bluuebunny/crossref_metadata_2025_split huggingface dataset:
Novel insights into the marine phase and river fidelity of anadromous twaite shad Alosa fallax in the UK and Ireland
Authors: Davies Peter , Britton Robert J. , Nunn Andrew D. , Dodd Jamie R. , Crundwell Charles , Velterop Randolph , Ó’Maoiléidigh Niall , O'Neill Ross , Sheehan Emma V. , Stamp Thomas , Bolland Jonathan D. 
Published: June 2020

Abstract

Most research on anadromous fishes has been invested in their freshwater life‐phases, resulting in a relatively sparse understanding of their spatial ecology during marine life‐phases. However, understanding the marine dispersal of anadromous fishes is essential to identify threats and to implement conservation measures that fully encompass their lifecycle.
The twaite shad Alosa fallax is an anadromous fish increasingly imperilled across its range due to pollution, harvesting, and impediments to freshwater migration, but little is known about its distribution and movements during its marine life‐phase. Here, the application of acoustic telemetry provided novel insights into the coastal dispersal of twaite shad in the UK and Ireland during 2018–2019, and the freshwater entry of individuals during the 2019 spawning season.
Of 73 twaite shad acoustic‐tagged during their upstream migration in the River Severn in May 2018, 58 emigrated from the river. Twelve were subsequently detected 200 km to the south‐west at the Taw–Torridge Estuary between July 2018 and April 2019, where estuarine movements up to 5.8 km inland occurred in summer, winter, and spring. One was subsequently detected in the Munster Blackwater Estuary (Ireland) and then in the River Severn, indicating a minimum movement distance of 950 km. Thirty‐four (59%) of the emigrating individuals from 2018 re‐entered fresh water in the rivers Severn (n = 33) and Wye (n = 2) in April and May 2019.
These results suggest year‐round use of estuarine and nearshore habitats by at least a subset of the twaite shad population during their marine phase, providing evidence of potential range overlap between populations that spawn in different areas in the UK and Ireland, which may be facilitated by substantial dispersal. The results also highlight the potential of telemetry for estimating freshwater and marine mortality, and the benefits of sharing detection data across networks.
Dauer des Druckaufbaus bei Luftdichtheitsprüfungen sehr dichter Gebäude
Authors: Zeller Joachim 
Published: June 2020

AbstractBei der Blower‐Door‐Messung üblicher Häuser wird der erforderliche Differenzdruck an der Gebäudehülle, anders als oft von Laien erwartet, fast sofort erreicht. Aber bei sehr dichten Gebäuden kann es Minuten dauern, bis sich der Differenzdruck praktisch nicht mehr ändert. Aufgrund von windbedingten Druckschwankungen kann der Messdienstleister nicht ohne weiteres erkennen, wann dieser Zustand erreicht ist. Deshalb wird in diesem Artikel für einen idealisierten Ventilator mit druckunabhängigem, konstantem Volumenstrom hergeleitet, wie sich der Differenzdruck mit der Zeit entwickelt. Die wichtigste Erkenntnis: Den wesentlichsten Einfluss auf die erforderliche Wartezeit hat die Luftwechselrate bei 50 Pa, n50. Die erforderliche Wartezeit ist dazu umgekehrt proportional. Man kann eine einfache Faustformel, die Sieben‐Sekunden‐Regel, aufstellen: Dividiert man die Zahl 7 durch den Zahlenwert der Luftwechselrate bei 50 Pa (in h–1), erhält man die Wartezeit in Sekunden. Andere Einflussgrößen auf die Wartezeit sind der Strömungsexponent und die Höhe des Ziel‐Differenzdrucks.
Protein NMR Spectroscopy at 150 kHz Magic‐Angle Spinning Continues To Improve Resolution and Mass Sensitivity
Authors: Schledorn Maarten , Malär Alexander A. , Torosyan Anahit , Penzel Susanne , Klose Daniel , Oss Andres , Org Mai‐Liis , Wang Shishan , Lecoq Lauriane , Cadalbert Riccardo , Samoson Ago , Böckmann Anja , Meier Beat H. 
Published: June 2020

AbstractSpectral resolution is the key to unleashing the structural and dynamic information contained in NMR spectra. Fast magic‐angle spinning (MAS) has recently revolutionized the spectroscopy of biomolecular solids. Herein, we report a further remarkable improvement in the resolution of the spectra of four fully protonated proteins and a small drug molecule by pushing the MAS rotation frequency higher (150 kHz) than the more routinely used 100 kHz. We observed a reduction in the average homogeneous linewidth by a factor of 1.5 and a decrease in the observed linewidth by a factor 1.25. We conclude that even faster MAS is highly attractive and increases mass sensitivity at a moderate price in overall sensitivity.
Phyllosilicate‐derived Nickel‐cobalt Bimetallic Nanoparticles for the Catalytic Hydrogenation of Imines, Oximes and N‐heteroarenes
Authors: Ciotonea Carmen , Hammi Nisrine , Dhainaut Jérémy , Marinova Maya , Ungureanu Adrian , El Kadib Abdelkrim , Michon Christophe , Royer Sébastien 
Published: June 2020

AbstractThe development of cost‐effective, noble metal‐free catalytic systems for the hydrogenation of unsaturated aliphatic, aromatic, and heterocyclic compounds is fundamental for future valorization of general feedstock. With this aim, we report here the preparation of highly dispersed bimetallic Ni/Co nanoparticles (NPs), by a one‐pot deposition‐precipitation of Ni and Co phases onto mesoporous SBA‐15 silica. By adjusting the chemical composition in the starting mixture, three supported catalysts with different Ni to Co weight ratios were obtained, which were further subjected to treatments under reducing conditions at high temperatures. Characterization of the resulting solids evidenced a homogenous distribution of Ni and Co elements forming the NPs, the best results being obtained for Ni/Co‐2 : 2 samples, for which 50 wt.% Ni–50 wt.% Co NPs are found located on the surface of the residual phyllosilicate. Ni/Co‐2 : 2, presenting the best performances for the hydrogenation of 2‐methyl‐quinoline, was further evaluated in the catalytic hydrogenation of selected imines, oximes and N‐heteroarenes. Due to the high dispersion of bimetallic Ni−Co NPs, excellent properties (activity and selectivity) in the conversion of the selected substrates are reported.
Temperature Effects in Polymer Electrolyte Membrane Fuel Cells
Authors: Lochner Tim , Kluge Regina M. , Fichtner Johannes , El‐Sayed Hany A. , Garlyyev Batyr , Bandarenka Aliaksandr S. 
Published: June 2020

AbstractThe behavior of proton exchange membrane fuel cells (PEMFCs) strongly depends on the operational temperatures. In mobile applications, for instance in fuel cell electric vehicles, PEMFC stacks are often subjected to temperatures as low as −20 °C, especially during cold start periods, and to temperatures up to 120 °C during regular operation. Therefore, it is important to understand the impact of temperature on the performance and degradation of hydrogen fuel cells to ensure a stable system operation. To get a comprehensive understanding of the temperature effects in PEMFCs, this manuscript addresses and summarizes in‐ situ and ex‐ situ investigations of fuel cells operated at different temperatures. Initially, different measurement techniques for thermal monitoring are presented. Afterwards, the temperature effects related to the degradation and performance of main membrane electrode assembly components, namely gas diffusion layers, proton exchange membranes and catalyst layers, are analyzed.
Electrochemically Generated Interfacial pH Change: Application to Signal‐Triggered Molecule Release
Authors: Bollella Paolo , Melman Artem , Katz Evgeny 
Published: June 2020

AbstractElectron transfer processes during redox reactions are frequently accompanied with protonation/deprotonation processes, thus changing H+/OH− concentrations. When the redox reactions proceed at electrode surfaces, being electrochemically processed, changes in local interfacial pH are possible, particularly when the electrolyte solution is not strongly buffered. The pH gradient can be produced in the diffusion layer and its thickness depends on the rate of electrochemical process, which is measured as the current density, diffusion rates, and buffer capacity. While conventional techniques for measuring pH values are not applicable to a very thin diffusional layer, special methods have been developed for the interfacial pH measurements, including scanning electrochemical microscopy (SECM), rotating ring‐disk electrode (RRDE) measurements, various optical methods, particularly using confocal fluorescent microscopy, and others. Dramatic pH changes proceeding in a near‐electrode layer have been reported for H2O reduction/oxidation, O2 reduction, and some other electrochemical electron/proton transfer processes. These pH changes can be used to trigger some other physical processes, particularly (bio)molecule release processes from modified electrodes, which can be destabilized upon the electrochemically generated pH changes, thus releasing entrapped/loaded target molecules. This review‐type article overviews the formation and analysis of locally produced interfacial pH changes and their use for electrochemically triggered (bio)molecule release. The paper briefly reviews the research area, then concentrating on the systems designed recently by the authors.
A Nanotubular Metal–Organic Framework with a Narrow Bandgap from Extended Conjugation**
Authors: Ayhan M. Menaf , Bayraktar Ceyda , Yu Kai Bin , Hanna Gabriel , Yazaydin A. Ozgur , Zorlu Yunus , Yücesan Gündoğ 
Published: June 2020

AbstractA one‐dimensional nanotubular metal–organic framework (MOF) [Ni(Cu‐H4TPPA)]⋅2 (CH3)2NH2+ (H8TPPA=5,10,15,20‐tetrakis[p‐phenylphosphonic acid] porphyrin) constructed by using the arylphosphonic acid H8TPPA is reported. The structure of this MOF, known as GTUB‐4, was solved by using single‐crystal X‐ray diffraction and its geometric accessible surface area was calculated to be 1102 m2 g−1, making it the phosphonate MOF with the highest reported surface area. Due to the extended conjugation of its porphyrin core, GTUB‐4 possesses narrow indirect and direct bandgaps (1.9 eV and 2.16 eV, respectively) in the semiconductor regime. Thermogravimetric analysis suggests that GTUB‐4 is thermally stable up to 400 °C. Owing to its high surface area, low bandgap, and high thermal stability, GTUB‐4 could find applications as electrodes in supercapacitors.
Ultrabright Terbium Nanoparticles for FRET Biosensing and in Situ Imaging of Epidermal Growth Factor Receptors**
Authors: Charpentier Cyrille , Cifliku Vjona , Goetz Joan , Nonat Aline , Cheignon Clémence , Cardoso Dos Santos Marcelina , Francés‐Soriano Laura , Wong Ka‐Leung , Charbonnière Loïc J. , Hildebrandt Niko 
Published: June 2020

AbstractLanthanide‐doped nanoparticles (LnNPs) have become an important class of fluorophores for advanced biosensing and bioimaging. LnNPs that are photosensitized by surface‐attached antenna ligands can possess exceptional brightness. However, their functional bioconjugation remains an important challenge for their translation into bioanalytical applications. To solve this problem, we designed a ligand that can be simultaneously applied as efficient light harvesting antenna for Tb surface ions and strong linker of biomolecules to the LnNPs surfaces. To demonstrate generic applicability of the photosensitized TbNP‐bioconjugates, we applied them in two prototypical applications for biosensing and bioimaging. First, in‐solution biorecognition was shown by time‐resolved Förster resonance energy transfer (FRET) between streptavidin‐functionalized TbNPs to biotinylated dyes (ATTO 610). Second, in situ detection of ligand–receptor binding on cells was accomplished with TbNP‐antibody (Matuzumab) conjugates that could specifically bind to transmembrane epidermal growth factor receptors (EGFR). High specificity and sensitivity were demonstrated by time‐gated imaging of EGFR on both strongly (A431) and weakly (HeLa and Cos7) EGFR‐expressing cell lines, whereas non‐expressing cell lines (NIH3T3) and EGFR‐passivated A431 cells did not show any signals. Despite the relatively large size of TbNP‐antibody conjugates, they could be internalized by A431 cells upon binding to extracellular EGFR, which showed their potential as bright and stable luminescence markers for intracellular signaling.
A Six‐Armed Phenhomazine Ligand with a Potential “Turn‐Off” Copper(II) Sensing Capability through Terbium(III) Luminescence Quenching
Authors: Trupp Leandro , Bruttomesso Andrea C. , Eliseeva Svetlana V. , Petoud Stéphane , Ramírez Javier A. , Barja Beatriz C. 
Published: June 2020

AbstractHerein, the design, synthesis, and characterization of a phenhomazine ligand are described. The ligand has six pendant acetate arms designed for the combined coordination of copper(II) and lanthanide(III) ions, with the perspective of developing a “turn‐off” copper sensor. The key step for the ligand preparation was the one‐step endomethylene bridge fission of a diamino Tröger's base with a concomitant alkylation. Fluorescence and absorption spectroscopies as well as nuclear magnetic resonance (NMR) experiments were performed to analyze and understand the coordination properties of the ligand. Transition metal coordination was driven by the synergistic effect of the free nitrogen atoms of the diazocinic core and the two central acetate arms attached to those nitrogen atoms, whereas lanthanide coordination is performed by the external acetate arms, presumably forming a self‐assembled 2:2 metallosupramolecular structure. The terbium complex shows the typical green emission with narrow bands and long luminescence lifetimes. The luminescence quenching produced by the presence of copper(II) ions was analyzed. This work sets, therefore, a starting point for the development of a phenhomazine‐based “turn‐off” copper(II) sensor.
An NMR‐Based Biosensor to Measure Stereospecific Methionine Sulfoxide Reductase Activities in Vitro and in Vivo**
Authors: Sánchez‐López Carolina , Labadie Natalia , Lombardo Verónica A. , Biglione Franco A. , Manta Bruno , Jacob Reeba Susan , Gladyshev Vadim N. , Abdelilah‐Seyfried Salim , Selenko Philipp , Binolfi Andres 
Published: June 2020

AbstractOxidation of protein methionines to methionine‐sulfoxides (MetOx) is associated with several age‐related diseases. In healthy cells, MetOx is reduced to methionine by two families of conserved methionine sulfoxide reductase enzymes, MSRA and MSRB that specifically target the S‐ or R‐diastereoisomers of methionine‐sulfoxides, respectively. To directly interrogate MSRA and MSRB functions in cellular settings, we developed an NMR‐based biosensor that we call CarMetOx to simultaneously measure both enzyme activities in single reaction setups. We demonstrate the suitability of our strategy to delineate MSR functions in complex biological environments, including cell lysates and live zebrafish embryos. Thereby, we establish differences in substrate specificities between prokaryotic and eukaryotic MSRs and introduce CarMetOx as a highly sensitive tool for studying therapeutic targets of oxidative stress‐related human diseases and redox regulated signaling pathways.
Synthesis and Use of Trifluoromethylthiolated Ketenimines
Authors: Guérin Thomas , Pikun Nadiia V. , Morioka Ryutaro , Panossian Armen , Hanquet Gilles , Leroux Frédéric R. 
Published: June 2020

AbstractThe synthesis of trifluoromethylthiolated ketenimines is herein described. They are easily synthesized from the corresponding α‐trifluoromethylthiolated oximes upon activation with triflic anhydride and a base. The presumed nitrilium ion resulting from the Beckmann rearrangement is deprotonated to lead to the key intermediate, whose stability brought by the fluorinated substituent was unforeseeable. The reaction of these new building blocks with a variety of nucleophiles affords a vast array of cyclic and acyclic products bearing the valuable SCF3 moiety.
On students’ perception of low‐cost experimental equipment. Distillation in small‐scale
Authors: Bögge Laura , Lühken Arnim 
Published: June 2020

AbstractVon medizintechnischem Zubehör wie Kunststoffspritzen, Kanülen und Ampullengläsern bis hin zu Blisterpackungen oder Teelichthüllen – Experimentiervorschläge, die mit Low‐Cost‐Materialien realisiert werden, sollen eine kostengünstige, zeitökonomische, umweltfreundliche und zugleich motivierende Alternative für Schülerexperimente auch bei hohen Schülerzahlen sein. Bisher gibt es jedoch keine fachdidaktischen Studien, die den praktischen Einsatz solcher Materialien hinsichtlich genannter Aspekte auch empirisch untersuchen. Präsentiert wird daher eine Studie mit N=89 Schülerinnen und Schülern einer Realschule, die eine Low‐Cost‐Destillation durchgeführt haben und anschließend zu ihren praktischen Erfahrungen sowie ihrer Wahrnehmung hinsichtlich der Materialien befragt wurden. Die Ergebnisse der qualitativen Erhebung werden kategorisiert dargestellt und genutzt, um praktische Implikationen für den generellen Einsatz von Low‐Cost‐Materialien im Unterricht ableiten zu können.
Structure‐Based Macrocyclization of Substrate Analogue NS2B‐NS3 Protease Inhibitors of Zika, West Nile and Dengue viruses
Authors: Braun Niklas J. , Quek Jun P. , Huber Simon , Kouretova Jenny , Rogge Dorothee , Lang‐Henkel Heike , Cheong Ezekiel Z. K. , Chew Bing L. A. , Heine Andreas , Luo Dahai , Steinmetzer Torsten 
Published: June 2020

AbstractA series of cyclic active‐site‐directed inhibitors of the NS2B‐NS3 proteases from Zika (ZIKV), West Nile (WNV), and dengue‐4 (DENV4) viruses has been designed. The most potent compounds contain a reversely incorporated d‐lysine residue in the P1 position. Its side chain is connected to the P2 backbone, its α‐amino group is converted into a guanidine to interact with the conserved Asp129 side chain in the S1 pocket, and its C terminus is connected to the P3 residue via different linker segments. The most potent compounds inhibit the ZIKV protease with Ki values <5 nM. Crystal structures of seven ZIKV protease inhibitor complexes were determined to support the inhibitor design. All the cyclic compounds possess high selectivity against trypsin‐like serine proteases and furin‐like proprotein convertases. Both WNV and DENV4 proteases are inhibited less efficiently. Nonetheless, similar structure‐activity relationships were observed for these enzymes, thus suggesting their potential application as pan‐flaviviral protease inhibitors.
Do Xylylenes Isomerize in Pyrolysis?
Authors: Hirsch Florian , Pachner Kai , Fischer Ingo , Issler Kevin , Petersen Jens , Mitric Roland , Bakels Sjors , Rijs Anouk M. 
Published: June 2020

AbstractWe report infrared spectra of xylylene isomers in the gas phase, using free electron laser (FEL) radiation. All xylylenes were generated by flash pyrolysis. The IR spectra were obtained by monitoring the ion dip signal, using a IR/UV double resonance scheme. A gas phase IR spectrum of para‐xylylene was recorded, whereas ortho‐ and meta‐xylylene were found to partially rearrange to benzocyclobutene and styrene. Computations of the UV oscillator strength for all molecules were carried out and provde an explanation for the observation of the isomerization products.
The emulsifying and foaming properties of Amuniacum gum (Dorema ammoniacum) in comparison with gum Arabic
Authors: Ebrahimi Behzad , Homayouni Rad Aziz , Ghanbarzadeh Babak , Torbati Mohammadali , Falcone Pasquale M. 
Published: June 2020

AbstractIn this study, the emulsifying and foaming properties of a novel exudate gum from Dorema ammoniacum (AMG) were assessed in comparison with the well‐known gum Arabic from Acacia tree (GAC). The sunflower oil‐based emulsion (10% v/v) containing various concentrations (5%–15% w/v) of AMG and GAC was prepared. At all concentrations, AMG showed higher surface and interface activity than GAC. Increasing in AMG and GAC concentrations caused to increase and decrease in Z average, respectively. Overall, the GAC‐stabilized emulsion showed lower Z average and PDI value than the AMG‐stabilized emulsion during storage time. The sample containing AMG showed higher emulsion capacity and lower emulsion stability in comparison with the one containing GAC at all concentrations. The storage stability decreased and increased with increasing in AMG and GAC concentrations, respectively. After two‐week storage, the emulsions containing 10 and 15% AMG showed higher phase separation than those containing GAC; however, this was opposite about sample containing 5% AMG. At thermal, centrifuge, and freezing conditions, the emulsion containing 5% AMG indicated significantly higher stability than GAC samples; however, at higher concentration, opposite effect could be observed. The foaming capacity of the samples containing AMG increased from 81% to 93% by increasing gum concentration from 5% to 15%. The solutions containing AMG showed higher foam capacity than control samples (without gum) and those containing GAC at all concentrations. Increasing in AMG and GAC concentrations slightly improved foam stability, and the highest value (92%) belonged to 15% AMG solution.
In Vivo 1H MR Spectroscopy of Biliary Components of Human Gallbladder at 7T
Authors: Gajdošík Martin , Chmelík Marek , Halilbasic Emina , Pfleger Lorenz , Klepochová Radka , Trauner Michael , Trattnig Siegfried , Krššák Martin 
Published: June 2020

BackgroundPrevious in vivo proton MR spectroscopy (MRS) studies have demonstrated the possibility of quantifying amide groups of conjugated bile acids (NHCBA), olefinic lipids and cholesterol (OLC), choline‐containing phospholipids (CCPLs), taurine and glycine conjugated bile acids (TCBA, GCBA), methylene group of lipids (ML), and methyl groups of bile acids, lipids, and cholesterol (BALC1.0, BALC0.9, and TBAC) in the gallbladder, which may be useful for the study of cholestatic diseases and cholangiopathies. However, these studies were performed at 1.5T and 3T, and higher magnetic fields may offer improved spectral resolution and signal intensity.PurposeTo develop a method for gallbladder MRS at 7T.Study TypeRetrospective, technical development.PopulationTen healthy subjects (five males and five females), two patients with primary biliary cholangitis (PBC) (one male and one female), and one patient with primary sclerosing cholangitis (PSC) (female).Field Strength/SequenceFree‐breathing single‐voxel MRS with a modified stimulated echo acquisition mode (STEAM) sequence at 7T.AssessmentPostprocessing was based on the T2 relaxation of water in the gallbladder and in the liver. Concentrations of biliary components were calculated using water signal. All data were corrected for T2 relaxation times measured in healthy subjects.Statistical TestsThe range of T2 relaxation time and concentration per bile component, and the resulting mean and standard deviation, were calculated.ResultsThe concentrations of gallbladder components in healthy subjects were: NHCBA: 93 ± 66 mM, OLC: 154 ± 124 mM, CCPL: 42 ± 17 mM, TCBA: 48 ± 35 mM, GCBA: 67 ± 32 mM, ML: 740 ± 391 mM, BALC1.0: 175 ± 92 mM, BALC0.9: 260 ± 138 mM, and TBAC: 153 ± 90 mM. Mean concentrations of all bile components were found to be lower in patients.Data ConclusionThis work provides a protocol for designing future MRS investigations of the bile system in vivo.Evidence Level2Technical Efficacy Stage1