bluuebunny/crossref_metadata_2025_split huggingface dataset:
Semiotics as a philosophical and methodological, natural science and mathematical discipline (main stages of development and perspective)
Authors: Rozin Vadim Markovich 
Published: July 2022

The article examines the history of the development of the ideas of semiotics, from the works of St. Augustine to the present. The author shares the semiotic approach, which, judging by the literature, was formulated by Augustine, and semiotics as a scientific discipline, and in two versions, as an analogue of mathematics and natural science (we are talking about the "second nature", which is studied in the humanities and social sciences). The characteristic of the semiotic approach presented by Augustine in the scheme is given, which, the author shows, can be extended to various humanitarian objects (this is specifically demonstrated with respect to music). Based on the semiotic approach and classifications of signs, various variants of semiotics as a science were created in the XIX and XX centuries. The difference of scientific semiotics is explained: semiotics solved different problems and tasks, semiotically comprehended different subject areas, proceeded from a different understanding of science. Nevertheless, in all variants of semiotics, relations between the components of the sign were established. The semiotics reform project proposed by G.P. Shchedrovitsky is considered, and what came of it (another semiotics, and not the organization of different scientific semiotics on a single basis of the theory of activity). Based on the analysis of two cases (the semiotic analysis of the metaphor in the work of Meir Shalev "Esav" and the sculpture of Aphrodite Praxiteles), the author outlines another version of semiotics, which he calls "expressionism". Although the methodology proposed by him allows analyzing and comprehending a fairly wide range of expressions and works of art, the author suggests not to consider it universal.
Toward Hierarchical Assembly of Aligned Cell Sheets into a Conical Cardiac Ventricle Using Microfabricated Elastomers
Authors: Mohammadi Mohammad Hossein , Okhovatian Sargol , Savoji Houman , Campbell Scott B. , Lai Benjamin Fook Lun , Wu Jun , Pascual‐Gil Simon , Bannerman Dawn , Rafatian Naimeh , Li Ren‐Ke , Radisic Milica 
Published: July 2022

AbstractDespite current efforts in organ‐on‐chip engineering to construct miniature cardiac models, they often lack some physiological aspects of the heart, including fiber orientation. This motivates the development of bioartificial left ventricle models that mimic the myofiber orientation of the native ventricle. Herein, an approach relying on microfabricated elastomers that enables hierarchical assembly of 2D aligned cell sheets into a functional conical cardiac ventricle is described. Soft lithography and injection molding techniques are used to fabricate micro‐grooves on an elastomeric polymer scaffold with three different orientations ranging from −60° to +60°, each on a separate trapezoidal construct. The width of the micro‐grooves is optimized to direct the majority of cells along the groove direction and while periodic breaks are used to promote cell–cell contact. The scaffold is wrapped around a central mandrel to obtain a conical‐shaped left ventricle model inspired by the size of a human left ventricle 19 weeks post‐gestation. Rectangular micro‐scale holes are incorporated to alleviate oxygen diffusional limitations within the 3D scaffold. Cardiomyocytes within the 3D left ventricle constructs showed high viability in all layers after 7 days of cultivation. The hierarchically assembled left ventricle also provided functional readouts such as calcium transients and ejection fraction.
Mechanism and Kinetics of the Thermal Decomposition of Fe(C5H5)2 in Inert and Reductive Atmosphere: A Synchrotron‐Assisted Investigation in A Microreactor
Authors: Grimm Sebastian , Hemberger Patrick , Kasper Tina , Atakan Burak 
Published: July 2022

AbstractThe decomposition and reduction of ferrocene, an important precursor for iron chemical vapor deposition and catalyst for nanotube synthesis, is investigated in the gas‐phase. Reactive intermediates are detected to understand the underlying chemistry by using a microreactor coupled to a synchrotron light source. Utilizing soft photoionization coupled with photoelectron‐photoion coincidence detection enables us to characterize exclusive intermediates isomer‐selectively. A reaction mechanism for the ferrocene decomposition is proposed, which proceeds as a two‐step process. Initially, the molecule decomposes in a homogeneous surface reaction at temperatures <900 K, leading to products such as cyclopentadiene and cyclopentadienyl radicals that are immediately released to the gas‐phase. At higher temperatures, ferrocene rapidly decomposes in the gas‐phase, losing two cyclopentadienyl radicals in conjunction with iron. The addition of hydrogen to the reaction mixture reduces the decomposition temperature, and changes the branching ratio of the products. This change is mainly attributed to the H‐addition of cyclopentadienyl radicals on the surface, which leads to a release of cyclopentadiene into the gas‐phase. On the surface, ligand fragments may also undergo a series of catalytic H‐losses leading most probably to a high carbon content in the film. Finally, Arrhenius parameters for both global reactions are presented.
Dynamically Monitoring pH in Living Organisms Based on a SERS‐Active Optical Fiber
Authors: Pan Chenyan , Zhang Shuyu , Xiong Xiulei , Li Zhe , Ai Bingwei , Qian Weiping , Dong Jian 
Published: July 2022

AbstractTo dynamically monitor pH in living organisms, a pH‐sensitive surface‐enhanced Raman scattering (SERS)‐active optical fiber is designed and developed. A 2‐cm‐long optical fiber is processed with an inclined end to facilitate entering the body of the optical fiber, and a hole is etched near the inclined end to integrate pH‐sensitive SERS probes and protect them from being erased during entering the body. The pH‐sensitive SERS probes in the hole respond thoroughly to the buffer environment in 5 min and the body environment in 15 min, respectively. The fabricated SERS‐active optical fiber is used to dynamically monitor the change in pH in tissues of living rats, such as muscle and brain. The SERS‐active optical fibers will be a versatile platform to integrate optical probes such as SERS probes and fluorescence probes to dynamically monitor life activities in living organisms.
Gradient Droplet Arrays by Acceleration‐Mode Dip‐Coating
Authors: Mandsberg Nikolaj K. , Shneidman Anna V. , Jensen Kaare H. , Taboryski Rafael , Nielsen Line H. , Aizenberg Joanna , Boisen Anja 
Published: July 2022

AbstractDroplet microarray technology is of great interest in biology and chemistry as it allows for significant reactant savings and massive parallelization of experiments. Upon scaling down the footprint of each droplet in an array, it becomes increasingly challenging to produce the array drop‐by‐drop. Therefore, techniques for parallelized droplet production are developed, e.g., dip‐coating of biphilic substrates. However, it is in general difficult to tailor the characteristics of individual droplets, such as size and content, without updating the substrate. Here, the method of dip‐coating of uniformly patterned biphilic substrates in so‐called “acceleration‐mode” to produce droplet arrays featuring gradients in droplet height for fixed droplet footprint is developed. The results herein present this method applied to produce drops with base diameters varying over orders of magnitude, from as high as 6 mm to as small as 50 µm; importantly, the experimentally measured power‐law‐dependency of volume on capillary‐number matches analytical theory for droplet formation on heterogenous substrates though the precise quantitative values likely differ due to 2D substrate patterning. Gradient characteristics, including average droplet volume, steepness of the gradient, and its monotonicity, can all be tuned by changing the dip‐coating parameters, thus providing a robust method for high‐throughput screening applications and experiments.
Esaki Diode Behavior in Highly Uniform MoS2/Silicon Carbide Heterojunctions
Authors: Giannazzo Filippo , Panasci Salvatore E. , Schilirò Emanuela , Roccaforte Fabrizio , Koos Antal , Nemeth Miklos , Pécz Béla 
Published: July 2022

AbstractThe heterogeneous integration with 2D materials enables new functionalities and novel devices in state‐of‐the‐art bulk (3D) semiconductors. In this work, highly uniform MoS2 heterostructures with silicon carbide (4H‐SiC) are obtained by a facile synthesis method, highly compatible with semiconductor fab processing, i.e., the sulfurization of predeposited very‐thin (≈1.2 nm) Mo films at a temperature of 700 °C. Current–voltage characteristics of MoS2/n+‐4H‐SiC junctions collected by conductive atomic force microscopy show a pronounced negative differential resistance even at room temperature, which is a typical manifestation of band‐to‐band tunneling between degenerately p+‐/n+‐doped semiconductors. Here, the degenerate p+‐type doping of MoS2, with Nholes ≈ 4 × 1019 cm−3 evaluated by Raman mapping, is ascribed to the significant MoO3 content in the film, as demonstrated by X‐ray photoelectron spectroscopy analyses. Furthermore, atomic resolution transmission electron microscopy analyses reveal the presence of an ultrathin (≈1 nm) SiO2 tunneling barrier between MoS2 and 4H‐SiC, formed during the sulfurization process. The observation of Esaki diode behavior in MoS2 heterojunctions with 4H‐SiC opens new perspectives for this material system as a platform for ultrafast low‐power consumption digital applications.
Metasurface‐Assisted Optical Encryption Carrying Camouflaged Information
Authors: Deng Juan , Li Zile , Li Jiaxin , Zhou Zhou , Gao Fan , Qiu Chenghao , Yan Bo 
Published: July 2022

AbstractThe superior capability of light manipulation makes optical metasurfaces capable of high‐quality multichannel displays, demonstrating great potential in high‐security optical encryption. Different from the previous multichannel nanoprinting metasurfaces based on the sophisticated nanostructure design, Malus metasurface can obtain multichannel meta‐images only by arranging the orientations of single‐sized nanostructures and thus have gained great attention. Here, an optical encryption scheme based on single‐sized nanostructures is proposed by introducing camouflage strategy into Malus metasurfaces design processes to store multiple meta‐images in different encryption levels. Experimental results demonstrate that the preset camouflage meta‐image can be decoded by inserting a filter and a polarizer in the incident light path, while the decryption of real meta‐image requires not only the insertion of a filter and polarizer in the incident optical path, but also the insertion of an analyzer in the outgoing optical path and setting them to the specific polarization direction. This work eliminates the consistency of encryption level in conventional multi‐channel Malus metasurface, builds the differences of preset camouflage information and real information in decryption difficulty, and easily merges with other works, thereby paving a new way toward a high‐security optical encryption technology.
An Umpolung Route to Amides from α‐Aminonitriles under Metal‐Free Conditions
Authors: Swetha Sathyendran , Chandru Senadi Gopal 
Published: July 2022

AbstractA metal‐free, base‐mediated decyanation of α‐aminonitriles has been developed to synthesize secondary and tertiary amides using O2 or air as an amide oxygen source. Radical scavenging studies disclosed that the cleavage of C−CN bond may proceed via an anionic pathway. The practicality of the work was also demonstrated through an in situ generated α‐aminonitriles from corresponding aldehydes and amines to afford amides. The important features of this work include broad functional group compatibility, 41% to 89% product yields, gram‐scale synthesis of 2° and 3° amides, broad substrate scope, and an umpolung strategy.magnified image
Harnessing cGAS‐STING Pathway for Cancer Immunotherapy: From Bench to Clinic
Authors: Lee DaeYong , Huntoon Kristin , Kang Minjeong , Lu Yifei , Gallup Thomas , Jiang Wen , Kim Betty Y. S. 
Published: July 2022

AbstractRecent advances in cancer immunotherapy have accomplished clinical successes in certain cancer models over the past decade. However, cancer treatments with adoptive cell transfer or immune checkpoint blockade (ICB) have shown critical limitations against solid tumors, which comprise the majority of human cancers. Thus, novel cancer immunotherapy which harnesses innate immunity process may be required in these tumor types. Cyclic GMP‐AMP synthase (cGAS)‐stimulator of interferon genes (STING) pathway, one of the innate immune sensors, has gained interest in the field of immuno‐oncology as activation of this pathway can drive both innate and adaptive immune responses among immunosuppressive tumor microenvironments. Recently, various cGAS‐STING‐activating strategies have been intensively investigated to achieve durable and widespread therapeutic responses in in vivo models. These meaningful preclinical outcomes have enabled several clinical trials. This review discusses agents targeting various aspects of the cGAS‐STING pathway in cancer immunotherapy from benchtop to bedside. Moreover, various approaches to improve the clinical feasibility of cGAS‐STING‐activating strategies are delineated.
In Situ Generation of Ultrathin MoS2 Nanosheets in Carbon Matrix for High Energy Density Photo‐Responsive Supercapacitors
Authors: Tang Zhenbin , Dai Juguo , Wei Wenkang , Gao Zhi , Liang Zhixuan , Wu Chenzhi , Zeng Birong , Xu Yiting , Chen Guorong , Luo Weiang , Yuan Conghui , Dai Lizong 
Published: July 2022

AbstractStimuli‐responsive supercapacitors have attracted broad interest in constructing self‐powered smart devices. However, due to the demand for high cyclic stability, supercapacitors usually utilize stable or inert electrode materials, which are difficult to exhibit dynamic or stimuli‐responsive behavior. Herein, this issue is addressed by designing a MoS2@carbon core‐shell structure with ultrathin MoS2 nanosheets incorporated in the carbon matrix. In the three‐electrode system, MoS2@carbon delivers a specific capacitance of 1302 F g−1 at a current density of 1.0 A g−1 and shows a 90% capacitance retention after 10 000 charging‐discharging cycles. The MoS2@carbon‐based asymmetric supercapacitor displays an energy density of 75.1 Wh kg−1 at the power density of 900 W kg−1. Because the photo‐generated electrons can efficiently migrate from MoS2 nanosheets to the carbon matrix, the assembled photo‐responsive supercapacitor can answer the stimulation of ultraviolet‐visible‐near infrared illumination by increasing the capacitance. Particularly, under the stimulation of UV light (365 nm, 0.08 W cm−2), the device exhibits a ≈4.50% (≈13.9 F g−1) increase in capacitance after each charging‐discharging cycle. The study provides a guideline for designing multi‐functional supercapacitors that serve as both the energy supplier and the photo‐detector.
Opportunities and Challenges of Li2C4O4 as Pre‐Lithiation Additive for the Positive Electrode in NMC622||Silicon/Graphite Lithium Ion Cells
Authors: Gomez‐Martin Aurora , Gnutzmann Maike Michelle , Adhitama Egy , Frankenstein Lars , Heidrich Bastian , Winter Martin , Placke Tobias 
Published: July 2022

AbstractSilicon (Si)‐based negative electrodes have attracted much attention to increase the energy density of lithium ion batteries (LIBs) but suffer from severe volume changes, leading to continuous re‐formation of the solid electrolyte interphase and consumption of active lithium. The pre‐lithiation approach with the help of positive electrode additives has emerged as a highly appealing strategy to decrease the loss of active lithium in Si‐based LIB full‐cells and enable their practical implementation. Here, the use of lithium squarate (Li2C4O4) as low‐cost and air‐stable pre‐lithiation additive for a LiNi0.6Mn0.2Co0.2O2 (NMC622)‐based positive electrode is investigated. The effect of additive oxidation on the electrode morphology and cell electrochemical properties is systematically evaluated. An increase in cycle life of NMC622||Si/graphite full‐cells is reported, which grows linearly with the initial amount of Li2C4O4, due to the extra Li+ ions provided by the additive in the first charge. Post mortem investigations of the cathode electrolyte interphase also reveal significant compositional changes and an increased occurrence of carbonates and oxidized carbon species. This study not only demonstrates the advantages of this pre‐lithiation approach but also features potential limitations for its practical application arising from the emerging porosity and gas development during decomposition of the pre‐lithiation additive.
Narrowing the Phase Distribution of Quasi‐2D Perovskites for Stable Deep‐Blue Electroluminescence
Authors: Nah Yoonseo , Solanki Devan , Dong Yitong , Röhr Jason A. , Taylor André D. , Hu Shu , Sargent Edward H. , Kim Dong Ha 
Published: July 2022

AbstractSolution‐processed quasi‐2D perovskites contain multiple quantum wells with a broad width distribution. Inhomogeneity results in the charge funneling into the smallest bandgap components, which hinders deep‐blue emission and accelerates Auger recombination. Here, a synthetic strategy applied to a range of quasi‐2D perovskite systems is reported, that significantly narrows the quantum well dispersity. It is shown that the phase distribution in the perovskite film is significantly narrowed with controlled, simultaneous evaporation of solvent and antisolvent. Modulation of film formation kinetics of quasi‐2D perovskite enables stable deep‐blue electroluminescence with a peak emission wavelength of 466 nm and a narrow linewidth of 14 nm. Light emitting diodes using the perovskite film show a maximum luminance of 280 cd m–2 at an external quantum efficiency of 0.1%. This synthetic approach will serve in producing new materials widening the color gamut of next‐generation displays.
A Real‐Time In Situ Demonstration of Direct and Indirect Transformation Pathways in CdTe Magic‐Size Clusters at Room Temperature
Authors: Luan Chaoran , Shen Qiu , Rowell Nelson , Zhang Meng , Chen Xiaoqin , Huang Wen , Yu Kui 
Published: July 2022

AbstractThe transformations of colloidal semiconductor magic‐size clusters (MSCs) are expected to occur with only discrete, step‐wise redshifts in optical absorption. Here, we challenge this assumption presenting a novel, conceptually different transformation, for which the redshift is continuous. In the room‐temperature transformation from CdTe MSC‐448 to MSC‐488 (designated by the peak wavelengths in nanometer), the redshift of absorption monitored in situ displays distinctly continuous and/or step‐wise behavior. Based on conclusive evidence provided by real‐time experiments, the former transformation is apparently direct and intra‐cluster with a relatively large energy barrier. The latter transformation is indirect and assisted by MSC precursor compounds (PCs). The former transformation follows the latter often, being predominant at a relatively high temperature. The present findings encourage a reconsideration of the absorption redshift reported previously for transformations of binary II–VI MSCs, together with the pathway associated without the increase of cluster mass.
Au20(tBu3P)8: Ein hochsymmetrischer metalloider Goldcluster in der Oxidationsstufe 0
Authors: Fetzer Florian , Pollard Nia , Michenfelder Nadine C. , Strienz Markus , Unterreiner Andreas N. , Clayborne Andre Z. , Schnepf Andreas 
Published: July 2022

AbstractMetalloide Goldcluster haben einzigartige Eigenschaften in Bezug auf ihre Größe und ihre Struktur und spielen eine Schlüsselrolle bei der Betrachtung des Übergangs von molekularer Verbindung zur Festkörperphase des jeweiligen Metalls. Im Folgenden wird die Synthese des ausschließlich von Phosphan‐Liganden stabilisierten metalloiden Goldclusters Au20(tBu3P)8beschrieben, in welchem alle Goldatome in der Oxidationsstufe null vorliegen. Die Einkristallstrukturanalyse ergab eine hochsymmetrische Anordnung der Goldatome als leeres Kuboktaeder, die der Festkörperstruktur von Gold ähnelt. Quantenchemische Rechnungen ergaben, dass der Cluster als 20‐Elektronen Superatom beschrieben werden kann. Die optischen Eigenschaften des Clusters zeigen molekülähnliches Verhalten.
Gauging Radical Stabilization with Carbenes
Authors: Breitwieser Kevin , Bahmann Hilke , Weiss Robert , Munz Dominik 
Published: July 2022

AbstractCarbenes, includingN‐heterocyclic carbene (NHC) ligands, are used extensively to stabilize open‐shell transition metal complexes and organic radicals. Yet, it remains unknown, which carbene stabilizes a radical well and, thus, how to design radical‐stabilizing C‐donor ligands. With the large variety of C‐donor ligands experimentally investigated and their electronic properties established, we report herein their radical‐stabilizing effect. We show that radical stabilization can be understood by a captodative frontier orbital description involving π‐donation to‐ and π‐donation from the carbenes. This picture sheds a new perspective on NHC chemistry, where π‐donor effects usually are assumed to be negligible. Further, it allows for the intuitive prediction of the thermodynamic stability of covalent radicals of main group‐ and transition metal carbene complexes, and the quantification of redox non‐innocence.
Energy‐Transfer Photocatalysis Using Lead Halide Perovskite Nanocrystals: Sensitizing Molecular Isomerization and Cycloaddition
Authors: Liu Meng , Xia Pan , Zhao Guohui , Nie Chengming , Gao Kaimin , He Shan , Wang Lifeng , Wu Kaifeng 
Published: July 2022

AbstractA relatively new addition to the application portfolio of lead halide perovskites is to photosensitize molecular triplets for a variety of photochemical applications. Here we report visible‐light‐driven isomerization and cycloaddition of organic molecules sensitized by spectrally‐tunable perovskite nanocrystals. We first demonstrate with stilbene as the substrate molecule that photoisomerization can proceed efficiently and rapidly by either directly grafting carboxylated stilbene onto nanocrystal surfaces or using triplet–acceptor ligands as the energy relay. The relay approach is more generally applicable as it does not require anchoring‐group functionalization of substrate molecules, allowing us to facilely extend it to isomerization of a series of substituted stilbene molecules and ring‐closing isomerization of diarylethene, as well as intermolecular [2+2] cycloaddition of acenaphthylene. This study opens an avenue of energy‐transfer photocatalysis using perovskite nanocrystals.
A Molecular “A‐Type” Tangled Metallocube
Authors: Ma Li‐Li , Li Yang , Li Xin , Zhang Le , Sun Li‐Ying , Han Ying‐Feng 
Published: July 2022

AbstractTangled cubes feature the topology of typical Platonic cubes, with their “faces” traversed by edges in different ways. This study generates an “A‐type” tangled metallocube from the reaction of binuclear gold‐NHC complex and H2S. The tangled cube topology was validated by multinuclear nuclear magnetic resonance (NMR) spectroscopy, high‐resolution electrospray‐ionization (HR‐ESI) mass spectrometry, and single‐crystal X‐ray diffraction analysis. This study offers a simple and effective approach to designing and fabricating new, topologically unique molecular structures.