bluuebunny/crossref_metadata_2025_split huggingface dataset:
Untersuchungen zur Luftqualität an Verkehrswegen mit Drohnen
Authors: Baum Anja , Günther Lucas , Düring Ingo , Wehner Birgit 
Published: September 2018

AbstractDrohnen, die auch als UAV/UAS (Unmanned Aerial Vehicles/Systems) oder RPAS (Remotely Piloted Aircraft Systems) bezeichnet werden, werden derzeit neben der Anwendung im privaten Umfeld für eine große Menge an kommerziellen Anwendungen diskutiert, entwickelt und eingesetzt. Die Messung von Luftqualitätsparametern mit auf Drohnen mitgeführten Kleingeräten ist in diesem Zusammenhang eine sehr junge Disziplin.Durch die Anwendung auf Drohnen können so z. B. Kurzzeitmessungen in Höhen‐ und Längsprofilen oder anderen Messanordnungen als Ergänzung von Daten kontinuierlich arbeitender Referenzverfahren oder zur Einschätzung der besten Positionierung von festen Messstationen vor einem Aufbau durchgeführt werden.Im Rahmen eines verkehrsträgerübergreifenden Expertennetzwerks wurde eine Machbarkeitsstudie durchgeführt, in der auf dem Markt befindliche Systeme gegenübergestellt und Empfehlungen für den Einsatz an Straßen, Wasserstraßen sowie Bahntrassen abgeleitet wurden. Mit ersten Testmessungen konnten darüber hinaus Hinweise auf die Eignung von Messsystemen gewonnen und Erfahrungen mit den Besonderheiten der Messung an Verkehrswegen gesammelt werden.
Development of a method for quantitative determination of the cytotoxic agent piplartine (piperlongumine) in multiple skin layers
Authors: Carvalho Vanessa F. M. , Giacone Daniela V. , Costa‐Lotufo Leticia V. , Silveira Edilberto Rocha , Lopes Luciana B. 
Published: September 2018

AbstractThis study reports the development of a simple and reproducible method, with high rates of recovery, to extract the cytotoxic agent piplartine from skin layers, and a sensitive and rapid UV‐HPLC method for its quantification. Considering the potential of piplartine for topical treatment of skin cancer, this method may find application for formulation development and pharmacokinetics studies to assess cutaneous bioavailability. Porcine skin was employed as a model for human tissue. Piplartine was extracted from the stratum corneum (SC) and remaining viable skin layers (VS) using methanol, vortex homogenization and bath sonication, and subsequently assayed by HPLC using a C18 column, and 1:1 (v/v) acetonitrile–water (adjusted to pH 4.0 with acetic acid 0.1%) as mobile phase. The quantification limit of piplartine was 0.2 μg/mL (0.6 μm), and the assay was linear up to 5 μg/mL (15.8 μm), with within‐day and between‐days assay coefficients of variation and relative errors <15%. Piplartine recovery from SC and VS varied from 86 to 96%. The method was suitable to assay samples from skin penetration studies, enabling detection of differences in cutaneous delivery in different skin compartments resulting from treatment with various formulations and time periods.
Development and validation of a hydrophilic interaction ultra‐high‐performance liquid chromatography–tandem mass spectrometry method for rapid simultaneous determination of 19 free amino acids in rat plasma and urine
Authors: Wen Yongqing , Yuan Xuemei , Qin Feng , Zhao Longshan , Xiong Zhili 
Published: September 2018

AbstractDetermination of amino acids in biofluids is a challenging task because of difficulties deriving from their high polarity and matrix interference. A simple, reliable and high‐throughput hydrophilic interaction UHPLC–MS/MS method was developed and validated for the rapid simultaneous determination of 19 free amino acids in rat plasma and urine samples in this paper. Hydrophilic method with a Waters Acquity UPLC BEH Amide column (100 × 2.1 mm,1.7 μm) was used with a gradient mobile phase system of acetonitrile and water both containing 0.2% formic acid. The analysis was performed on a positive electrospray ionization mass spectrometer via multiple reaction monitoring. Samples of 10 μL plasma and 50 μL urine were spiked with three deuterated internal standards, pretreated with 250 μL acetonitrile for one‐step protein precipitation and a final dilution of urine samples. Good linearities (r > 0.99) were obtained for all of the analytes with the lower limit of quantification from 0.1 to 1.2 μg/mL. The relative standard deviation of the intra‐day and inter‐day precisions were within 15.0% and the accuracy ranged from −12.8 to 12.7%. The hydrophilic interaction UHPLC–MS/MS method was rapid, accurate and high‐throughput and exhibited better chromatography behaviors than the regular RPLC methods. It was further successfully applied to detect 19 free amino acids in biological matrix.
Rescuing mesenchymal stem cell regenerative properties on hydrogel substrates post serial expansion
Authors: Rao Varsha V. , Vu Michael K. , Ma Hao , Killaars Anouk R. , Anseth Kristi S. 
Published: September 2018

AbstractThe use of human mesenchymal stem/stromal cells (hMSCs) in most clinical trials requires millions of cells/kg, necessitating ex vivo expansion typically on stiff substrates (tissue culture polystyrene [TCPS]), which induces osteogenesis and replicative senescence. Here, we quantified how serial expansion on TCPS influences proliferation, expression of hMSC‐specific surface markers, mechanosensing, and secretome. Results show decreased proliferation and surface marker expression after five passages (P5) and decreased mechanosensing ability and cytokine production at later passages (P11‐P12). Next, we investigated the capacity of poly(ethylene glycol) hydrogel matrices (E ~ 1 kPa) to rescue hMSC regenerative properties. Hydrogels reversed the reduction in cell surface marker expression observed at P5 on TCPS and increased secretion of cytokines for P11 hMSCs. Collectively, these results show that TCPS expansion significantly changes functional properties of hMSCs. However, some changes can be rescued by using hydrogels, suggesting that tailoring material properties could improve in vitro expansion methods.
Effects of introducing innovative teaching methods in engineering classes: A case study on classes in an Indian university
Authors: Subramanian Dhenesh Virallikattur , Kelly Patricia 
Published: September 2018

AbstractTechnology has been revolutionized in the past few decades and its impacts on student learning have not been fully explored. The digital divide between a student's personal technology usage and its use within the classroom remains to be bridged. This study focuses on using technology‐based innovative teaching methods with engineering classes and understanding their impact on students. The findings suggest that these learners benefited from and prefer to use innovative teaching methods backed by technology support in class. Students deprived of such innovative methods and technology would prefer to have them introduced to aid their learning experience. The study strengthens the need for decision makers in educational institutions to invest in innovative teaching methods supported by technology in order to provide a better learning platform for students, particularly in India, where engineering graduates are regarded as lacking essential skills in communication and innovation.
A Concise Synthesis of Potential COX Inhibitor BRL‐37959 and Analogs Involving Bismuth(III) Catalyzed Friedel−Crafts Acylation
Authors: Ahmed Shamsul Arefin , Hinz Damon J. , Jellen Marcus J. , Hossain M. Mahmun 
Published: September 2018

AbstractWe report the development of a concise method of synthesizing possible cyclooxygenase (COX) inhibitor BRL‐37959, which is believed to be a potent nonsteroidal anti‐inflammatory drug (NSAID). The four‐step synthesis greatly increased the efficiency of compound production from commercially available salicylaldehydes. The synthesis involved an optimized, bismuth(III) trifluoromethanesulfonate catalyzed benzoylation of a benzofuran ring.
Contemporary Photoligation Chemistry: The Visible Light Challenge
Authors: Offenloch Janin T. , Gernhardt Marvin , Blinco James P. , Frisch Hendrik , Mutlu Hatice , Barner‐Kowollik Christopher 
Published: September 2018

AbstractCatalyst‐free and bond‐forming light‐induced reactions have seen an unprecedented renaissance in the realm of soft matter materials science due to their efficiency, spatio‐temporal controllability and, sometimes, photoreversible nature. However, many of these reactions rely on the application of high energy UV light that can cause photo‐degradation and is inapplicable in biological environments. If up‐conversion systems or two‐photon processes are to be avoided, strategies for red‐shifting catalyst‐free ligation technology are critically required. This Concept article introduces the reader to recent methods that lead to efficient, catalyst‐free visible‐light‐induced ligation chemistry based on polyaromatic substituted photoreactive compounds—pyrene and anthracene—and, furthermore, emphasizes the broad and facile applicability of these molecules in polymeric material design. Concomitantly, we highlight that a careful action plot analysis of photochemical reactivity can provide deep insights into reactivity patterns, far beyond those suggested by the absorption spectrum. Indeed, we suggest that an action plot analysis is necessary for the evaluation of any photochemical system and its response to structural chemical changes.
Corannulenes with Electron‐Withdrawing Substituents: Synthetic Approaches and Resulting Structural and Electronic Properties
Authors: Haupt Axel , Lentz Dieter 
Published: September 2018

AbstractCorannulene is a multifaceted polyaromatic compound. It has many interesting properties; for example, it has a bowl‐shaped molecular structure that, in addition, undergoes a dynamic inversion process. It has attracted much attention within the last decades. This is not only due to its structural properties but also its electronic properties and its various potential applications to materials chemistry. Here, synthetic approaches towards corannulene derivatives with electron‐withdrawing substituents are summarized. This includes both selective and unselective methods. Further, the electrochemical properties, that is, the reduction potentials, are analyzed and compared. As a main conclusion, one can state that the electron affinity depends roughly linearly on the number of substituents. Finally, the structural behavior of the substituted buckybowls in the solid state is highlighted. This also allows a general statement about the influence of the electronic and steric nature of substituents on the molecular structures and the solid‐state packing of the corannulene derivatives.
Structural Effects of Fusicoccin upon Upregulation of 14‐3‐3‐Phospholigand Interaction and Cytotoxic Activity
Authors: Ohkanda Junko , Kusumoto Atsushi , Punzalan Louvy , Masuda Ryoma , Wang Chenyu , Parvatkar Prakash , Akase Dai , Aida Misako , Uesugi Motonari , Higuchi Yusuke , Kato Nobuo 
Published: September 2018

AbstractFusicoccins (FCs) exhibit various cellular activities in mammalian cells, but details of the mechanism of action are not fully understood. In this study, we synthesized two pairs of model derivatives of FCs differing only in the presence and absence of a 12‐hydroxyl group and evaluated their binding to a 14‐3‐3 protein together with various mode 1 and mode 3 phosphopeptide ligands. Our results demonstrate that the 12‐hydroxyl group hampers binding to 14‐3‐3 with mode 1 phospholigands, presumably due to steric repulsion with the i+2 residue. Furthermore, cell‐based evaluations showed that only non‐substituted FCs exhibit significant cytotoxicity and all 12‐hydroxyl derivatives were inactive, demonstrating a clear correlation with their ability to form ternary complexes with 14‐3‐3 and a mode 1 ligand. These results suggest that binding to 14‐3‐3 and a partner protein(s) possessing a mode 1 sequence plays a role in the mechanism of action of 12‐non‐substituted FCs.
Inspecting the Electronic Architecture and Semiconducting Properties of a Rosette‐Like Supramolecular Columnar Liquid Crystal
Authors: Feringán Beatriz , Folcia César L. , Termine Roberto , Golemme Attilio , Granadino‐Roldán José M. , Navarro Amparo , Serrano José Luis , Giménez Raquel , Sierra Teresa 
Published: September 2018

AbstractComputational and experimental studies unravel the structural and electronic properties of a novel supramolecular liquid crystal built through a hierarchical assembly process resulting in an H‐bonded melamine rosette decorated with peripheral triphenylenes. The six‐fold symmetry of the mesogen facilitates the formation of a highly organized hexagonal columnar mesophase stable at room temperature. X‐ray diffraction and electron density maps confirm additional intra‐ and intercolumn segregation of functional subunits, and this paves the way for 1D charge transport. Indeed, hole mobility has been measured and found to be higher than for related mesogens. DFT calculations of HOMO and LUMO levels and parameters such as reorganization energy and transfer integral of the rosette structure have been achieved, and not only validate the columnar organization but also establish the way it translates into a favorable electronic architecture and molecular orbital interactions to promote charge carrier mobility.
The use of tranexamic acid for on‐demand and prophylactic treatment of hereditary angioedema—A systematic review
Authors: Horiuchi Takahiko , Hide Michihiro , Yamashita Kouhei , Ohsawa Isao 
Published: September 2018

AbstractHereditary angioedema (HAE), caused by inherited deficiency of C1 esterase inhibitor (C1‐INH), is characterized by recurring subcutaneous and/or submucosal edema. Although its efficacy remains controversial, tranexamic acid (TXA) is used to treat HAE in some countries. We analyzed TXA as an on‐demand and prophylactic treatment in patients with HAE. Published data were systematically sourced from PubMed and Embase. All retained articles underwent grading/bias assessment using the “SIGN” grading system, and the quality of retained studies was determined following assessment of design and methodology. Of 353 studies identified, 31 were included. On‐demand treatment and prophylactic treatment were assessed in five (N = 103) and 28 studies (N = 231), respectively. The majority of studies (80%) demonstrated that on‐demand TXA was ineffective for skin, abdominal, or laryngeal swellings. In a single randomized controlled trial, the median time to relief of symptoms was 2 and 12 hours for icatibant and TXA, respectively (P < 0.001). For prophylaxis, while ~50% of case series, case reports, and observational studies reported beneficial effects of TXA, newer therapies, for example, icatibant and pdC1‐INH, were more effective. One study found that breakthrough attacks during TXA prophylaxis lasted significantly longer compared with C1‐INH (median time to resolution; 7 vs 3 hours, P = 0.016). Many studies failed to report safety data (16/31, 52%); however, pruritus, vomiting, and diarrhea were noted in some patients. There is no evidence for on‐demand use of TXA in HAE and limited evidence for prophylaxis. While TXA may be more beneficial than no treatment, newer, more effective therapies should be used when available.
Electrochemical Sensor Based on AgNPs‐NNH Nanocomposites for Hydrogen Peroxide Detection by Zero Current Potentiometry
Authors: Fu Yanyi , Hao Huan , Liu Xiaoli , Zheng Jianbin 
Published: September 2018

AbstractThe layered nickel nitrate hydroxide (NNH) nickel base material was prepared by using hydrothermal method, and the AgNPs were synthesized on the surface of NNH. The layered AgNPs‐NNH nanocomposites were used to construct electrochemical sensor for hydrogen peroxide detection. The morphology, composition and structure of the sensing interface materials were characterized and the relationship between zero current potential signals towards hydrogen peroxide and the response performance was explored. The results of field emission electron microscope (FESEM) and transmission electron microscope (TEM) showed that the NNH was layered material with a uniform thickness of 60 nm, and AgNPs evenly dispersed on the surface of NNH layer, with the size of 15 nm and 23 nm, respectively. Based on zero current potentiometry, the electrochemical results indicated that the linear range was from 1.0 nmol/L to 1.0 mmol/L, with a detection limit of 0.3 nmol/L and a sensitivity of 33.7 μV·mM–1·cm–2. Compared to the chronoamperometry, the detection limit was reduced four orders of magnitude.
Effects of sauna bath on heart failure: A systematic review and meta‐analysis
Authors: Källström Miikka , Soveri Inga , Oldgren Jonas , Laukkanen Jari , Ichiki Tomoko , Tei Chuwa , Timmerman Mark , Berglund Lars , Hägglund Hans 
Published: September 2018

BackgroundSauna bath has potential as a lifestyle treatment modality for heart failure (HF). It is important to analyze the current evidence to help suggest paths of future study and potential for clinical application.HypothesisSauna bath has a positive effect on HF patients.MethodsPubMed, Cochrane Library, and CINAHL databases were searched to identify randomized and nonrandomized controlled studies to compare effects of sauna bath with no sauna bath. Studies were searched for both infrared sauna bath and Finnish sauna bath. The strength of evidence was rated using a modified GRADE approach. Out of 1444 studies, nine met the inclusion criteria and were included in this review. Seven of these nine studies were included in the meta‐analysis. Only studies with infrared sauna bath met the inclusion criteria.ResultsIn the meta‐analysis, exposure to an infrared sauna bath in 60°C for 15 minutes, followed by a 30‐minute rest in warm environment, five times a week for 2 to 4 weeks, was associated with a significant reduction in B‐type natriuretic peptide, cardiothoracic ratio, and an improvement in left‐ventricular ejection fraction. There was no significant effect on left‐ventricular end‐diastolic diameter, left atrial diameter, systolic blood pressure, or diastolic blood pressure. The strength of evidence varied from moderate to insufficient.ConclusionInfrared sauna bath was associated with short‐term improvement in cardiac function. More evidence is needed about long‐term effects of sauna bath and the effects of a Finnish sauna on cardiovascular health among patients with HF or other cardiovascular diseases.
An On‐Chip Method for Long‐Term Growth and Real‐Time Imaging of Brain Organoids
Authors: Karzbrun Eyal , Tshuva Rami Yair , Reiner Orly 
Published: September 2018

AbstractBrain organoids are an emerging technique for studying human neurodevelopment in vitro, with biomedical implications. However, three‐dimensional tissue culture poses several challenges, including lack of nutrient exchange at the organoid core and limited imaging accessibility of whole organoids. Here we present a method for culturing organoids in a micro‐fabricated device that enables in situ real‐time imaging over weeks with efficient nutrient exchange by diffusion. Our on‐chip approach offers a means for studying the dynamics of organoid development, cell differentiation, cell cycle, and motion. © 2018 by John Wiley & Sons, Inc.
Heterogeneous Nucleation onto Monoatomic Ions: Support for the Kelvin‐Thomson Theory
Authors: Tauber Christian , Chen Xiaoshuang , Wagner Paul E. , Winkler Paul M. , Hogan Christopher J. , Maißer Anne 
Published: September 2018

AbstractIn this study, the process of heterogeneous nucleation is investigated by coupling a high‐resolution differential mobility analyser (DMA) to an expansion‐type condensation particle counter, the size‐analyzing nuclei counter (SANC). More specifically, we measured the activation probabilities of monoatomic ions of both polarities by using n‐butanol as condensing liquid. All seed ions were activated to grow into macroscopic sizes at saturation ratios well below the onset of homogeneous nucleation, showing for the first time that the SANC is capable of detecting sub‐nanometer sized, atomic seed ions. The measured onset saturation ratios for each ion were compared to the Kelvin‐Thomson (KT) theory. Despite the fact that certain dependencies of activation behaviour on seed ion properties cannot be predicted by the KT theory, it was found that with a simple adjustment of the n‐butanol molecular volume (9–15 % lower compared to bulk properties) good agreement with experimental results is achievable. The corresponding density increase may result from the dipole‐charge interaction. This study thus offers support for the application of the KT model for heterogeneous, ion‐induced nucleation studies at the sub‐nanometer level.
Photoinduced Intramolecular Charge Transfer and Hyperpolarizability Coefficient in Push‐Pull Pyridinium Salts with Increasing Strength of the Acceptor Group
Authors: Cesaretti Alessio , Bonaccorso Carmela , Elisei Fausto , Fortuna Cosimo G. , Mencaroni Letizia , Spalletti Anna 
Published: September 2018

AbstractThe synthesis of three push‐pull cationic dyes is reported here together with a photophysical study carried out by stationary and ultrafast spectroscopies. The hyperpolarizability (β) values of the three molecules have been estimated through a simple solvatochromic method based on conventional, low‐cost equipment, which had been tested previously with success in our laboratory. The investigated pyridinium salts showing strong negative solvatochromism bear the same piperidine ring as a strong electron‐donor group and the same thiophenes as electron‐rich π‐linkers, but differ in terms of the N‐substituent on the electron‐acceptor pyridinium unit, namely N‐methyl in compound A, N‐pyrimidin‐2yl in B and N‐2,4‐dinitrophenyl in C. The derived β values were found to increase (in the order A<B<C) along with the increasing electron‐acceptor strength of the pyridinium substituent, with the highest polarizability being estimated for the derivative bearing the strongest electron‐withdrawing substituent dinitrobenzene. State‐of‐the‐art femtosecond transient absorption measurements evidenced fast kinetics and dynamics in the singlet excited state in agreement with charge transfer (CT) processes promoted by excitation, with a proper ICT state observed in the case of C. This finding confirms the efficiency of photoinduced intramolecular CT as a significant factor that affects the NLO response.
Whole Genome Next‐Generation Sequencing Mutation Identification in Pseudomonas aeruginosa
Authors: Cetinbas Murat , Yu Shen , Sadreyev Ruslan I. 
Published: September 2018

AbstractIdentification of spontaneous or chemically induced bacterial mutations is a powerful tool for investigation of molecular mechanisms, including the mechanism of action of novel antibiotics. However, a major bottleneck to this approach has been the identification of the causative mutation underlying a phenotype of interest. Until recently, this has required time‐consuming genetic analysis. However, the advent of relatively inexpensive and rapid next‐generation sequencing (NGS) technologies has revolutionized the correlation of bacterial phenotypes and genotypes. In this article we describe a simple bioinformatics pipeline to identify differences between sequenced bacterial genomes. We also describe the procedures involved in growing, extracting, and purifying DNA, and preparation of sequencing libraries for one bacterial species, Pseudomonas aeruginosa. Similar protocols will be applicable to other bacterial species. © 2018 by John Wiley & Sons, Inc.