bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fluorescent Carbon Dots: Fantastic Electroluminescent Materials for Light‐Emitting Diodes
Authors: Zhao Biao , Tan Zhan'ao 
Published: February 2021

AbstractFluorescent carbon dots (CDs) have emerged as fantastic luminescent nanomaterials with significant potentials on account of their unique photoluminescence properties, high stability, and low toxicity. The application of CDs in electroluminescent light‐emitting diodes (LEDs) have aroused much interest in recent years. Herein, the state‐of‐the‐art advances of CD‐based electroluminescent LEDs are summarized, in which CDs act as active emission layer and interface transport layer materials is discussed and highlighted. Besides, the device structure of CD‐based LEDs and preparation methods of CDs are also introduced. Furthermore, the opportunities and challenges for achieving high performance CD‐based electroluminescent LED devices are presented. This review article is expected to stimulate more unprecedented achievements derived from CDs and CD‐based electroluminescent LEDs, thus further promoting their practical applications in future solid‐state lighting and flat‐panel displays.
Engineering Textile Electrode and Bacterial Cellulose Nanofiber Reinforced Hydrogel Electrolyte to Enable High‐Performance Flexible All‐Solid‐State Supercapacitors
Authors: Li Xiaolong , Yuan Libei , Liu Rong , He Hanna , Hao Junnan , Lu Yan , Wang Yuanming , Liang Gemeng , Yuan Guohui , Guo Zaiping 
Published: February 2021

AbstractThe fabrication of highly durable, flexible, all‐solid‐state supercapacitors (ASCs) remains challenging because of the unavoidable mechanical stress that such devices are subjected to in wearable applications. Natural/artificial fiber textiles are regarded as prospective materials for flexible ASCs due to their outstanding physicochemical properties. Here, a high‐performance ASC is designed by employing graphene‐encapsulated polyester fiber loaded with polyaniline as the flexible electrodes and bacterial cellulose (BC) nanofiber‐reinforced polyacrylamide as the hydrogel electrolyte. The ASC combines the textile electrode capable of arbitrary deformation with the BC‐reinforced hydrogel with high ionic conductivity (125 mS cm−1), high tensile strength (330 kPa), and superelasticity (stretchability up to ≈1300%), giving rise to a device with high stability/compatibility between the electrodes and electrolyte that is compliant with flexible electronics. As a result, this ASC delivers high areal capacitance of 564 mF cm−2, excellent rate capability, good energy/power densities, and more importantly, superior mechanical properties without significant capacitance degradation after repeated bending, confirming the functionality of the ASC under mechanical deformation. This work demonstrates an effective design for a sufficiently tough energy storage device, which shows great potential in truly wearable applications.
Mesoporous Thorn‐Covered Core–Shell Cathode and 3D Reduced Graphene Oxide Aerogel Composite Anode with Conductive Multivalence Metal Sulfides for High‐Performance Aqueous Hybrid Capacitors
Authors: Park Min Gyu , Choi Jae Won , Ock Il Woo , Kim Gi Hwan , Kang Jeung Ku 
Published: February 2021

AbstractAqueous hybrid capacitors (AHCs) are very promising electrochemical energy devices due to their being safe, cheap, and environmentally friendly, but their low energy and power densities are yet to be overcome for prolonged operation in a single fast charging device. Herein, a strategy to realize high‐energy density and ultrafast rechargeable AHCs is reported. A thorn‐covered core–shell conductive multivalence metal sulfide is synthesized as a cathode material that achieves high capacity via multivalence Ni and Co states and contains multiple mesoporous channels for fast ion transfer and ultrafine nanoparticles for efficient contact with electrolyte ions. Moreover, the multivalence metal states of the Fe1−xS anode units loaded on a three‐dimensional carbon structure with the mesoporous holes attain high capacity even at a very fast charging rate (20 A g−1, ≈86.4 C rate). The proposed AHC exploits the advantages of capacitive and diffusion‐controlled reactions. This is demonstrated by its high‐energy density (up to 120.5 Wh kg−1) surpassing that of state‐of‐the‐art AHCs and the ultrafast rechargeable power density (up to 23,998 W kg−1) that exceeds those of battery‐type reactions more than 100‐fold and provides long‐life stability for over 50 000 charge–discharge cycles.
Three Digital Agriculture Problems in Cotton Solved by Distributed Ledger Technology
Authors: Griffin Terry W. , Harris Keith D. , Ward Jason K. , Goeringer Paul , Richard Jessica A. 
Published: February 2021

AbstractDistributed ledger technology applied to Big Data in agriculture presents challenges and opportunities. Opportunities exist to solve decades‐old farm data management problems. Real‐world examples of applying distributed ledger technology to current farm data problems in cotton include (1) yield monitor data quality assurance, (2) sustainability metrics and resource tracking of cotton lint quality data from ginner back to subfield locations, and (3) increasing supply chain coordination by providing more information to warehouse managers. The culmination of the discussion across three aspects of cotton production data is of interest to farmers, researchers, policy makers, and consumers.
Research environment and resources to support pediatric emergency medicine fellow research
Authors: DesPain Angelica W. , Gutman Colleen K. , Cruz Andrea T. , Aronson Paul L. , Chamberlain James M. , Chang Todd P. , Florin Todd A. , Kaplan Ron L. , Nigrovic Lise E. , Pruitt Christopher M. , Thompson Amy D. , Gonzalez Victor M. , Mistry Rakesh D. 
Published: February 2021

AbstractBackgroundThere is a need for pediatric emergency medicine (PEM) researchers, but the current state of PEM fellow research training is not well described. We sought to (1) describe resources and gaps in PEM fellowship research training and (2) assess agreement between fellow and program director (PD) perceptions of these in fellow research experience.MethodsSurveys were distributed electronically to U.S. PEM fellows and PDs from March to April 2020. Fellows and PDs were queried on program research infrastructure and current gaps in fellow research experience. For programs that had at least one fellow and PD response, each fellow response was compared to their PD’s corresponding response (reference standard). For each binary survey item, we determined the percent of responses with agreement between the fellow and PD.ResultsOf 79 fellowship programs, 70 (89%) were represented with at least one response, including responses from 59 PDs (75%) and 218 fellows (39% of all fellows, representing 80% of programs). Fellows and PDs identified mentorship and faculty engagement as the most important needs for successful fellowship research; for every one fellow there was a median of 0.8 potential faculty mentors in the division. Twenty percent of fellows were not satisfied with mentorship opportunities. There was no association between fellow career research intent (high, defined as ≥20% dedicated time, or low) with current year of training (p = 0.88), program size (p = 0.67), and area of research focus (p = 0.40). Fellows were often unaware of research being performed by division faculty.ConclusionPEM fellows were not consistently aware of resources available to support research training. To better support PEM fellows’ research training, many programs may need to expand mentorship and increase fellows’ awareness of local and external resources and opportunities.
Association among length of residence, physical activity, and obesity in the US immigrants: A regression‐based mediation analysis
Authors: Jung Myungjin , Kim Heontae , Loprinzi Paul D. , Kang Minsoo 
Published: February 2021

AbstractObjectivesTo examine the mediated relationship between objectively measured obesity, accelerometer‐based moderate‐to‐vigorous physical activity (MVPA), and length of residence among US immigrants.MethodsA total of 885 adults (≥18 years) who were born outside the United States from the 2003 to 2006 National Health and Nutrition Examination Survey were included in the analysis. The participants were categorized into two groups (i.e., living in the United States ≥15 years vs. <15 years). MVPA time (minutes/day) was measured by ActiGraph accelerometry. Obesity was defined as body fat percentage measured by dual‐energy X‐ray absorptiometry. Regression‐based mediation analysis was conducted using SURVEY procedures in SAS version 9.4.ResultsWhen controlling for covariates, immigrants living in the United States for ≥15 years were significantly less likely to spend time participating in MVPA (c;β = −4.50,p = .04), and more likely to be at high risk of obesity (a;β = 1.70,p = .01) compared to those living in the United States for <15 years. Also, the relationship between obesity and MVPA was statistically significant (b;β = −0.80,p = .003). Length of residence was indirectly associated with MVPA (ab;β = −1.37,p = .03), suggesting that obesity mediated the association of length of residence on MVPA (c';β = −3.13,p = .20).ConclusionsObesity mediated the association between length of residence and MVPA in the US immigrants. These findings may encourage long‐term US immigrants to prevent and treat obesity for increasing the amount of MVPA time.
Progress in Photoinduced Radical Reactions using Electron Donor‐Acceptor Complexes
Authors: Zheng Lvyin , Cai Liuhuan , Tao Kailiang , Xie Zhen , Lai Yin‐Long , Guo Wei 
Published: February 2021

AbstractPhotocatalyzed organic synthesis transformation is a remarkable green synthetic strategy because of the advantages of operational simplicity, high chemoselectivities, cheap, and environmental benignancy, along with the extensive applications in the fields of organic, pharmaceutical and functional material chemistry. Generally, photoredox catalysts or photosensitizers are necessary for the generation of their excited states to perform the successive oxidative or reductive reactions through the single electron transfer (SET) or energy transfer (ET) process. Furthermore, the exploration of a colored electron donor‐acceptor (EDA) complex or a charge transfer (CT) complex between an electron‐rich and an electron‐poor substrate provides the chance to deliver the excited intermediate under the irradiation of light, resulting in the formation of radical activate species through a single electron transfer to induce successive various radical reactions. These reactions were performed without the need of any external photocatalysts under mild reaction conditions. Herein, this review focuses on the recent progress on photoinduced radical addition reactions, radical borylations, reductive reactions, radical‐radical cross‐coupling reactions, degradation reactions and radical cascade cyclization via EDA complexes. We highlight these novel green synthetic methodologies and applications, as well as the mechanisms. This review will help to provide references for organic and medicinal chemists who are charmed by these green organic photochemical transformations based on EDA complexes.
Palladium Nanocatalysts for Cascade C−N Cross‐Coupling/Heck Reaction
Authors: Rodriguez‐Oliva Ivan , Losada‐Garcia Noelia , Santos A. Sofia , Marques M. Manuel B. , Palomo Jose M. 
Published: February 2021

AbstractHighly stable nanocatalysts have been synthesized in aqueous medium at room temperature by thein situformation of Pd nanoparticles (PdNPs) embedded in an enzyme net. Different parameters in the synthesis were evaluated such as T, ratio enzyme/Pd salt, usingCandida antarctica Blipase (CALB) as enzyme. In all different CALB/PdNPs hybrids synthesized, crystalline Pd(0) as a unique metallic species was confirmed by XRD. Spherical nanoparticles were obtained with diameter size from 2 to 11 nm, depending on the synthetic conditions. These CALB/PdNPs hybrids were employed as catalyst in the C−N/Heck reaction cross‐coupling cascade for the synthesis of substituted azaindoles using various amino‐o‐bromopyridines as starting material in moderate conditions. The best conversion with high selectivity of the formation of C2‐substituted azaindoles was obtained at 90 °C using dioxane containing 5% water as the best reaction solvent from the different solvents tested, using potassium carbonate as milder base. The catalysis with these CALB/PdNPs hybrids at these conditions was also successful in the production of several isomers of azaindoles, especially relevant for the formation of the 7‐ azaindole, where 65% conversion was obtained, a very good improvement when compared to the reported protocol using a Pd2(dba)3/XPhos/t‐BuONa catalytic system.
Behavioral and physiological responses to instability in group membership in wild male woolly monkeys (Lagothrix lagotricha poeppigii)
Authors: Pain Evelyn L. , Koenig Andreas , Di Fiore Anthony , Lu Amy 
Published: February 2021

AbstractIn group‐living species, integrating into a new social group after dispersal is an important life history milestone associated with physical and social challenges. Generally, this process seems to be accompanied by heightened glucocorticoid (GC) concentrations; however, most studies of physiological responses to group transfer have been conducted on species with despotic social relationships, where integrating individuals are often targets of frequent aggression. Here we present data on fecal glucocorticoid (fGC) concentrations during periods of unstable group membership for male woolly monkeys (Lagothrix lagotricha poeppigii), a species with extremely low rates of male–male aggression and generally tolerant male–male associations. We collected data on males in four study groups at the Tiputini Biodiversity Station, Ecuador, and observed three attempted transfer events, involving a total of four adult males, in one study group. We observed only three instances of overt aggression (chases) between males across the entire study period, though male display behaviors were more frequent. We tested whether rates of displays were higher during periods of unstable group membership using a generalized linear mixed model (LMM). We also examined whether male status, group stability, and the occurrence of intergroup encounters affected fGC concentrations using LMMs. Contrary to our predictions, rates of display behaviors were not higher during periods of unstable group membership. However, both transient/integrating males and those who were already group members showed elevated fGC concentrations during these unstable periods. Our results suggest that even in species with tolerant male–male relationships, the integration of unfamiliar individuals can provoke an increase in GCs.
COVID‐19 and dementia: Analyses of risk, disparity, and outcomes from electronic health records in the US
Authors: Wang QuanQiu , Davis Pamela B. , Gurney Mark E. , Xu Rong 
Published: February 2021

AbstractIntroductionAt present, there is limited data on the risks, disparity, and outcomes for COVID‐19 in patients with dementia in the United States.MethodsThis is a retrospective case‐control analysis of patient electronic health records (EHRs) of 61.9 million adult and senior patients (age ≥ 18 years) in the United States up to August 21, 2020.ResultsPatients with dementia were at increased risk for COVID‐19 compared to patients without dementia (adjusted odds ratio [AOR]: 2.00 [95% confidence interval (CI), 1.94–2.06], P < .001), with the strongest effect for vascular dementia (AOR: 3.17 [95% CI, 2.97–3.37], P < .001), followed by presenile dementia (AOR: 2.62 [95% CI, 2.28–3.00], P < .001), Alzheimer's disease (AOR: 1.86 [95% CI, 1.77–1.96], P < .001), senile dementia (AOR: 1.99 [95% CI, 1.86–2.13], P < .001) and post‐traumatic dementia (AOR: 1.67 [95% CI, 1.51–1.86] P < .001). Blacks with dementia had higher risk of COVID‐19 than Whites (AOR: 2.86 [95% CI, 2.67–3.06], P < .001). The 6‐month mortality and hospitalization risks in patients with dementia and COVID‐19 were 20.99% and 59.26%, respectively.DiscussionThese findings highlight the need to protect patients with dementia as part of the strategy to control the COVID‐19 pandemic.
Radical‐Pairing Interactions in a Molecular Switch Evidenced by Ion Mobility Spectrometry and Infrared Ion Spectroscopy
Authors: Hanozin Emeline , Mignolet Benoit , Martens Jonathan , Berden Giel , Sluysmans Damien , Duwez Anne‐Sophie , Stoddart J. Fraser , Eppe Gauthier , Oomens Jos , De Pauw Edwin , Morsa Denis 
Published: February 2021

AbstractThe digital revolution sets a milestone in the progressive miniaturization of working devices and in the underlying advent of molecular machines. Foldamers involving mechanically entangled components with modular secondary structures are among the most promising designs for molecular switch‐based applications. Characterizing the nature and dynamics of their intramolecular network following the application of a stimulus is the key to their performance. Here, we use non‐dissociative electron transfer as a reductive stimulus in the gas phase and probe the consecutive co‐conformational transitions of a donor‐acceptor oligorotaxane foldamer using electrospray mass spectrometry interfaced with ion mobility and infrared ion spectroscopy. A comparison of collision cross section distributions for analogous closed‐shell and radical molecular ions sheds light on their respective formation energetics, while variations in their respective infrared absorption bands evidence changes in intramolecular organization as the foldamer becomes more compact. These differences are compatible with the advent of radical‐pairing interactions.
Single‐Stranded DNA as Supramolecular Template for One‐Dimensional Palladium(II) Arrays
Authors: Pérez‐Romero Antonio , Domínguez‐Martín Alicia , Galli Simona , Santamaría‐Díaz Noelia , Palacios Oscar , Dobado José A. , Nyman May , Galindo Miguel A. 
Published: February 2021

AbstractAtomic‐level control over the position and growth of a single and continuous metal chain is an ambitious goal that often requires complex and costly processes. Herein, we demonstrate that 1Pd‐DNA molecules, comprising a continuous single chain of PdII ions, can be prepared by a simple self‐assembly reaction between the complex [Pd(Cheld)(CH3CN)] (1Pd_CH3CN) (Cheld=chelidamic acid) and single‐stranded DNA homopolymers (ss‐DNA) containing adenine (A) or 7‐deazaadenine (X) bases. The single PdII‐base pairs [1Pd(N1‐A)] and [1Pd(N1‐X)] were synthesized and characterized in solution and solid‐state (X‐ray diffraction) revealing an arrangement similar to that of natural Watson–Crick base pairs. Subsequently, 1Pd‐DNA hybrids were prepared, characterized, and their structures studied by small‐angle X‐ray scattering (SAXS) and ab‐initio calculations. The results indicate that the 1Pd‐DNA structures resemble that of double‐stranded DNA, with one strand being replaced by a supramolecular stack of continuous PdII complexes.
AIE‐Active Chiral [3]Rotaxanes with Switchable Circularly Polarized Luminescence
Authors: Li Wei‐Jian , Gu Qingyi , Wang Xu‐Qing , Zhang Dan‐Yang , Wang Yu‐Te , He Xiao , Wang Wei , Yang Hai‐Bo 
Published: February 2021

AbstractThe construction of circularly polarized luminescence (CPL) switches with multiple switchable emission states and high dissymmetry factors (glum) has attracted increasing attention due to their broad applications in diverse fields such as the development of smart devices and sensors. Herein, a new family of AIE‐active chiral [3]rotaxanes were designed and synthesized, from which a novel CPL switching system was successfully constructed. The switching process was realized through the controlled motions of the chiral pillar[5]arene macrocycles along the axle through the addition or removal of the acetate anions, which not only modulated the chirality information transfer but also tuned the aggregations of the integrated [3]rotaxanes, thus resulting in reversible transformations between two emission states with both high photoluminescence quantum yields (PLQYs) and high dissymmetry factors (glum) values.
Twin Pathways: Discerning the Origins of Multiply Twinned Colloidal Nanoparticles
Authors: Du Jingshan S. , Zhou Wenjie , Rupich Sara M. , Mirkin Chad A. 
Published: February 2021

AbstractThe structure of multiply twinned particles (MTPs) provides an example of how specific crystallographic features dictate the geometric shape of finite‐sized crystals. The formation of MTPs during colloidal synthesis can occur through at least two different pathways: 1) growth from multiply twinned seeds or 2) the stepwise formation of new twin boundaries on single‐crystalline seeds (either by particle overgrowth or multiparticle attachment). By utilizing in situ transmission electron microscopy, recent studies have provided real‐time evidence for both pathways. Looking forward, the knowledge of specific evolution pathways that occur under a given synthetic condition will aid in the design of robust MTP syntheses. More importantly, further studies pertaining to the structural evolution and energetics of nanoparticles are needed to provide a complete understanding of MTP formation pathways.
Lewis Acid Strength of Interfacial Metal Sites Drives CH3OH Selectivity and Formation Rates on Cu‐Based CO2 Hydrogenation Catalysts
Authors: Noh Gina , Lam Erwin , Bregante Daniel T. , Meyet Jordan , Šot Petr , Flaherty David W. , Copéret Christophe 
Published: February 2021

AbstractCH3OH formation rates in CO2 hydrogenation on Cu‐based catalysts sensitively depend on the nature of the support and the presence of promoters. In this context, Cu nanoparticles supported on tailored supports (highly dispersed M on SiO2; M=Ti, Zr, Hf, Nb, Ta) were prepared via surface organometallic chemistry, and their catalytic performance was systematically investigated for CO2 hydrogenation to CH3OH. The presence of Lewis acid sites enhances CH3OH formation rate, likely originating from stabilization of formate and methoxy surface intermediates at the periphery of Cu nanoparticles, as evidenced by metrics of Lewis acid strength and detection of surface intermediates. The stabilization of surface intermediates depends on the strength of Lewis acid M sites, described by pyridine adsorption enthalpies and 13C chemical shifts of ‐OCH3 coordinated to M; these chemical shifts are demonstrated here to be a molecular descriptor for Lewis acid strength and reactivity in CO2 hydrogenation.
Application of blocked isocyanate in preparation of polyurethane(urea) elastomers
Authors: Sang Shilin , Li Yuanyuan , Wang Kaijie , Tang Jialing 
Published: February 2021

AbstractHigh‐performance casting polyurethane elastomers (CPUe) were successfully synthesized by the reaction of polyurethane prepolymer (PUP) blocked by methyl ethyl ketone oxime (MEKO) with diamine chain extenders. The effects of blocking agent were systematically studied on the structures, thermal stabilities, mechanical properties, and processability of polyurethane. The addition of MEKO significantly improved the tensile strength and toughness. The maximum tensile strength was 35.6 MPa, and the maximum elongation at break was 1065%. The high strength and toughness were attributed to the fact that under mild reaction conditions, the reaction tended to extend the molecular chains, which indicated that the formation of long chains was conducive to the extension and self‐reinforcement of chain segments. Crystallization and strong hydrogen bonds between molecules also led to low loss factor. This deblocking polymerization strategy solves the gel problem in the polymerization process, and provides a new idea for the preparation of CPU.