insights on in situ formation of defects to enhance the electrochemical behavior for high‐rate LICs.
A Flexible Spiraling‐Metasurface as a Versatile Haptic Interface
Authors: Bilal Osama R. , Costanza Vincenzo , Israr Ali , Palermo Antonio , Celli Paolo , Lau Frances , Daraio Chiara
Published: June 2020

Haptic feedback is the most significant sensory interface following visual cues. Developing thin, flexible surfaces that function as haptic interfaces is important for augmenting virtual reality, wearable devices, robotics and prostheses. For example, adding a haptic feedback interface to prosthesis could improve their acceptance among amputees. State of the art programmable interfaces targeting the skin feel‐of‐touch through mechano‐receptors are limited by inadequate sensory feedback, cumbersome mechanisms, or narrow frequency of operation. Here, a flexible metasurface is presented as a generic haptic interface capable of producing complex tactile patterns on the human skin at wide range of frequencies. The metasurface is composed of multiple “pixels” that can locally amplify both input displacements and forces. Each of these pixels encodes various deformation patterns capable of producing different sensations on contact. The metasurface can transform a harmonic signal containing multiple frequencies into a complex preprogrammed tactile pattern. The findings, corroborated by user studies conducted on human candidates, can open new avenues for wearable and robotic interfaces.
Recent Advances in the Synthesis of Heterocycles via Reactions Involving Elemental Sulfur
Authors: Nguyen Thanh Binh
Published: June 2020

It is well known that heterocycles are among the most significant molecules for everyday life, ranging from natural products and bioactive substances to functional materials. This review will focus on the synthesis of heterocycles by reactions involving elemental sulfur published from 2017 until now.

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Cd‐Rich Alloyed CsPb1‐xCdxBr3 Perovskite Nanorods with Tunable Blue Emission and Fermi Levels Fabricated through Crystal Phase Engineering
Authors: Guo Jie , Fu Yuhao , Lu Min , Zhang Xiaoyu , Kershaw Stephen V. , Zhang Jia , Luo Shulin , Li Yanxiu , Yu William W. , Rogach Andrey L. , Zhang Lijun , Bai Xue
Published: June 2020

One‐dimensional semiconductor nanostructures have already been used for a variety of optoelectronic applications. Metal halide perovskites have emerged in recent years as promising high‐performance optoelectronic materials, but reports on 1D nanorods (NRs) of all‐inorganic halide perovskites are still scarce. This work demonstrates a synthetic strategy toward cesium‐based inorganic perovskite NRs by exploiting composition‐controlled crystal phase engineering. It is accomplished for Cd‐rich mixed‐cation CsPb1‐xCdxBr3 nanocrystals, where the initial 1D hexagonal perovskite phase drives the growth of the 1D NRs, as supported by first‐principles calculations. The band gaps of the resulting NRs are tunable by varying the Cd‐content, and the highly uniform CsPb0.08Cd0.92Br3 NRs (with an average length of 84 nm and width of 16 nm) exhibit a true blue‐color emission centered at 460 nm, with a high quantum yield of 48%. Moreover, this work also demonstrates the tunability of the Fermi levels in the films made of CsPb1‐xCdxBr3 alloyed nanocrystals, where samples with highest Cd content show an increase of the electron concentration and a related increase in the conductivity.
An Experimental Proof that Resistance‐Switching Memory Cells are not Memristors
Authors: Kim Jinsun , Pershin Yuriy V. , Yin Ming , Datta Timir , Di Ventra Massimiliano
Published: June 2020

It has been suggested that all resistive‐switching memory cells are memristors. The latter are hypothetical, ideal devices whose resistance, as originally formulated, depends only on the net charge that traverses them. Recently, an unambiguous test has been proposed to determine whether a given physical system is indeed a memristor or not. Here, such a test is experimentally applied to both in‐house fabricated Cu‐SiO2 and commercially available electrochemical metallization cells. The results unambiguously show that electrochemical metallization memory cells are not memristors. Since the particular resistance‐switching memories employed in the study share similar features with many other memory cells, the findings refute the claim that all resistance‐switching memories are memristors. They also cast doubts on the existence of ideal memristors as actual physical devices that can be fabricated experimentally. The results then lead to formulate two memristor impossibility conjectures regarding the impossibility of building a model of physical resistance‐switching memories based on the memristor model.
Unifying Charge Generation, Recombination, and Extraction in Low‐Offset Non‐Fullerene Acceptor Organic Solar Cells
Authors: Karki Akchheta , Vollbrecht Joachim , Gillett Alexander J. , Selter Philipp , Lee Jaewon , Peng Zhengxing , Schopp Nora , Dixon Alana L. , Schrock Max , Nádaždy Vojtech , Schauer Franz , Ade Harald , Chmelka Bradley F. , Bazan Guillermo C. , Friend Richard H. , Nguyen Thuc‐Quyen
Published: June 2020

Even though significant breakthroughs with over 18% power conversion efficiencies (PCEs) in polymer:non‐fullerene acceptor (NFA) bulk heterojunction organic solar cells (OSCs) have been achieved, not many studies have focused on acquiring a comprehensive understanding of the underlying mechanisms governing these systems. This is because it can be challenging to delineate device photophysics in polymer:NFA blends comprehensively, and even more complicated to trace the origins of the differences in device photophysics to the subtle differences in energetics and morphology. Here, a systematic study of a series of polymer:NFA blends is conducted to unify and correlate the cumulative effects of i) voltage losses, ii) charge generation efficiencies, iii) non‐geminate recombination and extraction dynamics, and iv) nuanced morphological differences with device performances. Most importantly, a deconvolution of the major loss processes in polymer:NFA blends and their connections to the complex BHJ morphology and energetics are established. An extension to advanced morphological techniques, such as solid‐state NMR (for atomic level insights on the local ordering and donor:acceptor ππ interactions) and resonant soft X‐ray scattering (for donor and acceptor interfacial area and domain spacings), provide detailed insights on how efficient charge generation, transport, and extraction processes can outweigh increased voltage losses to yield high PCEs.
Alpha‐Synuclein Oligomers and Neurofilament Light Chain in Spinal Fluid Differentiate Multiple System Atrophy from Lewy Body Synucleinopathies
Authors: Singer Wolfgang , Schmeichel Ann M. , Shahnawaz Mohammad , Schmelzer James D. , Boeve Bradley F. , Sletten David M. , Gehrking Tonette L. , Gehrking Jade A. , Olson Anita D. , Savica Rodolfo , Suarez Mariana D. , Soto Claudio , Low Phillip A.
Published: June 2020

Objective

To explore the role of alpha‐synuclein (αSyn) oligomers and neurofilament light chain (NFL) in cerebrospinal fluid (CSF) as markers of early multiple system atrophy (MSA) and to contrast findings with Lewy body synucleinopathies.

Methods

In a discovery cohort of well‐characterized early MSA patients (n = 24) and matched healthy controls (CON, n = 14), we utilized enzyme‐linked immunosorbent assay to measure NFL and protein misfolding cyclic amplification (PMCA) to detect αSyn oligomers in CSF. We confirmed findings in a separate prospectively enrolled cohort of patients with early MSA (n = 38), Parkinson disease (PD, n = 16), and dementia with Lewy bodies (DLB, n = 13), and CON subjects (n = 15).

Results

In the discovery cohort, NFL was markedly elevated in MSA patients, with perfect separation from CON. αSyn‐PMCA was nonreactive in all CON, whereas all MSA samples were positive. In the confirmatory cohort, NFL again perfectly separated MSA from CON, and was significantly lower in PD and DLB compared to MSA. PMCA was again nonreactive in all CON, and positive in all but 2 MSA cases. All PD and all but 2 DLB samples were also positive for αSyn aggregates but with markedly different reaction kinetics from MSA; aggregation occurred later, but maximum fluorescence was higher, allowing for perfect separation of reactive samples between MSA and Lewy body synucleinopathies.

Interpretation

NFL and αSyn oligomers in CSF faithfully differentiate early MSA not only from CON but also from Lewy body synucleinopathies. The findings support the role of these markers as diagnostic biomarkers, and have important implications for understanding pathophysiologic mechanisms underlying the synucleinopathies. ANN NEUROL 2020;88:503–512
Room‐Temperature Formation Pathway for CdTeSe Alloy Magic‐Size Clusters
Authors: Zhang Hai , Luan Chaoran , Gao Dong , Zhang Meng , Rowell Nelson , Willis Maureen , Chen Meng , Zeng Jianrong , Fan Hongsong , Huang Wen , Chen Xiaoqin , Yu Kui
Published: June 2020

Little is known about the pathway of room‐temperature formation of ternary CdTeSe magic‐size clusters (MSCs) obtained by mixing binary CdTe and CdSe induction period samples containing binary precursor compounds (PCs) of MSCs, monomers (Ms), and fragments (Fs). Also, unestablished are dispersion effects that occur when as‐mixed samples (without incubation) are placed in toluene (Tol) and octylamine (OTA) mixtures. The resulting ternary MSCs, exhibiting a sharp optical absorption peak at 399 nm, are labelled CdTeSe MSC‐399, and their PCs are referred to as CdTeSe PC‐399. When the amount of OTA is relatively small, single‐ensemble MSC‐399 evolved without either binary CdTe or CdSe MSCs. When the OTA amount is relatively large, CdTe MSC‐371 appeared initially and then disappeared, while single‐ensemble MSC‐399 developed more deliberately. The larger the OTA amount, the more slowly these changes proceeded. The substitution reaction of CdTe PC + CdSe M/F↔CdTeSe PC‐399 + CdTe M/F is proposed to be rate‐determining for the MSC‐399 formation in a Tol and OTA mixture. This study provides further understanding of the transformation pathway between MSCs.
Organic‐Free Synthesis of Zeolite Y with High Si/Al Ratios: Combined Strategy of In Situ Hydroxyl Radical Assistance and Post‐Synthesis Treatment
Authors: Wang Jianyu , Liu Pusheng , Boronat Mercedes , Ferri Pau , Xu Zhaoguo , Liu Peng , Shen Baojian , Wang Zhendong , Yu Jihong
Published: June 2020

Zeolite Y, with a high SiO2/Al2O3 ratio (SAR), plays an important role in fluidized catalytic cracking processes. However, in situ synthesis of zeolite Y with high SARs remains a challenge because of kinetic limitations. Here, zeolite Y with an SAR of 6.35 is synthesized by a hydroxyl radical assisted route. Density‐functional theory (DFT) calculations suggest that hydroxyl radicals preferentially enhanced the formation of Si‐O‐Si bonds, thus leading to an increased SAR. To further increase the SAR, a dealumination process was carried out using citric acid, with a subsequent second‐step hydrothermal crystallization, giving an SAR of up to 7.5 while maintaining good crystallinity and high product yield. The resultant zeolite Y shows good performance in cumene cracking. Introduced here is a new strategy for synthesizing high SAR zeolite Y, which is widely used in commercial applications.
Optimizing Charge Switching in Membrane Lytic Peptides for Endosomal Release of Biomacromolecules
Authors: Sakamoto Kentarou , Akishiba Misao , Iwata Takahiro , Murata Kazuya , Mizuno Seiya , Kawano Kenichi , Imanishi Miki , Sugiyama Fumihiro , Futaki Shiroh
Published: June 2020

Endocytic pathways are practical routes for the intracellular delivery of biomacromolecules. Along with this, effective strategies for endosomal cargo release into the cytosol are desired to achieve successful delivery. Focusing on compositional differences between the cell and endosomal membranes and the pH decrease within endosomes, we designed the lipid‐sensitive and pH‐responsive endosome‐lytic peptide HAad. This peptide contains aminoadipic acid (Aad) residues, which serve as a safety catch for preferential permeabilization of endosomal membranes over cell membranes, and His‐to‐Ala substitutions enhance the endosomolytic activity. The ability of HAad to destabilize endosomal membranes was supported by model studies using large unilamellar vesicles (LUVs) and by increased intracellular delivery of biomacromolecules (including antibodies) into live cells. Cerebral ventricle injection of Cre recombinase with HAad led to Cre/loxP recombination in a mouse model, thus demonstrating potential applicability of HAad in vivo.
Frequency domain subspace identification of fractional order systems using time domain data with outliers
Authors: Li Zongyang , Wei Yiheng , Wang Jiachang , Deng Yongting , Wang Jianli , Wang Yong
Published: June 2020

This paper focuses on the identification of the multiple‐input multiple‐output commensurate fractional order systems. Different from the assumption of known frequency domain data and prior information about noise in the general frequency domain identification algorithm, the reliable frequency domain data is measured in this paper by designing special excitation signals. Then, in order to suppress the impact of noise, the data used in algorithm are truncated from the low frequency band. In addition, this paper considers the case where the sampling data are disturbed by outliers, and a matrix decomposition method with threshold value is developed to eliminate the influence of outliers. After that, the parameters of the system to be identified are estimated by the frequency domain subspace identification method. The validity of the proposed method is demonstrated by an illustrative numerical example.
Detection and characterization of stellar magnetic activity with Gaia
Authors: Distefano Elisa , Lanzafame Alessandro
Published: June 2020

The Gaia Data Release 2 (DR2) supplied a catalog of 147,644 late‐type stars for which the analysis of the G‐band photometric time series allowed the detection of the rotation period and an estimate of the magnetic activity level. The Gaia DR3 will be based on photometric time series spanning a longer time interval and will allow the detection and characterization of about 1 million stars with magnetic activity. In the present work, we show how the Gaia data allows us to study variability phenomena connected to the stellar magnetic activity and occurs on very different timescales. We also show how the Gaia data, combined with long‐term photometric surveys such as all sky automated survey (ASAS), can be exploited to detect magnetic activity cycles.
Measurements of visual binaries with EMCCD cameras and the Nice 76‐cm refractor in 2009–2010
Authors: Gili René , Prieur Jean‐Louis , Rivet Jean‐Pierre , Scardia Marco , Pansecchi Luigi , Argyle Robert W. , Ling Josefina F. , Piccotti Luca , Aristidi Eric , Koechlin Laurent , Bonneau Daniel , Maccarini Luca
Published: June 2020

We present relative astrometric and photometric measurements of visual binaries made in 2009–2010 with the 76‐cm refractor of Côte d'Azur Observatory and a pair of sensitive EMCCD ANDOR cameras. Our observing list includes optical pairs and binaries whose orbital motion is still uncertain. Three different techniques were used for obtaining measurements: Lucky Imaging, Speckle Interferometry, and the Direct Vector Autocorrelation method. From our 2,050 observations of double stars, we obtained 1,652 new measurements of the relative position of 1,792 objects, with angular separations in the range 0".1–14".1. The average accuracy is estimated at 0".02 for the angular separations and 0°.6 for the position angles. We managed to observe faint systems (mV ≈ 12) with a large magnitude difference (up to ΔmV ≈ 5). We have thus been able to measure many systems containing red dwarf stars that had been poorly monitored since their discovery. We also measured the difference of magnitude of the two components of 1,143 objects with an estimated error of 0.2
mag.
Revitalizing the sugarcane industry by adding value to A‐molasses in biorefineries
Authors: Dogbe Eunice S. , Mandegari Mohsen , Görgens Johann F.
Published: June 2020

The downward trend of global sugar market prices, as well as rising energy prices, threaten the survival of the South African sugar industry. Operating a single‐stage sugar crystallization process, which produces less crystalline sugar along with sucrose‐rich A‐molasses as a by‐product, to which value can be added in an integrated biorefinery, could be a viable solution for the industry. It would offer a diversification option as opposed to the current three‐stage crystallization process designed to achieve maximum sugar recovery. This study presents a rigorous Aspen Plus simulation development and economic assessment of different biorefinery scenarios producing succinic acid (SA) and short‐chain fructooligosaccharides (scFOS) from A‐molasses at target market sizes of 440 kt/year and 160 kt/year, respectively, considering the production capacity and market price interplays. In all, seven scenarios of single‐ or multi‐product(s) biorefinery annexed to an existing sugar mill were developed and assessed. Due to the integration benefits, all scenarios studied delivered an internal rate of return (IRR) between 24.1–61.1%, significantly above the required discount rate of 9.7%. In particular, co‐production of SA and scFOS syrup at production rates 40.5 kt/year and 13.5 kt/year from 70% and 30% of the A‐molasses, respectively resulted in the IRR of 56.1% and was considered the most attractive scenario based on the diverse bio‐production, economic performance and easy market entry of the products determined by low minimum selling prices. The proposed integration can lead to the sustainable operation of existing sugar mills by utilizing resources more efficiently, employment of product diversification and job creation. © 2020 Society of Chemical Industry and John Wiley & Sons, Ltd
Determination of levofloxacin, ciprofloxacin, moxifloxacin and gemifloxacin in urine and plasma by HPLC–FLD–DAD using pentafluorophenyl core–shell column: Application to drug monitoring
Authors: Yıldırım Sercan , Karakoç Hanife Nur , Yaşar Ahmet , Köksal İftihar
Published: June 2020

Concentrations of fluoroquinolones, which are used in the treatment of many bacterial infections, should be monitored in biological fluids as they exhibit concentration‐dependent bactericidal activity. In this study, a liquid chromatography method for the determination of levofloxacin, ciprofloxacin, moxifloxacin and gemifloxacin in human urine and plasma was developed for the first time. The efficiency of five different columns for the separation of these fluoroquinolones was compared. Experimental parameters that affect the separation, such as percentage of organic solvent, pH, temperature, gradient shape and detector wavelength, were optimized by a step‐by‐step approach. Using a pentafluorophenyl core–shell column (100 × 4.6 mm, 2.7 μm), the separation of four analytes was accomplished in <7.5 min. The developed method was validated for the determination of analytes in both urine and plasma with respect to sensitivity, specificity, linearity (r ≥ 0.9989), recovery (79.46–102.69%), accuracy, precision and stability (85.79–111.07%). The intra‐ and inter‐day accuracies were within 89.55–111.94% with relative standard deviations of 0.35–8.05%. The feasibility of method was demonstrated by analyzing urine and plasma samples of patients orally receiving levofloxacin, ciprofloxacin or moxifloxacin. The developed method is suitable for therapeutic drug monitoring of these fluoroquinolones and can be applied to pharmacokinetic and toxicological studies.
Long noncoding RNA FOXD2‐AS1 aggravates hepatocellular carcinoma tumorigenesis by regulating the miR‐206/MAP3K1 axis
Authors: Hu Wei , Feng Hui , Xu Xiaoyu , Huang Xin , Huang Xingyue , Chen Wenwei , Hao Lidan , Xia Wenfang
Published: June 2020

LncRNAs play crucial roles in the development of various cancers including hepatocellular carcinoma (HCC). Nevertheless, the function of the long noncoding RNA (lncRNA) FOXD2‐AS1 in HCC is still poorly understood. In this study, we focused on the role of FOXD2‐AS1 in HCC. We found that FOXD2‐AS1 was significantly upregulated in HCC cells in comparison to normal human liver cells, LO2. In this study, we also demonstrated that miR‐206 expression was greatly reduced in HCC cells. Furthermore, the inhibition of FOXD2‐AS1 repressed HCC cell proliferation, enhanced cell apoptosis, and restrained cell invasion and migration. The knockdown of FOXD2‐AS1 elevated miR‐206 expression, and we validated an interaction between these RNAs. Additionally, miR‐206 mimics inhibited HCC development while miR‐206 mimics had the opposite effect. MAP kinase 1 (MAP3K1) was predicted to be a target of miR‐206. We discovered that FOXD2‐AS1 modulated MAP3K1 expression by sponging miR‐206 in MHCC‐97L and HepG2 cells. Finally, our in vivo experiments validated that the knockdown of FOXD2‐AS1 inhibited HCC progression by modulating the miR‐206/MAP3K1 axis. In conclusion, this work implies FOXD2‐AS1 accelerates HCC progression through sponging miR‐206 and regulating MAP3K1 expression.
A case of Recurrent Guillain‐Barre Syndrome observed by the same clinician 12 years apart
Authors: Imam Kamran , Liu Antonio
Published: June 2020

Recurrent GBS is a rare neurological condition in which patients develop similar symptoms of motor weakness after different preceding infections and suffer shorter intervals in between subsequent episodes of GBS. However, the majority of RGBS patients undergo full recovery.