bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rotaxanes Based on the 1,2‐Bis(pyridinio)ethane–24‐Crown‐8 Templating Motif
Authors: Mercer Darren J. , Vella Sarah J. , Guertin Lianne , Suhan Natalie D. , Tiburcio Jorge , Vukotic V. Nicholas , Wisner James A. , Loeb Stephen J. 
Published: February 2011

AbstractThe supramolecular interaction between 1,2‐bis(pyridinio)ethane axles and 24‐membered crown ether wheels provides a template for the formation of interpenetrated [2]pseudorotaxanes. The preformed [2]pseudorotaxanes can then be kinetically trapped to produce permanently interlocked [2]rotaxanes by stoppering with bulky groups that prevent the unthreading of the resulting dumbbell from the wheel. Six [2]rotaxanes were created using 24‐crown‐8 (24C8), dibenzo‐24‐crown‐8 (DB24C8) and dinaphtho‐24‐crown‐8 (DN24C8) as the wheel and two methods of stoppering; alkylation of a terminal pyridine with tert‐butylbenzyl groups and esterification of a terminal benzyl alcohol with p‐(tert‐butyl)benzoate groups. The [2]rotaxanes were characterized by 1H NMR spectroscopy, electro‐spray mass spectrometry and X‐ray crystallography.
Application and testing of plastic fibre reinforced dry‐mix shotcrete / Einsatz und Prüfung von kunststofffaserbewehrtem Trockenspritzbeton
Authors: Pittino Gerhard , Galler Robert , Mößlacher Andreas , Schwab Peter 
Published: February 2011

AbstractThe Conrad Observatory in the state of Lower Austria is a geophysical research and development facility of the Central Institute for Meteorology and Geodynamics (ZAMG). The isolation of the tunnel system fulfils the optimal requirements for high‐precision measurements. The client specified shotcrete class EV700 for the plastic fibre‐reinforced shotcrete, i.e. the test bodies have to show an energy absorption capacity of at least 700 J in the slab test. The quality verification for the suitability of a fibre‐reinforced shotcrete is performed according to the ÖVBB guideline “Sprayed Concrete” with a slab test as defined in the Austrian standard ÖNORM EN 14488‐5, which can determine the energy absorption capacity and assign the shotcrete to an energy absorption class. The test rig used at the Chair of Subsurface Engineering is described, together with test results from different plastic fibre shotcretes from various testing institutes.Das Conrad Observatorium in Niederösterreich ist eine geophysikalische Forschungs‐ und Entwicklungseinrichtung der Zentralanstalt für Meteorologie und Geodynamik (ZAMG). Die Abgeschiedenheit des Stollensystems erfüllt in optimaler Weise die für die hochpräzisen Messungen notwendigen Anforderungen. Auftraggeberseitig wurde für den kunststofffaserbewehrten Spritzbeton die Spritzbetonklasse EV700 vorgegeben, d.h., im Plattenversuch muss ein Energieabsorptionsvermögen von jeweils mindestens 700 J erzielt werden. Der Qualitätsnachweis für die Eignung eines faserbewehrten Spritzbetons erfolgt nach ÖVBB‐Richtlinie Spritzbeton durch den in ÖNORM EN 14488‐5 definierten Plattenversuch, mit dem die Energieabsorptionskapazität ermittelt und der Spritzbeton einer Energieabsorptionsklasse zugeordnet werden kann. Der am Lehrstuhl für Subsurface Engineering eingesetzte Versuchsaufbau wird vorgestellt, zusammen mit Prüfergebnissen von unterschiedlichen Kunststofffaserspritzbetonen von verschiedenen Prüfinstitutionen.
Abrasiveness and tool wear in shield tunnelling in soil / Abrasivität und Werkzeugverschleiß beim Schildvortrieb im Lockergestein
Authors: Köhler Manfred , Maidl Ulrich , Martak Lothar 
Published: February 2011

AbstractThere are currently no recognised prediction models available for the estimation of tool wear in shield tunnelling in soil. This paper describes the current state of knowledge through the interpretation of the available index tests, available correlations and analogies to hard rock. Then follows a discussion of the essential soil properties and the process‐related interactions, which can also determine tool wear in soil.Für den Schildvortrieb im Lockergestein liegen derzeit keine anerkannten Prognosemodelle zur Abschätzung des Werkzeugverschleißes vor. Der Artikel beschreibt die aktuellen Erkenntnisse bei Interpretation der existierenden Index‐Versuche, bestehende Korrelationen und Analogien zum Festgestein. Im Weiteren wird auf die maßgebenden Baugrundeigenschaften und die den Werkzeugverschleiß bestimmenden verfahrenstechnischen Interaktionen im Lockergestein eingegangen.
The development of earth pressure shields: from the beginning to the present / Entwicklung der Erddruckschilde: Von den Anfängen bis zur Gegenwart
Authors: Herrenknecht Martin , Thewes Markus , Budach Christoph 
Published: February 2011

AbstractThe development of earth pressure shields started in 1974. The processing of the ground into an earth pressure support medium originally required that it mostly consisted of mixed and finegrained soil with at least 30 % silt and clay. Since then, the process technology has been the subject of constant further development and the scope of application has been considerably widened. Currently more than 90 % of the shield machines worldwide are being used with active face support as earth pressure shields in the whole spectrum of soils, in hard rock and also in transitional areas with mixed face conditions. The current state of technology for earth pressure shields is based on a range of important development steps, which are summarised in this paper from the beginnings until today. Projects are described where important earth pressure shield innovations were used for the first time. The development of earth pressure shields is supplemented with an overview of the process technology, possible operating modes, areas of application and also current research work.Die Entwicklung der Erddruckschilde begann im Jahr 1974. Die Aufbereitung des Baugrunds zu einer Erddruck‐Stützmasse setzte ursprünglich voraus, dass der Baugrund vor allem aus gemischt‐ und feinkörnigen Böden mit mindestens 30 % Schluff und Ton besteht. Seither wurden die Verfahrenstechnik ständig weiterentwickelt und die Einsatzbereiche stark ausgeweitet. Derzeit werden mehr als 90 % der weltweit eingesetzten Schildmaschinen mit aktiver Ortsbruststützung als Erddruckschild im gesamten Spektrum der Lockergesteine, im Festgestein und auch in Übergangsbereichen mit gemischter Ortsbrust eingesetzt. Der aktuelle Stand der Technik der Erddruckschilde basiert auf einer Reihe wichtiger Entwicklungsschritte, die in diesem Beitrag von den Anfängen bis zur Gegenwart zusammengefasst werden. Dazu werden Projekte hervorgehoben, bei denen wichtige Innovationen für Erddruckschilde erstmals zum Einsatz kamen. Eine Übersicht zur Verfahrenstechnik, den möglichen Betriebsmodi, den Einsatzbereichen sowie aktuellen Forschungsarbeiten ergänzt die Entwicklung der Erddruckschilde.
Tunnel inner lining of bright self‐compacting concrete / Tunnelinnenschale aus hellem selbstverdichtendem Beton
Authors: Krispel Stefan , Strommer Werner 
Published: February 2011

AbstractEver more stringent requirements have been specified in recent years for the surfaces of tunnel inner linings with regard to surface porosity (with influence on the ease of cleaning) and lightness. These requirements are normally fulfilled by filling and applying tunnel paint. Recently there have been many cases of damage to paint or coating systems, sometimes only a few weeks after opening for traffic. This often includes the separation of the coating. This flaking leads to increased dirt adhesion and thus to a reduction of lightness and irritation to the field of view of the drivers. The refurbishment work, which is often necessary, leads to traffic obstruction like hold‐ups and diversions. For this reason, the durability of the surface is of great significance, and innovative solutions are also being investigated in the field of concrete technology. The following article presents an alternative and durable method of fulfilling all the requirements placed on the surface of the tunnel inner lining.In den vergangenen Jahren wurden immer höhere Anforderungen an die Oberflächen von Tunnelinnenschalen betreffend Oberflächenporosität (Einfluss auf Reinigungsfähigkeit) und Helligkeit gestellt. Zur Erfüllung dieser Anforderungen werden meist Tunnelanstriche nach vorheriger Spachtelung verwendet. In letzter Zeit traten jedoch vermehrt Schäden an Anstrichsystemen auf, teilweise schon wenige Wochen nach Verkehrsfreigabe. Hierbei kommt es oftmals zu einem Ablösen der Anstrichschicht. Diese Ablöseerscheinungen führen aufgrund einer verstärkten Schmutzablagerung zu einer Reduktion der Helligkeit und zu Irritationen des Blickfelds der Verkehrsteilnehmer. Die oftmals erforderlichen Instandsetzungsarbeiten am Beschichtungssystem führen zu Verkehrsbehinderungen wie Staus und Umleitungen. Aus diesen Gründen ist die Beständigkeit der Oberfläche von großer Bedeutung, und innovative Lösungswege werden auch im Bereich der Betontechnologie erprobt. Im nachstehenden Beitrag wird eine alternative dauerhafte Methode vorgestellt, die alle Anforderungen an die Oberfläche der Tunnelinnenschale erfüllt.
Fibroblast growth factor 2 regulates astrocyte differentiation in a region‐specific manner in the hindbrain
Authors: Irmady Krithi , Zechel Sabrina , Unsicker Klaus 
Published: February 2011

AbstractFibroblast growth factor (FGF)‐2 is known to have important pleiotropic effects in neuronal and glial cells during various physiological and pathological events. To investigate the role of endogenous FGF‐2 in the differentiation of astrocytes, we studied the expression of glial fibrillary acidic protein (GFAP) in the hindbrain of the FGF‐2 null mouse. GFAP was drastically decreased in a region‐specific manner in the hindbrain of the adult and developing FGF‐2 null mouse without an associated change in the expression of alternate markers for astrocytes. The deficit was evident in the astrocytes of pontine and medullary gray matter but not in the white matter. The astrocytes of the gray and white matter were seen to express FGF‐2 and FGF receptors in a distinct pattern. The methylation of histone H3 at lysine 4 residue (H3K4me2) associated with the STAT (signal transducer and activator of transcription)‐binding site of the GFAP promoter was significantly decreased in the gray matter of the FGF‐2 null mouse, suggesting a role for FGF‐2 in the epigenetic regulation of astrocyte differentiation in vivo. These observations underscore the importance of FGF‐2 in astroglial differentiation in the hindbrain and the heterogeneity of astrocytes in their requirement for FGF‐2 as a differentiation inducing signal.© 2011 Wiley‐Liss, Inc.
Mouse schwann cells need both NRG1 and cyclic AMP to myelinate
Authors: Arthur‐Farraj Peter , Wanek Katharina , Hantke Janina , Davis Catherine M. , Jayakar Anuj , Parkinson David B. , Mirsky Rhona , Jessen Kristján R. 
Published: February 2011

AbstractGenetically modified mice have been a major source of information about the molecular control of Schwann‐cell myelin formation, and the role of β‐neuregulin 1 (NRG1) in this process in vivo. In vitro, on the other hand, Schwann cells from rats have been used in most analyses of the signaling pathways involved in myelination. To correlate more effectively in vivo and in vitro data, we used purified cultures of mouse Schwann cells in addition to rat Schwann cells to examine two important myelin‐related signals, cyclic adenosine monophosphate (cAMP), and NRG1 and to determine whether they interact to control myelin differentiation. We find that in mouse Schwann cells, neither cAMP nor NRG1, when used separately, induced markers of myelin differentiation. When combined, however, they induced strong protein expression of the myelin markers, Krox‐20 and P0. Importantly, the level of cAMP signaling was crucial in switching NRG1 from a proliferative signal to a myelin differentiation signal. Also in cultured rat Schwann cells, NRG1 promoted cAMP‐induced Krox‐20 and P0 expression. Finally, we found that cAMP/NRG1‐induced Schwann‐cell differentiation required the activity of the cAMP response element binding family of transcription factors in both mouse and rat cells. These observations reconcile observations in vivo and on neuron‐Schwann‐cell cultures with studies on purified Schwann cells. They demonstrate unambiguously the promyelin effects of NRG1 in purified cells, and they show that the cAMP pathway determines whether NRG1 drives proliferation or induces myelin differentiation. © 2011 Wiley‐Liss, Inc.
Split central venous sampling of parathyroid hormone: An adjunct to surgical exploration
Authors: Maceri Dennis R. , Kokot Niels , Green Kathrine , Montgomery Vida , Sharifi Jahangir 
Published: February 2011

AbstractBackgroundMinimally invasive parathyroid surgery mandates preoperative localization of the adenoma for a targeted operative approach. This technique uses split internal jugular vein parathyroid hormone (PTH) samples to determine a gradient that then directs the surgical exploration.MethodsBlood samples were drawn low in the neck from the jugular veins after the neck was opened. The p values for the difference in PTH between the right and left internal jugular veins were calculated with independent sample t tests.ResultsFor left‐sided adenomas, the left internal jugular vein mean was significantly higher than the right p = .001). For right‐sided adenomas, the right internal jugular vein mean was significantly higher than the left (p = .004). In hyperplasia, there was no significant difference (p = .43).ConclusionsThis study demonstrates the usefulness of split PTH internal jugular vein samples in patients in whom preoperative localization failed. Eighty percent of these patients with a gradient were treated with site‐directed unilateral exploration. © 2011 Wiley Periodicals, Inc. Head Neck, 2011
Altered metabolism in head and neck squamous cell carcinoma: an opportunity for identification of novel biomarkers and drug targets
Authors: Sandulache Vlad C. , Myers Jeffrey N. 
Published: February 2011

AbstractTumor cells were first shown to exhibit a distinct metabolic phenotype over 80 years ago. Since then, it has become clear that multiple oncogenic events contribute to the development of a metabolic phenotype that supports rapid proliferation. Because this phenotype represents an essential component of tumorigenesis and disease progression, it also represents a potential source of biomarkers associated with aggressive disease. In addition, the addiction of tumor cells to specific nutrients and the up‐regulation of key metabolic enzymes provide unique opportunities for pharmacologic manipulation. Despite the use of multimodality treatment, survival rates for patients with advanced head and neck squamous cell carcinoma (HNSCC) remain low, partially attributed to the development of drug resistance. In this review, we evaluate the role of altered HNSCC metabolism as both a source of novel biomarkers and a means to bypass resistance mechanisms to conventional forms of therapy. © 2011 Wiley Periodicals, Inc. Head Neck, 2012
Prognosis: A variable parameter. Dynamic prognostic modeling in head and neck squamous cell carcinoma
Authors: van der Schroeff Marc P. , Steyerberg Ewout W. , Wieringa Marjan H. , Langeveld Ton P. M. , Molenaar Jan , Baatenburg de Jong Robert J. 
Published: February 2011

AbstractBackgroundIn general, the estimated prognosis of patients with cancer is based on patient characteristics known at the time of diagnosis and presented as if a lifetime verdict. However, the prognosis of patients with cancer who survive the first critical years changes, along with the prognosis for those with local or regional recurrences or distant metastases.MethodsThis study concerns 2927 patients with a primary head and neck squamous cell carcinoma (HNSCC). We developed prognostic models after initial treatment and at different time points during follow‐up.ResultsThe developed models show the effects of survival time, recurrences, and distant metastasis during follow‐up. The C‐statistics ranged from 0.76 to 0.69.ConclusionPrognosis is dynamic: the passage of time and the occurrence of life events change the predicted probabilities of survival. The models enhance our insight in the effect of recurrences and metastasis during follow‐up and could be used for better patient counseling. © 2011 Wiley Periodicals, Inc. Head Neck, 2012
Novel head and neck cancer survival analysis approach: Random survival forests versus cox proportional hazards regression
Authors: Datema Frank R. , Moya Ana , Krause Peter , Bäck Thomas , Willmes Lars , Langeveld Ton , Baatenburg de Jong Robert J. , Blom Henk M. 
Published: February 2011

AbstractBackgroundElectronic patient files generate an enormous amount of medical data. These data can be used for research, such as prognostic modeling. Automatization of statistical prognostication processes allows automatic updating of models when new data is gathered. The increase of power behind an automated prognostic model makes its predictive capability more reliable. Cox proportional hazard regression is most frequently used in prognostication. Automatization of a Cox model is possible, but we expect the updating process to be time‐consuming. A possible solution lies in an alternative modeling technique called random survival forests (RSFs). RSF is easily automated and is known to handle the proportionality assumption coherently and automatically. Performance of RSF has not yet been tested on a large head and neck oncological dataset. This study investigates performance of head and neck overall survival of RSF models. Performances are compared to a Cox model as the “gold standard.” RSF might be an interesting alternative modeling approach for automatization when performances are similar.MethodsRSF models were created in R (Cox also in SPSS). Four RSF splitting rules were used: log‐rank, conservation of events, log‐rank score, and log‐rank approximation. Models were based on historical data of 1371 patients with primary head‐and‐neck cancer, diagnosed between 1981 and 1998. Models contain 8 covariates: tumor site, T classification, N classification, M classification, age, sex, prior malignancies, and comorbidity. Model performances were determined by Harrell's concordance error rate, in which 33% of the original data served as a validation sample.ResultsRSF and Cox models delivered similar error rates. The Cox model performed slightly better (error rate, 0.2826). The log‐rank splitting approach gave the best RSF performance (error rate, 0.2873). In accord with Cox and RSF models, high T classification, high N classification, and severe comorbidity are very important covariates in the model, whereas sex, mild comorbidity, and a supraglottic larynx tumor are less important. A discrepancy arose regarding the importance of M1 classification (see Discussion).ConclusionBoth approaches delivered similar error rates. The Cox model gives a clinically understandable output on covariate impact, whereas RSF becomes more of a “black box.” RSF complements the Cox model by giving more insight and confidence toward relative importance of model covariates. RSF can be recommended as the approach of choice in automating survival analyses. © 2011 Wiley Periodicals, Inc. Head Neck, 2012
Modulation of hepatitis B virus replication and hepatocyte differentiation by MicroRNA-1
Authors: Zhang Xiaoyong , Zhang Ejuan , Ma Zhiyong , Pei Rongjuan , Jiang Min , Schlaak Joerg F. , Roggendorf Michael , Lu Mengji 
Published: February 2011

Abstract

MicroRNAs (miRNAs) are highly conserved small noncoding RNAs participating in regulation of various cellular processes. Viruses have been shown to utilize cellular miRNAs to increase their replication in host cells. Until now, the role of miRNAs in hepatitis B virus (HBV) replication has remained largely unknown. In this study, a number of miRNA mimics were transfected into hepatoma cell lines with HBV replication. It was noted that microRNA-1 (miR-1) transfection resulted in a marked increase of HBV replication, accompanied with up-regulated HBV transcription, antigen expression, and progeny secretion. However, bioinformatics and luciferase reporter analysis suggested that miR-1 may not target the HBV genome directly but regulate the expression of host genes to enhance HBV replication. Further studies showed that miR-1 was able to enhance the HBV core promoter transcription activity by augmenting farnesoid X receptor α expression. In addition, miR-1 arrested the cell cycle at the G1 phase and inhibited cell proliferation by targeting histone deacetylase 4 and E2F transcription factor 5. Analysis of the cellular gene expression profile indicated that miR-1 transfected hepatoma cells developed a differentiated phenotype of hepatocytes.

Conclusion:

MiR-1 regulates the expression of several host genes to enhance HBV replication and reverse cancer cell phenotype, which is apparently beneficial for HBV replication. Our findings provide a novel perspective on the role of miRNAs in host-virus interactions in HBV infection. (Hepatology 2011;)
From EosFP to mIrisFP: structure‐based development of advanced photoactivatable marker proteins of the GFP‐family
Authors: Wiedenmann Jörg , Gayda Susan , Adam Virgile , Oswald Franz , Nienhaus Karin , Bourgeois Dominique , Nienhaus G. Ulrich 
Published: February 2011

AbstractFluorescent proteins from the GFP family have become indispensable imaging tools in life sciences research. In recent years, a wide variety of these proteins were discovered in non‐bioluminescent anthozoa. Some of them feature exciting new properties, including the possibility to change their fluorescence quantum yield and/or color by irradiating with light of specific wavelengths. These photoactivatable fluorescent proteins enable many interesting applications including pulse‐chase experiments and super‐resolution imaging. In this review, we discuss the development of advanced variants, using a structure‐function based, molecular biophysics approach, of the photoactivatable fluorescent protein EosFP, which can be photoconverted from green to red fluorescence by ∼400 nm light. A variety of applications are presented that demonstrate the versatility of these marker proteins in live‐cell imaging. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Successful therapeutic plasma exchange in a 3.2‐kg body weight neonate with atypical hemolytic uremic syndrome
Authors: Jung Sunkyung , Kang Eun‐Suk , Ki Chang‐Seok , Kim Dae‐Won , Paik Kyung‐Hoon , Chang Yun Sil 
Published: February 2011

AbstractAtypical hemolytic uremic syndrome (aHUS) is a rare form of complement dysregulation disease, and recently various reports have shown that it is associated with one or more mutations in the complement regulatory genes including complement factor H (CFH). Plasma exchange is a therapeutic option for adult patients, but not for a very young infant because of a potential side effect of therapeutic plasma exchange (TPE) itself. Herein, we describe a case of successful treatment of early onset aHUS associated with a novel CFH mutation with total 21 sessions of TPE over a period of 46 days in 3.2 kg 23‐day‐old neonate. J. Clin. Apheresis, 2011. © 2011 Wiley‐Liss, Inc.