bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Network of Replication, Transcription, and Reverse Transcription of a Synthetic Genetic Cassette
Authors: Yang Hui , Eremeeva Elena , Abramov Mikhail , Herdewijn Piet 
Published: November 2020

AbstractSynthetic nucleic acids, with four non‐canonical nucleobases, can function as genetic materials. A comprehensive analysis of PCR amplification, transcription, reverse transcription, and cloning was done to screen for alternative genetic monomers. A small library of six modified nucleobases was selected: the modified 2′‐deoxyribonucleoside (dZTPs) and ribonucleoside (rZTPs) triphosphates of 7‐deaza‐adenine, 5‐chlorouracil, 7‐deaza‐guanine or inosine together with 5‐fluorocytosine or 5‐bromocytosine. The fragments composed of one to four modified nucleotides (denoted as DZA) have been successfully recognized and transcribed to natural or modified RNA (denoted as RZA) by T7 RNA polymerase. The fully modified RZA fragment could be reverse transcribed and then amplified in the presence of various dZTPs. Noticeably, modified fragments could function as genetic templates in vivo by encoding the 678 base pair gene of a fluorescent protein in bacteria. These results demonstrate the existence of a fully simulated genetic circuit that uses synthetic materials.
Inverting the Enantiopreference of Nitrilase‐Catalyzed Desymmetric Hydrolysis of Prochiral Dinitriles by Reshaping the Binding Pocket with a Mirror‐Image Strategy
Authors: Yu Shanshan , Li Jinlong , Yao Peiyuan , Feng Jinhui , Cui Yunfeng , Li Jianjiong , Liu Xiangtao , Wu Qiaqing , Lin Jianping , Zhu Dunming 
Published: November 2020

AbstractA mirror‐image strategy, that is, symmetry analysis of the substrate‐binding pocket, was applied to identify two key amino acid residues W170 and V198 that possibly modulate the enantiopreference of a nitrilase from Synechocystis sp. PCC6803 towards 3‐isobutyl glutaronitrile (1 a). Exchange of these two residues resulted in the enantiopreference inversion (S, 90 % ee to R, 47 % ee). By further reshaping the substrate‐binding pocket via routine site‐saturation and combinatorial mutagenesis, variant E8 with higher activity and stereoselectivity (99 % ee, R) was obtained. The mutant enzyme was applied in the preparation of optically pure (R)‐3‐isobutyl‐4‐cyanobutanoic acid ((R)‐2 a) and showed similar stereopreference inversion towards a series of 3‐substituted glutaronitriles. This study may offer a general strategy to switch the stereopreference of other nitrilases and other enzymes toward the desymmetric reactions of prochiral substrates with two identical reactive functional groups.
An Integrated Cofactor/Co‐Product Recycling Cascade for the Biosynthesis of Nylon Monomers from Cycloalkylamines
Authors: Sarak Sharad , Sung Sihyong , Jeon Hyunwoo , Patil Mahesh D. , Khobragade Taresh P. , Pagar Amol D. , Dawson Philip E. , Yun Hyungdon 
Published: November 2020

AbstractWe report a highly atom‐efficient integrated cofactor/co‐product recycling cascade employing cycloalkylamines as multifaceted starting materials for the synthesis of nylon building blocks. Reactions using E. coli whole cells as well as purified enzymes produced excellent conversions ranging from >80 and 95 % into desired ω‐amino acids, respectively with varying substrate concentrations. The applicability of this tandem biocatalytic cascade was demonstrated to produce the corresponding lactams by employing engineered biocatalysts. For instance, ϵ‐caprolactam, a valuable polymer building block was synthesized with 75 % conversion from 10 mM cyclohexylamine by employing whole‐cell biocatalysts. This cascade could be an alternative for bio‐based production of ω‐amino acids and corresponding lactam compounds.
Evidence of Highly Anharmonic Soft Lattice Vibrations in a Zintl Rattler
Authors: Dutta Moinak , Samanta Manisha , Ghosh Tanmoy , Voneshen David J. , Biswas Kanishka 
Published: November 2020

AbstractHere, we present lattice dynamics associated with the local chemical bonding hierarchy in Zintl compound TlInTe2, which cause intriguing phonon excitations and strongly suppress the lattice thermal conductivity to an ultralow value (0.46–0.31 W m−1 K−1) in the 300–673 K. We established an intrinsic rattling nature in TlInTe2 by studying the local structure and phonon vibrations using synchrotron X‐ray pair distribution function (PDF) (100–503 K) and inelastic neutron scattering (INS) (5–450 K), respectively. We showed that while 1D chain of covalently bonded
transport heat with Debye type phonon excitation, ionically bonded Tl rattles with a frequency ca. 30 cm−1 inside distorted Thompson cage formed by
. This highly anharmonic Tl rattling causes strong phonon scattering and consequently phonon lifetime reduces to ultralow value of ca. 0.66(6) ps, resulting in ultralow thermal conductivity in TlInTe2.
Renewable Castor‐Oil‐based Waterborne Polyurethane Networks: Simultaneously Showing High Strength, Self‐Healing, Processability and Tunable Multishape Memory
Authors: Zhang Chaoqun , Liang Haiyan , Liang Dunsheng , Lin Zirun , Chen Qian , Feng Pengju , Wang Qingwen 
Published: November 2020

AbstractMaterials with multifunctionality or multiresponsiveness, especially polymers derived from green, renewable precursors, have recently attracted significant attention resulting from their technological impact. Nowadays, vegetable‐oil‐based waterborne polyurethanes (WPUs) are widely used in various fields, while strategies for simultaneous realization of their self‐healing, reprocessing, shape memory as well as high mechanical properties are still highly anticipated. We report development of a multifunctional castor‐oil‐based waterborne polyurethane with high strength using controlled amounts of dithiodiphenylamine. The polymer networks possessed high tensile strength up to 38 MPa as well as excellent self‐healing efficiency. Moreover, the WPU film exhibited a maximum recovery of 100 % of the original mechanical properties after reprocessing four times. The broad glass‐transition temperature of the samples endowed the films with a versatile shape‐memory effect, including a dual‐to‐quadruple shape‐memory effect.
Investigations of amphiphilic butylglyceryl‐functionalized dextran nanoparticles for topical delivery
Authors: Bostanudin Mohammad F. , Muhamad Noor Noor S. , Sahudin Shariza , Mat Lazim Azwan , Tan Suk Fei , Sarker Md Zaidul I. 
Published: November 2020

AbstractToward the development of colloidal systems that can enhance transdermal permeation of hydrophilic actives, a material combining the non‐toxic of dextran with alkylglycerols permeation enhancing property has been designed. To this purpose, a range of amphiphilic butylglyceryl dextrans (DEX‐OX4) was synthesized via modification with n‐butylglycidyl ether with a degree of functionalization in the range 6.3%–35.7%. A reduced viscosity and an increased molecular weight of DEX‐OX4 were recorded when compared to the starting material. DEX‐OX4 was formulated into nanocarriers and loaded with α‐arbutin prior to characterization—the nanoparticles (180–220 nm size) were found to be close‐to‐spherical, stable at pH 5 and 7, with a loading capacity of 11.7%. Slower release of α‐arbutin from the nanoparticles was demonstrated when tested in acidic media. Lack of toxicity at application‐relevant concentrations and increased permeation were demonstrated by nanoparticles in vitro results against immortalized skin human keratinocytes cells (HaCaT).
Comparative response of Metarhizium brunneum to the cuticles of susceptible and resistant hosts
Authors: Ment Dana , Gindin Galina , Samish Michael , Glazer Itamar 
Published: November 2020

AbstractEarlier studies demonstrated that Metarhizium brunneum, usually a broad‐host pathogen of arthropods, is unable to complete its pathogenic life cycle when inoculated on the fungus‐resistant tick, Hyalomma excavatum engorged females. While the fungus penetrates the cuticle of fungus‐susceptible tick, Rhipicephalus annulatus females, it is unable to penetrate the cuticle of fungus‐resistant tick, and even perishes on its surface. This is probably due to high concentration of antifungal fatty acids and probably also due to a hypersensitive‐like response of the tick. To understand the metabolic pathways occurring in the fungal hyphae upon encountering the cuticles, we compared the response of the fungus to cuticle from susceptible and resistant tick cuticles by 2D‐gels. The intracellular proteomes of M. brunneum Mb7 exposed to cuticle of the fungus‐susceptible tick, R. annulatus, and to the fungus‐resistant tick, H. excavatum engorged females were compared after exposure to either cuticles. By means of liquid chromatography‐mass spectrometry/mass spectrometry we identified in both proteomes common proteins involved in biological processes as well as unique proteins identified only in the proteome of fungus exposed to fungus‐resistant tick cuticle. These proteins were identified in high probability as heat shock proteins, four key enzymes of the glyoxylate cycle, and proteins associated with hypoxia, and exposure to antifungal drugs. These findings are discussed within the M. brunneum‐tick pathosystem in relation to tick resistance and host resistance in general.
The first stellar parallaxes revisited
Authors: Reid Mark J. , Menten Karl M. 
Published: November 2020

AbstractWe have reanalyzed the data used by Bessel, von Struve, and Henderson in the 1830s to measure the first parallax distances to stars. We can generally reproduce their results, although we find that von Struve and Henderson have underestimated some of their measurement errors, leading to optimistic parallax uncertainties. We find that temperature corrections for Bessel's measured positions are larger than anticipated, explaining some systematics apparent in his data. It has long been a mystery as to why von Struve first announced a parallax for Vega of 0.″125 only to later revise it to double that value using more data. We resolve this mystery by finding that von Struve's early result used two dimensions of position data, which independently give significantly different parallaxes but, when combined, only fortuitously give the correct result. With later data, von Struve excluded the “problematic” dimension, leading to the larger parallax value. Allowing for likely temperature corrections and using his data from both dimensions reduce von Struve's parallax for Vega to a value consistent with the correct value.
Osteoglycin silencing exerts inhibitory effects on myocardial fibrosis and epithelial/endothelial‐mesenchymal transformation in a mouse model of myocarditis
Authors: Fang Yan , Chang Zhitang , Xu Zhicheng , Hu Jing , Zhou Haiwen , Yu Songping , Wan Xuan 
Published: November 2020

AbstractOsteoglycin (Ogn), a class III SLRP member with multiple glycosylation sites, has been proposed to be engaged in cardiac dysfunction and adverse remodeling in human heart failure following myocardial infarction. However, the underlying mechanism remains to be elucidated. Thus, we sought to define the role of Ogn in regulation of the Wnt pathway on myocardial fibrosis and epithelial/endothelial‐mesenchymal transformation (EMT/EndMT) in mice with myocarditis. The pathological changes are observed, while hematoxylin–eosin staining and picric acid Sirius red staining were conducted in successfully constructed myocarditis mouse models. Immunohistochemistry and enzyme‐linked immunosorbent assay were adopted to determine Ogn and β‐catenin levels and serum procollagen propeptide concentrations in the mouse myocardial tissues, respectively. Expression of Ogn and Wnt signaling pathway‐related factors were measured by reverse transcription quantitative polymerase chain reaction and western blot assay, cell viability by 3‐(4,5‐Dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide assay, and cell cycle distribution and apoptosis by flow cytometry. We saw indicative pathological changes accompanied by many Ogn and β‐catenin positive cells and increased serum procollagen propeptide, in the mouse myocardial tissues. Loss function assays showed reduced levels of Ogn, β‐catenin, LRP6, TGF‐β1, Twist, FSP‐1, α‐SMA and higher levels of E‐cadherin and VE‐cadherin, together with decreased proliferation rate, as well as increased apoptosis rate, indicating that the Wnt signaling pathway, proliferation were inhibited while apoptosis was enhanced with upon gene silencing. Coherently, depletion of Ogn inhibits myocardial fibroblasts proliferation and EMT/EndMT while facilitating myocardial fibroblasts apoptosis in myocarditis through the Wnt signaling pathway, thus serving as an intervention target for the molecular treatment of myocarditis.
Effect of Ni Metal Content on Emulsifying Properties of Ni/CNTox Catalysts for Catalytic Conversion of Furfural in Pickering Emulsions
Authors: Herrera C. , Pinto‐Neira J. , Fuentealba D. , Sepúlveda C. , Rosenkranz A. , García‐Fierro J. L. , González M. , Escalona N. 
Published: November 2020

AbstractNi/CNTox catalysts with variable metal content have been prepared to investigate their emulsifying and catalytic properties for the liquid‐phase conversion of furfural. The solid catalysts and emulsions were analyzed by several characterization techniques. The catalytic activity linearly increased with increasing Ni content (up to 10 wt.%) before dropping down again for a Ni content of 15 wt.%. The loss of catalytic activity was attributed to larger emulsion droplets formed by the inhibition of hydrophilic sites. All Ni/CNTox catalysts were highly selective to cyclopentanone as a main product, while several changes regarding secondary products were observed. Ni/CNTox catalysts with a Ni content up to 10 wt.% favor the formation of levulinic acid, while catalysts with a Ni content of 15 wt.% were selective to tetrahydrofurfuryl alcohol. This was attributed to an inhibition of the acid sites thus favoring the catalyst's hydrogenation capacity.
Hydrogen Bubble Templated Metal Foams as Efficient Catalysts of CO2 Electroreduction
Authors: Vesztergom Soma , Dutta Abhijit , Rahaman Motiar , Kiran Kiran , Zelocualtecatl Montiel Iván , Broekmann Peter 
Published: November 2020

AbstractThe creation of open porous structures with an extremely high surface area is of great technological relevance. The electrochemical deposition of metal foams around co‐generated hydrogen bubbles that act as templates for the deposition is a promising, cheap and simple approach to the fabrication of new electrocatalyst materials. Metal foams obtained by dynamic hydrogen bubble templating (DHBT) offer an intrinsically high electrical conductance with an open porous structure that enables the fast transport of gases and liquids. As an additional benefit, the confined space within the pores of DHBT metal foams may act as small reactors that can harbour reactions not possible at an open electrode interface. The number, distribution, and size of the pores can be fine‐tuned by an appropriate choice of the electrolysis parameters so that metal foam catalysts prepared by the DHBT technique meet certain requirements. In this paper, we review the preparation of certain metal foams, and their applications as catalysts for the electrochemical reduction of CO2.
Photochemistry in Real Space: Batho‐ and Hypsochromism in the Water Dimer
Authors: Fernández‐Alarcón Alberto , Guevara‐Vela José Manuel , Casals‐Sainz José Luis , Costales Aurora , Francisco Evelio , Martín Pendás Ángel , Rocha Rinza Tomás 
Published: November 2020

AbstractInvited for the cover of this issue is Alberto Fernández‐Alarcón and co‐workers at The Institute of Chemistry of the National Autonomous University of Mexico and The School of Chemistry of the University of Oviedo. The image depicts the real space analysis of the excitation energies in the double blue and red shift of the water dimer. Read the full text of the article at 10.1002/chem.202002854.
Analysis of Solid‐State Luminescence Emission Amplification at Substituted Anthracenes by Host–Guest Complex Formation
Authors: Schillmöller Timo , Ruth Paul Niklas , Herbst‐Irmer Regine , Stalke Dietmar 
Published: November 2020

AbstractInvited for the cover of this issue are Dietmar Stalke and coworkers from the Georg‐August Universität at Göttingen. The image symbolizes the organization of small arenes in the pocket of thiophosphoranyl substituted anthracene like the construction of a stable wall from a loose pile of bricks, shifting the emission to the green and amplifying it by a factor of five. Read the full text of the article at 10.1002/chem.202003017.
New Column Design to Enhance Flexibility: Concept for Hydrodynamic Characterization
Authors: Fasel Henrik , Grünewald Marcus , Riese Julia 
Published: November 2020

AbstractThis study presents a new and innovative sieve tray design for a more flexible operation of separation columns in terms of possible throughput. The advantage of this new tray design is to ensure an optimal operation for varying feed flow rates and constant separation efficiencies for different load ranges. The aim of this work is to give a short introduction and an outlook to the investigation of the functionality of the designed trays. Moreover, the general design of the new trays, first results for CFD simulations of the dry pressure drop and the experimental setup are presented.
Modelling the stochastic nature of porosity in a respirator canister using computational fluid dynamics
Authors: Wood Samuel G. A. , Chakraborty Nilanjan , Smith Martin W. , Summers Mark J. 
Published: November 2020

AbstractA model has been developed to represent the stochastic nature of the activated carbon bed within a generic chemical biological radiological and nuclear (CBRN) respirator canister. The porous region is subdivided into discrete sections which are assigned a porosity based on their radial position according to a longitudinally‐averaged porosity model, and then perturbed by some amount according to a Gaussian distribution. The porosity model was used in Reynolds‐averaged Navier‐Stokes (RANS) simulations in order to assess the impacts that the choice of section size and the porosity variation would have on the pressure drop and residence time distribution. It was shown for small section sizes that increasing porosity variation would increase pressure drop and minimum residence time in the carbon bed, while decreasing the average residence time. As the section sizes became larger the reverse trend was seen as a greater extent of flow channelling throughout the bed became apparent. For the given domain size, there was an upper limit to the section size, beyond which statistical convergence could not be guaranteed. It was also shown that for section sizes close to the particle diameter, the results would depend only on the ratio of section size to porosity variation, reducing the porosity model to a single parameter. A few selected cases were simulated at higher flow rates, where the previously mentioned trends were seen to persist.
DFT and Empirical Considerations on Electrocatalytic Water/Carbon Dioxide Reduction by CoTMPyP in Neutral Aqueous Solutions**
Authors: Bochlin Yair , Ben‐Eliyahu Yeshayahu , Kadosh Yanir , Kozuch Sebastian , Zilbermann Israel , Korin Eli , Bettelheim Armand 
Published: November 2020

AbstractA combined experimental and density functional theory (DFT) investigation was employed in order to examine the mechanism of electrochemical CO2 reduction and H2 formation from water reduction in neutral aqueous solutions. A water soluble cobalt porphyrin, cobalt [5,10,15,20‐(tetra‐N‐methyl‐4‐pyridyl)porphyrin], (CoTMPyP), was used as catalyst. The possible attachment of different axial ligands as well as their effect on the electrocatalytic cycles were examined. A cobalt porphyrin hydride is a key intermediate which is generated after the initial reduction of the catalyst. The hydride is involved in the formation of H2 and formate and acts as an indirect proton source for the formation of CO in these H+‐starving conditions. The experimental results are in agreement with the computations and give new insights into electrocatalytic mechanisms involving water soluble metalloporphyrins. We conclude that in addition to the porphyrin's structure and metal ion center, the electrolyte surroundings play a key role in dictating the products of CO2/H2O reduction.
Interplay between Structure and Mechanism in Reductive Dissociative Electron Transfers to α,β ‐Epoxyketones
Authors: Spencer Jared N. , Grimm Michelle L. , Tanko James M. 
Published: November 2020

AbstractThe electrochemical reduction of several α,β ‐epoxyketones was studied using cyclic (linear sweep) voltammetry, convolution voltammetry, and homogeneous redox catalysis. The results were reconciled to pertinent theories of electron transfer. α,β ‐Epoxyketones undergo dissociative electron‐transfer reactions with C−O bond cleavage, via both stepwise and concerted mechanisms, depending on their structure. For aliphatic ketones, the preferred mechanism of reduction is consistent with the “sticky” concerted model for dissociative electron transfer. Bond cleavage occurs simultaneously with electron transfer, and there is a residual, electrostatic interaction in the ring‐opened (distonic) radical anion. In contrast, for aromatic ketones, because the ring‐closed radical anions are resonance‐stabilized and exist at energy minima, a stepwise mechanism operates (electron transfer and bond cleavage occur in discrete steps). The rate constants for ring opening are on the order of 108 s−1, and not significantly affected by substituents on the 3‐membered ring (consistent with C−O bond cleavage). These results and conclusions were fully supported and augmented by molecular orbital calculations.
Liquid Biopsy Enables Quantification of the Abundance and Interindividual Variability of Hepatic Enzymes and Transporters
Authors: Achour Brahim , Al‐Majdoub Zubida M. , Grybos‐Gajniak Agnieszka , Lea Kristi , Kilford Peter , Zhang Mian , Knight David , Barber Jill , Schageman Jeoffrey , Rostami‐Hodjegan Amin 
Published: November 2020

Variability in individual capacity for hepatic elimination of therapeutic drugs is well recognized and is associated with variable expression and activity of liver enzymes and transporters. Although genotyping offers some degree of stratification, there is often large variability within the same genotype. Direct measurement of protein expression is impractical due to limited access to tissue biopsies. Hence, determination of variability in hepatic drug metabolism and disposition using liquid biopsy (blood samples) is an attractive proposition during drug development and in clinical practice. This study used a multi‐“omic” strategy to establish a liquid biopsy technology intended to assess hepatic capacity for metabolism and disposition in individual patients. Plasma exosomal analysis (n = 29) revealed expression of 533 pharmacologically relevant genes at the RNA level, with 147 genes showing evidence of expression at the protein level in matching liver tissue. Correction of exosomal RNA expression using a novel shedding factor improved correlation against liver protein expression for 97 liver‐enriched genes. Strong correlation was demonstrated for 12 key drug‐metabolizing enzymes and 4 drug transporters. The developed test allowed reliable patient stratification, and in silico trials demonstrated utility in adjusting drug dose to achieve similar drug exposure between patients with variable hepatic elimination. Accordingly, this approach can be applied in characterization of volunteers prior to enrollment in clinical trials and for patient stratification in clinical practice to achieve more precise individual dosing.