bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nucleic Acid Delivery from Granular Hydrogels
Authors: Kurt Evan , Segura Tatiana 
Published: November 2021

AbstractNucleic acid delivery has applications ranging from tissue engineering to vaccine development to infectious disease. Cationic polymer condensed nucleic acids are used with surface‐coated porous scaffolds and are able to promote long‐term gene expression. However, due to surface loading of the scaffold, there is a limit to the amount of nucleic acid that can be loaded, resulting in decreasing expression rate over time. In addition, surface‐coated scaffolds are generally non‐injectable. Here, it is demonstrated that cationic polymer condensed nucleic acids can be effectively loaded into injectable granular hydrogel scaffolds by stabilizing the condensed nucleic acid into a lyophilized powder, loading the powder into a bulk hydrogel, and then fragmenting the loaded hydrogel. The resulting hydrogel microparticles contain non‐aggregated nucleic acid particles, can be annealed post‐injection to result in an injectable microporous hydrogel, and can effectively deliver nucleic acids to embedded cells with a constant expression rate. Due to the nature of granular hydrogels, it is demonstrated that mixtures of loaded and unloaded particles and spatially resolved gene expression can be easily achieved. The ability to express genes long term from an injectable porous hydrogel will further open the applications of nucleic acid delivery.
Shape‐Changing Particles: From Materials Design and Mechanisms to Implementation
Authors: Tanjeem Nabila , Minnis Montana B. , Hayward Ryan C. , Shields Charles Wyatt 
Published: November 2021

AbstractDemands for next‐generation soft and responsive materials have sparked recent interest in the development of shape‐changing particles and particle assemblies. Over the last two decades, a variety of mechanisms that drive shape change have been explored and integrated into particulate systems. Through a combination of top‐down fabrication and bottom‐up synthesis techniques, shape‐morphing capabilities extend from the microscale to the nanoscale. Consequently, shape‐morphing particles are rapidly emerging in a variety of contexts, including photonics, microfluidics, microrobotics, and biomedicine. Herein, the key mechanisms and materials that facilitate shape changes of microscale and nanoscale particles are discussed. Recent progress in the applications made possible by these particles is summarized, and perspectives on their promise and key open challenges in the field are discussed.
Biomimetic Trachea Engineering via a Modular Ring Strategy Based on Bone‐Marrow Stem Cells and Atelocollagen for Use in Extensive Tracheal Reconstruction
Authors: Xu Yong , Dai Jie , Zhu Xinsheng , Cao Runfeng , Song Nan , Liu Ming , Liu Xiaogang , Zhu Junjie , Pan Feng , Qin Linlin , Jiang Gening , Wang Haifeng , Yang Yang 
Published: November 2021

AbstractThe fabrication of biomimetic tracheas with a architecture of cartilaginous rings alternately interspersed between vascularized fibrous tissue (CRVFT) has the potential to perfectly recapitulate the normal tracheal structure and function. Herein, the development of a customized chondroitin‐sulfate‐incorporating type‐II atelocollagen (COL II/CS) scaffold with excellent chondrogenic capacity and a type‐I atelocollagen (COL I) scaffold to facilitate the formation of vascularized fibrous tissue is described. An efficient modular ring strategy is then adopted to develop a CRVFT‐based biomimetic trachea. The in vitro engineering of cartilaginous rings is achieved via the recellularization of ring‐shaped COL II/CS scaffolds using bone marrow stem cells as a mimetic for native cartilaginous ring tissue. A CRVFT‐based trachea with biomimetic mechanical properties, composed of bionic biochemical components, is additionally successfully generated in vivo via the alternating stacking of cartilaginous rings and ring‐shaped COL I scaffolds on a silicone pipe. The resultant biomimetic trachea with pedicled muscular flaps is used for extensive tracheal reconstruction and exhibits satisfactory therapeutic outcomes with structural and functional properties similar to those of native trachea. This is the first study to utilize stem cells for long‐segmental tracheal cartilaginous regeneration and this represents a promising method for extensive tracheal reconstruction.
Highly Efficient Self‐Healing Multifunctional Dressing with Antibacterial Activity for Sutureless Wound Closure and Infected Wound Monitoring
Authors: Tang Ning , Zhang Rongjun , Zheng Youbin , Wang Jing , Khatib Muhammad , Jiang Xue , Zhou Cheng , Omar Rawan , Saliba Walaa , Wu Weiwei , Yuan Miaomiao , Cui Daxiang , Haick Hossam 
Published: November 2021

AbstractWound healing represents a major clinical and public healthcare problem that is frequently challenged by infection risks, detrimental consequences on the surrounding tissues, and difficulties to monitor the healing process. Here we report on a novel self‐healing, antibacterial, and multifunctional wound dressing for sutureless wound closure and real‐time monitoring of the healing parameters. The self‐healing elastomer contains cetyltrimethylammonium bromide (CTAB) and has high mechanical toughness (35 MJ m−3), biocompatibility, and outstanding antibacterial activity (bactericidal rate is ≈90% in 12 h), enabling the wound dressing to effectively inhibit bacterial growth and accelerate infected wound healing. In vivo tests based on full‐thickness skin incision model shows that the multifunctional wound dressing can help in contracting wound edges and facilitate wound closure and healing, as could be evidenced by notably dense and well‐organized collagen deposition. The test provides an evidence that the integrated sensor array within the multifunctional wound dressing can monitor temperature, pH, and glucose level of the wound area in real‐time, providing reliable and timely information of the condition of the wound. Ultimately, the reported multifunctional dressing would be of high value in managing the burden associated with wound healing via personalised monitoring and treatment approaches, digital and other people‐centred solutions for health care.
The Road for 2D Semiconductors in the Silicon Age
Authors: Wang Shuiyuan , Liu Xiaoxian , Zhou Peng 
Published: November 2021

AbstractContinued reduction in transistor size can improve the performance of silicon integrated circuits (ICs). However, as Moore's law approaches physical limits, high‐performance growth in silicon ICs becomes unsustainable, due to challenges of scaling, energy efficiency, and memory limitations. The ultrathin layers, diverse band structures, unique electronic properties, and silicon‐compatible processes of 2D materials create the potential to consistently drive advanced performance in ICs. Here, the potential of fusing 2D materials with silicon ICs to minimize the challenges in silicon ICs, and to create technologies beyond the von Neumann architecture, is presented, and the killer applications for 2D materials in logic and memory devices to ease scaling, energy efficiency bottlenecks, and memory dilemmas encountered in silicon ICs are discussed. The fusion of 2D materials allows the creation of all‐in‐one perception, memory, and computation technologies beyond the von Neumann architecture to enhance system efficiency and remove computing power bottlenecks. Progress on the 2D ICs demonstration is summarized, as well as the technical hurdles it faces in terms of wafer‐scale heterostructure growth, transfer, and compatible integration with silicon ICs. Finally, the promising pathways and obstacles to the technological advances in ICs due to the integration of 2D materials with silicon are presented.
Manipulating Electroluminochromism Behavior of Viologen‐Substituted Iridium(III) Complexes through Ligand Engineering for Information Display and Encryption
Authors: Wang Xuecheng , Kuang Jianru , Wu Pengcheng , Zong Zheng , Li Zixian , Wang Hao , Li Jinlu , Dai Peiling , Zhang Kenneth Yin , Liu Shujuan , Huang Wei , Zhao Qiang 
Published: November 2021

AbstractElectrically controlling photoluminescence has attracted great research interest and offers many opportunities for technological developments. Electroluminochromic materials undergo redox reactions under low‐voltage stimuli to achieve reversible luminescence switching. Till now, photoluminescence switching of a single molecule caused by electrical stimuli is restricted to intensity response because the redox‐active moieties are good electron donors or acceptors and electrical stimuli can regulate the photoinduced electron‐transfer and affect the luminescence intensity. In this work, the manipulation of the electroluminochromism behavior of a series of viologen‐substituted iridium(III) complexes through the regulation of ligand orbital energy levels and electronic communication between the viologen pendants and the iridium(III) complex core is reported. Electrochemical redox reactions reversibly modulate either the luminescence quenching effect or the push–pull electronic effect of the viologen substituents, achieving multicolor “on–off” luminescence response toward electrical stimuli and luminescence manipulation between two emissive states with different wavelengths and lifetimes. To illustrate the promising applications of these electroluminochromic materials, recording and displaying luminescence information under electrical stimuli are demonstrated. Information encryption is realized by letting the electroluminochromism occur in the near‐infrared region or in the time domain. Near‐infrared camera or time‐resolved luminescence analysis can be used to help read the invisible information.
Nanostructure Control in 3D Printed Materials
Authors: Bobrin Valentin A. , Lee Kenny , Zhang Jin , Corrigan Nathaniel , Boyer Cyrille 
Published: November 2021

AbstractCurrently, there are no straightforward methods to 3D print materials with nanoscale control over morphological and functional properties. Here, a novel approach for the fabrication of materials with controlled nanoscale morphologies using a rapid and commercially available Digital Light Processing 3D printing technique is demonstrated. This process exploits reversible deactivation radical polymerization to control the in‐situ‐polymerization‐induced microphase separation of 3D printing resins, which provides materials with complex architectures controllable from the macro‐ to nanoscale, resulting in the preparation of materials with enhanced mechanical properties. This method does not require specialized equipment or process conditions and thus represents an important development in the production of advanced materials via additive manufacturing.
Recent Advances on MXene‐Based Electrocatalysts toward Oxygen Reduction Reaction: A Focused Review
Authors: Peera Shaik Gouse , Liu Chao , Sahu Akhila Kumar , Selvaraj Manickam , Rao M. C. , Lee Tae Gwan , Koutavarapu Ravindranadh , Shim Jaesool , Singh Lakhveer 
Published: November 2021

AbstractMXenes are novel transition‐metal‐carbide‐ and/or nitride‐based 2D materials that attract considerable attention in the field of energy storage and conversion because of their unique layered structures, electronic properties, and surface chemistries, which facilitate various electrochemical reactions. MXenes have been rarely investigated as probable catalysts or catalyst supports for the oxygen reduction reaction (ORR). In this review, recent developments in experimental and theoretical research on MXene‐based electrocatalysts for the ORR are examined. MXenes are known to have tremendous potential as stable supports for various Pt and non‐Pt metals for electrocatalytic ORR processes. Theoretical analyses have determined several potential MXene candidates for applications as supports for Pt and non‐Pt metal nanoparticles; experimental studies have shown that Pt‐ and non‐Pt‐deposited MXenes exhibit appreciable ORR activity and stability in alkaline media, followed by acidic media. However, experimental studies also indicate several limitations and challenges that must be addressed for efficient application of MXenes as supports for the ORR. Therefore, current research on MXenes with respect to the ORR is discussed, with a focus on synthesis strategies, ORR activities, and factors responsible for enhancing the electrocatalytic performance. Several strategies for the further development of efficient and durable ORR‐based MXene catalysts are also proposed.
Spin‐Charge Conversion in Fe/Au/Sb2Te3 Heterostructures as Probed By Spin Pumping Ferromagnetic Resonance
Authors: Longo Emanuele , Locatelli Lorenzo , Belli Matteo , Alia Mario , Kumar Arun , Longo Massimo , Fanciulli Marco , Mantovan Roberto 
Published: November 2021

AbstractLarge‐area antimony telluride (Sb2Te3) thin films are grown by a metal organic chemical vapor deposition technique on 4” Si(111) substrates, and their topological character probed by magnetoconductance measurements. When interfaced with Fe thin films, broadband ferromagnetic resonance spectroscopy (BFMR) shows a clear increase of the damping parameter in Fe/Sb2Te3 when compared to a reference Fe layer, which may suggest the occurrence of spin pumping (SP) into Sb2Te3. Simultaneously, X‐ray reflectivity and conversion electron Mossbauer spectroscopy evidence the development of a chemically and magnetically pure Fe/Sb2Te3 interface. However, by conducting SP‐FMR, it is shown that no spin‐to‐charge conversion (S2C) occurs in Fe/Sb2Te3, while a clear SP signal develops by introducing a 5 nm Au interlayer between Fe and Sb2Te3, with a measured inverse Edelstein effect conversion efficiency of λIEE = 0.27 nm. The results shed some light on the correlation among the chemical‐structural‐magnetic properties of the Fe/Sb2Te3 interface, the broadening of the magnetic damping parameter as detected by BFMR, and the occurrence of S2C, as probed by SP‐FMR.
Solution‐Processed Graphene Thin‐Film Enables Binder‐Free, Efficient Loading of Nanocatalysts for Electrochemical Water Splitting
Authors: Cho Yun Seong , Rhee Dongjoon , Kim Hee Jun , Kim Hyun Seung , Baik Jeong Min , Kang Joohoon 
Published: November 2021

AbstractElectrochemical water splitting is promising to produce high purity hydrogen that can serve as clean and renewable energy. Reducing the size of catalysts down to the nanometer regime is critical for enhancing the electrochemical performance because reactions mostly occur at the surface of materials. However, fully exploiting the advantage of small nanocatalysts is challenging because accessible catalytic surface area is reduced by particle aggregation and the use of binders. In addition, a significant fraction of nanocatalysts is lost through the electrode pores during catalyst loading. Here, a simple strategy to efficiently load nanocatalysts without using binders is reported. By introducing a thin layer of graphene nanosheets on a porous membrane, a uniform nanocatalyst film via vacuum filtration of the dispersion can be created. The nanocatalyst/graphene composite can be transferred to a carbon paper without fracturing to function as a catalyst layer. The method is compatible with various nanomaterials to realize electrodes for hydrogen and oxygen evolution reactions and even bifunctional electrodes that exhibit activities for both. Significantly, the resulting electrodes show better performance than those produced by directly filtrating through the carbon paper. Moreover, the binder‐free surface allows for further enhancement in catalytic activity via postchemical treatments.
Hierarchically Structured Components: Design, Additive Manufacture, and Their Energy Applications
Authors: Wang Panfeng , Xuan Jin , Zhang Ronghao , Zhang Hao , Wang Qiang , Wang Haoyang , Liu Houli , Zhang Li 
Published: November 2021

AbstractPursuing high energy efficiency and reaction rate is an effective direction in mitigating the energy and climate crisis. Mass transfer intensification is a powerful approach to enhance the energy efficiency and reaction rate in the energy conversion and storage processes. The nature‐inspired channels are outstanding tools to uniformly distribute the reactants, fast remove products, and reduce the diffusion distance for mass transfer intensification in monolithic adsorbents, structured catalysts, and electrodes. Besides, hierarchical pores are also a contributor to improve the reactant diffusion rate in the matrix. Additive manufacturing, combining the design of printing material and post‐treatment, provides a promising opportunity to accurately control the channels and adjust the pores in electrodes, catalysts, and adsorbents. This review summarizes the main state‐of‐the‐art methods to design ideal channels and to control the sizes and amounts of pores for the optimum hierarchical structure design, as well as the techniques to realize the hierarchical structure by additive manufacturing. In addition, this review also communicates the recently unlocked advantages of the designable channels and hierarchical pores in applications of adsorptions, chemical reactions, and electrochemical energy storage. Lastly, a new approach to design and fabricate the hierarchical structures is proposed, along with its potential benefits.
Mode‐Center Placement of Monolayer WS2 in a Photonic Polymer Waveguide
Authors: Frank Angelina , Zhou Justin , Grieve James A. , Verzhbitskiy Ivan , Viana‐Gomes José , Loh Leyi , Schmid Michael , Watanabe Kenji , Taniguchi Takashi , Eda Goki , Ling Alexander 
Published: November 2021

AbstractThe effective integration of 2D materials such as monolayer transition metal dichalcogenides (TMDs) into photonic waveguides and integrated circuits is being intensely pursued due to these materials’ strong exciton‐based optical response. This work presents a platform where a 2D heterostructure (WS2‐hBN) is directly integrated into the photonic mode‐center of a novel polymer ridge waveguide. Finite‐difference time‐domain simulations and collection of photoluminescence from the guided mode indicate that this system exhibits significantly improved waveguide‐emitter coupling and mode confinement over a previous elastomer platform. This is facilitated by the platform's enhanced refractive‐index contrast and a new method for mode‐center integration of the coupled TMD. The integration is based on a simple dry‐transfer process that is applicable to other 2D materials, and the platform's elastomeric nature is a natural fit to explore strain‐tunable hybrid‐photonic devices. The demonstrated ability of coupling photoluminescence to a polymer waveguide opens up new possibilities for hybrid‐photonic systems in a variety of contexts.
Single and Dual Doping of Blue‐Emissive ZnSeTe Quantum Dots with Transition Metal Ions
Authors: Song Seung‐Won , Lee Sun‐Hyoung , Jo Dae‐Yeon , Yoon Suk‐Young , Kim Hyun‐Min , Kim Yuri , Han Jee‐Na , Lee Young‐Ju , Do Young Rag , Yang Heesun 
Published: November 2021

AbstractDoping particularly with transition metal ions is an effectual means to modulate photoluminescence (PL) of quantum dots (QDs). The precedent doped QDs rely primarily on single doping with either Cu+ or Mn2+ into the most common host compositions of (Zn)CdS, ZnSe, and InP, with little success on co‐doping with both impurities enabling their simultaneous emissions. Herein, single and dual doping are explored with Cu+ and/or Mn2+ into blue‐emissive ZnSeTe QDs. PL of the singly doped ZnSeTe QDs synthesized via a co‐nucleation process, comprising host and dopant emissions, is spectrally tuned by varying the concentration of each dopant. For the effective dual doping toward co‐emergence of both dopant‐related emissions, a two‐step doping strategy, where co‐nucleation doping of Mn2+ is temporally decoupled from diffusion doping of Cu+, is devised. In the resulting co‐doped ZnSeTe QDs, successfully showing three distinct emission components, the relative spectral distribution of triple emissions is readily modulated by individually adjusting Cu and Mn concentrations, producing color‐quality tunable white emissions. Upon elaborate multishelling, the co‐doped QDs display outstanding PL quantum yields of 72–75%. Singly and dually doped QDs are further applied for the fabrication of QD light‐emitting diodes, and their electroluminescence is examined compared to PL.
Asymmetric Dieckmann Condensation towards Spirocyclic Oxindoles Catalyzed by Amino Acid‐Derived Phosphonium Salts
Authors: Yu Longhui , Liu Jun , Wang Hongyu , Xu Lijun , Wu Yufei , Zheng Changwu , Zhao Gang 
Published: November 2021

AbstractAn asymmetric Dieckmann condensation towards spirocyclic oxindoles and aza‐oxindoles catalyzed by amino acid‐derived phosphonium salt has been developed, which expanded the applicability of asymmetric phosphonium salt catalysis in the production of 1,3‐dicarbonyl compounds. This reaction is distinguished by its mild conditions (−20 °C), low catalyst loading (3–5 mol%), and broad substrate scope (25 examples). Control experiments revealed that both the catalyst‘s phosphonium skeleton and H‐bonding site were required. Product transformations and a gram scale experiment were also carried out.magnified image
Rhodium(III)‐Catalyzed Direct C7‐Selective Alkenylation and Alkylation of Indoles with Maleimides
Authors: Sheng Yaoguang , Gao Yi , Duan Bingbing , Lv Mengxia , Chen Yao , Yang Mengjie , Zhou Jianmin , Liang Guang , Song Zengqiang 
Published: November 2021

AbstractA versatile and efficient method for the coupling of maleimides and indoles at the C7‐position has been established under Rh(III) catalysis. The present protocol was compatible with various functional groups, diverse 3‐(indol‐7‐yl)maleimides and 3‐(indol‐7‐yl)succinimides were obtained in moderate to excellent yields by switching reaction conditions. Moreover, this method further highlights the unique practical application for the conjugation with pharmaceutically useful compounds and amino acid derivatives. To explore the mechanism of this transformation, deuteration studies and control experiments have been carried out.magnified image
Pyrrolidine‐Catalyzed Annulations of Quinone Monoacetals with Naphthols: Synthesis of 2‐Oxabicyclo[3.3.1]nonane Skeletons, Transformations and Reaction Mechanism
Authors: Li Xiaojie , Xiao Tianyu , He Guangke , Zhu Shugao , Zhu Dunru , Shen Ruwei 
Published: November 2021

AbstractHerein, we report the pyrrolidine‐catalyzed annulation reaction of p‐quinone monoacetals with naphthols at room temperature. The reaction is also extended to including 4‐hydroxycoumarin, 4‐hydroxy‐1‐methylcarbostyril, 4‐hydroxycarbostyril, and several β‐ketoesters as the nucleophiles, thereby providing a collection of bridged cyclic compounds bearing 2‐oxabicyclo[3.3.1]nonane skeletons in 41–96% yields. The reaction can be adapted to gram‐scale synthesis, and several transformations of the obtained bridged cyclic products are demonstrated for the preparation of polycyclic compounds that may find utility in related fields. Mechanism studies indicate the engagement of iminium intermediate in the reaction, and a bridged ring enamine intermediate can be observed by NMR.magnified image
Iron‐Catalyzed Alkene Trifluoromethylation in Tandem with Phenol Dearomatizing Spirocyclization: Regioselective Construction of Trifluoromethylated Spirocarbocycles
Authors: Zhao Yilin , Wang Xue , Yao Ru , Li Chengwen , Xu Zelin , Zhang Liming , Han Guifang , Hou Jingli , Liu Yangping , Song Yuguang 
Published: November 2021

AbstractIn the presence of Fe(III) complex and Bipy ligand, CF3‐containing spirocarbocycles were conveniently obtained in 20–99% yields with high regioselectivity through Iron‐catalyzed trifluoromethylation of unactivated alkenes coupled with phenol dearomatizing spirocyclization.magnified image