bluuebunny/crossref_metadata_2025_split huggingface dataset:
A new ‘event‐on‐demand’ synthesizer of rain attenuation time series at Ku‐, Ka‐ and Q/V‐bands
Authors: Carrie Guillaume , Lacoste Frédéric , Castanet Laurent 
Published: November 2009

AbstractTo develop and test real‐time fade mitigation techniques control algorithms, propagation time series are needed. An alternative to using real data collected from propagation experiments is to generate typical fading time‐series making use of climatological characteristics as well as geometrical and radio‐electrical parameters of the link. The objective of this paper is to present a rain attenuation time‐series synthesizer and able to generate events on demand. The model is based on an enhanced version of the Maseng–Bakken stochastic model. In the first part of this paper, the basic principles of the enhanced Maseng–Bakken model are recalled and the parameterization of this channel model is discussed for temperate European climates. Then, the theoretical bases of the Lacoste–Carrie ‘event‐on‐demand’ model and its validation constitute the second part of this paper. The enhanced Maseng–Bakken model is fully stochastic, whereas the Lacoste‐Carrie ‘event‐on‐demand’ one offers the possibility to command the maximum attenuation level and the duration of the synthesized event. Copyright © 2009 John Wiley & Sons, Ltd.
Network patterns and competitive advantage before the emergence of a dominant design
Authors: Soh Pek‐Hooi 
Published: November 2009

AbstractThis study examines the performance implications of the alliance networks of 49 firms that competed for two technology standards in the U.S. local area network industry from 1989 to 1996. During the race to define a dominant design, individual firms attract the suppliers of complements by building alliance networks to favor the firms' preferred technology standard. Controlling for the number of suppliers in each technology standard community and the extent of technical progress achieved by individual firms, the panel data analysis shows that central firms with high ego network density, coupled with a strategic intent to acquire and share knowledge broadly within the technological community, achieve better innovation performance. The size of the technological community and some random events in the early formation of the industry do not provide a sufficient explanation of how these firms gain the diverse support of suppliers or enhance their competitive advantage. By demonstrating the independent and contingent effects of alliance network properties, this study explains how network patterns might enhance or limit the benefits of alliance networks when focal firms embrace different innovation strategies. Copyright © 2009 John Wiley & Sons, Ltd.
Value creation in innovation ecosystems: how the structure of technological interdependence affects firm performance in new technology generations
Authors: Adner Ron , Kapoor Rahul 
Published: November 2009

AbstractThe success of an innovating firm often depends on the efforts of other innovators in its environment. How do the challenges faced by external innovators affect the focal firm's outcomes? To address this question we first characterize the external environment according to the structure of interdependence. We follow the flow of inputs and outputs in the ecosystem to distinguish between upstream components that are bundled by the focal firm, and downstream complements that are bundled by the firm's customers. We hypothesize that the effects of external innovation challenges depend not only on their magnitude, but also on their location in the ecosystem relative to the focal firm. We identify a key asymmetry that results from the location of challenges relative to a focal firm—greater upstream innovation challenges in components enhance the benefits that accrue to technology leaders, while greater downstream innovation challenges in complements erode these benefits. We further propose that the effectiveness of vertical integration as a strategy to manage ecosystem interdependence increases over the course of the technology life cycle. We explore these arguments in the context of the global semiconductor lithography equipment industry from its emergence in 1962 to 2005 across nine distinct technology generations. We find strong empirical support for our framework. Copyright © 2009 John Wiley & Sons, Ltd.
Vorhersage duktilen Festigkeitsversagens von Stahlbauteilen mit Hilfe schädigungsmechanischer Methoden
Authors: Feldmann Markus , Schäfer Dirk , Eichler Björn 
Published: November 2009

AbstractNachweise im Grenzzustand der Tragfähigkeit setzen ausreichende Duktilität voraus. Insbesondere bei der Bemessung nach dem Traglastverfahren, im Erdbebenfall, bei Explosion oder Anprall werden die plastischen Reserven von Konstruktionen gefordert, und es muss sichergestellt werden, dass ausreichendes Verformungsvermögen vorliegt und kein sprödes Versagen auftritt. Zur Absicherung der Nachweismodelle werden im Regelfall Versuche bei Raumtemperatur durchgeführt und entsprechende Sicherheitselemente abgeleitet.Im Rahmen dieses Aufsatzes werden schädigungsmechanische Methoden vorgestellt, die es ermöglichen, das duktile Versagensverhalten von Stahlbauteilen vorherzusagen. Basierend auf einem Grenzzustand zwischen der lokalen plastischen Dehnungsanforderung, die sich aus der globalen Belastung, dem Detail und dem verwendeten Stahl ergibt, und dem lokalem plastischem Dehnungswiderstand, der sich in Abhängigkeit von Stahlsorte, Temperatur und Dehnrate quantifizieren lässt, können in Zukunft realistische Kriterien für die Werkstoffauswahl in der Hochlage bereitgestellt werden. Der nachfolgende Aufsatz zeigt Auszüge aus den Ergebnissen eines Europäischen Forschungsvorhabens [1] zur Bestimmung eines Hochlagenkriteriums für den Stahlbau.Prediction of ductile failure of steel structures by damage mechanics.For the verification in the ultimate limit state sufficient ductility is assumed. Especially in plastic design and for seismic events, explosion or impact it has to be ensured, that the structure shows sufficient deformation capacity and the material provides enough ductility in the upper shelf region and brittle fracture is excluded. To validate the verification procedures tests are performed at room temperature and corresponding safety elements are derived.Within this article methods based on damage mechanics are presented which allow for an estimation of the ductile fracture behaviour of steel structures in the upper shelf. By this means extensive testing may be supplemented or replaced to some extent. Based upon a limit state between local plastic strain requirements arising from loading situation, detail and steel grade, and local plastic strain resistances given in dependency of the material, temperature and strain rate realistic criteria for the selection of material in the upper shelf will be derived.In the following excerpts of the results of a European project [1] are shown which deals with the derivation of an upper shelf criterion for steel structures.
Instandsetzung der historischen Kettenbrücke Nassau
Authors: Albrecht Gert , Frießem Heinrich , Langen Thiemo 
Published: November 2009

AbstractDie Kettenbrücke Nassau über die Lahn von dem Ortskern der Stadt Nassau zum Stadtteil Bergnassau ist in jeder Hinsicht ein außergewöhnliches Bauwerk. Die Brückengeschichte reicht weit in das 19. Jahrhundert zurück. Das Stadtbild sowie das Landschaftsbild des Lahntals werden seit 1830 – nun in dritter Generation – nachhaltig von dieser Brücke geprägt. Es ist eine charakteristische Brücke mit besonderer verkehrstechnischer Bedeutung. Sie verbindet Lahnstein und Wiesbaden und befindet sich in zweiter Generation 1927 auf der historischen Bäderstraße. Der Neubau in dritter Generation 2005 fügt sich hier nahtlos ein.Restoration of the historical chain‐suspension bridge Nassau, Germany.The old chain‐suspension bridge over the river Lahn from the main city of Nassau to the part Bergnassau is an extraordinary building. The history of the bridge started in the year 1830 (first Generation). This bridge represented the view of the city Nassau and the landscape of the valley of the river Lahn. It is a characteristically bridge with high importance for traffic, because the cities of Lahnstein and Wiesbaden will be included (second Generation, 1927). The new bridge (third Generation, 2005) is also integrated in the view of the Nassau‐City.
Historische Stützen aus Grauguss – Tragsicherheitsnachweise und Ertüchtigung
Authors: Heyde Stefan , Lindner Joachim 
Published: November 2009

AbstractDie Pflege und Rekonstruktion von historischen Gebäuden ist eine wesentliche Aufgabe des Bauingenieurwesens und zudem von großem wirtschaftlichen Interesse. In Gebäuden aus der Zeit um 1900 sind dabei oft gusseiserne Stützen anzutreffen. Ihre Tragfähigkeit haben diese Bauteile für die bestehenden Lasten längst unter Beweis gestellt; eine Umnutzung ist jedoch in der Regel mit vergrößerten Lasten verbunden, und der Nachweis der Tragfähigkeit muss entsprechend den geltenden Sicherheitsanforderungen erneut erbracht werden. In den aktuellen Normen DIN 18800‐2 [5] und DIN EN 1993‐1‐1 [8] sind historische Baustoffe aber nicht mehr enthalten, so dass derzeit kein gültiges Nachweisverfahren für diese Bauteile existiert. Es wird daher ein Verfahren vorgestellt, mit dem im Sinne eines Ersatzstabverfahrens entsprechend den aktuellen Normen der Stabilitätsnachweis für historische Stützen unter zentrischer und exzentrischer Belastung geführt werden kann. Darüberhinaus wird die Frage diskutiert, inwieweit historische Stützen durch Verfüllen mit selbstverdichtendem Beton ertüchtigt werden können.Historic grey cast‐iron columns – analysis of structural safety and upgrade.Cast‐iron columns were used in many industrial and public buildings from round 1900. During renovation the preservation of these historic columns is a current tendency of public authorities as well as an economical interest. Because of the special material properties the strength of these columns cannot be estimated on the base of present design codes for steel structures e. g. DIN EN 1993‐1‐1 (EC 3) [8] or the German stability code DIN 18800‐2 [5].Thus a proposal for the design check will be presented for centrically and excentrically loaded columns on the basis of actual interaction formulae. Furthermore the strengthening of cast‐iron columns by filling with self compacting concrete will be discussed.
Das schwebende Dach – Die neue Hauptpforte der Firma Trumpf in Ditzingen
Authors: Sobek Werner , Winterstetter Thomas , Hinz Holger 
Published: November 2009

AbstractDie Firma Trumpf ist Weltmarktführer für Laserschneide‐ und ‐schweißanlagen. Der Hauptsitz der Firma befindet sich in Ditzingen bei Stuttgart. Um den Zugang zum stetig wachsenden Betriebsgelände neu zu fassen, wurde im Eingangsbereich ein neues Pfortengebäude errichtet, das durch seine Formensprache, seine Transparenz und seinen technischen Standard jedem Besucher bereits bei Betreten des Firmengeländes die Kompetenz und Philosophie des Unternehmens anschaulich vermitteln soll.The floating roof – The new gatehouse of the company Trumpf in Ditzingen, Germany.Trumpf is a world market leader for laser‐cutting and laser‐welding machines. The headquarters of the company are situated at Ditzingen near Stuttgart. In order to make the entrance to the continuously growing premises more attractive, a new gatehouse was constructed. The gatehouse is to communicate the company's transparency, technological know‐how and technical standards even before the visitors enter the premises themselves. Particular features of the gatehouse are its thin roof cantilevering by about 20?m and the highly transparent façade.
Notch Promotes Radioresistance of Glioma Stem Cells
Authors: Wang Jialiang , Wakeman Timothy P. , Lathia Justin D. , Hjelmeland Anita B. , Wang Xiao-Fan , White Rebekah R. , Rich Jeremy N. , Sullenger Bruce A. 
Published: November 2009

Abstract
Radiotherapy represents the most effective nonsurgical treatments for gliomas. However, gliomas are highly radioresistant and recurrence is nearly universal. Results from our laboratory and other groups suggest that cancer stem cells contribute to radioresistance in gliomas and breast cancers. The Notch pathway is critically implicated in stem cell fate determination and cancer. In this study, we show that inhibition of Notch pathway with γ-secretase inhibitors (GSIs) renders the glioma stem cells more sensitive to radiation at clinically relevant doses. GSIs enhance radiation-induced cell death and impair clonogenic survival of glioma stem cells but not non-stem glioma cells. Expression of the constitutively active intracellular domains of Notch1 or Notch2 protect glioma stem cells against radiation. Notch inhibition with GSIs does not alter the DNA damage response of glioma stem cells after radiation but rather reduces Akt activity and Mcl-1 levels. Finally, knockdown of Notch1 or Notch2 sensitizes glioma stem cells to radiation and impairs xenograft tumor formation. Taken together, our results suggest a critical role of Notch signaling to regulate radioresistance of glioma stem cells. Inhibition of Notch signaling holds promise to improve the efficiency of current radiotherapy in glioma treatment.
To be or not to be? Discursive resources for (Dis‐)identifying with science‐related careers
Authors: Hsu Pei‐Ling , Roth Wolff‐Michael , Marshall Anne , Guenette Francis 
Published: November 2009

AbstractOne of the main objectives of many science educators is to enroll students into science majors and careers. Researchers have investigated students' views of science in terms of factors and influences that guide students to choose science as a career. However, few investigations exist that have studied the forms of language culture makes available for articulating possible careers generally or the ways of grounding (justifying) these possibilities particularly. The purpose of this study is to investigate ways of using language for supporting justifications of career choices in an interview situation. Thirteen high school biology students were interviewed about their career choices. Drawing on discursive psychology as theory and method, we identify four interpretative repertoires that are deployed during the interviews: the (a) formative, (b) performative, (c) consequent, and (d) potential repertoires. These interpretative repertoires do not merely characterize the discourse about different science‐related professions but in fact co‐articulate different science‐related identities. © 2009 Wiley Periodicals, Inc. J Res Sci Teach 46: 1114–1136, 2009
Stabilization and Riesz basis property of two serially connected Timoshenko beams system
Authors: Han Z.J. , Xu G.Q. 
Published: November 2009

AbstractIn this paper we study the stabilization problem and Riesz basis property of two serially connected Timoshenko beams whose left end is simply supported and the right end is free. Suppose that the displacement and bending moments of the beams at the interior node are continuous, but the shearing force and rotational angle are discontinuous. We design the compensator and feedback controllers at the left end and the interior node of the beams so as to derive the beams back to their equilibrium position. We prove that this closed loop system is well‐posed and asymptotically stable. By the spectral analysis, we also show that its root vectors form a Riesz basis with parentheses for the state space. Hence the spectrum determined growth condition holds. Further, we show that this system is not exponentially stable. Finally, we give a numerical simulation of this kind of closed loop system to support our results.
Successful ACL reconstruction with a variant of the pes anserinus
Authors: Patel Shelain , Trehan Ravi K. , Railton Gil T. 
Published: November 2009

AbstractAn anatomical variant of the pes anserinus encountered during anterior cruciate ligament reconstructive surgery which has not been previously described is discussed. During routine harvesting, the sartorius fascia was incised and the semitendinosus and gracilis tendons were identified. At the distal portion, it was noted that each tendon gave off an additional tendinous slip. The slip from the semitendinosus tendon had attached to the gracilis tendon and vice versa, thereby creating a double pes anserinus. This variant was used to construct the graft, and at 1 year review the patient had returned to full sporting activities with no complications encountered.
Facile Synthesis and Tensile Behavior of TiO2 One-Dimensional Nanostructures
Authors: Amin Syed S. , Li Shu-you , Wu Xiaoxia , Ding Weiqiang , Xu Terry T. 
Published: November 2009

Abstract
High-yield synthesis of TiO2 one-dimensional (1D) nanostructures was realized by a simple annealing of Ni-coated Ti grids in an argon atmosphere at 950 °C and 760 torr. The as-synthesized 1D nanostructures were single crystalline rutile TiO2 with the preferred growth direction close to [210]. The growth of these nanostructures was enhanced by using catalytic materials, higher reaction temperature, and longer reaction time. Nanoscale tensile testing performed on individual 1D nanostructures showed that the nanostructures appeared to fracture in a brittle manner. The measured Young’s modulus and fracture strength are ~56.3 and 1.4 GPa, respectively.
Fabrication of a Highly Sensitive Chemical Sensor Based on ZnO Nanorod Arrays
Authors: Park JaeYoung , Choi Sun-Woo , Kim SangSub 
Published: November 2009

Abstract
We report a novel method for fabricating a highly sensitive chemical sensor based on a ZnO nanorod array that is epitaxially grown on a Pt-coated Si substrate, with a top–top electrode configuration. To practically test the device, its O2 and NO2 sensing properties were investigated. The gas sensing properties of this type of device suggest that the approach is promising for the fabrication of sensitive and reliable nanorod chemical sensors.
Antifungal Activity of Leaf Essential Oil and Extracts of Metasequoia glyptostroboides Miki ex Hu
Authors: Bajpai Vivek K. , Kang Sun Chul 
Published: November 2009

AbstractPlant diseases constitute an emerging threat to global food security. Many of the currently available antifungal agents for agriculture are highly toxic and nonbiodegradable and cause extensive environmental pollution. Moreover, an increasing number of phytopathogens are developing resistance to them. Therefore, the aim of this study was to assess the antifungal efficacy of the leaf essential oil and the leaf extracts of Metasequoia glyptostroboides against Fusarium oxysporum, Fusarium solani, Phytophthora capsici, Colletotrichum capsici, Sclerotinia sclerotiorum, Botrytis cinerea and Rhizoctonia solani. The oil (1,000 μg/disc) and the extracts (1,500 μg/disc) revealed a remarkable antifungal effect against the tested plant pathogenic fungi with a radial growth inhibition percentage of 41.3–66.3% and 13.4–54.4%, respectively along with their respective MIC values ranging from 62.5 to 1,000 μg/ml and 500–4,000 μg/ml. The oil had a strong detrimental effect on spore germination of all the tested plant pathogens along with the concentration as well as time‐dependent kinetic inhibition of Botrytis cinerea. Also, the oil exhibited a potent in vivo antifungal effect against Phytophthora capsici on greenhouse grown pepper plants. The results of this study indicate that the oil and extracts of M. glyptostroboides leaves could become natural alternatives to synthetic fungicides to control certain important plant fungal diseases.
Stakeholder pressure and the adoption of environmental practices: The mediating effect of training
Authors: Sarkis Joseph , Gonzalez‐Torre Pilar , Adenso‐Diaz Belarmino 
Published: November 2009

AbstractThe influence of stakeholder pressure on the adoption of environmental practices has been established in the literature. In this paper we posit that these direct effects are further mediated, causally, by the level of training in companies. Theoretically, this relationship is supported by the relationship between institutional theory (stakeholder pressure) and the dimensions of dynamic capabilities in resource‐based theory. We investigate this relationship within the Spanish automotive industry. The theoretical contribution of this paper focuses on further supporting the relationship between stakeholder and resource‐based theory as complementary theoretical frameworks. The practical implications focus on whether or not training should be integrated in order to help in the adoption of particular environmental practices, which in this study are represented by environmentally oriented reverse logistics practices.
Implicit and explicit affective associations towards cannabis use in patients with recent-onset schizophrenia and healthy controls
Authors: Dekker N. , Smeerdijk A. M. , Wiers R. W. , Duits J. H. , van Gelder G. , Houben K. , Schippers G. , Linszen D. H. , de Haan L. 
Published: November 2009

BackgroundCannabis use is common in patients with recent-onset schizophrenia and this is associated with poor disease outcome. More insight in the cognitive-motivational processes related to cannabis use in schizophrenia may inform treatment strategies. The present study is the first known to compare implicit and explicit cannabis associations in individuals with and without psychotic disorder.MethodParticipants consisted of 70 patients with recent-onset psychotic disorder and 61 healthy controls with various levels of cannabis use. Three Single-Category Implicit Association Tests (SC-IAT) were used to assess ‘relaxed’, ‘active’ and ‘negative’ implicit associations towards cannabis use. Explicit expectancies of cannabis use were assessed with a questionnaire using the same words as the SC-IAT.ResultsThere were no differences in implicit associations between patients and controls; however, patients scored significantly higher on explicit negative affect expectancies than controls. Both groups demonstrated strong negative implicit associations towards cannabis use. Explicit relaxed expectancies were the strongest predictors of cannabis use and craving. There was a trend for implicit active associations to predict craving.ConclusionsThe findings indicate that patients suffering from schizophrenia have associations towards cannabis similar to controls, but they have stronger negative explicit cannabis associations. The strong negative implicit associations towards cannabis could imply that users of cannabis engage in a behaviour they do not implicitly like. Explicit relaxing expectancies of cannabis might be an important mediator in the continuation of cannabis use in patients and controls.