bluuebunny/crossref_metadata_2025_split huggingface dataset:
Simplified Synthesis of Spherical Silica Microparticles from Rice Husk
Authors: Jang Il-Seop , Park Ji Yeon , Park Hayoung , Gu Yang Mo , Lee Jin Hyung , Chun Jinyoung 
Published: November 2021

AbstractA facile synthetic method for preparing spherical silica microparticles from rice husks was developed. Spherical silica particles with an overall size of several micrometers were obtained via direct extraction of silicate solution from rice husks, followed by precipitation of silica using nitric acid and a polymer additive. The synthetic process was simplified by omitting the acid leaching and pyrolysis processes of the rice husks. Herein, it was demonstrated that the extraction of silicate under mild conditions, combined with the use of a polyethylene glycol additive during the precipitation step, are crucial for obtaining spherical silica microparticles. Moreover, the porosity of the silica particles could be controlled by adjusting the calcination temperature.
Helic[6]arene‐Based Chiral Pseudo[1]rotaxanes and [1]Rotaxanes
Authors: Du Xu‐Sheng , Han Ying , Chen Chuan‐Feng 
Published: November 2021

AbstractChiral pseudo[1]rotaxanes and [1]rotaxanes constructed from macrocyclic arenes still remain a big challenge mainly owing to the lack of such chiral macrocycles. In this work, a new system of chiral pseudo[1]rotaxanes formed by self‐inclusion of helic[6]arene containing amide linked with the terminal tertiary amines was first discovered. Based on an atom‐economic stopping strategy, a pair of chiral [1]rotaxanes were conveniently obtained in almost quantitative yields by blocking the pseudo[1]rotaxanes with monobenzyl bromide of tetraphenylethene. The structures of pseudo[1]rotaxanes and [1]rotaxanes were characterized by 2D NMR spectra in solution, combined with DFT calculations. The photophysical properties further revealed the efficient chirality transfer of helic[6]arene to the tetraphenylethene moiety, compared to their unthreaded chiral isomers. The discovery of the chiral pseudo[1]rotaxanes allows for a wide and available synthesis of chiral [1]rotaxanes, and also opening a new avenue to the design of chiral supramolecular materials.
Efficient Extraction of Metal Ions Using a Recirculating Two‐Stage Flow Reactor
Authors: Harvie Andrew J. , de Mello John C. 
Published: November 2021

AbstractInvited for this month's cover is the group of John C. de Mello at the Norwegian University of Science and Technology in Trondheim (Norway). The cover picture shows a simple flow‐based reactor for extracting copper ions from an impure feed solution. The extraction occurs in two stages. In the first stage, the feed solution (blue) is mixed with an immiscible organic solution (orange) that contains copper‐selective extractant molecules. The copper ions rapidly transfer to the organic phase, which is then ‘tapped‐off’ using a liquid‐liquid separator. In the second stage, the organic solution is mixed with an acid solution (green), which strips the copper ions from the organic solvent. The two phases are separated using a second liquid/liquid separator. The copper solution passes straight through, while the organic solution is tapped‐off and recycled through the reactor to carry out further extractions. Read the full text of their Full Paper at 10.1002/cmtd.202100054.
The frequency of assessment of progression in randomized oncology clinical trials
Authors: Haslam Alyson , Gill Jennifer , Prasad Vinay 
Published: November 2021

AbstractBackgroundProgression in tumor assessments is often detected at a follow‐up appointment rather than when actual change in progression has occurred, which can bias PFS outcomes.AimWe sought to evaluate the frequency of tumor assessment scans in clinical trials of anti‐cancer interventions and to compare this to recommended (National Comprehensive Cancer Network) and real‐world frequencies of tumor assessments.MethodsIn a cross‐sectional analysis, we searched for articles published in the three top oncology journals between July 2017 and June 2020. We included articles that were RCTs of patients that had unresectable or metastatic solid tumors and used an intervention that was designed to be anti‐tumor. We abstracted median PFS survival for each group, the PFS hazard ratio, frequency of tumor assessment scans, tumor type, intervention type, and information regarding the study.ResultsWe found that, in the 182 comparisons (163 articles), less frequent tumor assessment (occurring more than 9 weeks between assessments) was associated with higher median PFS values for both the intervention group (p < .0001) and the control group (p < .0001). PFS hazard ratios for studies scanning for tumors every 10 or more weeks were no different than for studies scanning for tumors more frequently (p = .88). Data on the frequency of tumor assessments in the real world is sparse.ConclusionWe found that less frequent tumor assessment frequency was associated with longer median PFS in both intervention and control groups of clinical oncology trials but was not associated with differences in PFS hazard ratios. Future research is needed to compare real world to trial assessment.
Recent Advances in All‐Inorganic Zero‐Dimensional Metal Halides
Authors: Guo Yang , Chen Bing , Ren Xiaolin , Wang Feng 
Published: November 2021

AbstractAll‐inorganic zero‐dimensional (0D) metal halides are composed of isolated metal halide polyhedrons bridged by monovalent alkali metal ions. The unique structure gives rise to molecule‐like electronic configuration and consequently highly attractive optical properties. In comparison with their three‐dimensional (3D) counterparts, the 0D metal halides exhibit characteristic features such as broadband emission and long‐term stability. In addition, 0D metal halides can be constructed from a diverse range of metal ions and permit high‐level impurity doping, thereby offering great structural designability and spectral tunability. This Review surveys recent advances in 0D metal halides, including crystal preparation, luminescence modulation, and emerging applications.
Two Faces of the Bi−O Bond: Photochemically and Thermally Induced Dehydrocoupling for Si−O Bond Formation
Authors: Ramler Jacqueline , Schwarzmann Johannes , Stoy Andreas , Lichtenberg Crispin 
Published: November 2021

AbstractThe diorgano(bismuth)alcoholate [Bi((C6H4CH2)2S)OPh] (1‐OPh) has been synthesized and fully characterized. Stoichiometric reactions, UV/Vis spectroscopy, and (TD‐)DFT calculations suggest its susceptibility to homolytic and heterolytic Bi−O bond cleavage under given reaction conditions. Using the dehydrocoupling of silanes with either TEMPO or phenol as model reactions, the catalytic competency of 1‐OPh has been investigated (TEMPO=(tetramethyl‐piperidin‐1‐yl)‐oxyl). Different reaction pathways can deliberately be addressed by applying photochemical or thermal reaction conditions and by choosing radical or closed‐shell substrates (TEMPO vs. phenol). Applied analytical techniques include NMR, UV/Vis, and EPR spectroscopy, mass spectrometry, single‐crystal X‐ray diffraction analysis, and (TD)‐DFT calculations.
Synthesis of 2‐(Chlorodifluoromethyl)indoles for Nucleophilic Halogen Exchange with [18F]Fluoride
Authors: Bock Leonard , Schultheiß Stefanie K. , Maschauer Simone , Lasch Roman , Gradl Susanne , Prante Olaf , Zard Samir Z. , Heinrich Markus R. 
Published: November 2021

AbstractThe synthesis of 2‐[18F]trifluoromethylated indoles from the corresponding chlorodifluoromethyl precursors was found to proceed under milder conditions when compared to known metal‐free nucleophilic exchange reactions with [18F]fluoride on chlorodifluoro‐methyl arenes. A key element in the reaction course is – most likely – a favorable elimination‐addition mechanism on the 2‐methyl position of the indole. Given the increasing interest in 18F‐labelled compounds, this single step labeling methodology nicely complements the so far existing routes to 2‐[18F]trifluoromethylated indoles.
(R)‐BINOL‐6,6’‐bistriflone: Shortened Synthesis, Characterization, and Enantioselective Catalytic Applications
Authors: Mouhtady Omar , Castellan Tessa , André‐Barrès Christiane , Gornitzka Heinz , Fabing Isabelle , Saffon‐Merceron Nathalie , Génisson Yves , Gaspard Hafida 
Published: November 2021

AbstractThe title compound, characterized by X‐ray crystallography, was accessed in 4 steps with 92 % ee. and 25 % yield from an O‐protected (R)‐BINOL precursor. This revised synthetic route relied on a chlorosulfonylation reaction, as a shortcut to a previously developed sequence requiring the use of toxic SO2 gas and bromine. The strongly electron‐impoverished (R)‐6,6′‐Tf2‐BINOL proved an effective ligand in metal‐catalyzed enantioselective transformations such as a Zr‐based Mannich‐type reaction. The catalytic species was characterized by X‐ray crystallography as a unique tetrameric metal cluster. The 6,6′‐bistriflone groups also allowed to exalt the H‐bond donor capacity of the BINOL moiety, as illustrated in an organocatalyzed Morita‐Baylis‐Hillman transformation. Theoretical study indicated that the 6,6′‐bistriflone groups induce a drop of the phenol acidity of 5 pKa units in DMSO. Overall, this work simplified the access, completed the characterization, and confirmed the potential of (R)‐6,6′‐Tf2‐BINOL as a promising platform to further elaborate activated chiral metal ligands or organocatalysts.
Metal Nanoclusters as Versatile Building Blocks for Hierarchical Structures
Authors: Banach Ewa , Bürgi Thomas 
Published: November 2021

AbstractAtomically precise monolayer‐protected metal clusters (nanoclusters) are currently in the focus of interest due to their strongly size‐dependent properties, which gives rise to different applications, and the possibility to study the evolution of structure as a function of size. The use of truly monodisperse metal clusters as building blocks for the preparation of hierarchical structures offers exciting possibilities for the design of new materials. In this overview article we describe the current state of the art in the field of assembly of nanoclusters in one, two and three dimensions. The nanoclusters show rich chemistry that can be used for their assembly. Several reports indicate that, within the assemblies of clusters, their photoluminescence is enhanced. Although there is already a considerable body of reports on the assembly of nanoclusters, we believe that much more exciting properties of nanocluster assemblies will be discovered in the future.
Using the present to estimate the future: A simplified approach for the quantification of climate change effects on urban flooding by scenario analysis
Authors: Padulano Roberta , Costabile Pierfranco , Costanzo Carmelina , Rianna Guido , Del Giudice Giuseppe , Mercogliano Paola 
Published: November 2021

AbstractUnderstanding and modelling pluvial flood patterns is pivotal for the estimation of flood impacts in urban areas, especially in a climate change perspective. However, urban flood modelling under climate change conditions poses several challenges. On one hand, the identification and collection of climate change data suitable for flood‐related evaluations requires consistent computational and scientific effort. On the other hand, large difficulties can arise in the reproduction of the rainfall‐runoff transformation process in cases when only little information about the subsurface processes is known. In this perspective, a simplified approach is proposed to address the challenges regarding the quantitative estimation of climate change effects on urban flooding for real case applications. The approach is defined as “bottom‐up” because climate change information is not included in flood modelling, but it is only invoked for the interpretation of results. In other words, the challenge faced in this work is the development of a modelling strategy that is expeditious, because it does not require flood simulations for future rainfall scenarios, but only under current climate conditions, thus reducing the overall computational effort; and it is flexible, because results can be easily updated once new climate change data, scenarios or methods become available, without the need of additional flood simulations. To simulate real case applications, the approach is tested for a scenario analysis, where different return periods and hyetograph shapes are used as input for urban inundation modelling in Naples, Italy. The approach can support public and private stakeholders, such as land administrators and water systems managers; moreover, it represents a valuable and effective basis for climate change risk communication strategies.
Addition of spherical‐style packing improves the production of conidia by Metarhizium robertsii in packed column bioreactors
Authors: Méndez‐González Fernando , Figueroa‐Montero Arturo , Saucedo‐Castañeda Gerardo , Loera Octavio , Favela‐Torres Ernesto 
Published: November 2021

AbstractBACKGROUNDConidia from Metarhizium are part of the commercial formulations used worldwide for insect pest control. Among the alternatives proposed to improve conidia production, the use of packed column bioreactors allows controlled processes with higher levels of production and productivity than those obtained with the traditional process in plastic bags. However, problems associated with overheating, low CO2 removal, and inadequate oxygen supply in packed columns limit the scale‐up and operation at an industrial scale.RESULTSPacked densities, up to 1.5 times higher than those obtained in lab‐scale column bioreactors, negatively affected growth and conidia production by Metarhizium robertsii (ENCB‐MG‐81). Therefore, a spherical‐style packing was added to decrease packed density and improve the culture conditions in packed column bioreactors. The addition of spherical‐style packing reduced the axial temperature gradient (up to 50%), increased the maximum CO2 production rate and the total CO2 production (up to 2.5 times), and enhanced the volumetric conidia productivity in packed column bioreactors from 5.28 ± 1.36 to 6.77 ± 0.89 × 108 conidia cm−3.CONCLUSIONThe use of spherical‐style packing within the culture bed in column bioreactors improves the production of conidia by Metarhizium robertsii, as well as the gas exchange and heat removal from the bed. © 2021 Society of Chemical Industry (SCI).
Pretreatment with high oxygen controlled atmosphere enhanced fresh‐cut white mushroom (Agaricus bisporus) quality via activating wounding stress defenses
Authors: Wang Liang , Han Minjie , Cui Yingjun , Wang Xiangyou , Shan Xinhe , Wang Chongqing 
Published: November 2021

AbstractBACKGROUNDHigh oxygen treatment has been proven to be effective in fresh‐cut white mushroom preservation, however, the preservation effect and possible mechanisms in high oxygen controlled atmosphere pretreatment (HOCAP) on wounding stress are incompletely understood.RESULTSIn this study, based on the time chosen of HOCAP research, whole white mushrooms treated with 3 h HOCAP (80% O2 + 20% CO2) and the wounding resistant responses of their slices were mainly investigated through phenylpropane pathway, reactive oxygen species (ROS) scavenging system, and ascorbate–glutathione (AsA–GSH) cycle. Results showed that 3 h HOCAP can induce the production of hydrogen peroxide (H2O2) and superoxide anion (O2−•) in the early stage, as well as the NADPH oxidase activity. Enzymes and endogenous antioxidants involved in ROS scavenging were enhanced by HOCAP during the whole storage. Besides, HOCAP maintained high level of phenylalanine ammonia‐lyase (PAL) activity, enhanced the content of total phenolic and lignin, accelerated the AsA–GSH cycle.CONCLUSIONThe results demonstrated that HOCAP induced defense responses by increasing the ROS in the early stage which stimulated the activities of ROS scavenging enzymes, along with the capability of increasing for wounding stress defense and resistance. This study provides a theoretical pretreatment technology for fresh‐cut white mushroom preservation. © 2021 Society of Chemical Industry.
Polymer Nanoparticle‐Mediated Delivery of Oxidized Tumor Lysate‐Based Cancer Vaccines
Authors: Berti Cristiana , Graciotti Michele , Boarino Alice , Yakkala Chakradhar , Kandalaft Lana E. , Klok Harm‐Anton 
Published: November 2021

AbstractCancer vaccination is a powerful strategy to combat cancer. A very attractive approach to prime the immune system against cancer cells involves the use of tumor lysate as antigen source. The immunogenicity of tumor lysate can be further enhanced by treatment with hypochlorous acid. This study explores poly(lactic‐co‐glycolic acid) (PLGA) nanoparticles to enhance the delivery of oxidized tumor lysate to dendritic cells. Using human donor‐derived dendritic cells, it is found that the use of PLGA nanoparticles enhances antigen uptake and dendritic cell maturation, as compared to the use of the free tumor lysate. The ability of the activated dendritic cells to stimulate autologous peripheral blood mononuclear cells (PBMCs) is assessed in vitro by coculturing PBMCs with A375 melanoma cells. Live cell imaging analysis of this experiment highlights the potential of nanoparticle‐mediated dendritic‐cell‐based vaccination approaches. Finally, the efficacy of the PLGA nanoparticle formulation is evaluated in vivo in a therapeutic vaccination study using B16F10 tumor‐bearing C57BL/6J mice. Animals that are challenged with the polymer nanoparticle‐based oxidized tumor lysate formulation survive for up to 50 days, in contrast to a maximum of 41 days for the group that receives the corresponding free oxidized tumor lysate‐based vaccine.
Lightweight and Mechanically Robust EPDM Foams for High Thermal Insulation and Moderate Ablative Resistance Via Constructing Cellular Char Layer
Authors: Qu Hongjian , Hui Kun , Bian Cheng , Guan Yiwen , Li Hongyan , Luan Tao , Yan Ning 
Published: November 2021

AbstractEthylene propylene diene monomer (EPDM) foams have received considerable attention owing to their low weight, low thermal conductivity, and mechanical flexibility. However, their poor ablative resistance and low thermal stability make their use in severe conditions, such as the combustion chamber of a solid rocket motor, difficult. In this study, EPDM foams reinforced with aramid fibers (AFs) and carbon fibers (CFs) are prepared through a hot‐pressing‐induced foaming process. The effects of the fibers on the cellular structure, thermal stability, and mechanical, ablating, and insulating properties of the EPDM foams are investigated. The results show that the addition of CFs enhanced the thermal stability and mechanical properties of the EPDM foams, whereas the use of AFs lowered the thermal conductivity and ablation rate. In particular, when 2.5 phr (parts per hundred parts of rubber) AF and 2.5 phr CF are added, the linear ablation rate tested using oxyacetylene is 0.33 mm s−1, and the back‐face temperature is 53 °C, revealing a good balance in terms of ablative resistance and thermal insulation. Thus, the hybrid‐fiber‐reinforced EPDM foams possess several advantages, such as low weight, good thermal insulation, ablative resistance, and mechanical robustness, suggesting considerable potential for application in the aerospace industry.
Collisional experiences with Dr. Pietro Traldi and the incredible group in Padova
Authors: March Raymond Evans 
Published: November 2021

AbstractTwo Early Classic period (ca. 250–600 CE) Maya carved, greenstone jade pendants, Specimens A and B, were recovered from the Pacbitun site in Belize in 1987. The specimens were visually similar and may have been cut from a common jade piece. Mass spectrometry was considered as a technique that could possibly be used to explore the similarity of the specimens. However, at that time, neither electrospray ionization nor matrix‐assisted laser desorption/ionization (MALDI) had been discovered; furthermore, only elemental analysis had been carried out with jade samples and there were no accounts of polyatomic ions being produced from jade. The discoverer of the greenstone jade pendants, a faculty member in Anthropology at Trent University, sought the assistance of the author of this piece but no immediate progress was accomplished. About 7 years after discovery of the greenstone jade pendants, this author was invited to spend a short sabbatical leave in the laboratory of Dr. Pietro Traldi in Padova, Italy. While this invitation was attractive for several reasons, the principal attraction was Dr. Traldi's new, and mysterious acquisition of MALDI instrumentation. There was, perhaps, a single iota of reason that appeared to suggest unusual assistance of a matrix in liberating polyatomic ions from jade using laser irradiation. This account is of a very interesting sojourn with Dr. Traldi and members of his laboratory which did not lead to any immediate understanding of MALDI; however, the belief was constant for the next 20 years after which some progress was made in the exploration of the structure of jade.
Imbalanced Folate and Vitamin B12 in the Third Trimester of Pregnancy and its Association with Birthweight and Child Growth up to 2 Years
Authors: Obeid Rima , Eussen Simone J.P.M. , Mommers Monique , Smits Luc , Thijs Carel 
Published: November 2021

ScopeFolic acid supplementation during pregnancy may lead to an imbalance when vitamin B12 intake is low (folate trap) and may affect child's growth.MethodsThe authors study the association between third trimester maternal intakes of folate and B12 and birthweight and postnatal growth of 2632 infants from the KOALA Birth Cohort Study. Plasma vitamin biomarkers are measured in 1219 women.ResultsImbalanced total intakes (folate > 430 µg day−1 combined with B12 < 5.5 µg day−1) are not associated with birthweight [β adj (95% CI) = –14.87 (–68.87, 39.13)] compared with high intakes of both. Imbalanced intake is associated with a lower z score of weight at 1–2 years [β adj = –0.14 (–0.25, –0.03)]. Having red blood cell folate > 745 nmol L−1 and plasma B12 < 172 pmol L−1 is not associated with birthweight [β adj = –7.10 (–97.90, 83.71) g]. Maternal dietary B12 intake [β adj = –9.5 (–15.6, –3.3)] and plasma methylmalonic acid [β adj = 234 (43, 426)] are associated with birthweight.ConclusionLow maternal dietary B12 intake and elevated methylmalonic acid rather than imbalanced vitamins are associated with higher birthweight, suggesting that low maternal B12 can predispose the infants for later obesity.
A compact low‐cost dual‐band bandpass filter with enhanced suppression using substrate integrates suspended line technology
Authors: Zhang Yudan , Ma Kaixue , Chen Xiong 
Published: November 2021

AbstractA compact dual‐band bandpass filter based on the substrate integrates suspended line platform is proposed in this letter. The design is implemented using low‐cost FR‐4 material, while the loss can be reduced by 3D metal connections with substrate cutout. 0.97 dB/1.6 dB improvement of insertion loss is achieved and verified at 3.45 GHz/4.9 GHz. By paralleling quarter wavelength step impedance resonators with different operating frequencies, two paths formed between source and load. Both bandwidth and location of transmission zeros can be adjusted independently. Two stubs are added working not only as feed structure but also as a stop band resonator, which can provide 20 dB out‐of‐band suppression up to 4.4f0. The obtained performances are good enough to compare with the state of art, though very low‐cost FR‐4 materials are used.