bluuebunny/crossref_metadata_2025_split huggingface dataset:
Programmable and Thermally Hardening Composite Yarn Actuators with a Wide Range of Operating Temperature
Authors: Zhang Ziheng , Zhu Bo , Peng Zehua , Yin Rong , Baughman Ray H. , Tao Xiaoming 
Published: July 2020

AbstractActuators have wide applications in intelligent robots, deformable textiles, and wearable devices, wherein the fiber‐based coiled linear actuators are particularly advantageous due to their good flexibility, high stress, and strain. However, their performances have been limited by the employed materials, whose microstructures are not easily designed and controlled. This article proposes a new approach of engineered composite yarns for the actuators. It leads to novel solutions to overcome these difficulties by offering wide design options in material properties and device structures. Here, an engineering design of programmable and thermally‐hardening helical composite yarn actuators (HCYAs) with a wide range of operating temperature is exemplified. Polyimide (PI) and polydimethylsiloxane (PDMS) are selected to fabricate HCYAs, achieving tensile actuation of 20.7% under 1.2 MPa from −50 °C to 160 °C and competitive specific work (158.9 J kg‐1, four times of natural muscle). With constant tensile deformation, PI/PDMS HCYA nearly tripled the stress from 20 °C to 100 °C. Moreover, it is surprisingly observed an unusual thermal‐hardening phenomenon that the tensile stiffness of the PI/PDMS HCYAs increases with the rise of temperature. Equipped by electrothermally powered PI/Cu/PDMS HCYAs, robotic hands and pressure‐tunable compressive bandage are demonstrated for their potential applications in robots and wearable devices.
Designing Ordered Structure with Piezoceramic Actuation Units (OSPAU) for Generating Continual Nanostep Motion
Authors: Li Zhanmiao , Gao Xiangyu , Yang Jikun , Xin Xudong , Yi Xingyu , Bian Lang , Dong Shuxiang 
Published: July 2020

AbstractContinual precision actuations with nanoscale resolution over large ranges have extensive requirements in advanced intelligent manufacturing and precise surgical robots. To produce continual nanostep motion, conventionally, multiple pairs of piezo‐actuators are employed to operate in inchworm principle under complex three‐ or four‐phase timing signal drive. Inspired by the idea of ordered structures with functional units, a much simpler nanostep piezoelectric actuator consisting of (2 × 2) arrayed, cofired multilayer piezoceramic actuation units is developed, which operates in an artificially generated quasi shear mode (AGQSM) that is missing in natural piezoelectric ceramics. Under only one‐phase square‐wave voltage drive, the actuator can produce a stable, continual nanostep motion in two ways at nonresonant frequencies, and the obtained minimum step displacement is as low as 7 nm in open control, indicating its potential application as a precise finger or knife actuator in surgical robots. This work is of great guiding significance for future actuator designs using the methodology of ordered structure with piezoceramic actuation units and AGQSM.
High‐Yield Production of Biohybrid Microalgae for On‐Demand Cargo Delivery
Authors: Akolpoglu Mukrime Birgul , Dogan Nihal Olcay , Bozuyuk Ugur , Ceylan Hakan , Kizilel Seda , Sitti Metin 
Published: July 2020

AbstractBiohybrid microswimmers exploit the swimming and navigation of a motile microorganism to target and deliver cargo molecules in a wide range of biomedical applications. Medical biohybrid microswimmers suffer from low manufacturing yields, which would significantly limit their potential applications. In the present study, a biohybrid design strategy is reported, where a thin and soft uniform coating layer is noncovalently assembled around a motile microorganism. Chlamydomonas reinhardtii (a single‐cell green alga) is used in the design as a biological model microorganism along with polymer–nanoparticle matrix as the synthetic component, reaching a manufacturing efficiency of ≈90%. Natural biopolymer chitosan is used as a binder to efficiently coat the cell wall of the microalgae with nanoparticles. The soft surface coating does not impair the viability and phototactic ability of the microalgae, and allows further engineering to accommodate biomedical cargo molecules. Furthermore, by conjugating the nanoparticles embedded in the thin coating with chemotherapeutic doxorubicin by a photocleavable linker, on‐demand delivery of drugs to tumor cells is reported as a proof‐of‐concept biomedical demonstration. The high‐throughput strategy can pave the way for the next‐generation generation microrobotic swarms for future medical active cargo delivery tasks.
Recent Developments on the Synthesis of Various Sulfur‐Containing Heterocycles via [3+2]‐ and [4+2]‐Cycloaddition Reactions with Thiocarbonyls
Authors: Jaiswal Vandana , Mondal Biplab , Saha Jaideep 
Published: July 2020

AbstractThis minireview summarizes important collection of cycloaddition strategies that were used for the synthesis of sulfur‐containing five‐ and six‐membered heterocycles from thiocarbonyl‐based synthons. Among various stepwise or concerted methods available to prepare thioheterocycles, cycloaddition reactions of thiocarbonyls in particular present an important class of reaction owing to their ability to function as super dipolarophiles and/or superdienophiles. Design and development of various reactions in recent years with thiocarbonyls have certainly superseded the general purview on this reactive synthon that it often leads to side reaction and oligomerization. This article, apart from including the advances in the known reaction manifold of thiocarbonyls, also provide updates on new developments of cycloaddition chemistry, which includes donor‐acceptor (D−A) cyclopropanes and azaoxyallyl cation as 1,3‐dipolar reaction partners. This review should serve the purpose of an important guiding tool for organic and medicinal chemist to design and develop new class of cycloaddition or related transformations with thiocarbonyls for the preparation of novel heterocycles.
Identification of Histone deacetylase (HDAC)‐Associated Proteins with DNA‐Programmed Affinity Labeling
Authors: Zhang Jianfu , Peng Jianzhao , Huang Yiran , Meng Ling , Li Qingrong , Xiong Feng , Li Xiaoyu 
Published: July 2020

AbstractHistone deacetylase (HDAC) is a major class of deacetylation enzymes. Many HDACs exist in large protein complexes in cells and their functions strongly depend on the complex composition. The identification of HDAC‐associated proteins is highly important in understanding their molecular mechanisms. Although affinity probes have been developed to study HDACs, they were mostly targeting the direct binder HDAC, while other proteins in the complex remain underexplored. We report a DNA‐based affinity labeling method capable of presenting different probe configurations without the need for preparing multiple probes. Using one binding probe, 9 probe configurations were created to profile HDAC complexes. Notably, this method identified indirect HDAC binders that may be inaccessible to traditional affinity probes, and it also revealed new biological implications for HDAC‐associated proteins. This study provided a simple and broadly applicable method for characterizing protein‐protein interactions.
Immobilization of an Iridium Pincer Complex in a Microporous Polymer for Application in Room‐Temperature Gas Phase Catalysis
Authors: König Michaela , Rigo Massimo , Chaoui Nicolas , Tran Ngoc Trung , Epping Jan Dirk , Schmidt Johannes , Pachfule Pradip , Ye Meng‐Yang , Trunk Matthias , Teichert Johannes F. , Drieß Matthias , Thomas Arne 
Published: July 2020

AbstractAn iridium dihydride pincer complex [IrH2(POCOP)] is immobilized in a hydroxy‐functionalized microporous polymer network using the concepts of surface organometallic chemistry. The introduction of this novel, truly innocent support with remote OH‐groups enables the formation of isolated active metal sites embedded in a chemically robust and highly inert environment. The catalyst maintained high porosity and without prior activation exhibited efficacy in the gas phase hydrogenation of ethene and propene at room temperature and low pressure. The catalyst can be recycled for at least four times.
Exerting Spatial Control During Nanoparticle Occlusion within Calcite Crystals
Authors: Ning Yin , Han Yide , Han Lijuan , Derry Matthew J. , Armes Steven P. 
Published: July 2020

AbstractIn principle, nanoparticle occlusion within crystals provides a straightforward and efficient route to make new nanocomposite materials. However, developing a deeper understanding of the design rules underpinning this strategy is highly desirable. In particular, controlling the spatial distribution of the guest nanoparticles within the host crystalline matrix remains a formidable challenge. Herein, we show that the surface chemistry of the guest nanoparticles and the [Ca2+] concentration play critical roles in determining the precise spatial location of the nanoparticles within calcite crystals. Moreover, in situ studies provide important mechanistic insights regarding surface‐confined nanoparticle occlusion. Overall, this study not only provides useful guidelines for efficient nanoparticle occlusion, but also enables the rational design of patterned calcite crystals using model anionic block copolymer vesicles.
A Divergent Enantioselective Total Synthesis of Post‐Iboga Indole Alkaloids
Authors: Zhou Jie , Tan Dong‐Xing , Han Fu‐She 
Published: July 2020

AbstractDivergent enantioselective total syntheses of five naturally occurring post‐iboga indole alkaloids, dippinine B and C, 10,11‐demethoxychippiine, 3‐O‐methyl‐10,11‐demethoxychippiine, and 3‐hydroxy‐3,4‐secocoronaridine, as well as the two analogues 11‐demethoxydippinine A and D, are presented for the first time. The enantioenriched aza[3.3.1]‐bridged cycle, a common core intermediate to the target molecules, was constructed through an asymmetric phase‐transfer‐catalyzed Michael/aldol cascade reaction. The challenging azepane ring fused around the indole ring and the [3.3.1]‐bridged cycle were installed through an intramolecular SN2′‐type reaction. These cyclization strategies enabled rapid construction of the [6.5.6.6.7]‐pentacyclic core at an early stage. Highlights of the late‐stage synthetic steps include a Pd‐catalyzed Stille coupling and a highly stereoselective catalyst‐controlled hydrogenation to incorporate the side chain at C20 with both R and S configurations in the natural products.
Challenges in monitoring mobile populations: Applying bayesian multi‐site mark–recapture abundance estimation to the monitoring of a highly mobile coastal population of bottlenose dolphins
Authors: Nykänen Milaja , Oudejans Machiel G. , Rogan Emer , Durban John W. , Ingram Simon N. 
Published: July 2020

Abstract

Monitoring the abundance of mobile and wide‐ranging cetacean populations for conservation management is challenging, especially when the management is focused on static protected areas. Where abundance estimates are derived from mark–recapture data, such as photo‐identification of naturally marked individuals, unpredictable movements of animals in and out of the survey area can reduce ‘capture’ probabilities and affect the precision and accuracy of resulting estimates.
A Bayesian hierarchical log–linear model was applied to photo‐identification data collected in summer 2014 to derive a multi‐site abundance estimate for a population of bottlenose dolphins, Tursiops truncatus, ranging widely throughout the coastal waters of western Ireland. In addition, the effects of varying levels of sampling effort on the minimum detectable decrease in population size were examined.
The abundance (median) of dolphins was estimated as 189 (coefficient of variation (standard deviation/mean), 0.11; 95% highest‐posterior density interval, 162–232). Over 50% of the well‐marked dolphins encountered throughout the study were sighted in more than one distinct coastal area, thus displaying high mobility. In addition, it was found that it would require biennial surveys to detect a 25% decline in abundance within the six‐year reporting period of the EU’s Habitats Directive.
Given that the Special Area of Conservation designated for these dolphins consists of two separate areas covering a substantial portion of the west coast of Ireland, the multisite approach is appropriate for monitoring this population. It produces a more precise estimate and is well suited for sparse recapture data collected opportunistically at multiple sites, when the lack of resources prevents large‐scale surveys or when concentrating surveys on smaller localized areas fails to capture the broad range and unpredictable occurrence of the animals. The Bayesian multi‐site approach could be applied to the management of other wide‐ranging marine or terrestrial taxa.
Introduction to a special issue on kidney development and disease
Authors: Sutherland Megan R. 
Published: July 2020

AbstractEnriching our understanding of the anatomy of the kidneys, in development, health, and disease, has been the primary focus of Professor John Bertram's distinguished research career to date. Among other notable achievements, his landmark analyses of nephron number in over 400 human kidneys (the Monash Series), and his refinement of stereological techniques for renal structural analyses, have proven him an international leader in renal anatomy research. In this Special Issue, we (some of John's collaborators, colleagues, and former students) celebrate John's career with a series of 20 review and original research articles relevant to his expertise: (a) renal anatomy, physiology, and pathology, (b) kidney development, podocyte biology, and applications of renal stem cells, (c) renal developmental programming, and (d) contemporary methodologies in renal research; his accomplishments as a Head (Chair) of an Anatomy Department are also illustrated. We hope that this collection will serve as both an important resource, and a source of inspiration, to renal anatomy researchers and educators alike.
Recent Advances in the Preparation and Applications of Organo‐functionalized Porous Materials
Authors: Yadav Rekha , Baskaran Thangaraj , Kaiprathu Anjali , Ahmed Maqsood , Bhosale Sheshanath V. , Joseph Stalin , Al‐Muhtaseb Ala'a H. , Singh Gurwinder , Sakthivel Ayyamperumal , Vinu Ajayan 
Published: July 2020

AbstractOrgano‐functionalized materials with porous structure offer unique adsorption, catalytic and sensing properties. These unique properties make them available for various applications, including catalysis, CO2 capture and utilization, and drug delivery. The properties and the performance of these unique materials can be altered with suitable modifications on their surface. In this review, we summarize the recent advances in the preparation and applications of organo‐functionalized porous materials with different structures. Initially, a brief historical overview of functionalized porous materials is presented, and the subsequent sections discuss the recent developments and applications of various functional porous materials. In particular, the focus is given on the various methods used for the preparation of organo‐functionalized materials and their important roles in the heterogenization of homogeneous catalysts. A special emphasis is also given on the applications of these functionalized porous materials for catalysis, CO2 capture and drug delivery.
Functional analysis of mesencephalic astrocyte‐derived neurotrophic factor in retinal ganglion cells under oxidative stress
Authors: Ko Ji‐Ae , Komatsu Kaori , Okumichi Hideaki , Kiuchi Yoshiaki 
Published: July 2020

Glaucoma is optic neuropathy that is characterized by progressive neurodegeneration of the retinal ganglion cells (RGCs) and axons. This condition will lead to visual impairment and bring glaucoma to become the second cause of blindness globally. Neuroprotection in glaucoma is needed to prevent the progression of optic neuropathy. In this study, we examined the effects of the superior colliculus (SC), and mesencephalic astrocyte‐derived neurotrophic factor (MANF) secreted from the SC, on RGC survival after oxidative stress. SC slices and RGCs from rats (3‐day old) were co‐cultured using a 3D‐transwell system. In addition, primary RGCs from 4 to 5‐day‐old rats were cultured and treated with 100 μM hydrogen peroxide (H2O2), together with stimulation by MANF. Immunoblot and immunofluorescence analyses indicated down‐regulated expression levels of several survival markers of RGCs. Extension of neurites was decreased in RGCs treated with 100 μM H2O2. Following co‐culture with SC slices, or the addition of MANF, we found that both the down‐regulated expression of neural markers and extension of neurites caused by oxidative stress in RGCs were blocked. Furthermore, we found a decrease in the expression of neural markers and extension of neurites after co‐culture with MANF siRNA‐treated SC slices compared with slices treated with mock siRNA, but, RGCs co‐cultured with SC slices treated with MANF siRNA displayed no‐changed about to apoptosis. These results suggest that MANF secreted from the SC may play an important role in maintenance of function and survival of RGCs. It is also possible that MANF is an important factor in neuroprotection of RGCs.Significance of the StudyGlaucoma is a progressive neurodegenerative disease of the retinal ganglion cell (RGC) and their axons. Neuroprotection is aimed at protecting those neurons that are damaged glaucomatous optic neuropathy. We have now examined the effects of superior colliculus, or msencephalic astrocyte‐derived neutrophic factor (MANF), secreted from superior colliculus, on RGC survival using co‐culture system. Our results suggested that MANF may important key factor in neuroprotection of RGC.
Minisci C−H Alkylation of Heteroarenes Enabled by Dual Photoredox/Bromide Catalysis in Micellar Solutions**
Authors: Santos Marilia S. , Cybularczyk‐Cecotka Martyna , König Burkhard , Giedyk Maciej 
Published: July 2020

AbstractAromatic heterocycles are omnipresent structural motifs in various natural products, pharmaceuticals and agrochemicals. This work describes a photocatalytic Minisci‐type C−H functionalization of heteroarenes with non‐activated alkyl bromides. The reaction avoids stoichiometric radical‐promoters, oxidants, or acids, and is conducted using blue LEDs as the light source. The reactive carbon‐centered alkyl radicals are generated by merging the photoredox approach with bromide anion co‐catalysis and spatial pre‐aggregation of reacting species in the micellar aqueous solutions. The obtained data highlight the critical importance of microstructuring and organization of the components in the reaction mixture.
Altering Charges on Heterobimetallic Transition‐Metal Carbonyl Clusters
Authors: Unkrig Wiebke , Kloiber Konstantin , Butschke Burkhard , Kratzert Daniel , Krossing Ingo 
Published: July 2020

AbstractThe homoleptic group 5 carbonylates [M(CO)6]− (M=Nb, Ta) serve as ligands in carbonyl‐terminated heterobimetallic AgmMn clusters containing 3 to 11 metal atoms. Based on our serendipitous [Ag6{Nb(CO)6}4]2+ (4 a2+) precedent, we established access to such AgmMn clusters of the composition [Agm{M(CO)6}n]x (M=Nb, Ta; m=1, 2, 6; n=2, 3, 4, 5; x=1−, 1+, 2+). Salts of those molecular cluster ions were synthesized by the reaction of [NEt4][M(CO)6] and Ag[Al(ORF)4] (RF=C(CF3)3) in the correct stoichiometry in 1,2,3,4‐tetrafluorobenzene at −35 °C. The solid‐state structures were determined by single‐crystal X‐ray diffraction methods and, owing to the thermal instability of the clusters, a limited scope of spectroscopic methods. In addition, DFT‐based AIM calculations were performed to provide an understanding of the bonding within these clusters. Apparently, the clusters 3+ (m=6, n=5) and 42+ (m=6, n=4) are superatom complexes with trigonal‐prismatic or octahedral Ag6 superatom cores. The [M(CO)6]− ions then bind through three CO units as tridentate chelate ligands to the superatom core, giving overall structures related to tetrahedral AX4 (42+) or trigonal bipyramidal AX5 molecules (3+).
Greatly Enhanced Electrocatalytic N2 Reduction over V2O3/C by P Doping
Authors: Cheng Xin , Wang Jianwei , Xiong Wei , Wang Ting , Wu Tongwei , Lu Siyu , Chen Guang , Gao Shuyan , Shi Xifeng , Jiang Zhenju , Niu Xiaobin , Sun Xuping 
Published: July 2020

AbstractAs a carbon‐neutral alternative technology to the Haber−Bosch process, electrochemical N2 reduction enables eco‐friendly NH3 synthesis under ambient conditions but requires electrocatalysts to drive the N2 reduction reaction (NRR). Here, P doping is proposed as a valid strategy to greatly increase the NRR activity of the V2O3/C shuttle‐like nanostructure. In 0.1 M Na2SO4, the NH3 yield of original V2O3/C is 12.6 μg h−1 mg−1cat. and a Faraday efficiency (FE) of 6.06% at −0.45 V and −0.25 V vs. reversible hydrogen electrode (RHE), respectively. P‐doped V2O3/C (P−V2O3/C), with a mass ratio of P of 6.05%, is capable of achieving a large NH3 yield of 22.4 μg h−1 mg−1cat. at −0.35 V vs. RHE, and a high FE of 13.78% at −0.25 V vs. RHE. It also shows high electrochemical durability and outstanding selectivity for NH3 formation. Combined with density functional theory calculations, the catalytic mechanism was further explored.
Research on kick motion before Sanda based on 3D wireless sensor network image
Authors: Huang Lu , Song Jeho , Lin Xuejiao , Du Yachao , Yang Sidi 
Published: July 2020

SummaryThe biomechanical analysis of the pushing kick in the conventional free combat was aimed at the crowds with different ages and different types of skeletal muscles. The analysis precision was low. Therefore, this article put forward the biomechanical analysis of push‐kick of free combat based on 3D image. Three‐dimensional image technique and Hill equation were used to construct the biomechanical model of muscles of free‐combat athletes and describe the leg mechanics in the kicking process. Pattern system provides an up‐to‐date and authoritative fuzzy model, which is an intelligent recognition algorithm. Then, the image analysis was used to build the motion model of knee joint, so as to determine the dynamic equation of knee joint of pushing kick. Based on the above model, the characteristics such as the strike force of push kick, the peak characteristic of leg joint angular velocity and the joint torque were analyzed to achieve the biomechanical analysis of the pushing kick in free combat. Experimental data show that combined the proposed biomechanical analysis method with the traditional analysis method, the precision has improved by 47.69%. Meanwhile, it is suitable for the biomechanics analysis of different free combat crowds.
Quantitative Imaging of B1 Cyclin Expression Across the Cell Cycle Using Green Fluorescent Protein Tagging and Epifluorescence
Authors: Karuna Arnica , Masia Francesco , Chappell Sally , Errington Rachel , Hartley Andrew M. , Jones Darran Dafydd , Borri Paola , Langbein Wolfgang 
Published: July 2020

AbstractIn this article, we report the number of cyclin B1 proteins tagged with enhanced green fluorescent protein (eGFP) in fixed U‐2 OS cells across the cell cycle. We use a quantitative analysis of epifluorescence to determine the number of eGFP molecules in a nondestructive way, and integrated over the cell we find 104 to 105 molecules. Based on the measured number of eGFP tagged cyclin B1 proteins, knowledge of cyclin B1 dynamics through the cell cycle, and the cell morphology, we identify the stages of cells in the cell cycle. © 2020 The Authors. Cytometry Part A published by Wiley Periodicals LLC. on behalf of International Society for Advancement of Cytometry.