bluuebunny/crossref_metadata_2025_split huggingface dataset:
In/Cu Catalyzed Multiple C−N/C−C Bond Formation via Multiple Bond Cleavage in a Three Component Synthesis of Arylimidazopyridine Carboxylates
Authors: Roslan Irwan Iskandar , Ng Kian‐Hong , Alhooshani Khalid R. , Jaenicke Stephan , Chuah Gaik‐Khuan 
Published: November 2020

AbstractA protocol for InIII and CuI co‐catalyzed synthesis of a wide array of arylimidazopyridine carboxylates by three components coupling of benzaldehydes, malonic esters and 2‐aminopyridines is described. The reaction proceeds through a reaction cascade of Knoevenagel condensation, 1,4‐conjugate addition, aerobic dehydrogenation, Ortoleva‐King reaction and decarboxylation. Multiple C−N and C−C bond formations in addition to multiple C−C, C−H, C−O, and N−H bond cleavages are involved in forming the product.
Combining Incompatible Processes for Deracemization of a Praziquantel Derivative under Flow Conditions
Authors: Valenti Giulio , Tinnemans Paul , Baglai Iaroslav , Noorduin Willem L. , Kaptein Bernard , Leeman Michel , ter Horst Joop H. , Kellogg Richard M. 
Published: November 2020

AbstractAn efficient deracemization method for conversion of the racemate to the desirable (R)‐enantiomer of Praziquantel has been developed by coupling incompatible racemization and crystallization processes. By a library approach, a derivative that crystallizes as a conglomerate has been identified. Racemization occurs via reversible hydrogenation over a palladium on carbon (Pd/C) packed column at 130 °C, whereas deracemization is achieved by alternating crystal growth/dissolution steps with temperature cycling between 5–15 °C. These incompatible processes are combined by means of a flow system resulting in complete deracemization of the solid phase to the desired (R)‐enantiomer (98 % ee). Such an unprecedented deracemization by a decoupled crystallization/racemization approach can readily be turned into a practical process and opens new opportunities for the development of essential enantiomerically pure building blocks that require harsh methods for racemization.
Translation of Mycobacterium Survival Strategy to Develop a Lipo‐peptide based Fusion Inhibitor**
Authors: Sardar Avijit , Lahiri Aritraa , Kamble Mithila , Mallick Amirul I. , Tarafdar Pradip K. 
Published: November 2020

AbstractThe entry of enveloped virus requires the fusion of viral and host cell membranes. An effective fusion inhibitor aiming at impeding such membrane fusion may emerge as a broad‐spectrum antiviral agent against a wide range of viral infections. Mycobacterium survives inside the phagosome by inhibiting phagosome–lysosome fusion with the help of a coat protein coronin 1. Structural analysis of coronin 1 and other WD40‐repeat protein suggest that the trp‐asp (WD) sequence is placed at distorted β‐meander motif (more exposed) in coronin 1. The unique structural feature of coronin 1 was explored to identify a simple lipo‐peptide sequence (myr‐WD), which effectively inhibits membrane fusion by modulating the interfacial order, water penetration, and surface potential. The mycobacterium inspired lipo‐dipeptide was successfully tested to combat type 1 influenza virus (H1N1) and murine coronavirus infections as a potential broad‐spectrum antiviral agent.
Mixed Noble‐Gas Compounds of Krypton(II) and Xenon(VI); [F5Xe(FKrF)AsF6] and [F5Xe(FKrF)2AsF6]
Authors: Lozinšek Matic , Mercier Hélène P. A. , Schrobilgen Gary J. 
Published: November 2020

AbstractThe coordination chemistry of KrF2 has been limited in contrast with that of XeF2, which exhibits a far richer coordination chemistry with main‐group and transition‐metal cations. In the present work, reactions of [XeF5][AsF6] with KrF2 in anhydrous HF solvent afforded [F5Xe(FKrF)AsF6] and [F5Xe(FKrF)2AsF6], the first mixed krypton/xenon compounds. X‐ray crystal structures and Raman spectra show the KrF2 ligands and [AsF6]− anions are F‐coordinated to the xenon atoms of the [XeF5]+ cations. Quantum‐chemical calculations are consistent with essentially noncovalent ligand−xenon bonds that may be described in terms of σ‐hole bonding. These complexes significantly extend the XeF2–KrF2 analogy and the limited chemistry of krypton by introducing a new class of coordination compound in which KrF2 functions as a ligand that coordinates to xenon(VI). The HF solvates, [F5Xe(FH)AsF6] and [F5Xe(FH)SbF6], are also characterized in this study and they provide rare examples of HF coordinated to xenon(VI).
Fast Enantio‐ and Chemoselective Arylation of Ketones with Organoboronic Esters Enabled by Nickel/N‐Heterocyclic Carbene Catalysis
Authors: Cai Yuan , Ruan Lin‐Xin , Rahman Abdul , Shi Shi‐Liang 
Published: November 2020

AbstractA general, efficient, highly enantio‐ and chemoselective N‐heterocyclic carbene (NHC)/Ni‐catalyzed addition of readily available and stable arylboronic esters to ketones is reported. This protocol provides unexpectedly fast access (usually 10 min) to various chiral tertiary alcohols with exceptionally broad substrate scope and excellent functional group tolerance (76 examples, up to 98 % ee). This process is orthogonal to other known Ni‐mediated Suzuki–Miyaura couplings, as it tolerates aryl chlorides, fluorides, ethers, esters, amides, nitriles, and alkyl chlorides. The reaction is applied to late‐stage modifications of various densely functionalized medicinally relevant molecules. Preliminary mechanistic studies suggest that a rare enantioselective η2‐coordinating activation of ketone carbonyls is involved. This cross‐coupling‐like mechanism is expected to enable other challenging transformations of ketones.
The Impact of Bilingualism on the Executive Functions of Autistic Children: A Study of English–Arabic Children
Authors: Sharaan Shereen , Fletcher‐Watson Sue , MacPherson Sarah E. 
Published: November 2020

There is evidence to suggest that certain executive functions are impaired in autistic children, contributing to many daily challenges. Regular use of two languages has the potential to positively influence executive functions, though evidence is mixed. Little is known about the impact of bilingualism on the executive functions of autistic children, with only a handful of studies published worldwide to date. This study investigated the impact of bilingualism on sustained attention, interference control, flexible switching and working memory, in Arabic–English autistic children (n = 27) and their typically developing peers (n = 66), aged 5–12 years old. Groups were matched on age, nonverbal IQ and socioeconomic status, and completed a battery of computerized tests. Results showed an advantage for bilingual autistic children relative to their monolingual peers in sustained attention, and equivalent performance between bilingual and monolingual autistic children on all other executive functions. There were no generalized positive effects of bilingualism, and typically‐developing children performed better than autistic children on all measures. The findings indicate that bilingualism does not negatively impact the executive function skills of autistic children, and that it might mitigate difficulties in sustained attention.Lay SummaryContrary to widespread belief, but in line with previous research, this study showed that speaking two languages did not harm thinking skills in autistic children. The thinking skills evaluated in this study included the ability to focus over a period of time, the ability to resist distractions, the ability to move back and forth between tasks, and the ability to use short‐term memory. In fact, speaking two languages might help reduce difficulties that autistic children might face when focusing over a period of time.
Improving viral filtration capacity in biomanufacturing processes using aggregate binding properties of polyamide‐6,6
Authors: Stanevich Vitali , Pachalla Abhishek , Nunez Briana , McInnes Mark , Nieder Christopher , Schreffler John 
Published: November 2020

AbstractVirus retention filtration is a common step in modern biopharmaceutical manufacturing as it enables efficient removal of potential adventitious and endogenous viruses via size exclusion. Modern parvovirus retention filters have significantly improved fluxes and parvovirus retention in comparison to earlier versions of these filters. However, these filters may be more susceptible to premature fouling and require more effort for process optimization. Here, we demonstrate that polyamide‐6,6 (nylon‐6,6) membranes when used as prefilters can increase the capacity of these Parvovirus retentive filters that are less susceptible to premature fouling. We found that the mechanism of polyamide‐mediated filtration improvement can be explained by the binding of monoclonal antibody (mAb) aggregates with a diameter of 20–100 nm, and we show that this mechanism is shared by other types of adsorptive prefilters. Finally, by the combination of mobile phase screening, additive spiking, and molecular dynamics simulations, we show that polyamide‐6,6 removes mAb aggregates through hydrophobic interactions making its design space potentially complementary to other available prefilters. Our studies support the aggregate‐mediated mechanism of flux decay during viral filtration and suggest that polyamide‐6,6 could be considered as an alternative cost‐effective option to extend the capacity of viral filters.
Lassa hemorrhagic shock syndrome‐on‐a‐chip
Authors: Tang Huaqi , Abouleila Yasmine , Mashaghi Alireza 
Published: November 2020

AbstractLack of experimental human models hinders research on Lassa hemorrhagic fever and the development of treatment strategies. Here, we report the first chip‐based model for Lassa hemorrhagic syndrome. The chip features a microvessel interfacing collagen network as a simple mimic for extracellular matrix, allowing for quantitative and real‐time vascular integrity assessment. Luminal infusion of Lassa virus‐like particles led to a dramatic increase in vascular permeability in a viral load‐dependent manner. Using this platform, we showed that Fibrin‐derived peptide FX06 can be used to suppress the vascular integrity loss. This simple chip‐based model proved promising in the assessment of disease severity and provides an easy‐to‐use platform for future investigation of Lassa pathogenesis and drug development in a human‐like setting.
Halophilic archaea and their potential to generate renewable fuels and chemicals
Authors: Kasirajan Lakshmi , Maupin‐Furlow Julie A. 
Published: November 2020

AbstractLignocellulosic biofuels and chemicals have great potential to reduce our dependence on fossil fuels and mitigate air pollution by cutting down on greenhouse gas emissions. Chemical, thermal, and enzymatic processes are used to release the sugars from the lignocellulosic biomass for conversion to biofuels. These processes often operate at extreme pH conditions, high salt concentrations, and/or high temperature. These harsh treatments add to the cost of the biofuels, as most known biocatalysts do not operate under these conditions. To increase the economic feasibility of biofuel production, microorganisms that thrive in extreme conditions are considered as ideal resources to generate biofuels and value‐added products. Halophilic archaea (haloarchaea) are isolated from hypersaline ecosystems with high salt concentrations approaching saturation (1.5–5 M salt concentration) including environments with extremes in pH and/or temperature. The unique traits of haloarchaea and their enzymes that enable them to sustain catalytic activity in these environments make them attractive resources for use in bioconversion processes that must occur across a wide range of industrial conditions. Biocatalysts (enzymes) derived from haloarchaea occupy a unique niche in organic solvent, salt‐based, and detergent industries. This review focuses on the use of haloarchaea and their enzymes to develop and improve biofuel production. The review also highlights how haloarchaea produce value‐added products, such as antibiotics, carotenoids, and bioplastic precursors, and can do so using feedstocks considered “too salty” for most microbial processes including wastes from the olive‐mill, shell fish, and biodiesel industries.
Impact of visual typicality on the adoption of wearables
Authors: Lee Eun‐Jung 
Published: November 2020

AbstractWith the recent influx of IT firms and big‐name fashion brands into the wearables market, the visual design of wearables has become a crucial factor in consumer choices. However, little research exists on this topic. Drawing upon the literature of technology adoption and design aesthetics, this study examines how the visual typicality of wearables affects their adoption by consumers. More specifically, the research tests the impact of the consumer‐perceived visual typicality of smartwatches on purchase intention through the psychological antecedents to wearable adoption (i.e., effort expectancy, performance expectancy, social influence, playfulness). The hypothesized relationships among the variables were tested in an online survey with 409 U.S. participants, where fictitious smartwatch designs were employed as the stimuli. In the results, perceived visual typicality of the smartwatch designs significantly decreased perceived performance and playfulness of the watch. Perceived visual typicality also had a negative impact on participants' purchase intention. Among the four psychological antecedents to wearable adoption, perceived playfulness played the most significant role in the relationship between the visual typicality and purchase intention. The moderation effect of gender was partially supported: Visual typicality significantly decreased purchase intention for females whereas it had no impact on the wearable adoption for males.
Expanding the Toolbox of R‐Selective Amine Transaminases by Identification and Characterization of New Members
Authors: Telzerow Aline , Paris Juraj , Håkansson Maria , González‐Sabín Javier , Ríos‐Lombardía Nicolas , Gröger Harald , Morís Francisco , Schürmann Martin , Schwab Helmut , Steiner Kerstin 
Published: November 2020

AbstractAmine transaminases (ATAs) are used to synthesize enantiomerically pure amines, which are building blocks for pharmaceuticals and agrochemicals. R‐selective ATAs belong to the fold type IV PLP‐dependent enzymes, and different sequence‐, structure‐ and substrate scope‐based features have been identified in the past decade. However, our knowledge is still restricted due to the limited number of characterized (R)‐ATAs, with additional bias towards fungal origin. We aimed to expand the toolbox of (R)‐ATAs and contribute to the understanding of this enzyme subfamily. We identified and characterized four new (R)‐ATAs. The ATA from Exophiala sideris contains a motif characteristic for d‐ATAs, which was previously believed to be a disqualifying factor for (R)‐ATA activity. The crystal structure of the ATA from Shinella is the first from a Gram‐negative bacterium. The ATAs from Pseudonocardia acaciae and Tetrasphaera japonica are the first characterized (R)‐ATAs with a shortened/missing N‐terminal helix. The active‐site charges vary significantly between the new and known ATAs, correlating with their diverging substrate scope.
Tetrahedral DNA Nanoconjugates for Simultaneous Measurement of Telomerase Activity and miRNA
Authors: Jiang Chenyu , Meng Fanyu , Mao Dongsheng , Tang Yuguo , Miao Peng 
Published: November 2020

AbstractIn this study, a tetrahedral DNA nanostructure was first self‐assembled; this was then conjugated with gold nanoparticles (AuNPs) and carbon nanodots (CDs). The fabricated nanocomposites allow simultaneous analysis of telomerase activity and miRNA with dual fluorescence channels. By further introducing an iRGD peptide sequence, the nanoconjuates can be conveniently transferred inside living cells for in situ imaging. The analytical performances and anti‐jamming capabilities are excellent. Meanwhile, the materials are highly biocompatible for intracellular applications. Therefore, the proposed biosystem shows great promise as a powerful tool for quantitative analysis of the dual biomarkers. The strategy can also be further exploited as a versatile platform for in situ detection of many other targets for early disease diagnosis.
Impact of early hospital discharge on clinical outcomes after transcatheter aortic valve implantation
Authors: Bække Pernille S. , Jørgensen Troels H. , Søndergaard Lars 
Published: November 2020

AbstractAimsEarly discharge after transcatheter aortic valve implantation (TAVI) may potentially impact post‐procedural safety of the patient. The study aim was to compare safety of TAVI in patients planned for fast track hospital stay with patients planned for standard hospital stay.Methods and resultsAll‐comers patients undergoing transfemoral TAVI between 2011 and 2017 were allocated to two matched groups depending whether the procedure was performed before or after transition from standard to fast track course. Data on vital status and hospitalizations were obtained through national registries.Three hundred and nineteen matched pairs were eligible for analysis. The median length of post‐procedural stay was 3 days (IQR: 2–4) for patients in the fast track group compared to 6 days (IQR: 4–8) in the standard approach group (p < .0001). There was no difference in all‐cause mortality between groups at 30‐day (1.3% vs. 1.9%, p = .52) or 90‐day follow‐up (2.9% vs. 4.1%, p = .42). There was no difference in the risk of new permanent pacemaker implantation (PPI) in pacemaker naïve patients between groups at 30‐day (15.8% vs. 21.2%, p = .16) or 90‐day follow‐up (15.8% vs. 21.9%, p = .12). There was no difference in the rate of rehospitalization between groups between discharge and 90‐day follow‐up (2.09 per patient‐year vs. 2.09 per patient‐year, p = .99).ConclusionsEarly discharge in an all‐comers population undergoing transfemoral TAVI is safe with regards to all‐cause mortality, need for PPI, and rehospitalization.
Experimental Investigation on Single‐Droplet Deformation and Breakup in a Concave‐Wall Jet
Authors: Zhang Jing , Gao Yibo , Gong Bin , Li Yaxia , Wu Jianhua 
Published: November 2020

AbstractLiquid droplets are released in the concave‐wall jet to investigate their deformation and breakup characteristics. CCl4 and water are the dispersed and continuous phases. The study reveals that the three modes of single droplets in the concave‐wall jet are non‐breakup, binary breakup, and multiple breakup. When the Weber (We) number is less than 30, the mode of binary‐breakup is primary for the droplets, however, there are only multiple‐breakup modes when We > 47. The non‐breakup and binary‐breakup modes are beneficial to the gravity and centrifugal separation because of little deformation and high axial velocity of the droplet. Effects of continuous‐phase tangential velocity and shear rate distribution on the droplet image sequence are studied. Droplet breakup occurs mainly in the region of high shear rate.
Investigation of Control Structures for a Four‐Product Laboratory Multiple Dividing‐Wall Column Using Dynamic Simulation
Authors: Preißinger Ulrich , Lukač Goran , Dejanović Igor , Grützner Thomas 
Published: November 2020

AbstractThe dynamic behavior of a multiple dividing‐wall column pilot plant is evaluated by means of dynamic simulation. Three different control structures are developed or adapted from the literature, which are constrained by the actual design features of the pilot plant column. Since in the present case the design of the column was chosen such that very different mixtures can be separated, it cannot be optimally designed for each of these potential mixtures. Rather, the design focused on the flexibility of the plant. All three investigated control structures were tested on feed flow rate and feed composition disturbance and allowed a robust control of the pilot plant, whereby control structure 2 is slightly better than others in terms of steady‐state deviations and less pronounced fluctuations during the dynamic phase. The transferability of control structure 2 to other variants of multiple dividing‐wall columns is easily possible.
The Application of Electrochemical Noise for the Study of Metal Corrosion and Organic Anticorrosion Coatings: A Review
Authors: Lv Jing , Yue Qing‐xian , Ding Rui , Wang Xiao , Gui Tai‐jiang , Zhao Xiao‐dong 
Published: November 2020

AbstractThe electrochemical noise technology and its application in the field of corrosion research are described in this paper. First, the concept, measurement method and data analysis of electrochemical noise are introduced. Then, we discuss the judgment of uniform corrosion, local corrosion and passivation through electrochemical noise. At the same time, electrochemical noise can also distinguish different local corrosion forms, such as pitting corrosion and crevice corrosion. Secondly, the mechanism and chemical kinetics of using electrochemical noise to study the pitting process are discussed. For anticorrosion coatings, electrochemical noise can give the corrosion situation and peeling degree under the coating, and then evaluate the anticorrosion performance of the coating. Finally, while discussing the application prospects of the technology, we also point out the ideal assumptions and data reliability problems currently faced by electrochemical noise technology.
Zinc Oxide Defect Microstructure and Surface Chemistry Derived from Oxidation of Metallic Zinc: Thin‐Film Transistor and Sensor Behavior of ZnO Films and Rods
Authors: Hoffmann Rudolf C. , Sanctis Shawn , Liedke Maciej O. , Butterling Maik , Wagner Andreas , Njel Christian , Schneider Jörg J. 
Published: November 2020

AbstractZinc oxide thin films are fabricated by controlled oxidation of sputtered zinc metal films on a hotplate in air at temperatures between 250 and 450 °C. The nanocrystalline films possess high relative densities and show preferential growth in (100) orientation. Integration in thin‐film transistors reveals moderate charge carrier mobilities as high as 0.2 cm2 V−1s−1. The semiconducting properties depend on the calcination temperature, whereby the best performance is achieved at 450 °C. The defect structure of the thin ZnO film can be tracked by Doppler‐broadening positron annihilation spectroscopy as well as positron lifetime studies. Comparably long positron lifetimes suggest interaction of zinc vacancies (VZn) with one or more oxygen vacancies (VO) in larger structural entities. Such VO‐VZn defect clusters act as shallow acceptors, and thus, reduce the overall electron conductivity of the film. The concentration of these defect clusters decreases at higher calcination temperatures as indicated by changes in the S and W parameters. Such zinc oxide films obtained by conversion of metallic zinc can also be used as seed layers for solution deposition of zinc oxide nanowires employing a mild microwave‐assisted process. The functionality of the obtained nanowire arrays is tested in a UV sensor device. The best results with respect to sensor sensitivity are achieved with thinner seed layers for device construction.
1,7,9,10‐Tetrasubstituted PMIs Accessible through Decarboxylative Bromination: Synthesis, Characterization, Photophysical Studies, and Hydrogen Evolution Catalysis
Authors: Costabel Daniel , Skabeev Artem , Nabiyan Afshin , Luo Yusen , Max Johannes B. , Rajagopal Ashwene , Kowalczyk Daniel , Dietzek Benjamin , Wächtler Maria , Görls Helmar , Ziegenbalg Dirk , Zagranyarski Yulian , Streb Carsten , Schacher Felix H. , Peneva Kalina 
Published: November 2020

AbstractIn this work, we present a new synthetic strategy for fourfold‐substituted perylene monoimides via tetrabrominated perylene monoanhydrides. X‐ray diffraction analysis unveiled the intramolecular stacking orientation between the substituents and semicircular packing behavior. We observed the remarkable influence of the substituent on the longevity and nature of the excited state upon visible light excitation. In the presence of poly(dehydroalanine)‐graft‐poly(ethylene glycol) graft copolymers as solubilizing template, the chromophores are capable of sensitizing [Mo3S13]2− clusters in aqueous solution for stable visible light driven hydrogen evolution over three days.