bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mechanoreceptor‐Inspired Dynamic Mechanical Stimuli Perception based on Switchable Ionic Polarization
Authors: Yoon Hong‐Joon , Lee Dong‐Min , Kim Young‐Jun , Jeon Sera , Jung Jae‐Hwan , Kwak Sung Soo , Kim Jihye , Kim SeongMin , Kim Yunseok , Kim Sang‐Woo 
Published: March 2021

AbstractDiverse touch experiences offer a path toward greater human–machine interaction, which is essential for the development of haptic technology. Recent advances in triboelectricity‐based touch sensors provide great advantages in terms of cost, simplicity of design, and use of a broader range of materials. Since performance solely relies on the level of contact electrification between materials, triboelectricity‐based touch sensors cannot effectively be used to measure the extent of deformation of materials under a given mechanical force. Here, an ion‐doped gelatin hydrogel (IGH)‐based touch sensor is reported to identify not only contact with an object but also deformation under a certain level of force. Switchable ionic polarization of the gelatin hydrogel is found to be instrumental in allowing for different sensing mechanisms when it is contacted and deformed. The results show that ionic polarization relies on conductivity of the hydrogels. Quantitative studies using voltage sweeps demonstrate that higher ion mobility and shorter Debye length serve to improve the performance of the mechanical stimuli‐perceptible sensor. It is successfully demonstrated that this sensor offers dynamic deformation‐responsive signals that can be used to control the motion of a miniature car. This study broadens the potential applications for ionic hydrogel‐based sensors in a human–machine communication system.
Excited State Energy Transfer in Metal‐Organic Frameworks
Authors: Wang Zhiye , Wang Cheng 
Published: March 2021

AbstractExcited state energy transfer in metal‐organic frameworks (MOFs) is of great interest due to potential application of these materials in photocatalysis and fluorescence sensing. In photocatalysis, a light‐harvesting antenna of MOFs can collect energy from a much larger area than a single reaction center and efficiently transport the energy to the active site to enhance photocatalytic efficiency, mimicking nature photosynthesis. In fluorescence sensing, excited state traveling on the framework can search for analyte quencher molecules to give amplified fluorescence quenching, so that one quencher turns off multiple excited states to enhance signal. Key to these designer performances is highly efficient energy transfer on these framework materials that are determined by types of excited states, dimension of the materials, and structure of the frameworks. Advancement of MOF synthetic chemistry provides new tools to control the rate and directionality of energy transfer in these materials, opening opportunities in manipulating excited states at an unprecedented level.
Mechanoluminescence Rebrightening the Prospects of Stress Sensing: A Review
Authors: Zhuang Yixi , Xie Rong‐Jun 
Published: March 2021

AbstractThe emergence of new applications, such as in artificial intelligence, the internet of things, and biotechnology, has driven the evolution of stress sensing technology. For these emerging applications, stretchability, remoteness, stress distribution, a multimodal nature, and biocompatibility are important performance characteristics of stress sensors. Mechanoluminescence (ML)‐based stress sensing has attracted widespread attention because of its characteristics of remoteness and having a distributed response to mechanical stimuli as well as its great potential for stretchability, biocompatibility, and self‐powering. In the past few decades, great progress has been made in the discovery of ML materials, analysis of mechanisms, design of devices, and exploration of applications. One can find that with this progress, the focus of ML research has shifted from the phenomenon in the earliest stage to materials and recently toward devices. At the present stage, while showing great prospects for advanced stress sensing applications, ML‐based sensing still faces major challenges in material optimization, device design, and system integration.
Interactive Materials for Bidirectional Redox‐Based Communication
Authors: Li Jinyang , Wang Sally P. , Zong Guanghui , Kim Eunkyoung , Tsao Chen‐Yu , VanArsdale Eric , Wang Lai‐Xi , Bentley William E. , Payne Gregory F. 
Published: March 2021

AbstractEmerging research indicates that biology routinely uses diffusible redox‐active molecules to mediate communication that can span biological systems (e.g., nervous and immune) and even kingdoms (e.g., a microbiome and its plant/animal host). This redox modality also provides new opportunities to create interactive materials that can communicate with living systems. Here, it is reported that the fabrication of a redox‐active hydrogel film can autonomously synthesize a H2O2 signaling molecule for communication with a bacterial population. Specifically, a catechol‐conjugated/crosslinked 4‐armed thiolated poly(ethylene glycol) hydrogel film is electrochemically fabricated in which the added catechol moieties confer redox activity: the film can accept electrons from biological reductants (e.g., ascorbate) and donate electrons to O2 to generate H2O2. Electron‐transfer from an Escherichia coli culture poises this film to generate the H2O2 signaling molecule that can induce bacterial gene expression from a redox‐responsive operon. Overall, this work demonstrates that catecholic materials can participate in redox‐based interactions that elicit specific biological responses, and also suggests the possibility that natural phenolics may be a ubiquitous biological example of interactive materials.
Touch‐Based Stressless Cortisol Sensing
Authors: Tang Wanxin , Yin Lu , Sempionatto Juliane R. , Moon Jong‐Min , Teymourian Hazhir , Wang Joseph 
Published: March 2021

AbstractTracking fluctuations of the cortisol level is important in understanding the body's endocrine response to stress stimuli. Traditional cortisol sensing relies on centralized laboratory settings, while wearable cortisol sensors are limited to slow and complex assays. Here, a touch‐based non‐invasive molecularly imprinted polymer (MIP) electrochemical sensor for rapid, simple, and reliable stress‐free detection of sweat cortisol is described. The sensor readily measures fingertip sweat cortisol via highly selective binding to the cortisol‐imprinted electropolymerized polypyrrole coating. The MIP network is embedded with Prussian blue redox probes that offer direct electrical signaling of the binding event to realize sensitive label‐free amperometric detection. Using a highly permeable sweat‐wicking porous hydrogel, instantaneously secreted fingertip sweat can be conveniently and rapidly collected without any assistance. By eliminating time lags, such rapid (3.5 min) fingertip assay enables the capture of sharp variations in cortisol levels, compared to previous methods. Such advantages are demonstrated by tracking cortisol response in short cold‐pressor tests and throughout day‐long circadian rhythm, along with gold‐standard immunoassay validation. A stretchable epidermal MIP sensor is also described for directly tracking cortisol in exercise‐induced sweat. The rapid touch‐based cortisol sensor offers an attractive, accessible, stressless avenue for quantitative stress management.
Self‐Structural Healing of Encapsulated Perovskite Microcrystals for Improved Optical and Thermal Stability
Authors: Li Ruxue , Li Bobo , Fang Xuan , Wang Dengkui , Shi Yueqing , Liu Xiu , Chen Rui , Wei Zhipeng 
Published: March 2021

AbstractPerovskite materials and their optoelectronic devices have attracted intensive attentions in recent years. However, it is difficult to further improve the performance of perovskite devices due to the poor stability and the intrinsic deep level trap states (DLTS), which are caused by surface dangling bonds and grain boundaries. Herein, the CH3NH3PbBr3 perovskite microcrystal is encapsulated by a dense Al2O3 layer to form a microenvironment. Through optical measurement, it is found that the structure of perovskite can be healed by itself even under high temperature and long‐time laser illumination. The DLTS density decreases nearly an order of magnitude, which results in 4–14 times enhancement of light emission. The observation is ascribed to the micron‐level environment, which serves as a self‐sufficient high‐vacuum growth chamber, where the components of the perovskite are completely retained when sublimated and the decomposed atoms can re‐arrange after thermal treatment. The modified structure showing high thermal stability is able to maintain excellent optical and lasing stability up to 2 years. This discovery provides a new idea and perspective for improving the stability of perovskite and can be of practical interest for perovskite device application.
A Triboelectric‐Nanogenerator‐Based Gas–Solid Two‐Phase Flow Sensor for Pneumatic Conveying System Detecting
Authors: Wang Yan , Liu Dehua , Hu Zhiyuan , Chen Tianyu , Zhang Ziyi , Wang Hao , Du Taili , Zhang Steven L. , Zhao Zhiqiang , Zhou Tongming , Xu Minyi 
Published: March 2021

AbstractThe particle concentration and the mass flow rate are the most important parameters describing the gas–solid two‐phase flow. Herein, a novel method based on triboelectric nanogenerator is proposed for measuring a particle concentration and the mass flow rate in a gas–solid two‐phase pipe flow. The as‐fabricated gas–solid two‐phase flow triboelectric nanogenerator (GS‐TENG) consists of one acrylic base plate, one copper electrode, and one stripe of polytetrafluoroethylene (PTFE) membrane. Different materials can be detected by the GS‐TENG, including organic material, such as flour, and inorganic materials, such as copper and soil. PTFE surface morphology is modified to improve the output performance of the GS‐TENG in the experiments in order to detect the output electrical signal more efficiently. The peak output current generated by the gas–solid two‐phase flow in the GS‐TENG shows a mostly linear relationship with the concentration and mass flow rate. In addition, the transferred charge in the process of the flow also shows a highly linear relationship with the concentration and the mass flow rate, which is consistent with the theoretical derivation for the single electrode TENG. The experimental results demonstrate that the measurement error of the GS‐TENG is less than 2%.
Orbital‐Angular‐Momentum‐Encrypted Holography Based on Coding Information Metasurface
Authors: Xiao Qiang , Ma Qian , Yan Tao , Wu Liang Wei , Liu Che , Wang Zheng Xing , Wan Xiang , Cheng Qiang , Cui Tie Jun 
Published: March 2021

AbstractMetasurface holography has shown great potentials to reconstruct the full‐wave information of electromagnetic (EM) waves, bringing benefits of high spatial resolution and good precision of reconstructed images. To obtain higher security of the metasurface holography, orbital‐angular‐momentum (OAM) of EM waves is taken into consideration as new freedom of the metasurface holography. The use two coding information metasurfaces is proposed to achieve the OAM‐encrypted holography. One metasurface is used to generate different OAM beams with l = ±1 helical mode indices, which functions as the OAM feed; while the other is used to integrate different OAM helical‐phase wavefronts into the holograms of the transmitted images, forming the OAM‐encrypted holography. The predesigned images are accurately decoded only when the OAM‐encrypted metasurface is illuminated by the incident OAM beams with the inverse helical mode indices (l = ∓1) under the incidence of defined polarization states. Experimental results agree well with the theoretical design and numerical simulations, verifying the feasibility and security of the OAM‐encrypted holography. The proposed method will be a good candidate to enhance the secure communication systems and imaging systems.
One‐pot Synthesis of Isoquinoline‐Fused Isoquinolines via Intramolecular Hydroamination/Aza‐Claisen Type Rearrangement Cascade
Authors: Chiu Wei‐Jung , Chen Jin‐Yu , Liu Shih‐I , Barve Indrajeet J. , Huang Wan‐Wen , Sun Chung‐Ming 
Published: March 2021

AbstractA one‐pot, two‐step synthesis of isoquinoline‐fused isoquinolines from α‐amino acid esters and 2‐alkynyl benzaldehydes are reported. The strategy comprises an unconventional Pictet‐Spengler reaction between α‐amino acid esters and 2‐alkynyl benzaldehydes to give isoquinoline intermediates. Subsequent gold‐catalyzed intramolecular hydroamination furnishes isoquinoline‐fused isoquinolines. The scope of this strategy is further extended to prepare multisubstituted isoquinoline‐fused isoquinolines via subjecting the N‐allylated isoquinoline intermediates to gold‐catalyzed intramolecular hydroamination followed by aza‐Claisen type rearrangement.magnified image
Vinylogous Aza‐Michael Addition of Urea Derivatives with p‐Quinone Methides Followed by Oxidative Dearomative Cyclization: Approach to Spiroimidazolidinone Derivatives
Authors: Kaur Navpreet , Singh Priyanka , Banerjee Prabal 
Published: March 2021

AbstractHerein, we report an efficient protocol for the synthesis of spiro‐imidazolidinone‐cyclohexadienones from p‐quinone methides (p‐QMs) and dialkyloxy ureas under mild conditions. The strategy follows a two‐step process involving an initial vinylogous conjugate addition of urea derivatives to p‐QMs, followed by oxidative dearomative cyclization of open‐chain product to the projected spiro‐imidazolidinones. This protocol exhibits good functional group tolerance and provides a straightforward method to access spiro‐imidazolidinone‐cyclohexadienones. In follow‐up chemistry, we have shown the debenzylation of spiroimidazolidinones to give N‐hydroxycyclic ureas.magnified image
Ethylene Carbonate‐Free Propylene Carbonate‐Based Electrolytes with Excellent Electrochemical Compatibility for Li‐Ion Batteries through Engineering Electrolyte Solvation Structure
Authors: Liu Xingwei , Shen Xiaohui , Li Hui , Li Peng , Luo Laibing , Fan Haiman , Feng Xiangming , Chen Weihua , Ai Xinping , Yang Hanxi , Cao Yuliang 
Published: March 2021

AbstractPropylene carbonate (PC) ‐based electrolytes have many desirable advantageous properties compared to the currently used ethylene carbonate (EC) ‐based electrolytes for lithium ion batteries, however, their poor compatibility with the graphite anode hinders its applications. Here, a facile and effective strategy to make electrochemically compatible PC‐based electrolytes by use of a weakly coordinating diethyl carbonate co‐solvent to induce PF6− anions into the solvation shell of Li+ to form an anion‐induced ion–solvent‐coordinated (AI‐ISC) structure is reported. Such an AI‐ISC structure can lead to an increase of the lowest unoccupied molecular orbital energy level of the electrolyte, therefore considerably improving the reduction tolerance of the PC solvent. Furthermore, by using the film‐forming additive (fluoroethylene carbonate, FEC), an electrochemically stable, EC‐free PC‐based electrolyte, which enables reversible Li+ intercalation on the graphite electrode is obtained. The graphite/LiNi0.5Mn0.3Co0.2O2 pouch cells using this PC‐based electrolyte exhibit very similar room‐temperature electrochemical performance to those using conventional EC‐based electrolytes and excellent low‐temperature performance. This work provides a new approach to make EC‐free electrolytes with a similar AI‐ISC structure but without the need for a high concentration of Li salt of highly concentrated electrolytes, which may bring new insights in the development of advanced electrolyte systems for wide battery applications.
A Periplasmic Photosensitized Biohybrid System for Solar Hydrogen Production
Authors: Luo Bifu , Wang Yan‐Zhai , Li Di , Shen Hongqiang , Xu Li‐Xia , Fang Zhen , Xia Zhenglong , Ren Jianlin , Shi Weidong , Yong Yang‐Chun 
Published: March 2021

AbstractWhole‐cell inorganic‐biohybrid systems, integrating inorganic photosensitizers with intact living cells, have shown great potential for solar hydrogen production. However, the typical whole cell biohybrid system often suffers from the sluggish kinetics of electron transfer in the transmembrane diffusion process, which severely restrict their photocatalytic activity. Here, a unique periplasmic photosensitized biohybrid system is constructed by translocating CuInS2/ZnS quantum dots (QDs) into the Shewanella oneidensis MR‐1 (SW) cells that express periplasmic hydrogenases. The photoexcitation and electron transfer processes of QDs photosensitizers occur simultaneously in the periplasm of SW cells, which reduces the distance for electron transport and avoids the extra energy loss involved in the transmembrane process. As expected, the photocatalytic H2 generation of the fabricated biohybrid system is 8.6 times higher than that of bare QDs under visible light irradiation. Moreover, the good viability and stability of this biohybrid system endow it with an excellent sustained hydrogen production within 45 h, representing the most stable biohybrid among the reported whole‐cell biohybrid H2 production systems. This work provides a novel insight into the construction of a robust whole‐cell biohybrid system for solar hydrogen production.
Bis‐(Dibenzothiophene) Embedded Hexaphyrins: Synthesis, Structure and Properties
Authors: Sinha Avisikta , Kumar Ankit , Ravikanth Mangalampalli 
Published: March 2021

AbstractWe report our successful synthesis of two stable bis‐(dibenzothiophene) embedded hexaphyrins by condensing one equivalent of dibenzothiophene based tripyrrane with one equivalent of aryl aldehydes such as pentafluorobenzaldehyde and p‐nitrobenzaldehyde under acid catalysed conditions. The blue coloured dibenzothiophene (DBT) embedded hexaphyrins were characterised by various spectroscopic techniques. The X‐ray structure obtained for one of the DBT embedded hexaphyrins showed the unusual unique chair like conformation of the macrocycle which is similar to cyclohexane ring. The X‐ray crystallographic analysis was further supported by DFT studies. The NMR, absorption and DFT studies indicated the non‐aromatic nature of the macrocycles. TD‐DFT calculations successfully reproduced experimentally observed absorption spectra of bis‐(dibenzothiophene) embedded hexaphyrins.
Clinical Issues—April 2021
Authors: Burlingame Byron 
Published: March 2021

THIS MONTH
Scrubbed team members leaving the OR while x‐rays are taken
Key words: radiation source exposure, x‐ray, distance and shielding, radiation protection devices, inverse square law.
Cleaning radiation protection garments and devices
Key words: radiation protection, cleaning reusable garments, eyewear, lead aprons, shielding devices.
Implementing radiation precautions for pregnant health care workers
Key words: scatter radiation, shielding, dosimeter, pregnant health care worker, protective garment.
Protecting patients from radiation exposure
Key words: scatter radiation, radiation protection devices, radiation shielding, radiation protection drapes, patient exposure.
Wearing x‐ray aprons that fit correctly
Key words: body size, radiation protection garment sizing, x‐ray, lead aprons, anthropomorphic phantom.
High loading boron nitride chemically bonded with silicone rubber to enhance thermal neutron shielding and flexibility of polymer nanocomposites
Authors: Li Jia‐Le , Zhang Quan‐Ping , Liu Xue , Chen Rui‐Chao , Xu Wei‐Di , Sun Nan , Li Yin‐Tao , Yang Wen‐Bin , Xu Dui‐Gong , Zhou Yuan‐Lin 
Published: March 2021

AbstractFlexible materials with excellent radiation shielding and flexibility are essential to the personal protective equipments (PPEs) for protecting workers from nuclear radiations. However, it is an enormous challenge to obtain the desired materials since high loading filler in polymer nanocomposites usually promotes radiation shielding while restrains its flexibility. Here, a facile “thiol‐ene click” means is applied to chemically bond high loading boron nitride (BN) nanoparticles with silicone rubber (SR) in SR/BN nanocomposites for thermal neutron shielding. Uniform dispersion of BN nanoparticles and good compatibility of interfaces in the nanocomposites with high loading filler lead to increased flexibility instead of decrease. In particular, the nanocomposite with 40 wt% BN displays 911% of elongation at break that is about 50% enhancement to that of neat SR. Furthermore, higher loading BN in the nanocomposites means better thermal neutron shielding. Namely, enhanced thermal neutron shielding and flexibility is achieved at SR/BN nanocomposite with 40 wt% BN. The present work provides a facile strategy towards superior integrated performance of flexible materials for radiation shielding, such as wearable devices.
Limnological perspectives on conservation of floodplain lakes in the Amazon basin
Authors: Melack John M. , Kasper Daniele , Amaral João H.F. , Barbosa Pedro M. , Forsberg Bruce R. 
Published: March 2021

Abstract

Limnological aspects of Amazon floodplain lakes are examined in the context of aquatic conservation.
A prerequisite to detecting and evaluating changes that could threaten the ecological health and organisms in floodplain lakes is understanding variation under present conditions. Based on one of the few studies with regular measurements over 2 years, chlorophyll, total phosphorus, dissolved oxygen, transparency, and total suspended solids in Lake Janauacá indicate that the lake is naturally quite variable with a mesotrophic to eutrophic status.
Direct threats to ecological health of floodplain lakes include mining operations that can increase turbidity and trace metals and reduce nutritional quality of sediments. Mercury contamination and methylation leads to bioaccumulation in aquatic organisms.
Deforestation in uplands increases nitrogen and phosphorus inputs to floodplain lakes and can alter trophic status. Deforestation in floodable forests alters the habitat and food of the fish that inhabit these forests.
Cumulative limnological responses as catchments are altered by urban, agricultural, and industrial developments, and as inundation is altered by changes in climate and construction of dams, have major implications for the ecology of floodplain lakes.
To improve understanding and management of threats to the conservation of aquatic Amazon biota and ecosystems requires considerably expanded and coordinated research and community‐based management that includes the spectrum of floodplain lakes throughout the basin.
Successful use of Nicotiana tabacum hairy roots for the recombinant production of Cecropin A peptide
Authors: Hashemi Samaneh , Niazi Ali , Baghizadeh Amin , Taghizadeh Mohammad Sadegh 
Published: March 2021

AbstractCecropin A, as an antimicrobial peptide (AMP), is possible to use in medical and agricultural fields as a new and safe biocontrol agent. Therefore, it is highly necessary to find a cost‐effective and scalable approach to generate a large scale of it. In this research, the Agrobacterium rhizogenes strain ATCC 15834 was used to transfer the Cecropin A gene to the Nicotiana tabacum. After confirmation of transgenic hairy roots, the antibacterial activity of purified Cecropin A peptide was measured using the agar gel diffusion method. Successful transforming of Cecropin A was confirmed at the RNA and protein levels in hairy root cells using RT‐PCR and enzyme‐linked immunosorbent assay (ELISA), respectively. The highest Cecropin A amount was detected in line 4 of the transgenic lines using ELISA in comparison with the nontransgenic line. Subsequently, the antimicrobial activity of Cecropin A extracted from line 4 showed the highest inhibition activity against Aspergillus niger. Besides, this activity was stable against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Candida albicans pathogens after 7 days. The recombinant production of Cecropin A AMP had a yield of 63.81 μg/g of fresh weight. According to a significant yield, this system can be used to produce the Cecropin A peptide for pharmacological and food science applications.