bluuebunny/crossref_metadata_2025_split huggingface dataset:
African American and poor patients have a dramatically worse prognosis for head and neck cancer
Authors: Molina Manuel A. , Cheung Michael C. , Perez Eduardo A. , Byrne Margaret M. , Franceschi Dido , Moffat Frederick L. , Livingstone Alan S. , Goodwin W. Jarrard , Gutierrez Juan C. , Koniaris Leonidas G. 
Published: October 2008

AbstractBACKGROUND.Differences in cancer survival based on race, ethnicity, and socioeconomic status (SES) are a major issue. To identify points of intervention and improve survival, the authors sought to determine the impact of race, ethnicity, and socioeconomic status for patients with cancers of the head and neck (HN).METHODS.HN cancer patients diagnosed between 1998 and 2002 were examined using a linked Florida Cancer Data System and Florida Agency for Health Care Administration data set.RESULTS.A total of 20,915 patients with HN cancers were identified, predominantly in the oral cavity and larynx. Overall, 72% of patients were male, 89.7% were white, 8.4% were African American (AA), and 10.6% were Hispanic. The median survival time (MST) was 37 months. MST varied significantly by race (white, 40 months vs AA, 21 months; P < .001), sex (men, 36 months vs women, 41 months; P = .001), and area poverty level (lowest, 27 months vs highest, 34 months; P < .0001). Only 32% of AA patients underwent surgery in comparison with 45% of white patients (P < .001). On multivariate analysis, independent predictors of poorer outcomes were race, poverty, age, sex, tumor site, stage, grade, treatment modality, and a history of smoking and alcohol consumption.CONCLUSIONS.Carcinomas of the HN have an overall high mortality with a disproportionate impact on AA patients and the poor. Dramatic disparities by race and SES are not explained completely by demographics, comorbid conditions, or undertreatment. Earlier diagnosis and greater access to surgery and adjuvant therapies in these patients would likely yield significant improvement in outcomes. Cancer 2008. © 2008 American Cancer Society.
Gradual morphogenesis of retinal neurons in the peripheral retinal margin of adult monkeys and humans
Authors: Martínez‐Navarrete Gema C. , Angulo Antonia , Martín‐Nieto José , Cuenca Nicolás 
Published: October 2008

AbstractThe adult mammalian retina has for long been considered to lack a neurogenerative capacity. However, retinal stem/progenitor cells, which can originate retinal neurons in vitro, have been recently reported in the ciliary body of adult mammals. Here we explored the possibility of retinal neurogenesis occurring in vivo in adult monkeys and humans. We found the presence of cells expressing molecular markers of neural and retinal progenitors in the nonlaminated retinal margin and ciliary body pars plana of mature primates. By means of immunohistochemistry and electron microscopy we also observed photoreceptors and other retinal cell types in different stages of morphological differentiation along the peripheral retinal margin. These findings allow us to extend to primates the idea of neurogenesis aimed at retinal cell turnover throughout life. J. Comp. Neurol. 511:557–580, 2008. © 2008 Wiley‐Liss, Inc.
Dynamic allocation in a self‐scaling cluster database
Authors: Rabl T. , Pfeffer M. , Kosch H. 
Published: October 2008

AbstractDatabase systems have been vital for all forms of data processing for a long time. In recent years, the amount of processed data has been growing dramatically, even in small projects. Nevertheless, database management systems tend to be static in terms of size and performance, which makes scaling a difficult and an expensive task. This is especially an acute problem in dynamic environments such as grid systems.On the basis of the C‐JDBC project, we developed a cluster database that supports automatic scaling in the number of nodes used. To ensure good load balancing, we distribute the tablespace according to a statistical analysis of the query history. In this paper, we will focus on the allocation algorithm. Copyright © 2008 John Wiley & Sons, Ltd.
PECVD Siloxane and Fluorine‐Based Copolymer Thin Films
Authors: Jiang Hao , Eyink Kurt , Grant John T. , Enlow Jesse , Tullis Scott , Bunning Timothy J. 
Published: October 2008

AbstractPlasma copolymerization is utilized to fabricate thin photonic films based on hexamethyldisiloxane (HMDSO, C6H18Si2O) and octafluorocyclobutane (OFCB, C4F8). The structure of the plasma copolymerized films is examined by X‐ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR), and the optical properties including refractive index, n, and extinction coefficient, k, are determined by spectroscopic ellipsometry. The refractive indices, which range from 1.38 to 1.54, can be manipulated by adjusting the volume ratio of the two monomers, HMDSO and OFCB, during the polymerization. A nonlinear relationship between the refractive index and extinction coefficient with comonomer feed ratio is observed. A strong initial increase in both n and k as the amount of HMDSO is increased is attributed to significant defluorination of the resultant polymer films coupled with the formation of a C‐C rich crosslinked network. Once the network incorporates substantial amounts of Si‐C and Si‐O bonds, the refractive index starts to decrease slowly due to a lowering of the density. XPS and FTIR results confirm the changes in internal structure consistent with this mechanism.
Tribenzyltin(IV)chloride Thiosemicarbazones: Novel Single Source Precursors for Growth of SnS Thin Films
Authors: Bade Balasaheb P. , Garje Shivram S. , Niwate Yogesh S. , Afzaal Mohammad , O'Brien Paul 
Published: October 2008

AbstractTin sulfide (SnS) thin films are deposited using simple tin thiosemicarbazone complexes of the type Bz3SnCl(L) (L = thiosemicarbazones of salicylaldehye and 4‐chlorobenzaldehyde). Thin films are deposited using aerosol‐assisted (AA) CVD in the range 375–475 °C. X‐ray diffraction (XRD) shows the formation of SnS regardless of growth temperature and precursor type. Scanning electron microscope (SEM) images show that the films have wafer‐like morphology, and the growth temperatures do not have a profound effect on morphology.
An Analysis of the Deposition Mechanisms involved during Self‐Limiting Growth of Aluminum Oxide by Pulsed PECVD
Authors: Seman Michael T. , Richards David N. , Rowlette Pieter , Wolden Colin A. 
Published: October 2008

AbstractSelf‐limiting growth of Al2O3 is accomplished using both pulsed plasma‐enhanced (PE) CVD and plasma‐enhanced atomic layer deposition (PEALD). In pulsed PECVD the two reactants (Al(CH3)3/TMA and O2) are supplied continuously, while in PEALD the TMA is delivered in pulses separated by purge steps. For both processes the rate per cycle saturates with ∼200 L of TMA exposure. At 165 °C a rate of 1.37 Å per cycle is obtained using PEALD. For pulsed PECVD the rate scales linearly with the TMA partial pressure, and its extrapolation is in good agreement with PEALD. The results suggest that deposition in pulsed PECVD involves an ALD component which is supplemented by PECVD growth, and that the contribution of the latter may be tuned using the TMA partial pressure. Experiments using patterned wafers support this hypothesis. Conformal coatings are observed within 10:1 aspect ratio trenches using pulsed PECVD; however the deposition rate on the surface of these substrates is greater than within the trench. The ratio between the two corresponds well to the ratio of rates obtained from pulsed PECVD and PEALD on planar substrates. With cycle times <1 s, net rates up to 20 nm min−1 are obtained by pulsed PECVD while retaining high quality and digital control.
An Investigation of Titanium‐Vanadium Nitride Phase Space, Conducted Using Combinatorial Atmospheric Pressure CVD
Authors: Hyett Geoffrey , Green Mark A. , Parkin Ivan P. 
Published: October 2008

AbstractThe technique of combinatorial atmospheric pressure (AP)CVD, a recent addition to the growing number of combinatorial materials methods, is used to form twelve members of the TixV1‐xN alloy series with 0.29 < x < 0.94. This series of compounds has a rock‐salt structure with TiN and VN as the end members. The twelve phases, which have potential use as heat mirror coatings, are all synthesized in a single experiment. The structure and properties of the materials are investigated using powder X‐ray diffraction (XRD) and electron probe microanalysis (EPMA). The optical properties are considered using visible‐IR spectroscopy (IRS), which allows the suitability of the films as solar control coatings to be investigated and optimized as a function of composition.
Thin Polymer Films with High Step Coverage in Microtrenches by Initiated CVD
Authors: Baxamusa Salmaan H. , Gleason Karen K. 
Published: October 2008

AbstractInitiated (i)CVD is used to deposit thin films of poly(cyclohexylmethacrylate) (pCHMA) in microtrenches of depth 7 µm and widths 1‐5 µm. By changing the fractional saturation of the monomer vapor, step coverage of 0.85 is achieved for the highest aspect ratio trench studied while maintaining a deposition rate of 15 nm min−1. An analytical model for determining the sticking probability of the initiating radical (CH3)3CO· is developed, and is experimentally shown to be a function of the fractional saturation of the monomer vapor. For the conditions studied, the sticking probability is in the range 1.1 × 10−2–5.0 × 10−2. These results suggest that iCVD proceeds via the reaction of a vapor‐phase initiating radical with a surface‐adsorbed monomer.
Parameters influencing derivation of embryonic stem cells from murine embryos
Authors: Batlle‐Morera Laura , Smith Austin , Nichols Jennifer 
Published: October 2008

AbstractThe derivation of ES cells is poorly understood and varies in efficiency between different strains of mice. We have investigated potential differences between embryos of permissive and recalcitrant strains during diapause and ES cell derivation. We found that in diapause embryos of the recalcitrant C57BL/6 and CBA strains, the epiblast failed to expand during the primary explant phase of ES cell derivation, whereas in the permissive 129 strain, it expanded dramatically. Epiblasts from the recalcitrant strains could be expanded by reducing Erk activation. Isolation of 129 epiblasts facilitated very efficient derivation of ES cell lines in serum‐ and feeder‐free conditions, but reduction of Erk activity was required for derivation of ES cells from isolated C57BL/6 or CBA epiblasts. The results suggest that the discrepancy in ES cell derivation efficiency is not attributable merely to variable prodifferentiative effects of the extra‐embryonic lineages but also to an intrinsic variability within the epiblast to maintain pluripotency. genesis 46:758–767, 2008. © 2008 Wiley‐Liss, Inc.
A new Bayesian formulation for Holt's exponential smoothing
Authors: Andrawis Robert R. , Atiya Amir F. 
Published: October 2008

AbstractIn this paper we propose a Bayesian forecasting approach for Holt's additive exponential smoothing method. Starting from the state space formulation, a formula for the forecast is derived and reduced to a two‐dimensional integration that can be computed numerically in a straightforward way. In contrast to much of the work for exponential smoothing, this method produces the forecast density and, in addition, it considers the initial level and initial trend as part of the parameters to be evaluated. Another contribution of this paper is that we have derived a way to reduce the computation of the maximum likelihood parameter estimation procedure to that of evaluating a two‐dimensional grid, rather than applying a five‐variable optimization procedure. Simulation experiments confirm that both proposed methods give favorable performance compared to other approaches. Copyright © 2008 John Wiley & Sons, Ltd.
Simultaneous prediction intervals for ARMA processes with stable innovations
Authors: Nolan John P. , Ravishanker Nalini 
Published: October 2008

AbstractWe describe a method for calculating simultaneous prediction intervals for ARMA times series with heavy‐tailed stable innovations. The spectral measure of the vector of prediction errors is shown to be discrete. Direct computation of high‐dimensional stable probabilities is not feasible, but we show that Monte Carlo estimates of the interval width is practical. Copyright © 2008 John Wiley & Sons, Ltd.
Development of New Models for Geomechanical Characterisation Using Data Mining Techniques
Authors: Miranda Tiago , Correia António Gomes , Ribeiro e Sousa Luís 
Published: October 2008

AbstractThe evaluation of geomechanical parameters for rock masses is one of the issues with largest uncertainty degree. This is mostly true in the preliminary stages of design and in small works where geotechnical information is normally scarce. In these cases, geotechnical data from past projects could help in the definition of design values for the parameters. Data Mining techniques have been successfully used in many fields. They are advanced techniques which allow to analyse large and complex databases like the ones it would be possible to build with geotechnical information. In this context, it was intended to gather a large database of geotechnical data and use these innovative tools to analyse and induce new and useful knowledge. The main goal was to develop new and reliable models to predict geomechanical parameters values mainly when only limited data is available.
The Role of Advanced Constitutive Models in Geotechnical Engineering
Authors: Schweiger Helmut F. 
Published: October 2008

AbstractNumerical calculations have a long tradition in tunnelling but in recent years numerical methods have become a standard tool for analysing a wide variety of geotechnical problems. This has become feasible because advanced constitutive models are available in commercial software packages and sufficient computer power for performing 3D nonlinear analysis is readily available. In this paper a short history of the development of constitutive models for soils will be given, starting from (non)linear elasticity to strain hardening formulations. Emphasis is put on consequences the use of different models has on the results of boundary value problems rather than on the mathematical description. The significant advances made within the last decade will be obvious. It is pointed out that this overview is directed towards practical applications and does not include models which are predominantly used in research. The merits of using advanced models in practice are discussed.
Ankerung im Untertagebau – Entwicklungen in Theorie und Praxis
Authors: Kainrath‐Reumayer Stefan , Neugebauer Erich , Charette Francois , Plouffe Michel , Galler Robert 
Published: October 2008

AbstractDie systematische Ankerung des Gebirges stellt ein wesentliches Verfahren zur Stabilisierung unterirdischer Hohlraumbauten dar. Die geschichtliche Entwicklung verschiedener Ankersysteme wird kurz vorgestellt und Unterteilungsmöglichkeiten werden aufgezeigt. Unterschiedliche Ansätze der Systemankerungen in analytischen und numerischen Berechnungen werden mit der diskreten Modellierung des Gesamtssystems in numerischen Berechnungen mit FLAC3D verglichen. Der Einfluss von Systemankerungen auf das Systemverhalten ist von einer Reihe von Randbedingungen abhängig, der Erfolg der Anwendung oftmals von den verwendeten Ankersystemen.Extreme Spannungszustände im Gebirge stellen hohe Anforderungen an die Methodik der Gebirgsankerung in Untertagebauwerken, die mit den herkömmlichen Ankerungssystemen nur eher unzufriedenstellend zu bewältigen sind. In Abhängigkeit von den Eigenschaften des Gebirges ist unter solch hohen, die Festigkeit des intakten Gebirges meist bereits überschreitenden Spannungszuständen mit großen Verschiebungen, Stabilitätsproblemen sowie Bergschlagphänomenen zu rechnen. Um diesen Anforderungen bestmöglich gerecht zu werden, wird ein neuartiger, energieabsorbierender Ankertyp “Roofex” vorgestellt, der sowohl unter langsam kriechenden, statischen, wie auch abrupten, dynamischen Beanspruchungen einen kontrollierbaren und konstanten Widerstand entlang eines definierten Gleitwegs aufweist.
The Development of the Observational Method
Authors: Schubert Wulf 
Published: October 2008

AbstractA continuous observation during construction always has been an important element of geotechnical engineering for minimizing risks. The reasons are the uncertainties in the geological and geotechnical models, as well as the limited capability to sufficiently accurately describe the complex ground behaviour. In the early days design of geotechnical structures thus was mainly based on experience. As usual, experience was used to develop mathematical solutions to the problem. To account for the inherent scatter of parameters and uncertainties in the models, the assumptions made during design had and have to be verified or falsified during construction by observations. For safe and economical construction, the design has to be adjusted during construction to the actual conditions. The term “observational method” was first formally introduced by Peck and Terzaghi. The original ideas behind the method have not always been understood or followed. After a brief historical review of the observational method the current status of the method is critically reviewed, and further developments discussed.
BEG Tunnel Fritzens – Druckluftvortrieb mit Unterstützung zweireihiger horizontaler DSV‐Schirme
Authors: Hornich Wolfgang , Geisler Hansjörg 
Published: October 2008

AbstractDie Unterquerung des Bahnhofes Fritzens in bergmännischer Sonderbauweise unter Druckluftbedingungen im Schutz einer horizontalen DSV‐Sicherung ist einer der schwierigsten und technisch anspruchsvollsten Abschnitte auf der gesamten Neubaustrecke der Unterinntaltrasse. Die besonderen Herausforderungen bei der Ausführung dieser weltweit erstmalig eingesetzten Kombination aus horizontaler DSV‐Vortriebssicherung und Druckluftvortrieb sowie die dabei gesammelten Erfahrungen sind Gegenstand dieses Beitrags.
Baupraktische Erfahrungen eines Vortriebs im Schutz eines umhüllenden Frostkörpers am Beispiel des U‐Bahnhofs Brandenburger Tor, Berlin
Authors: Müller Benno , Bayer Franz 
Published: October 2008

AbstractIn unmittelbarer Nähe zum Brandenburger Tor in Berlin‐Mitte wurde im Kreuzungsbereich Unter den Linden/Wilhelmstraße der U‐Bahnhof Brandenburger Tor überwiegend in bergmännischer Bauweise im Schutz einer Bodenvereisung erbaut. Die Arbeitsgemeinschaft, bestehend aus Hochtief Construction AG, Berlin, und Max Bögl GmbH & Co. KG, München, erhielt hierzu im Jahr 2005 den Auftrag von den Berliner Verkehrsbetrieben. In einem Alternativkonzept zur Ausschreibung wurden erstmals mit Eis gefüllte Mikrotunnel in das thermische und statische System des Frostkörpers eingebunden. Die Rohbauarbeiten wurden im Sommer 2008 abgeschlossen.
Advanced Ground Freezing at the Hallandsås Project, Sweden
Authors: Sturk Robert , Stille Björn 
Published: October 2008

AbstractAn extensive fault zone within the Hallandsås Project Sweden, a railway tunnel project in southwest of Sweden, is subject of an advanced ground freezing operation in order to facilitate TBM excavation through this section. The rock mass within the fault zone consists of a completely decomposed gneiss and amphibolite in combination with 10 to 12 bar ground water pressure. Ground freezing was carried out in 16 horizontally drilled freeze holes with a length of 100 m. Within the 10.6 m diameter final tunnel section a small 5 m diameter pilot tunnel was excavated through the frozen area. The design and execution of the freezing and excavation operations have followed the observational method. This included prediction, monitoring and follow up of all parameters associated with design of frozen ground, such as strength and creep properties, as well as design aspects on the final segmental lining installed by the TBM. By thorough project management and active design it is possible to control the involved processes and achieve a transparent methodology in predicting and executing tunnelling using the freezing method.
Das hochdruckseitige Wasserschloss des Kopswerks II – bauliche Planung, Konzeption und technische Ausführung
Authors: Wegeler Gerd , Gerstner Reinhold 
Published: October 2008

AbstractDas Pumpspeicherkraftwerk Kops II der Vorarlberger Illwerke AG (Österreich), als Parallelwerk zum bestehenden Kopswerk I, nutzt den vorhandenen Speichersee Kops als Oberwasser‐ und das Ausgleichsbecken Rifa im hinteren Montafon als Unterwasserreservoir. Durch die sehr kurzen Regelzeiten der drei Maschinensätze wird der hochdruckseitige Triebwasserweg, bestehend aus Druckschacht, Wasserschloss und Druckstollen, dynamisch stark beansprucht. Das Zweikammerdifferentialwasserschloss liegt in mehreren durch Glimmerschieferbänder getrennten Bergwasserstockwerken. Aufgrund der geologischen Verhältnisse, der Wasserschlossgeometrie und der stark schwankenden Innendruckverhältnisse wurden unterschiedliche Auskleidungsarten verwendet. In der Oberen Kammer konnte aufgrund des geringen Innendrucks eine mit Kontaktinjektionen gebettete Betonschale eingebaut werden, im Wasserschlosssteigschacht wurde eine vorgespannte, größtenteils unbewehrte Betonauskleidung verwendet. In der Unteren Kammer wurden aus verschiedenen bautechnischen Gründen sowohl Panzerungsbereiche als auch durchgehend bewehrte, mit Injektionen vorgespannte Betonauskleidungsstrecken geplant und ausgeführt.
Kopswerk II – Geologie und Felsmechanik bei Erkundung, Planung und Bauausführung der Maschinenkaverne
Authors: Netzer Elmar , Gerstner Reinhold 
Published: October 2008

AbstractDie Maschinenkaverne des Kopswerks II zählt zu den weltweit größten vergleichbaren Kavernen. Die Vorerkundungen, die geologischen Voraussetzungen und die in baugeologischer und felsmechanischer Hinsicht wesentlichen Aspekte des Kavernenausbruchs werden beschrieben. Die Erfassung der Gebirgseigenschaften, insbesondere des Trennflächengefüges, und deren richtige Vereinfachung für die felsmechanischen Berechnungen waren Voraussetzung für die Entwicklung des Ausbruchs‐ und Sicherungskonzepts. Die zutreffende Prognose der Verformungen war Bedingung für den rechtzeitigen Einbau der Maschinensätze.
BEAM – Geoelectrical Ahead Monitoring for TBM‐Drives
Authors: Kaus Arnim , Boening Wolf 
Published: October 2008

AbstractBEAM is a non‐intrusive focused‐electrical induced polarisation ground prediction technique, permanently operating while TBM tunnelling. Main components of the survey system are the measuring unit placed in the TBM operator cabin and special adapted excavation tools which are used as electrodes. The unit is connected to the guidance system and receives the boring signal which allows fully automatic data acquisition and visualisation in real‐time on an integrated monitor. Communication facilities transfer the forecast results to every accredited computer world wide simultaneously. Based on the measuring data the percentage frequency effect PFE and the resistivity R, an advanced evaluation software is established for geoelectrical‐geological/hydrogeological classification and interpretation. Selected case studies from international TBM projects are outlined with prediction results of different kinds of exploration targets and geological situations. Since 2000 the geophysical probing system is fulfilling the practical demands under the rough and various conditions of TBM tunnelling work by indicating reliable results in hard rock as well as in soft ground.