bluuebunny/crossref_metadata_2025_split huggingface dataset:
Soil acidification in a continuous cotton production system
Authors: Ghimire Rajan , Parajulee Megha N. , Acharya Pramod , Dhakal Dol P. , Hakeem Abdul , Lewis Katie L. 
Published: June 2021

AbstractEffects of nitrogen (N) fertilization on soil organic carbon (SOC) and total N are well established, but their effects on soil acidification and emerging soil health indicators such as labile N and carbon (C) pools are not adequately documented. This research evaluated soil N and C pools and soil pH with long‐term N management in continuous cotton (Gossypium hirsutum L.) production. Residual soil inorganic N, potentially mineralizable N and C, total N, SOC, pH, and electrical conductivity were measured after 17 yr of continuous N application. Comparison of five N rates (0, 56, 112, 168, and 224 kg ha–1) showed an increase in residual inorganic N pools and decrease in pH with an increase in N application rate, while other parameters did not change significantly. Soil acidification was significant with 168 and 224 kg N ha–1 rates. Soil pH dropped by 0.039 per kilogram increase in residual inorganic N. Optimizing N rate that minimizes residual inorganic N can reduce soil acidification.
Highly Enantioselective Iridium(I)‐Catalyzed Hydrocarbonation of Alkenes: A Versatile Approach to Heterocyclic Systems Bearing Quaternary Stereocenters
Authors: Arribas Andrés , Calvelo Martín , Fernández David F. , Rodrigues Catarina A. B. , Mascareñas José L. , López Fernando 
Published: June 2021

AbstractWe report a versatile, highly enantioselective intramolecular hydrocarbonation reaction that provides a direct access to heteropolycyclic systems bearing chiral quaternary carbon stereocenters. The method, which relies on an iridium(I)/bisphosphine chiral catalyst, is particularly efficient for the synthesis of five‐, six‐ and seven‐membered fused indole and pyrrole products, bearing one and two stereocenters, with enantiomeric excesses of up to >99 %. DFT computational studies allowed to obtain a detailed mechanistic profile and identify a cluster of weak non‐covalent interactions as key factors to control the enantioselectivity.
Successive Storage of Cations and Anions by Ligands of π–d‐Conjugated Coordination Polymers Enabling Robust Sodium‐Ion Batteries
Authors: Chen Yuan , Zhu Qin , Fan Kun , Gu Yuming , Sun Mingxuan , Li Zengyu , Zhang Chenyang , Wu Yanchao , Wang Qian , Xu Shuaifei , Ma Jing , Wang Chengliang , Hu Wenping 
Published: June 2021

AbstractThe oxidation of π–d‐conjugated coordination polymers (CCPs) accompanied with anion insertion has the merits of increasing the capacity and elevating the discharge voltages. However, previous reports on this mechanism either required more investigations or showed low capacity and poor cyclablity. Herein, triphenylene‐catecholate‐based two‐dimensional CCPs are constructed by employing inactive transition‐metal ions (Zn2+) as nodes, forming Zn‐HHTP. Substantial characterizations and theoretical calculations indicate the successive storage of cations and anions by redox reactions of only ligands, leading to a high reversible capacity of ≈150 mAh g−1 at 100 mA g−1 and a remarkable capacity retention of 90 % after 1000 cycles. On the contrary, as a control experiment, the analogous CCPs (Cu‐HHTP) with Cu2+ nodes, where both ligands and metal ions undergo redox reactions, accompanied by the storage of only Na+ cations, show a much poorer cyclability. These results highlight the importance of redox reactions of only ligands for long‐term cycle life and the insight into the storage mechanisms deepens our understanding on CCPs for the further design of CCPs with high performance.
Photoelektronen‐Zirkulardichroismus im Photodetachment von Aminosäuren‐Anionen
Authors: Krüger Peter , Weitzel Karl‐Michael 
Published: June 2021

AbstractDie Chiralität chemischer Verbindungen ist in Wissenschaft und Technik von unumstrittener Bedeutung. Insbesondere im Hinblick auf pharmazeutische Anwendungen sind jedoch viele Moleküle von Interesse, die mit den leistungsfähigen Methoden, welche in den letzten Jahren für Analyten in der Gasphase entwickelt wurden, nicht untersucht werden können. Hier zeigen wir, dass die Kombination der Elektrosprayionisation (ESI) mit der Detektion des Photoelektronen‐Zirkulardichroismus (PECD) Zugang zu Chiralitätsinformationen molekularer Materialien mit vernachlässigbarem Dampfdruck, z. B. Aminosäuren, bietet. Zu diesem Zweck wurden Glutaminsäure und 3,4‐Dihydroxyphenylalanin (DOPA) mittels ESI in ein Chiralitätsspektrometer überführt, in welchem Photodetachment ausgelöst und der PECD detektiert wird. Es ist zu erwarten, dass diese Technik konzeptionell auf alle chemischen Systeme anwendbar ist, deren Chiralität auf molekularen Eigenschaften basiert.
Site‐ and Enantioselective Iridium‐Catalyzed Desymmetric Mono‐Hydrogenation of 1,4‐Dienes
Authors: Wu Haibo , Su Hao , Schulze Erik J. , Peters Bram B. C. , Nolan Mark D. , Yang Jianping , Singh Thishana , Ahlquist Mårten S. G. , Andersson Pher G. 
Published: June 2021

AbstractThe control of site selectivity in asymmetric mono‐hydrogenation of dienes or polyenes remains largely underdeveloped. Herein, we present a highly efficient desymmetrization of 1,4‐dienes via iridium‐catalyzed site‐ and enantioselective hydrogenation. This methodology demonstrates the first iridium‐catalyzed hydrogenative desymmetriation of meso dienes and provides a concise approach to the installation of two vicinal stereogenic centers adjacent to an alkene. High isolated yields (up to 96 %) and excellent diastereo‐ and enantioselectivities (up to 99:1 d.r. and 99 % ee) were obtained for a series of divinyl carbinol and divinyl carbinamide substrates. DFT calculations reveal that an interaction between the hydroxy oxygen and the reacting hydride is responsible for the stereoselectivity of the desymmetrization of the divinyl carbinol. Based on the calculated energy profiles, a model that simulates product distribution over time was applied to show an intuitive kinetics of this process. The usefulness of the methodology was demonstrated by the synthesis of the key intermediates of natural products zaragozic acid A and (+)‐invictolide.
Sequential Continuous‐Flow Synthesis of 3‐Aryl Benzofuranones
Authors: Xin Hai‐Long , Rao Xiaofeng , Ishitani Haruro , Kobayashi Shū 
Published: June 2021

AbstractA sequential continuous‐flow system to produce 3‐aryl benzofuranones was developed. Starting from 2,4‐di‐tert‐butylphenol and glyoxylic acid monohydrate, both the initial cyclocondensation and the subsequent Friedel−Crafts alkylation were catalyzed by the same heterogeneous catalyst, Amberlyst‐15H. The catalyst has a promising life‐time for these two steps, and it was able to be recovered and reused for several runs without deactivation. By using the established flow system, 5,7‐di‐tert‐butyl‐3‐(3,4‐dimethylphenyl)‐3H‐benzofuran‐2‐one (Irganox HP‐136), which is a commercial antioxidant, was prepared in 88% two‐step yield. Reactions with various aromatic compounds proceeded well under flow conditions to afford 3‐aryl benzo‐furanone derivatives in high yields with good functional group compatibility.
Multicomponent Bioluminescence Imaging with Naphthylamino Luciferins
Authors: Brennan Caroline K. , Ornelas Marya Y. , Yao Zi W. , Prescher Jennifer A. 
Published: June 2021

AbstractBioluminescent tools have been used for decades to image processes in complex tissues and preclinical models. However, few distinct probes are available to probe multicellular interactions. We and others are addressing this limitation by engineering new luciferases that can selectively process synthetic luciferin analogues. In this work, we explored naphthylamino luciferins as orthogonal bioluminescent probes. Three analogues were prepared using an optimized synthetic route. The luciferins were found to be robust emitters with native luciferase in vitro and in cellulo. We further screened the analogues against libraries of luciferase mutants to identify unique enzyme‐substrate pairs. The new probes can be used in conjunction with existing bioluminescent tools for multi‐component imaging.
Percutaneous artErial closure devices and ultrasound‐guided Trans‐femoRal puncture ObservatioNal InvestigatiOn: Insights from the PETRONIO registry
Authors: Iannopollo Gianmarco , Nobile Giampiero , Lanzilotti Valerio , Capecchi Alessandro , Verardi Roberto , Bruno Matteo , Somaschini Alberto , Rubboli Andrea , Di Pasquale Giuseppe , Casella Gianni 
Published: June 2021

AbstractObjectiveTo evaluate the safety of a single and combined use of ultrasound‐guided femoral puncture (U) and percutaneous arterial closure devices (P) in femoral artery procedures (FAP) compared to fluoroscopic guidance (F) and manual compression (M) in a large radial‐focused interventional centre.BackgroundU and P, taken individually, have improved safety in femoral arterial access procedures compared to traditional techniques.MethodsAll FAP performed between July 2017 and December 2018 in our centre were divided into three phases: (a) control period with F and M mainly performed; (b) phase out period where U and P were introduced; (c) intervention period where a 6‐month expertise on the novel techniques was acquired. The overall population was further stratified into subgroups: F/M, U/M, F/P, U/P. The primary study endpoint was in‐hospital access site bleeding events (BE) according to the BARC criteria. The secondary endpoint was vascular site complications (VASC).ResultsFour hundred eighteen procedures (14%) out of 3025 were performed via FA access during the study period. The overall access‐site in‐hospital BE were 97 (23%). Decreasing rates of BE (phase 1: n = 46, 29%; phase 2: n = 38, 22% e phase 3: n = 13, 15%; p = 0.027) and VASC were observed during the three periods. BE occurred significantly more often in F/M group (F/M: n = 48; 32%; U/M: n = 12, 16%; F/P: n = 18, 21%; U/P: n = 19, 17%; p = 0.008). F/M subgroup was an independent predictor of BE both in multivariable analysis and propensity score matching analysis.ConclusionsThe introduction of ultrasound‐guided femoral puncture and percutaneous arterial closure devices has reduced access site bleedings with a progressive improvement after the first 6 months learning period.
Paired and Tandem Electrochemical Conversion of 5‐(Hydroxymethyl)furfural Using Membrane‐Electrode Assembly‐Based Electrolytic Systems
Authors: Liu Hengzhou , Lee Ting‐Han , Chen Yifu , Cochran Eric W. , Li Wenzhen 
Published: June 2021

AbstractPairing the electrocatalytic hydrogenation (ECH) reaction with different anodic reactions holds great promise for producing value‐added chemicals driven by renewable energy sources. Replacing the sluggish water oxidation with a bio‐based upgrading reaction can reduce the overall energy cost and allows for the simultaneous generation of high‐value products at both electrodes. Herein, we developed a membrane‐electrode assembly (MEA)‐based electrolysis system for the conversion of 5‐(hydroxymethyl)furfural (HMF) to bis(hydroxymethyl)furan (BHMF) and 2,5‐furandicarboxylic acid (FDCA). With (2,2,6,6‐tetramethylpiperidin‐1‐yl)oxyl (TEMPO)‐mediated electrochemical oxidation (ECO) of HMF at the anode, the unique zero‐gap configuration enabled a minimal cell voltage of 1.5 V at 10 mA, which was stable during a 24‐hour period of continuous electrolysis, resulting in a combined faradaic efficiency (FE) as high as 139 % to BHMF and FDCA. High FE was also obtained in a pH‐asymmetric mediator‐free configuration, in which the ECO was carried out in 0.1 M KOH with an electrodeposited NiFe oxide catalyst and a bipolar membrane. Taking advantage of the low cell resistance of the MEA‐based system, we also explored ECH of HMF at high current density (280 mA cm−2), in which a FE of 24 % towards BHMF was achieved. The co‐generated H2 was supplied into a batch reactor in tandem for the catalytic hydrogenation of furfural or benzaldehyde under ambient conditions, resulting in an additional 7.3 % of indirect FE in a single‐pass operation. The co‐electrolysis of bio‐derived molecules and the tandem electrocatalytic‐catalytic process provide sustainable avenues towards distributed, flexible, and energy‐efficient routes for the synthesis of valuable chemicals.
Iron‐Catalyzed Halogen Exchange of Trifluoromethyl Arenes**
Authors: Dorian Andreas , Landgreen Emily J. , Petras Hayley R. , Shepherd James J. , Williams Florence J. 
Published: June 2021

AbstractThe facile production of ArCF2X and ArCX3 from ArCF3 using catalytic iron(III)halides is reported, which constitutes the first iron‐catalyzed halogen exchange for non‐aromatic C−F bonds. Theoretical calculations suggest direct activation of C−F bonds by iron coordination. ArCX3 and ArCF2X products of the reaction are synthetically valuable due to their diversification potential. In particular, chloro‐ and bromodifluoromethyl arenes (ArCF2Cl, ArCF2Br respectively) provide access to a myriad of difluoromethyl arene derivatives (ArCF2R). To optimize for mono‐halogen exchange, a statistical method called Design of Experiments was used. Optimized parameters were successfully applied to electron rich and electron deficient aromatic substrates, and to the late stage diversification of flufenoxuron, a commercial insecticide. These methods are highly practical, being run at convenient temperatures and using inexpensive common reagents.
Janus Pyrrolopyrrole Aza‐dipyrrin: Hydrogen‐Bonded Assemblies and Slow Magnetic Relaxation of the Cobalt(II) Complex in the Solid State
Authors: Ishizaki Toshiharu , Karasaki Hideaki , Kage Yuto , Kamioka Misaki , Wang Yitong , Mori Shigeki , Ishikawa Naoto , Fukuda Takamitsu , Furuta Hiroyuki , Shimizu Soji 
Published: June 2021

AbstractA novel pyrrolopyrrole azadipyrrin (Janus‐PPAD) with Janus duality was synthesized by a Schiff base–forming reaction of diketopyrrolopyrrole. The orthogonal interactions of the hydrogen‐bonding ketopyrrole and metal‐coordinating azadipyrrin moieties in Janus‐PPAD enabled the metal ions to be arranged at regular intervals: zinc(II) and cobalt(II) coordination provided metal‐coordinated Janus‐PPAD dimers, which can subsequently form hydrogen‐bonded one‐dimensional arrays both in solution and in the solid state. The supramolecular assembly of the zinc(II) complex in solution was investigated by 1H NMR spectroscopy based on the isodesmic model, in which a binding constant for the elongation of assemblies is constant. Owing to the tetrahedral coordination, in the solid state, the cobalt(II) complex exhibited a slow magnetic relaxation due to the negative D value of −27.1 cm−1 with an effective relaxation energy barrier Ueff of 38.0 cm−1. The effect of magnetic dilution on the relaxation behavior is discussed. The relaxation mechanism at low temperature was analyzed by considering spin lattice interactions and quantum tunneling effects. The easy‐axis magnetic anisotropy was confirmed, and the relevant wave functions were obtained by ab initio CASSCF calculations.
Insights from Binding on Quadruplex Selective Carbazole Ligands
Authors: Müller Diana , Saha Puja , Panda Deepanjan , Dash Jyotirmayee , Schwalbe Harald 
Published: June 2021

AbstractPolymorphic G‐quadruplex (G4) secondary DNA structures have received increasing attention in medicinal chemistry owing to their key involvement in the regulation of the maintenance of genomic stability, telomere length homeostasis and transcription of important proto‐oncogenes. Different classes of G4 ligands have been developed for the potential treatment of several human diseases. Among them, the carbazole scaffold with appropriate side chain appendages has attracted much interest for designing G4 ligands. Because of its large and rigid π‐conjugation system and ease of functionalization at three different positions, a variety of carbazole derivatives have been synthesized from various natural or synthetic sources for potential applications in G4‐based therapeutics and biosensors. Herein, we provide an updated close‐up of the literatures on carbazole‐based G4 ligands with particular focus given on their detailed binding insights studied by NMR spectroscopy. The structure‐activity relationships and the opportunities and challenges of their potential applications as biosensors and therapeutics are also discussed. This review will provide an overall picture of carbazole ligands with remarkable G4 topological preference, fluorescence properties and significant bioactivity; portraying carbazole as a very promising scaffold for assembling G4 ligands with a range of novel functional applications.
STING pathway expression in low‐grade serous carcinoma of the ovary: an unexpected therapeutic opportunity?
Authors: Huvila Jutta , Cochrane Dawn R , Ta Monica , Chow Christine , Greening Kendall , Leung Samuel , Karnezis Anthony N , DiFeo Analisa , Huntsman David G 
Published: June 2021

AbstractOvarian carcinoma histotypes are distinct diseases with variable clinical outcomes and response to treatment. There is a need for new subtype‐specific treatment modalities, especially for women with widespread and chemo‐resistant disease. Stimulator of interferon genes (STING) is a part of the cGAS–STING pathway that mediates innate immune defence against infectious DNA‐containing pathogens and also detects tumour‐derived DNA and generates intrinsic antitumour immunity. The STING signalling pathway is suppressed by several mechanisms in a variety of malignant diseases and, in some cancers that may be a requirement for cellular transformation. The aim of this study was to use immunohistochemistry to evaluate STING protein expression across normal tissue, paratubal and ovarian cysts, and ovarian tumour histotypes including ovarian carcinomas. Herein, we show that the fallopian tube ciliated cells express STING protein, whereas the secretory cells are negative. STING expression differs among ovarian cancer histotypes; low‐grade serous ovarian carcinomas and serous borderline tumours have uniform high STING expression, while high‐grade serous and endometrioid carcinomas have heterogeneous expression, and clear cell and mucinous carcinomas show low expression. As low‐grade serous carcinomas are known to be genomically stable and typically lack a prominent host immune response, the consistently high STING expression is unexpected. High STING expression may reflect pathway activation or histogenesis and the mechanisms may be different in different ovarian carcinoma histotypes. Further studies are needed to determine whether the STING signalling pathway is active and whether these tumours would be candidates for therapeutic interventions that trigger innate immunity activation.
Efficacy and safety of transvenous lead extraction in the Chinese octogenarian patients
Authors: Zhou Xu , Ze Feng , Li Xuebin , Wang Bin 
Published: June 2021

AbstractBackgroundManaging elderly patients with infection or malfunction deriving from a cardiac implantable electronic device (CIED) may be challenging. We report the safety and effectiveness of transvenous lead extraction in Chinese octogenarian patients.HypothesisTransvenous lead extraction can be performed safely and successfully in the Chinese octogenarians.MethodsWe retrospectively identified all patients who underwent TLE at our institution between March 2013 and January 2021. This population was divided into the following two groups based solely on age: octogenarians and non‐octogenarians. These two groups were compared on the basis of several characteristics and clinical outcomes.ResultsConsecutive 1106 patients were analyzed, including 184 (16.6%) octogenarians and 922(83.4%) non‐octogenarians. The octogenarians presented more comorbidities. A total of 378 leads and 2004 leads were removed from the patients in the octogenarian group and non‐octogenarian group, respectively. The mean lead implant duration was 6.1 ± 5.1 and 5.8 ± 4.6 years for octogenarians and non‐octogenarians (p = 0.296). The majority of the patients in both groups underwent TLE through the femoral approach (67.5% vs 61.6%, p = 0.14). The complete procedure success rate was similar between the octogenarian and non‐octogenarian group (96.7% vs.95.3%, p = 0.39). There were no differences with respect to the proportion of minor, major complications and deaths. Long‐term mortality (median time 3.3 years) after TLE in octogenarians was significantly higher compared with younger individuals.ConclusionsAt experienced centers, transvenous lead extraction can be performed safely in Chinese octogenarians with procedural success rate and complication rate comparable to younger individuals.
Production of Structured RNA Fragments by In Vitro Transcription and HPLC Purification
Authors: Karlsson Hampus , Feyrer Hannes , Baronti Lorenzo , Petzold Katja 
Published: June 2021

AbstractThe understanding of the functional importance of RNA has increased enormously in the last decades. This has required research on the RNA molecules themselves, with the concomitant need for obtaining purified RNA samples, such as for structural studies by NMR or other methods. The main method to create labeled and unlabeled RNA, T7 in vitro transcription, suffers from sequence‐dependent yield and often low homogeneity for short constructs (<100 nt) and requires laborious purification. Additionally, the design of structured RNA fragments mimicking the structure of a larger biological RNA is often not straightforward. Secondary structure simulations can be used to make reliable predictions about the folding of a particular RNA fragment. In this article, we describe how to design an RNA construct of interest from a larger sequence, and we combine several previously published improvements of the in vitro transcription method, such as the use of 2′‐methoxy modifications and dimethyl sulfoxide or the use of tandem repeats, to increase yield and purity of in vitro–transcribed RNA. Together with a high‐performance liquid chromatography (HPLC) purification procedure using both reversed‐phase ion‐pairing and ion‐exchange HPLC, we provide a robust protocol to obtain highly pure RNA of short to intermediate length in large quantities. The protocol optimizes yield, especially for RNA starting with nucleotides other than G. At the same time, it is simplified, and the required time is reduced. The protocols described here constitute a versatile pipeline for the production of purified RNA samples and are suitable for users with little experience in liquid chromatography. © 2021 The Authors.Basic Protocol 1: RNA construct designBasic Protocol 2: DNA template production and in vitro transcriptionAlternate Protocol: Tandem transcription and RNase H cleavageBasic Protocol 3: Reversed‐phase ion‐pairing HPLC purificationBasic Protocol 4: Ion‐exchange HPLC purification
A case series of CBT‐T in routine clinical practice
Authors: Rose Charlotte , Bakopoulou Ioanna , Novak Tamas 
Published: June 2021

AbstractObjectiveCBT‐T is a relatively new, brief cognitive behavioral therapy eating disorder treatment for non‐underweight patients. This study evaluates CBT‐T independently from the team that developed the protocol, and examines the relationship between eating disorder duration and CBT‐T effectiveness.MethodA case series design was used, comprising N = 40 adults with bulimia or atypical anorexia type eating disorders. CBT‐T was delivered by CBT therapists in a specialist outpatient service. Mixed model analysis examined the interactions between eating disorder duration and change to eating disorder psychopathology and secondary impairment from pre‐post treatment. Abstinence, good outcome, and remission rates were also provided.ResultsIntervention effect sizes were large. Treatment completers reported abstinence from binge eating and purging over the final 28‐days, and 7‐days of treatment at 30.1%, and 73.1%, respectively; 76.9% reported good outcome; and 23.1% reported remission. No relationship between eating disorder duration and treatment effectiveness was found.DiscussionThese findings build on existing evidence supporting provision of CBT‐T in routine clinical practice, for patients with eating disorders of any duration. Replication, extension, and RCT will strengthen comparability with other evidence‐based approaches.