bluuebunny/crossref_metadata_2025_split huggingface dataset:
Manifestation and persistence of Pig‐a mutant red blood cells in C57BL/6 mice following single and split doses of N‐ethyl‐N‐nitrosourea
Authors: Bhalli Javed A. , Pearce Mason G. , Dobrovolsky Vasily N. , Heflich Robert H. 
Published: October 2011

AbstractTreating rats with single doses of N‐ethyl‐N‐nitrosourea (ENU) results in a time‐dependent accumulation of Pig‐a‐mutant phenotype peripheral red blood cells (RBCs), reaching a plateau at about 6‐weeks posttreatment, with the response persisting for at least 26 weeks. In the present study, groups of 5 C57BL/6 male mice were administered single i.p. doses of up to 140 mg/kg ENU, and blood samples were collected up to 26 weeks posttreatment. The samples were analyzed by flow cytometry for the frequency of CD24‐deficient (presumed Pig‐a mutant) reticulocytes (RETs) and total RBCs; micronucleated RET frequencies were evaluated at 1 day posttreatment. Mean Pig‐a mutant frequencies and micronucleated RET frequencies increased in a dose‐responsive manner, with maximum Pig‐a frequencies in RETs and RBCs observed at Week 2 and Week 4 posttreatment, respectively. Mutant frequencies in RETs and RBCs generally decreased slowly with time after reaching their maxima. In a second experiment, groups of five male C57BL/6 mice were given single i.p. injections of 8, 32, or 160 mg/kg ENU, or four weekly doses of 8 or 40 mg/kg ENU (split doses totaling 32 and 160 mg/kg, respectively). In each case the maximum RET and RBC mutant frequencies produced by the split doses were similar to but not as great as the mutant frequencies produced by the equivalent single doses. The data indicate that ENU‐induced Pig‐a mutant RBC frequencies accumulate in mice as they do in rats; however, mice and rats differ in the manifestation kinetics and the persistence of the responses. © Environ. Mol. Mutagen. 2011. Published 2011 Wiley‐Liss, Inc.
Report on stage III Pig‐a mutation assays using N‐ethyl‐N‐nitrosourea – comparison with other in vivo genotoxicity endpoints
Authors: Cammerer Zoryana , Bhalli Javed A. , Cao Xuefei , Coffing Stephanie L. , Dickinson Donna , Dobo Krista L. , Dobrovolsky Vasily N. , Engel Maria , Fiedler Ronald D. , Gunther William C. , Heflich Robert H. , Pearce Mason G. , Shaddock Joseph G. , Shutsky Thomas , Thiffeault Catherine J. , Schuler Maik 
Published: October 2011

AbstractN‐Ethyl‐N‐nitrosourea (ENU) was evaluated as part of the Stage III trial for the rat Pig‐a gene mutation assay. Groups of six‐ to eight‐week‐old male Sprague Dawley (SD) or Fischer 344 (F344) rats were given 28 daily doses of the phosphate buffered saline vehicle, or 2.5, 5, or 10 mg/kg ENU, and evaluated for a variety of genotoxicity endpoints in peripheral blood, spleen, liver, and colon. Blood was sampled predose (Day‐1) and at various time points up to Day 57. Pig‐a mutant frequencies were determined in total red blood cells (RBCs) and reticulocytes (RETs) as RBCCD59− and RETCD59− frequencies. Consistent with the results from a reference laboratory, RBCCD59− and RETCD59− frequencies increased in a dose‐ and time‐dependent manner, producing significant increases at all doses by Day 15, with similar frequencies seen in both rat strains. ENU also induced small but significant increases in % micronucleated RETs on Days 4 and 29. No significant increases in micronuclei were seen in the liver or colon of the ENU‐treated SD rats. Hprt and Pig‐a lymphocyte mutation assays conducted on splenocytes from Day 56 F344 rats detected two‐ to fourfold stronger responses for Hprt than Pig‐a mutations. Results from the in vivo Comet assay in SD rats at Day 29 showed generally weak increases in DNA damage in all tissues evaluated. The results with ENU indicate that the Pig‐a RET and RBC assays are reproducible, transferable, and complement other genotoxicity endpoints that could potentially be integrated into 28‐day repeat‐dose rat studies. © Environ. Mol. Mutagen. 2011. Published 2011 Wiley‐Liss, Inc.
Lower levels of oxidative DNA damage and apoptosis in lymphocytes from patients undergoing surgery with propofol anesthesia
Authors: Braz Mariana G. , Braz Leandro G. , Mazoti Marina A. , Pinotti Matheus F. , Pardini Maria Inês M. C. , Braz José R. C. , Salvadori Daisy M. F. 
Published: October 2011

AbstractPropofol, which is widely used as an intravenous anesthetic, has a phenolic structure similar to that of α‐tocopherol with antioxidant properties that could prevent genotoxicity and cytotoxicity in lymphocytes of anesthetized patients. The aims of this study were to evaluate oxidative DNA damage and apoptosis in lymphocytes and the expression of DNA repair genes in blood cells from patients undergoing elective surgery under anesthesia with propofol. Twenty healthy adults of both genders (18–50 years old) who were scheduled for otorhinological surgery were enrolled in this study. Blood samples were collected before anesthesia induction (T1‐baseline), 120 min after anesthesia induction (T2), and on the first postoperative day (T3). Oxidative DNA damage in peripheral lymphocytes was assessed using the comet assay. Lymphocytes were phenotyped as T helper or cytotoxic T cells, and apoptosis was evaluated using flow cytometry. The expression of DNA repair genes (hOGG1 and XRCC1) was assessed by quantitative polymerase chain reaction. A reduction in the level of oxidized purines in DNA (P < 0.01) was observed 120 min after anesthesia induction, and reduced apoptosis of T helper cells was observed 120 min after anesthesia induction and on the first postoperative day. Down‐regulation of hOGG1 and XRCC1 gene expression was observed on the first postoperative day. In conclusion, patients undergoing non‐invasive surgery under propofol anesthesia presented lower levels of oxidized purines and apoptosis of T helper lymphocytes. Furthermore, anesthesia with propofol did not directly influence the expression of the DNA repair genes hOGG1 and XRCC1 in blood cells. © Environ. Mol. Mutagen. 2012. Published 2011 Wiley Periodicals, Inc.
International Pig‐a gene mutation assay trial (Stage III): Results with N‐methyl‐N‐nitrosourea
Authors: Lynch Anthony M. , Giddings Amanda , Custer Laura , Gleason Carol , Henwood Andrew , Aylott Mike , Kenny Julia 
Published: October 2011

AbstractN‐methyl‐N‐nitrosourea (MNU) was evaluated in the in vivo Pig‐a mutation assay as part of an International Collaborative Trial to investigate laboratory reproducibility, 28‐day study integration, and comparative analysis with micronucleus (MN), comet, and clinical pathology endpoints. Male Sprague Dawley rats were treated for 28 days with doses of 0, 2.5, 5, and 10 mg MNU/kg/day in two independent laboratories, GlaxoSmithKline (GSK) and Bristol Myers Squibb (BMS). Additional studies investigated the low‐dose region (<2.5 mg/kg/day). Reticulocytes were evaluated for Pig‐a phenotypic mutation, CD59‐negative reticulocytes/erythrocytes (RETsCD59−/ RBCsCD59−) on Days 1, 4, 15, 29, 43, and 57, and for micronucleated reticulocytes (MN‐RETs) on Days 4 and 29. Comet analysis was conducted for liver and whole blood, and hematology and clinical chemistry was investigated. Dose‐dependent increases in the frequency of RETsCD59− and RBCsCD59− were observed by Day 15 or 29, respectively. Dose‐dependent increases were observed in %MN‐RET on Days 4 and 29, and in mean %tail intensity in liver and in blood. Hematology/clinical chemistry data demonstrated bone marrow toxicity. Data comparison between GSK and BMS indicated a high degree of concordance with the Pig‐a mutation assay results, consistent with previous observations with MNU and N‐ethyl‐N‐nitrosourea. These data confirm that complementary genotoxicity endpoints can be effectively incorporated into routine toxicology studies, a strategy that can provide information on gene mutation, chromosome damage, and DNA strand breaks in a single repeat dose rodent study. Collectively, this would reduce animal usage while providing valuable genetic toxicity information within the context of other toxicological endpoints. Environ. Mol. Mutagen., 2011. © 2011 Wiley‐Liss, Inc.
Characterization of Uncoated Stainless Steel as Proton Exchange Membrane Fuel Cell Bipolar Plates Material
Authors: Caqué N. , Paris M. , Chatenet M. , Rossinot E. , Bousquet R. , Claude E. 
Published: October 2011

AbstractThanks to their high conductivity, important gas tightness, good corrosion resistance, and low‐cost manufacturing pathways, stainless steels are considered as good candidates for proton exchange membrane fuel cell (PEMFC) bipolar plates materials. In this study, a proprietary alloy was identified as very promising: its initial electrical contact resistance (ECR) with the gas diffusion layer was low, while its corrosion resistance in simulated PEMFC environment was sufficient. Furthermore, the ECR did not increase dramatically during long‐term potentiostatic and potentiodynamic polarizations in simulated PEMFC cathode and anode environments. Finally, the stainless steel was successfully tested for 3,000 h in a commercial system using a 16‐cell stack, without detrimental cell voltage losses.
The Reißeck II pumped storage power station in Carinthia / Das Pumpspeicherkraftwerk (PSKW) Reißeck II in Kärnten
Authors: Freitag Manfred , Larcher Markus , Hager Andreas 
Published: October 2011

AbstractThe Reißeck II pumped storage power station being constructed for the Verbund Hydro Power AG is a current extension project in the south of Austria. With an extended capacity of 430 MW in generation and pumping modes, the efficiency of the entire pumped storage scheme will be increased by up to 40%. One advantage is that many parts of the existing system (reservoirs, headrace tunnel, infrastructure) can be used and do not have to be newly constructed. Both, mechanical and conventional tunnelling, methods are being used to overcome the height difference of just 600 m. The power station will be entirely housed underground and should enter full service in September 2014 at a cost of 385 mio Euro. The main works has been under construction since June 2010 by a joint venture of Hinteregger, Östu‐Stettin, Porr and Swietelsky.Das derzeit im Bau befindliche Pumspeicherkraftwerk Reißeck II der Verbund Hydro Power AG stellt ein aktuelles Erweiterungsprojekt im Süden Österreichs dar. Mit einer Ausbauleistung von 430 MW im Turbinen‐ und Pumpbetrieb wird eine Effizienzsteigerung des gesamten Kraftwerksstandorts von bis zu 40% erreicht. Vorteilhaft ist, dass zum Teil wesentliche Anlagenteile bestehender Anlagen (Speicher, Triebwasserweg, Infrastruktur) mitbenutzt und nicht mehr errichtet werden müssen. Zur Überwindung der knapp 600 m Höhendifferenz kommen sowohl maschinelle als auch konventionelle Vortriebsverfahren zum Einsatz. Die vollständig unterirdisch errichtete Kraftwerksanlage mit einem Gesamtinvestitionsvolumen von 385 Mio. Euro soll im September 2014 den Vollbetrieb aufnehmen. Die Hauptbauarbeiten werden seit Juni 2010 von der Arbeitsgemeinschaft Hinteregger, Östu‐Stettin, Porr, Swietelsky ausgeführt.
Kaiser Wilhelm Tunnel – mechanical tunnelling at the limits of experience / Kaiser‐Wilhelm‐Tunnel – Maschinenvortrieb im Grenzbereich der Erfahrungen
Authors: Tauch Bodo , Handke Dieter , Reith Marco 
Published: October 2011

AbstractThe subject of this article based on the Kaiser Wilhelm Tunnel is the derivation of a list of criteria for overcoming critical situations during tunnelling at the borderline of open mode to closed mode operation. The consistent application of this list of criteria demonstrates, that with knowledge of the sensitive interaction of machine and surrounding ground, the scope of application of current machine technologies can even be extended into geologically difficult areas. Formerly, this led to considerable problems, at times even economic failure of the project. The advantages the use of the catalogue of criteria has, si shown in the example of a shield machine with earth pressure components.Gegenstand des Beitrags zum Kaiser‐Wilhelm‐Tunnel ist die Herleitung eines Kriterienkatalogs zur Beherrschung kritischer Vortriebssituationen im Grenzbereich der Betriebsart offener Modus zum geschlossenen Modus. Die konsequente Anwendung des Kriterienkatalogs demonstriert am Beispiel einer Schildmaschine mit Erddruckkomponenten, dass mit Kenntnis des als sensibel einzustufenden Interaktionsverhaltens Maschine‐Baugrund der Anwendungsbereich heutiger Maschinentechnologien auch in geotechnisch schwierige Bereiche verschoben werden kann, die noch in der Vergangenheit zu erheblichen Problemen bis hin zu einem wirtschaftlichen Scheitern des Projekts führten.
City Tunnel in Waidhofen an der Ybbs – difficulties facing near‐surface tunnelling in creeping soil / Citytunnel Waidhofen an der Ybbs – Schwierigkeiten einer oberflächennahen Tunnelherstellung im Kriechhangbereich
Authors: Brunner Markus , Enengl Ernst 
Published: October 2011

AbstractThe construction of the City Tunnel in Waidhofen an der Ybbs required not only the solution of problems specific to an inner‐city infrastructure project but also flexible adaptation to the difficult geological conditions.This article intends to use the example to describe the construction of a structure in a creeping slope, to explain the considerable technical challenges and describe the chosen solution.Der Bau des City Tunnels Waidhofen an der Ybbs erforderte neben den spezifischen Problemlösungen eines innerstädtischen Infrastrukturgroßprojekts vor allem eine flexible Anpassung an die schwierigen geologischen Randbedingungen.Dieser Artikel versucht anhand eines Beispiels, die Errichtung des Bauwerks im Kriechhangbereich, die großen technischen Herausforderungen zu verdeutlichen und den gewählten Lösungsweg zu vermitteln.
Crossrail – design and construction / Crossrail – Entwurf, Bemessung und Ausführung
Authors: Dulake Chris 
Published: October 2011

AbstractCrossrail is a new railway currently being constructed in London and is the largest construction project in Europe. Linking existing surface railways to the east and west of the capital via 21 km of new twin bore tunnels it will run 118 km from end to end. This paper briefly summarises the benefits of the scheme and its sustainability strategy and goes on to describe the design of the sprayed concrete and bored tunnels, management and mitigation of ground movements. It finishes by outlining the contractual framework for the procurement of the main construction contracts.Crossrail ist das gegenwärtig größte europäische Bauvorhaben und beinhaltet eine neue Eisenbahnverbindung, die derzeit in London gebaut wird. Dabei werden die bestehenden Eisenbahnstrecken im Osten und Westen der Hauptstadt verbunden; die Gesamtstrecke ist 118 km lang, 21 km davon verlaufen in doppelröhrigen Tunneln. Der Beitrag erläutert den Nutzen und die Strategie des Projektes, insbesondere den Aspekt der Nachhaltigkeit, und befasst sich dann mit der Planung der Spritzbetonbauweise und der maschinellen Vortriebe sowie mit dem Management und der Minimierung von Erdbewegungen Der Beitrag schließt mit einer Beschreibung der vertraglichen Rahmenbedingungen für die Vergabe der Hauptbaulose.
Selection of tunnelling methods at the Gotthard Base Tunnel / Wahl der Vortriebsmethoden am Gotthard‐Basistunnel
Authors: Ehrbar Heinz , Sala Alex , Wick Raphael 
Published: October 2011

AbstractFor the construction of the longest rail tunnel in the world, the selection of the optimal method of tunnelling was of considerable importance. Not only the ground properties were decisive for the decision but also other constraints, like for example the environmental requirements or the access to intermediate starting points. In two of the five sections, the employer had essential grounds for the specification of tunnelling method, but in three of the five sections, there were no essential grounds in the view of the employer. The selection of tunnelling method was therefore decided by economic criteria as the result of competition between the international bidders in the tendering phase. In the end, TBMs were used in all three sections.Für den Bau des derzeit längsten Eisenbahntunnels der Welt war die Auswahl der optimalen Vortriebsmethode für den Projekterfolg von entscheidender Bedeutung. Nicht nur die Baugrundeigenschaften waren maßgebend für die Wahl, sondern viele andere Randbedingungen auch, z.B. die Anforderungen aus dem Umweltschutz oder aber die Zugänglichkeit zu Zwischenangriffen. Bei zwei von fünf Abschnitten hatte der Bauherr zwingende Gründe, die Vortriebsmethode vorzugeben. Bei drei von fünf Abschnitten fehlten aus Bauherrensicht zwingende Vorgaben. Die Wahl der Vortriebsmethode erfolgte deshalb aufgrund wirtschaftlicher Kriterien als Resultat des Wettbewerbes unter den internationalen Anbietern in der Angebotsphase. In allen drei Abschnitten kam schließlich der TBM‐Vortrieb zum Einsatz.
State of the art in evaluation and interpretation of displacement monitoring data in tunnels / Stand der Auswertung und Interpretation von Verschiebungsmessdaten bei Tunneln
Authors: Schubert Wulf , Moritz Bernd 
Published: October 2011

AbstractIn many countries observations of the system behaviour are executed during tunnel construction. However, the enormous potential of modern monitoring and evaluation methods is frequently not utilised. This paper presents different and nowadays common evaluation methods and their benefit is highlighted. Case studies are used for illustration.Beobachtungen des Systemverhaltens während des Tunnelbaus werden in vielen Ländern durchgeführt. Häufig wird jedoch das enorme Potenzial moderner Mess‐ und Auswertemethoden nicht ausgeschöpft. In diesem Beitrag werden verschiedene derzeit übliche Auswertemethoden dargestellt und deren Nutzen hervorgehoben. Fallbeispiele dienen zur Illustration.
Implementation of the observational method in mechanised tunnelling – contracts H3‐4 and H8 in the Lower Inn Valley / Umsetzung der Beobachtungsmethode beim TVM‐Vortrieb – Projektlose H3‐4 und H8 im Unterinntal
Authors: Maidl Ulrich , Köhler Manfred , Schretter Klaus 
Published: October 2011

AbstractBetween 2007 and 2009 the railway tunnels at Radfeld/Wiesing and Jenbach in the Lower Inn Valley were driven with two Herrenknecht TVM‐V4 machines (face with slurry support, D = 13 m). The tunnelling work was monitored according to the principles of the observational method as part of the independent data control. This article describes the experience from the project (contracts H3‐4 and H8) and make suggestions how the abstract requirements of the observational method can be implemented efficiently and economically. The results lead to the conclusion that mechanical tunnel drives in loose ground are predestined for the successful application of the observational method.Die Eisenbahntunnel bei Radfeld/Wiesing und Jenbach im Unterinntal wurden zwischen 2007 und 2009 mit zwei Herrenknecht TVM‐V4 (Ortsbrust mit Flüssigkeitsstützung, D = 13 m) aufgefahren. Die Vortriebsarbeiten wurden im Rahmen der unabhängigen Datenkontrolle nach den Prinzipien der Beobachtungsmethode überwacht. Der Beitrag beschreibt die Erfahrungen bei der Projektabwicklung (Lose H3‐4 und H8) und gibt Hinweise, wie die abstrakten Anforderungen an die Beobachtungsmethode effizient und wirtschaftlich umgesetzt werden können. Als Ergebnis wird festgestellt, dass der TVM‐Vortrieb im Lockergestein prädestiniert für eine erfolgreiche Umsetzung der Beobachtungsmethode ist.
Evaluation and interpretation of monitoring data in the test adit EKT Paierdorf / Auswertung und Interpretation der Messdaten aus dem Versuchsstollen EKT Paierdorf
Authors: Pilgerstorfer Thomas , Radonc̆ić Nedim , Moritz Bernd , Goricki Andreas 
Published: October 2011

AbstractWhen dealing with tunnels in difficult ground conditions the knowledge of rock mass parameters is of utmost importance to ensure an economical and safe tunnel design. In order to meet this goal a proper geomechanical characterization is imperative. The Koralmtunnel in Austria, for which exploratory tunnels were constructed between 2004 and 2010 in Carinthia, will pass a roughly 450 m long section of the so called Lavanttal fault zone. In order to gain detailed information about the properties and the mechanical behaviour of the surrounding rock mass in the fault zone an extensive in‐situ test program was conducted in a test adit. This paper describes the design and the execution of the in‐situ tests and measurements. The evaluation and results are discussed in detail. The in‐situ testing yields reliable and valuable information for geomechanical design of underground structures. It is pointed out that sometimes it can not be replaced by mere laboratory testing and numerical tools, no matter how advanced they may be.Die Kenntnis der Gebirgsparameter ist vor allem bei Tunnelbauten in schwachem Gebirge von enormer Wichtigkeit, um eine wirtschaftliche und vor allem sichere Tunnelplanung zu gewährleisten. Eine gründliche geomechanische Charakterisierung ist deshalb unumgänglich. Der Koralmtunnel in Österreich, für den von 2004 bis 2010 Erkundungstunnel auf Kärntner Seite errichtet wurden, wird auf ca. 450 m die Lavanttaler Hauptstörungszone durchörtern. Um detaillierte Information über die Eigenschaften und das mechanische Verhalten des umgebenden Gebirges in der Störungszone zu erhalten, wurde im Rahmen eines ergänzenden Erkundungsprogramms ein umfangreiches Versuchsprogramm in einem Instrumentierungsstollen durchgeführt. Der Beitrag beschreibt die Planung und Durchführung der Versuche und Messungen. Die Auswertemethoden und die wichtigsten Ergebnisse werden detailliert dargestellt. Es wird gezeigt, dass In‐situ‐Versuche zuverlässige und wertvolle Informationen für die geotechnische Planung von Untertagebauwerken liefern. In vielen Fällen können oder dürfen In‐situ‐Versuche nicht durch reine Laborversuche oder numerische Berechnungen ersetzt werden.
Selection of tunnelling methods for the New Semmering Base Tunnel / Auswahl der Vortriebsmethode beim Semmering‐Basistunnel neu
Authors: Ekici Zafer , Rüegg Christoph , Wilfinger Nicole , Wagner Oliver K. , Weigl Johannes 
Published: October 2011

AbstractThe approved alignment of the “New Semmering Base Tunnel” was divided into sections according to the three aspects risk, geotechnics and construction operations, in which either only sequential tunnelling or both methods, sequential or continuous mechanised, could be used.Auf Grundlage der drei Aspekte Risiko, Geotechnik und Baubetrieb wurde die Einreichtrasse des “Semmering‐Basistunnel neu” in Bereiche unterteilt, in denen entweder ausschließlich ein zyklischer Vortrieb oder beide Baumethoden, zyklisch und kontinuierlich, zum Einsatz kommen können.