bluuebunny/crossref_metadata_2025_split huggingface dataset:
Study of a Stable “Trifluoromethoxide Anion Solution” Arising from 2,4‐Dinitro‐Trifluoromethoxybenzene
Authors: Bonnefoy Clémence , Chefdeville Emmanuel , Panosian Armen , Hanquet Gilles , Leroux Frédéric R. , Toulgoat Fabien , Billard Thierry 
Published: September 2021

AbstractDespite recent advances, trifluoromethoxylation remains a challenging reaction. Here we describe an efficient trifluoromethoxylative substitution, using an inexpensive and easy‐to‐handle reagent. By mixing DMAP with a slight excess of 1,4‐dinitro‐trifluoromethoxybenzene (DNTFB), a stable solution of trifluoromethoxide anion is obtained and can be used to perform a SN2 reaction without any silver additives. A precise study of the properties and behavior of this unusual stable solution of CF3O−species is also performed.
The Role of Common Alcoholic Sacrificial Agents in Photocatalysis: Is It Always Trivial?
Authors: Sathiyan Krishnamoorthy , Bar‐Ziv Ronen , Marks Vered , Meyerstein Dan , Zidki Tomer 
Published: September 2021

AbstractPhotocatalytic hydrogen production is proposed as a sustainable energy source. Simultaneous reduction and oxidation of water is a complex multistep reaction with high overpotential. Photocatalytic processes involving semiconductors transfer electrons from the valence band to the conduction band. Sacrificial substrates that react with the photochemically formed holes in the valence band are often used to study the mechanism of H2 production, as they scavenge the holes and hinder charge carrier recombination (electron‐hole pairs). Here, we show that the desired sacrificial agent is one forming a radical that is a fairly strong reducing agent, and whose oxidized form is not a good electron acceptor that might suppress the hydrogen evolution reaction (HER). In an acidic medium, methanol was found to fulfill both these requirements better than ethanol and propan‐2‐ol in the TiO2‐(M0‐NPs) (M=Au or Pt) system, whereas in an alkaline medium, the alcohols exhibit a reverse order of activity. Moreover, we report that CH2(OH)2 is by far the most efficient sacrificial agent in a nontrivial mechanism in acidic media. Our study provides general guidelines for choosing an appropriate sacrificial substrate and helps to explain the variance in the performance of alcohol scavenger‐based photocatalytic systems.
Expanding the Chemical Space of Tetracyanobuta‐1,3‐diene (TCBD) through a Cyano‐Diels‐Alder Reaction: Synthesis, Structure, and Physicochemical Properties of an Anthryl‐fused‐TCBD Derivative
Authors: Mateo Luis M. , Sagresti Luca , Luo Yusen , Guldi Dirk M. , Torres Tomas , Brancato Giuseppe , Bottari Giovanni 
Published: September 2021

AbstractTetracyanobuta‐1,3‐diene (TCBD) is a powerful and versatile electron‐acceptor moiety widely used for the preparation of electroactive conjugates. While many reports addressing its electron‐accepting capability have appeared in the literature, significantly scarcer are those dealing with its chemical modification, a relevant topic which allows to broaden the chemical space of this interesting functional unit. Here, we report on the first example of a high‐yielding cyano‐Diels‐Alder (CDA) reaction between TCBD, that is, where a nitrile group acts as a dienophile, and an anthryl moiety, that is, acting as a diene. The resulting anthryl‐fused‐TCBD derivative, which structure was unambiguously identified by X‐ray diffraction, shows high thermal stability, remarkable electron‐accepting capability, and interesting electronic ground‐ and excited‐state features, as characterized by a thorough theoretical, electrochemical, and photophysical investigation. Moreover, a detailed kinetic analysis of the intramolecular CDA reaction transforming the anthryl‐TCBD‐based reactant into the anthryl‐fused‐TCBD product was carried out at different temperatures.
Lewis Superacidic Tellurenyl Cation‐Induced Electrophilic Activation of an Inert Carborane
Authors: Hejda Martin , Duvinage Daniel , Lork Enno , Lyčka Antonín , Černošek Zdeněk , Macháček Jan , Makarov Sergey , Ketkov Sergey , Mebs Stefan , Dostál Libor , Beckmann Jens 
Published: September 2021

AbstractThe aryltellurenyl cation [2‐(tBuNCH)C6H4Te]+, a Lewis super acid, and the weakly coordinating carborane anion [CB11H12]−, an extremely weak Brønsted acid (pKa=131.0 in MeCN), form an isolable ion pair complex [2‐(tBuNCH)C6H4Te][CB11H12], in which the Brønsted acidity (pKa 7.4 in MeCN) of the formally hydridic B−H bonds is dramatically increased by more than 120 orders of magnitude. The electrophilic activation of B−H bonds in the carborane moiety gives rise to a proton transfer from boron to nitrogen at slightly elevated temperatures, as rationalized by the isolation of a mixture of the zwitterionic isomers 12‐ and 7‐[2‐(tBuN{H}CH)C6H4Te(CB11H11)] in ratios ranging from 62 : 38 to 80 : 20.
Synergistic Peptide and Gold Catalysis: Enantioselective Addition of Branched Aldehydes to Allenamides
Authors: Nicholls Leo D. M. , Wennemers Helma 
Published: September 2021

AbstractThe combination of a peptide catalyst and a gold catalyst is presented for enantioselective addition reactions between branched aldehydes and allenamides. The two catalysts act in concert to provide γ,δ‐enamide aldehydes bearing a fully substituted, benzylic stereogenic center – a structural motif common in many natural products and therapeutically active compounds – with good yields and enantioselectivities. The reaction tolerates a variety of alkyl and alkoxy substituted aldehydes and the products can be elaborated into several chiral building blocks bearing either 1,4‐ or 1,5‐ functional group relationships. Mechanistic studies showed that the conformational features of the peptide are important for both the catalytic efficiency and stereochemistry, while a balance of acid/base additives is key for ensuring formation of the desired product over undesired side reactions.
The Effect of Pristine and Hydroxylated Oxide Surfaces on the Guaiacol HDO Process: A DFT Study
Authors: Morteo‐Flores Fabian , Roldan Alberto 
Published: September 2021

AbstractThe acid‐base character of oxide supports is crucial for catalytic reactions. In this work, the acid‐base properties of five oxide surfaces common in heterogeneous catalysis were investigated and related to their interaction with monolignol compounds derived from lignin. We have used density functional theory simulations also to understand the role of the surfaces’ hydroxylation state. The results show that moderate hydroxyl coverage on the amphoteric γ‐Al2O3 (110) slightly strengthens the oxy‐compounds’ adsorption due to an increase in Lewis acidity. Similarly, low hydroxyl coverage on the reducible TiO2 (101) enlarges its adsorption capacity by up to 42 % compared with its clean surface. The higher affinity is attributed to the more favourable interaction between the surface‐OH groups and the aromatic rings. Overall, the results indicate that hydroxyl coverage enhances the amphoteric and reducible adsorption capacity towards aromatic species.
Circular Polarization of Luminescence as a Tool To Study Molecular Dynamical Processes
Authors: Meskers Stefan C. J. 
Published: September 2021

AbstractCircular polarization of luminescence is a phenomenon that can be observed for chiral molecules in isotropic solution, for molecular aggregates and molecular materials. Also, the electroluminescence from chiral molecular materials in organic light emitting diodes can be nearly completely circularly polarized. In this review we focus on the latest developments in experimental results for the categories listed above. A unifying description of the origin of the circular polarization is still missing. We revisit the very earliest efforts to measure and understand circular polarization in light emission in order to better understand the present day confusion on the origins of the polarization. It seems that quantum field theory of electromagnetic interactions could provide leads for a comprehensive description of the circular polarization including contributions from helicity at all possible length scales from the molecular to the macroscopic.
Sequential Indirect Dual Immunohistochemistry with Primary Rabbit Antibodies on Cochlear Sections Using an Intermediate Heat‐Denaturation Step
Authors: Luque Maria , Glueckert Rudolf 
Published: September 2021

AbstractAdvanced immunohistochemical (IHC) protocols aim to visualize different molecules in situ simultaneously. These techniques are of utmost importance as a first step in studying possible interactions of proteins at the subcellular level. Colocalized stains in tissue sections indicate proximity of two proteins of interest. Frequently, double staining protocols are restricted by the lack of primary antibodies generated in different animal species for indirect IHC visualization. Here, we present a detailed protocol for mouse inner ear tissue using two different primary rabbit antibodies directed against transmembrane ion channel proteins of cochlear neurons. The two antibodies are combined for fluorescence (confocal) as well as dual multiplex colorimetric visualization in two sequential single IHC stainings. A heat‐denaturation step is performed in between. Primary antibody specificity is tested by preadsorption with the immunogenic peptide, and positive and negative tissue controls are performed to confirm the reliability of the antibody detection. We describe the whole procedure in detail beginning with tissue extraction of the mouse inner ear and continuing with chemical fixation, cryoembedding, and preparation for manual and fully automated immunostaining, including steps for heat‐induced antigen retrieval. The potential to use antibodies from the same host species for single and double IHC staining opens up multiple possibilities for detecting different targets in the same tissue section using resources and materials that are widely available. © 2021 The Authors. Current Protocols published by Wiley Periodicals LLC.Basic Protocol 1: Tissue preparation, cryoembedding, and sectioningBasic Protocol 2: Double colorimetric immunostaining with an automatic immunostainerBasic Protocol 3: Double manual fluorometric immunostaining with fluorescence
Linking environmentally‐specific transformational leadership and employees' green advocacy: The influence of leadership integrity
Authors: Crucke Saskia , Servaes Marie , Kluijtmans Tom , Mertens Shana , Schollaert Eveline 
Published: September 2021

AbstractGiven the environmental challenges facing organizations, there is an increasing interest in how to stimulate the green behavior of employees. This study focuses on how leaders foster green advocacy, a specific category of green behavior that refers to influencing others to demonstrate green behavior by sharing environmental knowledge and discussing environmental issues. Our study, using a sample of 363 employees of a Belgian grocery retail company, provides valuable insights on the complex role of leaders in stimulating green advocacy. The results reveal that environmentally‐specific transformational leadership is positively related to employees' green advocacy. Our results further provide insights into the underlying mechanisms explaining this relationship, as we find that environmentally‐specific transformational leadership is indirectly related to employees' green advocacy through environmental CSR and organizational environmental support. Finally, leadership integrity is found to positively moderate the direct as well as the indirect relationship between environmentally‐specific transformational leadership and green advocacy.
Detection of REST expression in the testis using epitope‐tag knock‐in mice generated by genome editing
Authors: Kimura Ryuichi , U. Inoue Yukiko , Kikkawa Takako , Tatehana Misako , Morimoto Yuki , Inada Hitoshi , Oki Shinya , Inoue Takayoshi , Osumi Noriko 
Published: September 2021

AbstractBackgroundRepressor element 1‐silencing transcription factor (REST) is a master regulator that is highly expressed in multipotent stem cells to repress gene networks involving a wide range of biological processes. A recent study has suggested that REST might be involved in a misregulation of its target genes in the embryonic brain of offspring derived from aged fathers. However, detailed analyses of the REST function in spermatogenesis are lacking due to difficulty in the detection of REST protein in specific cell types.ResultsTo determine localization of REST, we generated an epitope tag knock‐in (KI) mouse line with the C‐terminus insertion of a podoplanin (PA)‐tag at an endogenous Rest locus by the CRISPR/Cas9 system. Localization of the PA‐tag was confirmed in neural stem cells marked with Pax6 in the embryonic brain. Moreover, PA‐tagged REST was detected in undifferentiated and differentiating spermatogonia as well as Sertoli cells in both neonatal and adult testes.ConclusionsWe demonstrate that REST is expressed at the early step of spermatogenesis and suggest a possibility that REST may modulate the epigenetic state of male germline cells. Our KI mice may be useful for studying REST‐associated molecular mechanisms of neurodevelopmental and age‐related disorders.
Decline of unique Pontocaspian biodiversity in the Black Sea Basin: A review
Authors: Gogaladze Aleksandre , Son Mikhail O. , Lattuada Matteo , Anistratenko Vitaliy V. , Syomin Vitaly L. , Pavel Ana Bianca , Popa Oana P. , Popa Luis O. , ter Poorten Jan‐Johan , Biesmeijer Jacobus C. , Raes Niels , Wilke Thomas , Sands Arthur F. , Trichkova Teodora , Hubenov Zdravko K. , Vinarski Maxim V. , Anistratenko Olga Yu , Alexenko Tatiana L. , Wesselingh Frank P. 
Published: September 2021

AbstractThe unique aquatic Pontocaspian (PC) biota of the Black Sea Basin (BSB) is in decline. The lack of detailed knowledge on the status and trends of species, populations, and communities hampers a thorough risk assessment and precludes effective conservation. This paper reviews PC biodiversity trends in the BSB (Bulgaria, Romania, Moldova, Ukraine, and Russia) using endemic mollusks as a model group. We aim to assess changes in PC habitats, community structure, and species distribution over the past century and to identify direct anthropogenic threats. The presence/absence data of target mollusk species were assembled from literature, reports, and personal observations. Pontocaspian biodiversity trends in the northwestern BSB coastal regions were established by comparing 20th‐ and 21st‐century occurrences. The direct drivers of habitat and biodiversity change were identified and documented. We found that a pronounced decline of PC species and communities is driven by (a) damming of rivers, (b) habitat modifications that disturbed previous natural salinity gradients and settings in the studied area, (c) pollution and eutrophication, (d) invasive alien species, and (e) climate change. Four out of the 10 studied regions, namely, the Danube Delta–Razim Lake system, Dniester Liman, Dnieper–Bug estuary, and Taganrog Bay–Don Delta, contain favorable ecological conditions for PC communities and still host threatened endemic PC mollusk species. Distribution data are incomplete, but the scale of deterioration of PC species and communities is evident from the assembled data, as are major direct threats. Pontocaspian biodiversity in the BSB is profoundly affected by human activities. Standardized observation and collection data as well as precise definition of PC biota and habitats are necessary for targeted conservation actions. This study will help to set the research and policy agenda required to improve data collection to accommodate effective conservation of the unique PC biota.
Cost‐utility analysis of add‐on dapagliflozin in heart failure with reduced ejection fraction in the Philippines
Authors: Mendoza Victor L. , Tumanan‐Mendoza Bernadette A. , Punzalan Felix Eduardo R. 
Published: September 2021

AbstractAimWe aim to determine the cost‐effectiveness of dapagliflozin in addition to standard therapy versus standard therapy alone among patients with heart failure with reduced ejection fraction (HFrEF) using the public healthcare provider's perspective in the Philippines.Methods and resultsA thousand Filipino patients with HFrEF (with or without type 2 diabetes mellitus) were included in a simulation cohort using a lifetime Markov model. The model, which was developed based on the results of the Dapagliflozin and Prevention of Adverse Outcomes in Heart Failure trial, was composed of three health states. These were ‘alive without an event’ (chronic heart failure state), ‘alive but was hospitalized for heart failure’ (worsening heart failure), and ‘dead’ (death from any cause). Data regarding costs and utilities were obtained from previous studies and local data. These were used to estimate the incremental cost per quality‐adjusted life‐year (ICER). A 3% annual discount rate was used for both costs and effects. One‐way (deterministic) and probabilistic sensitivity analyses as well as scenario analyses were performed. The ICER for the addition of dapagliflozin to standard therapy among HFrEF patients was PHP177 868 (US$3434) and PHP160 983 (US$3108), respectively, if the present price (PHP44.00) and possible negotiated unit cost of dapagliflozin 10 mg tablet (PHP40.00) were used. These were deemed cost‐effective because they were both below the threshold ICER which was equivalent to the gross domestic product per capita of the Philippines in 2019, PHP180 500 (US$3485). Using the unit costs of dapagliflozin previously mentioned, the ICERs among HFrEF patients with diabetes were PHP132 582 (US$2560) and PHP120 249 (US$2321), respectively. Doing PSA involving Monte Carlo simulation of 10 000 iterations and plotting the resulting ICERs against the threshold ICER in the cost‐effectiveness acceptability curves, these ICERs for HFrEF among diabetics were determined to be 72% and 76% cost‐effective.ConclusionDapagliflozin added to standard therapy for HFrEF patients is likely to be cost‐effective using the perspective of the Philippine public healthcare provider.
Sympathetic vasoconstrictor activity before and after left ventricular assist device implantation in patients with end‐stage heart failure
Authors: Heusser Karsten , Wittkoepper Judith , Bara Christoph , Haverich Axel , Diedrich André , Levine Benjamin D. , Schmitto Jan D. , Jordan Jens , Tank Jens 
Published: September 2021

AbstractAimsSympathetic overactivity, which predicts poor outcome in patients with heart failure, normalizes following cardiac transplantation. We tested the hypothesis that haemodynamic improvement following left ventricular assist device (LVAD) implantation is also associated with reductions in centrally generated sympathetic activity.Methods and resultsIn eight patients with heart failure (two women, six men, age 44–66 years), we continuously recorded electrocardiogram, beat‐to‐beat finger blood pressure, respiration, and muscle sympathetic nerve activity (MSNA) before and after implantation of the continuous‐flow LVAD devices HeartWare HVAD (n = 4) and HeartMate II (n = 2), and the non‐continuous‐flow device HeartMate 3 (n = 2). LVAD implantation increased cardiac output by 1.29 ± 0.88 L/min (P = 0.060) and mean arterial pressure by 16.2 ± 7.9 mmHg (P < 0.001), while reducing pulse pressure by 25.3 ± 9.8 mmHg (P < 0.001). LVAD implantation did not change MSNA burst frequency (−1.3 ± 7.5 bursts/min, P = 0.636), total activity (+0.62 ± 1.83 au, P = 0.369), or normalized activity (+0.63 ± 4.23, P = 0.685). MSNA burst incidence was decreased (−7.8 ± 9.3 bursts/100 heart beats, P = 0.049). However, cardiac ectopy altered MSNA bursting patterns that could be mistaken for sympatholysis.ConclusionImplantation of current design LVAD does not consistently normalize sympathetic activity in patients with end‐stage heart failure despite haemodynamic improvement.
Ammonium Chloride‐Promoted Rapid Synthesis of Monosubstituted Ureas under Microwave Irradiation
Authors: Lan Chunling Blue , Auclair Karine 
Published: September 2021

AbstractMonosubstituted ureas are important scaffolds in organic chemistry. They appear in various biologically active compounds and serve as versatile precursors in synthesis. Monosubstituted ureas were originally prepared using toxic and hazardous phosgene equivalents. Modern methods include transamidation of urea and nucleophilic addition to cyanate salts, both of which suffer from a narrow substrate scope due to the need for a strong acid and prolonged reaction times. We hereby report that ammonium chloride can promote the reaction between amines and potassium cyanate to generate monosubstituted ureas in water. This method proceeds rapidly under microwave irradiation and tolerates a broad range of functional groups. Unlike previous strategies, it is compatible with other nucleophiles, acid‐labile moieties, and most of the common protecting groups. The products precipitate out of solution, allowing facile isolation without column chromatography.
A review and analysis of secure and lightweight ECC‐based RFID authentication protocol for Internet of Vehicles
Authors: Kumar Sanjeev , Banka Haider , Kaushik Baijnath , Sharma Surbhi 
Published: September 2021

AbstractRadio‐frequency identification (RFID) technology has proliferated over the last few years and being deployed as identification technology in numerous domains like intelligent transportation systems (ITS) and Internet of Vehicles (IoV) for applications like road safety, efficient traffic management, automatic toll collection, intelligent parking, etc. As RFID devices, as well as the possible domains of ITS and IoV onto which the RFID technology can be deployed, are usually resource‐constrained, thus, security and privacy become a major concern. So, public‐key cryptography becomes the better choice for enhancing the security of RFID based systems. Elliptic curve cryptography (ECC) is one of the dominant and secure asymmetric‐key cryptosystems being used for RFID security due to its smaller key size. Numerous RFID authentication schemes based on ECC have been suggested in literature, however, the majority has various serious security weaknesses. To bridge those existing security weaknesses, an enhanced ECC based light weight protocol for RFID systems has been proposed in this article. An extensive security analysis has been performed to demonstrate various secure features offered by our proposed protocol, and formal security analysis is being conducted using Automated Validation of Internet Security Protocols and Applications tool. The performance of our proposed RFID protocol has been compared with various existing RFID based security solutions on the basis of parameters, that is, computational cost, communication cost, and storage requirement. Simulation results indicate that the proposed lightweight protocol is more secure and performance efficient than the existing RFID protocols, and is well suited for practical applications.
Payment schemes and treatment responses after a demand shock in mental health care
Authors: Douven Rudy , Remmerswaal Minke , Vervliet Tobias 
Published: September 2021

AbstractWe study whether two groups of mental health care providers—each paid according to a different payment scheme—adjusted the duration of their patients' treatments after they faced an exogenous 20% drop in the number of patients. For the first group of providers, self‐employed providers, we find that they did not increase treatment duration to recoup their income loss. Treatment duration thresholds in the stepwise fee‐for‐service payment function seem to have prevented these providers to treat patients longer. For the second group of providers, large mental health care institutions who were subject to a budget constraint, we find an average increase in treatment duration of 8%. Prior rationing combined with professional uncertainty can explain this increase. We find suggestive evidence for overtreatment of patients as the longer treatments did not result in better patient outcomes, i.e. better General Assessment of Functioning scores.