bluuebunny/crossref_metadata_2025 huggingface dataset:
Peripheral RAFT Polymerization on a Covalent Organic Polymer with Enhanced Aqueous Compatibility for Controlled Generation of Singlet Oxygen
Authors: Lai Haiwang , Yan Jieyu , Liu Shan , Yang Qizhi , Xing Feiyue , Xiao Pu
Published: March 2020

A covalent organic polymer (COP) is prepared by crosslinking the photosensitizer 4,4′,4′′,4′′′‐(porphyrin‐5,10,15,20‐tetrayl)tetraaniline (TAPP) with 4,4′‐(anthracene‐9,10‐diyl)dibenzoic acid (ADDA) via 1‐ethyl‐3‐(3‐dimethylaminopropyl)carbodiimide/4‐dimethylaminopyridine coupling. The COP is further modified with a hydrophilic polymer, poly(poly(ethylene glycol) methyl ether methacrylate) by grafting‐from reversible‐addition‐fragmentation chain transfer (RAFT) polymerization to enhance its solubility in various solvents. The modified COP can bind singlet oxygen through the formation of endoperoxide by ADDA upon the exposure to red light irradiation. Singlet oxygen can be then released via the photodynamic mechanism or the cycloreversion by endoperoxide when heated at 110 °C. These results open new possibilities for simultaneous generation of singlet oxygen by the photodynamic route and singlet oxygen carriers, demonstrating promise for treating hypoxic tumors.
Catalytic Behavior of Mono‐N‐Protected Amino‐Acid Ligands in Ligand‐Accelerated C−H Activation by Palladium(II)
Authors: Salazar Chase A. , Gair Joseph J. , Flesch Kaylin N. , Guzei Ilia A. , Lewis Jared C. , Stahl Shannon S.
Published: March 2020

Mono‐N‐protected amino acids (MPAAs) are increasingly common ligands in Pd‐catalyzed C−H functionalization reactions. Previous studies have shown how these ligands accelerate catalytic turnover by facilitating the C−H activation step. Here, it is shown that MPAA ligands exhibit a second property commonly associated with ligand‐accelerated catalysis: the ability to support catalytic turnover at substoichiometric ligand‐to‐metal ratios. This catalytic role of the MPAA ligand is characterized in stoichiometric C−H activation and catalytic C−H functionalization reactions. Palladacycle formation with substrates bearing carboxylate and pyridine directing groups exhibit a 50–100‐fold increase in rate when only 0.05 equivalents of MPAA are present relative to PdII. These and other mechanistic data indicate that facile exchange between MPAAs and anionic ligands coordinated to PdII enables a single MPAA to support C−H activation at multiple PdII centers.
Öffnung der Valenzschale: Ein T‐förmiges Eisen(I)‐Metalloradikal und sein Potential als Atomabstraktor
Authors: Ott Jonas C. , Wadepohl Hubert , Gade Lutz H.
Published: March 2020

Ein thermisch stabiler, T‐förmiger d7‐High‐Spin‐Eisen(I)‐Komplex wurde durch die Reduktion eines PNP‐stablisierten Eisen(II)‐Chlorido‐Komplexes erhalten. Paramagnetische NMR‐Spektroskopie, gekoppelt mit einer DFT‐Modellierung, ermöglichte die Analyse der elektronischen Struktur dieser koordinativ hochgradig ungesättigten Verbindung. Der Metalloradikalcharakter der Verbindung wurde durch die Bildung eines Ketyl‐Radikalkomplexes unter Versetzen mit Benzophenon gezeigt. Außerdem weist der Komplex eine reichhaltige Chemie als Sauerstoffatom‐Abstraktor von Epoxiden unter Bildung eines zweikernigen, Oxo‐verbrückten Eisen(II)‐Komplexes auf.
Lyapunov‐based EMPC of constrained nonlinear systems with changing economic costs
Authors: He Defeng , Xu Shan
Published: March 2020

There exist frequent economic cost changes in many process systems due to variations in price, market demand, disturbance, etc. This change switches the economic setpoint of processes throughout their operation and may cause a loss of feasibility and/or stability in economic model predictive control (EMPC). In this paper, we present a novel Lyapunov‐based EMPC scheme for optimization of changing economic costs of constrained nonlinear systems. The dual‐mode paradigm is used to guarantee stability and constraint satisfaction in the presence of changing economic costs. Parameterization control actions are also adopted to decrease the computational effort of solving EMPC optimization. An equilibrium manifold is introduced to unify the terminal regions of local control Lyapunov functions (CLFs) and this enlarges the domain of attraction of the closed‐loop system with EMPC. Moreover, the proposed controller is shown to be always feasible for any change in economic costs and asymptotic stable by providing some CLFs of the nonlinear system. Finally, an example of CSTR is exploited to demonstrate the effectiveness of the proposed scheme, compared with traditional EMPC.
Recent Progress in Calix[n]quinone (n=4, 6) and Pillar[5]quinone Electrodes for Secondary Rechargeable Batteries
Authors: Zhang Meng , Zhang Yi , Huang Weiwei , Zhang Qichun
Published: March 2020

Attributing to the advantages of high theoretical specific capacity, good structural designability and environmental friendliness, organic quinone electrode materials have been applied in secondary batteries to achieve great electrochemical performances. At present, a series of researches about secondary batteries with quinone‐based compounds calix[4]quinone (C4Q), pillar[5]quinone (P5Q) and calix[6]quinone (C6Q) as cathodes have been carried out. In this review, we systematically summarize the applications of these three types of quinone compounds in lithium‐ion batteries (LIBs), sodium‐ion batteries (SIBs), zinc‐ion batteries (ZIBs), and magnesium‐ion batteries (Mg‐ion batteries). The optimizing methods for suppressing the dissolution of organic electrode materials such as quasi‐solid‐state electrolytes, all‐solid‐state electrolytes, ionic liquid electrolytes, aqueous electrolytes and carbon immobilization are concluded. This review could provide a good guideline to improve the electrochemical performances of secondary batteries using quinone compounds as cathodes in the future.
Enhanced production of Dopa‐incorporated mussel adhesive protein using engineered translational machineries
Authors: Jeong Ye Seul , Yang Byeongseon , Yang Byungseop , Shin Mincheol , Seong Jihyoun , Cha Hyung Joon , Kwon Inchan
Published: March 2020

Mussel adhesive proteins (MAPs) have great potential as bioglues, particularly in wet conditions. Although in vivo residue‐specific incorporation of 3,4‐dihydroxyphenylalanine (Dopa) in tyrosine‐auxotrophic Escherichia coli cells allows for production of Dopa‐incorporated bioengineered MAPs (dMAPs), the low production yield hinders the practical application of dMAPs. This low production yield of dMAPs is due to low translational activity of a noncanonical amino acid, Dopa, in E. coli cells. Herein, to enhance the production yield of dMAPs, we investigated the coexpression of Dopa‐recognizing tyrosyl‐tRNA synthetases (TyrRSs). To use the Dopa‐specific Methanococcus jannaschii TyrRS (MjTyrRS‐Dopa), we altered the anticodon of tyrosyl‐tRNA amber suppressor into AUA (MjtRNATyrAUA) to recognize a tyrosine codon (AUA). Co‐overexpression of MjTyrRS‐Dopa and MjtRNATyrAUA increased the production yield of Dopa‐incorporated MAP foot protein type 3 (dfp‐3) by 57%. Similarly, overexpression of E. coli TyrRS (EcTyrRS) led to a 72% higher production yield of dfp‐3. Even with coexpression of Dopa‐recognizing TyrRSs, dfp‐3 has a high Dopa incorporation yield (over 90%) compared to ones prepared without TyrRS coexpression.
Nonthermal Plasma‐Induced Degradation of Morin and Enhancement of Biological Activities
Authors: Jeong Gyeong Han , Kim Tae Hoon
Published: March 2020

In the present study, non‐thermal dielectric barrier discharge (DBD) plasma of induced structural changes of morin resulted in the isolation of one previously undescribed benzofuranone derivative, along with two known compounds. The chemical structures of these degradation products were elucidated by UV, NMR and FAB‐MS spectroscopic analyses. The isolated three compounds showed potent antioxidative activities in two different tests, with IC50 values in the range of 12.9–41.8 μm in the 2,2′‐azino‐bis (3‐ethylbenzothiazoline‐6‐sulfonic acid) (ABTS+) radical scavenging activity, 19.0–71.9 μm for hydroxyl radical scavenging activity test. Furthermore, the new methoxylated benzofuranone exhibited enhancement of inhibitory effects against pancreatic lipase with an IC50 value of 90.7±1.6 μm, when compared to the parent morin. These results suggested that the degradation products isolated from plasma exposed morin might be beneficial for prevention of obesity and related diseases.
Assembly of a DNA Origami Chinese Knot by Only 15% of the Staple Strands
Authors: He Kai , Li Zhe , Liu Longfei , Zheng Mengxi , Mao Chengde
Published: March 2020

As a giant leap in DNA self‐assembly, DNA origami has exhibited an unprecedented ability to construct nanostructures with arbitrary shapes and sizes. In typical DNA origami, hundreds of short DNA staple strands fold a long, single‐stranded (ss) DNA scaffold cooperatively into designed nanostructures. However, large numbers of DNA strands are expensive and would hinder applications such as pharmaceutical investigations because of the complicated components. Therefore, one challenge is how to reduce the number of staple strands needed to construct DNA origami. For a DNA origami structure, the scale‐free folding pattern of the scaffold strand is determined by staple strands at the branching vertexes. Simple duplex regions help to define the size‐related features of the origami geometry. In this study, we hypothesized that a scaffold strand can be correctly folded into a designed topology by using only staple strands involved in branching vertexes. After assembly, any remaining, flexible, single‐stranded regions of the scaffold could be converted into rigid duplexes by DNA polymerase to achieve the designed geometric structures. To demonstrate the concept, we used only 18 staple strands (covering 15 % of the scaffold strand) to assemble a porous DNA nanostructure, which was visualized by atomic force microscopy (AFM). This study helps understanding of the role of cooperativity in origami folding, and provides a cost‐effective approach for small‐scale prototyping DNA origami.
Resolution by Preferential Crystallization of Proxyphylline by Using Its Salicylic Acid Monohydrate Co‐Crystal
Authors: Harfouche Lina C. , Brandel Clément , Cartigny Yohann , Petit Samuel , Coquerel Gérard
Published: March 2020

The monohydrated co‐crystal composed of the chiral active pharmaceutical ingredient proxyphylline, salicylic acid, and water was successfully resolved by preferential crystallization from a water/ethanol mixture. To the best of our knowledge, this is the first report of preferential crystallization applied to such a system and the results reveal that unusually high enantiomeric excess values can be attained in the mother liquor. These robust and reproducible results underline the potential of preferential crystallization to resolve co‐crystal systems.
Polyacrylonitrile/α‐Fe2O3 Hybrid Photocatalytic Composite Adsorbents for Enhanced Dye Removal
Authors: Mohammadreza Miraboutalebi Seyed , Peydayesh Mohammad , Bagheri Maryam , Mohammadi Toraj
Published: March 2020

The potential of a novel α‐Fe2O3/polyacrylonitrile (PAN) hybrid composite adsorbent to eliminate methylene blue (MB) from aqueous solution was evaluated. PAN was selected as the base composite. The presence of α‐Fe2O3 as nanophotocatalyst on the surface of PAN introduced an efficient photocatalytic hybrid composite adsorbent for degrading MB. Effects of α‐Fe2O3 nanopowder loading, pH, temperature, MB initial concentration, solar light, and contact time were investigated. Langmuir, Freundlich, and Temkin isotherms were applied to analyze the adsorption behavior. The Freundlich equation provided the best correlation with experimental data. Pseudo‐first‐order, pseudo‐second‐order, and intraparticle models were employed. Thermodynamic studies indicated an endotherm and spontaneous adsorption process in a defined temperature range.
Creating Competitive Active Sites on CNTs Walls by N‐Doping and Sublayer Co4N Encapsulating for Efficient Hydrogen Evolution Reaction
Authors: Jiao Mingyang , Wang Zhiheng , Chen Zhipeng , Zhang Xinxin , Mou Kaiwen , Zhang Wei , Liu Licheng
Published: March 2020

An excellent catalyst can be effectively designed by adjusting its electronic structure. In this paper, an efficient hydrogen evolution reaction (HER) catalyst, carbon nanotubes with N doping and sublayer Co4N encapsulating (N−CNTs@Co4N) supported on Ni foam (NF), was designed and prepared through a complementary electronic structure principle. The as‐prepared N−CNTs@Co4N@NF catalyst shows outstanding hydrogen evolution activity in 1.0 M KOH solution. DFT calculation indicated that carbon nanotubes wall of N−CNTs@Co4N@NF catalyst provided more competitive catalytic active sites for hydrogen evolution reaction than N doped CNTs and Co4N singly. The greatly improved catalytic ability was owing to the redistribution of electron density for N−CNTs after Co4N embeds in, leading to a moderate absorption energy of H. This study demonstrated the successful rational design and experimental verification on developing a novel non‐noble metal catalyst.
A Path to More Sustainable Catalysis: The Critical Role of LiBr in Avoiding Catalyst Death and its Impact on Cross‐Coupling
Authors: Eckert Philip , Organ Michael G.
Published: March 2020

The role that LiBr plays in the lifetime of Pd‐NHC complexes has been investigated. A bromide ion is proposed to coordinate to Pd thereby preventing beta hydride elimination (BHE) (to form NHC‐H+) of the reductive elimination (RE) intermediate that normally completes with the desired cross‐coupling catalytic cycle. Coordinating groups, such as anilines, are able to bind suitably well to Pd to prevent this pathway from occurring, thus reducing the need for the added salt. The metal hydride formed from BHE is very unstable and RE of the hydride to the NHC ligand occurs very rapidly giving rise to the corresponding hydrido‐NHC (i.e., NHC‐H+). The use of the per deuterated dibutylzinc shows a significant deuterium isotope effect, shutting down catalyst death almost completely. The use of bis‐neopentylzinc, now possessing no hydrides, eliminates catalyst death all together leading to a very long‐lived catalytic cycle and confirming the untoward role of BHE.
Temperature‐Dependent Electrochemical Properties and Electrode Kinetics of Na3V2(PO4)2O2F Cathode for Sodium‐Ion Batteries with High Energy Density
Authors: Zhao Xin‐Xin , Gu Zhen‐Yi , Li Wen‐Hao , Yang Xu , Guo Jin‐Zhi , Wu Xing‐Long
Published: March 2020

Phosphate cathode materials are practical for use in sodium‐ion batteries (SIBs) owing to their high stability and long‐term cycle life. In this work, the temperature‐dependent properties of the phosphate cathode Na3V2(PO4)2O2F (NVPOF) are studied in a wide temperature range from −25 to 55 °C. Upon cycling at general temperature (above 0 °C), the NVPOF cathode retains an excellent charge/discharge performance, and the rate capability is noteworthy, indicating that NVPOF is a competitive candidate as a temperature‐adaptive cathode for SIBs. Upon decreasing the temperature below 0 °C, the cell performance deteriorates, which may be caused by the electrolyte and Na electrode, based on the study of ionic conductivity and electrode kinetics. This work proposes a new breakthrough point for the development of SIBs with high performance over a wide temperature range for advanced power systems.
Para‐Selective Cyanation of Arenes by H‐Bonded Template
Authors: Pimparkar Sandeep , Bhattacharya Trisha , Maji Arun , Saha Argha , Jayarajan Ramasamy , Dutta Uttam , Lu Gang , Lupton David W. , Maiti Debabrata
Published: March 2020

The significance of site selective functionalization stands upon the superior selectivity, easy synthesis and diverse product utility. In this work, we demonstrate the para‐selective introduction of versatile nitrile moiety, enabled by a detachable and reusable H‐bonded auxiliary. The methodology holds its efficiency irrespective of substrate electronic bias. The conspicuous shift in the step energetics was probed by both experimental and computational mechanistic tools, which heralds the inception of para‐deuteration. The synthetic impact of the methodology was highlighted with reusability of directing group and post synthetic modifications.
The enantioselective enrichment, metabolism, and toxicity of fenoxaprop‐ethyl and its metabolites in zebrafish
Authors: Xu Yangguang , Jing Xu , Zhai Wangjing , Li Xuefeng
Published: March 2020

To investigate the impacts of the widely used chiral herbicide fenoxaprop‐ethyl (FE) on aquatic organisms, the enrichment, metabolism, acute toxicity, and oxidative stress of fenoxaprop‐ethyl and its main metabolites fenoxaprop (FA), ethyl‐2‐(4‐hydroxyphenoxy)propanoate (EHPP), 2‐(4‐hydroxyphenoxy)propanoic acid (HPPA), and 6‐chloro‐2,3‐dihydrobenzoxazol‐2‐one (CDHB) in zebrafish were studied. The enantioselectivity of fenoxaprop‐ethyl and its chiral metabolites was also determined. Fenoxaprop‐ethyl quickly degraded in zebrafish by aquatic exposure. FA, HPPA, and CDHB were the main metabolites that were enriched in the zebrafish. In the metabolism experiment, the half‐lives of the metabolites were 0.92–1.72 days in zebrafish. The R‐enantiomers of FA and HPPA were preferentially enriched and metabolized with enantiomeric fractions (EFs) of 0.65–0.85. According to the 96‐h acute toxicity, FA, HPPA, EHPP, and CDHB were less toxic to zebrafish than FE, following the order of FE > CDHB > EHPP > FA > HPPA. The S‐enantiomers of FE, FA, CDHB, and EHPP were more toxic than the R‐enantiomers. FE and its metabolites could significantly increase catalase (CAT) and superoxide dismutase (SOD) activity and the malondialdehyde (MDA) content in gill and liver tissues, indicating their oxidative stress, and these effects were also enantioselective. This work could supply more information for evaluating the risks of fenoxaprop‐ethyl on aquatic organisms concerning their metabolites and enantiomers.
Surface Science and Electrochemical Model Studies on the Interaction of Graphite and Li‐Containing Ionic Liquids
Authors: Weber Isabella , Kim Jihyun , Buchner Florian , Schnaidt Johannes , Behm R. Jürgen
Published: March 2020

The process of solid–electrolyte interphase (SEI) formation is systematically investigated along with its chemical composition on carbon electrodes in an ionic liquid‐based, Li‐containing electrolyte in a combined surface science and electrochemical model study using highly oriented pyrolytic graphite (HOPG) and binder‐free graphite powder electrodes (Mage) as model systems. The chemical decomposition process is explored by deposition of Li on a pre‐deposited multilayer film of 1‐butyl‐1‐methylpyrrolidinium bis(trifluoromethylsulfonyl)imide ([BMP][TFSI]) under ultrahigh vacuum conditions. Electrochemical SEI formation is induced by and monitored during potential cycling in [BMP][TFSI]+0.1 m LiTFSI. The chemical composition of the resulting layers is characterized by X‐ray photoelectron spectroscopy (XPS), both at the surface and in deeper layers, closer to the electrode|SEI interface, after partial removal of the film by Ar+ ion sputtering. Clear differences between chemical and electrochemical SEI formation, and also between SEI formation on HOPG and Mage electrodes, are observed and discussed.
Curricular responses to Computer Science provision in schools: current provision and alternative possibilities
Authors: McGarr Oliver , Johnston Keith
Published: March 2020

This paper explores the rationales underpinning the introduction of Computer Science (CS) into school curricula and examines the ways in which educational systems have responded to these growing calls. In outlining the possible ways that educational systems can respond to this demand, the paper makes use of a conceptual framework through which the various possibilities for the provision of CS in school curricula can be categorised. The paper analyses and discusses possible modes of provision identifying the benefits and drawbacks of different approaches. Through this development, the paper aims to raise wider questions about the long‐term positioning of CS within the curriculum and draws particular attention to the need for greater consideration of provision at lower secondary level.
Limbostomy: Longitudinal Intravital Microendoscopy in Murine Osteotomies
Authors: Stefanowski Jonathan , Fiedler Alexander F. , Köhler Markus , Günther Robert , Liublin Wjatscheslaw , Tschaikner Martin , Rauch Ariana , Reismann David , Matthys Romano , Nützi Reto , Bixel Maria Gabriele , Adams Ralf H. , Niesner Raluca A. , Duda Georg N. , Hauser Anja E.
Published: March 2020

Bone healing involves the interplay of immune cells, mesenchymal cells, and vasculature over the time course of regeneration. Approaches to quantify the spatiotemporal aspects of bone healing at cellular resolution during long bone healing do not yet exist. Here, a novel technique termed Limbostomy is presented, which combines intravital microendoscopy with an osteotomy. This design allows a modular combination of an internal fixator plate with a gradient refractive index (GRIN) lens at various depths in the bone marrow and can be combined with a surgical osteotomy procedure. The field of view (FOV) covers a significant area of the fracture gap and allows monitoring cellular processes in vivo. The GRIN lens causes intrinsic optical aberrations which have to be corrected. The optical system was characterized and a postprocessing algorithm was developed. It corrects for wave front aberration‐induced image plane deformation and for background and noise signals, enabling us to observe subcellular processes. Exemplarily, we quantitatively and qualitatively analyze angiogenesis in bone regeneration. We make use of a transgenic reporter mouse strain with nucleargreen fluorescent protein and membrane‐bound tdTomato under the Cadherin‐5 promoter. We observe two phases of vascularization. First, rapid vessel sprouting pervades the FOV within 3–4 days after osteotomy. Second, the vessel network continues to be dynamically remodeled until the end of our observation time, 14 days after surgery. Limbostomy opens a unique set of opportunities and allows further insight on spatiotemporal aspects of bone marrow biology, for example, hematopoiesis, analysis of cellular niches, immunological memory, and vascularization in the bone marrow during health and disease. © 2020 The Authors. Cytometry Part A published by Wiley Periodicals, Inc. on behalf of International Society for Advancement of Cytometry.
Outcomes of patients after successful left ventricular assist device explantation: a EUROMACS study
Authors: Antonides Christiaan F.J. , Schoenrath Felix , de By Theo M.M.H. , Muslem Rahatullah , Veen Kevin , Yalcin Yunus C. , Netuka Ivan , Gummert Jan , Potapov Evgenij V. , Meyns Bart , Özbaran Mustafa , Schibilsky David , Caliskan Kadir ,   the EUROMACS investigators
Published: March 2020

Aims

Sufficient myocardial recovery with the subsequent explantation of a left ventricular assist device (LVAD) occurs in approximately 1–2% of the cases. However, follow‐up data about this condition are scarcely available in the literature. This study aimed to report the long‐term outcomes and clinical management following LVAD explantation.

Methods and results

An analysis of the European Registry for Patients with Mechanical Circulatory Support was performed to identify all adult patients with myocardial recovery and successful explantation. Pre‐implant characteristics were retrieved and compared with the non‐recovery patients. The follow‐up data after explantation were collected via a questionnaire. A Kaplan–Meier analysis for freedom of the composite endpoint of death, heart transplantation, LVAD reimplantion, or heart failure (HF) relapse was conducted. A total of 45 (1.4%) cases with myocardial recovery resulting in successful LVAD explantation were identified. Compared with those who did not experience myocardial recovery, the explanted patients were younger (44 vs. 56 years, P < 0.001), had a shorter duration of cardiac disease (P < 0.001), and were less likely to have ischaemic cardiomyopathy (9% vs. 41.8%, P < 0.001). Follow‐up after explantation could be acquired in 28 (62%) cases. The median age at LVAD implantation was 43 years (inter‐quartile range: 29–52), and 23 (82%) were male. Baseline left ventricular ejection fraction was 18% (inter‐quartile range: 10–20%), and 60.7% of the patients had Interagency Registry for Mechanically Assisted Circulatory Support Profile 1 or 2. Aetiologies of HF were dilated cardiomyopathy in 36%, myocarditis in 32%, and ischaemic in 14% of the patients, and 18% had miscellaneous aetiologies. The devices implanted were HeartMate II in 14 (50%), HVAD in 11 (39%), HeartMate 3 in 2 (7%), and 1 unknown with a median duration of support of 410 days (range: 59–1286). The median follow‐up after explantation was 26 months (range 0.3–73 months), and 82% of the patients were in New York Heart Association Class I or II. Beta‐blockers were prescribed to 85%, angiotensin‐converting enzyme inhibitors to 71%, and loop diuretics to 50% of the patients, respectively. Freedom from the composite endpoint was 100% after 30 days and 88% after 2 years.

Conclusions

The survival after LVAD explantation is excellent without the need for heart transplantation or LVAD reimplantation. Only a minority of the patients suffer from a relapse of significant HF.
A General Convergent Strategy for the Synthesis of Tetra‐Substituted Furan Fatty Acids (FuFAs)
Authors: Wang Yamin , Pritchard Gareth J. , Kimber Marc C.
Published: March 2020

Using a palladium catalyzed ‐ acid mediated isomerization sequence, tetrasubstituted furans suitable for furan fatty acid (FuFA) total synthesis can be effectively constructed in high yield. This convergent approach installs the essential carbon side chains at the α1‐ and α2 ‐positions, the β1‐methyl group, and importantly, an electron withdrawing group at the β2‐position tempering the reactivity of the electron rich furan in the FuFAs. When this EWG is an ester, it was conveniently transformed into the required β1‐methyl group in three high yielding synthetic steps. Using this approach, the total synthesis of 11D5 and 11D3 was accomplished in 7‐steps from commercially available starting materials in overall yields of 52 % and 48 %, respectively. Furthermore, this methodology also provided an efficient synthetic route to the decarboxy analogues of both 11D5 and 11D3.
Cryptic and atypical KMT2A‐USP2 and KMT2A‐USP8 rearrangements identified by mate pair sequencing in infant and childhood leukemia
Authors: Blackburn Patrick R. , Smadbeck James B. , Znoyko Iya , Webley Matthew R. , Pitel Beth A. , Vasmatzis George , Xu Xinjie , Greipp Patricia T. , Hoppman Nicole L. , Ketterling Rhett P. , Baughn Linda B. , Lindsey Kathryn G. , Schandl Cynthia A. , Wolff Daynna J. , Peterson Jess F.
Published: March 2020

Infant leukemias are a rare group of neoplasms that are clinically and biologically distinct from their pediatric and adult counterparts. Unlike leukemia in older children where survival rates are generally favorable, infants with leukemia have a 5‐year event‐free survival rate of <50%. The majority of infant leukemias are characterized by KMT2A (MLL) rearrangements (~70 to 80% in acute lymphoblastic leukemia), which appear to be drivers of early leukemogenesis. In this report, we describe three cases: a 9‐month‐old female infant with B‐acute lymphoblastic leukemia (B‐ALL), an 8‐month‐old female presenting with B/myeloid mixed phenotype acute leukemia (MPAL), and a 16‐month‐old male with B‐ALL. The first case had a normal karyotype and B‐ALL FISH results consistent with an atypical KMT2A rearrangement. The second case had trisomy 10 as the sole chromosomal abnormality and a normal KMT2A FISH result. Case 3 had trisomy 8 and a t(11;15)(q23;q21), an atypical KMT2A rearrangement by FISH studies, and a focal deletion of 15q with a breakpoint within the USP8 gene by chromosomal microarray. Mate pair sequencing was performed on all three cases and identified a KMT2A‐USP2 rearrangement (cases 1 and 2) or a KMT2A‐USP8 rearrangement (case 3). These recently characterized KMT2A fusions have been described exclusively in infant and pediatric leukemia cases where the incidence varies vary according to leukemia subtype, are considered high‐risk, with a high incidence of central nervous system involvement, poor response to initial prednisone treatment, and poor event free survival. Additionally, approximately half of cases are unable to be resolved using standard cytogenetic approaches and are likely under recognized. Therefore, targeted molecular approaches are suggested in genetically unresolved infant leukemia cases to characterize these prognostically relevant clones.
Experimental investigation of desorption kinetics of methane in diesel and internal olefin for enhanced well control
Authors: Ojedeji Damilola , Perry Scott , Nielsen James , Chen Yuanhang
Published: March 2020

Early kick detection and well control decision‐making are more challenging when drilling with nonaqueous drilling fluids, largely due to the poor understanding of mass transfer kinetics of formation gas in and out of nonaqueous drilling fluids during these events. In this study, a laboratory‐scale experimental apparatus was developed and used to experimentally investigate the desorption kinetics of methane in diesel and internal olefin, which are among the most commonly used base fluids for oil‐based muds and synthetic‐based muds, respectively.

Continuous measurements of discharge flow rates and totalized discharge volumes yield extent of desorption over time during each test. A model with a lumped mass transfer coefficient was adopted for describing the desorption process in this study. Experimental methodologies with and without blanket gas were compared and the one without blanket gas was adopted due to its enhanced accuracy and repeatability. Time‐marching analysis was conducted to evaluate the instantaneous desorption coefficient during the entire bubble desorption process, while the maximum instantaneous desorption coefficient was used to characterize each desorption process. The effects of initial saturation pressure and base oil type on the resulting desorption coefficients were studied. According to the experimental results, the maximum instantaneous desorption coefficient is larger in diesel compared to the ones in internal olefins with the same initial saturation pressures. In addition, the maximum instantaneous desorption coefficient increases with initial saturation pressure for both fluids within the range of pressures that were considered in this study. © 2020 Society of Chemical Industry and John Wiley & Sons, Ltd.
Mineralization of the Xuejiping porphyry Cu deposit, Western Yunnan, China: Constraints from magmatic oxidization and source
Authors: Yang Zhen , Fu Yong , Fang Sijie , Xia Peng
Published: March 2020

Xuejiping porphyry Cu deposit is located in the south of Yidun island arc, northwest Yunnan. Tectonically, it lies in the middle part of the “Sanjiang Rivers” metallogenic belts. There are ore‐barren quartz diorite, quartz diorite porphyrite (QDP), and ore‐bearing quartz monzonite porphyry (QMP) intruded into clastic‐volcanic rocks of the late Triassic Tumugou Formation. This study focused on determining why the ore‐bearing porphyry is the QMP. It analyzed the correlation between chronology, geochemistry, magmatic oxygen fugacity, and mineralization. Results show that the crystallization age of QDP is 228.7 Ma and that of QMP is 215.0 Ma, which is relatively younger. The molybdenite Re‐Os age is 219.9 Ma. The oxygen fugacity of QDP and QMP magma are higher than Fayalite‐Magnetite‐Quartz buffer, but the oxygen fugacity value of QDP magma is relatively dispersed, with high and low values. While the QMP falls in the high oxygen fugacity range. The δ18O value of QDP (from 5.66 to 6.27 with an average of 6.02) is higher than that of QMP (from 5.53 to 6.42 with average 5.76). It indicates that the QMP contains more components from the mantle than QDP. It is suggested in this paper that QMP have more potential of ore‐formation in the later stage. The QDP caused ore‐forming elements pre‐enrichment in the region. Millions of years later, the QMP intruded in QDP, the pre‐enriched elements were activated and superimposed with the ore‐forming elements of QMP, then the ore‐forming elements were carried and integrated into the ore deposit, and enriched once again.
Silurian conodont biostratigraphy of the Laojianshan section, Baoshan, Yunnan Province, SW China
Authors: Chen Zhongyang , Männik Peep , Wang Chengyuan , Fang Xiang , Chen Tingen , Ma Xuan , Zhang Yuandong
Published: March 2020

The Baoshan region of Yunnan Province, SW China, is one of the best locations to study Wenlock to Pridoli conodonts in China. Detailed analysis of conodont collections from the Silurian strata (the “Lichaiba” and Niushiping formations) of the Laojianshan section in the Baoshan region resulted in revised dating of the section. In stratigraphically ascending order, the Pterospathodus amorphognathoides amorphognathoides Zonal Group, the Pterospathodus pennatus procerus Superbiozone (probably only the Lower Pterospathodus pennatus procerus Biozone), the Ozarkodina sagitta sagitta Biozone, the Kockelella ortus absidata Biozone, the Kockelella crassa Biozone, the Polygnathoides siluricus Biozone and the “Ozarkodina” eosteinhornensis s.l. Interval Biozone are recognised. The conodont faunas recovered indicate that the “Lichaiba Formation” corresponds to the upper Telychian–upper Wenlock, and the Niushiping Formation to the Ludlow–Pridoli. Part of the Ireviken Event, that is, from Datum 3 to Datum 4 can be recognised from the studied section. The late Telychian conodont fauna from the Laojianshan section is characteristic of distal, open‐shelf depositional environments.
Expert consensus for managing pregnant women and neonates born to mothers with suspected or confirmed novel coronavirus (COVID‐19) infection
Authors: Chen Dunjin , Yang Huixia , Cao Yun , Cheng Weiwei , Duan Tao , Fan Cuifang , Fan Shangrong , Feng Ling , Gao Yuanmei , He Fang , He Jing , Hu Yali , Jiang Yi , Li Yimin , Li Jiafu , Li Xiaotian , Li Xuelan , Lin Kangguang , Liu Caixia , Liu Juntao , Liu Xinghui , Pan Xingfei , Pang Qiumei , Pu Meihua , Qi Hongbo , Shi Chunyan , Sun Yu , Sun Jingxia , Wang Xietong , Wang Yichun , Wang Zilian , Wang Zhijian , Wang Chen , Wu Suqiu , Xin Hong , Yan Jianying , Zhao Yangyu , Zheng Jun , Zhou Yihua , Zou Li , Zeng Yingchun , Zhang Yuanzhen , Guan Xiaoming
Published: March 2020

Objective

To provide clinical management guidelines for novel coronavirus (COVID‐19) in pregnancy.

Methods

On February 5, 2020, a multidisciplinary teleconference comprising Chinese physicians and researchers was held and medical management strategies of COVID‐19 infection in pregnancy were discussed.

Results

Ten key recommendations were provided for the management of COVID‐19 infections in pregnancy.

Conclusion

Currently, there is no clear evidence regarding optimal delivery timing, the safety of vaginal delivery, or whether cesarean delivery prevents vertical transmission at the time of delivery; therefore, route of delivery and delivery timing should be individualized based on obstetrical indications and maternal–fetal status.
Investigation of the effects of laminin present in the basal lamina of the peripheral nervous system on axon regeneration and remyelination using the nerve acellular scaffold
Authors: Ji Wanqing , Hou Bo , Tang Hengxin , Cai Meiqin , Zheng Wenhan
Published: March 2020

This study aimed to investigate the effects of laminin (LN) located in the basal lamina, which are important components of the peripheral nervous system‐extracellular matrix, on axon regeneration and remyelination. Nerve acellular scaffolds (NASs) (S‐untreated) were prepared using the acellular technique. The active component LN in the NASs was blocked (S‐LN−) or upregulated (S‐LN+); S‐LN+ contained seven times more LN than did the S‐untreated group. The adhesion capacity of Schwann cells (SCs) to the three types of NAS (S‐untreated, S‐LN−, and S‐LN+) was assessed in vitro. Our results showed that the adhesion of SCs to the NASs was significantly reduced in the S‐LN− group, whereas no difference was observed between the S‐LN+ and S‐untreated groups. The pretreated NASs were used to repair nerves in a nerve injury mouse model with the animals divided into four groups (S‐LN− group, S‐untreated group, S‐LN+ group, and autograft group). Two weeks after surgery, although there was no difference in the S‐LN− group, S‐untreated group and S‐LN+ group, the newly formed basal lamina in the S‐LN− group were significantly lower than those in the other two groups. Four weeks after surgery, the S‐LN+ group had higher numbers of newly generated axons and their calibers, more myelinated fibers, thicker myelin sheaths, increased myelin basic protein expression, and improved recovery of neural function compared to those of the S‐LN− and S‐untreated groups, but all of these parameters were significantly worse than those of the autograft group. Downregulation of the LN level in the NAS leads to a reduction in all of the above parameters.
Resveratrol for protection against statin toxicity in C2C12 and H9c2 cells
Authors: Attalah nee Rezkallah Chama , Thongkum Angkana , Zhu Chao , Chen Qin M.
Published: March 2020

Statins are among the most commonly prescribed drugs for the treatment of high blood cholesterol. Myotoxicity of statins in certain individuals is often a severe side effect leading to withdrawal. Using C2C12 and H9c2 cells, both exhibiting characteristics of skeletal muscle cells, we addressed whether resveratrol (RSV) can prevent statin toxicity. Statins decreased cell viability in a dose and time‐dependent manner. Among the five statins tested, atorvastatin, simvastatin, lovastatin, pravastatin, and fluvastatin, simvastatin is the most toxic one. Simvastatin at 10 µM caused about 65% loss of metabolic activity as measured by 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide assays in C2C12 cells or H9c2 cells. Inhibition of metabolic activity correlates with an increase in caspase activity. RSV was found to protect H9c2 cells from simvastatin‐induced activation of caspase‐3/7. However, such protection was not found in C2C12 cells. This cell type‐dependent effect of RSV adds to the complexity in muscle cell toxicity of statins.
Inhibitors of Organic Anion‐Transporting Polypeptides 1B1 and 1B3: Clinical Relevance and Regulatory Perspective
Authors: McFeely Savannah J. , Ritchie Tasha K. , Yu Jingjing , Nordmark Anna , Berglund Eva Gil , Levy Rene H. , Ragueneau‐Majlessi Isabelle
Published: March 2020

Organic anion‐transporting polypeptides (OATPs) 1B1 and 1B3 are the primary hepatic transporters responsible for uptake of drugs into the liver and, as such, an area of growing research focus. Currently, evaluation of these transporters as potential mediators of drug‐drug interactions (DDIs) is recommended by regulatory agencies worldwide during the drug development process. Despite the growing focus on OATP1B1/1B3 as mediators of DDIs, only 2 drugs are recommended as index inhibitors for use in clinical studies, single‐dose rifampin and cyclosporine, each with limitations for the utility of the resulting data. In this study a thorough analysis of the available in vitro and clinical data was conducted to identify drugs that are clinically relevant inhibitors of OATP1B1/1B3 and, from those, to select any novel index inhibitors. A total of 13 drugs and 16 combination products were identified as clinical inhibitors of OATP1B1/1B3, showing significant changes in exposure for sensitive substrates of the transporters, with strong supporting in vitro evidence. Although none of the identified inhibitors qualified as index inhibitors, this study confirmed the utility of cyclosporine and single‐dose rifampin as index inhibitors to evaluate the effect of broad, multiple‐pathway inhibition and more selective OATP1B1/1B3 inhibition, respectively.
A synoptic climatology of potential seiche‐inducing winds in a large intermontane lake: Quesnel Lake, British Columbia, Canada
Authors: Thompson Hadleigh D. , Déry Stephen J. , Jackson Peter L. , Laval Bernard E.
Published: March 2020

Excitation of basin‐scale, internal waves (i.e., internal seiches) in lakes require spatially homogeneous wind fields that vary on time scales comparable to the seiche period, which can be on the order of several days in large lakes. We evaluate 2 years (October 1, 2016 to September 30, 2018) of 15‐min wind data from a shore‐based meteorological station to identify strong wind episodes likely to excite internal seiches in a large and geometrically complex lake surrounded by convoluted topography, Quesnel Lake, British Columbia, Canada. Our findings include the identification of strong wind event seasonality, with peak mean monthly wind speeds in April and November, and minimum mean monthly wind speeds in August. Using geopotential heights (GPHs) from 1.5° × 1.5° gridded reanalysis data to reconstruct the atmospheric state for each strong wind episode, two primary synoptic patterns are identified that, in conjunction with local topographic channelling, lead to either easterlies or westerlies occurring at our sampling station, with strong easterly episodes three times more frequent than westerly episodes. This highlights the important role that developing low‐pressure systems in the Northeastern Pacific Basin have in setting up the GPH gradient required for persistent strong winds at Quesnel Lake, in the hours and days before these storms make landfall. The projection of synoptic patterns of strong wind events onto a 4 × 3 self‐organizing map clustered strong wind events by mean wind direction, similar to the results of a manual classification. Methods to identify the strong wind episodes and the resulting self‐organizing map are both evaluated in‐part by two case studies where strong winds are known to have excited a basin‐scale baroclinic response in Quesnel Lake.
Self‐Assembly of Supramolecular DNA Amphiphiles through Host–Guest Interaction and Their Stimuli‐Responsiveness
Authors: Yuan Wei , Ma Jiahui , Zhao Zhiyong , Liu Simin
Published: March 2020

Smart DNA nanostructures have found potential application in material science and biomedicine. Most building blocks are DNA amphiphiles covalently synthesized from DNA and hydrophobic molecules. Here, the noncovalent approach based on the host–guest interaction between cucurbit[7]uril (CB[7]) and two hydrophobic guests with different topologies is utilized to modularly construct supramolecular DNA amphiphiles including DNA‐CB[7]/ferrocene derivative and DNA‐CB[7]/adamantine derivative. Both of the supramolecular DNA amphiphiles assemble into uniform spherical micelles, which can encapsulate hydrophobic Nile Red molecules and anchor gold nanoparticles through DNA hybridization. In addition, 1‐adamantanamine hydrochloride, a competitive guest with a strong binding constant with CB[7], induces the dissociation of DNA‐CB[7]/ferrocene derivative micelles. More importantly, the redox properties of ferrocene induce reversible morphology changes between the spherical micelles and the dissociated state. These stimuli‐responsive DNA supra‐amphiphilic micelles, as novel vehicles, expand the family of smart DNA nanostructures.
A critical commentary on the proposals to reform India's financial system in its 2019–20 union budget
Authors: Chakraborty Gourab
Published: March 2020

The 2019–20 Union budget aims to signal that the economic gains from cleaning of the financial system are likely to be recognizable in the future. The non‐performing assets in commercial banks have dropped substantively in last year subsequent to unprecedented recoveries over the past 4 years due to Insolvency and Bankruptcy Code and other legal measures, provision coverage ratio is now at its highest in 7 years, and domestic credit growth has risen to 13.8%. The government has smoothly carried out the consolidation of public sector banks. However, the drop in banks' NPAs appears to be reflected by a liquidity squeeze and mirrored by mounting NPAs confronting the non‐banking finance company (NBFC). In addition, the problems are acute for the analyzed sub‐group of Housing Finance Corporations. While the government has announced its decision to streamline the regulatory processes within this sub‐sector, it has mandated the banks, the chief source of funds to mobilize capital for the NBFCs that appear vital to revive India's economic growth. The government has raised tax rates for the uber‐rich and import duties on a few articles such as Gold while offering tax credits on affordable housing and electric vehicles. It has attempted to improve the microstructure of the capital markets, mitigate inefficiencies in the pension space and enhance market penetration of insurance and incentivize foreign investment through budgetary proposals. This article offers a critical commentary on the proposed policy actions.
Does corporate governance affect CEO compensation in Indian manufacturing firms?
Authors: Patnaik Pooja , Suar Damodar
Published: March 2020

This study examines the effects of (a) chief executive officers (CEO) pay dynamics, (b) corporate governance characteristics, and (c) the impact of environmental, social, and governance disclosure practices on CEO compensation. Data of 282 Indian manufacturing firms were collected from Bloomberg database from 2013–14 to 2018–19. This study uses Generalized Method of Moments estimation technique to assess the impact of corporate governance on CEO compensation. The empirical estimates reveal that increase in board size, board independence, women director in board, CEO duality, and institutional holdings reduced CEO compensation. Furthermore, the environmental, social, and governance disclosure confirmed that higher firm disclosures help to streamline CEO compensation. It has also been found that CEOs' current compensation is affected by their previous pay. This study corroborates the objectives of Companies Act 2013 to streamline the governance practices for optimizing CEO compensation.
The impact of generic aromatase inhibitors on initiation, adherence, and persistence among women with breast cancer: Applying multi‐state models to understand the dynamics of adherence
Authors: Winn Aaron N. , Fergestrom Nicole M. , Pezzin Liliana E. , Laud Purushottam W. , Neuner Joan M.
Published: March 2020

Purpose

Clinical trials have clearly documented the survival benefit of aromatase inhibitors (AIs); however, many women fail to initiate (primary nonadherence) or remain adherent to AIs (secondary nonadherence). Prior studies have found that costs impact secondary nonadherence to medications but have failed to examine primary nonadherence. The purpose of this study is to examine primary and secondary adherence following the reduction in copays due to the introduction of generic AIs.

Methods

Using Surveillance, Epidemiology, and End Results‐Medicare data, we identified 50 054 women diagnosed with incident breast cancer between 2008 and 2013. We compare women whose copays would change and those whose would not, due to the receipt of cost‐sharing subsidies before and after generics were introduced using a difference‐in‐difference (DinD) analysis. To examine primary and secondary nonadherence, we rely on a multistate model with four states (Not yet initiated, User, Not Using, and Death). We adjusted for baseline factors using inverse probability treatment weights and then simulated adherence for 36 months following diagnosis.

Results

The generic introduction of AIs resulted in patients initiating AIs faster (DinD = −4.7%, 95%CI = −7.0, −2.3; patients not yet initiating treatment at 6‐months), being more adherent (DinD ranging in absolute increase of 8.1%‐10.4%) and being less likely to not be using the therapy (DinD range in absolute decrease of 1.2% at 6 months to 8.8% at 24 months) for women that do not receive a subsidy after generics were available.

Conclusions

Introduction of generic alternatives to AIs significantly reduced primary and secondary nonadherence.