bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthese von Carbazolen und Verwandten Heterocyclen aus Sulfiliminen durch Intramolekulare C‐H‐Aminierungen
Authors: Tian Xianhai , Song Lina , Hashmi A. Stephen K. 
Published: February 2020

AbstractWährend sich direkte Nitren‐Insertionen in C‐H‐Bindungen zu einem wichtigen Werkzeug für die C‐N‐Bindungsknüpfung in der modernen organischen Chemie entwickelt haben, erfordert die Generierung von Nitren‐Zwischenstufen meist Übergangsmetall‐Katalysatoren, hohe Temperaturen, UV‐ oder Laserlicht. Wir berichten über eine milde Synthese von Carbazolen und verwandte Bausteine durch eine von sichtbarem Licht induzierte intramolekulare C‐H‐Aminierungs‐Reaktion. Ein wichtiger Vorteil dieser neuen Methode ist die Nutzung der reaktiveren Arylsulfilimine anstelle der korrespondierenden gefährlichen Azide. Verschiedene Katalysatoren und verschiedenste Lichtquellen wurden getestet. Die Reaktion kann breit angewendet werden und die Produktausbeuten sind generell hoch. Eine effiziente Synthese von Clausin C im Gramm‐Maßstab demonstriert die Anwendbarkeit und Skalierbarkeit dieser neuen Methode.
Effect of flue gas components on Hg0 oxidation and adsorption by modified walnut shell coke in O2/CO2 atmosphere
Authors: Zhang Xiang , Duan Yufeng , Wang Hui , Ren Shaojun , Wei Hongqi 
Published: February 2020

AbstractWalnut shell was pyrolyzed and then impregnated with NH4Br to make sorbent for Hg0 removal. The effect of flue gas components on Hg0 removal performance was studied in O2/CO2 atmosphere, and the results were compared with those in O2/N2 atmosphere. The mercury valence distribution during adsorption was obtained. NH4Br‐modified walnut shell coke promoted Hg0 removal, the Br‐containing chemisorption site was a crucial factor. Although addition of CO2 did not introduce new oxygen‐containing functional groups or change the mercury species, Hg0 removal efficiency increased significantly. This may be because CO2 can increase the active sites on the carbon surface. In O2/N2 atmosphere, O2 promoted formation of active center on the sorbent surface, which made Hg0 more easily adsorbed and then reacted with Br‐functional group to form more HgBr2. In O2/CO2 atmosphere, O2 promoted formation of some reactive carbon–oxygen complexes which acted as catalyst to facilitate Hg0 oxidation and formation of HgO. NO improved removal of Hg0, because the C─O functional group on the sorbent surface could catalyze the conversion of NO to NO2 in the adsorbed state and then formed Hg2(NO3)2. SO2 consumed oxygen on the sorbent surface and inhibited the Hg0 removal.
Quantitative determination of rifampicin in aquatic products by stable isotope‐dilution high liquid chromatography–tandem mass spectrometry
Authors: Li Qin , Cao Jingyuan , Han Gang , Liu Huan , Yan Jie , Wu Lidong , Li Jincheng 
Published: February 2020

AbstractRifampicin is a semi‐synthetic broad‐spectrum antibiotic obtained from rifamycin B. It is one of the most effective first‐line antituberculosis drugs and is widely used in clinical practice. In the present study, we describe a rapid and sensitive method for the determination of rifampin in aquatic products by stable isotope‐dilution high liquid chromatography–tandem mass spectrometry (HPLC–MS/MS). Samples were extracted with the acetonitrile, degreased by hexane, and then concentrated by nitrogen blowing. After separation using a C18 column with a mixture of acetonitrile and water as mobile phase, it was determined by HPLC–MS/MS using the stable isotope‐dilution calibration method. The performance of our method was validated. The limit of detection was 0.25 μg kg−1 and the limit of quantification was 0.5 μg kg−1. At the three spiked levels of 0.5, 1.0 and 5.0 μg kg−1, the average recoveries of rifampicin in different aquatic products were between 75.28 and 107.6%, and the relative standard deviation ranged from 0.81 to 13.23%. This method was successfully applied for the determination of rifampin in different kinds of aquatic products and rifampicin residue was found in aquatic products obtained from markets in Beijing, China.
Recombinant Peptide Fusion Protein‐Templated Palladium Nanoparticles for Suzuki‐Miyaura and Stille Coupling Reactions
Authors: Mosleh Imann , Shahsavari Hamid R. , Beitle Robert , Beyzavi M. Hassan 
Published: February 2020

AbstractThis study examined the use of nanoparticles created with recombinant 45‐amino acid long peptides fused to green fluorescent protein (GFPuv) to catalyze twelve representative Suzuki‐Miyaura and Stille coupling reactions. A method was developed to prepare powders (Pd@GFP) containing protein and synthesized nanoparticles. Next, coupling reactions were performed in a green solvent without nanoparticle purification. Pd@GFP had high turnover frequencies for the synthesis of model compounds including lapatinib (Tykerb®) and could be recycled. This study establishes a potentially cost‐effective approach to prepare heterogeneous catalysts containing well‐defined nanoparticles enabling key C−C bond formation leading to synthetically and pharmaceutically interesting compounds.
Asymmetric Michael Reaction of Aldehydes and α‐Cyano α,β‐Unsaturated Esters Catalyzed by Diphenylprolinol Silyl Ether; a Facile Asymmetric Route to 3,4,5‐Trisubstituted Piperidines
Authors: Hayashi Yujiro , Odoh Amaechi Shedrack , Kranidiotis‐Hisatomi Nektarios 
Published: February 2020

AbstractA highly enantioselective diphenylprolinol silyl ether‐mediated asymmetric Michael reaction of a variety of aldehydes and β‐substituted α‐cyano α,β‐unsaturated esters was developed. The organocatalytic conjugate addition provided synthetically useful chiral adducts possessing three consecutive stereocenters and suitably oriented functional handles that were readily transformed via a sequence of reductive‐cyclization and subsequent epimerization to furnish single isomers of 3,4,5‐trisubstituted piperidines with high levels of yield and excellent enantiopurity.
Combining Cost‐Efficient Cellulose and Short‐Chain Carboxylic Acid Production: The Polyoxometalate (POM)‐Ionosolv Concept
Authors: Bukowski Anna , Esau Daniel , Rafat Said Aida Abouelela , Brandt‐Talbot Agnieszka , Albert Jakob 
Published: February 2020

AbstractFull cost‐effective exploitation of all wood components is key to growing a commercially successful biorefining industry. An innovative process is reported that combines fractionation of lignocellulosic biomass using a low‐cost ionic liquid (Ionosolv) and production of bio‐derived formic acid using polyoxometalates and molecular oxygen (OxFA process). We show that the hemicellulose and part of the lignin were selectively dissolved into the ionic liquid triethylammonium hydrogen sulfate and oxidised in situ to short‐chain, distillable carboxylic acids by a Keggin‐type polyoxometalate with high yields and selectivities. Characterization by several techniques, including ICP‐OES, FTIR, GC, HPLC and NMR spectroscopy confirmed stability of the catalyst over three consecutive POM‐Ionosolv recycles and stable formic acid yields.High formic acid yields of 26 % (pine chips), 23 % (beech chips), and 18 % (Miscanthus) were obtained with respect to the initial carbon content of the biomass, with unprecedented oxidation selectivities for formic acid of 54–62 % depending on vanadium substitution in the polyoxometalate, the processing temperature and the water content in the reaction mixture.. We also demonstrate that the cellulose rich pulp is a suitable source of glucose via enzymatic saccharification. We report cellulose yields of 37% for Miscanthus (from originally 48% glucan content), 33% for pine (from originally 49%) and 31% for beech (from originally 41%) were achieved, and a saccharification yield of up to 25% without optimisation. With further optimisation, this concept has the potential to generate two chemical products directly from lignocellulose in high yields and selectivities and hence a novel avenue for full utilisation of cellulose, hemicellulose and lignin.
Organic Cathode Materials for Rechargeable Zinc Batteries: Mechanisms, Challenges, and Perspectives
Authors: Cui Jin , Guo Zhaowei , Yi Jin , Liu Xiaoyu , Wu Kai , Liang Pengcheng , Li Qian , Liu Yuyu , Wang Yonggang , Xia Yongyao , Zhang Jiujun 
Published: February 2020

AbstractEnergy and environmental issues have given rise to the development of advanced energy‐storage devices worldwide. Electrochemical energy technologies, such as rechargeable batteries, are considered to be the most reliable and efficient candidates. Compared with other batteries, zinc‐based batteries seem promising due to their advantages, including inherent safety, cost‐effectiveness, and environmentally friendliness. As potential alternatives to conventional inorganic cathodes, organic cathodes for Zn–organic batteries have become a hot topic for research, owing to their favorable characteristics, such as easy structure design, controllable synthesis, and environmental benignancy. Herein, a systematic overview on the fundamentals of organic cathode materials for zinc batteries, including material design, electrochemical mechanisms, technical advances, and challenging analysis, is provided. Furthermore, perspectives and corresponding research directions are offered to facilitate the future development of organic cathode materials for zinc batteries toward practical applications.
Oxygen Reduction Reaction on Au Revisited at Different pH Values using in situ Surface‐Enhanced Raman Spectroscopy
Authors: Yu Hai‐Yang , Li Xiao‐Feng , Zhang Tian‐Heng , Liu Jiao , Tian Jing‐Hua , Yang Ruizhi 
Published: February 2020

AbstractThe mechanisms of the oxygen reduction reaction (ORR) on Au surfaces are revisited in electrolytes with different pH values by using a combination of electrochemical and in situ surface‐enhanced Raman scattering spectroscopy. Surprisingly, the in situ Raman signal of the O−O stretching vibration was detected during the ORR on a Au surface by using a λ=785 nm laser. Both the intermediate products O2− and H2O2 could be detected, which indicates the difficulty of the further reduction H2O2 and results in a lower electron transfer number, especially in neutral and acid electrolytes. The weak absorption ability of HO2 on the Au surface may explain the poor ORR in neutral and acid electrolytes. This work not only provides a deep insight to understand the reduction mechanisms of O2 on Au in electrolytes with different pH values but also supplies a new idea for the selection and optimization of electrolytes and efficient electrocatalysts for oxygen reduction.
Neprilysin inhibition, endorphin dynamics, and early symptomatic improvement in heart failure: a pilot study
Authors: Revuelta‐López Elena , Núñez Julio , Gastelurrutia Paloma , Cediel Germán , Januzzi James L. , Ibrahim Nasrien E. , Emdin Michele , VanKimmenade Roland , Pascual‐Figal Domingo , Núñez Eduardo , Gommans Frank , Lupón Josep , Bayés‐Genís Antoni 
Published: February 2020

AbstractAimSacubitril/valsartan is a first‐in‐class angiotensin receptor‐neprilysin inhibitor developed for the treatment of heart failure with reduced ejection fraction. Its benefits are achieved through the inhibition of neprilysin (NEP) and the specific blockade of the angiotensin receptor AT1. The many peptides metabolized by NEP suggest multifaceted potential consequences of its inhibition. We sought to evaluate the short‐term changes in serum endorphin (EP) values and their relation with patients' physical functioning after initiation of sacubitril/valsartan treatment.Methods and resultsA total of 105 patients with heart failure with reduced ejection fraction, who were candidates for sacubitril/valsartan treatment, were included in this prospective, observational, multicentre, and international study. In a first visit, and in agreement with current guidelines, treatment with angiotensin‐converting enzyme inhibitors or angiotensin receptor blocker was replaced by sacubitril/valsartan because of clinical indication by the responsible physician. By protocol, patients were reevaluated at 30 days after the start of sacubitril/valsartan. Serum levels of α‐ (α‐EP), γ‐Endorphin (γ‐EP), and soluble NEP (sNEP) were measured using enzyme‐linked immunoassays. New York Heart Association (NYHA) functional class was used as an indicator of patient's functional status. Baseline median levels of circulating α‐EP, γ‐EP, and sNEP were 582 (160–772), 101 (37–287), and 222 pg/mL (124–820), respectively. There was not a significant increase in α‐EP nor γ‐EP serum values after sacubitril/valsartan treatment (P value = 0.194 and 0.102, respectively). There were no significant differences in sNEP values between 30 days and baseline (P value = 0.103). Medians (IQR) of Δα‐EP, Δγ‐EP, and ΔsNEP between 30 days and baseline were 9.3 (−34 − 44), −3.0 (−46.0 − 18.9), and 0 units (−16.4 − 157.0), respectively. In a pre–post sacubitril/valsartan treatment comparison, there was a significant improvement in NYHA class, with 36 (34.3%) patients experiencing improvement by at least one NYHA class category. Δα‐EP and ΔsNEP showed to be significantly associated with NYHA class after 30 days of treatment (P = 0.014 and P < 0.001, respectively). Δα‐EP was linear and significantly associated with NYHA class improvement after 30 days of sacubitril/valsartan treatment.ConclusionsThese preliminary data suggest that beyond the haemodynamic benefits achieved with sacubitril/valsartan, the altered cleavage of endorphin peptides by NEP inhibition may participate in patients' symptoms improvement.
Early cardiac unloading with ImpellaCP™ in acute myocardial infarction with ventricular septal defect
Authors: Via Gabriele , Buson Stefania , Tavazzi Guido , Halasz Geza , Quagliana Angelo , Moccetti Marco , Demertzis Stefanos , Cassina Tiziano 
Published: February 2020

AbstractDespite a relative contraindication, mechanical support with Impella™ left ventricular assist device has already been described for ischaemic ventricular septal defect treatment, either as a bridge to surgery, as intraoperative mechanical haemodynamic support, or to ensure intraprocedural haemodynamic stability during device closure. We describe two cases of ventricular septal defect complicating acute myocardial infarction, where the percutaneous ImpellaCP was implanted early (differently than previously described) with the aim of preventing haemodynamic instability, while deferring surgical repair. We present a report of haemodynamic, echocardiographic, biochemical, and clinical data of two consecutive cases of ImpellaCP use, within a minimally invasive monitoring and therapeutic approach. In two cases of subacute myocardial infarction‐related ventricular septal defect not amenable to percutaneous device closure, the use ImpellaCP was successful: it was followed by effective and rapid right and left ventricular unloading, by major haemodynamic instability prevention and protection from systemic venous congestion, from kidney and splanchnic organ failures. This allowed bridging to appropriately timed surgical repair. These cases suggest a potentially effective, clinically grounded strategy in the early management of ischaemic ventricular septal defect patients, with the aim of deferring surgery beyond the safer 7 days cutoff associated with a lower perioperative mortality.
Policy knowledge among ‘elite citizens’
Authors: Jensen Carsten , Zohlnhöfer Reimut 
Published: February 2020

AbstractWe have a very limited understanding of citizens’ knowledge about their social rights. It is well‐established that people on average know little about politics and research also suggests that many harbor substantial misperceptions about the outcomes of benefit systems in terms of the amount of fraud, trends in claims, and overall costs. Yet, we lack solid insights into people's knowledge about the design of social rights (what we label ‘policy knowledge’ for short). It is precisely this knowledge on the design of social policies, however, which is of prime importance for scholars of social policy because this is what governments actually change when reforming the welfare state. Employing survey evidence from Denmark and Germany, we try to address this lacuna. We find a mixed picture in the sense that policy knowledge in a few specific issues is high, but typically, when the issue has been salient in the public. Overall, policy knowledge is low.
The use of environmental tracers to characterize a leaky CO2 CCS natural analogue site, Soda Springs, Idaho, USA
Authors: McLing Travis L. , Neupane Ghanashyam , Armstrong L. Trent , Smith Robert W. 
Published: February 2020

AbstractLarge‐scale global adoption of carbon capture and storage (CCS) as a means of minimizing atmospheric CO2 emissions requires an unprecedented effort to store gigatons of anthropogenic emissions in the earth's subsurface. Critical to the adoption and ultimate success of CCS is the protection of valuable water resources that may be impacted by leaking CO2 from CCS operations. Therefore, appropriate technical tools and societal controls will need to be developed and evaluated to maximize the atmospheric benefits of CCS while limiting potential deleterious effects of its implementation. Here, we utilize a naturally leaking CO2 system located at Soda Springs, Idaho, USA, as an analogue for industrial‐scale CCS deployment. This site is particularly relevant and useful for studying the consequences of CCS because it allows the examination of geologic systems at temporal and spatial scales not accessible by laboratory and field experiments.The Soda Springs system is an ideal CCS natural analogue site with the source of CO2 occurring at depths and temperatures expected for large‐scale CCS systems. Soda Springs also provides long‐term examples of at least three potential failure modes for CCS systems, including direct migration of CO2 charged brine to the surface via faulting or wells, upward movement of CO2 from the injection‐horizon into over lying shallow aquifers, and the displacement of reservoir brine into shallower aquifers. These failure mechanisms were differentiated and characterized utilizing variations in water chemistry including rare earth elements providing a framework for delineating the movement of CO2‐influenced fluids migrating from deep CCS reservoirs into overlying aquifers. © 2020 Society of Chemical Industry and John Wiley & Sons, Ltd.
Validation of the AMBIANCE‐brief: An observational screening instrument for disrupted caregiving
Authors: Cooke Jessica E. , Eirich Rachel , Racine Nicole , Lyons‐Ruth Karlen , Madigan Sheri 
Published: February 2020

ABSTRACTResulting from a community‐identified need for a well‐validated indicator of caregiving difficulties for use in practice settings, a brief form of the Atypical Maternal Behavior Instrument for Assessment and Classification System (AMBIANCE) was developed for use as a screening instrument. Prior to its dissemination, this study aimed to assess the feasibility, reliability, and validity of the AMBIANCE‐Brief. Adolescent mother–infant dyads (N = 69) participated in the Strange Situation Procedure, as well as play sessions with and without toys. Maternal disrupted caregiving was coded from the play sessions using the AMBIANCE and AMBIANCE‐Brief. The AMBIANCE‐Brief demonstrated convergent validity with the AMBIANCE in the play session with toys (r = .65, p < .001) and without toys (r = .61, p < .001). Concurrent validity of the AMBIANCE‐Brief was also demonstrated in relation to infant attachment disorganization in the play session with toys (r = .36, p < .05) and without toys (r = .32, p < .01). These findings suggest a shorter protocol for assessing disrupted caregiving may be feasible and valid for use in community settings. Future studies are in progress to train community practitioners in the use of the AMBIANCE‐Brief and to evaluate their reliability.
Prediction regions for interval‐valued time series
Authors: Gonzalez‐Rivera Gloria , Luo Yun , Ruiz Esther 
Published: February 2020

SummaryWe approximate probabilistic forecasts for interval‐valued time series by offering alternative approaches. After fitting a possibly non‐Gaussian bivariate vector autoregression (VAR) model to the center/log‐range system, we transform prediction regions (analytical and bootstrap) for this system into regions for center/range and upper/lower bounds systems. Monte Carlo simulations show that bootstrap methods are preferred according to several new metrics. For daily S&P 500 low/high returns, we build joint conditional prediction regions of the return level and volatility. We illustrate the usefulness of obtaining bootstrap forecasts regions for low/high returns by developing a trading strategy and showing its profitability when compared to using point forecasts.
Order‐invariant tests for proper calibration of multivariate density forecasts
Authors: Dovern Jonas , Manner Hans 
Published: February 2020

SummaryEstablished tests for proper calibration of multivariate density forecasts based on Rosenblatt probability integral transforms can be manipulated by changing the order of variables in the forecasting model. We derive order‐invariant tests. The new tests are applicable to densities of arbitrary dimensions and can deal with parameter estimation uncertainty and dynamic misspecification. Monte Carlo simulations show that they often have superior power relative to established approaches. We use the tests to evaluate generalized autoregressive conditional heteroskedasticity‐based multivariate density forecasts for a vector of stock market returns and macroeconomic forecasts from a Bayesian vector autoregression with time‐varying parameters.
Deleterious cardiovascular effect of exosome in digitalis‐treated decompensated congestive heart failure
Authors: Fu Jin‐Ling , Yu Qiong , Li Meng‐Di , Hu Chun‐Mei , Shi Guang 
Published: February 2020

AbstractHeart failure (HF) is a medical condition inability of the heart to pump sufficient blood to meet the metabolic demand of the body to take place. The number of hospitalized patients with cardiovascular diseases is estimated to be more than 1 million each year, of which 80% to 90% of patients ultimately progress to decompensated HF. Digitalis glycosides exert modest inotropic actions when administered to patients with decompensated HF. Although its efficacy in patients with HF and atrial fibrillation is clear, its value in patients with HF and sinus rhythm has often been questioned. A series of recent studies have cast serious doubt on the benefit of digoxin when added to contemporary HF treatment. We are hypothesizing the role and mechanism of exosome and its biological constituents responsible for worsening the disease state and mortality in decompensated HF patients on digitalis.
Tranilast attenuates methotrexate‐induced renal and hepatic toxicities: Role of apoptosis‐induced tissue proliferation
Authors: Helal Manar Gamal , Said Eman 
Published: February 2020

AbstractDrug‐induced organ toxicity is a frequently encountered obstacle in the field of medical practice that limits the use of numerous pharmacologically valuable drugs. Methotrexate (MTX)‐induced organ toxicity is unfortunately the rate‐limiting factor for its clinical application. In the current study, MTX injection induced significant renal and hepatic toxicities manifested on functional, biochemical, and histopathological scales. This was associated with a significant elevation in both renal and hepatic contents of TNF‐related apoptosis–inducing ligand (TRAIL) and caspase‐8, biomarkers of tissue apoptosis. Inline, immunohistochemical analysis confirmed that tissue increased expression of Ki67 as a biomarker of tissue regeneration in both organs. Tranilast (TRAN) is a small molecular weight anti‐inflammatory and antiallergic agent. TRAN's coadministration with MTX in the current study induced a significant tissue recovery via modulation of TRAIL/caspase‐8 signaling and modulation of apoptosis‐induced tissue proliferation confirmed by quantification of Ki67 expression. In conclusion, TRAN can be proposed as an effective drug to attenuate MTX‐induced organ toxicity via modulation of apoptosis‐induced tissue proliferation pathway.