bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dynamic MicroRNA Gene Transcription and Processing during T Cell Development
Authors: Kirigin Francis F. , Lindstedt Kenneth , Sellars Maclean , Ciofani Maria , Low Siao Li , Jones Lachlan , Bell Fiona , Pauli Florencia , Bonneau Richard , Myers Richard M. , Littman Dan R. , Chong Mark M. W. 
Published: March 2012

Abstract
By disrupting microRNA (miRNA) biogenesis, we previously showed that this pathway is critical for the differentiation and function of T cells. Although various cloning studies have shown that many miRNAs are expressed during T cell development, and in a dynamic manner, it was unclear how comprehensive these earlier analyses were. We therefore decided to profile miRNA expression by next generation sequencing. Furthermore, we profiled miRNA expression starting from the hematopoietic stem cell. This analysis revealed that miRNA expression during T cell development is extremely dynamic, with 645 miRNAs sequenced, and the expression of some varying by as much as 3 orders of magnitude. Furthermore, changes in precursor processing led to altered mature miRNA sequences. We also analyzed the structures of the primary miRNA transcripts expressed in T cells and found that many were extremely long. The longest was pri–mir-29b-1/29a at ∼168 kb. All the long pri-miRNAs also displayed extensive splicing. Our findings indicate that miRNA expression during T cell development is both a highly dynamic and a highly regulated process.
Follicular Helper NKT Cells Induce Limited B Cell Responses and Germinal Center Formation in the Absence of CD4+ T Cell Help
Authors: Tonti Elena , Fedeli Maya , Napolitano Anna , Iannacone Matteo , von Andrian Ulrich H. , Guidotti Luca G. , Abrignani Sergio , Casorati Giulia , Dellabona Paolo 
Published: March 2012

Abstract
B cells require MHC class II (MHC II)-restricted cognate help and CD40 engagement by CD4+ T follicular helper (TFH) cells to form germinal centers and long-lasting Ab responses. Invariant NKT (iNKT) cells are innate-like lymphocytes that jumpstart the adaptive immune response when activated by the CD1d-restricted lipid α-galactosylceramide (αGalCer). We previously observed that immunization of mice lacking CD4+ T cells (MHC II−/−) elicits specific IgG responses only when protein Ags are mixed with αGalCer. In this study, we investigated the mechanisms underpinning this observation. We find that induction of Ag-specific Ab responses in MHC II−/− mice upon immunization with protein Ags mixed with αGalCer requires CD1d expression and CD40 engagement on B cells, suggesting that iNKT cells provide CD1d-restricted cognate help for B cells. Remarkably, splenic iNKT cells from immunized MHC II−/− mice display a typical CXCR5hiprogrammed death-1hiICOShiBcl-6hi TFH phenotype and induce germinal centers. The specific IgG response induced in MHC II−/− mice has shorter duration than that developing in CD4-competent animals, suggesting that iNKTFH cells preferentially induce transient rather than long-lived Ab responses. Together, these results suggest that iNKT cells can be co-opted into the follicular helper function, yet iNKTFH and CD4+ TFH cells display distinct helper features, consistent with the notion that these two cell subsets play nonredundant functions throughout immune responses.
Oligocrystalline Shape Memory Alloys
Authors: Ueland Stian M. , Chen Ying , Schuh Christopher A. 
Published: March 2012

AbstractCopper‐based shape memory alloys (SMAs) exhibit excellent shape memory properties in single crystalline form. However, when they are polycrystalline, their shape memory properties are severely compromised by brittle fracture arising from transformation strain incompatibility at grain boundaries and triple junctions. Oligocrystalline shape memory alloys (oSMAs) are microstructurally designed SMA structures in which the total surface area exceeds the total grain boundary area, and triple junctions can even be completely absent. Here it is shown how an oligocrystalline structure provides a means of achieving single crystal‐like SMA properties without being limited by constraints of single crystal processing. Additionally, the formation of oSMAs typically involves the reduction of the size scale of specimens, and sample size effects begin to emerge. Recent findings on a size effect on the martensitic transformation in oSMAs are compared and a new regime of heat transfer associated with the transformation heat evolution in these alloys is discussed. New results on unassisted two‐way shape memory and the effect of loading rate in oSMAs are also reported.
Charge Formation in Pentacene Layers During Solar‐Cell Fabrication: Direct Observation by Electron Spin Resonance
Authors: Marumoto Kazuhiro , Fujimori Takuya , Ito Masaaki , Mori Tatsuo 
Published: March 2012

AbstractMicroscopic characterization of charge carriers in solar cells is useful for high‐performance cell fabrication because the formation and accumulation of charges in cells greatly affect the device performance. Electron spin resonance (ESR) is suitable for such characterization because it can directly observe charge carriers with spins in these cells. In this work, the ESR method is applied to organic thin‐film solar cells to investigate charge formation in such devices. Heterojunction cells of indium tin oxide (ITO)/poly(3,4‐ethylenedioxythiophene):poly(4‐styrenesulfonate) (PEDOT:PSS)/pentacene/C60/bathocuproine (BCP)/Al are investigated. Clear ESR signals are observed by inserting a typical PEDOT:PSS hole buffer layer. From analysis of the dependence of the ESR characteristics on the external magnetic field direction, the bias voltage, and the duration of solar‐simulated irradiation, the charges (mobile holes) in pentacene layers are successfully identified and it can be deduced that these holes are formed at the PEDOT:PSS/pentacene interface during device fabrication. This ESR analysis provides useful knowledge for understanding device operation and improving device performance at the microscopic level.
On‐line estimation of glucose and biomass concentration in batch fermentation process using particle filter with constraint
Authors: Zhao Zhonggai , Shao Xinguang , Huang Biao , Liu Fei 
Published: March 2012

ABSTRACTIn most of fermentation processes, the substrate and biomass concentrations greatly influence the yield of the targeted product. In this paper, considering the nonlinear and non‐Gaussian nature of the fermentation processes, the particle filter method is introduced to estimate the substrate and biomass states, and an algorithm integrating optimization strategy with resampling is proposed to deal with constraints on states. The proposed approach investigates the constraint directly on the estimated value rather than on particles. If the estimation violates constraints, the optimal estimation is firstly obtained by the optimization approach, and then, the resampling and optimization strategy are iteratively used to randomly draw a particle each time among the violated posterior particles and project it onto the feasible region. The resampling and optimization steps are iterated until the state estimation, derived from posterior particles, reaches better performance than that through previous optimization formulation or all the violated posterior particles have been projected onto the feasible region. Compared with the other previous optimization approaches, the proposed method results in a better balance between reducing the on‐line computation load and obtaining more effective posterior particles. © 2012 Curtin University of Technology and John Wiley & Sons, Ltd.
Naphthyl and Thienyl Units as Bridges for Metal‐Free Dye‐Sensitized Solar Cells
Authors: Chen Yung‐Chung , Chen Yo‐Hua , Chou Hsien‐Hsin , Chaurasia Sumit , Wen Yuh S. , . Lin Jiann T , Yao Ching‐Fa 
Published: March 2012

AbstractA series of new organic dyes, comprising a naphthyl moiety as a π‐conjugated bridge, different amines as donors, and a cyanoacrylic acid group as an electron acceptor and anchoring group, have been designed and synthesized for applications in dye‐sensitized solar cells (DSSCs). One of the compounds was also characterized by single‐crystal X‐ray structural analysis. All of the dyes exhibited maximum absorptions in the range of 371–441 nm. The short‐circuit photocurrent density, open‐circuit voltage, and fill factor (FF) values of the devices are in the range of 6.13–10.90 mA cm−2, 0.62–0.69 V, and 0.62–0.67, respectively, corresponding to an overall conversion efficiency of 2.76–4.55 %. The conversion efficiency reached 38–62 % of that of a N719‐based device (7.31 %) fabricated and measured under similar conditions. Steric congestion between the naphthyl and aromatic moieties jeopardizes charge transfer from the donor to the acceptor. Insertion of an alkenyl entity between the naphthyl entity and the aromatic ring alleviates steric congestion and leads to longer wavelength electronic absorption spectra.
Simple Ligand Effects Switch a Hydrogenase Mimic between H2 and O2 Activation
Authors: Kim Kyoungmok , Matsumoto Takahiro , Robertson Andrew , Nakai Hidetaka , Ogo Seiji 
Published: March 2012

AbstractHerein, we report a [NiRu] biomimetic system for O2‐tolerant [NiFe]hydrogenases and demonstrate that electron donation to the [NiRu] center can switch the system between the activation of H2 and O2 through simple ligand effects by using hexamethylbenzene and pentamethylcyclopentadienyl ligands, respectively. Furthermore, we present the synthesis and direct observations of a [NiRu]–peroxo species, which was formed by the oxygenation of a Ni‐SIa model [NiRu] complex, that we propose as a biomimetic analogue of O2‐bound species (OBS) of O2‐tolerant [NiFe]hydrogenases. The [NiRu]–peroxo complex was fully characterized by X‐ray analysis, X‐ray photoelectron spectroscopy (XPS), mass spectrometry, and 1H NMR spectroscopy. The OBS analogue was capable of oxidizing p‐hydroquinone and sodium borohydride to turn back into the Ni‐SIa model complex.
Untersuchungen zur Effizienz von thermo‐aktiven Abdichtungselementen zur thermischen Nutzung des Untergrunds
Authors: Kürten Sylvia , Ziegler Martin , Olischläger Vera , Ehrenberg Henning 
Published: March 2012

AbstractDie thermische Aktivierung von Betonbauteilen zur energetischen Nutzung des Untergrunds findet in den letzten Jahren immer weitere Verbreitung. Ausführungsbeispiele finden sich für Energiepfähle, Energiebodenplatten oder Energieschlitzwände, bei denen die Wärmeaustauscherrohre an der statisch erforderlichen Bewehrung befestigt werden. Aufbauend auf diesem Prinzip wurden am Lehrstuhl für Geotechnik im Bauwesen der RWTH Aachen im Rahmen eines Forschungsvorhabens thermo‐aktive Abdichtungselemente für die thermische Aktivierung von erdberührenden Bauteilen unter dem Einfluss von (strömendem) Grundwasser entwickelt und deren Effizienz durch Großversuche und numerische Simulationen untersucht. Die thermo‐aktiven Abdichtungselemente sind durch eine flexible Leitungsverlegung und einen nahezu direkten Kontakt zum Erdreich gekennzeichnet. Im Rahmen der Versuche konnten in Abhängigkeit der System‐ und Randbedingungen Entzugsleistungen zwischen 25 W/m2 und 300 W/m2 erzielt werden. Als maßgebende Einflussparameter auf den Wärmeertrag konnten der Volumenstrom im Wärmeaustauschersystem, die Wärmeübertragungsfläche sowie die Erdreichtemperatur identifiziert werden.Investigations of the efficiency of thermo‐active seal‐panels for the thermal usage of the groundThe geothermal usage of earth coupled ground structures has found high resonance in the last years. Mostly, concrete structures are used for geothermal activation. Examples for energy piles, energy ground slabs as well as energy diaphragm walls are documented in common literature. Based on this principle, the Chair of Geotechnical Engineering at RWTH Aachen University developed thermo‐active seal panels in the scope of a research project. The efficiency of these panels was analysed with several pilot‐scale tests and numerical analyses. The application of the thermo‐active seal panels – which are characterised by a variable pipe‐laying and a relatively direct contact to the ground – lies in earth coupled structures which are influenced by (flowing) groundwater. The pilot‐scale tests resulted in heat transfer capacities between 25 W/m2 and 300 W/m2 depending on the system and boundary conditions. Furthermore, the flow rate in the heat exchanging system, the heat transfer area as well as the undisturbed ground temperature were identified as the decisive parameters for the heat output of thermo‐active seal panels.
Ein Beitrag zum Städtebau – der Neubau der Josef Eberle Brücke in Rottenburg am Neckar
Authors: Sobek Werner , Straub Wolfgang , Pürgstaller Andreas 
Published: March 2012

AbstractDie Josef Eberle Brücke in Rottenburg am Neckar verbindet die historische Altstadt mit dem südlichen Stadtteil und dem Bahnhof. Sie ersetzt ein Vorgängerbauwerk, das in schlechtem baulichem Zustand war. Die neue Brücke wurde an gleicher Stelle wie die alte Brücke erstellt und ist zur Nutzung durch Fußgänger und Radfahrer bestimmt. Beim Entwurf der Brücke war im Besonderen der Hochwasserschutz zu beachten. Die elegante Brückenkonstruktion schwingt sich als dünnes, dreifeldriges Band aus Spannbeton über den Neckar. Die neue Brücke fügt sich harmonisch in das bestehende historische Stadtbild Rottenburgs ein. Die hohe Aufenthaltsqualität der Brücke lädt den Benutzer zum Verweilen ein.
Aktualisierte Vergleichstafeln für militärische Lastenklassen bei Straßenbrücken
Authors: Forman Patrick , Fust Christina , Mark Peter 
Published: March 2012

AbstractNach dem Prinzip der bekannten “Homberg‐Tafeln” werden aktualisierte Vergleichstafeln für Schnittgrößen aus Lasten zivilen Verkehrs bzw. militärischer Fahrzeuge für Straßenbrücken abgeleitet. Grundlage sind auf Seite des zivilen Verkehrs das Lastmodell LM1 des DIN‐Fachberichts 101 (2009) bzw. das zu erwartende LMM mit erhöhten Einzelrad‐ und Flächenlasten sowie die militärischen Lastenklassen des STANAG 2021 (2006). Die Tafeln sind durch Kurvenscharen nach Militärlastklassen MLC 50, 100 und 150 unterteilt und aus Einheitsmomenten bzw. der analytischen oder numerischen Auswertung von Einflusslinien entwickelt. Eingeschlossen sind Längssysteme als Ein‐ bzw. Zweifeldträger als Stab oder zweistegige Plattenbalken mit verschiedenen Querverteilungen und relativen Stegabständen. Beispiele zeigen die Anwendung der Tafeln.Updated design‐charts for military load classifications of road bridgesSimilar to the established charts acc. to “Homberg” updated design‐charts to determine sectional forces induced by military vehicles on road bridges compared to civil traffic loads are derived. They base on the load model LM1 acc. to DIN‐Fachbericht 101 (2009), and the expected LMM with increased axle and distributed loads on the one side and military load classes defined in STANAG 2021 (2006), on the other side. Charts are separately prepared for MLC 50, 100 and 150. They are analytically or numerically obtained from unit moments and evaluations of influence lines including charts for different transverse load distributions and web distances for single and two‐span systems modeled as beams or double‐webbed T‐beams. Examples illustrate the practical application.
Ausführungsqualität von Stahlbeton‐ und Spannbetonbrücken an Bundesfernstraßen
Authors: Winter Georg , Schnellenbach‐Held Martina , Gusia Peter J. 
Published: March 2012

AbstractAn das in den 1990er Jahren durchgeführte Projekt “Ausführungsqualität von Stahlbeton‐ und Spannbetonbauwerken an Bundesfernstraßen” wurde ein Folgevorhaben angeknüpft, um zu erkennen, ob die Regelwerke der Baudurchführung in der Praxis umgesetzt werden und wie sie sich auf die Ausführungsqualität auswirken. Im Forschungsvorhaben wurden innerhalb von rd. zwei Jahren 53 Begehungen an insgesamt 19 Bauwerken durchgeführt und die Ausführung beobachtet.Die Anzahl und Bedeutsamkeit der Ausführungsfehler pro Baustellenbesuch ging gegenüber den Ergebnissen vom Vorprojekt zurück. Planungs‐ und Ausführungsunterlagen waren verbessert. Auch die im Jahre 2003 eingeführten Regelwerke der Baudurchführung wurden erfolgreich in der Baupraxis umgesetzt. Die in der Bauüberwachung Tätigen wiesen erheblich bessere Kenntnisse der Regelwerke auf. Die festgestellten Ausführungsfehler hätten bei Umsetzung der vorhandenen Regeln vermieden werden können.Execution Quality of Reinforced and Prestressed Concrete Bridges on Federal RoadsThe research project “Execution quality of reinforced and prestressed concrete structures on federal highways” was conducted in the 1990s. The current research project based on this preliminary project aims to inspect whether the regulations for execution are implemented successfully in practice and how they have influenced the quality of workmanship. As part of the research project 53 construction site inspections on 19 structures were carried out in less than two years to observe the main stages of execution.In comparison to the preliminary project a decrease in the number of defects per site visit as well as the “seriousness” of the defects is registered. Planning and design documents were improved. The construction supervision offices have shown considerably better knowledge of applicable regulations. The regulations for execution introduced in 2003 have also been implemented successfully in the bridge construction industry. The deficiencies could have been avoided by implementing the existing rules.
Hafenkonzepte für die Offshore‐Windindustrie
Authors: Jäppelt Ulrich , Carstensen Norbert , Schnabel Frank 
Published: March 2012

AbstractVor der Nordseeküste Schleswig‐Holsteins sind zurzeit sieben Windparks mit 735 Windenergieanlagen in der ersten Baustufe genehmigt. Weitere vier Parks mit zusätzlichen 219 Anlagen sind im Genehmigungsverfahren. Die hierdurch entstehenden logistischen Herausforderungen haben Auswirkungen insbesondere auf die Hafeninfrastrukturen an den Produktions‐ und Endmontagestandorten der Offshore‐Industrie, die für die Errichtung der Windparks in Betracht kommen. Kajen, Montage‐ und Lagerflächen müssen den hohen Anforderungen der Offshore‐Industrie nach Flächengrößen, Gewichten und Ausrüstung genügen. Im vorliegenden Beitrag wird die Zusammenarbeit der Hafenstandorte Büsum, Brunsbüttel, Dagebüll, Helgoland, Husum, Osterrönfeld, Wyk/Föhr sowie Hörnum und List im Hinblick auf die Offshore‐Logistik vorgestellt. Ferner wird am Beispiel des Standortes Helgoland gezeigt, wie vorhandene Hafenanlagen ausgebaut und umstrukturiert werden können, um den Anforderungen an einen Reaktionshafen gerecht zu werden.Port Concepts for the Offshore Wind Industry. Offshore Ports RequirementsOff Schleswig‐Holstein's North Sea coast, seven wind farms comprising 735 wind turbines have so far been approved for the first phase. For a further four farms comprising 219 more turbines, approval procedures are in progress. The logistic challenges arising from these plans especially affect the port infrastructure of the offshore industry's production and assembly sites that are to be considered for erection of the wind farms. Quays as well as assembly and storage areas need to meet the offshore industry's high demands concerning areas, weights and equipment. This article illustrates the cooperation with regard to logistics for the offshore industry between the port sites of Büsum, Brunsbüttel, Dagebüll, Heligoland, Husum, Osterrönfeld near Rendsburg, Wyk auf Föhr, and finally Hörnum and List, both on the Isle of Sylt. Furthermore, the example of Heligoland is used to illustrate how existing port facilities can be extended, upgraded and restructured to meet service port requirements.
Weltseehandel und seine größten Häfen – Ein Marktüberblick
Authors: Brinkmann Birgitt 
Published: March 2012

AbstractMehr als 80% des weltweiten Warenverkehrs erfolgen über den Seeweg. Wächst der weltweite Warentransport, wächst damit auch der Seehandel. Der Beitrag gibt einen Überblick über die Entwicklung der für den Seeverkehr bedeutendsten Güter Öl und Gas, Kohle und Eisenerz sowie Container und zeigt deren Hauptexport‐ und ‐importregionen sowie die wichtigsten Transportrouten auf. Darüber hinaus werden die führenden Häfen für den Umschlag dieser Güter sowie Erweiterungsplanungen und ‐vorhaben vorgestellt.World Seaborne Trade and its Major Ports – A Market SurveyThe World Seaborne Trade correlates with the World Merchandise Trade, which is expected to grow by 4% in 2011 as well as in 2012. The article shows the seaborne trade developments and the major maritime transport routes for the goods oil and liquefied natural gas (LNG), coal and iron ore and for containers. In addition, the largest ports for the handling of these goods, their throughputs as well as expansion plans are presented.
Leistungsfähige Häfen und optimale Infrastruktur – Fundament der deutschen Volkswirtschaft
Authors: Klingen Reinhard , Dirks Jan 
Published: March 2012

AbstractDie See‐ und Binnenhäfen sind aufgrund der starken Einbindung der deutschen Volkswirtschaft in die internationalen arbeitsteiligen Produktionsprozesse und Absatzmärkte von zentraler gesamtwirtschaftlicher Bedeutung. Von den Häfen profitiert ganz Deutschland mit einer Vielzahl von komplementären Industrie‐ und Dienstleistungsbereichen, die in allen Regionen und Wirtschaftssektoren angesiedelt sind. Laut der im Auftrag der Bundesregierung 2007 erstellten Prognose der deutschlandweiten Verkehrsverflechtung werden sich bis 2025 der Güterumschlag in den deutschen Seehäfen gegenüber 2004 mehr als verdoppeln, der Containerumschlag mehr als verdreifachen und die Transportleistung im Güterverkehr um 74% steigen. Die Politik der Bundesregierung ist darauf ausgerichtet, die Wettbewerbsfähigkeit der deutschen Häfen zu erhalten und sie als Drehscheiben für den nationalen und internationalen Warenverkehr und als wichtige Wirtschaftsstandorte und Arbeitgeber weiter zu stärken. Sie steht zu ihren Zusagen aus dem Koalitionsvertrag und dem Nationalen Hafenkonzept, eine zügige Optimierung der seewärtigen Zufahrten und der Hinterlandanbindungen sicherzustellen. Der Ausbau der Zufahrten zu den großen deutschen Seehäfen hat Vorrang vor volkswirtschaftlich weniger bedeutenden Projekten.Efficient ports and state‐of‐the‐art infrastructure – the basis of Germany's economyBecause of the strong links between the German economy and international production processes and markets, Germany's seaports and inland ports are key elements of the overall economy. A great number of secondary industrial and service areas in all regions and commercial sectors of Germany benefit from the ports. According to a study of future Germany‐wide transport, commissioned in 2007 by the Federal government, by 2025 the volume of goods handling in German seaports will more than double, container handling will increase three‐fold and total goods transport will increase by 74% compared to 2004. The policies of the Federal government are designed to maintain the competitiveness of German ports and to further underpin them as hubs for national and international goods transport, as well as important commercial facilities and employers. It stands by its commitment resulting from the Coalition Treaty and the National Port Concept to ensure that improvements to sea access routes and hinterland connections will be swiftly carried out. The upgrade of sea access routes to the large German sea ports has priority over projects that are less important for the German economy.