bluuebunny/crossref_metadata_2025 huggingface dataset:
Carbon‐Doped BN Nanosheets for the Oxidative Dehydrogenation of Ethylbenzene
Authors: Guo Fangsong , Yang Pengju , Pan Zhiming , Cao Xu‐Ning , Xie Zailai , Wang Xinchen
Published: May 2017

Carbon‐based catalysts have demonstrated great potential for the aerobic oxidative dehydrogenation reaction (ODH). However, its widespread application is retarded by the unavoidable deactivation owing to the appearance of coking or combustion under ODH conditions. The synthesis and characterization of porous structure of BCN nanosheets as well as their application as a novel catalyst for ODH is reported. Such BCN nanosheets consist of hybridized, randomly distributed domains of h‐BN and C phases, where C, B, and N were confirmed to covalent bond in the graphene‐like layers. Our studies reveal that BCN exhibits both high activity and selectivity in oxidative dehydrogenation of ethylbenzene to styrene, as well as excellent oxidation resistance. The discovery of such a simple chemical process to synthesize highly active BCN allows the possibility of carbocatalysis to be explored.
Der schmale Pfad tief in die Vergangenheit: auf der Suche nach der Chemie der Anfänge des Lebens
Authors: Szostak Jack W.
Published: May 2017

Die Abfolge der Ereignisse, durch die das erste Leben auf unserem Planeten entstand, vollzog sich in der tiefen Vergangenheit der Erde – für uns scheinbar gänzlich unerreichbar. Vielleicht ist gerade aus diesem Grund das Rekonstruieren unserer Urgeschichte eine verlockende, fast unwiderstehliche Vorstellung. Nachzuvollziehen, welche Vorgänge zur Synthese der chemischen Bausteine in der Biologie führten und wie sich diese Moleküle zu Zellen anordneten, die, durch eine reichhaltige und komplexe Umgebung gefördert, wachsen, sich teilen und entwickeln konnten, scheint derzeit mit unüberwindlichen Schwierigkeiten konfrontiert zu sein. Dennoch haben – zu meiner eigenen Überraschung – einfache Versuche stabile Prozesse offenbart, die das Wachstum und die Teilung primitiver Zellmembranen gesteuert haben könnten. Die nichtenzymatische Replikation von RNA ist komplizierter und weniger gut verstanden, aber auch hier haben überraschende Entwicklungen zu wichtigen Fortschritten geführt. Auch unsere Bemühungen, replizierende Kompartimente und genetisches Material zum vollständigen Modell einer Protozelle zu vereinen, sind auf unerwartete Weise vorangekommen. Glücklicherweise bleiben noch viele Herausforderungen, bevor wir uns einem umfassenden Verständnis der Anfänge des Lebens nähern, sodass die Zukunft dieses Forschungsgebiets aussichtsreicher ist als je zuvor!
Photoredox‐Controlled Mono‐ and Di‐Multifluoroarylation of C(sp3)−H Bonds with Aryl Fluorides
Authors: Xie Jin , Rudolph Matthias , Rominger Frank , Hashmi A. Stephen K.
Published: May 2017

A controllable mono‐ and di‐multifluoroarylation of acyclic and cyclic N‐aryl amines with aryl fluorides by photocatalyzed dual C(sp3)−H/C(sp2)−F functionalization has been developed, providing new access to a wide array of valuable α‐fluoroarylated amines. In addition, the one‐pot consecutive hetero‐di‐multifluoroarylation of N‐aryl pyrrolidines and N,N‐dimethylanilines was achieved with high to excellent diastereoselectivity. This new defluorinative C(sp3)−C(sp2) coupling is distinguished by a broad scope, good regioselectivity, and mild conditions as well as gram‐scale and late‐stage applicability, and thus constitutes a significant advance in the arylation of unactivated C(sp3)−H bonds with aryl fluorides.
Glycan Fingerprinting via Cold‐Ion Infrared Spectroscopy
Authors: Mucha Eike , González Flórez Ana Isabel , Marianski Mateusz , Thomas Daniel A. , Hoffmann Waldemar , Struwe Weston B. , Hahm Heung S. , Gewinner Sandy , Schöllkopf Wieland , Seeberger Peter H. , von Helden Gert , Pagel Kevin
Published: May 2017

The diversity of stereochemical isomers present in glycans and glycoconjugates poses a formidable challenge for comprehensive structural analysis. Typically, sophisticated mass spectrometry (MS)‐based techniques are used in combination with chromatography or ion‐mobility separation. However, coexisting structurally similar isomers often render an unambiguous identification impossible. Other powerful techniques such as gas‐phase infrared (IR) spectroscopy have been limited to smaller glycans, since conformational flexibility and thermal activation during the measurement result in poor spectral resolution. This limitation can be overcome by using cold‐ion spectroscopy. The vibrational fingerprints of cold oligosaccharide ions exhibit a wealth of well‐resolved absorption features that are diagnostic for minute structural variations. The unprecedented resolution of cold‐ion spectroscopy coupled with tandem MS may render this the key technology to unravel complex glycomes.
Δ‐Myrtoxin‐Mp1a is a Helical Heterodimer from the Venom of the Jack Jumper Ant that has Antimicrobial, Membrane‐Disrupting, and Nociceptive Activities
Authors: Dekan Zoltan , Headey Stephen J. , Scanlon Martin , Baldo Brian A. , Lee Tzong‐Hsien , Aguilar Marie‐Isabel , Deuis Jennifer R. , Vetter Irina , Elliott Alysha G. , Amado Maite , Cooper Matthew A. , Alewood Dianne , Alewood Paul F.
Published: May 2017

Δ‐Myrtoxin‐Mp1a (Mp1a), a 49‐residue heterodimeric peptide from the venom of Myrmecia pilosula, comprises a 26‐mer A chain and a 23‐mer B chain connected by two disulfide bonds in an antiparallel arrangement. Combination of the individual synthetic chains through aerial oxidation remarkably resulted in the self‐assembly of Mp1a as a homogenous product without the need for directed disulfide‐bond formation. NMR analysis revealed a well‐defined, unique structure containing an antiparallel α‐helix pair. Dual polarization interferometry (DPI) analysis showed strong interaction with supported lipid bilayers and insertion within the bilayers. Mp1a caused non‐specific Ca2+ influx in SH‐SY5Y cells with a half maximal effective concentration (EC50) of 4.3 μm. Mp1a also displayed broad‐spectrum antimicrobial activity, with the highest potency against Gram‐negative Acinetobacter baumannii (MIC 25 nm). Intraplantar injection (10 μm) in mice elicited spontaneous pain and mechanical allodynia. Single‐ and two‐chain mimetics of Mp1a revealed functional selectivity.
Overcoming the Instability of Nanoparticle‐Based Catalyst Films in Alkaline Electrolyzers by using Self‐Assembling and Self‐Healing Films
Authors: Barwe Stefan , Masa Justus , Andronescu Corina , Mei Bastian , Schuhmann Wolfgang , Ventosa Edgar
Published: May 2017

Engineering stable electrodes using highly active catalyst nanopowders for electrochemical water splitting remains a challenge. We report an innovative and general approach for attaining highly stable catalyst films with self‐healing capability based on the in situ self‐assembly of catalyst particles during electrolysis. The catalyst particles are added to the electrolyte forming a suspension that is pumped through the electrolyzer. Particles with negatively charged surfaces stick onto the anode, while particles with positively charged surfaces stick to the cathode. The self‐assembled catalyst films have self‐healing properties as long as sufficient catalyst particles are present in the electrolyte. The proof‐of‐concept was demonstrated in a non‐zero gap alkaline electrolyzer using NiFe‐LDH and NixB catalyst nanopowders for anode and cathode, respectively. Steady cell voltages were maintained for at least three weeks during continuous electrolysis at 50–100 mA cm−2.
The Narrow Road to the Deep Past: In Search of the Chemistry of the Origin of Life
Authors: Szostak Jack W.
Published: May 2017

The sequence of events that gave rise to the first life on our planet took place in the Earth's deep past, seemingly forever beyond our reach. Perhaps for that very reason the idea of reconstructing our ancient story is tantalizing, almost irresistible. Understanding the processes that led to synthesis of the chemical building blocks of biology and the ways in which these molecules self‐assembled into cells that could grow, divide and evolve, nurtured by a rich and complex environment, seems at times insurmountably difficult. And yet, to my own surprise, simple experiments have revealed robust processes that could have driven the growth and division of primitive cell membranes. The nonenzymatic replication of RNA is more complicated and less well understood, but here too significant progress has come from surprising developments. Even our efforts to combine replicating compartments and genetic materials into a full protocell model have moved forward in unexpected ways. Fortunately, many challenges remain before we will be close to a full understanding of the origin of life, so the future of research in this field is brighter than ever!
Effect of gypsum crystallization characteristics on fine particle emission after desulfurization
Authors: Pan Danping , Wu Hao , Yang Linjun
Published: May 2017

For the control of fine particle emission after desulfurization, the effect of gypsum crystallization characteristics during limestone‐gypsum wet flue gas desulfurization process was investigated. The results showed that crystals produced during the desulfurization process were mostly CaSO4 · 2H2O with uniform prismatic shape. An optimal temperature, lower pH value and the adoption of forced oxidation were beneficial to restrain the generation of fine crystals in the desulfurization slurry. Meanwhile, the optimization of the desulfurization environment was essential for the improvement of the gypsum crystal qualities. Furthermore, the fine particle concentrations after desulfurization were related to the gypsum crystallization characteristics in the slurry, which were decreased by 20%–30% with optimized slurry as the generation of fine crystals in the desulfurization slurry was inhibited. Hence, the optimization of gypsum crystallization characteristics in the slurry was a feasible method to reduce the fine particle emissions after desulfurization. © 2017 Curtin University of Technology and John Wiley & Sons, Ltd.
High‐density green polyethylene biocomposite reinforced with cellulose fibers and using lignin as antioxidant
Authors: Guilhen Augusto , Gadioli Renan , Fernandes Felipe C. , Waldman Walter R. , Aurelio De Paoli Marco
Published: May 2017

Aiming to manufacture biomaterials using renewable resources, we prepared, using a corotating and intermeshing twin‐screw extruder, high‐density green polyethylene composites reinforced with 20, 30, and 40 wt % of bleached cellulose fibers. Injection molded test samples are characterized for mechanical and thermal properties using thermogravimetry (TGA) and differential scanning calorimetry (DSC). These composites present improved mechanical properties relative to the pure matrix; the elastic modulus increases by 240% for the composite with 30 wt % of fiber. We characterize this composite, additionally formulated with lignin and a secondary antioxidant, by tensile and flexural mechanical properties, DSC, TGA, and oxidation induction time (OIT). Lignin has no effect on the mechanical properties; however, for the composite, the OIT increases from 24 to 77 min, clearly evidencing its effect as a stabilizer. Aging the composites for 1000 h, in a QUV chamber, confirms the stabilizing effect of lignin. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45219.
The massive formation of hybrid shish‐kebab structures in HDPE/PA6 microfibril blend subjected to melt second flow
Authors: Xie Dan‐Dan , Xia Xiao‐Chao , Huang Yan‐Hao , Chen Rui , Xie Bang‐Hu , Yang Ming‐Bo
Published: May 2017

During the melt second flow process, the synergetic effect of intense shear and polyamide 6 (PA6) microfibrils finally results in the massive formation of highly oriented crystalline structures in the entire thickness of high‐density polyethylene (HDPE)/PA6 microfibril blend. Interestingly, not only does the small microfibril induce HDPE crystallization to form typical hybrid shish–kebab structure, but the large microfibril (about 2 μm in diameter) also induces the formation of local hybrid shish–kebab structure. For the small PA6 microfibril, the oriented HDPE chains caused by the intense shear are absorbed on the whole surface of the microfibril and then a complete polymer underlayer is formed. Subsequently, the crystal nuclei appear on the underlayer, and then the other oriented HDPE chains overgrow from the nuclei in the form of folded chains and grow perpendicular to the microfibril. Finally, the typical hybrid shish–kebab structure is formed. While for the large PA6 microfibril, a few HDPE chains can be still absorbed on the microfibril surface due to the high surface energy of PA6. However, the driving force is insufficient to absorb largely oriented HDPE chains to form complete hybrid shish but only local adsorption layer, so the local hybrid structure is formed. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45274.
Photoluminescent properties of novel design heteroleptic Zn(II) complexes
Authors: Vamja Atul C. , Surati Kiran R.
Published: May 2017

Three novel heteroleptic Zn(II) complexes containing 8‐hydroxy quinoline and various pyrazolone‐based derivatives were synthesized and their structures confirmed by 1H–nuclear magnetic resonance, mass spectrometry, Fourier transform infra‐red spectroscopy, UV–vis analysis and element analysis. All three complexes showed good photoluminescence properties in the solid state and in solution in the maximum emission range from 475 to 490 nm with a quantum yield of 0.45 to 0.51. Absorption spectra revealed that the complexes possessed a maximum absorption range of 272–281 nm with a band gap of 2.59–2.68 eV. The highest occupied molecular orbital and lowest unoccupied molecular orbital of all the complexes were determine by cyclic voltammetry. All complexes displayed high thermal stability. These characteristics were assessed to find suitability for an alternative cheap light emitter for organic light‐emitting diodes.
Tuneable luminescence properties of EDTA‐assisted ZnS:Mn nanocrystals from a yellow‐orange to a red emission band
Authors: Viswanath R. , Bhojya Naik H. S. , Arun Kumar G. , Suresh Gowda I. K. , Yallappa S.
Published: May 2017

Luminescence technology has been improved with the help of semiconductor nanoparticles that possess novel optical and electrical properties compared with their bulk counterpart. The aim of this study was to design semiconductor nanocrystals in their pure (ZnS) or doped form (ZnS:Mn) with different concentrations of Mn2+ ions by a wet chemical route stabilized by ethylenediamine tetra‐acetic acid (EDTA) and to evaluate their luminescence properties. The nanocrystals were characterized by physicochemical techniques such as X‐ray diffraction (XRD), High‐resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SEAD), EDS, and ultraviolet (UV)–visible light and photoluminescence (PL) studies. These results showed the presence of cubic phase and spherically shaped nanocrystals. A blue shift with respect to their bulk counterpart was observed. PL emission spectra were observed with a fixed blue peak and the yellow‐orange bands were red shifted towards the red region under the same excitation wavelength. The orange‐red bands were attributed to the radiation transition of electrons in 3d5 unfilled shells of Mn2+ ions [4T1(4G)‐6A1(6S)]; the ZnS matrix varied with Mn2+ concentration. Shift and increase in the intensity of the PL and absorption bands were observed with increase in Mn content. The study showed that Mn2+‐doped ZnS nanocrystal emission bands can be tuned from the yellow‐orange to the red regions under a controlled synthesis process and could be used as promising luminescent emitters in the biology field upon functionalization with suitable materials. Further studies on construction with various other materials will be useful for practical applications.
Novel enantioselective fluorescent sensors for tartrate anion based on acridinezswsxa
Authors: Wang Chaoyu , Wang Peng , Liu Xiaoyan , Fu Jiaxin , Xue Kun , Xu Kuoxi
Published: May 2017

Novel chiral fluorescence sensors L‐1 and D‐1 incorporating N‐Boc‐protected alanine and acridine moieties were synthesized. The recognition ability of the sensors was studied by fluorescence titration, 1H NMR spectroscopy and density functional theory (DFT) calculations. The sensors exhibited good enantioselective fluorescent sensing ability toward enantiomers of tartrate anion for the selected carboxylate anions and formed 1: 1 complexes by multiple hydrogen bonding interactions.
Universal label‐free in‐process quantification of influenza virus‐like particles
Authors: Carvalho Sofia B. , Moleirinho Mafalda G. , Wheatley David , Welsh John , Gantier René , Alves Paula M. , Peixoto Cristina , Carrondo Manuel J. T.
Published: May 2017

Virus‐like particles (VLPs) are becoming established as vaccines, in particular for influenza pandemics, increasing the interest in the development of VLPs manufacturing bioprocess. However, for complex VLPs, the analytical tools used for quantification are not yet able to keep up with the bioprocess progress. Currently, quantification for Influenza relies on traditional methods: hemagglutination assay or Single Radial Immunodiffusion. These analytical technologies are time‐consuming, cumbersome, and not supportive of efficient downstream process development and monitoring. Hereby we report a label‐free tool that uses Biolayer interferometry (BLI) technology applied on an Octet platform to quantify Influenza VLPs at all stages of bioprocess. Human (α2,6‐linked sialic acid) and avian (α2,3‐linked sialic acid) biotinylated receptors associated with streptavidin biosensors were used, to quantify hemagglutinin content in several mono‐ and multivalent Influenza VLPs. The applied method was able to quantify hemagglutinin from crude samples up to final bioprocessing VLP product. BLI technology confirmed its value as a high throughput analytical tool with high sensitivity and improved detection limits compared to traditional methods. This simple and fast method allowed for real‐time results, which are crucial for in‐line monitoring of downstream processing, improving process development, control and optimization.
Injury to the infrapatellar branch of the saphenous nerve during tendon graft harvesting for knee ligament reconstruction: An ultrasound simulation study
Authors: Pękala Przemysław A. , Miza Ewa , Henry Brandon Michael , Popieluszko Patrick , Loukas Marios , Tomaszewski Krzysztof A.
Published: May 2017

The clinical anatomy of the infrapatellar branch of the saphenous nerve (IPBSN) is of particular importance during operations in the area of the knee, especially when material for anterior cruciate ligament reconstruction is harvested. The nerve can easily be injured during the harvesting procedure, leading to postoperative complications that reduce quality of life. Three different skin incisions are commonly used during hamstring tendon harvesting: horizontal, vertical, and oblique. The aim of this ultrasound simulation study was to assess the risk of IPBSN injury associated with the type of skin incision and the point‐of‐emergence of the IPBSN relative to the sartorius muscle. Thirty healthy volunteers (60 lower limbs) were recruited for identification of the IPBSN. When it was found, using a high‐frequency ultrasound probe, three different 3 cm skin incisions over the pes anserinus were simulated. Vertical, horizontal, or oblique lines simulating incisions were marked over the pes anserinus and ultrasound was used to visualize the structures that could be injured during the marked incisions. The IPBSN was visualized in 58 lower limbs (96.7%). The results of the simulation study indicated that the vertical incision should be avoided during hamstring tendon harvesting, as it is associated with a significantly higher risk of injury (25.9%) to the IPBSN than the horizontal (3.5%) or oblique (8.6%) incisions. We recommend that a preoperative ultrasound assessment of IPBSN anatomy be performed to minimize the risk of iatrogenic injury to the nerve and associated complications. Clin. Anat. 30:868–872, 2017. © 2017 Wiley Periodicals, Inc.
Brain ultrasound rehearsal before surgery: A pilot cadaver study
Authors: Giussani Carlo , Riva Matteo , Djonov Valentin , Beretta Simone , Prada Francesco , Sganzerla Erik
Published: May 2017

It has been shown that brain ultrasonography (US) is an efficient tool for improving three‐dimensional (3D) spatial orientation during neurosurgical interventions. However, it necessitates specific training as it is highly operator‐dependent. To date, neurosurgeons have relied solely on intraoperative practice to improve their mastery of brain US; this has obvious limitations. Herein, we consider whether a study of brain US on human cadavers could enable a training platform for neurosurgeons and residents to be developed. Standard two‐dimensional (2D) brain US was performed on two human cadavers (one fresh‐frozen and one Thiel‐prepared) through left frontoparietal, left frontal, right temporal, and left parietal craniotomies. US workflow and image quality were assessed in both preparations. It was possible to assess US in both cadaver preparations; however, the specimen prepared with Thiel‐fixation performed better, with superior image quality and specimen usability at room temperature. US images were obtainable through all surgical corridors with the main intracranial anatomical landmarks easily identifiable. US of cadaveric brains is feasible and delivers good quality results. This technique could allow neurosurgeons to develop the expertise required for a successful clinical application preoperatively. Clin. Anat. 30:1017–1023, 2017. © 2017 Wiley Periodicals, Inc.
Operationalizing procedural justice in university policing
Authors: Murauskas Aaron
Published: May 2017

To effectively operationalize procedural justice, we, as police administrators, must be the model. As police officers, we define ourselves as the “finest,” who swear under oath to perform to the best of our abilities. We confirm that our profession is one requiring noble effort that employs only those with the highest standards of integrity; yet we fall short in providing the communities that we serve a demonstration of the legitimacy of these ideas. By effectively operationalizing procedural justice and using it as a guide to establish policy, enable practices, and guide leadership, we can effect change that will allow for this demonstration.
Electrogenerated Chemiluminescence of Semiconductor Nanoparticles and Their Applications in Biosensors
Authors: Benoit Lora , Choi Jai‐Pil
Published: May 2017

Compared to fluorescence, electrogenerated chemiluminescence (ECL) can be a superior analytical tool in terms of sensitivity and signal‐to‐noise ratios, owing to the absence of background emissions from unwanted photoexcitation. Semiconductor nanoparticles (NPs) are highly promising in many analytical applications, because they can produce stable ECL and possess surface‐dependent, tunable ECL properties. This Minireview gives a brief overview of ECL energetics and processes, the current progress of ECL of semiconductor NPs, and recent advances in biological sensing based on ECL of semiconductor NPs. The current challenges and perspectives on ECL of semiconductor NPs and their biological sensing applications are also discussed.
Untersuchung alternativer Testszenarien zur Bestimmung der Biegezugfestigkeit von Dünnglas
Authors: Neugebauer Jürgen
Published: May 2017

Glas mit Dicken von 0,5 bis 2,0 mm kann als ein Dünnglas oder auch als ultraleicht definiert werden. Nicht nur der konstruktive Entwurf sowie die Bemessung von dünnem Glas verursacht eine völlig neue Art des Denkens, ebenso mögliche Testszenarien für die Bestimmung der maximalen Biegezugfestigkeit sind derzeit in Normen nicht ausreichend geregelt. Bestehenden Versuchsaufbauten, wie sie in einschlägigen Normen beschriebenen sind, wie z.B. der Vierschneiden‐Biegeversuch in EN 1288‐3 oder der große Doppelring‐Biegeversuch in EN 1288‐2, können zur Bestimmung der maximalen Biegezugfestigkeit von Dünnglas nicht herangezogen werden. Unterschiedliche alternative Versuchsaufbauten, publiziert in mehreren wissenschaftlichen Veröffentlichungen wurden hinsichtlich ihrer Anwendbarkeit zur Bestimmung der Biegezugfestigkeit untersucht und analysiert.
Photovoltaik‐Sanierung zur Vermeidung von sommerlicher Überhitzung
Authors: Moor Dieter
Published: May 2017

Sommerliche Überhitzung und Erneuerbare Energie sind zwei wesentliche Themen, die die Bauindustrie beschäftigt. In diesem Aufsatz sollen Fragen behandelt werden, wie diese beiden Herausforderungen mit Photovoltaik Sanierungssystemen gelöst werden können. Dabei wird auf die statische Bemessung eingegangen. Die Leitungsverlegung in den Profilen und Führung zu den Wechselrichtern wird betrachtet. Beurteilung des Isolierglasalters bzw. ab wann ist die Sinnhaftigkeit der Variante zu hinterfragen? Variantenvergleich: aufgesetztes System zu Isolierglastausch. Kosten bzw. Kostenvergleich einer Sanierungsvariante mit Aufsatzsystem mit einem Isolierglastausch. Reinigungsmöglichkeiten und Konflikte etwa einer über das Dach geführten Rauchentlüftung.
Vom Gebäude zur Medienfassade – LED‐Verkapselung durch Flüssiglaminierung
Authors: Scherer Christian , Davis Chris , Göke Knut , Semar Ernst , Wittwer Wolfgang
Published: May 2017

Die Gestaltung von Fassaden rückt immer stärker in den Fokus der modernen Medienkommunikation. G‐Glass wird gegenwärtig als eines der weltweit modernsten Medienfassadenprodukte betrachtet. Die erfolgreiche Laminierung und LED‐Verkapselung mit einem flüssigen Acrylverbundmaterial von Kömmerling ist dabei der Schlüssel zur Verwendung des Produktes als gebäudeintegriertes Bauteil. Die Integration dieser transparenten und tageslichtdurchlässigen Medien‐Fassaden in die Gebäudehülle bringen dabei spezielle Herausforderungen mit sich wie beispielsweise Langzeittemperaturbeständigkeit und UV‐Stabilität. Dieser Beitrag gibt einen Überblick über die passiven und aktiven Anwendungen von G‐Glass Produkten, beschreibt die Einkapselung von einfarbig weißen und bunten RGB (Rot Grün Blau; additiver Farbraum) LED‐Leuchtmitteln in Glaselemente und zeigt den Herstellungsprozess der UV‐härtenden Laminierung.
Gläserner Juwel über der Vorfahrt
Authors: Ruch Andreas , Roffler Corsin , Estermann Ronny
Published: May 2017

Nach rund vierjähriger Bauzeit wurde im Dezember 2013 das 5‐Stern‐Superior‐Hotel “The Chedi” in Andermatt (CH) eröffnet. Zwischenzeitlich hat das erste Hotel des neuen Resorts mehrere schneereiche Winter hinter sich und wurde somit einer harten Prüfung unterzogen. Der Beitrag be‐richtet über die komplett aus Glas gebaute Überdachung der Hotelvorfahrt und wie dieser “gläserne Juwel” den standortbedingten Wetterbedingungen standhält.
Qualitativ hochwertige Rand‐Emaillierung für Architekturglas
Authors: Greiner Ralf
Published: May 2017

Das Guardian‐System TEA wurde in Kooperation mit der Firma Ferro entwickelt. Es beinhaltet spezielle keramische Farben für die Anwendung mit Guardian sputter‐beschichtetem Architekturglas. Mit dieser Technologie können äußerst stabile und homogene keramische Oberflächen erzeugt werden. Damit ausgestattete Gläser sind ideal zum Beispiel für strukturelle Verklebungen, Ganzglasecken, überstehende Dachverglasungen oder Lamellenfenster geeignet. Die materialauflösende Keramikfarbe (Emaille) wird direkt auf die Sputter‐Beschichtung aufgetragen und löst diese während der Wärmebehandlung auf. Die Emaille verschmilzt mit dem Glas und sorgt für eine außergewöhnlich starke Verbindung. Nach dem Abkühlen ist das Beschichtungsmaterial vollständig in die Emaille eingebettet.
Role of Halide Ions in the Nature of the Magnetic Anisotropy in Tetrahedral CoII Complexes
Authors: Vaidya Shefali , Singh Saurabh Kumar , Shukla Pragya , Ansari Kamaluddin , Rajaraman Gopalan , Shanmugam Maheswaran
Published: May 2017

A series of mononuclear tetrahedral CoII complexes with a general molecular formula [CoL2X2] [L=thiourea and X=Cl (1), Br (2) and I (3)] were synthesized and their structures were characterized by single‐crystal X‐ray diffraction. Direct‐current (dc) magnetic susceptibility [χMT(T) and M(H)] and its slow relaxation of magnetization were measured for all three complexes. The experimental dc magnetic data are excellently reproduced by fitting both χMT(T) and M(H) simultaneously with the parameters D=+10.8 cm−1, g1=2.2, g2=2.2, and g3=2.4 for 1; D=−18.7 cm−1, giso=2.21 for 2; and D=−19.3 cm−1, giso=2.3 for 3. The replacement of chloride in 1 by bromide or iodide (in 2 and 3, respectively) was accompanied by a change in both sign and magnitude of the magnetic anisotropy D. Field‐induced out‐of‐phase susceptibility signals observed in 10 % diluted samples of 1–3 imply slow relaxation of magnetization of molecular origin. To better understand the magnetization relaxation dynamics of complexes 1–3, detailed ab initio CASSCF/NEVPT2 calculations were performed. The computed spin Hamiltonian parameters are in good agreement with experimental data. In particular, the calculations unveil the role of halide ions in switching the sign of D on moving from Cl− to I−. The large spin–orbit coupling constant associated with the heavier halide ion and weaker π donation reduces the ground state–excited state gap, which leads to a larger contribution to negative D for complex 3 compared to complex 1. Further magnetostructural D correlations were developed to understand the role of structural distortion in the sign and magnitude of D values in this family of complexes.
Fluorinated Porous Conjugated Polyporphyrins through Direct C−H Arylation Polycondensation: Preparation, Porosity, and Use as Heterogeneous Catalysts for Baeyer–Villiger Oxidation
Authors: Cao Qiang , Yin Qing , Chen Qi , Dong Zhi‐Bing , Han Bao‐Hang
Published: May 2017

By considering the high reactivity of fluorinated iron–porphyrin and good stability of porphyrin‐based porous polymers, fluorinated iron–porphyrin conjugated porous polymers (FPOP‐3–6) were synthesized through direct C−H arylation polymerization. The obtained materials are chemically and thermally stable, of which FPOP‐3 exhibits the highest Brunauer–Emmett–Teller specific surface area (about 840 m2 g−1). For functional studies of the obtained polymers as heterogeneous catalysts, catalytic transformation of cycloketones into lactones by oxygen through Baeyer–Villiger oxidation was used as a model reaction. Fluorinated phenyl substituents of the iron–porphyrin not only are beneficial to the conversion, but also can stabilize the porphyrin to resist catalyst breakdown. The polymer FPOP‐3, with high porosity, exhibits the best catalytic efficiency and recycling effect. The recovered catalyst also shows good catalytic activities after recycling three times with a small loss in yield.
Nitramino‐ and Dinitromethyl‐Substituted 1,2,4‐Triazole Derivatives as High‐Performance Energetic Materials
Authors: Tang Yongxing , Dharavath Srinivas , Imler Gregory H. , Parrish Damon A. , Shreeve Jean'ne M.
Published: May 2017

Since highly nitrated nitrogen‐rich heterocycles are important motifs in high energy density materials, extensive studies for the development of such novel molecules have been underway. A highly energetic moiety, 3‐dinitromethyl‐5‐nitramino‐1,2,4‐triazole, which consists of a triazole ring, and nitramino and dinitromethyl groups, has been designed and synthesized. By pairing with nitrogen‐rich cations, several ionic derivatives were obtained. Theoretical and experimental studies show that the hydroxylammonium salt (7) is highly dense, and has excellent detonation performance with acceptable thermal stablity and sensitivities, which are superior to those of RDX.
Competition versus Cooperation in Catalytic Hydrogelators for anti‐Selective Mannich Reaction
Authors: Singh Nishant , Escuder Beatriu
Published: May 2017

Chemical systems find similarities in different sociological and biological processes, in which the entities compete or cooperate for a favorable outcome. The structural and functional adaptations leading to emergent properties, especially in catalysis, are based on factors such as abundance of substrates, stability of the transition state, and structural/functional attributes of catalysts. Proline and acid groups appended to catalytic fibers of two self‐sorting hydrogelators compete for the Mannich reaction between aniline, benzaldehyde, and cyclohexanone to give low overall selectivity (anti/syn 77:23). In a sol–gel system of the same molecules, on the other hand, the soluble acid appended molecules tend to cooperate with the fibers of proline‐appended catalyst to give improved selectivity (anti/syn 95:5). The available options for the catalytic molecules are to carry out the reaction independently or in cooperation. However, these options are chosen based on the efficiency, selectivity, and mobility of catalysts as a result of their abilities to self‐assemble.
Unraveling the Coulombic Forces in Electronically Decoupled Bichromophoric Systems during Two Successive Electron Transfers
Authors: Ivanov Maxim V. , Wadumethrige Shriya H. , Wang Denan , Rathore Rajendra
Published: May 2017

Coulombic forces are vital in modulating the electron transfer dynamics in both synthetic and biological polychromophoric assemblies, yet quantitative studies of the impact of such forces are rare, as it is difficult to disentangle electrostatic forces from simple electronic coupling. To address this problem, the impact of Coulombic interactions in the successive removal of two electrons from a model set of spirobifluorenes, where the interchromophoric electronic coupling is nonexistent, is quantitatively assessed. By systematically varying the separation of the bifluorene moieties using model compounds, ion pairing, and solvation, these interactions, with energies up to about 0.4 V, are absent at distances greater than about 9 Å. These findings can be (quantitatively) applied for the design of polychromophoric assemblies, whereby the redox properties of donors and/or acceptors can be tuned by judicious positioning of the charged groups to control the electron‐transfer dynamics.
Development of helical coil based fluidic diode pump for liquid pumping
Authors: Manavalan Balamurugan , Pandey Niranjan K. , Kumar Shekhar , Mudali Kamachi U. , Joshi Jyeshtharaj B.
Published: May 2017

The main selection criterion for pumps in reprocessing applications is the absence of any moving parts or the moving parts not having any direct contact with the process fluid. There are different types of fluidic pumps such as vortex diode, reverse flow diode, etc. In this work, a new design of helical coil fluidic pump has been developed and demonstrated. Helical coils are widely used in process industries as heat exchangers, reactors, motionless mixers, etc. It is for the first time that the authors are proposing the use of helical coil as a fluidic pump based on its inherent property of high pressure drop as compared to a straight tube.

The main objective of this work is to develop an alternate pumping system for reprocessing applications to replace the conventional air lift pump. The helical coil based fluidic diode pump was made up of SS 304 seamless pipe (pipe inner diameter is 9.5 mm) with a 36 mm diameter of helical coil and pitch of 14 mm. In this work, friction factor for the given helical coil was measured from pressure drop experiments. This information was also useful for understanding the transition of the laminar to turbulent region. In order to propose the operating region, the pumping capacity was measured for the helical coil based fluidic pump at different operating conditions. Experimental results show that the proposed hardware is able to pump up to 54 dm3/h. Recommendations have been made for proposing an optimum design.
Heart rate and outcome in heart failure with reduced ejection fraction: Differences between atrial fibrillation and sinus rhythm—A CIBIS II analysis
Authors: Mulder Bart A. , Damman Kevin , Van Veldhuisen Dirk J. , Van Gelder Isabelle C. , Rienstra Michiel
Published: May 2017

Background

Heart rate has been associated with prognosis in patients with heart failure with reduced ejection fraction (HFREF) and sinus rhythm; whether this also holds true in patients with atrial fibrillation (AF) is unknown.

Hypothesis

To evaluate cardiac rhythm and baseline heart rate and the influence of outcome in patients with HFREF enrolled in the Cardiac Insufficiency Bisoprolol Study II.

Methods

In total, 2539 patients were stratified according to their baseline heart rhythm (AF or sinus rhythm) and into quartiles of heart rate (≤70 bpm, 71–78 bpm, 79–90 bpm, and >90 bpm). The primary outcome was all‐cause mortality. Mean follow‐up was 1.3 years.

Results

Mean age was 61 years, mean left ventricular ejection fraction was 28%, and 80% were male. A total of 521 (21%) patients had AF at baseline. The risk associated with all‐cause mortality for each 5 bpm increase in heart rate in patients with sinus rhythm (hazard ratio [HR]: 1.06, 95% confidence interval [CI]: 1.01‐1.11, P = 0.012) was significantly different from those with AF (HR: 1.00, 95% CI: 0.94‐1.07, P = 0.90, P for interaction = 0.041). The risk associated with higher heart rate in sinus rhythm was primarily attributable to excess risk in the highest quartile (HR: 1.64, 95% CI: 1.18–2.30, P = 0.003). Allocation to bisoprolol did not modify the interaction between heart rate, rhythm and outcome.

Conclusions

In HFREF patients with AF, a higher heart rate is not associated with increased event rates in contrast to HFREF patients with sinus rhythm.
Adjuvant radiotherapy improves overall survival in patients with resected gastric adenocarcinoma: A National Cancer Data Base analysis
Authors: Stumpf Priscilla K. , Amini Arya , Jones Bernard L. , Koshy Matthew , Sher David J. , Lieu Christopher H. , Schefter Tracey E. , Goodman Karyn A. , Rusthoven Chad G.
Published: May 2017

BACKGROUND

For patients with resectable gastric adenocarcinoma, perioperative chemotherapy and adjuvant chemoradiotherapy (CRT) are considered standard options. In the current study, the authors used the National Cancer Data Base to compare overall survival (OS) between these regimens.

METHODS

Patients who underwent gastrectomy for nonmetastatic gastric adenocarcinoma from 2004 through 2012 were divided into those treated with perioperative chemotherapy without RT versus those treated with adjuvant CRT. Survival was estimated and compared using univariate and multivariate models adjusted for patient and tumor characteristics, surgical margin status, and the number of lymph nodes examined. Subset analyses were performed for factors chosen a priori, and potential interactions between treatment and covariates were assessed.

RESULTS

A total of 3656 eligible patients were identified, 52% of whom underwent perioperative chemotherapy and 48% of whom received postoperative CRT. The median follow‐up was 47 months, and the median age of the patients was 62 years. Analysis of the entire cohort demonstrated improved OS with adjuvant RT on both univariate (median of 51 months vs 42 months; P = .013) and multivariate (hazard ratio, 0.874; 95% confidence interval, 0.790‐0.967 [P = .009]) analyses. Propensity score‐matched analysis also demonstrated improved OS with adjuvant RT (median of 49 months vs 39 months; P = .033). On subset analysis, a significant interaction was observed between the survival impact of adjuvant RT and surgical margins, with a greater benefit of RT noted among patients with surgical margin‐positive disease (hazard ratio with RT: 0.650 vs 0.952; P for interaction <.001).

CONCLUSIONS

In this National Cancer Data Base analysis, the use of adjuvant RT in addition to chemotherapy was associated with a significant OS advantage for patients with resected gastric cancer. The survival advantage observed with adjuvant CRT was most pronounced among patients with positive surgical margins. Cancer 2017;123:3402‐9. © 2017 American Cancer Society.
Association between mutations of critical pathway genes and survival outcomes according to the tumor location in colorectal cancer
Authors: Lee Dae‐Won , Han Sae‐Won , Cha Yongjun , Bae Jeong Mo , Kim Hwang‐Phill , Lyu Jaemyun , Han Hyojun , Kim Hyoki , Jang Hoon , Bang Duhee , Huh Iksoo , Park Taesung , Won Jae‐Kyung , Jeong Seung‐Yong , Park Kyu Joo , Kang Gyeong Hoon , Kim Tae‐You
Published: May 2017

BACKGROUND

Colorectal cancer (CRC) develops through the alteration of several critical pathways. This study was aimed at evaluating the influence of critical pathways on survival outcomes for patients with CRC.

METHODS

Targeted next‐generation sequencing of 40 genes included in the 5 critical pathways of CRC (WNT, P53, RTK‐RAS, phosphatidylinositol‐4,5‐bisphosphate 3‐kinase [PI3K], and transforming growth factor β [TGF‐β]) was performed for 516 patients with stage III or high‐risk stage II CRC treated with surgery followed by adjuvant fluoropyrimidine and oxaliplatin chemotherapy. The associations between critical pathway mutations and relapse‐free survival (RFS) and overall survival were analyzed. The associations were further analyzed according to the tumor location.

RESULTS

The mutation rates for the WNT, P53, RTK‐RAS, PI3K, and TGF‐β pathways were 84.5%, 69.0%, 60.7%, 30.0%, and 28.9%, respectively. A mutation in the PI3K pathway was associated with longer RFS (adjusted hazard ratio [HR], 0.59; 95% confidence interval [CI], 0.36‐0.99), whereas a mutation in the RTK‐RAS pathway was associated with shorter RFS (adjusted HR, 1.60; 95% CI, 1.01‐2.52). Proximal tumors showed a higher mutation rate than distal tumors, and the mutation profile was different according to the tumor location. The mutation rates of Kirsten rat sarcoma viral oncogene homolog (KRAS), phosphatidylinositol‐4,5‐bisphosphate 3‐kinase catalytic subunit α (PIK3CA), and B‐Raf proto‐oncogene serine/threonine kinase (BRAF) were higher in proximal tumors, and the mutation rates of adenomatous polyposis coli (APC), tumor protein 53 (TP53), and neuroblastoma RAS viral oncogene homolog (NRAS) were higher in distal tumors. The better RFS with the PI3K pathway mutation was significant only for proximal tumors, and the worse RFS with the RTK‐RAS pathway mutation was significant only for distal tumors.

CONCLUSIONS

A PI3K pathway mutation was associated with better RFS for CRC patients treated with adjuvant chemotherapy, and an RTK‐RAS pathway mutation was associated with worse RFS. The significance of the prognostic impact differed according to the tumor location. Cancer 2017;123:3513‐23. © 2017 American Cancer Society.
Self‐Assembly and Local Manipulation of Au‐Pyridyl Coordination Networks on Metal Surfaces
Authors: Song Yang , Wang Yuxu , Jin Qiao , Zhou Kun , Shi Ziliang , Liu Pei‐Nian , Ma Yu‐qiang
Published: May 2017

Using scanning tunnelling microscopy (STM), we demonstrate that Au‐pyridyl coordination can be used to assemble two‐dimensional coordination network structures on metal surfaces. The polymorphism of the coordination network structures can be manipulated at both the micro‐ and nanoscale. Using the same organic ligand, we assembled two distinct polymorphic network structures, which were assisted by threefold Au‐pyridyl coordination on Ag(111) with predeposited Au atoms (α‐network), and by twofold Au‐pyridyl coordination on Au(111) (β‐network), respectively. Specifically on the Au(111) surface, single‐oriented β‐network domains as large as ≈400 nm were selected by thermal annealing. We ascribe this global control strategy to distinct Au bonding modes tuned by molecule–substrate interactions. Using an STM tip, we succeeded in creating α‐network domains (≈10 nm) locally within the homogeneous β‐network domain areas on Au(111) in a controlled manner.
A Multiplexed, Gradient‐Based, Full‐Hydrogel Microfluidic Platform for Rapid, High‐Throughput Antimicrobial Susceptibility Testing
Authors: Liu Zhengzhi , Sun Han , Ren Kangning
Published: May 2017

Antimicrobial resistance has become an immediate threat to modern healthcare systems as it continues to spread across the globe. As development of novel antibiotics stalls, preserving the effectiveness of existing agents has become a priority. One of the major driving forces behind antimicrobial resistance is the misuse and overuse of antibiotics, often a result of data on the susceptibility of pathogens not being obtained in a convenient and timely manner, a need that conventional antimicrobial susceptibility testing struggles to meet. Here, a hydrogel microfluidic platform is reported for antimicrobial susceptibility testing purposes, capable of handling real samples and yielding results within 2.5 h of culture. By using a multiplayer design with channels crossing overhead of each other, multiple experiments, either one‐ or two‐dimensional, can be staged on the same device. Bacteria grown on the surface of the hydrogel can be easily visualized with standard Gram staining after being transferred onto a glass slide. Coupled with software‐based image analysis, the system can yield a variety of useful information on bacterial susceptibility and the effects of drugs, such as minimum inhibitory concentration and morphological changes in bacteria, either individually or in combination. Compared to conventional testing methods, this system requires less labor, reagents, and equipment to operate, and has significantly higher speed and efficiency.
Environmental variability indicates a climate‐adaptive center under threat in northern Mozambique coral reefs
Authors: McClanahan Timothy R. , Muthiga Nyawira A.
Published: May 2017

A priority for modern conservation is finding and managing regions with environmental and biodiversity portfolio characteristics that will promote adaptation and the persistence of species during times of rapid climate change. The latitudinal edges of high‐diversity biomes are likely to provide a mixture of environmental gradients and biological diversity that meet the portfolio criteria needed for adaptive systems. Northern Mozambique and the Quirimbas Islands represent the edge of a coral reef diversity center with limited potential to expand because of geologic and oceanographic limits on the southern edges. This region does, however, have the potential to be its own discrete adaptive center if it contains climate refugia and there are environmental gradients that promote acclimatization, ecological reorganization, and natural selection. Consequently, to evaluate this potential we tested for strong regional environmental spatial heterogeneity that might indicate a climate‐adaptive center. Additionally, we evaluated human influences and environmental and demographic data on finfish, coral, and sea urchins in 66 reefs across ~4° of latitude to evaluate ecological changes and human threats. A number of clear gradients in environmental and human influences were observed. For example, temperature increased and became more centralized and right‐skewed, while water quality decreased to the south. Coral communities susceptible to thermal stress were found in the north where dispersed temperatures indicated a location with either tolerance to or refugium from recent thermal disturbances. Nevertheless, high coral diversity was found in southern deep‐water channels. Further, spatial patterns for corals and fish differed indicating complex geographic‐fishing‐biodiversity gradients. Consequently, environmental conditions for an adaptive portfolio exist and include refugia for preserving climate‐sensitive and for numbers of coral taxa. Fishing and urban threats were observable as reduced fish biomass, diversity, and body sizes but higher biomass of sea urchins. We observed that many remote and protected areas had fish biomass values lower than expected or near maximum sustainable yields. This indicates low compliance and widespread migratory fishing, which is reducing fish diversity below maximum levels. Recommendations to sustain this adaptive center are to maintain fish biomass >500 kg/ha by increasing fisheries restrictions and compliance.
Synthesis and Electrocatalytic Activity of [FeFe]‐Hydrogenase Model Complexes with Non‐Innocent Chelating Nitrogen‐Donor Ligands
Authors: Roy Souvik , Laureanti Joseph A. , Groy Thomas L. , Jones Anne K.
Published: May 2017

Invited for the cover of this issue is the group of AnneàK. Jones from Arizona State University, Tempe, AZ, USA. The cover image shows four complexes designed to mimic the H‐cluster at which protons are reduced to hydrogen in [FeFe]‐hydrogenase; only two inflate balloons by evolving hydrogen.