bluuebunny/crossref_metadata_2025_split huggingface dataset:
Controlled Ligand Exchange Between Ruthenium Organometallic Cofactor Precursors and a Naïve Protein Scaffold Generates Artificial Metalloenzymes Catalysing Transfer Hydrogenation
Authors: Biggs George S. , Klein Oskar James , Maslen Sarah L. , Skehel J. Mark , Rutherford Trevor J. , Freund Stefan M. V. , Hollfelder Florian , Boss Sally R. , Barker Paul D. 
Published: February 2021

AbstractMany natural metalloenzymes assemble from proteins and biosynthesised complexes, generating potent catalysts by changing metal coordination. Here we adopt the same strategy to generate artificial metalloenzymes (ArMs) using ligand exchange to unmask catalytic activity. By systematically testing RuII(η6‐arene)(bipyridine) complexes designed to facilitate the displacement of functionalised bipyridines, we develop a fast and robust procedure for generating new enzymes via ligand exchange in a protein that has not evolved to bind such a complex. The resulting metal cofactors form peptidic coordination bonds but also retain a non‐biological ligand. Tandem mass spectrometry and 19F NMR spectroscopy were used to characterise the organometallic cofactors and identify the protein‐derived ligands. By introduction of ruthenium cofactors into a 4‐helical bundle, transfer hydrogenation catalysts were generated that displayed a 35‐fold rate increase when compared to the respective small molecule reaction in solution.
Au–Ag Bimetallic Catalysis: 3‐Alkynyl Benzofurans from Phenols via Tandem C−H Alkynylation/Oxy‐Alkynylation
Authors: Hu Long , Dietl Martin C. , Han Chunyu , Rudolph Matthias , Rominger Frank , Hashmi A. Stephen K. 
Published: February 2021

AbstractThe development of new methodologies enabling a facile access to valuable heterocyclic frameworks still is an important subject of research. In this context, we describe a dual catalytic cycle merging C−H alkynylation of phenols and oxy‐alkynylation of the newly introduced triple bond by using a unique redox property and the carbophilic π acidity of gold. Mechanistic studies support the participation of a bimetallic gold–silver species. The one‐pot protocol offers a direct, simple, and regio‐specific approach to 3‐alkynyl benzofurans from readily available phenols. A broad range of substrates, including heterocycles, is transferred with excellent functional group tolerance. Thus, this methodology can be used for the late‐stage incorporation of benzofurans.
Making Waxy Salts in Water: Synthetic Control of Hydrophobicity for Anion‐Induced and Aggregation‐Enhanced Light Emission
Authors: Kim Soohyung , Kim Jongmin , Lee Dongwhan 
Published: February 2021

AbstractWe show that multipodal polycationic receptors function as anion‐responsive light‐emitters in water. Prevailing paradigms utilize rigid holes and cavities for ion recognition. We instead built open amphiphilic scaffolds that trigger polar‐to‐nonpolar environment transitions around cationic fluorophores upon anion complexation. This ion‐pairing and aggregation event produces a dramatic enhancement in the emission intensity, as demonstrated by perchlorate as a non‐spherical hydrophobic anion model. A synergetic interplay of C−H⋅⋅⋅anion hydrogen bonding and tight anion–π+contacts underpins this supramolecular phenomenon. By changing the aliphatic chain length, we demonstrate that the response profile and threshold of this signaling event can be controlled at the molecular level. With appropriate molecular design, inherently weak, ill‐defined, and non‐directional van der Waals interaction enables selective, sensitive, and tunable recognition in water.
Acetate ion augmented fluorescence sensing of Zn2+ by Salen‐based probe, AIE character, and application for picric acid detection
Authors: Das Bhriguram , Dolai Malay , Dhara Anamika , Mabhai Subhabrata , Jana Atanu , Dey Satyajit , Misra Ajay 
Published: February 2021

AbstractCounter anion‐triggered metal ion detection has been rarely reported by fluorimetric method. To address this challenging issue, a fluorescent probe (H2L) has been synthesized from bromo‐salicylaldehyde and hydrazine hydrate, and structurally characterized by single crystal X‐ray diffraction. The probe shows very weak fluorescence itself. However, its emission intensity increases in the presence of Zn2+ over other metal ions. Surprisingly, the emission profile of this probe in presence of Zn2+ is augmented only when acetate anion (OAc¯) is present as counter anion, that allows for precise quantitative analysis by spectroscopic studies. The compositions and complexation among the probe, Zn2+ ion, and OAc¯ are supported by ESI‐MS, 1H‐NMR, and Job's plot. Based on these studies, it is confirmed that the binding ratio between probe: metal is 1:2 and the detection limit (LOD) for the Zn2+ is 2.18 µM. The probe is capable of recognizing Zn2+ ion in the wide range of pH∼6.5‐9.5, and it could be efficiently recycled by EDTA. Furthermore, the combinatorial molecular logic gate and memory device have been constructed from the fluorescent behavior of H2L with Zn2+, OAc¯, and EDTA input as based on NOT and AND gates. Interestingly, the aggregation‐induced emission (AIEE) phenomenon is also perceived with greater than 50% water content in organic water mixtures, which are then useful for the detection of picric acid often used as explosive.
Erdbebensicherheit von Stahlbeton‐Bestandstragwerken im Kontext der Eurocode‐8‐Anwendung
Authors: Akkermann Jan 
Published: February 2021

AbstractErdbeben stellen eine in Deutschland seltene, aber grundsätzlich mögliche Gefährdung für Gebäude und Teile davon dar. Mit Veröffentlichung neuester Erkenntnisse zur Erdbebengefährdung in Deutschland ging eine Neubewertung des Einwirkungsniveaus im Nationalen Anhang zum Eurocode 8 einher, die in vielen erdbebengefährdeten Regionen höhere Bemessungsbelastungen zur Folge hat. Seit Einführung normativer Vorgaben zur Erdbebenbemessung hat das Einwirkungsniveau zumeist kontinuierlich zugenommen. Für Bestandstragwerke aus Stahlbeton stellt sich aus Gründen der Verkehrssicherheit generell und bei Tragwerkseingriffen aufgrund von ressourcenschonenden Revitalisierungen im Speziellen die Frage nach der Verhältnismäßigkeit zwischen Bestandsschutz und Sicherungspflicht. Trotz grundsätzlich erdbebenkonformer Bauart mit duktilen Rahmen und Wandscheiben – insbesondere bei im Vergleich zur Vertikalbelastung geringem Horizontallastniveau – sind die vorhandenen Aussteifungssysteme zumeist nicht für die höheren Beanspruchungen nachzuweisen. Für den Bereich zwischen einer seismischen Mindestbeanspruchbarkeit und vollständigem Erdbebenwiderstand gegen aktuelle Einwirkungen wird eine risikobasierte Bewertung anhand von Erfüllungsfaktoren in Anlehnung an die schweizerische SIA 269/8 vorgeschlagen.
Accompanied anomalies in anal atresia or tracheo‐esophageal fistula: Comparison with or without VACTERL association
Authors: Ahn Ji Hyun , Choi Hee Joung 
Published: February 2021

AbstractPurposeWe evaluated the various accompanied malformations in patients with anal atresia or tracheoesophageal fistula (TEF). Furthermore, we determined the prevalence of VACTERL association and compared the clinical findings with those of patients without VACTERL association.MethodsWe enrolled the patients with anal atresia or TEF with/without esophageal atresia. We collected the patient data pertaining to accompanied vertebral, cardiovascular, renal or limb anomalies, single umbilical artery, maternal diabetes mellitus or drug history, and gene research.ResultsA total 155 patients (65 boys and 90 girls) were enrolled with 147 cases of anal atresia, 3 cases of TEF, and 5 cases of anal atresia with TEF. The prevalence of accompanied anomalies was 67.1% in cardiovascular, 27.1% in renal, 9.7% in vertebral, 2.6% in limb anomalies, and 3.9% in single umbilical artery. Thirty‐six (23.2%) patients were diagnosed with VACTERL association. The patients with VACTERL association had a significantly higher number of male patients (58.3 vs. 37.0%, p = .033) and single umbilical artery (11.1 vs. 1.7%, p = .026), and had a significantly lower birth weight (2.8 vs. 3.1 kg, p = .033) than the patients without VACTERL association. Genetic studies were performed in 111 patients, and 8 (7.2%) had chromosomal abnormalities—3 in VACTERL and 5 in no VACTERL group.ConclusionWe recommend a careful evaluation for VACTERL association in patients with anal atresia or TEF. It is particularly important to screen for a single umbilical artery for features of VACTERL association as well as for other congenital anomalies.
Correcting the bias of the net benefit estimator due to right‐censored observations
Authors: Péron Julien , Idlhaj Maryam , Maucort‐Boulch Delphine , Giai Joris , Roy Pascal , Collette Laurence , Buyse Marc , Ozenne Brice 
Published: February 2021

AbstractGeneralized pairwise comparisons (GPCs) are a statistical method used in randomized clinical trials to simultaneously analyze several prioritized outcomes. This procedure estimates the net benefit (Δ). Δ may be interpreted as the probability for a random patient in the treatment group to have a better overall outcome than a random patient in the control group, minus the probability of the opposite situation. However, the presence of right censoring introduces uninformative pairs that will typically bias the estimate of Δ toward 0. We propose a correction to GPCs that estimates the contribution of each uninformative pair based on the average contribution of the informative pairs. The correction can be applied to the analysis of several prioritized outcomes. We perform a simulation study to evaluate the bias associated with this correction. When only one time‐to‐event outcome was generated, the corrected estimates were unbiased except in the presence of very heavy censoring. The correction had no effect on the power or type‐1 error of the tests based on the Δ. Finally, we illustrate the impact of the correction using data from two randomized trials. The illustrative datasets showed that the correction had limited impact when the proportion of censored observations was around 20% and was most useful when this proportion was close to 70%. Overall, we propose an estimator for the net benefit that is minimally affected by censoring under the assumption that uninformative pairs are exchangeable with informative pairs.
Sub‐second heat inactivation of coronavirus using a betacoronavirus model
Authors: Jiang Yuqian , Zhang Han , Wippold Jose A. , Gupta Jyotsana , Dai Jing , de Figueiredo Paul , Leibowitz Julian L. , Han Arum 
Published: February 2021

AbstractHeat treatment denatures viral proteins that comprise the virion, making the virus incapable of infecting a host. Coronavirus (CoV) virions contain single‐stranded RNA genomes with a lipid envelope and four proteins, three of which are associated with the lipid envelope and thus are thought to be easily denatured by heat or surfactant‐type chemicals. Prior studies have shown that a temperature as low as 75°C with a treatment duration of 15 min can effectively inactivate CoV. The degree of CoV heat inactivation greatly depends on the length of heat treatment time and the temperature applied. With the goal of finding whether sub‐second heat exposure of CoV can sufficiently inactivate CoV, we designed and developed a simple fluidic system that can measure sub‐second heat inactivation of CoV. The system is composed of a stainless‐steel capillary immersed in a temperature‐controlled oil bath followed by an ice bath, through which virus solution can flow at various speeds. Flowing virus solution at different speeds, along with temperature control and monitoring system, allows the virus to be exposed to the desired temperature and treatment durations with high accuracy. Using mouse hepatitis virus, a betacoronavirus, as a model CoV system, we identified that 71.8°C for 0.51 s exposure is sufficient to obtain >5 Log10reduction in viral titer (starting titer: 5 × 107PFU/ml), and that when exposed to 83.4°C for 1.03 s, the virus was completely inactivated (>6 Log10reduction).
Autonomy and authority: Homeless service users' empowering experiences in housing first and staircase services
Authors: O'Shaughnessy Branagh R. , Greenwood Ronni Michelle 
Published: February 2021

AbstractAlthough Housing First (HF) has gained widespread support as a service model to end homelessness, staircase services (SS) continue to proliferate. Critics have argued that SS contribute to institutionalisation and neglect the structural causes of homelessness. However, HF employs an empowerment‐orientated approach which can reduce institutionalisation and enable service users to achieve their potential. In this study, we combined a conceptual framework of empowering service features with the capabilities approach to compare the experiences of service users in HF and SS in Ireland. We carried out four focus group discussions with service users in HF (n = 7) and SS (n = 8). Using thematic analysis, we identified three themes that represented participants' descriptions of services: support orientation, home is more than shelter and organisational and political participation. Autonomy‐orientated support and an emphasis on service user choice and housing afforded HF service users' empowering experiences. The authoritarian approach, and emphasis on housing readiness and provider expertise undermined SS service users' empowering experiences. Findings suggest how HF and SS service features shape service users' lived experiences and perceptions of services. Implications for policy and practice are discussed.
Protective Effects of 3,4‐Seco‐Lupane Triterpenes from Food Raw Materials of the Leaves of Eleutherococcus Senticosus and Eleutherococcus Sessiliflorus on Arrhythmia Induced by Barium Chloride
Authors: Zhao Yan , Wang Xu , Chen Chen , Shi Kun , Li Jianming , Du Rui 
Published: February 2021

AbstractAs a traditional wild vegetable and food raw material, the leaves of Eleutherococcus senticosus and Eleutherococcus sessiliflorus are rich in 3,4‐seco‐lupane triterpenes, including chiisanoside (CSS), divaroside (DVS), sessiloside‐A (SSA), and chiisanogenin (CSG). This study was conducted to evaluate the anti‐arrhythmic effects of these 3,4‐seco‐lupane triterpenes. Evaluation of the cytotoxicity of compounds was performed by measuring cell viability and apoptosis with the CCK‐8 assay. In vivo, arrhythmia was induced by rapid injection of BaCl2 via rat caudal vein. The occurrence time and duration of arrhythmias in rats were studied. The levels of SOD and MDA in serum, and Na+‐K+‐ATPase and Ca2+‐Mg2+‐ATPase in myocardial homogenate were detected by ELISA. The histopathological changes of rats myocardial were observed by HE staining. Changes in the expression of PKA and related proteins were detected by Western blot. The 3,4‐seco‐lupane triterpenes interactions with protein kinase A were analyzed by molecular docking. In the present study, we found that 3,4‐seco‐lupane triterpenes exhibited powerful anti‐arrhythmic activity, especially DVS completely relieved the ventricular arrhythmia induced by BaCl2. This study suggests that the leaves of E. senticosus and E. sessiliflorus might be used as functional food materials to prevent arrhythmia, and DVS can potentially be further developed as an anti‐arrhythmic drug.
Frontiers in Hybrid Ion Capacitors: A Review on Advanced Materials and Emerging Devices
Authors: Naskar Pappu , Kundu Debojyoti , Maiti Apurba , Chakraborty Priyanka , Biswas Biplab , Banerjee Anjan 
Published: February 2021

AbstractHybrid supercapacitors are the most desirable electrochemical energy storage devices, owing to their versatile and tunable performance characteristics, specifically in energy and power densities, towards applications in research and development. Construction‐wise, optimized assembly of batteries (energy devices) and supercapacitors (power devices) are the key for hybrid supercapacitors. Based on scientific advancements and technological achievements, hybrid ion capacitors are the most important segments in hybrid supercapacitors, as well as in the overall energy storage arena. Herein, opportunities and challenges of hybrid ion capacitors are intensively addressed in light of lithium‐ion, sodium‐ion, potassium‐ion, magnesium‐ion, calcium‐ion, zinc‐ion, and aluminum‐ion capacitors. The historical origins and their developmental pathways are identified for each type of capacitor. Possible classes of materials for every hybrid ion capacitor are discussed, and relevant mechanisms are demonstrated. These discussions reveal that a rich materials bank exists for lithium‐ion, sodium‐ion, and zinc‐ion capacitors, but the same is not applicable for potassium‐ion, magnesium‐ion, calcium‐ion, and aluminum‐ion capacitors. Consequently, such hybrid ion capacitors have not yet reached the level of commercial benchmarks like lithium‐ion, sodium‐ion, and zinc‐ion capacitors. However, this Review focuses on mostly full‐cell device data that synchronize the performances of practical scaled‐up systems. Several electrolytes based on solvent media (aqueous, organic, and ionic liquid), phase (liquid, gel, and solid), and redox activity (active and passive) are exemplified in different sections of hybrid ion capacitors. Various device constructions are elaborated upon, such as liquid‐electrolyte devices, polymeric gel devices, all‐solid‐state devices, flexible‐cum‐wearable devices, microdevices, solar‐charging devices, and so forth. The Review culminates with feasible future directions for the commercial success of hybrid ion capacitors, which are in the nascent stages of developments. To the best of our knowledge, it is the first holistic account of hybrid ion capacitors from their historical perspectives to present developments.
Time‐traveling colors: Artisanal dreams and digital fabrication
Authors: Kutlu Mete 
Published: February 2021

AbstractIn the 15th century, the miniaturists of the Timurid court in Herat conceive colors that seem to be made of pure light, without weight and volume. Their luminous colors synthesize a unique worldview from the anti‐materialistic teachings of Mani, the Sufi “world of imagination” and the alchemists' principles of transmutation. Five centuries later, our digital technologies seem to offer us such disembodied colors, which used to be the artistic dream of an artisanal culture. Pixels replace pigments, light‐colors replace matter‐colors. With the booming animation and game cultures, Tokyo becomes one of the first places that pixels invade in the 80s. A group of Japanese architects and artists seeks to express in their creations the ethereal dimension of the pixels' electronic light. Through a spatio‐temporal leap, the miniatures, as a historical reference point, reveals the emerging chromatic trends in contemporary architecture and visual culture. Could the invention of pixels be after all, stemming from an ancestral aspiration of mankind based on the sensorial and intelligible duality of his nature?
Classification of some chemical drugs by genetic algorithm and deep neural network hybrid method
Authors: Karakaplan Mustafa , Avcu Fatih Mehmet 
Published: February 2021

SummaryDeep neural networks (DNN) and genetic algorithm (GA) are gaining importance quickly with many successful applications in the field of science and technology. They are indispensable tool for the numerical solution of difficult problems. It is possible to optimize DNNs using the GA and this combination can be used to classify data. In this article, some drugs are classified by Monte Carlo sampling with combination of GA and DNN due to stochastic nature of the domain, exponential number of variables and small number of chemical species. In addition to the values obtained from the databases of selected drugs, molecular dynamic and ab initio molecular mechanical calculation results were also used. The aim of this study is to generalize the molecular classification with the data obtained from chemical databases as well as molecular docking results by using the combination of deep learning and GA and its usability in drug design. The selected drugs are some agonist and antagonist drugs that bind to dopamine receptors, which are widely studied and well known in the literature. To train the DNN, input datasets were chosen by the GA framework written in pure Python named PyEvolve. Classification of drugs has been analyzed with the focus on orbital energies and docking results. It is possible to use this algorithm in many in silico calculations such as affinity and separation processes. The reliability of the algorithm was tested with the results given in the literature and the expected values were estimated at 93.8%.
Supramolecular Coordination Complexes as Optical Biosensors
Authors: Dey Nilanjan , Haynes Cally J. E. 
Published: February 2021

AbstractIn recent years, luminescent supramolecular coordination complexes (SCCs), including 2D‐metallacycles and 3D‐metallacages have been utilised for biomolecular analysis. Unlike small‐molecular probes, the dimensions, size, shape, and flexibility of these complexes can easily be tuned by combining ligands designed with particular geometries, symmetries and denticity with metal ions with strong geometrical binding preferences. The well‐defined cavities that result, in combination with the other non‐covalent interactions that can be programmed into the ligand design, facilitate great selectivity towards guest binding. In this Review we will discuss the application of luminescent metallacycles and cages in the binding and detection of a wide range of biomolecules, such as carbohydrates, proteins, amino acids, and biogenic amines. We aim to explore the effect of the structural diversity of SCCs on the extent of biomolecular sensing, expressed in terms of sensitivity, selectivity and detection range.
A Refined Protocol for Coronary Artery Ligation in the Neonatal Mouse
Authors: De Villiers Carla , Riley Paul R. 
Published: February 2021

AbstractThe neonatal mouse heart can regenerate following myocardial infarction (MI), a capacity that is lost after 7 days, providing a model system to study tissue regeneration and the transition to adult wound healing. MI can be induced in neonatal mice surgically by coronary artery ligation. In this protocol, neonates are anesthetized using a combination of inhaled isoflurane anesthesia and induced hypothermia, a significant ethical refinement over previous protocols. A lateral thoracotomy is performed, and an 8‐0 suture is used to ligate an area below the left atrium to induce MI. The ribs and skin are closed using 7‐0 sutures, and the pup is rapidly rewarmed with a supply of oxygen. Once recovered, the pup is cleaned and rolled in a fecal bath to mask the smell of surgical interference before being returned to the mother. The surgical procedure is expected to take 10 to 15 min per pup, with a further 5 min for recovery. A dedicated assistant for recovery of pups is recommended to streamline the procedure. © 2021 Wiley Periodicals LLC.This article was corrected on 19 July 2022. See the end of the full text for details.