bluuebunny/crossref_metadata_2025_split huggingface dataset:
In situ encapsulated subnanometric CoO clusters within silicalite‐1 zeolite for efficient propane dehydrogenation
Authors: Song Shaojia , Li Jun , Wu Zhijie , Zhang Peng , Sun Yuanqing , Song Weiyu , Li Zhenxing , Liu Jian 
Published: September 2021

AbstractCobalt‐based catalysts are promising alternatives to replace Pt‐ and Cr‐based catalysts for propane dehydrogenation (PDH). However, the sintering and reduction of unstable Co sites cause fast deactivation. Herein, the ultrasmall cobalt oxide clusters encapsulated within silicalite‐1 zeolites (CoO@S‐1) has been obtained via a ligand assistance in situ crystallization method. This CoO@S‐1 catalyst exhibits an attractive propylene formation rate of 13.66 mmolC3H6·gcat−1·h−1 with selectivity of >92% and is durable during 120‐h PDH reaction with five successive regeneration cycles. The high PDH activity of CoO@S‐1 is assigned to the encapsulated CoO clusters are favorable for propane adsorption and can better stabilize the detached H* species from propane, leading to the lower dehydrogenation barriers than framework Co2+ cations and Co3O4 nanoparticles. Additionally, the π‐binding propylene on CoO clusters can prevent the over‐dehydrogenation reaction compared with the di‐σ binding propylene on metallic Co, leading to the superior propylene selectivity and catalytic stability.
Scalable3D‐printed lattices for pressure control in fluid applications
Authors: Woodward Ian R. , Attia Lucas , Patel Premal , Fromen Catherine A. 
Published: September 2021

AbstractAdditive manufacturing affords precise control over geometries with high degrees of complexity and predefined structure. Lattices are one class of additive‐only structures which have great potential in directing transport phenomena because they are highly ordered, scalable, and modular. However, a comprehensive description of how these structures scale and interact in heterogeneous systems is still undetermined. To advance this aim, we designed cubic and Kelvin lattices at two sub‐5‐mm length scales and compared published correlations to the experimental pressure gradient in pipes ranging from 12 to 52 mm diameter. We further investigated all combinations of the four lattices to evaluate segmented combinatorial behavior. The results suggest that a single correlation can describe pressure behavior for different lattice geometries and scales. Furthermore, combining lattice systems in series has a complex effect that is sensitive to part geometry. Together, these developments support the promise for tailored, modular lattice systems at laboratory scales and beyond.
Machine‐learning‐based construction of barrier functions and models for safe model predictive control
Authors: Chen Scarlett , Wu Zhe , Christofides Panagiotis D. 
Published: September 2021

AbstractIn this paper, we propose a control Lyapunov‐barrier function‐based model predictive control method utilizing a feed‐forward neural network specified control barrier function (CBF) and a recurrent neural network (RNN) predictive model to stabilize nonlinear processes with input constraints, and to guarantee that safety requirements are met for all times. The nonlinear system is first modeled using RNN techniques, and a CBF is characterized by constructing a feed‐forward neural network (FNN) model with unique structures and properties. The FNN model for the CBF is trained based on data samples collected from safe and unsafe operating regions, and the resulting FNN model is verified to demonstrate that the safety properties of the CBF are satisfied. Given sufficiently small bounded modeling errors for both the FNN and the RNN models, the proposed control system is able to guarantee closed‐loop stability while preventing the closed‐loop states from entering unsafe regions in state‐space under sample‐and‐hold control action implementation. We provide the theoretical analysis for bounded unsafe sets in state‐space, and demonstrate the effectiveness of the proposed control strategy using a nonlinear chemical process example with a bounded unsafe region.
Predictors of mortality and outcomes of liver transplant in spur cell hemolytic anemia
Authors: Virk Zain M. , Patel Arpan A. , Leaf Rebecca K. , Al‐Samkari Hanny 
Published: September 2021

AbstractSpur cell hemolytic anemia (SCHA) is a rare, acquired, nonimmune hemolytic anemia of decompensated cirrhosis. Data describing prognostic impact, outcomes of liver transplant, and clinical hematologic characteristics of SCHA are absent or limited. We performed a multicenter, 24‐year observational cohort study of patients with SCHA, retrospectively analyzing hepatic and hematologic parameters, independent predictors of mortality, and long‐term outcomes of liver transplant. Sixty‐nine patients with SCHA met eligibility for inclusion. The median (interquartile range) age was 53 (42–59) years; 46.4% were female, and 11 (15.9%) received liver transplant. Thirty‐nine patients (56.5%) were red blood celltransfusion‐dependent. All 11 patients undergoing transplant had rapid and complete resolution of SCHA, with improvement in median hematocrit from 22.1% to 34.6% post‐transplant (p = .001) and excellent post‐transplant outcomes. In multivariable logistic models adjusting for age, sex, etiology of cirrhosis, active/recent variceal bleeding, and Child–Turcotte–Pugh score, transfusion dependence had an odds ratio (OR) for 90‐day mortality of 9.14 (95% CI, 2.46–34.00) and reduced pre‐transfusion hematocrit had an OR of 4.73 (95% CI, 1.42–15.82) per 6% decrease; increased red cell transfusion requirement, reduced hemoglobin, increased lactate dehydrogenase, and increased indirect bilirubin were also independently predictive of higher 90‐day mortality. Model for end‐stage liver disease (MELD)‐Na and Child–Turcotte–Pugh scores consistently significantly underestimated 90‐day mortality, with standardized mortality ratios (SMRs) >1 across all scores/classes [MELD‐Na 20–29, SMR 2.42 (1.18–4.44); Child—Turcotte–Pugh class B, SMR 4.46 (1.64–9.90)]. In conclusion, SCHA is associated with substantial excess mortality than predicted by MELD‐Na or Child–Turcotte–Pugh scores and uniformly resolves with liver transplant, without recurrence. Multiple parameters of hemolytic anemia severity independently predict higher 90‐day mortality.
Triazolyl Dibenzo[a,c]phenazines Stabilize Telomeric G‐quadruplex and Inhibit Telomerase
Authors: Pal Sarmistha , Fatma Khushnood , Ravichandiran Velayutham , Dash Jyotirmayee 
Published: September 2021

AbstractWe herein report the synthesis and biophysical evaluation of triazolyl dibenzo[a,c]phenazine derivatives as a novel class of G‐quadruplex ligands. The aromatic core facilitates π‐π interaction and the flexible, protonable side chains interact with the phosphate backbone of DNA via electrostatic interactions. Förster resonance energy transfer (FRET) melting assay and isothermal titration calorimetry (ITC) studies suggest that these ligands show binding preference for the hTELO G‐quadruplex over G‐quadruplexes found in the promoter region of various oncogenes and duplex DNA. The in vitro telomeric repeat amplification protocol (Q‐TRAP) assay reveals that these ligands reduce telomerase activity in cancer cells.
A Platform for Site‐Specific DNA‐Antibody Bioconjugation by Using Benzoylacrylic‐Labelled Oligonucleotides
Authors: Konč Juraj , Brown Libby , Whiten Daniel R. , Zuo Yukun , Ravn Peter , Klenerman David , Bernardes Gonçalo J. L. 
Published: September 2021

AbstractMany bioconjugation strategies for DNA oligonucleotides and antibodies suffer limitations, such as site‐specificity, stoichiometry and hydrolytic instability of the conjugates, which makes them unsuitable for biological applications. Here, we report a new platform for the preparation of DNA‐antibody bioconjugates with a simple benzoylacrylic acid pentafluorophenyl ester reagent. Benzoylacrylic‐labelled oligonucleotides prepared with this reagent can be site‐specifically conjugated to a range of proteins and antibodies through accessible cysteine residues. The homogeneity of the prepared DNA‐antibody bioconjugates was confirmed by a new LC‐MS protocol and the bioconjugate probes were used in fluorescence or super‐resolution microscopy cell imaging experiments. This work demonstrates the versatility and robustness of our bioconjugation protocol that gives site‐specific, well‐defined and plasma‐stable DNA‐antibody bioconjugates for biological applications.
trans Single‐Stranded DNA Cleavage via CRISPR/Cas14a1 Activated by Target RNA without Destruction
Authors: Wei Yangdao , Yang Zhiqing , Zong Chengli , Wang Buhua , Ge Xiaolin , Tan Xiao , Liu Xin , Tao Zhenzhen , Wang Peng , Ma Chunxin , Wan Yi , Li Jinghong 
Published: September 2021

AbstractAs a CRISPR‐Cas system (clustered regularly interspaced short palindromic repeats and CRISPR associated proteins), Cas14a1 can cis/trans cleave single‐stranded DNA (ssDNA). Here, we describe an unreported capacity of Cas14a1: RNA can trigger the trans ssDNA cleavage. This Cas14a1‐based RNA‐activated detection platform (Amplification, Transcription, Cas14a1‐based RNA‐activated trans ssDNA cleavage, ATCas‐RNA) has an outstanding specificity for the detection of target RNAs with point mutation resolution, which is better than that of the Cas14a1‐based ssDNA‐activation. Using ATCas‐RNA via a fluorophore quencher‐labeled ssDNA reporter (FQ), we were able to detect 1 aM pathogenic nucleic acid within 1 h, and achieve 100 % accuracy with 25 milk samples. This platform can serve as a new tool for high‐efficiency nucleic acid diagnostics. Importantly, this work can expand our understanding of Cas14a1 and inspire further mechanisms and applications of Class‐2 Cas systems.
Smart Nanozyme Platform with Activity‐Correlated Ratiometric Molecular Imaging for Predicting Therapeutic Effects
Authors: Teng Lili , Han Xiaoyu , Liu Yongchao , Lu Chang , Yin Baoli , Huan Shuangyan , Yin Xia , Zhang Xiao‐Bing , Song Guosheng 
Published: September 2021

AbstractNanozymes with intrinsic enzyme‐like characteristics have attracted enormous research interest in biological application. However, there is a lack of facile approach for evaluating the catalytic activity of nanozymes in living system. Herein, we develop a novel manganese‐semiconducting polymer‐based nanozyme (MSPN) with oxidase‐like activity for reporting the catalytic activity of itself in acid‐induced cancer therapy via ratiometric near‐infrared fluorescence (NIRF)‐photoacoustic (PA) molecular imaging. Notably, MSPN possess oxidase‐like activity in tumor microenvironment, owing to the mixed‐valent MnOx nanoparticles, which can effectively kill cancer cells. Because the semiconducting polymer (PFODBT) is conjugated with oxidase‐responsive molecule (ORM), the catalytic activity of nanozyme can be correlated with the ratiometric signals of NIRF (FL695/FL825) and PA (PA680/PA780), which may provide new ideas for predicting anticancer efficacy of nanozymes in living system.
Nitrosobenzene‐Enabled Chiral Phosphoric Acid Catalyzed Enantioselective Construction of Atropisomeric N‐Arylbenzimidazoles
Authors: An Qian‐Jin , Xia Wang , Ding Wei‐Yi , Liu Huan‐Huan , Xiang Shao‐Hua , Wang Yong‐Bin , Zhong Guofu , Tan Bin 
Published: September 2021

AbstractDescribed herein is an imidazole ring formation strategy for the synthesis of axially chiral N‐arylbenzimidazoles by means of chiral phosphoric acid catalysis. Two sets of conditions were developed to transform two classes of 2‐naphthylamine derivatives into structurally diverse N‐arylbenzimidazole atropisomers with excellent chemo‐ and regioselectivity as well as high levels of enantiocontrol. It is worth reflecting on the unique roles played by the nitroso group in this domino reaction. It functions as a linchpin by first offering an electrophilic site (N) for the initial C−N bond formation while the resulting amine performs the nucleophilic addition to form the second C−N bond. Additionally, it could facilitate the final oxidative aromatization as an oxidant. The atropisomeric products could be conveniently elaborated to a series of axially chiral derivatives, enabling the exploitation of N‐arylbenzimidazoles for their potential utilities in asymmetric catalysis.
gem‐Difluoroallylation of Aryl Halides and Pseudo Halides with Difluoroallylboron Reagents in High Regioselectivity
Authors: Sakamoto Shu , Butcher Trevor W. , Yang Jonathan L. , Hartwig John F. 
Published: September 2021

AbstractWe report the palladium‐catalyzed gem‐difluoroallylation of aryl halides and pseudo halides with 3,3‐difluoroallyl boronates in high yield with high regioselectivity, and we report the preparation of the 3,3‐difluoroallyl boronate reactants by a copper‐catalyzed defluorinative borylation of inexpensive gaseous 3,3,3‐trifluoropropene with bis(pinacolato)diboron. The gem‐difluoroallylation of aryl and heteroaryl bromides proceeds with low catalyst loading (0.1 mol % [Pd]) and tolerates a wide range of functional groups, including primary alcohols, secondary amines, ethers, ketones, esters, amides, aldehydes, nitriles, halides, and nitro groups. This protocol extends to aryl iodides, chlorides, and triflates, as well as substituted difluoroallyl boronates, providing a versatile synthesis of gem‐difluoroallyl arenes that we show to be valuable intermediates to a series of fluorinated building blocks.
Deciphering and Suppressing Over‐Oxidized Nitrogen in Nickel‐Catalyzed Urea Electrolysis
Authors: Li Jianan , Li Jili , Liu Tao , Chen Lin , Li Yefei , Wang Hualin , Chen Xiurong , Gong Ming , Liu Zhi‐Pan , Yang Xuejing 
Published: September 2021

AbstractUrea electrolysis is a prospective technology for simultaneous H2 production and nitrogen suppression in the process of water being used for energy production. Its sustainability is currently founded on innocuous N2 products; however, we discovered that prevalent nickel‐based catalysts could generally over‐oxidize urea into NO2− products with ≈80 % Faradaic efficiencies, posing potential secondary hazards to the environment. Trace amounts of over‐oxidized NO3− and N2O were also detected. Using 15N isotopes and urea analogues, we derived a nitrogen‐fate network involving a NO2−‐formation pathway via OH−‐assisted C−N cleavage and two N2‐formation pathways via intra‐ and intermolecular coupling. DFT calculations confirmed that C−N cleavage is energetically more favorable. Inspired by the mechanism, a polyaniline‐coating strategy was developed to locally enrich urea for increasing N2 production by a factor of two. These findings provide complementary insights into the nitrogen fate in water–energy nexus systems.
Biosynthesis of phenylpyruvic acid from l‐phenylalanine using chromosomally engineered Escherichia coli
Authors: Xiong Tianzhen , Bai Yajun , Fan Tai‐Ping , Zheng Xiaohui , Cai Yujie 
Published: September 2021

AbstractThe efficiency of whole‐cell biotransformation is often affected by the genetic instability of plasmid‐based expression systems, which require selective pressure to maintain the stability of the plasmids. To circumvent this shortcoming, we constructed a chromosome engineering strain for the synthesis of phenylpyruvic acid (PPA) from l‐phenylalanine. First, l‐amino acid deaminase (pmLAAD) from Proteus myxofaciens was incorporated into Escherichia coli BL21 (DE3) chromosome and the copy numbers of pmLAAD were increased by chemically induced chromosomal evolution (CIChE). Fifty‐nine copies of pmLAAD were obtained in E. coli BL8. The PPA titer of E. coli BL8 reached 2.22 g/L at 6 h. Furthermore, the deletion of lacI improved PPA production. In the absence of isopropyl‐β‐d‐thiogalactopyranoside, the resulting strain, E. coli BL8△recA△lacI, produced 2.65 g/L PPA at 6 h and yielded a 19.37% increase in PPA production compared to E. coli BL8△recA. Finally, the engineered E. coli BL8△recA△lacI strain achieved 19.14 g/L PPA at 24 h in a 5‐L bioreactor.
Maternotoxicity and fetotoxicity in Rattus norvegicus albinus exposed to tramadol during the late phase of pregnancy
Authors: Akhtar Muhammad Furqan , Younas Sobia , Saleem Ammara , Baig Mirza Muhammad Faran Ashraf , Sharif Ali , Abdel‐Daim Mohamed M. , Rasul Azhar , Saleem Mohammad 
Published: September 2021

AbstractObjectivesTramadol, an atypical opioid, is clinically efficacious in treating moderate to severe pain. The aim of current study was to find out the toxicological effects of tramadol exposure to pregnant rats and fetuses during the late phase of pregnancy.MethodsWistar pregnant rats were exposed to 1.25, 2.5, or 5 mg/kg/day tramadol from 14th to 20th day of pregnancy. The same therapy was given to nonpregnant rats for 7 days. The body weight, oral glucose and lipid tolerance tests, and effect on complete blood parameters in both pregnant and nonpregnant rats were determined. On 20th day, maternal placentas were excised and weighed while fetuses were observed for any deformity and growth retardation. Oxidative stress biomarkers were estimated in the liver and kidney tissue homogenates of the pregnant and nonpregnant rats while the whole fetus homogenate was processed for the same. Moreover, histopathology of the liver and kidney of pregnant and nonpregnant rats were carried out.ResultsTramadol administration did not significantly alter the area under curve of the blood glucose and triglyceride levels in both the pregnant and nonpregnant rats. It reduced the live fetuses, placental weights, fetal length, and fetal weights. Tramadol treated pregnant rats showed significantly (p < .05) reduced red blood cells, hematocrit, hemoglobin, and platelets with reference to control group. Similarly, structural abnormalities and malfunctioning of the liver and kidney of pregnant rats were instituted; however, it did not affect the structural integrity of nonpregnant rats. A substantial (p < .001–.0001) altered glutathione and malondialdehyde levels in the fetuses, pregnant, and nonpregnant animals (tissue homogenates) at all dosage levels were indicative of tramadol induced oxidative stress. Furthermore, tramadol exposure resulted in more significant (p < .01–.001) alteration of lipid profile in the pregnant than the nonpregnant animals.ConclusionAcquired results suggested the maternotoxic and fetotoxic effects of tramadol exposure during the late gestation period.
Structural Basis of Cyclic 1,3‐Diene Forming Acyl‐Coenzyme A Dehydrogenases
Authors: Kung Johannes W. , Meier Anne‐Katrin , Willistein Max , Weidenweber Sina , Demmer Ulrike , Ermler Ulrich , Boll Matthias 
Published: September 2021

AbstractThe biologically important, FAD‐containing acyl‐coenzyme A (CoA) dehydrogenases (ACAD) usually catalyze the anti‐1,2‐elimination of a proton and a hydride of aliphatic CoA thioesters. Here, we report on the structure and function of an ACAD from anaerobic bacteria catalyzing the unprecedented 1,4‐elimination at C3 and C6 of cyclohex‐1‐ene‐1‐carboxyl‐CoA (Ch1CoA) to cyclohex‐1,5‐diene‐1‐carboxyl‐CoA (Ch1,5CoA) and at C3 and C4 of the latter to benzoyl‐CoA. Based on high‐resolution Ch1CoA dehydrogenase crystal structures, the unorthodox reactivity is explained by the presence of a catalytic aspartate base (D91) at C3, and by eliminating the catalytic glutamate base at C1. Moreover, C6 of Ch1CoA and C4 of Ch1,5CoA are positioned towards FAD‐N5 to favor the biologically relevant C3,C6‐ over the C3,C4‐dehydrogenation activity. The C1,C2‐dehydrogenation activity was regained by structure‐inspired amino acid exchanges. The results provide the structural rationale for the extended catalytic repertoire of ACADs and offer previously unknown biocatalytic options for the synthesis of cyclic 1,3‐diene building blocks.
LncRNA TUG1 acts as a competing endogenous RNA to mediate CTGF expression by sponging miR‐133b in myocardial fibrosis after myocardial infarction
Authors: Zhang Songlin , Wang Ningbo , Ma Qingyan , Fan Fenling , Ma Xiancang 
Published: September 2021

AbstractMyocardial fibrosis (MF) is one of the basic causes of many cardiovascular diseases. Noncoding RNAs (ncRNAs), including microRNA (miRNA) and long noncoding RNA (lncRNA), have been reported to play an indispensable role in MF. The current work is focused on investigating the biological role of lncRNA taurine upregulation gene 1 (TUG1) in activating cardiac myofibroblasts as well as the underlying mechanism. The outcome revealed that after myocardial infarction TUG1 expression increased and miR‐133b expression decreased in the rat model of MF. The expression level of TUG1 increased following AngII treatment in cardiac myofibroblast. TUG1 knockdown inhibited the Ang‐II induced cardiac myofibroblast activation and TUG1 overexpression increased proliferation and collagen generation of cardiac myofibroblasts. Bioinformatic prediction programs predicted that TUG1 had MRE directly combined with miR‐133b seed sequence, luciferase activity, and RIP experiments indicated that TUG1, acted as a sponger and interacted with miR‐133b in cardiac myofibroblasts. Furthermore, a target of miR‐133b was CTGF and CTGF knockdown counteracted the promotion of MF by miR‐133b knockdown. Collectively, our study suggested that TUG1 mediates CTGF expression by sponging miR‐133b in the activation of cardiac myofibroblasts. The current work reveals a unique role of the TUG1/miR‐133b/CTGF axis in MF, thus suggesting its immense therapeutic potential in the treatment of cardiac diseases.
Determination of Relative Stabilities of Metal‐Peptide Bonds in the Gas Phase
Authors: Cziferszky Monika , Truong Dianna , Hartinger Christian G. , Gust Ronald 
Published: September 2021

AbstractUnderstanding binding site preferences in biological systems as well as affinities to binding partners is a crucial aspect in metallodrug development. We here present a mass spectrometry‐based method to compare relative stabilities of metal‐peptide adducts in the gas phase. Angiotensin 1 and substance P were used as model peptides. Incubation with isostructural N‐heterocyclic carbene (NHC) complexes of RuII, OsII, RhIII, and IrIII led to the formation of various adducts, which were subsequently studied by energy‐resolved fragmentation experiments. The gas‐phase stability of the metal‐peptide bonds depended on the metal and the binding partner. Of the four complexes used, the OsII derivative bound strongest to Met, while RuII formed the most stable coordination bond with His. RhIII was identified as the weakest peptide binder and IrIII formed peptide adducts with intermediate stability. Probing these intrinsic gas‐phase properties can help in the interpretation of biological activities and the design of site‐specific protein binding metal complexes.
Domino Dehydrative π‐Extension: A Facile Path to Extended Perylenes and Terrylenes
Authors: Feofanov Mikhail , Akhmetov Vladimir , Amsharov Konstantin 
Published: September 2021

AbstractHerein, we report a new method for synthesis of extended perylenes and terrylenes. The technique is based on the cascade dehydrative π‐extensions (DPEX) of aryl aldehydes, in which stepwise annulations activate previously “dormant” substituents. Two‐ and fourfold cyclizations of 3‐aryl‐biphenyl‐2,2′‐dicarbaldehydes offer a rapid path to unsymmetrical perylenes and elusive terrylene derivatives, respectively. DPEX of 3,3′′‐(phenanthrene‐1,8‐diyl)bis (([1,1′‐biphenyl]‐2,2′‐dicarbaldehyde)) leads to the biradical structure, which proceeds in situ into oxidative electrocyclization at room temperature. The described domino process complements and expands DPEX approach to a large family of fused acenes and related PAHs.
Perfluorinated Trialkoxysilanol with Dramatically Increased Brønsted Acidity
Authors: Feige Felix , Malaspina Lorraine A. , Rychagova Elena , Ketkov Sergey , Grabowsky Simon , Hupf Emanuel , Beckmann Jens 
Published: September 2021

AbstractThe Brønsted acidity of the perfluorinated trialkoxysilanol {(F3C)3CO}3SiOH is more than 13 orders of magnitude higher than that of orthosilicic acid, Si(OH)4, and even more for most previously known silanols. It is easily deprotonated by simple amines and pyridines to give the conjugate silanolates [OSi{OC(CF3)3}3]−, which possess extremely short Si−O bonds, comparable to those of silanones.