bluuebunny/crossref_metadata_2025_split huggingface dataset:
Indoloquinoline Ligands Favor Intercalation at Quadruplex‐Duplex Interfaces
Authors: Vianney Yoanes Maria , Weisz Klaus 
Published: December 2021

AbstractQuadruplex‐duplex (Q‐D) junctions are increasingly considered promising targets for medicinal and technological applications. Here, a Q‐D hybrid with a hairpin‐type snapback loop coaxially stacked onto the quadruplex 3’‐outer tetrad was designed and employed as a target structure for the indoloquinoline ligand SYUIQ‐5. NMR spectral analysis demonstrated high‐affinity binding of the ligand at the quadruplex‐duplex interface with association constants determined by isothermal titration calorimetry of about 107 M−1 and large exothermicities ΔH° of −14 kcal/mol in a 120 mM K+ buffer at 40 °C. Determination of the ligand‐bound hybrid structure revealed intercalation of SYUIQ‐5 between 3’‐outer tetrad and the neighboring CG base pair, maximizing π–π stacking as well as electrostatic interactions with guanine carbonyl groups in close vicinity to the positively charged protonated quinoline nitrogen of the tetracyclic indoloquinoline. Exhibiting considerable flexibility, the SYUIQ‐5 sidechain resides in the duplex minor groove. Based on comparative binding studies with the non‐substituted N5‐methylated indoloquinoline cryptolepine, the sidechain is suggested to confer additional affinity and to fix the alignment of the intercalated indoloquinoline aromatic core. However, selectivity for the Q‐D junction mostly relies on the geometry and charge distribution of the indoloquinoline ring system. The presented results are expected to provide valuable guidelines for the design of ligands specifically targeting Q‐D interfaces.
Resolution of (R,S)‐1‐(4‐methoxyphenyl)ethanol by lipase‐catalyzed stereoselective transesterification and the process optimization
Authors: He Bingbing , Tang Fengci , Sun Chenrui , Su Jiahao , Wu Bingcheng , Chen Yan , Xiao Yuquan , Zhang Panliang , Tang Kewen 
Published: December 2021

AbstractAn efficient lipase‐catalyzed stereoselective transesterification reaction system was established for resolution of 1‐(4‐methoxyphenyl)ethanol (MOPE) enantiomers. A series of lipases were tested and compared. The immobilized lipase Novozym 40086 is selected as the best choice. The effects of organic solvent, acyl donor, time and temperature on substrate conversion (c), and optical purity of the remaining substrate (eeS) were investigated. Response surface methodology and central composite design were employed to evaluate the effect of some important factors and to optimize the process. Under the optimized conditions including solvent of n‐hexane, acyl donor of vinyl acetate, temperature of 35°C, substrate molar ratio of 1:6, enzyme dosage of 20 mg, and reaction time of 2.5 h, eeS of 99.87% with c of 56.71% is achieved. The use of alkane solvent and immobilized enzyme, the mild reaction conditions, and the reduced reaction time make the system promising in industrial application.
A Naked‐eye Colorimetric pH and Temperature Sensor Based on Gold Nanoparticle‐Loaded Stimuli‐Sensitive Dendrimers
Authors: Kojima Chie , Xia Hai , Yamamoto Yojiro , Shiigi Hiroshi 
Published: December 2021

AbstractGold nanoparticles (AuNPs) show unique size‐ and shape‐dependent photosensitive properties resulting from localized surface plasmon resonance, which can be exploited in colorimetric sensors. Polyamidoamine (PAMAM) dendrimers are suitable nanotemplates of AuNPs and nanoplatforms of some stimuli‐responsive materials. In this study, AuNP was loaded in phenylalanine (Phe)‐modified PAMAM dendrimers with dual pH‐ and temperature‐sensitive properties to produce a naked‐eye colorimetric sensor with responsivity to both pH and temperature. The ultraviolet‐visible (UV‐Vis) spectra of AuNP‐loaded PAMAM‐Phe‐Suc were changed by heating at pH 4 and 5, but unchanged at pH above 5.5. The UV‐Vis spectra of AuNP‐loaded PAMAM‐Phe and PAMAM‐Suc were only slightly changed by heating at pH above 5.5 and at pH 4 and 5, respectively. In solution, AuNP‐loaded PAMAM‐Phe‐Suc changed color (from brown to gray) under high temperature (≥50 °C) and acidic (pH≤5) conditions, suggesting its functionality as a naked‐eye colorimetric dual pH and temperature sensor.
Assessing the impact of minor modifications on the interior structure of GRU: GRU1 and GRU2
Authors: Yigit Gulsum , Amasyali Mehmet Fatih 
Published: December 2021

AbstractIn this study, two GRU variants named GRU1 and GRU2 are proposed by employing simple changes to the internal structure of the standard GRU, which is one of the popular RNN variants. Comparative experiments are conducted on four problems: language modeling, question answering, addition task, and sentiment analysis. Moreover, in the addition task, curriculum learning and anti‐curriculum learning strategies, which extend the training data having examples from easy to hard or from hard to easy, are comparatively evaluated. Accordingly, the GRU1 and GRU2 variants outperformed the standard GRU. In addition, the curriculum learning approach, in which the training data is expanded from easy to difficult, improves the performance considerably.
Alkylimidazolium Protic Ionic Liquids: Structural Features and Physicochemical Properties
Authors: Shmukler Liudmila E. , Fedorova Irina V. , Fadeeva Yuliya A. , Gruzdev Matvey S. , Safonova Liubov P. 
Published: December 2021

AbstractWe focus on a series of protic ionic liquids (PILs) with imidazolium and alkylimidazolium (1R3HIm, R=methyl, ethyl, propyl, and butyl) cations. Using the literature data and our experimental results on the thermal and transport properties, we analyze the effects of the anion nature and the alkyl radical length in the cation structure on the above properties. DFT calculations in gas and solvent phase provide further microscopic insights into the structure and cation‐anion binding in these PILs. We show that the higher thermodynamic stability of an ion pair raises the PIL decomposition temperature. The melting points of the salts with the same cation decrease as the hydrocarbon radical in the cation becomes longer, which correlates with the weaker ion‐ion interaction inthe ion pairs. A comparative analysis of the protic ILs and corresponding ILs (1R3MeIm) with the same radical (R) in the cation structure and the same anion has been performed. The lower melting points of the ILs with 1R3MeIm cations are assumed to result from the weakening of both the ion‐ion interaction and the hydrogen bond.
Maladaptive emotion regulation strategies and trait anger as predictors of depression severity
Authors: Crisan Stefania Maria , Nechita Diana Mirela 
Published: December 2021

AbstractBackgroundAccording to empirical evidence, trait anger and emotion regulation strategies are associated with depression severity. The objective of this study was to investigate the impact of trait anger and maladaptive emotion regulation strategies in explaining the variance of depressive symptoms severity.MethodsTwo hundred three participants diagnosed with major depressive disorder completed measures of depression, trait anger, depressive rumination, anger rumination and experiential avoidance. Path analysis using Mplus was employed for data analysis.ResultsTrait anger and depressive rumination were significant predictors of the level of depressive symptomatology, while experiential avoidance and anger rumination did not predict the level of depressive symptoms severity.ConclusionMaladaptive emotion regulation strategies and trait anger seem to be associated with the level of depressive symptoms, and, as such, should also be investigated when working with depressive symptomatology.
Mechanistic Modeling of Primaquine Pharmacokinetics, Gametocytocidal Activity, and Mosquito Infectivity
Authors: Chotsiri Palang , Mahamar Almahamoudou , Hoglund Richard M. , Koita Fanta , Sanogo Koualy , Diawara Halimatou , Dicko Alassane , Simpson Julie A. , Bousema Teun , White Nicholas J. , Brown Joelle M. , Gosling Roly , Chen Ingrid , Tarning Joel 
Published: December 2021

Clinical studies have shown that adding a single 0.25 mg base/kg dose of primaquine to standard antimalarial regimens rapidly sterilizes Plasmodium falciparum gametocytes. However, the mechanism of action and overall impact on malaria transmission is still unknown. Using data from 81 adult Malians with P. falciparum gametocytemia who received the standard dihydroartemisinin‐piperaquine treatment course and were randomized to receive either a single dose of primaquine between 0.0625 and 0.5 mg base/kg or placebo, we characterized the pharmacokinetic‐pharmacodynamic relationships for transmission blocking activity. Both gametocyte clearance and mosquito infectivity were assessed. A mechanistically linked pharmacokinetic‐pharmacodynamic model adequately described primaquine and carboxy‐primaquine pharmacokinetics, gametocyte dynamics, and mosquito infectivity at different clinical doses of primaquine. Primaquine showed a dose‐dependent gametocytocidal effect that precedes clearance. A single low dose of primaquine (0.25 mg/kg) rapidly prevented P. falciparum transmissibility.
Systematic Influence of Electronic Modification of Ligands on the Catalytic Rate of Water Oxidation by a Single‐Site Ru‐Based Catalyst
Authors: Patel Jully , Bury Gabriel , Ravari Alireza K. , Ezhov Roman , Pushkar Yulia 
Published: December 2021

AbstractCatalytic water oxidation is an important process for the development of clean energy solutions and energy storage. Despite the significant number of reports on active catalysts, systematic control of the catalytic activity remains elusive. In this study, descriptors are explored that can be correlated with catalytic activity. [Ru(tpy)(pic)2(H2O)](NO3)2 and [Ru(EtO‐tpy)(pic)2(H2O)](NO3)2 (where tpy=2,2′ : 6′,2“‐terpyridine, EtO‐tpy=4′‐(ethoxy)‐2,2′:6′,2”‐terpyridine, pic=4‐picoline) are synthesized and characterized by NMR, UV/Vis, EPR, resonance Raman, and X‐ray absorption spectroscopy, and electrochemical analysis. Addition of the ethoxy group increases the catalytic activity in chemically driven and photocatalytic water oxidation. Thus, the effect of the electron‐donating group known for the [Ru(tpy)(bpy)(H2O)]2+ family is transferable to architectures with a tpy ligand trans to the Ru‐oxo unit. Under catalytic conditions, [Ru(EtO‐tpy)(pic)2(H2O)](NO3)2 displays new spectroscopic signals tentatively assigned to a peroxo intermediate. Reaction pathways were analyzed by using DFT calculations. [Ru(EtO‐tpy)(pic)2(H2O)](NO3)2 is found to be one of the most active catalysts functioning by a water nucleophilic attack mechanism.
Single‐Step Sustainable Production of Hydroxy‐Functionalized 2‐Imidazolines from Carbohydrates
Authors: Yu Feng , Darcel Christophe , Fischmeister Cédric 
Published: December 2021

AbstractManufacturing valuable N‐containing chemicals from biomass is highly desirable yet challenging. Herein, a novel strategy was developed for efficient production of 2‐(1‐hydroxyethyl)‐imidazoline (HI), a high‐value and versatile building block for synthesizing a myriad of bioactive targets, directly from carbohydrates under mild reaction conditions. With this strategy, bio‐based HI was produced from fructose in one step with as high as 77 C % isolated yield in the presence of ethylenediamine (EDA) and InCl3 at 130 °C. The synergistic functions of EDA and InCl3 were identified for the transformation, wherein EDA promoted the scission of C−C bond of fructose backbone via retro‐aldol (R−A) reaction and rapidly trapped in‐situ formed reactive carbonyl‐containing C3 intermediate for HI formation to avoid undesired side reaction, and InCl3 facilitated the formation of this C3 intermediate and the final 1,2‐hydrid shift step.
Performance analysis of NOMA uplink transmission over generalized‐K fading channels
Authors: Aslan Kardes , Gucluoglu Tansal 
Published: December 2021

SummaryNon‐orthogonal multiple access (NOMA) can serve multiple users in the same time slot and frequency band and thus eliminate the need for guard bands and guard intervals to provide significant capacity improvements. Therefore, the research on its performance has been increasing since it is a desirable candidate for next‐generation wireless networks. Compared with orthogonal multiple access (OMA) techniques, the reliability of NOMA is lower since multiple access interference increases as the number of users is increased. Most of the previous studies on NOMA systems only consider the impact of fading in the transmission medium; however, more realistic channel models include both fading and shadowing. In this paper, outage probability (OP), average channel capacity, and symbol error rate (SER) for uplink NOMA over generalized‐K fading are derived analytically for the arbitrary number of users and then verified by Monte Carlo simulations.
Metal Complexes of the Perfluorinated Trityl Alkoxide [(C6F5)3CO]−
Authors: Kögel Julius F. , Feige Felix , Duvinage Daniel , Lork Enno , Timoshkin Alexey Y. , Beckmann Jens 
Published: December 2021

AbstractHerein we investigate sodium, magnesium, zinc, titanium, silver and thallium complexes based on the perfluorinated trityl alcohol (C6F5)3COH (1) with respect to their structural motifs. The coordination compounds were prepared by alkane or salt elimination reactions in non‐polar solvents. XRD analysis revealed a monomeric structure for Ti[OC(C6F5)3]2[OCH(CH3)2]2 (2), dimers for [Mg(OC(C6F5)3)2]2 (3), [Zn(OC(C6F5)3)Et]2 (4) and [Tl(OC(C6F5)3)]2 (5) as well as tetrameric structural motifs for the homoleptic sodium and silver compounds with the general formula [M(OC(C6F5)3)]4: A distorted [NaO]4 cube is observed for [Na(OC(C6F5)3)]4 (6) whereas [Ag(OC(C6F5)3)]4 (7) exhibits a planar [AgO]4 square. Metal fluorine contacts play an important role in all molecular structures presented herein.
Copper Mediated Intramolecular vs. Intermolecular Oxygenations: The Spacer makes the Difference!
Authors: Petrillo Alexander , Hoffmann Alexander , Becker Jonathan , Herres‐Pawlis Sonja , Schindler Siegfried 
Published: December 2021

AbstractCopper complexes in combination with dioxygen are important as potential catalytic systems for regio‐ and stereoselective aerobic oxygenations of aromatic and aliphatic C−H bonds at ambient temperatures. In that context we herein describe a copper(I) complex with an imine ligand derived from (+)‐camphor and 2‐(2‐aminoethyl)pyridine that forms a bis(μ‐hydroxido) dicopper complex upon reaction with dioxygen at room temperature. It is detectable by UV‐vis for several hours up to a few days, depending on the solvent and could be structurally characterized. In contrast to previous observations this complex rather oxygenates acetone or thioanisole as external substrates instead of undergoing an intramolecular ligand hydroxylation.
Mechanistically Guided One Pot Synthesis of Phosphine‐Phosphite and Its Implication in Asymmetric Hydrogenation
Authors: Sen Anirban , Kumar Rohit , Pandey Swechchha , Vipin Raj K. , Kumar Pawan , Vanka Kumar , Chikkali Samir H. 
Published: December 2021

AbstractAlthough hybrid bidentate ligands are known to yield highly enantioselective products in asymmetric hydrogenation (AH), synthesis of these ligands is an arduous process. Herein, a one pot, atom‐economic synthesis of a hybrid phosphine‐phosphite (L1) is reported. After understanding the reactivity difference between an O‐nucleophile versus C‐nucleophile, one pot synthesis of Senphos (L1) was achieved (72 %). When L1 was treated with [Rh], 31P NMR revealed bidentate coordination to Rh. Senphos, in the presence of rhodium, catalyzes the AH of Methyl‐2‐acetamido‐3‐phenylacrylate and discloses an unprecedented turn over frequency of 2289, along with excellent enantio‐selectivity (92 %). The generality is demonstrated by hydrogenating an array of alkenes. The AH operates under mild conditions of 1–2 bar H2 pressure, at room temperature. The practical relevance of L1 is demonstrated by scaling‐up the reaction to 1 g and by synthesizing DOPA, a drug widely employed for the treatment of Parkinson's disease. Computational insights indicate that the R isomer is preferred by 3.8 kcal/mol over the S isomer.
Improving reliability of logging process: A Bohai Bay case study
Authors: Wang Erbo , Zhang Qin , Qiu Rui , Zhang Hao , Zhang Haoran 
Published: December 2021

AbstractDrilling and logging are important links in oil and gas development, and the accurate acquisition of operation data directly affects the development efficiency of oil and gas reserves. Under the dual pressure of safety and economy, it is essential to find out how to improve the quality of logging, especially the quality of logging while drilling. This article focuses on logging technology applied in the Bohai Bay field. Drilling engineering data from several sites are analyzed to identify factors influencing the reliability performance of formation pressure tests. The analysis is conducted using the commercial drilling engineering software JewelSuite. Two types of main failure phenomena are summarized: lost seal, time out. Next, logging reliability improvement technologies are proposed based on the results of reliability analysis, such as resolution improvement, bottom hole assembly optimization, and on‐site construction operation procedures. These technologies can achieve more efficient and accurate formation pressure acquisition while providing important data for later productivity prediction and development. The practice has proved that the improved technologies can reduce failures by nearly 66.7%, and can also reduce cost by more than 33.84 M USD.
An efficient fire detection algorithm based on multi‐scale convolutional neural network
Authors: Cheng Yanying , Chen Ke , Bai Hui , Mou Chunjie , Zhang Yuchun , Yang Kai , Gao Yunji , Liu Yu 
Published: December 2021

SummaryVideo fire detection (VFD) technology has shown a broad application prospect with the popularization of camera monitoring systems. Since the initial stage is the best time for firefighting, it's crucial to develop a robust algorithm for early warning. In this paper, an efficient VFD fusion algorithm is presented. First, the fire candidate areas (FCA) are located quickly based on low‐level visual features to guarantee well timeliness. Furthermore, a multi‐scale convolutional neural network with spatial pyramid pooling is built and trained on the dedicated flame data set without the requirement of sample labeling. In this case, FCA with different aspect ratios and scales can be accurately identified. The method is fully tested on various databases of arbitrary‐sized images and videos. Experimental results show that the proposed fusion algorithm, in addition to improving the detection efficiency, also ensures the accurate identification of flames on different scales.
Do sentiment indices always improve the prediction accuracy of exchange rates?
Authors: Ito Takumi , Takeda Fumiko 
Published: December 2021

AbstractThis study aims to improve the prediction accuracy of the exchange rate model by changing how indices that capture market sentiment are constructed. We construct the sentiment indices (SIs) for the Japanese and American markets using the Google search volume index (SVI) for financial terms listed in the Japanese dictionary. For these SVIs, we select keywords based on the correlation between weekly changes in the yen–dollar rate and the SVI. We use 30, 20, and 10 keywords that are replaced at three different frequencies: 3 months, 6 weeks, and weekly. The training period is from January 2013 to June 2015, and the forecast period is from July 2015 to December 2017. We perform a rolling regression, which keeps the length of the reference period constant at 2 and a half years, based on the interest rate parity and autoregressive models for the predictions. We compare the prediction accuracy using the mean squared prediction error, Clark and West's tests of equal predictive accuracy, and the direction of change test. When the SIs are updated every 3 months and 6 weeks, neither the interest rate parity model nor the autoregressive model shows improved prediction accuracy, even if the SI is added. However, when the SIs are updated weekly, prediction accuracy improves in both the interest rate parity and the autoregressive models as the number of words used to construct the SI increases. We conclude that frequently updated SIs can improve the short‐term prediction accuracy, while SIs updated less frequently may not.
Early‐life thermal stress mediates long‐term alterations in hypothalamic microglia
Authors: Ben‐Nun Osher , Kisliouk Tatiana , Marco Asaf , Rosenberg Tali , Meiri Noam 
Published: December 2021

AbstractStressful environmental events in early life have long‐lasting consequences on later stress responses. We previously showed that heat conditioning of 3‐day‐old chicks during the critical period of heat‐response development leads to heat vulnerability later in life. Here we assessed the role of early‐life heat stress on the inflammatory response in the chick anterior hypothalamus (AH), focusing on hypothalamic microglia. We identified the microglial cell population in the chick AH using anti‐KUL01 and anti‐CD45 antibodies. Specific microglial features were also confirmed by expression of their signature genes. Under normal environmental conditions, hypothalamic microglia isolated from lipopolysaccharide (LPS)‐injected chicks displayed a classical activated proinflammatory profile accompanied by a decreased homeostatic signature, demonstrating similarity of immune response with mammalian microglial cells. In accordance with our previous observations, conditioning of 3‐day‐old chicks under high ambient temperature decreased the number of newborn cells in the AH, among them microglial precursors. Although heat exposure did not affect microglial cell viability, it had a long‐term impact on LPS‐induced inflammatory response. Exposure to harsh heat led to heat vulnerability, and attenuated recruitment of peripheral monocytes and T cells into the AH following LPS challenge. Moreover, heat conditioning altered microglial reactivity, manifested as suppressed microglial activation in response to LPS. Innate immune memory developed by heat conditioning might underlie suppression of the microglial response to LPS challenge. We describe alterations in genome‐wide CpG methylation profile of hypothalamic microglia, demonstrating probable epigenetic involvement in the reprogramming of microglial function, leading to heat‐induced inflammatory cross‐tolerance.
Deficits of Public Deliberation in U.S. Oversight for Gene Edited Organisms
Authors: Kuzma Jennifer 
Published: December 2021

AbstractEnvironmental releases of gene edited (GEdOs) and gene drive organisms (GDOs) will likely occur under conditions of high uncertainty and in complex socioecological systems. Therefore, public deliberation is especially important to account for diverse interpretations of safety, risks, and benefits; to draw on experiential and public wisdom in areas of proposed release; to ameliorate dangers of technological optimism; and to increase the public legitimacy of decisions. Yet there is a “democratic deficit” in the United States' oversight system for GEdOs and GDOs, as unconflicted experts, publics, and skeptical stakeholders are most often excluded from decision‐making and unavailable to critically examine potential risks and benefits or raise broader concerns about socioeconomic or cultural impacts. This article argues for the need to open up decision‐making for GEdOs and GDOs, discusses the challenges for doing so within the current oversight framework, and finally, proposes institutional, policy, and attitudinal changes that are likely important for overcoming barriers to public deliberation.