bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sampling and interpolation strategies derived from the analysis of continuous soil CO2 flux
Authors: Gana Cécilia , Nouvellon Yann , Marron Nicolas , Stape Jose Luiz , Epron Daniel 
Published: August 2016

AbstractSoil CO2 flux (Fs) can be measured either manually or automatically. While manual measurements are well suited to capture the spatial variability of Fs, automated measurements are able to capture its temporal variability at fine time scales. The manual method is the most commonly used method to estimate annual carbon budgets. However, such estimates can be biased depending on the measurement frequency, the time at which measurements are made, and the method used to interpolate Fs between two measurements. In this study, we investigated the effects of within‐day measurement frequency and of the time of measurement on the estimation of daily Fs. We also investigated the effects on cumulative Fs estimates of weekly and fortnightly sampling frequencies over several months and of the interpolation method used to cumulate Fs. We based our analyses on two complete datasets of automated measurements (one 12‐month and one 4‐month) recorded in two contrasting ecosystems (a tropical eucalypt plantation and a temperate poplar plantation). Low‐frequency time step within a day (every 360 min for the eucalypt and every 180 min for the poplar plantations) was sufficient to capture mean daily Fs accurately. Furthermore, in the tropical site, measurements averaged over any 6h period provided good estimates of the daily flux. By contrast, biases were observed in the temperate site. With one measurement per week, linear interpolation methods provided accurate cumulative fluxes at both sites. However, all interpolation methods failed to produce robust estimates of cumulative Fs in the temperate plantation with one measurement every two weeks. Automated measurements will help to select the best time slot for manual measurements or to correct manual measurements from the apparent deviation between measurements collected during the sampling period and the 24 h‐mean CO2 flux. It will also be useful to elaborate empirical equations used to cumulate Fs obtained manually. Combining manual and automated methods will enhance the accuracy of annual soil carbon budgets in forest plantations.
Intraoperative assessment of laryngeal malignancy using elastic light single‐scattering spectroscopy: A pilot study
Authors: Turhan Murat , Yaprak Neslihan , Sircan‐Kucuksayan Aslinur , Ozbudak Irem , Bostanci Asli , Derin Alper , Canpolat Murat 
Published: August 2016

Objectives/HypothesisThe elastic light single‐scattering spectroscopy (ELSSS) system is a new tool for the real‐time diagnosis of cancerous lesions. In the current study, we have employed ELSSS to investigate its ability in differentiation between normal and cancerous larynx tissues ex vivo.Study DesignBasic science study in assessment of laryngeal malignancy using spectroscopy.MethodsELSSS spectra of the larynx tissue were acquired using a single‐fiber optical probe. Ex vivo spectroscopic measurements were acquired on 95 laryngeal lesions of 40 patients. Average slopes of the spectra in the wavelength range of 450 to 750 nm were calculated. The signs of the spectral slopes were positive for benign and negative for cancerous larynx tissues. Histopathology results were used as a gold standard to define sensitivity and specificity.ResultsThe ELSSS system correctly defined 38 out of 41 malignant tissues as cancerous; three of them were misclassified as benign. All benign tissues were correctly classified. Moderate, severely dysplastic, and malignant tissues were correctly classified as cancerous. The system could not classify mild dysplastic tissues either benign or cancerous, whereas nearly half of them were classified as benign and the other half as malignant. The signs of the spectral slopes were used as a discrimination parameter between benign and cancerous (moderate, severely dysplastic, and malignant) lesions with a sensitivity and specificity of 94% and 100%, respectively.ConclusionsThe ELSSS system has the potential to be used as an adjunctive tool in the diagnosis of cancerous laryngeal tissues in real time and noninvasively. This new diagnostic technique may reduce the number of negative biopsies.Level of EvidenceNA Laryngoscope, 127:611–615, 2017
Efficacy of Erbium:YAG laser treatment compared to topical estriol treatment for symptoms of genitourinary syndrome of menopause
Authors: Gaspar Adrian , Brandi Hugo , Gomez Valentin , Luque Daniel 
Published: August 2016

ObjectivesThe objective of this prospective comparative cohort study was to establish the effectiveness and safety of Erbium:YAG (Er:YAG) laser treatment for genitourinary syndrome of menopause and to compare it with an established topical estriol treatment.MethodsFifty patients with genitourinary syndrome of menopause were divided into two groups. The estriol group received a treatment of 0.5 mg estriol ovules for 8 weeks and the laser group was first treated for 2 weeks with 0.5 mg estriol ovules 3 times per week to hydrate the mucosa and then received three sessions with 2,940 nm Er:YAG laser in non‐ablative mode. Biopsies were taken before and at 1, 3, 6, and 12 months post‐treatment. Maturation index, maturation value and pH where recorded up to 12‐months post‐treatment, while the VAS analysis of symptoms was recorded up to 18 months post‐treatment.ResultsStatistically significant (P < 0.05), reduction of all assessed symptoms was observed in the laser group at all follow‐ups up to 18 months post‐treatment. Significant improvement in maturation value and a decrease of pH in the laser group was detected up to 12 months after treatment. The improvement in all endpoints was more pronounced and longer lasting in the laser group. Histological examination showed changes in the tropism of the vaginal mucosa and also angiogenesis, congestion, and restructuring of the lamina propria in the laser group. Side effects were minimal and of transient nature in both groups, affecting 4% of patients in the laser group and 12% of patients in the estriol group.ConclusionsOur results show that Er:YAG laser treatment successfully relieves symptoms of genitourinary syndrome of menopause and that the results are more pronounced and longer lasting compared to topical estriol treatment. Lasers Surg. Med. 49:160–168, 2017. © 2016 The Authors. Lasers in Surgery and Medicine Published by Wiley Periodicals, Inc.
In vivo endoscopic Doppler optical coherence tomography imaging of the colon
Authors: Welge Weston A. , Barton Jennifer K. 
Published: August 2016

Background and ObjectiveColorectal cancer (CRC) remains the second deadliest cancer in the United States. Several screening methods exist; however, detection of small polyps remains a challenge. Optical coherence tomography (OCT) has been demonstrated to be capable of detecting lesions as small as 1 mm in the mouse colon, but detection is based on measuring a doubling of the mucosa thickness. The colon microvasculature may be an attractive biomarker of early tumor development because tumor vessels are characterized by irregular structure and dysfunction. Our goal was to develop an endoscopic method of detecting and segmenting colon vessels using Doppler OCT to enable future studies for improving early detection and development of novel chemopreventive agents.MethodWe conducted in vivo colon imaging in an azoxymethane (AOM)‐treated mouse model of colorectal cancer using a miniature endoscope and a swept‐source OCT system at 1,040 nm with a 16 kHz sweep rate. We applied the Kasai autocorrelation algorithm to laterally oversampled OCT B‐scans to resolve vascular flow in the mucosa and submucosa. Vessels were segmented by applying a series of image processing steps: (i) intensity thresholding; (ii) two‐dimensional matched filtering; and (iii) histogram segmentation.ResultsWe observed differences in the vessels sizes and spatial distribution in a mature adenoma compared to surrounding undiseased tissue and compared the results with histology. We also imaged flow in four young mice (two AOM‐treated and two control) showing no significant differences, which is expected so early after carcinogen exposure. We also present flow images of adenoma in a living mouse and a euthanized mouse to demonstrate that no flow is detected after euthanasia.ConclusionWe present, to the best of our knowledge, the first Doppler OCT images of in vivo mouse colon collected with a fiber‐based endoscope. We also describe a fast and robust image processing method for segmenting vessels in the colon. These results suggest that Doppler OCT is a promising imaging modality for vascular imaging in the colon that requires no exogenous contrast agents. Lasers Surg. Med. 49:249–257, 2017. © 2016 Wiley Periodicals, Inc.
Einflüsse kleiner Zusätze von Niob oder Cer auf Korrosion und Kriechen von Incoloy 800 in Co‐H2O‐H2‐Atmosphären
Authors: Hemptenmacher Jürgen , Grabke Hans Jürgen 
Published: August 2016

AbstractIn oxidierenden und aufkohlenden Atmosphären werden Fe‐Ni‐Cr‐Legierungen bei hohen Temperaturen und Kriechen der Werkstoffe aufgekohlt, dadurch daß eine Kohlenstoffübertragung durch Risse in der Oxidschicht erfolgt. Bei Kriechversuchen in CO‐H2O‐H2‐Atmosphären bei 1000°C mit verschieden Legierungen auf der Basis von Incoloy 800 konnte die Kohlenstoffaufnahme mit der Dehnung des Werkstoffs korreliert werden.Legierungszusätze von Niob im Bereich 0,2 bis 1% bewirkten Änderungen der Kriechgeschwindigkeit, eine Abnahme für >0,35% Nb und eine Zunahme für >0,35%. Der Kriechwiderstand für die höheren Nb‐Konzentrationen (1% Nb) konnte durch eine Lösungsglühung bei hoher Temperatur (1200°C) verbessert werden.Niob hemmt die Aufkohlung sehr wirksam. Dieser Einfluß ist durch die Bildung einer inneren Oxidschicht aus Al‐ und Nb‐Oxiden unterhalb der äußeren Cr2O3‐Schicht zu erklären. Auch ein Zusatz von Cer (0,06%) hat günstige Auswirkungen auf den Kriechwiderstand und den Widerstand gegen Aufkohlung des Werkstoffs.
Korrosion von Chemieemail durch wäßrig‐neutrale Medien
Authors: Lorentz R. 
Published: August 2016

AbstractChemieemails sind hochbeständige Spezialgläser im Schmelzverbund mit Stahl, ein Verbundwerkstoff, der vorzugsweise im Chemiebetrieb als korrosionsfestes all‐round Material für Rührbehälter und Zubehör eingesetzt wird. Die Korrosionsbeständigkeit des Glasemails gegenüber wäßrig neutralen Medien wird überprüft durch gravimetrische Auswertung von Laborversuchen mit allseitig emaillierten Probekörpern. Für den Angriff des reinen Wassers werden für Email die vom Massivglas bekannten Vorgänge bestätigt. Wird jedoch, wie im Chemiebetrieb üblich, stattdessen Leitungswasser genommen, oder sind im Wasser Neutralsalze wie Chloride, Phosphate, Hydrogenkarbonate vorhanden, werden deutlich höhere Emailabtragsraten gefunden; umgekehrt wirken sich Aluminium(III) oder organische Verbindungen im Wasser positiv für Email aus. Durch die Wahl von praxisanalogen Versuchsparametern können die quantitativen Ergebnisse auf die Realität übertragen werden und verhelfen damit dem Betreiber zu einer optimalen Nutzung seiner emaillierten Apparate.
Influence of nitrogen addition on microstructure and pitting corrosion resistance of austenitic weld metals
Authors: Mudali U. Kamachi , Dayal R. K. , Gill T. P. S. , Gnanamoorthy J. B. 
Published: August 2016

AbstractA study to investigate the role of nitrogen in improving the pitting corrosion resistance of types 316 and 304 stainless steel weld metals has been attempted. Weld metals were prepared by autogenous TIG welding process with argon‐nitrogen mixture as the shielding gas. Delta‐ferrite measurements, made with Magne‐Gage, showed the absence of delta‐ferrite in all the samples of type 316 ss weld metal whereas for type 304 ss it decreased from 3.8 to 0 FN with increase in the levels of nitrogen. Potentiodynamic anodic polarization studies carried out on weld metal samples in deaerated neutral chloride medium showed improved resistance to pitting attack with increase in the amount of nitrogen. This improvement in pitting resistance could be due to the dissolution of nitrogen and formation of inhibiting compounds at the pit sites. The ESCA results of the anodically polarized weld metal samples showed the presence of nitrogen in a compound form. SEM and optical microscopic studies of the pitted samples showed that the initiation sites for pitting attack were triple points, austenite centres and delta‐ferrite/austenite interfaces.
Kohlenstoffaustausch zwischen Stahl und Natrium als Korrosionserscheinung
Authors: Borgstedt H. U. , Frees G. 
Published: August 2016

AbstractNeue Meßmethoden ermöglichen die Bestimmung von Kohlenstoff in flüssigem Natrium im Konzentrationsbereich unter 1 μg C/gNa. Dadurch wird der Kohlenstoffaustausch zwischen Natrium und austenitischem Stahl vor allem bei Entkohlungsvorgängen verständlich. Der Kohlenstoffaustausch vom Stahl zum Natrium kann zu einer Schädigung der Werkstoffe in der Nähe der Oberfläche führen. So ist in solchen Fällen die Verminderung der Zeitstandfestigkeit des Stahls 1.4948 bei 550°C beobachtet worden. Die Schädigung durch Entkohlung schreitet allerdings nur langsam fort, wie sich im Falle von Proben mit größerem Durchmesser gezeigt hat, in denen praktisch keine Reduktion der Zeitstandfestigkeit auftrat.
Korrosionsvérhalten hochlegierter Stähle im System H2O/NH3/CO2/H2S/HCN/HSCN (Teil 1)
Authors: Schröpfer J. , Wendler‐Kalsch E. 
Published: August 2016

AbstractEs wurde der Einfluß von Schwefelwasserstoff, Blausäure, Polysulfid und Rhodanwasserstoff auf das Korrosionsverhalten hochlegierter Stähle und einer Nickelbasislegierung in Ammoncarbonatlösung mit elektrochemischen Methoden untersucht. Die wesentlichen Mechanismen für die Stärke des Korrosionsangriffs werden anhand schematischer Diagramme aufgezeigt.Geringe H2S‐Gehalte erhöhen die Korrosionsrate, hohe H2S‐Gehalte erniedrigen sie durch Bildung schützender Deckschichten. Polysulfid stabilisiert aufgrund des kathodischen Teilstroms der Schwefelreduktion das freie Korrosionspotential beim Redoxpotential im Passivbereich der Werkstoffe. HCN erhöht einerseits die Korrosionsrate aktivierter Proben in H2S‐haltigen Lösungen durch Entfernen sulfidischer Deckschichten, andererseits inhibiert es die Korrosion in HSCN‐haltigen Lösungen. Auch in H2S‐haltigen Lösungen sind inhibierende Effekte und instabile Passivität bei Proben mit oxidischer Deckschicht möglich. Die Stärke des Korrosionsangriffs in HSCN‐haltigen Lösungen wird durch CO2 erhöht und ist abhängig vom Nickelgehalt der Werkstoffe.
Eigenschaftsprofil des neuentwickelten Stahls X2 CrNiMnMoN 23 1764
Authors: Grundmann R. , Gümpel P. , Ladwein Th. 
Published: August 2016

AbstractDurch eine abgewogene Legierungszusammensetzung war es möglich, den hochlegierten Edelstahl X 2 CrNiMnMoN 23 17 6 4 mit einem Stickstoffgehalt von > 0,4% bei konventioneller Erzeugung herzustellen. Der Werkstoff hat ein vollaustenitisches Gefüge, eine 0,2%‐Dehngrenze von > 420 N/mm2 und ist schweißtechnisch gut verarbeitbar. Im Lochfraßtest nach ASTM G 48‐76 erreicht er eine kritische Lochfraßtemperatur von > 85°C, die auch im geschweißten Zustand nur geringfügig niedriger liegt. Der Stahl stellt damit eine interessante Lösung für Anwendungen in der chemischen Industrie dar, in denen hochlegierte Edelstähle aus Beständigkeitsgründen versagen und teure Sonderwerkstoffe, z. B. Ni‐Basislegierungen, nicht unbedingt erforderlich sind.
Halbleitereigenschaften von Passivfilmen und ihre Bedeutung für die Lochkorrosion
Authors: Schmuki P. , Böhni H. 
Published: August 2016

AbstractMit Hilfe von Mott‐Schottky‐Analysen und photoelektrochemischen Untersuchungen wurden die Halbleitereigenschaften von Passivfilmen auf AISI 304 charakterisiert und mit dem Auftreten von Stromtransienten, welche aus metastabilen Lochkorrosionsvorgängen resultieren, verglichen.Es zeigte sich, daß das Potential, unter welchem keine Lochinitiierungsvorgänge mehr beobachtbar sind, mit dem Potential des Ladungsnullpunkts im Passivfilm (Flachbandpotential) zusammenfällt. Ein einfaches elektrostatisches Modell wird vorgeschlagen, welches zeigt, daß der erste Schritt des Lochbildungsvorganges ‐ nämlich die Adsorption von lochfraßerzeugenden Anionen‐erst ermöglicht wird, wenn im Passivfilm eine positive Raumladung auftritt.Dieses Modell wird weiter gestützt durch das Auftreten eines Maximums in der Transientenzahl, welches in einem Potentialbereich erfolgt, in dem auch drastische Änderungen in den elektronischen Eigenschaften des Passivfilmes festzustellen sind.
Sporopollenin, a Natural Copolymer, is Robust under High Hydrostatic Pressure
Authors: Montgomery Wren , Potiszil Christian , Watson Jonathan S. , Sephton Mark A. 
Published: August 2016

Lycopodium sporopollenin, a natural copolymer, shows exceptional stability under high hydrostatic pressures (10 GPa) as determined by in situ high pressure synchrotron source Fourier transform infrared spectroscopy. This stability is evaluated in terms of the component compounds of the sporopollenin: p‐coumaric acid, phloretic acid, ferulic acid, and palmitic and sebacic acids, which represent the additional n‐acid and n‐diacid components. This high stability is attributed to interactions between these components, rather than the exceptional stability of any one molecular component. This study proposes a biomimetic solution for the creation of polymer materials that can withstand high pressures for a multitude of uses in aeronautics, vascular autografts, ballistics, and light‐weight protective materials.
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Generation Mechanism of Oxidation Products during the Air Atmosphere Oxidation of SEBS/PP Blends: Tracked by 2D Correlation Infrared Spectroscopy
Authors: Liu Yongcheng , Zhou Tao , Zhang Aiming 
Published: August 2016

In this paper, the generation mechanism of oxidation products during the oxidation of the polystyrene‐block‐poly(ethylene‐co‐1‐butene)‐block‐polystyrene copolymer (SEBS)/poly(propylene) (PP) blend in air atmosphere is investigated using temperature‐dependent FTIR combined with 2D correlation infrared spectroscopy. Differential scanning calorimetry, thermogravimetric analysis, and perturbation‐correlation moving‐window 2D correlation FTIR spectroscopy find three processes associated with SEBS/PP oxidative degradation. The 2D correlation analysis is used to study the sequential order of groups' movement of reactants and oxidation products involved in the main oxidation. It is found that the main oxidation starts from the molecular chains of PP and EB blocks of SEBS. It firstly forms COC structure between the molecular chains of PP and the EB blocks, resulting in the cross‐linked structure. Aliphatic ketones are formed via the β‐scission of the main chains of PP or the EB blocks. Then, aliphatic ketones are converted into aliphatic esters. After the above reactions, the S blocks of SEBS begin to oxidize. The S blocks are generated into aromatic ketones through β‐scission. The formation of lactones in the molecular chains of PP and EB blocks is followed via the radical biting back. Finally, aromatic ketones generated from the S blocks are converted into aromatic esters through the reactions of Norrish I, the radical coupling, and so on.
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The Synthesis and Characterization of the Poly[N‐vinylpyrrolidone‐co‐ethylidene‐bis‐3‐(N‐vinyl‐2‐pyrrolidone)] Hydrogel Matrix for Drug Delivery to the Gastrointestinal Tract
Authors: Hrib Jakub , Sirc Jakub , Hobzova Radka , Krumbholcova Eva , Zak Ales , Stankova Barbora , Slanar Ondrej , Hromadka Robert , Michalek Jiri 
Published: August 2016

SummaryHydrogels based on copolymers of N‐vinylpyrrolidone and ethylidene‐bis‐3‐(N‐vinyl‐2‐pyrrolidone) (EBVP) were prepared as polymer matrices for controlled release of high loads of hydrophilic compounds into the gastrointestinal tract. EBVP was synthesized and used as a crosslinking agent for the N‐vinylpyrrolidone monomer. The polymerization mixtures, containing 65–80 wt.% of the model pharmacologically active compound, were polymerized to create cylindrical formulations. The release experiments were carried out under conditions corresponding to the digestive tract. Various compositions of hydrogel matrices were tested to reveal the influence of the active compound content and the crosslinking ratio on the release kinetics. Processes such as hydrogel swelling, dissolution and formulation disintegration were evaluated. The results obtained show that the system offers many possibilities to control the drug release to meet various medicinal requirements.
Evaluation of Grain Size by Small‐Angle X‐Ray Scattering for a Block Copolymer Film in Which Cylindrical Microdomains Are Perpendicularly Oriented
Authors: Ohnogi Hiroshi , Sasaki Sono , Sakurai Shinichi 
Published: August 2016

SummaryMethod of evaluation of grain size of hexagonally‐packed cylindrical microdomains is presented by taking as an example the data from the polystyrene‐block‐polyethylenebutylene‐block‐polystyrene (SEBS) triblock copolymer film, where the polystyrene cylinders are embedded in the polyethylenebutylene matrix with being oriented perpendicular to the surface of the film. For this purpose, the two‐dimensional small‐angle X‐ray scattering was measured by illuminating X‐ray beam from the side of the film. The procedure is similar to the method how to evaluate the crystallite size of polymer, using the peak width of crystalline reflection in the wide‐angle X‐ray diffraction (WAXD) measurement. While single crystal is used as the standard sample for the case of WAXD because it can be postulated that the crystallite size is infinity in the single crystal, we propose here to use collagen as a standard sample for the SAXS measurement, since collagen forms very regular stacking of texture with 65.3 nm repeating period and the number of the stacking texture is infinitely large. It was confirmed that the grain size evaluated by the SAXS method was in sufficient accord with the result of the transmission electron microscopic observation.
Contact Angle Studies in XLPE Hybrid Nanocomposites with Inorganic Nanofillers
Authors: Jose Josmin P. , Abraham Jiji , Maria Hanna J. , Varughese K.T. , Thomas Sabu 
Published: August 2016

SummaryWetting properties and surface energy characteristics of cross‐linked polyethylene (XLPE) with different nanofillers (such as Al2O3, SiO2, TiO2, and clay) were studied using contact angle measurements with water and dimethyl sulfoxide (DMSO) as solvents. Similar trend of variation of contact angle was found for both the kinds of systems. In nanocomposites, the high packing density of the macromolecules on the super molecular level (with marked ordering even in quasi‐amorphous regions) create steric and kinetic hindrances for penetration of solvent molecules, which may result in high degree of solvent resistance, confirmed by the transition of the material from wetting region (for neat XLPE) to a non‐ wetting region (for nanocomposites). Results of contact angle studies have been correlated with the morphology and microstructure development in each system by electron microscopy.
Molecular Weight Distribution of Core Cross‐Linked Star Polymers
Authors: Tobita Hidetaka 
Published: August 2016

The analytic formulas for the number‐ and weight‐average molecular weights (MWs) of the core cross‐linked star polymers (CCSPs) are proposed. In the arm‐first method, the number‐ and weight‐average MWs of the arms ( and ) and CCSPs ( and ) can be determined experimentally. From , , and weight fraction of the arms wA (or the core, wC = 1−wA), the number‐average number of the arms () and the number‐average core MW () can be determined. Because of the correlation between the core MW and the number of the arms, the general solution of for CCSPs presented requires attention to the nature of correlation. When the average and variance of the arm‐number distribution are linear function of core MW, the weight‐average number of the arms () and the weight‐average core MW () can be determined. The approximate estimation method for is also discussed.
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