bluuebunny/crossref_metadata_2025 huggingface dataset:
Silver Nanotube Networks with Ultrahigh Strain Limit as Reliable Flexible Transparent Electrode and Tactile Sensor
Authors: Bu Jingyuan , Tan Dongchen , Sun Nan , Jiang Chengming , Li Qikun , Bi Sheng , Song Jinhui
Published: August 2021

Durable and extremely deformable electrodes play a significant role in the field of high‐strain flexible electronics, including wearable electronics and flexible tactile sensor. However, the existing flexible transparent electrodes hardly have a high strain limit and low square resistance simultaneously, like the combination of carbon‐based electrodes and metal electrodes. Herein, a semicovered silver nanotube (SC‐AgNT) network electrode is proposed. The SC‐AgNT network electrode consists of semicovered polymer nanofibers and a highly integrated Ag nanotube network for achieving high strain limit and low square resistance. Further, a tactile sensor based on this electrode is built, demonstrating the advance of the new electrodes. The strength enhancement layer consists of polyvinyl alcohol (PVA) nanofibers in the SC‐AgNT network electrode, making the electrode have the minimum bending radius of 0.1 mm and the maximum twist angle of 120° (0.9 Ω sq−1 at 94% transmittance). A tactile sensing interface based on the SC‐AgNT network electrode displays highly stable electrical properties under multiple types and times of comprehensive deformation and touch deformation. The technical strategy for strengthening metal network electrodes and preparing integrated low‐resistance metal networks can be extended to enhance the performance of other metal‐based flexible electrodes and flexible devices.
Diarylfluorene‐Based Organic Semiconductor Materials toward Optoelectronic Applications
Authors: Han Yamin , Bai Lubing , Lin Jinyi , Ding Xuehua , Xie Linghai , Huang Wei
Published: August 2021

Modular production is a convenient strategy that not only realizes the mass production of conjugated materials, but also precisely regulates their photoelectrical property for optoelectronic applications. Diarylfluorene is a functional building block in constructing organic semiconductors arising from its special electronic, spacial, and conformational structure. Because of easy chemical modification, tunable electronic structure, and high photoluminescence quantum yield, diarylfluorene‐based conjugated materials have undergone remarkable development in variety of low‐cost optoelectronic devices. Herein, the authors present an overview mainly to describe the recent research progresses of diarylfluorene‐based molecules, including 9,9′‐diarylfluorene, heteroatom‐containing spirocyclic diarylfluorene, and 4‐position substituted 9,9′‐diarylfluorene. The synthetic routes, molecular structures as well as their diverse applications toward optoelectronic devices are introduced and summarized systematically. Finally, the future challenges and development are also discussed in this vital research field.
Colossal Reversible Barocaloric Effects in Layered Hybrid Perovskite (C10H21NH3)2MnCl4 under Low Pressure Near Room Temperature
Authors: Li Junning , Barrio María , Dunstan David J. , Dixey Richard , Lou Xiaojie , Tamarit Josep‐Lluís , Phillips Anthony E. , Lloveras Pol
Published: August 2021

Barocaloric effects in a layered hybrid organic–inorganic compound, (C10H21NH3)2MnCl4, that are reversible and colossal under pressure changes below 0.1 GPa are reported. This barocaloric performance originates in a phase transition characterized by different features: A strong disordering of the organic chains, a very large volume change, a very large sensitivity of the transition temperature to pressure and a small hysteresis. The obtained values are unprecedented among solid‐state cooling materials at such low pressure changes and demonstrate that colossal effects can be obtained in compounds other than plastic crystals. The temperature‐pressure phase diagram displays a triple point indicating enantiotropy at high pressure.
Morphology Transformation Pathway of Block Copolymer‐Directed Cooperative Self‐Assembly of ZnO Hybrid Films Monitored In Situ during Slot‐Die Coating
Authors: Tian Ting , Yin Shanshan , Tu Suo , Weindl Christian L. , Wienhold Kerstin S. , Liang Suzhe , Schwartzkopf Matthias , Roth Stephan V. , Müller‐Buschbaum Peter
Published: August 2021

Cooperative self‐assembly (co‐assembly) of diblock copolymers (DBCs) and inorganic precursors that takes inspiration from the rich phase separation behavior of DBCs can enable the realization of a broad spectrum of functional nanostructures with the desired sizes. In a DBC assisted sol–gel chemistry approach with polystyrene‐block‐poly(ethylene oxide) and ZnO, hybrid films are formed with slot‐die coating. Pure DBC films are printed as control. In situ grazing‐incidence small‐angle X‐ray scattering measurements are performed to investigate the self‐assembly and co‐assembly process during the film formation. Combining complementary ex situ characterizations, several distinct regimes are differentiated to describe the morphological transformations from the initially solvent‐dispersed to the ultimately solidified films. The comparison of the assembly pathway evidences that the key step in the establishment of the pure DBC film is the coalescence of spherical micelles toward cylindrical domains. Due to the presence of the phase‐selective precursor, the formation of cylindrical aggregates in the solution is crucial for the structural development of the hybrid film. The pre‐existing cylinders in the ink impede the domain growth of the hybrid film during the subsequent drying process. The precursor reduces the degree of order, prevents crystallization of the PEO block, and introduces additional length scales in the hybrid films.
Nanozyme with Robust Catalase Activity by Multiple Mechanisms and Its Application for Hypoxic Tumor Treatment
Authors: Wang Chongchong , Li Yanqing , Yang Weijie , Zhou Lin , Wei Shaohua
Published: August 2021

Utilizing catalase‐mimicking nanozymes to produce O2 is an effective method to overcome tumor hypoxia. However, it is challenging to fabricate nanozymes with ultrahigh catalytic activity. Palladium nanosheet (Pd NS), a photothermal agent for photothermal therapy (PTT), has superior catalase‐mimicking activity. Here, titanium dioxide (TiO2) is used to modify Pd NS (denoted Pd@TiO2) by a simple one‐step method to improve its catalytic activity about 8 times. The enhancement mechanism's fundamental insights are discussed through experiments and density functional theory calculations. Next, zinc phthalocyanine is loaded on Pd@TiO2 to form a nanomotor (denoted PTZCs) with the synergistic activities of photodynamic therapy and PTT. PTZCs inherit the catalase activity of Pd@TiO2 to facilitate the decomposition of endogenous H2O2 to O2, which can relieve tumor hypoxia and propel PTZC migration to expand the reach of PTZCs, further enhancing its synergistic treatment outcome both in vitro and in vivo. It is proposed that this work can provide a simple and effective strategy for catalytic activity enhancement and bring a critical new perspective to studying and guiding the nanozyme design.
A Highly Compressible and Stretchable Carbon Spring for Smart Vibration and Magnetism Sensors
Authors: Gao Huai‐Ling , Wang Ze‐Yu , Cui Chen , Bao Jia‐Zheng , Zhu Yin‐Bo , Xia Jun , Wen Shao‐Meng , Wu Heng‐An , Yu Shu‐Hong
Published: August 2021

Porous carbon materials demonstrate extensive applications for their attractive characteristics. Mechanical flexibility is an essential property guaranteeing their durability. After decades of research efforts, compressive brittleness of porous carbon materials is well resolved. However, reversible stretchability remains challenging to achieve due to the intrinsically weak connections and fragile joints of the porous carbon networks. Herein, it is presented that a porous all‐carbon material achieving both elastic compressibility and stretchability at large strain from −80% to 80% can be obtained when a unique long‐range lamellar multi‐arch microstructure is introduced. Impressively, the porous all‐carbon material can maintain reliable structural robustness and durability under loading condition of cyclic compressing–stretching process, similar to a real metallic spring. The unique performance renders it as a promising platform for making smart vibration and magnetism sensors, even capable of operating at extreme temperatures. Furthermore, this study provides valuable insights for creating highly stretchable and compressible porous materials from other neat inorganic components for diverse applications in future.
Cp*Co(III)‐Catalyzed Dehydrative C2‐Prenylation of Pyrrole and Indole with Allyl Alcohols
Authors: Basuli Suchand , Sahu Samrat , Saha Shuvendu , Maji Modhu Sudan
Published: August 2021

Non‐activated allyl alcohols are utilized as allylating agent for thiocarbamate‐directed allylation of pyrrole and indole. The synthetic methodology is accompanied by advantages like silver‐free conditions and generates water as the by‐product. A wide range of substituted pyrroles and indoles along with several structurally different allyl alcohols took part in the reaction. Among notable examples, biologically relevant prenylation, geranylation, and synthesis of 1,3‐dienes are achieved. Selective mono allylation of pyrrole, gram‐scale synthesis, and ready deprotection of directing group are the other key highlights of this method.

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Mixed Triboelectric and Flexoelectric Charge Transfer at the Nanoscale
Authors: Qiao Huimin , Zhao Pin , Kwon Owoong , Sohn Ahrum , Zhuo Fangping , Lee Dong‐Min , Sun Changhyo , Seol Daehee , Lee Daesu , Kim Sang‐Woo , Kim Yunseok
Published: August 2021

The triboelectric effect is a ubiquitous phenomenon in which the surfaces of two materials are easily charged during the contact‐separation process. Despite the widespread consequences and applications, the charging mechanisms are not sufficiently understood. Here, the authors report that, in the presence of a strain gradient, the charge transfer is a result of competition between flexoelectricity and triboelectricity, which could enhance charge transfer during triboelectric measurements when the charge transfers of both effects are in the same direction. When they are in the opposite directions, the direction and amount of charge transfer could be modulated by the competition between flexoelectric and triboelectric effects, which leads to a distinctive phenomenon, that is, the charge transfer is reversed with varying forces. The subsequent results on the electrical power output signals from the triboelectrification support the proposed mechanism. Therefore, the present study emphasizes the key role of the flexoelectric effect through experimental approaches, and suggests that both the amount and direction of charge transfer can be modulated by manipulating the mixed triboelectric and flexoelectric effects. This finding may provide important information on the triboelectric effect and can be further extended to serve as a guideline for material selection during a nanopatterned device design.
Boosting Antitumor Sonodynamic Therapy Efficacy of Black Phosphorus via Covalent Functionalization
Authors: Liu Yajuan , Li Zhiyuan , Fan Feng , Zhu Xianjun , Jia Lingbo , Chen Muqing , Du Pingwu , Yang Lihua , Yang Shangfeng
Published: August 2021

Sonodynamic therapy (SDT) triggered by ultrasound represents an emerging tumor therapy approach with minimally invasive treatment featuring nontoxicity and deep tissue‐penetration, and its efficacy sensitively depends on the sonosensitizer which determines the generation of reactive oxygen species (ROS). Herein, for the first time covalently functionalized few‐layer black phosphorus nanosheets (BPNSs) are applied as novel sonosensitizers in SDT, achieving not only boosted SDT efficacy but also inhibited cytotoxicity relative to the pristine BPNSs. Three different covalently functionalized‐BPNSs are synthesized, including the first fullerene‐functionalized BPNSs with C60 covalently bonded onto the surface of BPNSs (abbreviated as C60‐s‐BP), surface‐functionalized BPNSs by benzoic acid (abbreviated as BA‐s‐BP), and edge‐functionalized BPNSs by C60 (abbreviated as C60‐e‐BP), and the role of covalent functionalization pattern of BPNSs on its SDT efficacy is systematically investigated. Except C60‐e‐BP, both surface‐functionalized BPNSs (C60‐s‐BP, BA‐s‐BP) exhibit higher SDT efficacies than the pristine BPNSs, while the highest SDT efficacy is achieved for BA‐s‐BP due to its strongest capability of generating the hydroxyl (·OH) radicals, which act as the dominant ROS to kill the tumor cells.
Unidirectional Macroscopic Alignment of Chlorobenzo[c]‐[1,2,5]thiadiazole‐Based Semiconducting Copolymers with Controlled Regiochemistry
Authors: Chung Sein , Cho Yongjoon , Kim Jinsung , Lee Seon Baek , Park Chaneui , Kim Seunghyun , Kang Boseok , Yang Changduk , Cho Kilwon
Published: August 2021

Solution‐processable donor–acceptor‐type conjugated copolymers are considered one of the most promising alternatives to inorganic semiconductors. The introduction of strong electron‐withdrawing groups in the acceptor units of the copolymers has been shown to favor fast charge transport; however, the correlation among the halogen‐substituted molecular structure, solid‐state packing, and charge transport properties is unclear. In this study, new chlorine‐atom‐substituted donor–acceptor copolymers comprising chlorobenzo[c]‐[1,2,5]thiadiazole and 4,4‐dihexadecyl‐4H‐cyclopenta[1,2‐b:5,4‐b′]dithiophene are synthesized and their physicochemical properties are compared with those of their unsubstituted or nitrogen‐incorporated backbone analogs. In addition, the regioregularity of the synthesized copolymers is controlled to investigate the effects of regiochemistry on the polymer backbone alignment using the nanogroove method. The results demonstrate that different degrees of regioregularity in the main chains induce a substantially dissimilar effect of the nanogroove and capillary force on the orientation of the polymer backbone, long‐range crystalline order, and charge transport properties of the conjugated polymers.
Temperature of Conductive Nanofilaments in Hexagonal Boron Nitride Based Memristors Showing Threshold Resistive Switching
Authors: Lanza Mario , Palumbo Felix , Shi Yuanyuan , Aguirre Fernando , Boyeras Santiago , Yuan Bin , Yalon Eilam , Moreno Enrique , Wu Tianru , Roldan Juan B.
Published: August 2021

Two‐terminal metal/insulator/metal (MIM) memristors exhibiting threshold resistive switching (RS) can develop advanced key tasks in solid‐state nano/micro‐electronic circuits, such as selectors and integrate‐and‐fire electronic neurons. MIM‐like memristors using multilayer hexagonal boron nitride (h‐BN) as dielectric are especially interesting because they have shown threshold RS with ultra‐low energy consumption per state transition down to the zeptojoule regime. However, the factors enabling stable threshold RS at such low operation energies are still not fully understood. Here it is shown that the threshold RS in 150 nm × 150 nm Au/Ag/h‐BN/Au memristors is especially stable because the temperature in the h‐BN stack during operation (i.e., at low currents ≈1 μA) is very low (i.e., ≈310 K), due to the high in‐plane thermal conductivity of h‐BN and its low thickness. Only when the device is operated at higher currents (i.e., ≈200 μA) the temperatures at the h‐BN increase remarkably (i.e., >500 K), which produce a stable non‐volatile conductive nanofilament (CNF). This work can bring new insights to understand the performance of 2D materials based RS devices, and help to develop the integration of 2D materials in high‐density nanoelectronics.
High‐Performance Ultraviolet Organic Light‐Emitting Diode Enabled by High‐Lying Reverse Intersystem Crossing
Authors: Zhang Han , Li Ganggang , Guo Xiaomin , Zhang Kai , Zhang Bing , Guo Xuecheng , Li Yuxuan , Fan Jianzhong , Wang Zhiming , Ma Dongge , Tang Ben Zhong
Published: August 2021

Ultraviolet (UV) organic emitters that can open up applications for future organic light‐emitting diodes (OLEDs) are of great value but rarely developed. Here, we report a high‐quality UV emitter with hybridized local and charge‐transfer (HLCT) excited state and its application in UV OLEDs. The UV emitter, 2BuCz‐CNCz, shows the features of low‐lying locally excited (LE) emissive state and high‐lying reverse intersystem crossing (hRISC) process, which helps to balance the color purity and exciton utilization of UV OLED. Consequently, the OLED based on 2BuCz‐CNCz exhibits not only a desired narrowband UV electroluminescent (EL) at 396 nm with satisfactory color purity (CIEx, y=0.161, 0.031), but also a record‐high maximum external quantum efficiency (EQE) of 10.79 % with small efficiency roll‐off. The state‐of‐the‐art device performance can inspire the design of UV emitters, and pave a way for the further development of high‐performance UV OLEDs.
Activity Trends and Mechanisms in Peroxymonosulfate‐Assisted Catalytic Production of Singlet Oxygen over Atomic Metal‐N‐C Catalysts
Authors: Gao Yun , Wu Tongwei , Yang Chengdong , Ma Chao , Zhao Zhenyang , Wu Zihe , Cao Sujiao , Geng Wei , Wang Yi , Yao Yongyi , Zhang Yanning , Cheng Chong
Published: August 2021

We synthesized a series of carbon‐supported atomic metal‐N‐C catalysts (M‐SACs: M=Mn, Fe, Co, Ni, Cu) with similar structural and physicochemical properties to uncover their catalytic activity trends and mechanisms. The peroxymonosulfate (PMS) catalytic activity trends are Fe‐SAC>Co‐SAC>Mn‐SAC>Ni‐SAC>Cu‐SAC, and Fe‐SAC displays the best single‐site kinetic value (1.65×105 min−1 mol−1) compared to the other metal‐N‐C species. First‐principles calculations indicate that the most reasonable reaction pathway for 1O2 production is PMS→OH*→O*→1O2; M‐SACs that exhibit moderate and near‐average Gibbs free energies in each reaction step have a better catalytic activity, which is the key for the outstanding performance of Fe‐SACs. This study gives the atomic‐scale understanding of fundamental catalytic trends and mechanisms of PMS‐assisted reactive oxygen species production via M‐SACs, thus providing guidance for developing M‐SACs for catalytic organic pollutant degradation.
Interdisciplinary Reflections on Conversation Analysis, Power, and Open Dialogue
Authors: Ong Ben
Published: August 2021

As a psychologist and family therapist my professional education has had a significant impact on my personal life and how I see the world. Over the past four years I have been privileged enough to work on a PhD, which has again changed my perspective. This research examines Open Dialogue sessions using conversation analysis, which focuses on normative conversational structures and how they are utilised to achieve social actions. Conversation analysis forced me to abandon previous therapeutic concepts and look at Open Dialogue and family therapy generally from an interdisciplinary perspective. Through this process I have noticed a few recurring ideas: interactions are sequential, psychotherapy involves abstraction, and power is unavoidable and not inherently ‘bad.’ In this article, I elaborate on these ideas in the first person and how they have changed the way I practice and think about family therapy with reference to the appropriate research and literature.
Multimode process monitoring using adaptive auto‐associative kernel regression
Authors: Shen Feifeng , Xu Chen , Yang Huizhong
Published: August 2021

Complex modern industrial processes often exhibit multimodal characteristic because of different manufacturing strategies. Although the conventional auto‐associative kernel regression (AAKR) method is suitable for monitoring the nonlinear multimodal processes, different high Pearson correlations between variables from different modes reduce the fault detection accuracy of AAKR model. Moreover, within‐mode process data usually present the property of serial correlation, resulting in the auto‐correlation and cross‐correlation of variables simultaneously existing in the dynamic processes. In order to reduce the influence of correlation and improve the accuracy of fault detection based on AAKR, a novel multimode process monitoring method combining zero‐phase component analysis (ZCA) as a data preprocessing technique and traditional AAKR is proposed. To further enhance the detectability of the model to small disturbance, a modified statistic based on multivariate exponentially weighted moving average (MEWMA) is studied in this paper. The monitoring performance of the proposed approach is evaluated through a numerical example, the Tennessee Eastman (TE) process and the real Bisphenol‐A (BPA) production process.
Extremely high reinforcement of high‐density polyethylene by low loading of unzipped multi‐wall carbon nanotubes
Authors: Yang Di , Qi Xiaohua , Zhang Wenna , Yang Na , Chen Mengyao , Wang Yao , Huang Linjun , Wang Jiuxing , Wang Shicao , Strizhak Peter , Tang Jianguo
Published: August 2021

Multi‐wall carbon nanotubes (MWCNTs) are excellent potential reinforcements for composites due to their high‐mechanical properties. However, a high concentration of MWCNTs is required to reach a good reinforcement. The present study is aimed to show that using unzipped MWCNTs (uMWCNTs) results in an extraordinary enhancement of the mechanical properties of high‐density polyethylene (HDPE). Using 0.2% wt/wt of uMWCNTs as a filler increases the tensile strength and Young's modulus of HDPE by more than 100%. Transmission electron microscopy (TEM), X‐ray diffraction, Raman, Fourier transform infrared spectroscopy, X‐ray photoelectron spectroscopy (XPS), and differential scanning calorimeter (DSC) studies show that the structure and functionality of uMWCNTs and HDPE matrix preserve for their composites. The enhancement in the mechanical properties is mainly associated with an interfacial interaction between separate uMWCNTs sheets and HDPE matrix resulting in increasing the degree of crystallinity and decreasing the crystallite size. Our study provides a new way to fabricate high‐performance composite materials with a low concentration of carbon nanostructures.
Recyclable Pd‐based polysaccharide catalyst for aerobic oxidation of benzyl alcohol
Authors: Wolfson Adi , Stamker Eliraz , Levy‐Ontman Oshrat
Published: August 2021

Palladium acetate that was heterogenized together with triphenylphosphine trisulfonate ligand on renewable polysaccharides was employed in the aerobic oxidation of benzyl alcohol in three representative solvents—hexane, ethyl acetate, and ethanol. Solvent polarity was found to affect the reaction rate, as both the solubility of benzyl alcohol and oxygen depend on the nature of the solvent. The conversion rate was decreased in the order of hexane > ethanol > ethyl acetate (conversion rates in the presence of the heterogenized iota‐based catalyst after 24 h of reaction were 38, 20, and 15%, respectively). In addition, the nature of the polysaccharide, that is, the type and numbers of functional groups on its backbone, also affected the reaction rate, where xanthan gum yielded the highest conversion rate of 58% in hexane. Finally, though hexane was found to be the preferred solvent for the heterogeneous system, catalytic performance in hexane decreased during recycling while in ethanol it increased due to the formation of palladium nanoparticles. To reveal the structural changes undergone by the catalyst during the reaction, several techniques were used, including energy dispersive X‐ray spectrometry‐scanning electronic microscopy, X‐ray photoelectron spectroscopy, Transition electronic microscopy, and thermal gravimetric analysis. This simple and straightforward heterogenization procedure can be also used for immobilization of different other metal complexes in variety of organic reactions.
Synthesis and performance of a novel polycarboxylate superplasticizer through grafting the β‐cyclodextrin on the side chain by click reaction
Authors: Li Bin , Gao Ruijun , Wang Ling
Published: August 2021

A novel monovinyl β‐cyclodextrin monomer (β‐P) is employed to synthesize polycarboxylate superplasticizers with β‐cyclodextrin (β‐CD) grafted on the end of side chain [PAA‐g‐(β‐P)nHPEG, n is the mass ratio of β‐P in macromonomer, n = 3% ~ 9%]. β‐P is synthesized through grafting β‐CD on the polyoxyethylene (PEO) via click reaction, which is the first try to superimpose the steric hindrance effect of PEO and β‐CD during the preparation of polycarboxylate superplasticizer. FTIR, 1H NMR, GPC, and DLS are used to characterize the molecular structure of the intermediates and the products. Compared with PAA‐g‐HPEG (PCE0) only with PEO as side chains, cement paste containing PAA‐g‐(β‐P)7%HPEG has the largest fluidity; PAA‐g‐(β‐P)9%HPEG corresponds to the best fluidity retention performance; cement paste containing PAA‐g‐(β‐P)nHPEG has shorter setting time. The DLS results reveal that the introduction of β‐CD in PAA‐g‐(β‐P)nHPEG extends the side chain length and increases the steric hindrance effect. The adsorption test results show that the novel PCE has good slump retention performance because it is adsorbed on cement particles less but more lives in the liquid phase with the n increasing. This study provides a new approach to synthesize high‐performance polycarboxylate superplasticizer.
Electrospun cellulose fibers from ionic liquid: Practical implications toward robust morphology
Authors: Ciuzas Darius , Krugly Edvinas , Sriubaite Simona , Pauliukaityte Ingrida , Baniukaitiene Odeta , Bulota Mindaugas , Martuzevicius Dainius
Published: August 2021

Fibrous matrix of cellulose was obtained by wet‐type electrospinning of cellulose in ionic liquid, 1‐butyl‐3‐methylimidazolium acetate (BMIMAc). The experiments were designed to determine the effects of electric field intensity and the amount of dissolved cellulose on cellulose fiber morphology and diameter. Taking to account practical implications, that is, fiber size and the effectiveness of production, the most effective production of fibers took place using 3% cellulose/BMIMAc solution at electric field of 4.8 kV cm−1, feed rate of 2.38 ml h−1. Analysis has shown that cellulose was fully dissolved and consisted purely of regenerated cellulose (type II), while having porosity of 90% and average fiber width of 1.95 ± 0.9 μm. The scanning electron microscopy and micro‐computed tomography analyses revealed a robust structural integrity of the formed fibrous matrix, which featured an area density of 85 ± 8 g/m2. The mechanical properties (strength of 12.03 ± 1.1 MPa; strain at break 2.6 ± 0.3%) indicate that in this study strong fibrous cellulose matrix was formed which could be used for the production of biocomposites or as biocompatible scaffolds.
Rhodium(III)‐Catalyzed Sequential C−H Activation and Cyclization from N‐Methoxyarylamides and 3‐Diazooxindoles for the Synthesis of Isochromenoindolones
Authors: Ko Gi Hoon , Maeng Chanyoung , Jeong Haneal , Han Sang Hoon , Han Gi Uk , Lee Kyungsup , Noh Hee Chan , Lee Phil Ho
Published: August 2021

An efficient synthetic method for structurally various isochromenoindolones has been demonstrated through Rh(III)‐catalyzed C−H activation followed by a cyclization reaction of N‐methoxyarylamides with 3‐diazooxindoles. The sequential reaction involves the streamlined formation of C−C and C−O bonds in one pot. The present method provides a broad range of isochromenoindolones as a new privileged scaffold in moderate to good yields with the release of methoxyamine and molecular nitrogen and has the benefits of a broad substrate scope and good functional group tolerance.
Optimal synchronization control for heterogeneous multi‐agent systems: Online adaptive learning solutions
Authors: Zhou Yuanqiang , Li Dewei , Gao Furong
Published: August 2021

This paper presents an online adaptive learning solution to the optimal synchronization control problem of heterogeneous multi‐agent systems via a novel distributed policy iteration approach. For the leader‐follower multi‐agents, the dynamics of all the followers are heterogeneous with leader disturbance. To make the output of each follower synchronize with the leader's output, we propose a synchronization control protocol where the stability conditions for selecting the feedback gains are given. Next, with a minimization of the output tracking errors, we optimize the feedback gains for the synchronization control protocol, and the unique solutions for those feedback gains are learned via a novel distributed policy iteration approach. We prove that the proposed online adaptive learning solution will converge to the optimal control solution under some mild conditions. Finally, an illustrative numerical example is provided to show the effectiveness of the approach.
Optimization of muscle cell culture media using nonlinear design of experiments
Authors: Cosenza Zachary , Block David E , Baar Keith
Published: August 2021

Optimizing media for biological processes, such as those used in tissue engineering and cultivated meat production, is difficult due to the extensive experimentation required, number of media components, nonlinear and interactive responses, and the number of conflicting design objectives. Here we demonstrate the capacity of a nonlinear design‐of‐experiments (DOE) method to predict optimal media conditions in fewer experiments than a traditional DOE. The approach is based on a hybridization of a coordinate search for local optimization with dynamically adjusted search spaces and a global search method utilizing a truncated genetic algorithm using radial basis functions to store and model prior knowledge. Using this method, we were able to reduce the cost of muscle cell proliferation media while maintaining cell growth 48 h after seeding using 30 common components of typical commercial growth medium in fewer experiments than a traditional DOE (70 vs. 103). While we clearly demonstrated that the experimental optimization algorithm significantly outperforms conventional DOE, due to the choice of a 48 h growth assay weighted by medium cost as an objective function, these findings were limited to performance at a single passage, and did not generalize to growth over multiple passages. This underscores the importance of choosing objective functions that align well with process goals.
EBV‐positive B‐cell lymphomas and lymphoproliferative disorders: Review from the perspective of immune escape and immunodeficiency
Authors: Satou Akira , Nakamura Shigeo
Published: August 2021

Background

Epstein‐Barr virus (EBV) is detected in a variety of B‐cell lymphomas (BCLs) and B‐cell lymphoproliferative disorders (B‐LPDs). Immunodeficiency has been considered to play a key role in the pathogenesis of these diseases. In addition, immune escape of tumor cells may also contribute to the development of EBV+ BCLs and B‐LPDs. The PD‐1/PD‐L1 pathway is particularly important for immune escape of tumor cells that contribute to development of lymphoma through suppression of cytotoxic T‐cell function. We now consider PD‐L1 immunohistochemistry (IHC) a very useful method for predicting whether tumor cells of lymphoid malignancies are characterized by the immune escape mechanism.

Methods

We reviewed articles of EBV+ BCLs and B‐LPDs from the perspective of immune escape and immunodeficiency, particularly focusing on PD‐L1 IHC.

Results

Based on PD‐L1 IHC, we consider that EBV+ BCL and B‐LPD can be classified into three types: “immunodeficiency”, “immune escape”, and “immunodeficiency + immune escape” type. The immunodeficiency type includes EBV+ diffuse large BCL (DLBCL) of the elderly, EBV+ sporadic Burkitt lymphoma, EBV+ mucocutaneous ulcer, and methotrexate (MTX)‐associated B‐LPD. The immune escape type includes EBV+ classic Hodgkin lymphoma (CHL) and EBV+ DLBCL of the young. The immunodeficiency + immune escape type includes CHL type MTX‐associated LPD and a minor subset of EBV+ DLBCL of the elderly.

Conclusions

Recently, good results have been reported for immune check‐point inhibitors in treating lymphoma. Lymphomas and LPDs characterized by immune escape are regarded as good candidates for PD1/PD‐L1 blockade therapy. Therefore, from both the clinical and pathological perspective, we suggest that lymphoma diagnosis should be made considering immune escape and immunodeficiency.
Phytochemical Constituents and Biological Activities of Plants from the GenusCissampelos
Authors: He Jingtao , Li Fangyi , Yan Xiaohui , Cheng Qian , Xue Rongtao , Yu Heshui , Li Zheng , Wang Chunhua
Published: August 2021

Cissampelosis a significant genus comprising of approximately 21 species of the medicinal plants (Menispermaceae). The plants of this genus are used in traditional medicine for the treatment of various ailments such as asthma, arthritis, dysentery, hyperglycemia, cardiopathy, hypertension and other related problems. These plants are rich in bioactive dibenzylisoquinoline and aborphine as well as small amounts of other ingredients. In recent years, the chemical constituents and pharmacological activities ofCissampelosgenus have been paid more and more attention due to their diversity. Herein, we compile the chemical constituents and biological activities on this genus, and summarize the13C‐NMR data of the main bioactive ingredients. All information comes from scientific databases such as Google Scholar, PubMed, Sci‐Finder, ScienceDirect, Web of Science and CNKI. It provides valuable data for the future research and development ofCissampelosgenus.
Anthocyanins from Pomegranate (Punica granatum L.) and Their Role in Antioxidant Capacities in Vitro
Authors: Zhao Xueqing , Yuan Zhaohe
Published: August 2021

As phytochemicals, anthocyanins are not only responsible for the diverse colors in nature, but are associated with broad‐spectrum health‐promoting effects for human beings. Pomegranate is abundant in anthocyanins which possess high antioxidant capacities. However, the pomegranate anthocyanins profile and their contributions to antioxidant capacities are not fully depicted. The purpose of this article is to review anthocyanins from pomegranate as important antioxidants. Total anthocyanin content (TAC) and six major components vary greatly with intrinsic and extrinsic factors. In pomegranate, anthocyanins mainly acted as primary antioxidants, while their action as secondary antioxidants were not conclusive. The antioxidant potentials of anthocyanins were significantly affected by factors especially chemical structure and detection assays in vitro. The current knowledge may provide insights into potential applications for pomegranate anthocyanins based on their antioxidant activities.
Inhibition Profiles of Some Symmetric Sulfamides Derived from Phenethylamines on Human Carbonic Anhydrase I, and II Isoenzymes
Authors: Topal Fevzi , Aksu Kadir , Gulcin Ilhami , Tümer Ferhan , Goksu Süleyman
Published: August 2021

In this work, the inhibitory effect of some symmetric sulfamides derived from phenethylamines were determined against human carbonic anhydrase (hCA) I, and II isoenzymes, and compared with standard compound acetazolamide. IC50 values were obtained from the Enzyme activity (%)‐[Symmetric sulfamides] graphs. Also, Ki values were calculated from the Lineweaver‐Burk graphs. Some symmetric sulfamides compounds (11–18) demonstrated excellent inhibition effects against hCA I, and II isoenzymes. These compounds demonstrated effective inhibitory profiles with IC50 values in ranging from 21.66–28.88 nM against hCA I, 14.44–30.13 nM against hCA II. Among these compounds, the best Ki value for hCA I (Ki: 8.34±1.60 nM) and hCA II (Ki: 16.40±1.00 nM) is compound number 11. Besides, the IC50 value of acetazolamide used as a standard was determined as hCA I, hCA II 57.75 nM, 49.50 nM, respectively. Moreover, in silico ADME‐Tox study showed that all synthesized compounds (11–18) had good oral bioavailability in light of Jorgensen's rule of three, and of Lipinski's rule of five.
Development of Tyrphostin Analogues to Study Inhibition of the Mycobacterium tuberculosis Pup Proteasome System**
Authors: Janssen Guido V. , Zhang Susan , Merkx Remco , Schiesswohl Christa , Chatterjee Champak , Darwin K. Heran , Geurink Paul P. , van der Heden van Noort Gerbrand J. , Ovaa Huib
Published: August 2021

Tuberculosis is a global health problem caused by infection with the Mycobacterium tuberculosis (Mtb) bacteria. Although antibiotic treatment has dramatically reduced the impact of tuberculosis on the population, the existence and spreading of drug resistant strains urgently demands the development of new drugs that target Mtb in a different manner than currently used antibiotics. The prokaryotic ubiquitin‐like protein (Pup) proteasome system is an attractive target for new drug development as it is unique to Mtb and related bacterial genera. Using a Pup‐based fluorogenic substrate, we screened for inhibitors of Dop, the Mtb depupylating protease, and identified I‐OMe‐Tyrphostin AG538 (1) and Tyrphostin AG538 (2). The hits were validated and determined to be fast‐reversible, non‐ATP competitive inhibitors. We synthesized >25 analogs of 1 and 2 and show that several of the synthesized compounds also inhibit the depupylation actions of Dop on native substrate, FabD‐Pup. Importantly, the pupylation activity of PafA, the sole Pup ligase in Mtb, was also inhibited by some of these compounds.
Effect of eliminating pre‐discharge transthoracic echocardiogram on outcomes after TAVR
Authors: Welle Garrett A. , El‐Sabawi Bassim , Thaden Jeremy J. , Greason Kevin L. , Klarich Kyle W. , Nkomo Vuyisile T. , Alkhouli Mohamad A. , Guerrero Mayra E. , Crestanello Juan A. , Gulati Rajiv , Rihal Charanjit S. , Eleid Mackram F.
Published: August 2021

Objectives

The aim of this study was to determine the safety of eliminating the pre‐discharge transthoracic echocardiogram (TTE) on 30‐day outcomes in patients undergoing transcatheter aortic valve replacement (TAVR).

Background

TTE is utilized before, during, and after TAVR. Post‐procedural, pre‐discharge TTE assists in assessment of prosthesis function and detection of clinically significant paravalvular leak (PVL) after TAVR.

Methods

Patients who underwent TAVR at Mayo Clinic from July 2018 to July 2019 were included in a prospective institutional registry. Patients undergoing TAVR prior to February 2019 received a pre‐discharge TTE, while those undergoing TAVR after February 2019 did not. Both cohorts were evaluated with TTE at 30 days post‐TAVR.

Results

A total of 330 consecutive patients were included. Of these, 160 patients (age 81.1 ± 7.6) had routine pre‐discharge TTE, while 170 patients (age 78.9 ± 7.5) were dismissed without routine pre‐discharge TTE. Mortality at 30 days was similar between the two groups (0% and 1.2%, respectively). One episode of PVL requiring intervention (0.6%) occurred in the pre‐discharge TTE group and none in the group without pre‐discharge TTE at 30‐day follow‐up. There was a similar incidence of total composite primary and secondary adverse events between the cohort receiving a pre‐discharge TTE and those without (28.1% vs. 25.3%, P = 0.56) at 30 days. The most common event was need for permanent pacemaker or ICD implantation in both groups (13.1% vs. 11.8%, P = 0.71).

Conclusions

Elimination of the pre‐discharge TTE is safe and associated with comparable 30‐day outcomes to routine pre‐discharge TTE. These findings have implication for TAVR practice cost‐efficiency and health care utilization.
Hybrid ZnSe‐SnSe2 Nanoparticles Embedded in N‐doped Carbon Nanocube Heterostructures with Enhanced and Ultra‐stable Lithium‐Storage Performance
Authors: Yu Litao , Kim Kyung Su , Saeed Ghuzanfar , Kang Jun , Kim Kwang Ho
Published: August 2021

Bimetallic selenide composites with multiple valence transitions and high theoretical capacities have attracted great attention as lithium‐ion‐battery anodes, but their rapid capacity fading and scarce research limit their development. Herein, novel hybrid ZnSe‐SnSe2 nanoparticles embedded in N‐doped carbon nanocubes (ZSS⊂NCNs) are synthesized by a facile nucleation assembly, carbon coating, and in situ selenation route. The obtained uniform ZSS⊂NCN materials exhibit high surface area, N‐doping carbon shell, extra inner void space, and excellent resilient mechanism nanostructure, which provide amounts of active sites, outstanding electrochemical kinetics, and buffer the volume expansion in the conversion and alloy/dealloy processes. For lithium‐ion‐battery half‐cells, the uniform ZSS⊂NCN materials display a high initial coulombic efficiency of 81.9 %, an increased capacity of 846.6 mA h g−1 at 0.2 A g−1 after 100 cycles, and an excellent rate capability (414.1 mA h g−1 at 5 A g−1). When assembled with a LiMn2O4 cathode, the ZSS⊂NCNs//LiMn2O4 full cells also present excellent electrochemical properties. Ex situ XRD analyses at different potentials in the lithiation/delithiation processes confirm a polymorphic phase transformation in the ZSS⊂NCNs. The synthesized ZSS⊂NCN enriched bimetallic selenide composites and the facile synthesis route provide a strategy for other bimetallic selenides, sulfide or phosphide composites with stable nanostructure to be utilized in energy storage.
Recognition of 1‐phenylethylamine enantiomers by thin solid films of inherently chiral calix[4]arene
Authors: Kazantseva Zoya I. , Koshets Igor A. , Trybrat Oleksandr O. , Yesypenko Oleksandr A. , Kalchenko Vitali I.
Published: August 2021

The enantiodiscrimination properties of stereomerically pure inherently chiral calix[4]arene acetic acids, as well as their esters and amides in relation to 1‐phenylethylamine stereoisomers in liquid and gaseous phases were studied by means of proton magnetic resonance spectroscopy (1H NMR) and quartz crystal microbalance (QCM) techniques. Series of QCM sensors with thin films of inherently chiral calix[4]arenes, immobilized on the quartz resonator surfaces by spin‐coating and spreading drop methods have been fabricated. It was shown that sensors based on calix[4]arene acetic acids are able to recognize R‐ and S‐forms of 1‐phenylethylamine in gaseous phase under concentration level of 10–400 ppm.
Photoinduced FeCl3‐Catalyzed Alkyl Aromatics Oxidation toward Degradation of Polystyrene at Room Temperature†
Authors: Zhang Guoxiang , Zhang Zongnan , Zeng Rong
Published: August 2021

Main observation and conclusion

While polystyrene is widely used in daily life as a synthetic plastic, the subsequently selective degradation is still very challenging and highly required. Herein, we disclose a highly practical and selective reaction for the catalytically efficient oxidation of alkyl aromatics (including 1°, 2°, and 3° alkyl aromatics) to carboxylic acids. While dioxygen was used as the sole terminal oxidant, this protocol was catalyzed by the inexpensive and readily available ferric compound (FeCl3) with irradiation of visible light (blue LEDs) under only 1 atmosphere of O2 at room temperature. This system could further facilitate the selective degradation of polystyrene to benzoic acid, providing an important and practical tool to generate high‐value chemical from abundant polystyrene wastes.
Phase Behaviors of Multi‐tailed B2AB2‐Type Regio‐isomeric Giant Surfactants at the Columnar‐Spherical Boundary†
Authors: Shao Yu , Han Di , Yan Xiaojin , Hou Bo , Li Yiwen , He Jinlin , Fu Qiang , Zhang Wen‐Bin
Published: August 2021

Main observation and conclusion

We report herein the precision synthesis and phase behaviors of multi‐tailed B2AB2‐type regio‐isomeric giant surfactants consisting of a hydrophilic polyhedral oligomeric silsesquioxane (POSS) head tethered with four hydrophobic polystyrene (PS) tails. The synthesis was accomplished through two sequential “click” reactions to give a series of regio‐isomeric giant surfactants S2DS2 (where S is short for PS tails and D for hydroxyl‐functionalized POSS) in para‐, meta‐, and ortho‐configurations. Their phase structures and phase behaviors at the columnar‐spherical boundary were investigated with a single PS tail molecular weight of 1.4 kDa. Specifically, the para‐ and meta‐isomers show hexagonally packed cylinders phases with slightly different order‐disorder transition temperatures (~120 °C and ~130 °C) and the ortho‐isomer exhibits an order‐order transition from a kinetically favored, metastable dodecagonal quasi‐crystal phase to a thermodynamically stable sigma phase at ~120 °C, as well as a further transition into the disordered state at ~140 °C. The phase diagram was constructed and their differences were rationalized based on the calculated interfacial area per molecule. This work demonstrates that tiny structural disparity could not only lead to unconventional phase formation in single‐component macromolecules, but also render dynamic and rich phase behaviors in these macromolecular assemblies.
Evaluating two land surface models for Brazil using a full carbon cycle benchmark with uncertainties
Authors: Caen Auguste , Smallman T. Luke , de Castro Aline Anderson , Robertson Eddy , von Randow Celso , Cardoso Manoel , Williams Mathew
Published: August 2021

Forecasts of tropical ecosystem C cycling diverge among models due to differences in simulation of internal processes such as turnover, or transit times, of carbon pools. Estimates of these processes for the recent past are needed to test model representations, and so build confidence in model forecasts within and across biomes. Here, we evaluate carbon cycle process representation in two land surface models [Joint UK Land Environment Simulator (JULES) and Integrated Model of Land Surface Processes (INLAND)] for the period 2001–10 across Brazilian biomes. Model outputs are evaluated using the ILAMB system. Probabilistic benchmarking data were created using the carbon data model framework that assimilates observational times series of leaf area index and maps of woody biomass and soil C. New custom uncertainty metrics assess if models are within benchmark uncertainties. Simulations are better in homogeneous areas of vegetation type, and are less robust at ecotones between biomes, likely due to disturbance effects and parameter errors. Gross biosphere‐atmosphere fluxes are robustly modelled across Brazil. However, benchmark uncertainty is too high on net ecosystem exchange to provide an accurate evaluation of the models. The LSMs have significant differences in internal carbon allocation and the dynamics of the different C pools. JULES models dead C stocks more accurately while living C stocks are best resolved for INLAND. JULES' over‐estimate of the C wood pool results from over‐estimation of both inputs to wood and the transit time of wood. INLAND's under‐estimate of dead C stocks arises from an under‐estimate of the transit time of dead organic matter. The models are better at simulating annual averages than seasonal variation of fluxes. Analyses of monthly net C exchanges show that INLAND correctly simulates seasonality, but over‐estimates amplitudes, whereas JULES correctly simulates the annual amplitudes, but is out of phase with the benchmark.
A fast and accurate threat detection and prevention architecture using stream processing
Authors: Lobato Antonio G. Pastana , Andreoni Lopez Martin , Cardenas Alvaro A. , Duarte Otto Carlos M. B. , Pujolle Guy
Published: August 2021

Late detection of security breaches increases the risk of irreparable damages and limits any mitigation attempts. We propose a fast and accurate threat detection and prevention architecture that combines the advantages of real‐time streaming with batch processing over a historical database. We create a dataset by capturing both legitimate and malicious traffic and propose two ways of combining packets into flows, one considering a time window and the other analyzing the first few packets of each flow per period. We also investigate the effectiveness of our proposal on real‐world network traces obtained from a significant Brazilian network operator providing broadband Internet to their customers. We implement and evaluate three classification algorithms and two anomaly detection methods. The results show an accuracy higher than 95% and an excellent trade‐off between attack detection and false‐positive rates. We further propose an improved scheme based on software defined networks that automatically prevents threats by analyzing only the first few packets of a flow. The proposal promptly and efficiently blocks threats, is robust, and can scale up, even when the attacker employs spoofed IP.