bluuebunny/crossref_metadata_2025_split huggingface dataset:
Schlanke vorgespannte Stützen aus UHPC – Experimentelle Untersuchung und Nachrechnung
Authors: Illich Günther , Tue Nguyen Viet , Freytag Bernhard 
Published: August 2014

AbstractUltrahochfester Faserbeton ist aufgrund seiner hohen Druckfestigkeit und seiner Duktilität für den Einsatz in Druckgliedern besonders gut geeignet. Auch bei stark stabilitätsgefährdeten Stützen bringt UHPC große Vorteile, die durch zentrisches Vorspannen der Stützen nutzbar gemacht werden. Die Schlankheit solcher “Architekturstützen” kann bei gleichbleibender Traglast stark angehoben werden, was jedoch sehr bald mit dem Verlassen des normativ geregelten Bereichs einhergeht. Aus diesem Grund müssen die geltenden Bemessungsregeln auf deren Gültigkeit für solche Bauteile überprüft bzw. adaptiert werden. Der hier vorgestellte Beitrag zielt darauf ab, die grundlegenden Zusammenhänge des Tragverhaltens von im Spannbett vorgespannten Stützen aus UHPC mit unveränderlicher Lastausmitte umfassend darzulegen. Dies erfolgt über Bauteilversuche und deren nichtlineare Nachrechnung. Um die Bauteilduktilität beurteilen zu können, wird eine spezielle Regelungstechnik entwickelt, mit deren Hilfe die Versuche weit über die Traglast gefahren werden können. Die Nachrechnung erfolgt einerseits mit kommerzieller Software und andererseits mithilfe von eigenen Programmen, die auch die Simulation der Schwind‐ und Kriecheffekte zufriedenstellend ermöglichen.Slender, prestressed high performance concrete columns – experimental investigation and calculationThe outstanding compression strength of Ultra high performance concrete makes this material perfectly apt for struts. Even columns with a high risk of buckling will benefit from UHPC, especially if they are centrically prestressed. The slenderness of such “Architectural Columns” can considerably increase without loss of load carrying capacity. Since that extended slenderness is far from fitting into the application field of the current design regulations, those have to be evaluated with respect to their suitability for such novel members. If required they should also be adapted.This paper aims at the fundamental understanding of the load carrying behaviour of pre‐tensioned columns made of fibre reinforced UHPC under compression with the same load eccentricity at both ends. Therefore, full‐scale experiments and their recalculation are carried out. A reliable evaluation of the ductility of columns needs sufficient experimental results beyond the ultimate load. For this reason a special method of loading control was developed and applied. The recalculations are carried out by the use of commercial software and also with own software which makes sure that the consideration of creep and shrinkage works as desired.
Praxisorientierte Ermittlung von Ausschalfristen
Authors: Schwabach Enrico 
Published: August 2014

AbstractUnter bestimmten Voraussetzungen kann die Ausschalfrist für Betonbauteile vereinfacht praxisnah, z. B. über tabellierte Werte, abgeschätzt werden. Alternativ stehen aufwendigere Verfahren zur Verfügung, welche je nach Bedarf bzw. in Abhängigkeit von der für die Bauaufgabe erforderlichen Genauigkeit herangezogen werden können. Im Folgenden wird die praxisorientierte Ermittlung von Ausschalfristen im Zusammenhang mit dem Eurocode 2 und DIN EN 13670/DIN 1045‐3 diskutiert.Practice‐oriented determination of stripping timesUnder certain conditions, the stripping times of concrete members can be estimated in a simplified way (e.g. tabulated values are provided for practice). Depending on the required precision more complex methods are available. In the following a practice‐oriented determination of stripping times according to Eurocode 2 and DIN EN 13670/DIN 1045‐3 is discussed.
Mechanism of Action of AminoCBIs: Highly Reactive but Highly Cytotoxic Analogues of the Duocarmycins
Authors: Tercel Moana , Pruijn Frederik B. , O'Connor Patrick D. , Liyanage H. D. Sarath , Atwell Graham J. , Alix Sonia M. 
Published: August 2014

AbstractDuocarmycins are highly cytotoxic natural products that have potential for development into anticancer agents. Herein we describe proposed but previously unidentified NH analogues of the DNA‐alkylating subunit and characterise these by solvolysis studies, NMR and computational modelling. These compounds are shown to be the exclusive intermediates in the solvolysis of their seco precursors and to possess very similar structural features to the widely studied O‐based analogues, apart from an unusually high basicity. The measured pKa of 10.5 implies that the NH compounds are fully protonated under physiological conditions. Remarkably, their extremely high reactivity (calculated hydrolysis rate 108 times higher for protonated NH compared to the neutral O analogue) is still compatible with potent cytotoxicity, provided the active species is formed in the presence of cells. These surprising findings are of relevance to the design of duocarmycin‐based tumour‐selective therapies.
Effect of Multi‐Walled Carbon Nanotubes on Glucose Oxidation by Glucose Oxidase or a Flavin‐Dependent Glucose Dehydrogenase in Redox‐Polymer‐Mediated Enzymatic Fuel Cell Anodes
Authors: Osadebe Isioma , Leech Dónal 
Published: August 2014

AbstractThe addition of multi‐walled carbon nanotubes (MWCNTs) to enzymatic electrodes based on either glucose oxidase (GOx), or an oxygen‐insensitive flavin adenine dinucleotide‐dependent glucose dehydrogenase (FADGDH), increases the amount of {Os(4,4′‐dimethyl‐2,2′‐bipyridine)2[poly(vinylimidazole)]10Cl}Cl redox polymer at the electrode surface, indicating that MWCNTs provide a surface for the immobilisation of film components. Glucose oxidation is highest for films with 68 % (w/w) MWCNTs, and a decrease is observed with larger amounts; this decrease is related to a decrease in retained enzyme activity. Enzymatic electrodes provide 4.2 mA cm−2 current density at 0.12 V versus Ag/AgCl, for GOx‐based electrodes, compared to 2.7 mA cm−2 for FADGDH‐based electrodes in 50 mM phosphate‐buffered saline containing 150 mM NaCl at 37 °C. Current densities of 0.52 and 1.1 mA cm−2 are obtained for FADGDH and GOx‐based electrodes, respectively, operating at physiologically relevant 5 mM glucose concentrations. These enzymatic electrodes, thus, show promise for application as anodes in enzymatic fuel cells for in vivo or ex vivo power generation.
Water uptake and hydraulic redistribution under a seasonal climate: long‐term study in a rainfed olive orchard
Authors: Nadezhdina Nadezhda , Ferreira Maria Isabel , Conceição Nuno , Pacheco Carlos Arruda , Häusler Melanie , David Teresa Soares 
Published: August 2014

AbstractHydraulic redistribution plays a relevant role in the water relations of trees in climates with alternation between warm/dry and cold/wet periods. We aim to illustrate the ability of Mediterranean deep‐rooted rainfed olive trees to maintain transpiration during the hot dry season and to redistribute soil water through roots, tending to temporarily homogenize soil moisture vertically. Sap flow was monitored by the heat field deformation method for 2·5 years in the stem, lignotuber, medium and shallow roots of an olive tree tracing the long‐term variations in the patterns of transpiration, water uptake and hydraulic redistribution. During the same period, soil water content and meteorological data were measured and related to sap flow. Results show that hydraulic redistribution within the rhizosphere buffers the seasonal and long‐term water deficits. Under high evaporative demand during the dry summer, the deeper roots connected to stem through the lignotuber uptake water supporting transpiration needs and reducing the intensive drying of the upper soil layers. Copyright © 2014 John Wiley & Sons, Ltd.
Stereoselective Synthesis of cis,cis‐Configured Vicinal Triamines
Authors: Schulte Adrian , Saito Susumu , Wünsch Bernhard 
Published: August 2014

AbstractThe first stereoselective synthesis of a cis,cis‐configured vicinal triamine was achieved, starting from N‐cyclohexenylpyrrolidone (10). The reaction sequence consists of the stereoselective construction of the trans‐configured 1,3‐diamide 14, trans‐to‐cis isomerization via enols or enamines, and subsequent highly stereoselective reduction of the intermediate imine 17D to the amine 18A. The postulated reaction pathway explains the observed stereoconvergence and is supported by calculation of the heats of formation of its intermediates at the PM3 level. LiAlH4 reduction of 18A yielded the tetracyclic aminal 19, which was converted into the pyrrolidinylquinoxaline 7, which showed low to moderate affinity towards κ and σ1 receptors.
A Factor Analytical Approach to the Efficient Futures Market Hypothesis
Authors: Westerlund Joakim , Norkute Milda , Narayan Paresh Kumar 
Published: August 2014

AbstractMost empirical evidence suggests that the efficient futures market hypothesis, henceforth referred to as EFMH, stating that spot and futures prices should cointegrate with a unit slope on futures prices, does not hold, a finding at odds with many theoretical models. This article argues that these results can be attributed in part to the low power of univariate tests, and that the use of panel data can generate more powerful tests. The current article can be seen as a step in this direction. In particular, a newly developed factor analytical approach is employed, which is very general and, in addition, free of the otherwise so common incidental parameters bias in the presence of fixed effects. The approach is applied to a large panel covering 17 commodities between March 1991 and August 2012. The evidence suggests that the EFMH cannot be rejected once the panel evidence has been taken into account. © 2014 Wiley Periodicals, Inc. Jrl Fut Mark 35:357–370, 2015
Copolymerization of n‐Butyl Acrylate and Styrene: Terminal vs Penultimate Model
Authors: Hamzehlou Shaghayegh , Reyes Yuri , Hutchinson Robin , Leiza Jose Ramon 
Published: August 2014

The batch solution copolymerization of styrene and n‐butyl acrylate over a range of styrene feed compositions is analyzed by in situ 1H NMR to monitor individual and overall monomer conversions, as well as by 13C NMR and size exclusion chromatography (SEC)/multi‐angle light scattering (MALS) for the branching density and molecular weight, respectively. Both the terminal and penultimate models, using rate coefficients taken from the literature, fail to predict the full extent of the reduced overall copolymerization rate observed when the styrene composition in the feed is increased. After estimation of uncertain model parameters, the terminal model provides a good representation of the experimental dataset. The estimated overall efficiency of the initiator decreases (from the typically employed 0.65 to 0.35) and the cross‐termination increases from the values corresponding to the geometric mean of the homopolymerization termination rate coefficients.
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Prolonged erythropoietin treatment does not impact gene expression in human skeletal muscle
Authors: Christensen Britt , Nellemann Birgitte , Thorsen Kasper , Nielsen Morten Muhlig , Pedersen Steen B. , Ornstrup Marie Juul , JØrgensen Jens Otto L. , Jessen Niels 
Published: August 2014

ABSTRACTIntroductionWe tested for the presence of erythropoietin receptor (Epo‐R) in human skeletal muscle and alterations in gene expression after prolonged use of an erythropoiesis‐stimulating agent (ESA).MethodsNine healthy men were treated with ESA for 10 weeks (darbepoietin alfa). Muscle biopsies were collected before and after treatment. Alterations in gene expression were evaluated by gene array. Western blot and PCR analysis were used to test for Epo‐R presence in human skeletal muscle.ResultsVery low Epo‐R mRNA levels were found, but a new and sensitive antibody did not identify Epo‐R protein in human skeletal muscle. The between‐subject variation in skeletal muscle gene expression was greater than that observed in response to prolonged ESA treatment.ConclusionsErythropoietin is unlikely to exert direct effects in human skeletal muscle due to a lack of Epo‐R protein. Furthermore, prolonged ESA treatment does not seem to exert either direct or indirect effects on skeletal muscle gene expression. Muscle Nerve 51: 554–561, 2015
Screening for psychological distress in cancer: renewing the research agenda
Authors: Salmon Peter , Clark Louise , McGrath Elly , Fisher Peter 
Published: August 2014

AbstractObjectiveAlthough health policy for cancer care promotes screening of patients for emotional distress, the utility and validity of screening have been questioned. Continued research to refine detection of distress or to evaluate outcomes of screening programmes is unlikely to end this controversy. Instead, we need to identify more fundamental research questions that address the validity or utility of screening in this context.MethodWe critically and selectively review research and policy literature on psychological screening in cancer care, drawing also from research literature about the nature of psychological needs in cancer care and from relevant literature on psychological screening in mental health.ResultsWe identify three broad research questions: (i) Apart from intensity of distress, what further information should screening seek about the context of distress, psychological processes that promote distress and patients' own perspective on their needs? (ii) What are the implications of the contextual dependence of disclosure of emotional feelings, given that screening questions can be asked in contexts ranging from an impersonal questionnaire to dialogue with a trusted practitioner? (iii) How should a screen be responded to, given the inherent uncertainty associated with screening results and given that distress in a cancer context can indicate instrumental as well as psychological needs?ConclusionsExamining these questions will mean exchanging a diagnostic framework for screening, in which health need is indicated by the presence of a psychological disorder, for a public health framework, in which health need is identified from multiple perspectives. Copyright © 2014 John Wiley & Sons, Ltd.
HABITAT‐ORIENTED SAMPLING OF MACROINVERTEBRATES AFFECTS THE DETERMINATION OF ECOLOGICAL STATUS IN TEMPORARY MEDITERRANEAN RIVER SYSTEMS
Authors: Leitão F. , Hughes S. J. , Máximo I. , Atanasova N. , Furtado A. , Chicharo L. 
Published: August 2014

ABSTRACTInter‐annual and annual variation in precipitation levels in Mediterranean temporary river systems strongly influence riverine flow regimes and as a result habitat' availability for biological assemblages. Under‐sampling of less well‐presented microhabitats in such changeable, dynamic systems can result in information loss leading to misclassification of Water Framework Directive (WFD) compliant ecological status, with serious consequences for Programmes of Measures in River Basin Management Plans. This paper compares two benthic macroinvertebrate sampling protocols tested in intermittent Mediterranean streams (n = 40) in the Algarve region of southern Portugal. The officially adopted WFD compliant European assessment system for the ecological quality of rivers using benthic macroinvertebrates, a composite sampling protocol, focuses sampling a greater area of the most representative microhabitats at a given sampling site (proportional habitat sampling). A non‐proportional habitat sampling protocol was applied to test the assumption that taxa may have preference for different microhabitats and that this could influence classification of ecological status. Variation was detected in the levels of similarity in the structure and the composition of the benthic macroinvertebrate community within sampling sites and rivers, based on material collected using the two collection methods. Ecological index scores and biotic metrics were higher when the non‐proportional oriented sampling protocol was utilized resulting in a ‘good ecological status’ classification at sites that had been classified as ‘Bad’ using the official WFD, Decision tree analysis results indicated that changes in the area of individual microhabitats sampled among protocols was the principal driver behind differences in ecological status derived. The results indicate that more realistic classifications could be achieved in intermittent Mediterranean rivers when considering and sampling less well‐represented microhabitat types (non‐proportional sampling) rather than distributing sampling effort by the proportion of the dominant habitat present as currently used for the WFD protocol. The application of the non‐proportional microhabitat‐based approach, which accounts for selective preferences of some benthic macroinvertebrate taxa, would ensure that a greater proportion of a given site community contributes to the assessment. Copyright © 2014 John Wiley & Sons, Ltd.
Non-targeted metabolomic reveals the effect of salt stress on global metabolite of halotolerant yeast Candida versatilis and principal component analysis
Authors: Qi Wei , Fan Zhen-Chuan , Wang Chun-Ling , Hou Li-Hua , Liu Jin-Fu , Cao Xiao-Hong 
Published: August 2014

Abstract
As one of the major microbes in the soy sauce fermentation, Candida versatilis enriches the flavor and improves the quality of soy sauce. In this study, a combination of five different GC-MS and LC-MS-based metabolome analytical approaches was used to analyze the intracellular, extracellular and whole metabolites of C. versatilis. Our results found out that a total of 132, 244 and 267 different metabolites were detectable from the intracellular, extracellular and whole part, respectively. When exposed to 0. 9 and 18 % salt, respectively, 114, 123 and 129 different intracellular metabolites, 184, 200 and 178 extracellular metabolites and 177, 188 and 186 whole metabolites were detected, respectively. Our data showed that salt enhances the metabolic capacity of C. versatilis, especially its amino acid and enhances the synthesis and secretion of some metabolites of C. versatilis, especially the aldehydes and phenols, such as vanillin, guaiacol and 5-hydroxymethylfurfural. Our data also showed that special attention has to be paid to the generation of biogenic amines when C. versatilis was treated with salt.
Self‐reported rates of interpersonal conflict vary as a function of questionnaire format: Why age‐related trends in disagreement (and other events) may not be what they seem
Authors: Dirghangi Shrija , Laursen Brett , Puder Justin , Bjorklund David F. , DeLay Dawn 
Published: August 2014

ABSTRACTTwo studies examine whether self‐reports of interpersonal conflict differ as a function of how the question is asked. In Study 1, 56 U.S. college students (M = 20.7 years) completed different versions of a questionnaire, four times, at one week intervals. Participants reported more conflicts with the aid of memory prompts than without, an effect that was especially strong when questions focused on events from the previous day. In Study 2, 123 middle‐school students (M = 11.08 years) and 128 primary school students (M = 8.2 years) from the same region completed one of two questionnaires describing conflict during the previous day. Children reported more conflicts with memory prompts than without. The effect was twice as strong for younger children than older children. The findings suggest that increases in reports of conflict across the transition into adolescence may be due to improvements in the ability to recall and recount events in the absence of memory cues.
Medium-chain TAG attenuate hepatic oxidative damage in intra-uterine growth-retarded weanling piglets by improving the metabolic efficiency of the glutathione redox cycle
Authors: Zhang Hao , Chen Yueping , Li Yue , Yang Li , Wang Jianjun , Wang Tian 
Published: August 2014

The present study investigated the effects of medium-chain TAG (MCT) on hepatic oxidative damage in weanling piglets with intra-uterine growth retardation (IUGR). At weaning (mean 21 (sd1·06) d of age), twenty-four IUGR piglets and twenty-four normal-birth weight (NBW) piglets were selected according to their birth weight (BW; IUGR: mean 0·95 (sd0·04) kg; NBW: mean 1·58 (sd0·04) kg) and weight at the time of weaning (IUGR: mean 5·26 (sd0·15) kg; NBW: mean 6·98 (sd0·19) kg) and fed either a soyabean oil (SO) diet (containing 5 % SO) or a MCT diet (containing 1 % SO and 4 % MCT) for 28 d. IUGR piglets exhibited poor (P< 0·05) growth performance, lower (P< 0·05) metabolic efficiency of hepatic glutathione (GSH) redox cycle, and increased (P< 0·05) levels of reactive oxygen species, apoptosis and necrosis in hepatocytes compared with NBW piglets. The MCT diet increased (P< 0·05) the average daily gain and feed efficiency of piglets during the first 4 weeks after weaning. Furthermore, MCT diet-fed piglets had a higher (P< 0·05) GSH:oxidised glutathione ratio and increased (P< 0·05) activities of glucose-6-phosphate dehydrogenase (G6PD) and GSH reductase. The expression ofG6PDwas up-regulated (P< 0·05) by the MCT diet irrespective of BW. Moreover, malondialdehyde concentrations in the liver and apoptosis and necrosis levels in hepatocytes were decreased (P< 0·05) by the MCT diet irrespective of BW. These results indicate that MCT might have auxiliary therapeutic potential to attenuate hepatic oxidative damage in IUGR offspring during early life, thus leading to an improvement in the metabolic efficiency of the hepatic GSH redox cycle.
Changes in plasma amino acid profiles, growth performance and intestinal antioxidant capacity of piglets following increased consumption of methionine as its hydroxy analogue
Authors: Li Hao , Wan Haifeng , Mercier Yves , Zhang Xiaoling , Wu Caimei , Wu Xiuqun , Tang Li , Che Lianqiang , Lin Yan , Xu Shengyu , Tian Gang , Wu De , Fang Zhengfeng 
Published: August 2014

The aim of the present study was to determine whether early weaning-induced growth retardation could be attenuated by increased consumption of methionine asdl-methionine (DLM) ordl-2-hydroxy-4-methylthiobutyrate (HMTBA) in both lactating sows and weaned piglets. Therefore, diets containing DLM and HMTBA at 25 % of the total sulphur-containing amino acids (AA) present in the control (CON) diet were fed to lactating sows and weaned piglets and their responses were evaluated. Compared with the CON diet-fed sows, the HMTBA diet-fed sows exhibited a tendency (P< 0·10) towards higher plasma taurine concentrations and the DLM diet-fed sows had higher (P< 0·05) plasma taurine concentrations, but lower (P< 0·05) isoleucine concentrations. Suckling piglets in the HMTBA treatment group had higher (P< 0·05) intestinal reduced glutathione (GSH) content, lower (P< 0·05) oxidised glutathione (GSSG):GSH ratio, and higher (P< 0·05) plasma cysteine and glutathione peroxidase (GPx) activity than those in the CON and DLM treatment groups. The feed intake (P< 0·05) and body weight of piglets averaged across post-weaning (PW) days were higher (P< 0·05) in the HMTBA treatment group than in the DLM treatment group and were higher (P< 0·05) and tended (P< 0·10) to be higher, respectively, in the HMTBA treatment group than in the CON treatment group. Increased (P< 0·05) GSSG content and GSSG:GSH ratio and down-regulated (P< 0·05) expression of nutrient transport genes were observed in the jejunum of piglets on PW day 7 than on PW day 0. On PW day 14, the HMTBA diet-fed piglets had higher (P< 0·05) intestinal GSH content than the CON diet-fed piglets and higher (P< 0·05) plasma GPx activity, villus height and goblet cell numbers than the CON diet- and DLM diet-fed piglets. In conclusion, early weaning-induced growth retardation appears to be attenuated through changes in plasma AA profiles and elevation of growth performance and intestinal antioxidant capacity in piglets following increased consumption of methionine as HMTBA.