bluuebunny/crossref_metadata_2025_split huggingface dataset:
Identification of Kinetic and Spectroscopic Signatures of Copper Sites for Direct Oxidation of Methane to Methanol
Authors: Sushkevich Vitaly L. , Artsiusheuski Mikalai , Klose Daniel , Jeschke Gunnar , van Bokhoven Jeroen A. 
Published: April 2021

AbstractCopper‐exchanged zeolites of different topologies possess high activity in the direct conversion of methane to methanol via the chemical looping approach. Despite a large number of studies, identification of the active sites, and especially their intrinsic kinetic characteristics remain incomplete and ambiguous. In the present work, we collate the kinetic behavior of different copper species with their spectroscopic identities and track the evolution of various copper motifs during the reaction. Using time‐resolved UV/Vis and in situ EPR, XAS, and FTIR spectroscopies, two types of copper monomers were identified, one of which is active in the reaction with methane, in addition to a copper dimeric species with the mono‐μ‐oxo structure. Kinetic measurements showed that the reaction rate of the copper monomers is somewhat slower than that of the dicopper mono‐μ‐oxo species, while the activation energy is two times lower.
Isoretikuläre Kristallisation von hochporösen kubischen kovalentorganischen Käfigverbindungen**
Authors: Ivanova Svetlana , Köster Eva , Holstein Julian J. , Keller Niklas , Clever Guido H. , Bein Thomas , Beuerle Florian 
Published: April 2021

AbstractModulare Netzwerke mit definierten Porenstrukturen in mikroskaligen Domänen ergeben maßgeschneiderte poröse Materialien. Für durchlässige molekulare Feststoffe lässt sich die Fernordnung nach einer Desolvatisierung jedoch nur schwer aufrechterhalten, da die Packung typischerweise nur von schwachen supramolekularen Wechselwirkungen geprägt wird. Hier stellen wir zwei Serien von Nanowürfeln vor, die durch Cokondensation von zwei verschiedenen Hexahydroxytribenzotriquinacenen (TBTQs) und Benzol‐1,4‐diboronsäuren (BDBAs) mit unterschiedlichen linearen Alkylketten in 2,5‐Position gebildet werden. n‐Butyl‐Gruppen an der apikalen Position der TBTQ‐Ecken führen zu löslichen Modellverbindungen, die durch Massenspektrometrie und NMR‐Spektroskopie analysiert wurden. Dagegen kristallisierten methylsubstituierte Käfige spontan als isostrukturelle und hochporöse Feststoffe mit BET‐Oberflächen bis zu 3426 m2 g−1und Porenvolumina bis zu 1.84 cm3 g−1. Röntgenbeugungsexperimente und Sorptionsmessungen offenbarten ein komplexes kubisches System alternierender Mikro‐ und Mesoporen von 0.97 bis 2.2 nm, deren Größen durch die Alkylsubstituenten am BDBA‐Linker genau einstellbar sind.
Stabilization of an Enantiopure Sub‐monolayer of Helicene Radical Cations on a Au(111) Surface through Noncovalent Interactions
Authors: Giaconi Niccolò , Sorrentino Andrea Luigi , Poggini Lorenzo , Lupi Michela , Polewczyk Vincent , Vinai Giovanni , Torelli Piero , Magnani Agnese , Sessoli Roberta , Menichetti Stefano , Sorace Lorenzo , Viglianisi Caterina , Mannini Matteo 
Published: April 2021

AbstractIn the past few years, the chirality and magnetism of molecules have received notable interest for the development of novel molecular devices. Chiral helicenes combine both these properties, and thus their nanostructuration is the first step toward developing new multifunctional devices. Here, we present a novel strategy to deposit a sub‐monolayer of enantiopure thia[4]helicene radical cations on a pre‐functionalized Au(111) substrate. This approach results in both the paramagnetic character and the chemical structure of these molecules being maintained at the nanoscale, as demonstrated by in‐house characterizations. Furthermore, synchrotron‐based X‐ray natural circular dichroism confirmed that the handedness of the thia[4]helicene is preserved on the surface.
Asymmetric Palladium‐Catalyzed Oxycarbonylation of Terminal Alkenes: Efficient Access to β‐Hydroxy Alkylcarboxylic Acids
Authors: Tian Bing , Li Xiang , Chen Pinhong , Liu Guosheng 
Published: April 2021

AbstractA novel PdII‐catalyzed enantioselective oxycarbonylation of alkenes has been established. The ligand with an ethyl group at the C‐6 position of Pyox plays a significant role in the intermolecular oxypalladation process, leading to high reactivity and excellent enantioselective control. Compared to the conventional methods, the reaction itself features alkenes as easily prepared starting materials, mild and operationally simple reaction conditions, and insensitivities to air and water. Moreover, this method allows for broad alkene substrate scope, excellent regio‐ and enantioselectivities, scalabilities and a wide array of applications, and provides a useful route for the convenient and straightforward synthesis of chiral β‐hydroxy alkylcarboxylic acids/esters.
Porous Covalent Organic Polymers for Efficient Fluorocarbon‐Based Adsorption Cooling
Authors: Zheng Jian , Wahiduzzaman Mohammad , Barpaga Dushyant , Trump Benjamin A. , Gutiérrez Oliver Y. , Thallapally Praveen , Ma Shengqian , McGrail B. Peter , Maurin Guillaume , Motkuri Radha Kishan 
Published: April 2021

AbstractAdsorption‐based cooling is an energy‐efficient renewable‐energy technology that can be driven using low‐grade industrial waste heat and/or solar heat. Here, we report the first exploration of fluorocarbon adsorption using porous covalent organic polymers (COPs) for this cooling application. High fluorocarbon R134a equilibrium capacities and unique overall linear‐shaped isotherms are revealed for the materials, namely COP‐2 and COP‐3. The key role of mesoporous defects on this unusual adsorption behavior was demonstrated by molecular simulations based on atomistic defect‐containing models built for both porous COPs. Analysis of simulated R134a adsorption isotherms for various defect‐containing atomistic models of the COPs shows a direct correlation between higher fluorocarbon adsorption capacities and increasing pore volumes induced by defects. Combined with their high porosities, excellent reversibility, fast kinetics, and large operating window, these defect‐containing porous COPs are promising for adsorption‐based cooling applications.
Accidental systemic administration of 1 litre of cardioplegia solution during paediatric cardiac surgery
Authors: Newington D. F. , Barker C. L. 
Published: April 2021

SummaryCardioplegia is used to induce cardiac arrest in order to facilitate cardiac surgery in patients supported by cardiopulmonary bypass. It is administered directly into the coronary vessels after the heart has been isolated from the systemic circulation. We describe the case of a 9‐year‐old boy who mistakenly received 1 l of high strength St Thomas’ Harefield cardioplegia solution delivered into the systemic circulation during cardiac surgery. Although the patient’s heart did not stop, the subsequent physiological derangements were severe. The presenting features were refractory hypotension and dilutional anaemia along with severe hyperkalaemia, hypermagnesaemia and hyperchloraemic metabolic acidosis. Local anaesthetic systemic toxicity from the procaine contained within the cardioplegia solution was also a concern. Treatment required vasopressor administration and an extended period of cardiopulmonary bypass while serum electrolyte concentrations were corrected by haemodiafiltration. The systemic administration of cardioplegia solution is a rare but important iatrogenic clinical emergency that anaesthetists working in cardiac centres should be aware of. This case demonstrates that full recovery is possible.
Ultrasound‐guided sacral multifidus plane block for analgesia following excision of sacrococcygeal teratoma in two neonates
Authors: Mahajan R. , Gulati S. , Gupta K. , Jain K. , Bloria S. , JItendra M. 
Published: April 2021

SummaryPeri‐operative pain management in the neonate with a sacrococcygeal teratoma poses significant challenges to the anaesthetist. Involvement of the sacrococcygeal area by the tumour often prevents the use of conventional regional anaesthetic techniques such as caudal or epidural analgesia, with a subsequent reliance on intravenous opioids and paracetamol. Since opioids are associated with respiratory depression, constipation and urinary retention, there is high incidence of opiophobia with consequent inappropriate dosage prescription, particularly in the paediatric population. We describe the use of an ultrasound‐guided sacral multifidus plane block in two neonates undergoing surgical excision of sacrococcygeal teratoma. The block is technically easy to perform and also avoids traversing critical structures. Hence, it may be regarded as a promising analgesic technique for painful interventions in the sacrococcygeal area.
Design, synthesis, and catalytic evaluation of aluminum‐incorporated magnetic core–shell mesoporous microsphere catalyst NiFe2O4@SiO2@Al‐MS for the synthesis of functionalized indenopyrazolones
Authors: Mirheidari Mahnaz , Safaei‐Ghomi Javad 
Published: April 2021

A core–shell structured magnetic metal‐mesoporous microsphere materials NiFe2O4@SiO2@Al‐MS in which magnetic particles of NiFe2O4 are core and ordered mesoporous silica are shell, incorporated with aluminum to modify acid‐catalyzed reactions. The catalyst was synthesized by Pluronic P123 as a first surfactant and a small quantity of cetrimonium bromide as a template for assistant in acidic medium to create a porous layer. The structural characterization of the catalyst was assessed by Fourier transform infrared (FT‐IR), scanning electron microscopy (SEM), X‐ray diffraction (XRD), energy‐dispersive X‐ray (EDX), vibrating‐sample magnetometer (VSM), and Brunauer–Emmett–Teller (BET) analyses. The catalyst demonstrated considerable magnetic properties, a unique mesoporous structure with great surface area (370.36 m2 g−1), high‐value recovery, and reusability. The catalyst performance was evaluated for the synthesis of indenopyrazolones via the condensation of ninhydrin, phenylhydrazine, and various aldehydes. The mild conditions for the synthesis, easy workup, and short reaction time are the considerable benefits of the reaction in the presence of Nife2O4@SiO2@Al‐MS as a catalyst.
Integration of clinical anatomical sciences in medical education: Design, development and implementation strategies
Authors: Khalil Mohammed K. , Giannaris Eustathia Lela , Lee Vaughan , Baatar Dolgor , Richter Saskia , Johansen Krista S. , Mishall Priti L. 
Published: April 2021

AbstractFor the last 20 years, undergraduate medical education has seen a major curricular reform movement toward integration of basic and clinical sciences. The rationale for integrated medical school curricula focuses on the application of knowledge in a clinical context and the early ability to practice key skills such as critical thinking and clinical problem‐solving. The method and extent of discipline integration can vary widely from single sessions to entire programs. A challenge for integrated curricula is the design of appropriate assessments. The goal of this review is to provide a framework for clinical anatomy educators with definitions of integration, examples of existing integration models, strategies, and instructional methods that promote integration of basic and clinical sciences.
Risk factors for neonatal brachial plexus palsy attributed to anatomy, physiology, and evolution
Authors: Dunbar Donald C. , Vilensky Joel A. , Suárez‐Quian Carlos A. , Shen Peter Yi , Metaizeau Jean‐Paul , Supakul Nucharin 
Published: April 2021

AbstractThe inherent variable anatomy of the neonate and the uniquely‐shaped maternal birth canal that is associated with the evolution of human bipedalism constitute risk factors for neonatal brachial plexus palsy (NBPP). For example, those neonates with a prefixed brachial plexus (BP) are at greater risk of trauma due to lateral neck traction during delivery than those with a normal or postfixed BP. Compared to adults, neonates also have extremely large and heavy heads (high head: body ratio) set upon necks with muscles and ligaments that are weak and poorly developed. Accordingly, insufficient cranial stability can place large torques on the cervical spinal nerves. In addition, the pelvic changes necessary for habitual bipedal posture resulted in a uniquely‐shaped, obstruction‐filled, sinusoidal birth canal, requiring the human fetus to complete a complicated series of rotations to successfully traverse it. Furthermore, although there are many risk factors that are known to contribute to NBPP, the specific anatomy and physiology of the neonate, except for macrosomia, is not considered to be one of them. In fact, currently, the amount of lateral traction applied to the neck during delivery is the overwhelming legal factor that is used to evaluate whether a birth attendant is liable in cases of permanent NBPP. Here, we suggest that the specific anatomy and physiology of the neonate and mother, which are clearly not within the control of the birth attendant, should also be considered when assessing liability in cases of NBPP.
Affinity Selections of DNA‐Encoded Chemical Libraries on Carbonic Anhydrase IX‐Expressing Tumor Cells Reveal a Dependence on Ligand Valence
Authors: Oehler Sebastian , Catalano Marco , Scapozza Ilario , Bigatti Martina , Bassi Gabriele , Favalli Nicholas , Mortensen Michael R. , Samain Florent , Scheuermann Jörg , Neri Dario 
Published: April 2021

AbstractDNA‐encoded chemical libraries are typically screened against purified protein targets. Recently, cell‐based selections with encoded chemical libraries have been described, commonly revealing suboptimal performance due to insufficient recovery of binding molecules. We used carbonic anhydrase IX (CAIX)‐expressing tumor cells as a model system to optimize selection procedures with code‐specific quantitative polymerase chain reaction (qPCR) as selection readout. Salt concentration and performing PCR on cell suspension had the biggest impact on selection performance, leading to 15‐fold enrichment factors for high‐affinity monovalent CAIX binders (acetazolamide; KD=8.7 nM). Surprisingly, the homobivalent display of acetazolamide at the extremities of both complementary DNA strands led to a substantial improvement of both ligand recovery and enrichment factors (above 100‐fold). The optimized procedures were used for selections with a DNA‐encoded chemical library comprising 1 million members against tumor cell lines expressing CAIX, leading to a preferential recovery of known and new ligands against this validated tumor‐associated target. This work may facilitate future affinity selections on cells against target proteins which might be difficult to express otherwise.
First Total Synthesis of Phytoprostanes with Prostaglandin‐Like Configuration, Evidence for Their Formation in Edible Vegetable Oils and Orienting Study of Their Biological Activity
Authors: Smrček Jakub , Hájek Miroslav , Hodek Ondřej , Čížek Karel , Pohl Radek , Jahn Emanuela , Galano Jean‐Marie , Oger Camille , Durand Thierry , Cvačka Josef , Jahn Ullrich 
Published: April 2021

AbstractPhytoprostanes (PhytoP) are natural products, which form in plants under oxidative stress conditions from α‐linolenic acid. However, their epimers with relative prostaglandin configuration termed phytoglandins (PhytoG) have never been detected in Nature, likely because of the lack of synthetic reference material. Here, the first asymmetric total synthesis of such compounds, namely of PhytoGF1α (9‐epi‐16‐F1t‐PhytoP) and its diastereomer ent‐16‐epi‐PhytoGF1α (ent‐9,16‐diepi‐16‐F1t‐PhytoP), has been accomplished. The synthetic strategy is based on radical anion oxidative cyclization, copper(I)‐mediated alkyl‐alkyl coupling and enantioselective reduction reactions. A UHPLC‐MS/MS study using the synthesized compounds as standards indicates PhytoG formation at significant levels during autoxidation of α‐linolenic acid in edible vegetable oils. Initial testing of synthetic PhytoGs together with F1‐PhytoP and 15‐F2t‐IsoP derivatives for potential interactions with the PGF2α (FP) receptor did not reveal significant activity. The notion that PUFA‐derived oxidatively formed cyclic metabolites with prostaglandin configuration do not form to a significant extent in biological or food matrices has to be corrected. Strong evidence is provided that oxidatively formed PhytoG metabolites may be ingested with plant‐derived food, which necessitates further investigation of their biological profile.
Organofunktionelle Silane als Haftvermittler
Authors: Wolf Andreas T. 
Published: April 2021

ZusammenfassungHaftvermittler dienen zur Verbesserung der Adhäsion von flüssig applizierten, polymeren Werkstoffen zu Füllstoffen und Untergründen. Diese Aufgabe bewältigen sie, indem sie die Grenzfläche durch eine graduelle Übergangsphase ersetzen. Organofunktionelle Silane und oligomere Siloxane sind eine technisch besonders wichtige Klasse von Haftvermittlern. Der erste Teil dieser zweiteiligen Artikelserie befasst sich mit der Funktion und der Struktur, dem Chemismus und den Struktur‐Eigenschafts‐Beziehungen der organisch funktionalisierten Silanhaftvermittler. Insbesondere werden die bei der Anbindung eines organofunktionellen Alkoxysilans ablaufenden Teilreaktionen von Hydrolyse, intermolekulare Eigenkondensation (Oligomerisierung), Wasserstoffbrückenbildung und Kondensation mit Substrat oder Füllstoff sowie Reaktion mit dem organischen Polymer diskutiert.
Quantum computing: A measurement and analysis review
Authors: Gupta Mayank , Nene Manisha J. 
Published: April 2021

SummaryComputing methodologies with rapid proliferation and need for greater concurrency have evolved over the years from parallel and distributed computing to latest technologies like cloud computing. A paradigm shift in computing methodologies has been witnessed in the form of exponential speed up, optimization of problem solutions, and solvability of few classically unsolvable problems with emergence of quantum computing. The study in this article presents observations on executing basic quantum operations that play a vital role in quantum computing. The results and analysis demonstrate how parameters of time, deviation, and shots have a significant effect on outcomes of quantum circuits executed which can be a reference point for the community in general engaged in designing of quantum circuits, protocols, algorithms, and quantum hardware to leverage quantum characteristics and properties. The study by means of experimental use cases provides a rigorous review of qubit behavior, standard, and entangled qubit measurement with practical results over a simulator and real quantum hardware for variable qubit configurations using a selected platform of IBM Q Experience. With the paradigm shift from classical to quantum computing, this article provides basic but very vital observations which can be brought to use by anyone intending to build quantum applications.
Structure Formation and Coupling Reactions of Hexaphenylbenzene and Its Brominated Analog
Authors: Teeter Jacob D. , Costa Paulo S. , Dobner Christoph , Sarker Mamun , Sinitskii Alexander , Enders Axel 
Published: April 2021

AbstractThe on‐surface coupling of the prototypical precursor molecule for graphene nanoribbon synthesis, 6,11‐dibromo‐1,2,3,4‐tetraphenyltriphenylene (C42Br2H26, TPTP), and its non‐brominated analog hexaphenylbenzene (C42H30, HPB), was investigated on coinage metal substrates as a function of thermal treatment. For HPB, which forms non‐covalent 2D monolayers at room temperature, a thermally induced transition of the monolayer's structure could be achieved by moderate annealing, which is likely driven by π‐bond formation. It is found that the dibrominated carbon positions of TPTP do not guide the coupling if the growth occurs on a substrate at temperatures that are sufficient to initiate C−H bond activation. Instead, similar one‐dimensional molecular structures are obtained for both types of precursors, HPB and TPTP.
Analysis of intra‐observer and inter‐observer variability of pathologists for non‐benign thyroid fine needle aspiration cytology according to Bethesda system categories
Authors: Kuzan Taha Yusuf , Güzelbey Burcu , Turan Güzel Nalan , Kuzan Beyza Nur , Çakır Mehmet Semih , Canbey Ceren 
Published: April 2021

AbstractAimTo examine the intra‐ and inter‐observer variability for non‐benign thyroid cytological subcategories according to the Bethesda classification system after the second review.MethodsBetween November 2018 and May 2019, thyroid fine needle aspiration biopsies of 381 nodules were retrospectively evaluated. Among them, 74 non‐benign (category III‐VI) thyroid biopsies, analyzed according to the Bethesda system (pathologist 1:40 vs pathologist 2:34) by two independent pathologists, were reassessed by the same pathologists and by a cytopathologist. In this observer‐blinded study, weighted Cohen's kappa was used to assess the intra‐observer agreement, and Krippendorff's alpha was used to assess the inter‐observer agreement.ResultsAt the first and second evaluations of pathologists 1 and 2, the percentage agreement was 62.5% for pathologist 1 and 58.8% for pathologist 2. The intra‐observer agreement was substantial (κ = 0.705) for pathologist 1, and moderate (κ = 0.447) for pathologist 2. In the second evaluation of pathologist 1 and 2, which was compared with the cytopathologist, the agreement percentage of pathologist 1 with the cytopathologist was 50.0%, and that of pathologist 2 was 56.8%. The inter‐observer agreement was below the lowest acceptable limit for an overall agreement (α = 0.634) among the three raters. The inter‐observer agreement was only acceptable between the cytopathologist and the second pathologist, while it was low between the other raters. In the evaluation of the non‐benign nodules, the mean category score of the cytopathologist was 3.22 and lower than both pathologists (3.73 and 3.58, respectively).ConclusionsThe intra‐observer agreement of pathologists was moderate‐to‐substantial in the evaluation of non‐benign thyroid biopsies according to the Bethesda reporting system. However, the inter‐observer agreement was below the lowest acceptable limit when the cytopathologist was taken as a reference.
Proportioning of self‐centering energy dissipative braces
Authors: Xiao Yi , Eberhard Marc O. , Zhou Ying , Stanton John F. 
Published: April 2021

AbstractSelf‐centering energy dissipative (SCED) braces are designed to limit the maximum story drifts in buildings during earthquakes and to nearly eliminate residual drifts. The key properties of conventional braces (eg, strength, stiffness) can be determined with current seismic design procedures, but additional criteria are needed to select the hysteretic properties of SCED braces (eg, prestressing level, fuse activating deformation). Past investigations of the seismic performance of the SCED braced frames selected brace characteristics to match the hysteretic characteristics of buckling restrained braces (BRB). However, those characteristics may not be achieved because the performance of the SCED system is constrained by the elongation capacity of the post‐tensioned tendons. To develop recommendations for proportioning SCED braces, the researchers conducted a parametric study on the properties of two typical SCED systems, using a nine‐story steel braced frame office building. The seismic performances of the SCED systems were then compared with that of a BRB system including an analysis without property uncertainty and an analysis with uncertainty using Monte Carlo simulation. Based on the cost and seismic performances of SCED systems designed using various characteristics, recommendations are proposed for proportioning the SCED systems. Besides having much smaller residual drifts, the SCED systems had a smaller likelihood of exceeding a maximum story drift of 3% and less drift concentration compared with the BRB system, though they generated larger floor accelerations and forces in connections and adjacent members. The property uncertainty increased the residual drift of the SCED systems.