bluuebunny/crossref_metadata_2025_split huggingface dataset:
4D Printed Light‐Responsive Patterned Liquid Crystal Elastomer Actuators Using a Single Structural Color Ink
Authors: Sol Jeroen A. H. P. , Douma Robin F. , Schenning Albert P. H. J. , Debije Michael G. 
Published: October 2022

AbstractEnvisioning robotic devices with functionality resulting from processing rather than exclusively material composition, multimodal responsive devices produced from a single azobenzene‐functionalized cholesteric liquid crystal elastomer ink are demonstrated. The resulting device displays simultaneous structural color and actuation in response to both ultraviolet and blue light exposures. Through direct ink writing, a microextrusion‐based additive manufacturing technique, the liquid crystalline ink is deposited into different effective mesophases—planar and slanted cholesteric, and a uniaxial pseudo‐nematic state—by altering only two printing conditions: deposition speed and time before photopolymerization. Comparing the three different printed mesophases, marked differences in optical properties and actuation behaviors are found. Demonstrators based on bilayer architectures present concepts for interactive soft multiactuators deposited in a single printing step from a single ink.
Enhancements of Second Harmonic Generation and Birefringence in Traditional RbTiOPO4‐Type Crystals by Aliovalent Substitution of Ti Site
Authors: Zhu Pengfei , Li Ziqing , Wang Zhenyan , Ai Li , Zhao Jianfu , Li Chao , Duan Xiulan , Zhao Xian , Yu Fapeng 
Published: October 2022

AbstractStrong second harmonic response and large birefringence of nonlinear optical (NLO) materials have important scientific and technical significance for tunable lasers. The second harmonic generation (SHG) response in NLO crystals has been generally enhanced by improving the polarization of bridged oxygen atoms or local structural distortions, while the synergy of the two contributions to enhance the SHG response is rarely explored. To this end, new crystals with traditional RbTiOPO4 (RTP)‐structure, Rb1–xTi1–xSbxOPO4 (x = 0.01, 0.03, and 0.06), containing novel functional SbO6 octahedra and Rb vacancies are designed through a one‐site aliovalent substitution and grown in this work. Rb0.94Ti0.94Sb0.06OPO4 exhibits an enhanced SHG response, nearly 1.48 times that of the RTP crystal, accompanied by the largest birefringence in phosphates (exp. 0.202 at 546 nm, cal. 0.156 at 1064 nm). Theoretical calculations and crystal structure analysis confirm that the higher polarizability of bridged oxygen and the local structural distortions in Rb1–xTi1–xSbxOPO4 strengthen the NLO activity of neighboring units, thus significantly prompt the SHG effect and optical anisotropy. This study provides a new paradigm to deeply improve the NLO performance of crystal materials and benefits for expanding their practical applications.
Erbium‐Hyperdoped Silicon Quantum Dots: A Platform of Ratiometric Near‐Infrared Fluorescence
Authors: Wang Kun , He Qiang , Yang Deren , Pi Xiaodong 
Published: October 2022

AbstractRatiometric near‐infrared (NIR) fluorescence holds great promise for important applications such as temperature sensing, food safety detection, and biological imaging owing to its self‐calibration and contactless measurements in the NIR region. For ratiometric NIR fluorescence, the suppression of optical reabsorption and signal interference is crucial. In this work, freestanding erbium (Er)‐hyperdoped silicon quantum dots (Si QDs) with UV absorption and NIR emission are synthesized via nonthermal plasma, effectively avoiding optical reabsorption. Er with the valence of +3 is found to be mainly located in the subsurface region of Er‐hyperdoped Si QDs, which emit NIR light at the wavelengths of 830 and 1540 nm. The distinct difference between the two NIR wavelengths (Δλ = 710 nm) well impedes signal interference in ratiometric NIR fluorescence. It is shown that Er‐hyperdoped Si QDs may be a powerful platform of ratiometric NIR fluorescence by exemplarily demonstrating their temperature‐sensing capability in a wide temperature range (297–477 K) with high relative sensitivity (3.05% K−1), high‐temperature resolution (<0.018 K), and high repeatability (>98%). The temperature sensing of Er‐hyperdoped Si QDs may be further employed to construct logic gates, enabling in‐sensor computing.
Synthesis of Phenanthrene‐Based Polycycles by Gold(I)‐Catalyzed Cyclization of Biphenyl‐Embedded Trienynes
Authors: Milián Ana , García‐García Patricia , Vaquero Juan J. , Sanz Roberto , Fernández‐Rodríguez Manuel A. 
Published: October 2022

AbstractGold(I)‐catalyzed cyclization of o‐alkenyl‐o’‐alkynylbiaryls in the presence of external or internal nucleophiles provides a straightforward access to phenanthrene‐based polycycles, which are of considerable interest in materials science. Thus, their reactions with alcohols yield functionalized dihydrophenanthrenes, in a process that can also be carried out intramolecularly, to provide phenanthrene‐derived heteropolycyclic compounds. Moreover, benzo[b]triphenylenes can be synthesized from o‐methoxyvinyl‐o’‐alkynylbiaryls, in a reaction in which an (hetero)aryl substituent at the triple bond acts as an internal nucleophile.magnified image
Unexpected Stereoselective Access to 2‐Aminooxazolines from Propargyl Ureas by Silver Salts under Mild Conditions
Authors: Voronov Aleksandr , Casnati Alessandra , Mazzeo Paolo P. , Pelagatti Paolo , Bacchi Alessia , Mancuso Raffaella , Gabriele Bartolo , Motti Elena , Maestri Giovanni , Fehér Péter Pál , Stirling András , Della Ca' Nicola 
Published: October 2022

AbstractPropargyl ureas can lead to a range of possible heterocyclic compounds, mainly depending on the employed catalyst. Silver salts are known to promote the N‐5‐exo‐dig cyclization mode to imidazolidinone derivatives. Conversely, a versatile and stereoselective O‐5‐exo‐dig cyclization of propargyl ureas to 2‐aminooxazolines by Ag(I) catalysis is here disclosed. Good to excellent yields and complete stereoselectivity of the external double bond have been achieved under milder reaction conditions (50–60 °C). A one‐pot protocol starting from the corresponding propargylic amines and isocyanates has been developed as well. N,N’‐Dipropargyl ureas underwent a uncommon O‐5‐exo‐dig/N‐5‐endo‐dig double cyclization sequence. Finally, insights into the tautomeric equilibrium of 2‐aminooxazoles and on their relative reactivity are provided.magnified image
Magnetic Skin for Touchless Human–Computer Interaction to Prevent Healthcare‐Associated Infections
Authors: Zhang Junjie , Chen Guangyuan , Chen Jiamin 
Published: October 2022

AbstractHealthcare‐associated infections are a major problem in hospitals, and regular disinfection methods cannot guarantee that all pathogens are eliminated. Non‐contact human–computer interactions can effectively reduce the risk of contamination by preventing direct contact between medical staff and electronic products. In this study, a new type of flexible and highly malleable magnetic skin composed of a mixture of an elastic matrix and permanent magnetic powder is demonstrated. In addition, the relationship between the magnetic skin properties and the elastic matrix, magnetic powder material, and their ratio is studied. In addition, the application of magnetic skin in gesture recognition (representing discrete gesture input) and magnetic positioning (representing continuous input) is explored to easily achieve touchless human–computer interactions. Both perform well and provide a new way for future human–computer interaction.
Gradients of Orientation, Composition, and Hydration of Proteins for Efficient Light Collection by the Cornea of the Horseshoe Crab
Authors: Spaeker Oliver , Taylor Gavin J. , Wilts Bodo D. , Slabý Tomáš , Abdel‐Rahman Mohamed Ashraf Khalil , Scoppola Ernesto , Schmitt Clemens N. Z. , Sztucki Michael , Liu Jiliang , Bertinetti Luca , Wagermaier Wolfgang , Scholtz Gerhard , Fratzl Peter , Politi Yael 
Published: October 2022

AbstractThe lateral eyes of the horseshoe crab, Limulus polyphemus, are the largest compound eyes within recent Arthropoda. The cornea of these eyes contains hundreds of inward projecting elongated cuticular cones and concentrate light onto proximal photoreceptor cells. Although this visual system has been extensively studied before, the precise mechanism allowing vision has remained controversial. Correlating high‐resolution quantitative refractive index (RI) mapping and structural analysis, it is demonstrated how gradients of RI in the cornea stem from structural and compositional gradients in the cornea. In particular, these RI variations result from the chitin‐protein fibers architecture, heterogeneity in protein composition, and bromine doping, as well as spatial variation in water content resulting from matrix cross‐linking on the one hand and cuticle porosity on the other hand. Combining the realistic cornea structure and measured RI gradients with full‐wave optical modeling and ray tracing, it is revealed that the light collection mechanism switches from refraction‐based graded index (GRIN) optics at normal light incidence to combined GRIN and total internal reflection mechanism at high incident angles. The optical properties of the cornea are governed by different mechanisms at different hierarchical levels, demonstrating the remarkable versatility of arthropod cuticle.
Photo‐Facilitated Detection and Sequencing of 5‐Formylcytidine RNA
Authors: Jin Xiao‐Yang , Huang Zu‐Rui , Xie Li‐Jun , Liu Li , Han Da‐Li , Cheng Liang 
Published: October 2022

Abstract5‐Formylcytidine (f5C) is one of the epigenetic nucleotides in tRNA. Despite the evident importance of f5C in gene expression regulation, little is known about its exact amount and position. To capture this information, we developed a modification‐specific functionalization with a semi‐stabilized ylide. The chemical labelling exhibited a high selectivity towards f5C and allowed distinction from similar 5‐formyluridine. We realized a detection strategy based on the fluorescence signal of the cyclization product 4,5‐pyridin‐2‐amine‐cytidine paC, which exhibited a high quantum yield. The results clearly identified f5C with a limit of detection at 0.58 nM. This method altered the hydrogen bonding activities of f5C and modulated its reverse transcription signature in its sequencing profile. We showed that f5C can be detected from tRNA segments with a single‐base resolution. Taken together, this approach is a sensitive, antibody‐free, and applicable detection and sequencing method for f5C‐containing RNA.
Overcoming Electrostatic Interaction via Strong Complexation for Highly Selective Reduction of CN− into N2
Authors: Tian Lei , Zhang Long‐Shuai , Zheng Ling‐Ling , Chen Ying , Ding Lin , Fan Jie‐Ping , Wu Dai‐She , Zou Jian‐Ping , Luo Sheng‐Lian 
Published: October 2022

AbstractLimited by the electrostatic interaction, the oxidation reaction of cations at the anode and the reduction reaction of anions at the cathode in the electrocatalytic system nearly cannot be achieved. This study proposes a novel strategy to overcome electrostatic interaction via strong complexation, realizing the electrocatalytic reduction of cyanide (CN−) at the cathode and then converting the generated reduction products into nitrogen (N2) at the anode. Theoretical calculations and experimental results confirm that the polarization of the transition metal oxide cathodes under the electric field causes the strong chemisorption between CN− and cathode, inducing the preferential enrichment of CN− to the cathode. CN− is hydrogenated by atomic hydrogen at the cathode to methylamine/ammonia, which are further oxidized into N2 by free chlorine derived from the anode. This paper provides a new idea for realizing the unconventional and unrealizable reactions in the electrocatalytic system.
Umpolung Synthesis of Pyridyl Ethers by BiV‐Mediated O‐Arylation of Pyridones
Authors: Ruffell Katie , Gallegos Liliana C. , Ling Kenneth B. , Paton Robert S. , Ball Liam T. 
Published: October 2022

AbstractWe report that O‐selective arylation of 2‐ and 4‐pyridones with arylboronic acids is affected by a modular, bismacycle‐based system. The utility of this umpolung approach to pyridyl ethers, which is complementary to conventional methods based on SNAr or cross‐coupling, is demonstrated through the concise synthesis of Ki6783 and picolinafen, and the formal synthesis of cabozantib and golvatinib. Computational investigations reveal that arylation proceeds in a concerted fashion via a 5‐membered transition state. The kinetically‐controlled regioselectivity for O‐arylation—which is reversed relative to previous BiV‐mediated pyridone arylations—is attributed primarily to the geometric constraints imposed by the bismacyclic scaffold.
Multiple Roles of Alkanethiolate‐Ligands in Direct Formation of H2O2 over Pd Nanoparticles
Authors: Chen Lin , Moura Pedro , Medlin J. Will , Grönbeck Henrik 
Published: October 2022

AbstractCoadsorbed organic species including thiolates can promote direct synthesis of hydrogen peroxide from H2 and O2 over Pd particles. Here, density functional theory based kinetic modeling, augmented with activity measurements and vibrational spectroscopy are used to provide atomistic understanding of direct H2O2 formation over alkylthiolate(RS) Pd. We find that the RS species are oxidized during reaction conditions yielding RSO2 as the effective ligand. The RSO2 ligand shows superior ability for proton transfer to the intermediate surface species OOH, which accelerates the formation of H2O2. The ligands promote the selectivity also by blocking sites for unselective water formation and by modifying the electronic structure of Pd. The work rationalizes observations of enhanced selectivity of direct H2O2 formation over ligand‐funtionalized Pd nanoparticles and shows that engineering of organic surface modifiers can be used to promote desired hydrogen transfer routes.
Stereochemistry Controls Dihydrogen Bonding Strengths in Chiral Amine Boranes Adducts
Authors: Kemper Michael , Drost Deborah A. , Engelage Elric , Merten Christian 
Published: October 2022

AbstractThe growing interest in exploiting novel concepts of non‐covalent interactions in catalysts and supramolecular chemistry made us revisit a special kind of hydrogen bonding: the dihydrogen bond (DHB), formed between a classical hydrogen bond donor and a hydridic hydrogen as acceptor. Herein, we investigate how the strength of the N−Hδ+⋅⋅⋅δ−H−B interaction and hence the DHB‐driven self‐aggregation of amine‐borane adducts is governed by steric effects by comparing the structures and binding enthalpies of various chiral derivatives. For a diastereomeric pair of amine‐boranes prepared from a chiral secondary amine, we show that the stereochemistry at the nitrogen has significant influence on the interaction enthalpy. Based on this finding, N‐chiral amine boranes can be envisioned to become interesting building blocks in supramolecular chemistry to fine‐tune the formation dynamics of assemblies.
Features of the vertebral column and caudal fin skeleton for identifying Engraulis australis in food of the Australasian gannet Morus serrator, Hauraki Gulf, New Zealand
Authors: Jawad Laith A. , Adams Nigel J. 
Published: October 2022

AbstractIdentifying fish species from their bone remains is employed in identifying the prey of aquatic animals. However, diagnostic skeletal descriptions are scarce for fish species prey found in the food of piscivorous birds and other marine predators in New Zealand. The present article addresses this knowledge gap, providing a diagnostic description for the vertebral column and the skeleton of the caudal fin of the Australian anchovy Engraulis australis inhabiting coastal waters in and around the Hauraki Gulf, New Zealand. The vertebral column of E. australis is divided into four morphologically distinct regions more complicated than the classical division in abdominal and caudal parts only and the drawing of characteristic‐looking vertebral profiles. Each of these four regions is associated with characteristic vertebral profiles. These morphological descriptive parameters express a morphotype that may be linked with the swimming mode of the Australian anchovy. The skeleton of the caudal fin of E. australis showed distinctive characteristics that will be useful as diagnostic criteria to identify specimens of the Australian anchovy and separate them from the skeletal elements of other fish species found in the food of gannets and other marine predators in future studies.
A Flare Risk Index Informed by Select Immune Mediators in Systemic Lupus Erythematosus
Authors: Munroe Melissa E. , Blankenship Derek , DeFreese Daniele , Purushothaman Mohan , DeJager Wade , Macwana Susan , Guthridge Joel M. , Kamp Stan , Redinger Nancy , Aberle Teresa , Chakravarty Eliza F. , Arriens Cristina , Li Yanfeng , Zeng Hu , McCarthy‐Fruin Kathleen A. , Osei‐Onomahm Shirley‐Ann , Thanarajasingam Uma , James Judith A. , Jupe Eldon 
Published: October 2022

ObjectiveSystemic lupus erythematosus (SLE) is marked by immune dysregulation linked to varied clinical disease activity. Using a unique longitudinal cohort of SLE patients, this study sought to identify optimal immune mediators informing an empirically refined flare risk index (FRI) reflecting altered immunity prior to clinical disease flare.MethodsThirty‐seven SLE‐associated plasma mediators were evaluated by microfluidic immunoassay in 46 samples obtained in SLE patients with an imminent clinical disease flare (preflare) and 53 samples obtained in SLE patients without a flare over a corresponding period (pre‐nonflare). SLE patients were selected from a unique longitudinal cohort of 106 patients with classified SLE (meeting the American College of Rheumatology 1997 revised criteria for SLE or the Systemic Lupus International Collaborating Clinics 2012 revised criteria for SLE). Autoantibody specificities, hybrid SLE Disease Activity Index (hSLEDAI) scores, clinical features, and medication usage were also compared at preflare (mean ± SD 111 ± 47 days prior to flare) versus pre‐nonflare (99 ± 21 days prior to nonflare) time points. Variable importance was determined by random forest analysis with logistic regression subsequently applied to determine the optimal number and type of analytes informing a refined FRI.ResultsPreflare versus pre‐nonflare differences were not associated with demographics, autoantibody specificities, hSLEDAI scores, clinical features, nor medication usage. Forward selection and backward elimination of mediators ranked by variable importance resulted in 17 plasma mediator candidates differentiating preflare from pre‐nonflare visits. A final combination of 11 mediators best informed a newly refined FRI, which achieved a maximum sensitivity of 97% and maximum specificity of 98% after applying decision curve analysis to define low, medium, and high FRI scores.ConclusionWe verified altered immune mediators associated with imminent disease flare, and a subset of these mediators improved the FRI to identify SLE patients at risk of imminent flare. This molecularly informed, proactive management approach could be critical in prospective clinical trials and the clinical management of lupus.
Smart Multi‐Layer Architecture Electrodes for High Energy Density Lithium‐Ion Capacitors
Authors: Lee Sang Ho 
Published: October 2022

AbstractMulti‐layer architectures for use in both negative and positive electrodes are developed through a layer‐by‐layer spray printing approach using complementary material combinations, with the ultimate goal to realize an ideal concept of hybrid lithium‐ion capacitors more fully – delivering attractive energy densities of insertion‐type negative electrodes while preserving outstanding power performances of activated carbon positive electrodes. To sustain advantageous capacities of intercalation anodes even at ultra‐fast charging rates, a thin, discrete layer of high capacity Si was interleaved between high power Li4Ti5O12 electrodes. In a cathode electrode, a sequential layer of insertion‐type LiFePO4 was assembled with a conventional activated carbon layer into a single layer structure, aiming at boosting overall deliverable capacities. The lithium‐ion capacitor comprising the smart multi‐layer architectures of negative and positive electrodes then provided a remarkable energy density of ∼110 Wh/kg with an outstanding power performance of 15 kW/kg.
The effects of noncontingent reinforcement on task disengagement following failure of differential reinforcement treatment
Authors: O’Brien Matthew J. , Romani Patrick W. , Berg Wendy K. , Wacker David P. 
Published: October 2022

AbstractFollowing the failure of applications of differential reinforcement (DR), the effects of reinforcement delivered noncontingently (NCR) on task disengagement and task completion were evaluated within reversal designs for three children with autism spectrum disorder. In Experiment 1, we compared DR and NCR schedules that combined positive and negative reinforcement. In Experiment 2, we replicated the results of Experiment 1 and then evaluated NCR schedules composed solely of negative reinforcement and NCR schedules that combined negative reinforcement with high‐or low‐preferred stimuli. In Experiment 3, we further analyzed NCR schedules that included different types and qualities of positive reinforcement, but without the inclusion of negative reinforcement. The results showed that NCR schedules using positive reinforcers can be effective as a treatment for task disengagement, but the type and preference of the reinforcer can alter effectiveness. These results are interpreted in terms of the motivating operations associated with task disengagement.
Telehealth parent training for a young child at risk for autism spectrum disorder
Authors: Azzano Alicia , Vause Tricia , Ward Rebecca , Feldman Maurice A. 
Published: October 2022

AbstractThe global pandemic has highlighted the importance of telehealth to access behavioral interventions. Face‐to‐face parent training improves the development and behaviors of young children at risk for autism spectrum disorder (ASD). We evaluated a telehealth parent training intervention for a child at risk for ASD. Two parents identified possible early ASD symptoms in their 30‐month‐old son (lack of imitation, pointing, and vocal manding). Both parents simultaneously received telehealth behavioral skills training on the Parent Intervention for Children at Risk for Autism program for 1 hour per week over 29 weeks. Multiple baseline designs across parent and child behaviors showed that both parents improved their parent teaching fidelity above 80% and the child improved on all trained behaviors. This study expands the utility of telehealth behavioral parent training to young children at risk for ASD to mitigate early symptoms of ASD.