bluuebunny/crossref_metadata_2025_split huggingface dataset:
Visible‐Light‐Mediated Photoredox‐Catalyzed N‐Arylation of NH‐Sulfoximines with Electron‐Rich Arenes
Authors: Wimmer Alexander , König Burkhard 
Published: July 2018

AbstractThe direct C−H/N−H dehydrogenative cross‐coupling of NH‐sulfoximines with electron‐rich arenes was realized by oxidative visible‐light photoredox catalysis, applying 9‐mesityl‐10‐methylacridinium perchlorate as an organic photocatalyst. Sulfoximines display diverse desirable properties for medicinal chemistry and the pharmaceutical industry. However, their preparation is still challenging. Our reaction proceeds without sacrificial oxidant, at room temperature and is highly selective for the C−N bond forming reaction. The scope of the reaction includes mono‐ and multi‐alkylated and halogenated arenes, which are reacted with aromatic and aliphatic electron‐rich and electron‐poor NH‐sulfoximines, giving moderate to excellent yields of the N‐arylated sulfoximines. In addition, we successfully conducted the developed reaction on a gram scale (1.5 g). Mechanistic investigations show that both arene and NH‐sulfoximine interact with the excited‐state of the photocatalyst. We propose a radical‐based mechanism, where both the arene and the NH‐sulfoximine are photo‐oxidized to their respective radical intermediates. Radical‐radical cross‐coupling subsequently leads to the N‐arylated sulfoximine. Two electrons and two protons are released during the reaction and are subsequently converted into H2 by a proton‐reducing cobalt‐catalyst.magnified image
Adaptive differentiation among populations of the Mediterranean dry grassland species Brachypodium retusum: The role of soil conditions, grazing, and humidity
Authors: Vidaller Christel , Dutoit Thierry , Ibrahim Yosra , Hanslin Hans Martin , Bischoff Armin 
Published: July 2018

Premise of the StudyGenetic differentiation in plant species may result from adaptation to environmental conditions, but also from stochastic processes. The drivers selecting for local adaptation and the contribution of adaptation to genetic differentiation are often unknown. Restoration and succession studies have revealed different colonization patterns for Brachypodium retusum, a common Mediterranean grass. In order to understand these patterns, we tested population differentiation and adaptation to different environmental factors.MethodsStructured sampling of 12 populations from six sites and two soil types within site was used to analyze the spatial and environmental structure of population differentiation. Sampling sites differ in grazing intensity and climate. We tested germination and growth in a common garden. In subsets, we analyzed the differential response to stone cover, grazing and soil moisture.Key ResultsWe found significant differences among populations. The site explained population differentiation better than soil, suggesting a dominant influence of climate and/or genetic drift. Stone cover had a positive influence on seedling establishment, and populations showed a differential response. However, this response was not related to environmental differences between collection sites. Regrowth after clipping was higher in populations from the more intensively grazed Red Mediterranean soils suggesting an adaptation to grazing. Final germination was generally high even under drought, but germination response to differences in soil moisture was similar across populations.ConclusionsAdaptive population differentiation in germination and early growth may have contributed to different colonization patterns. Thus, the provenance of B. retusum needs to be carefully considered in ecological restoration.
Elektrokatalytische Oxidation von 5‐(Hydroxymethyl)furfural an Nickelborid mit großer Oberfläche
Authors: Barwe Stefan , Weidner Jonas , Cychy Steffen , Morales Dulce M. , Dieckhöfer Stefan , Hiltrop Dennis , Masa Justus , Muhler Martin , Schuhmann Wolfgang 
Published: July 2018

AbstractDie elektrochemische Oxidation des Bioraffinerieproduktes 5‐(Hydroxymethyl)furfural (HMF) zu der für die Polymerindustrie interessanten Plattformchemikalie 2,5‐Furandicarbonsäure (FDCA) gewinnt immer mehr Aufmerksamkeit. FDCA‐basierter Polymere, wie z. B. Polyethylenfuranoat (PEF), besitzen das Potential, großtechnisch verwendete und auf Erdöl basierende Polymere wie z. B. Polyethylenterephthalat (PET) nachhaltig zu ersetzen. Wir berichten über die hocheffiziente elektrokatalytische Oxidation von HMF zu FDCA an mit Nickelborid beschichtetem Nickelschaum. Die Elektrolyse von HMF bei konstantem Potential gekoppelt mit Hochleistungsflüssigkeitschromatographie (HPLC) zeigt einen hohen Faradayschen Wirkungsgrad von nahezu 100 % bezüglich FDCA als Oxidationsprodukt mit einer Ausbeute von 98.5 %. Operando‐ATR‐IR gekoppelt mit Elektrochemie belegt, dass HMF bevorzugt über das Intermediat 5‐Hydroxymethyl‐2‐furancarbonsäure (HMFCA) anstatt 2,5‐Diformylfuran (DFF) oxidiert wird. Diese Ergebnisse stimmen mit denen der HPLC‐Analyse überein. Die vorgestellte Studie berichtet nicht nur über Nickelborid als einen kostengünstigen Elektrokatalysator für die Oxidation von HMF zu FDCA, sondern gibt auch neue Einblicke in den Reaktionspfad.
Arene‐Limited Nondirected C−H Activation of Arenes
Authors: Wedi Philipp , van Gemmeren Manuel 
Published: July 2018

AbstractThe nondirected C(sp2)−H activation of simple arenes has advanced significantly in recent years through the discovery of new catalyst systems that are able to perform transformations with the arene as the limiting reagent. Important developments in catalyst and ligand design that have improved reactivity and selectivity are reviewed.
Enantioconvergent Biocatalytic Redox Isomerization
Authors: Liu Yu‐Chang , Merten Christian , Deska Jan 
Published: July 2018

AbstractAlcohol dehydrogenases can act as powerful catalysts in the preparation of optically pure γ‐hydroxy‐δ‐lactones by means of an enantioconvergent dynamic redox isomerization of readily available Achmatowicz‐type pyranones. Imitating the traditionally metal‐mediated “borrowing hydrogen” approach to shuffle hydrides across molecular architectures and interconvert functional groups, this chemoinspired and purely biocatalytic interpretation effectively expands the enzymatic toolbox and provides new opportunities in the assembly of multienzyme cascades and tailor‐made cellular factories.
COSMO SkyMed X‐Band SAR application – combined with thermal and RGB images – in the archaeological landscape of Roman Mellaria (Fuente Obejuna‐Córdoba, Spain)
Authors: Monterroso Checa Antonio , Martínez Reche Teresa 
Published: July 2018

AbstractCOSMO SkyMed offers high resolution X‐Band SAR (synthetic aperture radar) images. Despite its enormous potential, research investigating the possible uses in archaeology is still very scarce, especially of one which works solely with single date analysis starting with a single SAR scene. Therefore, we present the results of single date analysis developed with the acquisition of a CSK‐SPOTLIGHT X‐Band SAR image from Telespazio Iberica (Italian Space Agency) which examined 49 km2 of the territory of the ancient Roman city of Mellaria. This has allowed us to calibrate the possibilities of CSK X‐Band SAR in a geographic environment under climatic and atmospheric conditions other than those studied up to now. In addition, it is the first time that it has been used in an archaeological environment as dense as Spain. We tried to use the X‐Band SAR (1 m/pixel) image in order to detect archaeological traces in combination with thermal images (0.26 m/pixel) and RGB (0.03 m/pixel) taken airborne. We also used the RGB orthophotographs from the PNOA‐IGN (0.50 m/pixel) as a comparative method.
Bericht des Arbeitskreises Baugruben: Entwurf EB 85 und Anhang A 10
Authors: Hettler Achim , Becker Patrick , Kinzler Steffen 
Published: July 2018

AbstractDen Arbeitskreis „Baugruben“ der Deutschen Gesellschaft für Geotechnik erreichten in der Vergangenheit wiederholt Hinweise von Anwendern, in denen auf die Unterschiede beim Nachweis der vertikalen Tragfähigkeit von Baugrubenwänden zwischen 4. und 5. Auflage der Empfehlungen des Arbeitskreises „Baugruben“ (EAB) hingewiesen wurde. Vergleichsberechnungen zeigten, dass der Nachweis der vertikalen Tragfähigkeit nach 5. Auflage zu unwirtschaftlicheren Ergebnissen als nach 4. Auflage führt. Als ursächlich konnten dabei die empfohlenen Werte für die rechnerische Ermittlung der Mantelreibung identifiziert werden. Dies wurde vom Arbeitskreis zum Anlass genommen, die aktuellen Empfehlungen detailliert zu überprüfen und unter Einbeziehung wissenschaftlicher Erkenntnisse und praktischer Erfahrungen eine Überarbeitung vorzunehmen. Gegenstand des vorliegenden Aufsatzes ist die Begründung des Erfordernisses der Anpassungen, die inhaltliche Begründung der vorgenommenen Überarbeitungen und der Abdruck des Entwurfs der überarbeiteten Empfehlungen mit der Bitte um Stellungnahme durch die Fachwelt.
Stability‐indicating spectrofluorimetric method for the assay of riboflavin and photoproducts: Kinetic applications
Authors: Ahmad Iqbal , Anwar Zubair , Sheraz Muhammad Ali , Ahmed Sofia , Khattak Saif‐ur‐Rehman 
Published: July 2018

AbstractA stability‐indicating spectrofluorimetric method has been developed for the simultaneous assay of riboflavin (RF) and photoproducts, formylmethylflavin (FMF), lumichrome (LC) and lumiflavin (LF) in aqueous solution. The method is based on the extraction of LC formed in acid solution and LC and LF formed in alkaline solution with chloroform at pH 2.0 and their assay by fluorescence measurements at 478 and 530 nm, respectively. The aqueous phase, on readjustment of the pH to 6.5, is used to extract FMF with chloroform and its assay is carried out at 530 nm. The aqueous phase is then used for the assay of RF at 530 nm. The proposed method gives more accurate results for the assay of RF compared to those of the United States Pharmacopeia (USP) spectrofluorimetric method which does not take into account the presence of RF photoproducts having similar fluorescence characteristics. The proposed method along with the USP method has been applied to the study of the kinetics of photolysis of RF, assay of stored commercial vitamin preparations and their radiated samples. The results show that the USP method does not distinguish between the fluorescence of RF and its photoproducts, and, therefore, gives erroneous results with about 11% excess in the quantity of the vitamin compared to that of the proposed method. This is due to the interference of the fluorescence of photoproducts in the assay of RF. The method has been validated for various analytical parameters according to the guideline of the International Council for Harmonization (ICH).
Learning analytics on graduates’ academic records to reflect on a competency‐based curriculum
Authors: Chou Chih‐Yueh , Tseng Shu‐Fen , Wang Cheng‐Jhang , Chao Po‐Yao , Chen Zhi‐Hong , Lai K. Robert , Chan Chien‐Lung , Yu Liang‐Chih 
Published: July 2018

AbstractA competency‐based curriculum involves an outcome‐based approach for cultivating graduates’ core competencies required for specific professions. A curriculum committee defines graduates’ outcomes of core competencies, designs a curriculum to cultivate core competencies, evaluates graduates’ outcomes, and reflects on and regulates the curriculum. However, curriculum committees lack systematic evaluative information for reflection. Learning analytics, an emerging data‐driven analytics of educational data, could be applied to assist curriculum committees in reflection. This study proposes competency‐based learning analytics, including seven analytic tools, to analyze curricula and graduates’ academic records to assist curriculum committees in reflecting (1) objectives, competencies, and curriculum design of competency‐based curricula and (2) faculty teaching and student learning. The proposed learning analytics were conducted on 14 departments of a university. This study reports the curriculum committees’ eight practical reflections of curricula, faculty teaching, and student learning. This study illustrates potential applications and impact of competency‐based learning analytics on competency‐based curricula.
Flexible Assembly of an Enzyme Cascade on a DNA Triangle Prism Nanostructure for the Controlled Biomimetic Generation of Nitric Oxide
Authors: Zhou Li , Liu Yu , Shi Hui , Yang Xiaohai , Huang Jin , Liu Songyang , Chen Qiaoshu , Liu Jianbo , Wang Kemin 
Published: July 2018

AbstractSpatial organization of multiple enzymes at specific positions for a controlled reaction cascade has attracted wide attention in recent years. Here, we report the construction of a biomimetic enzyme cascade organized on DNA triangle prism (TP) nanostructures to enable the efficient catalytic production of nitric oxide (NO) on a single microbead. Two enzymes, glucose oxidase (GOx) and horseradish peroxidase (HRP), were assembled at adjacent locations on a DNA TP nanostructure by using DNA‐binding protein adaptors with small interenzyme distances. In the cascade, the first enzyme, GOx, converts glucose into gluconic acid in the presence of oxygen. The produced H2O2 intermediate is rapidly transported to the second enzyme, HRP, which oxides hydroxyurea into NO and other nitroxyl species. The pH near the surface of the negatively charged DNA nanostructures is believed to be lower than that in the bulk solution; this creates an optimal pH environment for the anchored enzymes, which results in higher yields of the NO product. Furthermore, the multienzyme system was immobilized on a microbead mediated by a DNA adaptor, and this enabled the efficient catalytic generation of gas molecules in the microreactor. Therefore, this work provides an alternative route for the biomimetic generation of NO through enzyme cascades. In particular, the dynamic binding capability of the DNA sequence enabled the positions of the protein enzyme and the DNA nanostructure to be reversed, which allowed the cascade catalysis to be modulated.
Transforming growth factor‐β1 increases C‐C chemokine ligand 11 production in interleukin 4‐stimulated human periodontal ligament cells
Authors: Hosokawa Yoshitaka , Hosokawa Ikuko , Ozaki Kazumi , Matsuo Takashi 
Published: July 2018

AbstractTransforming growth factor (TGF)‐β1 is a multifunctional cytokine, which can control certain functions of various kinds of cells. However, it is unclear whether TGF‐β1 affects T‐cell migration in periodontal lesions. The aim of this study was to examine the effects of TGF‐β1 on the production of C‐C chemokine ligand (CCL)11, which is a T‐helper 2‐type chemokine, in human periodontal ligament cells (HPDLC). Interleukin (IL)‐4 induced CCL11 production, but TGF‐β1 did not, in HPDLC. However, TGF‐β1 enhanced CCL11 production in IL‐4‐stimulated HPDLC. Western blot analysis showed that the signal transducer and activator of transcription 6 (STAT6) pathway was highly activated in HPDLC that had been stimulated with both IL‐4 and TGF‐β1. Mitogen‐activated protein kinase activation did not differ between the HPDLC treated with a combination of IL‐4 and TGF‐β1 and those treated with IL‐4 or TGF‐β1 alone. Moreover, a STAT6 inhibitor significantly inhibited CCL11 production in HPDLC that had been stimulated with IL‐4 and TGF‐β1. The current study clearly demonstrated that TGF‐β1 enhanced IL‐4‐induced CCL11 production in HPDLC. The STAT6 pathway is important for CCL11 production in IL‐4‐ and TGF‐β1‐treated HPDLC.
Chemical Conversion of Steel Mill Gases to Urea: An Analysis of Plant Capacity
Authors: Yildirim Ömer , Nölker Klaus , Büker Karsten , Kleinschmidt Ralph 
Published: July 2018

AbstractA significant amount of global carbon dioxide emissions is due to steel mill gases. One promising approach for the reduction of these emissions is their chemical conversion. In this regard, the conversion to urea is very advantageous, since common urea processes are already using carbon dioxide as a feedstock. In the present paper, urea capacities are determined that can be realized using steel mill gases. The capacities are estimated based on new process concepts that are presented in this paper. Exemplarily, the steel mill of thyssenkrupp Steel in Duisburg, Germany, is considered. It could be shown that reasonable urea capacities can be reached. By this means, a great impact can be made on the reduction of steel mill carbon dioxide emissions.
Recent Developments in the Conversion of Synthesis Gas to Short‐Chain Alcohols over Cu‐Co‐Based Catalysts
Authors: Schmidt Stefan , Göbel Christoph , Nebel Janine , Wiesmann Thomas , Hamel Christian , Reinsdorf Arne , Wolf Dorit , Gehrmann Stefan , Tenhumberg Nils , Muhler Martin , Kaluza Stefan 
Published: July 2018

AbstractCu‐Co‐based catalysts provide promising systems for higher alcohol synthesis (HAS) due to a synergistic dual‐site mechanism. Bimetallic Cu‐Co (alloy) nanoparticles are assumed to be the active sites, but cobalt carbide (Co2C) forming under reaction conditions also seems to influence the formation of C2+OH. Na‐doped Co‐modified Cu/ZnO/Al2O3 is applied as benchmark catalyst within the Carbon2Chem® subproject L4 providing suitable performance in terms of CO conversion and C2+OH selectivity. However, further optimization is required in order to develop an economically viable HAS process.
X‐ray Structures and Feasibility Assessment of CLK2 Inhibitors for Phelan–McDermid Syndrome
Authors: Kallen Joerg , Bergsdorf Christian , Arnaud Bertrand , Bernhard Mario , Brichet Murielle , Cobos‐Correa Amanda , Elhajouji Azeddine , Freuler Felix , Galimberti Ivan , Guibourdenche Christel , Haenni Simon , Holzinger Sandra , Hunziker Juerg , Izaac Aude , Kaufmann Markus , Leder Lukas , Martus Hans‐Joerg , von Matt Peter , Polyakov Valery , Roethlisberger Patrik , Roma Guglielmo , Stiefl Nikolaus , Uteng Marianne , Lerchner Andreas 
Published: July 2018

AbstractCLK2 inhibition has been proposed as a potential mechanism to improve autism and neuronal functions in Phelan–McDermid syndrome (PMDS). Herein, the discovery of a very potent indazole CLK inhibitor series and the CLK2 X‐ray structure of the most potent analogue are reported. This new indazole series was identified through a biochemical CLK2 Caliper assay screen with 30k compounds selected by an in silico approach. Novel high‐resolution X‐ray structures of all CLKs, including the first CLK4 X‐ray structure, bound to known CLK2 inhibitor tool compounds (e.g., TG003, CX‐4945), are also shown and yield insight into inhibitor selectivity in the CLK family. The efficacy of the new CLK2 inhibitors from the indazole series was demonstrated in the mouse brain slice assay, and potential safety concerns were investigated. Genotoxicity findings in the human lymphocyte micronucleus test (MNT) assay are shown by using two structurally different CLK inhibitors to reveal a major concern for pan‐CLK inhibition in PMDS.
Rectal cancer patients younger than 50 years lack a survival benefit from NCCN guideline–directed treatment for stage II and III disease
Authors: Kolarich Andrew , George Thomas J. , Hughes Steven J. , Delitto Daniel , Allegra Carmen J. , Hall William A. , Chang George J. , Tan Sanda A. , Shaw Christiana M. , Iqbal Atif 
Published: July 2018

BACKGROUNDThe incidence of rectal cancer in patients younger than 50 years is increasing. To test the hypothesis that the biology in this younger cohort may differ, this study compared survival patterns, stratifying patients according to National Comprehensive Cancer Network (NCCN) guideline–driven care and age.METHODSThe National Cancer Data Base was queried for patients treated with curative‐intent transabdominal resections with negative surgical margins for stage I to III rectal cancer between 2004 and 2014. Outcomes and overall survival for patients younger than 50 years and patients 50 years old or older were compared by subgroups based on NCCN guideline–driven care.RESULTSA total of 43,106 patients were analyzed. Younger patients were more likely to be female and minorities, to be diagnosed at a higher stage, and to have travelled further to be treated at academic/integrated centers. Short‐ and long‐term outcomes were significantly better for patients younger than 50 years, with age‐specific survival rates calculated. Younger patients were more likely to receive radiation treatment outside NCCN guidelines for stage I disease. In younger patients, the administration of neoadjuvant chemoradiation for stage II and III disease was not associated with an overall survival benefit.CONCLUSIONSAge‐specific survival data for patients with rectal cancer treated with curative intent do not support an overall survival benefit from NCCN guideline–driven therapy for stage II and III patients younger than 50 years. These data suggest that early‐onset disease may differ biologically and in its response to multimodality therapy.
Thickness‐Dependent Strain Evolution of Epitaxial SrTiO3 Thin Films Grown by Ion Beam Sputter Deposition
Authors: Panomsuwan Gasidit , Saito Nagahiro 
Published: July 2018

AbstractEpitaxial SrTiO3 (STO) thin films are grown on vicinal (001)‐oriented LaAlO3 (LAO) substrates with various thicknesses (3–108 nm) by an ion beam sputter deposition (IBSD). Thickness‐dependent strain in the STO films is investigated comprehensively through the X‐ray analysis. The STO films grow on the LAO substrates under a compressive strain along in‐plane direction (a‐ and b‐axes) and a tensile strain along the growth direction (c‐axis). With increasing film thickness, the STO unit cells evolve from more to less tetragonal structure, indicating the occurrence of strain relaxation. Quantitative strain analysis is also carried out for all STO films in terms of biaxial and hydrostatic components. It is found that the major cause of strain in STO films is caused by biaxial component over hydrostatic component. The surface morphology of STO films exhibit a step‐and‐terrace structure with roughness close to the LAO substrate (approx. 0.1 nm), indicating a 2D growth mode. However, as the film thickness increases, the surface terrace become rougher, which is caused by the effect of strain relaxation.
Local real‐time forecasting of ozone exposure using temperature data
Authors: Lu Xinyi , Gelfand Alan E. , Holland David M. 
Published: July 2018

AbstractRigorous and rapid assessment of ambient ozone exposure is important for informing the public about ozone levels that may lead to adverse health effects. In this paper, we use hierarchical modeling to enable real‐time forecasting of 8‐hr average ozone exposure. This contrasts with customary retrospective analysis of exposure data. Specifically, our contribution is to show how incorporating temperature data in addition to the observed ozone can significantly improve forecast accuracy, as measured by predictive performance and empirical coverage. We adopt two‐stage autoregressive models, also introducing periodicity and heterogeneity while still maintaining our objective of forecasting in real time. The entire effort is illustrated through modeling data collected at the Village Green monitoring station in Durham, North Carolina.