bluuebunny/crossref_metadata_2025_split huggingface dataset:
Genome‐Mining‐Based Discovery of the Cyclic Peptide Tolypamide and TolF, a Ser/Thr Forward O‐Prenyltransferase
Authors: Purushothaman Mugilarasi , Sarkar Snigdha , Morita Maho , Gugger Muriel , Schmidt Eric W. , Morinaka Brandon I. 
Published: February 2021

AbstractCyanobactins comprise a widespread group of peptide metabolites produced by cyanobacteria that are often diversified by post‐translational prenylation. Several enzymes have been identified in cyanobactin biosynthetic pathways that carry out chemically diverse prenylation reactions, representing a resource for the discovery of post‐translational alkylating agents. Here, genome mining was used to identify orphan cyanobactin prenyltransferases, leading to the isolation of tolypamide from the freshwater cyanobacterium Tolypothrix sp. The structure of tolypamide was confirmed by spectroscopic methods, degradation, and enzymatic total synthesis. Tolypamide is forward‐prenylated on a threonine residue, representing an unprecedented post‐translational modification. Biochemical characterization of the cognate enzyme TolF revealed a prenyltransferase with strict selectivity for forward O‐prenylation of serine or threonine but with relaxed substrate selectivity for flanking peptide sequences. Since cyanobactin pathways often exhibit exceptionally broad substrate tolerance, these enzymes represent robust tools for synthetic biology.
A Multifunctional Dysprosium‐Carboxylato 2D Metall–Organic Framework
Authors: González Jonay , Sevilla Pablo , Gabarró‐Riera Guillem , Jover Jesús , Echeverría Jorge , Fuertes Sara , Arauzo Ana , Bartolomé Elena , Sañudo E. Carolina 
Published: February 2021

AbstractWe report the microwave assisted synthesis of a bidimensional (2D) MOF of formula [Dy(MeCOO)(PhCOO)2]n (1) and its magnetically diluted analogue [La0.9Dy0.1(MeCOO)(PhCOO)2] (1 d). 1 is a 2D material with single‐ion‐magnet (SIM) behaviour and 1 d is a multifunctional, magnetic and luminescent 2D material. 1 can be exfoliated into stable nanosheets by sonication.
Boosting Electroreduction Kinetics of Nitrogen to Ammonia via Tuning Electron Distribution of Single‐Atomic Iron Sites
Authors: Li Yan , Li Junwei , Huang Junheng , Chen Junxiang , Kong Yan , Yang Bin , Li Zhongjian , Lei Lecheng , Chai Guoliang , Wen Zhenhai , Dai Liming , Hou Yang 
Published: February 2021

AbstractElectrocatalytic nitrogen reduction reaction (NRR) plays a vital role for next‐generation electrochemical energy conversion technologies. However, the NRR kinetics is still limited by the sluggish hydrogenation process on noble‐metal‐free electrocatalyst. Herein, we report the rational design and synthesis of a hybrid catalyst with atomic iron sites anchored on a N,O‐doped porous carbon (FeSA‐NO‐C) matrix of an inverse opal structure, leading to a remarkably high NH3 yield rate of 31.9 μg
h−1 mg−1cat. and Faradaic efficiency of 11.8 % at −0.4 V for NRR electrocatalysis, outperformed almost all previously reported atomically dispersed metal‐nitrogen‐carbon catalysts. Theoretical calculations revealed that the observed high NRR catalytic activity for the FeSA‐NO‐C catalyst stemmed mainly from the optimized charge‐transfer between the adjacent O and Fe atoms homogenously distributed on the porous carbon support, which could not only significantly facilitate the transportation of N2 and ions but also effectively decrease the binding energy between the isolated Fe atom and *N2 intermediate and the thermodynamic Gibbs free energy of the rate‐determining step (*N2 → *NNH).
Elevated Urate Levels Do Not Alter Bone Turnover Markers: Randomized Controlled Trial of Inosine Supplementation in Postmenopausal Women
Authors: Dalbeth Nicola , Horne Anne , Mihov Borislav , Stewart Angela , Gamble Gregory D. , Merriman Tony R. , Stamp Lisa K. , Reid Ian R. 
Published: February 2021

ObjectiveObservational studies have consistently demonstrated that serum urate level positively correlates with bone mineral density (BMD). We undertook this study to determine whether moderate hyperuricemia induced by inosine supplements influences bone turnover markers in postmenopausal women over a 6‐month period.MethodsOne hundred twenty postmenopausal women were recruited for a 6‐month randomized, double‐blind, placebo‐controlled trial. Key exclusion criteria were osteoporosis, previous fragility fracture, bisphosphonate therapy, gout, kidney stones, and a urine pH level of ≤5.0. Participants were randomized in a 1:1 ratio to receive placebo or inosine. The coprimary end points were change in levels of N‐propeptide of type I procollagen (PINP) and change in levels of β‐C‐telopeptide of type I collagen (β‐CTX). Change in BMD, as measured by dual x‐ray absorptiometry, was an exploratory end point.ResultsAdministration of inosine led to a significant increase in serum urate concentration over the study period (P < 0.0001 for all follow‐up time points). At week 26, the mean change in serum urate concentration was +0.13 mmoles/liter (+2.2 mg/dl) in the inosine group and 0.00 mmoles/liter (0 mg/dl) in the placebo group. There was no difference in PINP or β‐CTX levels between groups over the 6 months. There were no significant changes in bone density between groups over the 6 months. Adverse events and serious adverse events were similar between the 2 groups.ConclusionThis clinical trial shows that although inosine supplementation leads to sustained increases in serum urate levels over a 6‐month period, it does not alter markers of bone turnover in postmenopausal women. These findings do not support the concept that urate has direct biologic effects on bone turnover.
Heavier Tetrylenes as Single Site Catalysts
Authors: Sen Nilanjana , Khan Shabana 
Published: February 2021

AbstractAn overview of the development of compounds with heavier low‐valent group 14 elements (known as tetrylenes) as single component catalyst for organic transformation has been provided. Compounds with heavier group 14 elements possess stereochemically active lone pairs and energetically accessible π‐antibonding orbitals, thereby resembling the electronic configuration of transition‐metal compounds. Such compounds with low‐valent group 14 elements has been known for small molecule activation since Power's report of dihydrogen activation by a digermyne, but their utilization in catalysis remained as a “Holy Grail” in main group chemistry. In recent years, numerous methodologies have been discovered epitomizing the use of Si(II), Ge(II) and Sn(II) compounds as single site catalysts for hydroboration of aldehydes, ketones, pyridines, cyanosilylation of aldehydes and ketones, N‐formylations aromatic amines, dehydrocoupling reactions. This mini‐review highlights these significant developments with an emphasis on the mechanistic investigation.
Fundamental parameters and non‐local thermodynamic equilibrium abundances of key light elements for nine bright and nearby K giants
Authors: Lyubimkov Leonid S. , Korotin Sergey A. , Petrov Dmitry V. , Poklad Dmitry B. , Mkrtichian David E. , Han Inwoo , Lee Byeong‐Cheol 
Published: February 2021

AbstractFor nine bright K giants within 100 pc of the sun, the fundamental parameters and the non‐local thermodynamic equilibrium (LTE) abundances of three key light elements (Li, C, and O) are accurately determined. These stars are of special interest due to the planets detected around them. Their fundamental parameters are found to be typical for K giants; in particular, these stars have effective temperatures Teff = 3,920–4,830 K, surface gravities log g = 1.20–2.85, masses M = 1.2–2.8 M⊙, and ages t = 0.4–5.4 Gyr (the pronounced anticorrelation between ages t and masses M exists). The microturbulent parameter Vt derived from Fe I lines varies between 1.2 and 1.9 km s−1; the metallicity index [Fe/H] forfive stars is close to the normal (zero) value, for other four stars it varies between −0.3 and −0.4 dex. All the giants are on the red giant branch stage and passed the first‐dredge‐up (FDU) phase. This conclusion is confirmed by the published low isotope ratios 12C/13C and 16O/17O. Basing on the non‐LTE analysis of Li I, C I, and O I lines, we determined abundances of lithium, carbon, and oxygen, three tracers of stellar evolution. The carbon deficiency −0.3 dex is found for the giants, which is quite expectable for these post‐FDU objects. The oxygen abundance is likely to be unchanged, whereas for the C/O ratio we obtained (after correction due to galactic chemical evolution) the mean value [C/O]cor = −0.22 ± 0.10 that is in very good agreement with the theory. The lithium abundance is not detected for seven of nine program giants; this result is quite expectable for the post‐FDU stars. We determined the Li abundance with the confidence only for two giants, namely, log ϵ(Li) = 0.92 for β Gem and log ϵ(Li) = 0.45 for μ Leo; this result contradicts the standard theory. Hypothetical engulfment by a star of a giant planet could solve the problem.
Tracing production instability in a clonally derived CHO cell line using single‐cell transcriptomics
Authors: Tzani Ioanna , Herrmann Nicholas , Carillo Sara , Spargo Cathy A. , Hagan Ryan , Barron Niall , Bones Jonathan , Shannon Dillmore W. , Clarke Colin 
Published: February 2021

AbstractA variety of mechanisms including transcriptional silencing, gene copy loss, and increased susceptibility to cellular stress have been associated with a sudden or gradual loss of monoclonal antibody (mAb) production in Chinese hamster ovary (CHO) cell lines. In this study, we utilized single‐cell RNA‐seq (scRNA‐seq) to study a clonally derived CHO cell line that underwent production instability leading to a dramatic reduction of the levels of mAb produced. From the scRNA‐seq data, we identified subclusters associated with variations in the mAb transgenes and observed that heavy chain gene expression was significantly lower than that of the light chain across the population. Using trajectory inference, the evolution of the cell line was reconstructed and was found to correlate with a reduction in heavy and light chain gene expression. Genes encoding for proteins involved in the response to oxidative stress and apoptosis were found to increase in expression as cells progressed along the trajectory. Future studies of CHO cell lines using this technology have the potential to dramatically enhance our understanding of the characteristics underpinning efficient manufacturing performance as well as product quality.
Extraction Yield, Chemical Composition, Preliminary Toxicity of Bignonia nocturna (Bignoniaceae) Essential Oil and in Silico Evaluation of the Interaction
Authors: Santana de Oliveira Mozaniel , Pereira da Silva Valdeline Maria , Cantão Freitas Lucas , Gomes Silva Sebastião , Nevez Cruz Jorddy , de Aguiar Andrade Eloisa Helena 
Published: February 2021

AbstractBignonia nocturna (Bignoniaceae) is a plant used for medicinal purposes by the Amazonian indigenous peoples. To date, there have been no reported studies on its toxicity. The present study aimed to evaluate the chemical composition of essential oils obtained from Bignonia nocturna by different extraction techniques. In addition, an in silico study of the molecular interactions was performed using molecular docking and molecular dynamics. The extractions were carried out by hydrodistillation, simultaneous distillation‐extraction, and steam distillation, using samples collected from the Amazon in summer and winter. The chemical composition was analyzed by GC/FID and GC/MS, and the cytotoxic activity in Artemia salina Leach was evaluated. The maximum yield (1.38 % w/w) was obtained by hydrodistillation. The results indicated that benzaldehyde predominated in all the fractions of both the volatile concentrate and the essential oils. In addition, the oil proved to be highly toxic to Artemia salina. The computer simulation results indicated that benzaldehyde strongly interacts with acetylcholinesterase, which is the likely interaction mechanism responsible for the cytotoxicity.
Effect of Drag Models on the Numerical Simulations of Bubbling and Turbulent Fluidized Beds
Authors: Varghese Mona Mary , Vakamalla Teja Reddy , Mantravadi Bhargav , Mangadoddy Narasimha 
Published: February 2021

AbstractGranular option enabled two‐fluid model coupled with different homogeneous and heterogeneous drag correlations, i.e., Gidaspow, Syamlal and O'Brien, Beetstra, Brucato, Gibilaro, energy minimization multiscale method (EMMS), and Tenneti, are employed for the prediction of bubbling and turbulent fluidized‐bed characteristics. Numerically predicted results are validated against the literature data in terms of bubble shape and diameter, axial and radial variation of time‐averaged void fraction, pressure drop, and bed expansion. The Gidaspow, Syamlal and O'Brien drag model‐predicted mean void fraction and bubble shapes are close to the experiments in bubbling and turbulent fluidized beds with both the 2D and 3D geometries. All drag models overpredicted the pressure drop at low superficial gas velocities in a turbulent fluidized bed.
Acid‐Thermally Modified Merremia vitifolia for the Removal of 2,4‐Dichlorophenoxyacetic Acid
Authors: Aswani Meethale Theruvinthalakkal , Kumar Malladi Venkata Pavan 
Published: February 2021

AbstractAn acid‐thermally modified Merremia vitifolia biosorbent (ATMVB) was used for the removal of 2,4‐dichlorophenoxyacetic acid (2,4‐D) from its aqueous solution. The characteristics of ATMVB were found to be superior to that of the unmodified Merremia vitifolia biosorbent (UMMVB). Batch biosorption experimental data under the optimal treatment conditions for ATMVB best fitted to a pseudo‐first‐order kinetics model and Langmuir adsorption isotherm with a defined maximum biosorption capacity. The mechanism of biosorption was explained with two intraparticle diffusion models, namely, Weber and Boyd. The biosorption is exothermic as per the thermodynamic studies. The ATMVB can be considered as a potential biosorbent for the removal of 2,4‐D from its aqueous solution.
A DNA‐Encoded Chemical Library Based on Peptide Macrocycles
Authors: Onda Yuichi , Bassi Gabriele , Elsayed Abdullah , Ulrich Franziska , Oehler Sebastian , Plais Louise , Scheuermann Jörg , Neri Dario 
Published: February 2021

AbstractThe synthesis and characterization of a novel DNA‐encoded library of macrocyclic peptide derivatives are described; the macrocycles are based on three sets of proteinogenic and non‐proteinogenic amino acid building blocks and featuring the use of copper(I)‐catalyzed alkyne‐azide cycloaddition (CuAAC) reaction for ring closure. The library (termed YO‐DEL) which contains 1 254 838 compounds, was encoded with DNA in single‐stranded format and was screened against target proteins of interest using affinity capture procedures and photocrosslinking. YO‐DEL selections yielded specific binders against serum albumins, carbonic anhydrases and NKp46, a marker of activated Natural Killer cells.
Isolation and Structural Determination of a Hexacoordinated Antimony(V) Dication
Authors: Sakabe Masato , Sato Soichi 
Published: February 2021

AbstractInvited for the cover of this issue are Masato Sakabe and Soichi Sato at Tokyo Metropolitan University. The image depicts the new hexacoordinated dicationic antimony species reported in this work. Read the full text of the article at 10.1002/chem.202004659.
One‐Pot Synthesis of Coumarin–Indomethacin Hybrids as COX‐2 Targeting Probes for Cancer Imaging
Authors: Wet‐osot Sirawit , Pewklang Thitima , Chansaenpak Kantapat , Chudapongse Nuannoi , Lai Rung‐Yi , Kamkaew Anyanee 
Published: February 2021

AbstractFacile synthesis of 6‐ or 7‐substituted coumarin‐indomathacin hybrids (Coum‐IDM) has been developed for specific cyclooxygenase‐2 (COX‐2) binding along with their intrinsic fluorescent properties. A mild and rapid condensation/dehydrative cyclization of 2‐hydroxy benzaldehyde with activated indomethacin was carried out in one step under ultrasound irradiation. Coum‐IDM4 was found to be the best of this series as it presented significant binding to COX‐2 and exhibited higher fluorescent intensity in cancer cells than in normal cells. Therefore, in the light of drug development tools, this new hybrid system could be a potential targeted probe for COX‐2‐overexpressed inflammation and cancer‐cell tracking.
Opening the proverbial ‘can of worms’ on trauma‐specific treatment in prison: The association of adverse childhood experiences to treatment outcomes
Authors: Messina Nena Portia , Schepps Mitchell 
Published: February 2021

AbstractA large body of research has shown that incarcerated populations have a high prevalence of adverse childhood experiences (ACEs), increasing their risk for associated mental health problems and violent and aggressive behaviours. Emerging research on treatment for trauma survivors shows evidence that incarcerated women and men, with the most complex histories of trauma and abuse, can be responsive to trauma‐specific treatment. Current research assessing two gender‐responsive and trauma‐specific brief interventions (e.g., Healing Trauma for Women and Exploring Trauma for Men) have demonstrated feasibility, consistency and efficacy among incarcerated populations. The current study uses secondary data analysis to explore the relationship between cumulative ACEs and the impact of the Healing Trauma and Exploring Trauma on participant's (682 women and 624 men) mental health, aggression and anger outcomes. The mixed‐method regression results show that the impact of ACEs on treatment outcomes is strong and cumulative (i.e., greater exposure to childhood traumatic events increased the likelihood of participant programme gain on all the mental health and aggression outcomes, ranging from .13 to 1.2 for women and .15 to .77 for the men). The lowest significant coefficient for both women and men was for verbal anger and the largest was for current trauma symptoms. The association of ACEs on anger outcomes varied between women and men (revealing more association among the men). The findings show a strong positive impact for the trauma‐specific brief interventions, particularly for those with the highest levels of trauma, whom otherwise might not have been ineligible for any programme participation.
Photodriven Charge Accumulation and Carrier Dynamics in a Water‐Soluble Carbon Nitride Photocatalyst
Authors: Li Chunyu , Hofmeister Elisabeth , Krivtsov Igor , Mitoraj Dariusz , Adler Christiane , Beranek Radim , Dietzek Benjamin 
Published: February 2021

AbstractCharge accumulation in photoactive molecules and materials holds great promise in solar energy conversion as it allows for decoupling solar‐driven charging from (dark) redox reactions. In this contribution, light‐driven charge accumulation was investigated for a recently reported novel water‐soluble carbon nitride [K,Na‐poly(heptazine imide); K,Na‐PHI] photocatalyst, which exhibits excellent activity and stability in highly selective photocatalytic oxidation of alcohols and concurrent reduction of dioxygen to H2O2 under quasi‐homogeneous conditions. An excellent charge storage ability of the K,Na‐PHI material was demonstrated, showing an optimal density of accumulated electrons (32.2 μmol of electrons per gram) in the presence of 10 vol % MeOH as a sacrificial electron donor. The long‐lived electrons accumulated under anaerobic conditions as K,Na‐PHI.− radical ions were utilized in interfacial electron transfer to O2 or methyl viologen in a subsequent dark reaction. Ultrafast time‐resolved spectroscopy was employed to reveal the kinetics of charge‐carrier recombination and methanol oxidation. Geminate recombination of electrons and holes within approximately 100 ps was followed by trap‐assisted recombination. The presence of methanol as a sacrificial electron donor accelerated the decay of the transient absorption signal when a static sample was used. This behavior was ascribed to the faster charge recombination in the presence of the radical anions generated after hole extraction. The work suggests that photodriven electron storage in the water‐soluble carbon nitride is enabled by localized trap states, and highlights the importance of the effective electron donor for creating long‐lived photo‐generated carbon nitride radicals.
Design Strategies of Non‐Noble Metal‐Based Electrocatalysts for Two‐Electron Oxygen Reduction to Hydrogen Peroxide
Authors: Zhao Hui , Yuan Zhong‐Yong 
Published: February 2021

AbstractHydrogen peroxide (H2O2) is a highly value‐added and environmentally friendly chemical with various applications. The production of H2O2 by electrocatalytic 2e− oxygen reduction reaction (ORR) has drawn considerable research attention, with a view to replacing the currently established anthraquinone process. Electrocatalysts with low cost, high activity, high selectivity, and superior stability are in high demand to realize precise control over electrochemical H2O2 synthesis by 2e− ORR and the feasible commercialization of this system. This Review introduces a comprehensive overview of non‐noble metal‐based catalysts for electrochemical oxygen reduction to afford H2O2, providing an insight into catalyst design and corresponding reaction mechanisms. It starts with an in‐depth discussion on the origins of 2e−/4e− selectivity towards ORR for catalysts. Recent advances in design strategies for non‐noble metal‐based catalysts, including carbon nanomaterials and transition metal‐based materials, for electrochemical oxygen reduction to H2O2 are then discussed, with an emphasis on the effects of electronic structure, nanostructure, and surface properties on catalytic performance. Finally, future challenges and opportunities are proposed for the further development of H2O2 electrogeneration through 2e− ORR, from the standpoints of mechanistic studies and practical application.
Detection of LongR3‐IGF‐I, Des(1‐3)‐IGF‐I, and R3‐IGF‐I using immunopurification and high resolution mass spectrometry for antidoping purposes
Authors: Mongongu Cynthia , Coudoré François , Domergue Valérie , Ericsson Magnus , Buisson Corinne , Marchand Alexandre 
Published: February 2021

AbstractInsulin‐like growth factor‐I (IGF‐I) and its analogs LongR3‐IGF‐I, Des(1‐3)‐IGF‐I, and R3‐IGF‐I are prohibited substances in sport. Although they were never approved for use in humans, they are readily available as black market products for bodybuilding and can be used to enhance physical performance. This study's aims were to validate a fast and sensitive detection method for IGF‐I analogs and to evaluate their detectability after intramuscular administration in rats. The sample preparation consisted of an immunopurification on MSIA™ microcolumns using a polyclonal anti‐human‐IGF‐I antibody. The target substances were then directly analyzed by nano‐liquid chromatography coupled with high‐resolution mass spectrometry. Abundant signs of lower quality, oxidized peptide forms were found in black market products, justifying the need to monitor at least both the native and mono‐oxidized forms. The analytical performance of this method (linearity, carry over, detection limits, precision, specificity, recovery, and matrix effect) was studied by spiking the analogs into human serum. Following a single intramuscular administration (100 μg/kg) in rats, detection was evaluated up to 36 h after injection. While unchanged Des(1‐3)‐IGF‐I and R3‐IGF‐I were detected until 24 h after administration, LongR3‐IGF‐I disappeared rapidly after 4 h. Des(1)‐LongR3‐IGF‐I, a new N‐terminal Long‐R3‐IGF‐I degradation product, was detected in addition to Des(1‐10)‐LongR3‐IGF‐I and Des(1‐11)‐LongR3−IGF‐I: the latter was detected up to 16 h. The same products were found after in vitro incubation of the analogs in human whole blood, suggesting that observations in rats may be extrapolated to humans and that the validated method may be applicable to antidoping testing.