bluuebunny/crossref_metadata_2025_split huggingface dataset:
Experimentelle Untersuchungen zum dynamischen Verhalten von Eisenbahnbrücken mit Schotteroberbau
Authors: Kirchhofer Johannes , Fink Josef 
Published: May 2011

AbstractIm Zuge der Erhöhung der Reisegeschwindigkeit der Westbahnstrecke auf bis zu 250 km/h wurden in den letzten Jahren von Seiten der ÖBB zahlreiche dynamische Brückenmessungen in Auftrag gegeben. Dabei konnte festgestellt werden, dass Berechnung und Realität meist sehr stark differieren können. Dies liegt einerseits im Umstand, dass für Berechnungsmodelle im Zuge der Aufwandsminimierung immer gewisse Vereinfachungen in der Modellbildung vorgenommen werden müssen und somit die realen Verhältnisse nur bedingt abgebildet werden können, zum anderen ergeben sich durch konservative Annahmen der Normung stark auf der sicheren Seite liegende Eingangsgrößen. Gerade im Hinblick auf dynamische Berechnungen gibt die Norm für die anzusetzende Dämpfung des Systems sehr stark auf der sicheren Seite liegende Werte vor, welche gerade für Eisenbahnbrücken mit Schotteroberbau die realen Verhältnisse nicht abbilden. Um diesem Umstand Folge zu leisten, wurden in Zusammenarbeit mit der ÖBB Versuche an einer realen Brückenstruktur durchgeführt. Die folgenden Seiten beinhalten die Ergebnisse und Auswertungen der dynamischen Schwingungsmessungen einer Eisenbahnbrücke aus Stahl auf der Strecke der Donauuferbahn zwischen St. Valentin und Krems.Dynamic behaviour of a railway bridge with ballast superstructure — field trials and modal identification. The technical progress in the construction of railway bridges enables the realisation of more and more slender and lightweight structures. Also, the axle loads and travelling speeds of the operating trains were constantly increased over the past. Caused by these developments, the dynamic behaviour of railway bridges is getting more and more important for the design and construction of new structures or refurbishment purposes. To investigate the dynamic interaction between the ballast superstructure and the structure of the bridge, an experimental bridge has been built and tested with an innovative system of two eccentric weight vibration generators based on the methods of experimental modal analysis using the resonance method. The experiments show that the ballast superstructure affects the damping and the dynamic behaviour of the bridge in a nonlinear way. The following paper deals with the verification of the results achieved in the laboratory by carrying out field trails on existing railway bridges.
Digitale Vision und gebaute Wirklichkeit — Über das Bauen von geometrisch anspruchsvollen Gebäudehüllen
Authors: Ziegler René , Schneider Benjamin 
Published: May 2011

AbstractIm letzten Jahrhundert haben Architekten für ihre Entwürfe vorwiegend geometrische Grundformen wie Würfel und Quader, Zylinder‐, Kegel‐ oder Torus‐Flächen verwendet. Seit den 60‐er Jahren des vorigen Jahrhunderts werden die digitalen Werkzeuge der Designer aber ständig weiterentwickelt (Nurbsflächen) und tragen nun zu einer quasi unbegrenzten Erweiterung des Formenvokabulars bei. Computer und entsprechende Software (CAD/CAM) dienen nicht nur zur Erstellung von technischen Zeichnungen oder zur Ansteuerung von CNC‐Maschinen in der Fertigung, sondern unterstützen vor allem auch die Konzeption neuartiger biomorpher Formen. Die Arbeit mit digitalen Werkzeugen und Inhalten ist zum globalen Industriestandard geworden.Die Tendenz, einfache lineare Formen aufzugeben, welche aus einer überschaubaren Anzahl einzelner ähnlicher Elemente bestehen, und diese durch einzigartige Skulpturen zu ersetzen, entstammt der schöpferischen Vision der Künstler und deren Willen, Dinge weit ab vom banalen Gebrauchsgegenstand zu schaffen. Diese Landmarks sind zu Sinnbildern von Eleganz, Anmut, Fortschritt und Innovation geworden.Computerized vision and built reality — About the designing of complex building shapes. For the past century, architects have been using cylinders, cones, rotational and ruled surfaces for their designs. Meanwhile computers and corresponding software are necessary for throughout the architectural design and planning of the construction industry. Whether it is the draft of drawings or the design of new complex building shapes, working with digital content has become the standard for the industry. There is a continuous tendency to give up linear forms with easily manageable numbers of the same elements. Free‐form structures originated by the creativity of architects beginning in the last decade of the previous millennium have developed to symbols of elegance, grace, progress, and innovation. The construction of arbitrarily shaped building envelopes necessitates the computerized design and calculation of large numbers of unique elements.This iconic or landmark architecture is commonly used to emphasize the brands of enterprises. To transfer the architectural concept into built reality, an intense collaboration of geometrical and structural engineers combined with production and material management experience is necessary to standardize complexity and hence increase the feasibility of the design.
Neue Bogenbrücke für die Koralmbahn — Mit Schwung von Graz nach Klagenfurt
Authors: La Poutré Dagowin , Vill Markus 
Published: May 2011

AbstractDieser Aufsatz beschreibt eine vor kurzem fertiggestellte Brücke über die zukünftige Koralmbahn im Süden Österreichs. Die Brücke wurde auf Basis des Corporate Design der Österreichischen Bundesbahnen (ÖBB) für die gesamte Koralmbahn konzipiert. Die Straßenbrücke besteht aus auskragenden Stahlbetonwiderlagern mit zwei freistehenden nach innen geneigten Stahlbögen, von denen die Verbundfahrbahnplatte abgehängt ist. Im vorliegenden Beitrag wird neben dem allgemeinen Entwurf besonders auf die Produktion der Bögen und deren Einfluss auf die Bemessung eingegangen.New arch bridge for the Koralm Railway. This paper describes a recently built bridge over the future Koralm Railway in southern Austria. The bridge was designed according to the corporate design requirements of the Österreichischen Bundesbahnen (ÖBB, Austrian Federal Railways). The bridge constitutes concrete cantilevering abutments with two free standing steel arches in a basket handle arrangement. From these arches a composite bridge deck is suspended. In this paper special attention is paid to the production of the arches and the influence it has on the structural design.
Stabilitätsnachweis von Stäben mit einfachsymmetrischen Querschnitten — Eurocode‐konforme Regelungen im österreichischen Nationalen Anhang zur EN 1993‐1‐1
Authors: Greiner Richard , Taras Andreas , Kaim Peter 
Published: May 2011

AbstractDie Stabilitätsregeln für Stäbe im derzeitigen Eurocode EN 1993‐1‐1 sehen Bemessungsformeln — sogenannte Interaktionsformeln für Druck und Biegung — vor, die für den Hauptanwendungsbereich von gewalzten oder geschweißten I‐, H‐ und Hohlprofilen mit doppelt‐symmetrischen Querschnitten hergeleitet worden sind. Eine Erweiterung dieser Regeln auf einfach‐symmetrische Querschnitte wurde im österreichischen Nationalen Anhang ÖNORM B 1993‐1‐1 vorgenommen. Diese Regeln und ihr Hintergrund werden im vorliegenden Beitrag beschrieben.Stability analysis of members with mono‐symmetric section shapes — Eurocode conforming rules in the Austrian National Annex for the EN 1993‐1‐1. The rules for member stability given in the existing Eurocode EN 1993‐1‐1 provide design formulae, called interaction‐formulae for bending and axial compression, which cover the main application range of rolled and welded pro files with double‐symmetric I‐, H‐ or hollow sections. An extension of these rules to mono‐symmetric section shapes has been implemented in the Austrian National Annex ÖNORM B 1993‐1‐1. The structure of these rules and the background are given in the present paper.
The chronic administration of cerebrolysin induces plastic changes in the prefrontal cortex and dentate gyrus in aged mice
Authors: Juárez Ismael , González Deniss Janeth , Mena Raúl , Flores Gonzalo 
Published: May 2011

AbstractCerebrolysin (Cbl) is a mixture of neuropeptides with effects similar to the endogenous neurotrophic factors and is considered one of the best drugs used in the treatment of dementias such as Alzheimer's disease (AD). In brains with AD, morphological changes in the dendrites of pyramidal neurons of the prefrontal cortex (PFC) and hippocampus have been reported. These changes are reflected particularly in the decrement of both the dendritic tree and spine density. Here we evaluated the effect of this drug on the dendrites of pyramidal neurons of the PFC and CA1 dorsal hippocampus and granule cells from the dentate gyrus (DG) and medium spiny neurons of the nucleus accumbens (NAcc) of aged mice. Cbl (5 ml kg−1, i.p.) was administered daily for 60 days to 6‐month‐old mice. Dendritic morphology was studied by the Golgi‐Cox stain procedure followed by Sholl analysis at 8 months ages. In all Cbl‐treated mice a significant increase in dendritic spine density and dendritic length in pyramidal neurons of the PFC and granule cells of the DG was observed. Interestingly, the enhancement in dendritic length was close to the soma in pyramidal neurons of the PFC whereas in granule neurons of the DG the increase in dendritic length was further from the soma. Our results suggest that Cbl induces plastic modifications of dendritic morphology in the PFC and DG. These changes may explain the therapeutic effect seen in AD patients treated with Cbl. Synapse 2011. © 2011 Wiley‐Liss, Inc.
Effects of quercetin and chrysin on 2,3,7,8‐tetrachlorodibenzo‐p‐dioxin induced hepatotoxicity in rats
Authors: Ciftci Osman , Vardi Nigar , Ozdemir Ilknur 
Published: May 2011

AbstractThe objective of current study is to investigate the effects of the administration of chrysin (CH) and quercetin (Q) on rat liver in which oxidative and histological damage had been induced by 2,3,7,8‐tetrachlorodibenzo‐p‐dioxin (TCDD). Rats were randomly divided into six equal groups. TCDD was orally administered at the dose of 2 μg/kg/week, and Q and CH were orally administered at the doses of 20 mg/kg day and 50 mg/kg/day, respectively, by gavages dissolved in corn oil. The liver samples to be analyzed for the determination of oxidative and histological alternations were taken from rats at 60 days. The results indicated that although 2,3,7,8‐TCDD significantly induced (P ≤ 0.01) lipid peroxidation (increase of MDA levels), it positively affected oxidant/antioxidant system (a decline in the levels of GSH, CAT, GSH‐Px, and CuZn‐SOD) in rats significantly. The histological changes observed in the liver correlated with the biochemical findings. However, these effects of TCDD on oxidative and histological changes were eliminated by Q and CH treatment. In conclusion, TCDD caused an adverse effect on rat's liver. When Q and CH were given together with TCDD, they prevented hepatotoxicty induced by TCDD. Thus, it is thought that Q and CH may be useful as a new category of anti‐TCDD toxicity agent. © 2011 Wiley Periodicals, Inc. Environ Toxicol, 2013.
Effects of trifluralin on the mouse ovary
Authors: Cecconi Sandra , Rossi Gianna , Carta Gaspare , Di Luigi Gianluca , Cellini Valerio , Canipari Rita , Buccione Roberto 
Published: May 2011

AbstractTrifluralin, a herbicide used to protect many arable and horticultural crops, was evaluated for its potential toxicity on the mammalian ovary. To this end, adult female mice were fed or not (control) with a trifluralin‐enriched diet (150 mg/kg body weight/day) during gestation and lactation. After weaning, 3‐week‐old female mice from either trifluralin‐treated or control groups were used to evaluate whether the exposure to this herbicide in utero and during lactation could induce stress responses in the ovary. It was found that trifluralin exposure caused a significantly higher level of p53, but not of pRb, in the whole ovary, and in particular in granulosa cells. TUNEL staining showed that herbicide treatment did not increase the apoptotic index of the somatic compartment. Also oocyte fertilizability was unaffected, as metaphase II oocytes retrieved from treated mice were capable of forming male and female pronuclei after in vitro fertilization as control mice. However, trifluralin determined a slightly higher number of oocytes with cytoplasmic degeneration compared with control animals. In conclusion, our results suggest that exposure to a low trifluralin dose during pregnancy and lactation does not impair oocyte quality, but can induce a stress response in ovarian somatic cells. © 2011 Wiley Periodicals, Inc. Environ Toxicol, 2013.
Toxicologic and immunologic effects of perinatal exposure to the brominated diphenyl ether (BDE) mixture DE‐71 in the Sprague‐Dawley rat
Authors: Bondy Genevieve S. , Lefebvre David E. , Aziz Syed , Cherry Wendy , Coady Laurie , MacLellan Ellen , Armstrong Cheryl , Barker Michael , Cooke Gerard , Gaertner Dean , Arnold Doug L. , Mehta Rekha , Rowsell Paul R. 
Published: May 2011

AbstractBrominated diphenyl ethers (BDEs) are persistent environmental contaminants found in human blood, tissues, and milk. To assess the impact of the commercial BDE mixture DE‐71 on the developing immune system in relation to hepatic and thyroid changes, adult (F0) rats were exposed to DE‐71 by gavage at doses of 0, 0.5, 5, or 25 mg/kg body weight (bw)/d for 21 weeks. F0 rats were bred and exposure continued through gestation, lactation and postweaning. F1 pups were weaned and exposed to DE‐71 by gavage from postnatal day (PND) 22 to 42. On PND 42, half of the F1 rats were assessed for toxicologic changes. The remaining F1 rats were challenged with the T‐dependent antigen keyhole limpet hemocyanin (KLH) and immune function was assessed on PND 56. Dose‐dependent increases in total BDE concentrations were detected in the liver and adipose of all F0 and F1 rats. In F0 rats, increased liver weight, hepatocellular hypertrophy, and decreased serum thyroxine (T4) were characteristic of DE‐71 exposure. In F1 rats perinatal DE‐71 exposure caused a nondose‐dependent increase in body weight and dose‐dependent increases in liver weight and hepatocellular hypertrophy. Serum T3 and T4 levels were decreased. In spleen from DE‐71 exposed rats the area occupied by B cells declined while the area occupied by T cells increased; however, cellular and humoral immune responses to KLH challenge were not altered. Thus hepatic and thyroid changes in rats exposed perinatally to DE‐71 were associated with altered splenic lymphocyte populations, an effect which has been linked to hypothyroidism. © 2011 Wiley Periodicals, Inc. Environ Toxicol, 2013.
Metiram‐induced nephrotoxicity in albino mice: Effect of licorice aqueous extract
Authors: Sakr Saber , EL‐Kenawy Ayman , EL‐Sahra Doaa 
Published: May 2011

AbstractThe present study was designed to estimate the effect of aqueous extract of licorice on metiram toxicity in mice. Treating mice with metiram at a dose level of [1/2] LD50 daily for 3 weeks induced many histological changes in the kidney cortex. The renal tubules lost their characteristic appearance and their lining epithelial cells were degenerated. The glomeruli were atrophied and the renal blood vessels were congested. The intertubular spaces infiltrated by inflammatory leukocytic cells. Metiram caused an increase in proliferating cell nuclear antigen (PCNA) expression in nuclei of tubular epithelial cells. Metiram also caused marked elevation in serum creatinine and blood urea nitrogen. Treating animals with metiram and licorice aqueous extract led to an improvement, in both biochemical and histopathological alterations. These results proved that licorice had an ameliorative effect against kidney injury induced by metiram and this effect may be attributed to its antioxidant activity. © 2011 Wiley Periodicals, Inc. Environ Toxicol, 2013.
Coding‐aware routing and scheduling in WiMAX‐based mesh networks: a cross‐layer design approach
Authors: El‐Najjar Jad , Assi Chadi , Jaumard Brigitte 
Published: May 2011

ABSTRACTIn this paper, we propose a cross‐layer design framework for the joint problem of coding‐aware routing and scheduling in WiMAX‐based mesh networks with unicast sessions. The model attempts to maximize the system throughput by exploiting opportunistic coding opportunities through appropriate routing and by achieving efficient spectrum reuse through appropriate link scheduling. We assume centralized scheduling at the base station and focus on minimizing the total schedule length to satisfy a certain traffic demand. Minimizing the schedule length is equivalent to maximizing the system throughput. We present a linear programming optimization model for the joint problem, which relies on the enumeration of all possible schedules. Given its complexity, we decompose the problem using a column generation approach. Our numerical results show that significant gains may be achieved when network coding is incorporated into the design. We compare the performance with that of a joint coding‐oblivious model with and without transmission power control. Copyright © 2011 John Wiley & Sons, Ltd.
Cooperative communications with relay selection for wireless networks: design issues and applications
Authors: Liang Xuedong , Chen Min , Balasingham Ilangko , Leung Victor C.M. 
Published: May 2011

ABSTRACTRelay selection schemes for cooperative communications to achieve full cooperative diversity gains while maintaining spectral and energy efficiency have been extensively studied in a recent research. These schemes select only the best relay from multiple relaying candidates to cooperate with a communication link. In the present paper, we reviewed recently proposed cooperative communication protocols that integrate with relay selection mechanisms. The key design issues for relay selection mechanisms, for example, relaying candidate selection, optimal relay assignment, and cooperative transmission, were identified. We further discussed the challenges of optimal relay assignment in multi‐hop wireless sensor networks and presented the potential applications of cooperative communications with a relay selection in such networks. Future research directions were outlined, for example, the issues of service differentiation and system fairness in cooperative communication systems and the joint use of game theory and adaptive learning techniques in relaying candidate selection and optimal‐relay assignment mechanisms for efficient allocation of network resources. Copyright © 2011 John Wiley & Sons, Ltd.
EPA or DHA Supplementation Increases Triacylglycerol, but not Phospholipid, Levels in Isolated Rat Cardiomyocytes
Authors: Righi Valeria , Di Nunzio Mattia , Danesi Francesca , Schenetti Luisa , Mucci Adele , Boschetti Elisa , Biagi Pierluigi , Bonora Sergio , Tugnoli Vitaliano , Bordoni Alessandra 
Published: May 2011

AbstractIt is well recognized that a high dietary intake of long‐chain polyunsaturated fatty acids (LC‐PUFA) has profound benefits on health and prevention of chronic diseases. In particular, in recent years there has been a dramatic surge of interest in the health effects of n‐3 LC‐PUFA derived from fish, eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids. Notwithstanding, the metabolic fate and the effects of these fatty acids once inside the cell has seldom been comprehensively investigated. Using cultured neonatal rat cardiomyocytes as model system we have investigated for the first time, by means of high‐resolution magic‐angle spinning nuclear magnetic resonance (HR‐MAS NMR) spectroscopy in combination with gas chromatography (GC), the modification occurring in the cell lipid environment after EPA and DHA supplementation. The most important difference between control and n‐3 LC‐PUFA‐supplemented cardiomyocytes highlighted by HR‐MAS NMR spectroscopy is the increase of signals from mobile lipids, identified as triacylglycerols (TAG). The observed increase of mobile TAG is a metabolic response to n‐3 LC‐PUFA supplementation, which leads to an increased lipid storage. The sequestration of mobile lipids in lipid bodies provides a deposit of stored energy that can be accessed in a regulated fashion according to metabolic need. Interestingly, while n‐3 LC‐PUFA supplementation to neonatal rat cardiomyocytes causes a huge variation in the cell lipid environment, it does not induce detectable modifications in water‐soluble metabolites, suggesting negligible interference with normal metabolic processes.
Dry Fractionation and Crystallization Kinetics of High‐Oleic High‐Stearic Sunflower Oil
Authors: Bootello Miguel A. , Garcés Rafael , Martínez‐Force Enrique , Salas Joaquín J. 
Published: May 2011

AbstractFractionation of fats and oils makes it possible to generate products with specific properties from natural fats that contain a variety of triacylglycerol (TAG) species. High‐oleic high‐stearic (HOHS) sunflower oils contain high levels of saturated fatty acids, mainly stearate, on a high‐oleic background. Accordingly, HOHS oils could be a source of disaturated TAGs appropriate for cocoa butter equivalent formulations. We examined the kinetics of HOHS oil crystallization, paying special attention to the influence of crystal seeding and temperature on the process and the composition of the final fractions. This oil was fractionated at 18 °C, and seeding increased the amount of disaturated TAGs recovered in the precipitate from 23% to up to 30%. The experimental data collected were fitted using the models of Gompertz and Avrami to study how well these models fitted the data and their utility in predicting the progress of crystallization. At seeding additions above 0.25% there was a change in the crystallization mechanism that improved the process of fractionation. The effect of temperature was also studied, showing important increases in the maximum rates of crystallization when fractionations were carried out at lower temperatures. Finally, the melting profiles of the fractions enriched in saturated fatty acids were studied, showing amounts of solids intermediate between the initial oil and cocoa butter.
The Endosperm Morphology of Rice and its Wild Relatives as Observed by Scanning Electron Microscopy
Authors: Kasem S. , Waters D. L. E. , Rice N. F. , Shapter F. M. , Henry R. J. 
Published: May 2011

Abstract
While cultivated rice, Oryza sativa, is arguably the world’s most important cereal crop, there is little comparative morphological information available for the grain of rice wild relatives. In this study, the endosperm of 16 rice wild relatives were compared to O. sativa subspecies indica and O. sativa subspecies japonica using scanning electron microscopy. Although the aleurone, starch granules, protein bodies and endosperm cell shapes of the cultivated and non-cultivated species were similar, several differences were observed. The starch granules of some wild species had internal channels that have not been reported in cultivated rice. Oryza longiglumis, Microlaena stipoides and Potamophila parviflora, had an aleurone that was only one-cell thick in contrast to the multiple cell layers observed in the aleurone of the remaining Oryza species. The similarity of the endosperm morphology of undomesticated species with cultivated rice suggests that some wild species may have similar functional properties. Obtaining a better understanding of the wild rice species grain ultrastructure will assist in identifying potential opportunities for development of these wild species as new cultivated crops or for their inclusion in plant improvement programmes.