bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mechanically Robust, Elastic, and Healable Ionogels for Highly Sensitive Ultra‐Durable Ionic Skins
Authors: Li Tianqi , Wang Yuting , Li Siheng , Liu Xiaokong , Sun Junqi 
Published: June 2020

AbstractThe fabrication of highly durable skin‐mimicking sensors remains challenging because of the unavoidable fatigue and physical damage that sensors are subjected to in practical applications. In this study, ultra‐durable ionic skins (I‐skins) with excellent healability and high sensitivity are fabricated by impregnating ionic liquids (ILs) into a mechanically robust poly(urea‐urethane) (PU) network. The PU network is composed of crystallized poly(ε‐caprolactone) and flexible poly(ethylene glycol) that are dynamically cross‐linked with hindered urea bonds and hydrogen bonds. Such a design endows the resultant ionogels with high mechanical strength, good elasticity, Young's modulus similar to that of natural skin, and excellent healability. The ionogel‐based I‐skins exhibit a high sensitivity to a wide range of strains (0.1–300%) and pressures (0.1–20 kPa). Importantly, the I‐skins show a highly reproducible electrical response over 10 000 uninterrupted strain cycles. The sensing performance of the I‐skins stored in open air for 200 days is almost the same as that of the freshly prepared I‐skin. The fractured I‐skins can be easily healed by heating at 65 °C that restores their original ultra‐durable sensing performance. The long‐term durability of the I‐skins is attributed to the combination of non‐volatility of the ILs, excellent healability, and well‐designed mechanical properties.
Evaluation of strains of Beauveria bassiana and Isaria fumosorosea to control sugarcane aphids on grain sorghum
Authors: Harris‐Shultz Karen , Knoll Joseph , Punnuri Somashekhar , Niland Erika , Ni Xinzhi 
Published: June 2020

AbstractThe sugarcane aphid [Melanaphis sacchari (Zehntner)] has become a persistent problem to sorghum [Sorghum bicolor (L.) Moench] producers in the United States since its first identification on grain sorghum near Beaumont, TX, in 2013. Since then, this aphid “super‐clone” has spread to almost all sorghum‐growing areas of the country. Growers have managed the sugarcane aphid using Insecticide Resistance Action Committee (IRAC) Group 4 insecticides and the use of resistant hybrids. In order to provide additional methods of control especially for organic sorghum production, two strains of the fungal entomopathogens Beauveria bassiana and one strain of Isaria fumosorosea as well as water and Sivanto (flupyradifurone) were applied to the sugarcane aphid susceptible sorghum hybrid DKS53‐53 in a randomized complete block design (RCBD) with four replications at Tifton and Fort Valley, GA. Aphid number, plant damage, grain yield, plant dry biomass, and plant height were measured for each treatment. As compared to the treatment with water, only the plots treated with Sivanto had significantly less aphid number and plant damage and significantly more grain yield and increased plant height. Thus, the applied entomopathogens did not reduce sugarcane aphid number, did not reduce plant damage, and did not increase grain yield in either location as compared to the treatment with water (the negative control). Thus, these three strains of entomopathogens were ineffective for controlling the sugarcane aphid under these field conditions.
Bacterial community composition in agricultural soils under long‐term organic and conventional management
Authors: Fernandez Adria L. , Sheaffer Craig C. , Wyse Donald L. , Sadowsky Michael J. 
Published: June 2020

AbstractOrganic row cropping systems utilize diverse management regimes, but share required practices, including biological fertility sources, diverse rotations, incorporation of organic matter, and lack of synthetic pesticides. The practices can alter the composition of functionally significant soil microbes relative to conventional practices. We used 16S rRNA sequencing to profile soil bacterial communities at five locations where long‐term organic and conventional row cropping were practiced in close proximity on the same underlying soil type. Location effects, reflecting soil characteristics, were stronger than effects of organic vs. conventional management or corn (Zea mays L.) vs. soybean [Glycine max (L.) Merr.] cropping on the relative abundance of bacterial taxa. A core subset of 1,300 operational taxonomic units (OTUs) were detected in all sampled soils. Firmicutes made up a smaller portion of core OTUs than total OTUs, indicating that taxa in this group were more likely to be found only in specific environments. Conversely, Actinobacteria OTUs were more highly represented in the core than the full OTU set, indicating wide distribution of these taxa across environments. The genus Streptomyces comprised a five‐fold–greater proportion of core OTUs than of total OTUs. We identified 303 OTUs whose abundance differed with management system. Of those, members of the phyla Bacteroidetes and Planctomycetes tended to be more abundant under organic management, whereas members of the Actinobacteria and Verrucomicrobia tended to be more abundant in conventional. This multi‐site study contributes to identification of bacterial community members most affected by organic practice adoption across soil types and practices.
Solvation pressure in spherical mesopores: Macroscopic theory and molecular simulations
Authors: Emelianova Alina , Maximov Max A. , Gor Gennady Y. 
Published: June 2020

AbstractFluids adsorbing in nanoporous solids cause high solvation pressures that deform the solids and affect properties of the fluids themselves. We calculate solvation pressure of nitrogen adsorbed at 77.4 K in spherical silica mesopores using two methods: the macroscopic Derjaguin–Broekhoff–de Boer theory and molecular simulations. We show that both approaches give consistent results, and the observed pressures increase in smaller pores reaching the order of a hundred megapascals. The results are also typical for the solvation pressure in mesoporous materials, yet noticeably differ from the results for the cylindrical pore geometry. Furthermore, we show that the dependence of the solvation pressure at saturation on the reciprocal pore size is linear, and we use this relation for the calculation of the solid–liquid surface energy. The results can be employed for the prediction of the solvation pressure and the adsorption‐induced deformation in the material with the spherical pore geometry.
Intermediate thermal manipulation of polymers of intrinsic microporous (PIMs) membranes for gas separations
Authors: He Shanshan , Jiang Xu , Li Songwei , Ran Feitian , Long Jun , Shao Lu 
Published: June 2020

AbstractThe high fractional free volume (FFV) endowed polymers of intrinsic microporosity (PIMs) with high gas permeability but low selectivity. Herein, an intermediate temperature range was deliberately utilized to tune PIM‐1 membrane microstructure in nitrogen atmosphere to enhance gas separation performance. During intermediate thermal manipulation, the synergistic effects of thermal‐induced cross‐linking and decomposition on PIM‐1 membranes have optimized the micropores for significantly increasing membrane molecular‐sieving ability with the boosted selectivity of 350 (H2/N2), 1,472 (H2/CH4), 3,774 (H2/C3H8), and 197 (CO2/CH4) respectively, with the H2 permeability of 234 Barrer, correspondingly, surpassing the “Robeson's Upper Bound”. The facile strategy simultaneously utilizing the thermal‐induced cross‐linking and decomposition, might provide a new platform to develop the high‐performance membranes for highly‐efficient hydrogen purification and CO2 separations.
Pollination effectiveness of specialist and opportunistic nectar feeders influenced by invasive alien ants in the Seychelles
Authors: Fuster Francisco , Kaiser‐Bunbury Christopher N. , Traveset Anna 
Published: June 2020

PremiseOpportunistic nectar‐feeders may act as effective pollinators; nonetheless, we still lack information on whether these opportunistic species differ in their pollination effectiveness from specialized nectarivorous vertebrates and insects. Many nectar specialists have coevolved with the plants on which they feed; therefore, we would expect higher pollination effectiveness in specialists than in opportunistic feeders. Here, we assessed quantity and quality components of pollination effectiveness in specialist and opportunistic vertebrate nectarivores and insects, focusing on three plants from the Seychelles: Thespesia populnea, Polyscias crassa, and Syzygium wrightii.MethodsWe determined the quantity component (QNC) of pollination effectiveness with pollinator observations, and the quality component (QLC) by measuring fruit and seed set resulting from single visits by each pollinator. To detect potential negative effects of invasive ants on native plant‐pollinator interactions, we classified pollinator visits (quantity component) as disturbed (>6 ants/30 min) vs. undisturbed.ResultsAll focal plants were visited by insects, and vertebrate specialist and opportunist nectarivores, yet their pollination effectiveness differed. Flying insects were the most effective pollinators of T. populnea. The other two plants were most effectively pollinated by vertebrates; i.e., sunbirds (nectar specialists) in S. wrightii and Phelsuma geckos (nectar opportunists) in P. crassa, despite marked variation in QNC and QLC. Ant presence was associated with lower pollinator visitation rate in P. crassa and S. wrightii.ConclusionsOur study highlights the importance of all pollinator guilds, including opportunist nectarivorous vertebrates as pollinators of island plants, and the vulnerability of such interactions to disruption by nonnative species.
Youth Participatory Action Research for Health Equity: Increasing Youth Empowerment and Decreasing Physical Activity Access Inequities in Under‐resourced Programs and Schools
Authors: Abraczinskas Michelle , Zarrett Nicole 
Published: June 2020

AbstractTo address gaps in the youth participation and adolescent physical activity (PA) promotion literature, we examined the feasibility of youth participatory action research (YPAR) in (a) general aftercare (YPAR only) and (b) with a physical activity intervention, (YPAR + PA) to reach marginalized youth and impact individual empowerment and second‐order change for equitable PA access. We intervened during middle school, a developmental stage conducive to changing health habits. We used a concurrent, mixed‐method triangulation design. Participants were students (94% non‐Hispanic Black/African American, 75% free/reduced lunch) in the southeastern United States. YPAR was adapted from online modules. Youth conducted photovoice, capturing and analyzing social/environmental factors contributing to inequities in their schools/programs. PA inequities emerged for girls. Findings indicated feasibility of YPAR with systems supports. Changes occurred at the individual and systems level in the YPAR + PA program. Sociopolitical skills, participatory behavior, and perceived control empowerment subdomains increased pre–post, and youth qualitative responses aligned. A follow‐up interview with the director revealed all youth‐proposed changes occurred. A feedback loop was developed for continued youth input. Youth‐led changes to increase PA access have potential to decrease health disparities by generating unique solutions likely missed when adults intervene alone.
A randomized controlled trial of amyloid positron emission tomography results disclosure in mild cognitive impairment
Authors: Lingler Jennifer H. , Sereika Susan M. , Butters Meryl A. , Cohen Ann D. , Klunk William E. , Knox Melissa L. , McDade Eric , Nadkarni Neelesh K. , Roberts J. Scott , Tamres Lisa K. , Lopez Oscar L. 
Published: June 2020

AbstractIntroductionRecent studies suggest that Alzheimer's disease (AD) biomarker disclosure has no discernable psychological impact on cognitively healthy persons. Far less is known about how such results affect symptomatic individuals and their caregivers.MethodsRandomized controlled trial of 82 mild cognitive impairment (MCI) patient and caregiver dyads (total n = 164) to determine the effect of receiving amyloid positron emission tomography results on understanding of, and perceived efficacy to cope with, MCI over 52 weeks of follow‐up.ResultsGains in the primary outcomes were not consistently observed. Amyloid negative patients reported greater perceived ambiguity regarding MCI at follow‐up, while moderate and sustained emotional distress was observed in patients, and to a lesser extent, caregivers, of those who were amyloid positive. There was no corresponding increase in depressive symptoms.DiscussionThese findings point to the possibility that both MCI patients and caregivers may need emotional support after the disclosure of amyloid scan results.
Alleviating Cellular Oxidative Stress through Treatment with Superoxide‐Triggered Persulfide Prodrugs
Authors: Wang Yin , Dillon Kearsley M. , Li Zhao , Winckler Ethan W. , Matson John B. 
Published: June 2020

AbstractOverproduction of superoxide anion (O2.−), the primary cellular reactive oxygen species (ROS), is implicated in various human diseases. To reduce cellular oxidative stress caused by overproduction of superoxide, we developed a compound that reacts with O2.− to release a persulfide (RSSH), a type of reactive sulfur species related to the gasotransmitter hydrogen sulfide (H2S). Termed SOPD‐NAC, this persulfide donor reacts specifically with O2.−, decomposing to generate N‐acetyl cysteine (NAC) persulfide. To enhance persulfide delivery to cells, we conjugated the SOPD motif to a short, self‐assembling peptide (Bz‐CFFE‐NH2) to make a superoxide‐responsive, persulfide‐donating peptide (SOPD‐Pep). Both SOPD‐NAC and SOPD‐Pep delivered persulfides/H2S to H9C2 cardiomyocytes and lowered ROS levels as confirmed by quantitative in vitro fluorescence imaging studies. Additional in vitro studies on RAW 264.7 macrophages showed that SOPD‐Pep mitigated toxicity induced by phorbol 12‐myristate 13‐acetate (PMA) more effectively than SOPD‐NAC and several control compounds, including common H2S donors.
NIR‐II Chemiluminescence Molecular Sensor for In Vivo High‐Contrast Inflammation Imaging
Authors: Yang Yanling , Wang Shangfeng , Lu Lingfei , Zhang Qisong , Yu Peng , Fan Yong , Zhang Fan 
Published: June 2020

AbstractChemiluminescence (CL) sensing without external excitation by light and autofluorescence interference has been applied to high‐contrast in vitro immunoassays and in vivo inflammation and tumor microenvironment detection. However, conventional CL sensing usually operates in the range of 400–850 nm, which limits the performance of in vivo imaging due to serious light scattering effects and signal attenuation in tissue. To address this challenge, a new type of CL sensor is presented that functions in the second near‐infrared window (NIR‐II CLS) with a deep penetration depth (≈8 mm). Successive CL resonance energy transfer (CRET) and Förster resonance energy transfer (FRET) from the activated CL substrate to two rationally designed donor‐acceptor‐donor fluorophores BTD540 and BBTD700 occurs. NIR‐II CLS can be selectively activated by hydrogen peroxide over other reactive oxygen species (ROSs). Moreover, NIR‐II CLS is capable of detecting local inflammation in mice with a 4.5‐fold higher signal‐to‐noise ratio (SNR) than that under the NIR‐II fluorescence modality.
A Glycosylated Covalent Organic Framework Equipped with BODIPY and CaCO3 for Synergistic Tumor Therapy
Authors: Guan Qun , Zhou Le‐Le , Lv Fan‐Hong , Li Wen‐Yan , Li Yan‐An , Dong Yu‐Bin 
Published: June 2020

AbstractCa2+, a ubiquitous but nuanced modulator of cellular physiology, is meticulously controlled intracellularly. However, intracellular Ca2+ regulation, such as mitochondrial Ca2+ buffering capacity, can be disrupted by 1O2. Thus, the intracellular Ca2+ overload, which is recognized as one of the important cell pro‐death factors, can be logically achieved by the synergism of 1O2 with exogenous Ca2+ delivery. Reported herein is a nanoscale covalent organic framework (NCOF)‐based nanoagent, namely CaCO3@COF‐BODIPY‐2I@GAG (4), which is embedded with CaCO3 nanoparticle (NP) and surface‐decorated with BODIPY‐2I as photosensitizer (PS) and glycosaminoglycan (GAG) targeting agent for CD44 receptors on digestive tract tumor cells. Under illumination, the light‐triggered 1O2 not only kills the tumor cells directly, but also leads to their mitochondrial dysfunction and Ca2+ overload. An enhanced antitumor efficiency is achieved via photodynamic therapy (PDT) and Ca2+ overload synergistic therapy.
Near‐Enantiopure Trimerization of 9‐Ethynylphenanthrene on a Chiral Metal Surface
Authors: Stolz Samuel , Yakutovich Aliaksandr V. , Prinz Jan , Dienel Thomas , Pignedoli Carlo A. , Brune Harald , Gröning Oliver , Widmer Roland 
Published: June 2020

AbstractEnantioselectivity in heterogeneous catalysis strongly depends on the chirality transfer between catalyst surface and all reactants, intermediates, and the product along the reaction pathway. Herein we report the first enantioselective on‐surface synthesis of molecular structures from an initial racemic mixture and without the need of enantiopure modifier molecules. The reaction consists of a trimerization via an unidentified bonding motif of prochiral 9‐ethynylphenanthrene (9‐EP) upon annealing to 500 K on the chiral Pd3‐terminated PdGa{111} surfaces into essentially enantiopure, homochiral 9‐EP propellers. The observed behavior strongly contrasts the reaction of 9‐EP on the chiral Pd1‐terminated PdGa{111} surfaces, where 9‐EP monomers that are in nearly enantiopure configuration, dimerize without enantiomeric excess. Our findings demonstrate strong chiral recognition and a significant ensemble effect in the PdGa system, hence highlighting the huge potential of chiral intermetallic compounds for enantioselective synthesis and underlining the importance to control the catalytically active sites at the atomic level.
Mechanism of crosslinking in benzoyl peroxide‐initiated functionalization of vinyltriethoxysilane onto polypropylene in the water medium
Authors: Yuan Hao , Shao Qing , Liang Fengchun , Shi Hongwei , Song Wenbo 
Published: June 2020

AbstractSilane grafting and moisture crosslinking is one of the most common methods in the production of crosslinked polyolefin. A remarkable increase in the percentage of gel in the product was observed in benzoyl peroxide‐mediated aqueous suspension grafting of vinyltriethoxysilane onto polypropylene. Aimed to explore the crosslinking reaction mechanism in this functionalization process, comprehensive experiments had been conducted and the grafted products were characterized by mass spectrometry, 1H NMR, and 29Si NMR spectroscopy. Finally, a novel crosslinking mechanism was proposed based on the characterization results.
Dual‐phase polyphenylene oxide membranes with copolyimide branched modifiers
Authors: Tian Nadezhda S. , Meleshko Tamara K. , Polotskaya Galina A. , Kashina Anna V. , Gofman Iosif V. , Zoolshoev Zoolsho F. , Lavrentyev Victor K. , Pientka Zbynek , Yakimansky Alexander V. 
Published: June 2020

AbstractPoly(2,6‐dimethyl‐1,4‐phenylene oxide) (PPO) membranes are attractive due to high permeability for gases; however, the selectivity of these membranes is insufficient. In this work, the gas selectivity was improved without significant loss of the permeability. For this purpose, PPO was modified via incorporation of the branched copolyimide filler–grafted copolyimide (PI‐g‐PMMA) with polymethyl methacrylate (PMMA) side chains. Two series of mixed self‐supporting PPO/PI‐g‐PMMA films (with variation of the filler content) were prepared and studied as gas separation membranes. The length of the polymide (PI) chain and the density of PMMA grafting were the same in both series, however, in one series the grafted chains contained 50 MMA units, and in the other 150 units. The intermolecular interactions between the PPO matrix and the PI‐g‐PMMA fillers were investigated using viscometry, infrared (IR) spectroscopy, and scanning electron microscopy. The compatibility of the polymer components is limited; however, for both series, the contents of the respective filler are found, which ensures phase segregation only in a microscale. Therefore, the mechanical properties of the films allow their use as gas separation membranes. It is shown that the degree of the segregation as well as the mechanical and gas transport properties of the membranes depend on the length of the PMMA chains, and the membranes with filler‐containing shorter branches (50 MMA units) show better selectivity.
Molecular docking, synthesis, and characterization of chitosan‐graft‐2‐mercaptobenzoic acid derivative as potential drug carrier
Authors: Marwaha Tejinder Kaur , Madgulkar Ashwini , Bhalekar Mangesh , Asgaonkar Kalyani 
Published: June 2020

AbstractChitosan is a hydrophilic polymer with prominent mucoadhesive properties. However, it forms weak hydrogen bonds with mucin thus limiting its mucoadhesion and exhibit reduced bioavailability due to its short retention time in the body. The aim of the present study was to synthesize and characterize novel thiolated chitosan with improved functional property. A unique approach of using molecular docking to select ligand to chemically modify chitosan has been employed in the present research. A set of ligands were screened virtually using docking analysis and 2‐mercapto benzoic acid showed the lowest glide score of −4.31 Kcal/Mol thus displayed better binding interaction with chitosan. Based on the docking results, the best‐fit ligand was selected for wet lab synthesis. 2‐Mercapto benzoic acid was covalently attached to chitosan via formation of an amide bond and the reaction was mediated by carbodiimide and N‐hydroxysuccinimide. The synthesized polymer was in turn evaluated for zeta potential, Fourier transformed infrared, differential scanning calorimetry, molecular weight that confirmed conjugation of chitosan with the thiol ligand. The prepared thiomer was further subjected to mucoadhesion studies and displayed better mucoadhesion properties as compared to unmodified chitosan. Thus, the potential of the novel thiomer can be further explored as an excipient for drug delivery system with an emphasis on mucoadhesion.
C−As Bond Formation Reactions for the Preparation of Organoarsenic(III) Compounds
Authors: Tay Wee Shan , Pullarkat Sumod A. 
Published: June 2020

AbstractPotential widespread applications of organoarsenic chemistry have been limited by the inherent lack of safe and effective As−C bond formation reactions. Several alternative reagents and methods have been developed in the last few decades to address the hazards and drawbacks associated with traditional arsenic synthetic strategies. Herein, this minireview summarizes the advances made in nucleophilic, electrophilic, radical and metal‐mediated As(III)−C bond formations while specifically highlighting the behavior of arsenic synthons with various well‐established reagents (eg. Grignard reagents, organolithium compounds, organometallic reagents, radical initiators and Lewis/Brønsted bases). Avenues for asymmetric synthesis are also discussed, as are recent advances in organoarsenic chemistry suggesting that arsines exhibit novel reactivities independent from that of other relatively more well explored Group V cogeners.