bluuebunny/crossref_metadata_2025 huggingface dataset:
Benthic and hyporheic invertebrate community responses to seasonal flow recession in a groundwater‐dominated stream
Authors: Stubbington Rachel , Wood Paul J. , Reid Ian , Gunn John
Published: October 2010

Natural hydrological variability in lotic ecosystems can include prolonged periods of flow recession. A reduction in discharge is accompanied by abiotic changes in benthic and hyporheic habitats, often including reductions in habitat availability. Whilst the benthic invertebrate community response to low flows is well documented, little research has considered how the composition of the community within the hyporheic zone is affected. We examined benthic and hyporheic invertebrate community composition during flow recession in a temperate karst stream, at sites with contrasting historic flow permanence regimes. Changes in benthic invertebrate community composition primarily reflected changes in habitat availability associated with discharge variability; in particular, the population density of the dominant amphipod, Gammarus pulex, increased as the area of submerged benthic sediments declined. Concurrent significant increases in the hyporheic abundance of G. pulex, and moderate increase in the proportion of the total G. pulex population inhabiting the hyporheic zone were recorded. It is postulated that G. pulex migrated into the hyporheic zone to reduce exposure to intensifying biological interactions in the benthic sediments. An increase in the hyporheic abundance of G. pulex was particularly pronounced at sites with historic intermittent flow, which could be attributed to downwelling stream water dominating vertical hydrologic exchange. The increase in G. pulex abundance reduced community diversity in the benthic sediments, but had no apparent detrimental effects on hyporheic invertebrate assemblages. Copyright © 2010 John Wiley & Sons, Ltd.
Effects of IFN‐α as a signal‐3 cytokine on human naïve and antigen‐experienced CD8+ T cells
Authors: Hervas‐Stubbs Sandra , Riezu‐Boj Jose‐Ignacio , Gonzalez Iranzu , Mancheño Uxua , Dubrot Juan , Azpilicueta Arantza , Gabari Izaskun , Palazon Asis , Aranguren Alicia , Ruiz Juan , Prieto Jesus , Larrea Esther , Melero Ignacio
Published: October 2010

IFN‐α/β link innate and adaptive immune responses by directly acting on naïve CD8+ T cells. This concept unveiled in mice remains unexplored in humans. To investigate that, human CD8+CD45RO− cells were stimulated with beads coated with anti‐CD3 and anti‐CD28 mAb, mimicking Ag (type‐1) and co‐stimulatory (type‐2) signals, in the presence or absence of IFN‐α and their transcriptional profiles were defined by cDNA‐microarrays. We show that IFN‐α provides a strong third signal directly to human CD8+ T cells resulting in regulation of critical genes for their overall activation. This transcriptional effect was substantiated at the protein level and verified by functional assays. Interestingly, the biological effects derived from this stimulation vary depending on the CD8+ T‐cell population. Thus, whereas IFN‐α increases the proliferative capacity of naïve CD8+ T cells, it inhibits or does not affect the proliferation of Ag‐experienced cells, such as memory and effector CTL, including CMV‐specific lymphocytes. Cytolysis and IFN‐γ‐secretion of all these populations are enhanced by IFN‐α‐derived signals, which are critical in naïve CD8+ T cells for acquisition of effector functions. Our findings in human CD8+ T cells are informative to understand and improve IFN‐α‐based therapies for viral and malignant diseases.
Modelling and Performance Evaluation of Solid Oxide Fuel Cell for Building Integrated Co‐ and Polygeneration
Authors: Kazempoor P. , Dorer V. , Ommi F.
Published: October 2010

Models of fuel cell based combined heat and power systems, used in building energy performance simulation codes, are often based on simple black or grey box models. To model a specific device, input data from experiments are often required for calibration. This paper presents an approach for the theoretical derivation of such data. A generic solid oxide fuel cell (SOFC) system model is described that is specifically developed for the evaluation of building integrated co‐ or polygeneration. First, a detailed computational cell model is developed for a planar SOFC and validated with available numerical and experimental data for intermediate and high temperature SOFCs with internal reforming (IT‐DIR and HT‐DIR). Results of sensitivity analyses on fuel utilisation and air excess ratio are given. Second, the cell model is extended to the stack model, considering stack pressure losses and the radiative heat transfer effect from the stack to the air flow. Third, two system designs based on the IT‐DIR and HT‐DIR SOFCs are modelled. Electric and CHP efficiencies are given for the two systems, as well as performance characteristics, to be used in simulations of building integrated co‐ and polygeneration systems.
Simulation and Validation of Thermo‐mechanical Stresses in Planar SOFCs
Authors: Kuebler J. , Vogt U. F. , Haberstock D. , Sfeir J. , Mai A. , Hocker T. , Roos M. , Harnisch U.
Published: October 2010

To study possible failure modes of the Hexis Galileo solid oxide fuel cell stack, various stack components such as nickel/yttria stabilised zirconia anodes, lanthanum strontium manganese cathodes, 3 mol%‐yttria stabilised zirconia electrolytes and chromium alloy metallic interconnectors have been characterised with respect to their thermo‐mechanical properties. Specifically, coefficients of thermal expansion, Young's moduli, bending strengths, Poisson's ratios and fracture toughnesses have been measured. Furthermore, the temperature‐dependent warpage of complete cells has been investigated by video analysis. All experimental data were taken as input parameters for a set of finite element models to analyse various thermo‐mechanical phenomena on different length scales. The simulations offer an explanation for the often observed ‘saddle‐like‘ deformations of cells at room temperature. They also show that cracks that first develop within the anode induce local tensile stresses within the electrolyte and hence represent a weakening mechanism for the cells. It is shown that the induced electrolyte stresses depend on the anode crack density. The electrolyte stresses decrease as the distances between the anode cracks become smaller.
Anode‐supported SOFC Operated Under Single‐chamber Conditions at Intermediate Temperatures
Authors: Morales M. , Roa J. J. , Capdevila X. G. , Segarra M. , Piñol S.
Published: October 2010

Anode‐supported SOFC was fabricated using gadolinia doped ceria (GDC) as the electrolyte (15 μm of thickness), Ni‐GDC as the anode and La0.5Sr0.5CoO3 – δ‐GDC as the cathode. Catalytic activities of the electrodes and electrical properties of the cell were determined, using mixtures of methane + air, under single‐chamber conditions. This work assessed with special and wide emphasis the effect of temperature, gas composition and total flow rate on the cell performance. As a result, operational temperature range of the fuel cell was approximately between 700 and 800 °C, which agrees with the results corresponding to the catalytic activities of electrodes. While Ni‐GDC anode was enough active towards methane partial oxidation at cell temperatures higher than 700 °C, the LSC‐GDC cathode was enough inactive towards partial and total oxidation of methane at cell temperatures lower than 800 °C. Under optimised gas compositions (CH4/O2 ratio (1) and total flow rate ((530 mL min–1), power densities of 145 and 235 mW cm–2 were obtained at 705 and 764 °C, respectively.
Swelling of sulphatic claystones – some fundamental questions and their practical relevance /
Authors: Anagnostou Georg , Pimentel Erich , Serafeimidis Konstantinos
Published: October 2010

Sulphatic claystones exhibit a heavily swelling behaviour and are among the most problematic rocks for tunnelling. Their swelling is usually attributed to the transformation of anhydrite to gypsum. The paper questions this simplistic hypothesis through a qualitative discussion of the processes underlying the phenomena that are observed macroscopically, and by identifying a series of fundamental issues that are important from the point of view of tunnel design. At the same time, it provides an overview of ongoing or recent research dealing with the swelling of sulphatic claystones and, more specifically, with the effects of chemical reactions and transport processes, the role of the clay fraction, the pressure dependence of swelling deformations and the possible effects of the seepage flow regime, including evaporation in the unsaturated zone.

Sulfathaltige Tonsteine weisen ein besonders starkes Quellverhalten auf und gehören zu den problematischsten Gesteinen beim Tunnelbau. Ihr Quellen wird üblicherweise auf die Umwandlung von Anhydrit zu Gips zurückgeführt. Der vorliegende Aufsatz diskutiert diese vereinfachende Hypothese, indem er die dem makroskopisch beobachtbaren Quellvorgang zugrundeliegenden Prozesse qualitativ behandelt und eine Übersicht über aktuelle Forschungsprojekte vermittelt. Dabei wird eine Reihe von Themen der Grundlagenforschung identifiziert, die auch von praktischer Bedeutung sind. Zu diesen gehören die Fragen nach dem Einfluss der chemischen Reaktions‐ und Transportvorgänge, der Rolle der Tonfraktion, der Druckabhängigkeit der Quellverformungen und der Bedeutung der Sickerströmung.
Gerlos power station/Gmünd dam – stabilization of a reservoir slope (Grasegger slope) /
Authors: Leobacher Alois , Blauhut Andreas
Published: October 2010

The reservoir Gmünd with a capacity of approximately 900,000 m3 is located about 10 km west of the village of Gerlos. The reservoir is connected with the power house Gerlos in the Zillertal, having a head of about 610 m. For increase of power from 65 to 200 MW the power house Gerlos was extended and the flow rate of the adapted power tunnel was raised from 14 to 42 m3/s maximum. The effect of the higher draw‐down rates on the reservoir slopes has been tested in September 2004 with a highspeed draw‐down with rates up to 5 m/h. As a result of this trial a landslide with an estimated volume of 10,000 m3 occurred on the Graseggerhang. The landslide showed the necessity of an effective slope stabilization of the Graseggerhang for a continuous unlimited reservoir management in the future. After a comprehensive investigation it was decided to build in a supporting fill, consisting of rock mass of a maximum grain size of 65 cm. The support fill wit h a volume of about 100,000 m3 was built in from October to December 2006 and the operation of the power plant Gerlos II started directly afterwards. For the long term surveillance of the support fill one inclinometer and several geodetic measuring points have been installed.

Der Speicher Gmünd mit einem Speicherinhalt von ca. 900.000 m3 liegt etwa 10 km westlich der Ortschaft Gerlos. Über das im Zillertal gelegene Kraftwerk Gerlos wird dieser Speicher mit einer Fallhöhe von ca. 610 m abgearbeitet. Zur Umsetzung einer Leistungserhöhung von 65 auf 200 MW wurde das Krafthaus Gerlos erweitert und mit einer angepassten Triebwasserleitung die Abbauwassermenge von 14 auf maximal 42 m3/s erhöht. Zur Untersuchung der Auswirkungen der daraus resultierenden höheren Absenkgeschwindigkeiten wurde im September 2004 ein Schnellabsenkversuch mit maximalen Absenkraten von bis zu 5 m/h durchgeführt. Im Zuge der Staulegung wurde eine Rutschung mit einem geschätzten Volumen von ca. 10.000 m3 am Graseggerhang ausgelöst. Daher wurden umgehend Überlegungen für eine wirkungsvolle Sanierungsmaßnahme der betroffenen Speicherböschung angestellt, um auch zukünftig eine uneingeschränkte Speicherbewirtschaftung zu garantieren. Nach einer umfassenden Untersuchung wurde als Sanierungsvariante eine Stützschüttung bestehend aus Felsmaterial mit einem Größtkorn von 65 cm ausgewählt. Die Stützschüttung mit einem Volumen von rund 100.000 m3 wurde von Oktober bis Dezember 2006 eingebaut und daran anschließend der Kraftwerksbetrieb wieder aufgenommen. Für die Langzeitüberwachung der Stützschüttung wurden ein Inklinometer sowie mehrere geodätische Messpunkte installiert.
The interaction of machine and rock mass analysed using TBM data and rock mass parameters /
Authors: Poisel Rainer , Tentschert Ewald , Preh Alexander , Ostermann Viktoria , Chwatal Werner , Zettler Alfred
Published: October 2010

Statistical investigations of TBM data and rock parameters have shown that interactions determined theoretically or in the laboratory are often not realistic because the interaction of the machine with the rock mass is considerably influenced by the type of machine in use, the machine driver and the characteristics of the rock mass. Evaluations of excavation data have shown that the maximum net advance rate is not produced by the maximum thrust force, even in the same rock type. Individualised optimisation of the interaction on the basis of continuously recorded machine data and basic information about the rock mass (type of rock, degree of jointing), which can be determined by geological and geophysical investigations during tunnelling, is therefore of particular significance for economical tunnelling. The evaluation of these data should not replace but rather supplement the control of the machine by the driver.

Die statistischen Untersuchungen von TBM‐Daten und Gebirgskennwerten haben gezeigt, dass im Labor oder theoretisch ermittelte Zusammenhänge in der Realität oft nicht gegeben sind, weil die Interaktion Maschine‐Gebirge stark von der eingesetzten Maschine, der Fahrweise des Maschinenführers und dem jeweiligen Gebirge beeinflusst wird. So haben Auswertungen von Vortriebsdaten gezeigt, dass auch in der gleichen Gebirgsart die maximale Nettovortriebsgeschwindigkeit nicht bei maximaler Anpresskraft auftritt. Der individuellen Optimierung der Interaktion auf Basis von laufend erhobenen Maschinendaten und von Basisinformationen über das Gebirge (Gesteinsart, Zerlegungsgrad), die durch geologische und geophysikalische Untersuchungen während des Vortriebs erhalten werden können, kommt daher in Bezug auf einen wirtschaftlichen Vortrieb besondere Bedeutung zu. Die Auswertung dieser Daten soll die Steuerung durch den Maschinenführer nicht ersetzen sondern unterstützen.
The exploitation of warm tunnel water through the example of the Lötschberg Base Tunnel in Switzerland /
Authors: Hufschmied Peter , Brunner Andreas
Published: October 2010

The drainage of the north side of the Lötschberg Base Tunnel in the Bernese Oberland in Switzerland continuously produces about 100 litres of water per second at about 20 °C. This water is discharged into the local river Kander. In order to protect wetland areas and water rights, the responsible authorities imposed limitations on the quantity of drainage from the tunnel. At the same time, the warming of the Kander by the discharged groundwater has to be limited to 0.5 °C to protect the lake trout from the Thunersee lake, which swim up the Kander to spawn. Particularly in the cold winter months when the water flow in the Kander is low, this requires the withdrawal of about 4 MW of thermal energy, or the cooling of the groundwater by about 10 °C. Instead of artificial cooling, the Tropenhaus Frutigen in combination with a local heating network exploits the warm groundwater for sturgeon farming together with tropical green houses. A high added value is achieved through sustainable use with polycultures, closed circulations and the use of alternative energies. The project has aroused great interest nationally and internationally.

Der Lötschberg‐Basistunnel im Schweizerischen Berner Oberland dräniert auf seiner Nordseite kontinuierlich rund 100 Liter pro Sekunde etwa 20 °C warmes Bergwasser. Dieses Wasser wird in das lokale Fließgewässer, die Kander, eingeleitet. Zum Schutz von Feuchtgebieten und Wasserrechten haben die Behörden die Dränagemenge des Tunnels limitiert. Gleichzeitig musste zum Schutz der Seeforellen aus dem Thunersee, die in die Kander zum Laichen aufsteigen, die Erwärmung der Kander als Folge des eingeleiteten Bergwassers auf 0,5 °C begrenzt werden. Insbesondere in den kalten Wintermonaten mit Niedrigwasser in der Kander erforderte dies den Entzug von rund 4 MW thermischer Energie bzw. eine Abkühlung des Bergwassers um rund 10 °C. An Stelle einer künstlichen Abkühlung nutzt das Tropenhaus Frutigen in Kombination mit einem Nahwärmeverbund das warme Bergwasser in einer mit tropischen Gewächshäusern kombinierten Störzucht. Dank einer nachhaltigen Nutzung mit Polykulturen, geschlossenen Kreisläufen und dem Einsatz von erneuerbarer Energie wird ein hoher Mehrwert erzielt. Das Projekt stößt damit sowohl national als auch international auf großes Interesse.
The interaction of ground, TBM and segment lining with closed shield machines /
Authors: Göbl Arthur
Published: October 2010

The article explains the interaction of the overall system of ground, TBM and segment lining based on recent experience of projects using TBMs with active face support in Austria and abroad. The alternating dependencies and their consequences for tunnel construction are discussed in more detail. Of particular interest is the influence of the support medium and how it functions at the face and the tunnel side walls. The interaction of support pressure, thrust force and the centre of gravity of the TBM and its effect on steering behaviour are also considered. The effects of the compression of the segment tube by the TBM (prestress) are considered in relation to the improvement of the bedding and the problem of floating.

Der Beitrag beleuchtet die Interaktion des Gesamtsystems “Untergrund – Tunnelvortriebsmaschine – Tübbingausbau” basierend auf aktuellen Erfahrungen zuletzt realisierter Projekte im In‐ und Ausland bei TVM‐Einsätzen mit aktiver Ortsbruststützung. Dabei wird insbesondere auf die wechselweisen Abhängigkeiten und deren Auswirkungen auf die Tunnelherstellung eingegangen. Ein Schwerpunkt liegt beim Einfluss des Stützmediums und der zugehörigen Wirkungsweise an der Ortsbrust und der Tunnellaibung. Berücksichtigung findet die Wechselwirkung von Stützdruck, Vortriebskraft und der Schwerpunktlage der TVM auf deren Steuerverhalten. Die Auswirkung des Zusammendrückens der Tübbingröhre durch die TVM (Vorspannung) wird in Bezug auf die Bettungsverbesserung und die Problematik des Aufschwimmens betrachtet.
Tunnelling in swelling rock – a solved problem? /
Authors: Zettler Alfred , Poisel Rainer , Preh Alexander , Konietzky Heinz
Published: October 2010

In some sedimentary rocks, the admission of water results in an expansion of volume, which results from the chemical conversion of anhydrite into gypsum (anhydrite swelling) or the physical adsorption of water in certain clay minerals (clay swelling). This expansion leads to heavy loading of the tunnel lining and has already caused significant damage to some structures. In addition, sulphate attack on the lining concrete can lead to softening due to the formation of ettringite. Damage can be in the form of shear failure, spalling or bending tension cracks. The location and nature of the damage, which depends on the location of the ground containing clay or anhydrite and susceptible to swelling, is illustrated with some examples. Numerical modelling is applied to demonstrate the load transfers, which lead to these phenomena. Recent attempts to counter the problem have been based on the strengthening of the lining (resistance principle) or by installing compressible zones between rock mass and lining (yielding principle). The design rules for each principle are explained.

Bei einigen Sedimentgesteinen ereignet sich bei Wasserzutritt eine Volumenzunahme, die eine Folge der chemischen Umwandlung von Anhydrit in Gips (Schwellen) oder der physikalischen Anlagerung von Wasser an bestimmte Tonminerale (Quellen) ist. Diese Volumenzunahme führt zu starken Beanspruchungen der Tunnelauskleidung und hatte bei einigen Bauwerken bedeutende Schäden zur Folge. Darüber hinaus führt ein möglicher Sulfatangriff auf den Auskleidungsbeton zur Entfestigung durch Ettringitbildung. Diese Schäden können Scherbrüche, Abplatzungen und Biegezugrisse sein. Ort und Art der Schäden in Abhängigkeit vom Ort der quellenden bzw. schwellenden Gebirgsbereiche werden anhand einiger Beispiele aufgezeigt. Mittels numerischer Untersuchungen wird ein Einblick in die Lastumlagerungen gegeben, die zu den genannten Phänomenen führen. In neuerer Zeit wurde versucht, den Schäden einerseits durch eine Verstärkung der Auskleidung (Widerstandsprinzip) und andererseits durch nachgiebige Zonen zwischen Gebirge und Ausbau (Nachgiebigkeitsprinzip) zu begegnen. Die Entwurfsgrundsätze für diese Prinzipien werden dargelegt.
Chienberg Tunnel: Rehabilitation using yielding elements of the section in Keuper sediments affected by heave /
Authors: Chiaverio Flavio , Thut Arno
Published: October 2010

Rocks containing clay and anhydrite exhibit the property of increasing their volume by absorbing water. The paper first discusses the mechanisms causing swelling and outlines their effects on tunnels. Next the hazard scenario of heaving of the tunnel tube as a whole, the structural consequences of this and the concept of the Modular Yielding System for tunnelling in stretches where heave is unavoidable are discussed. Taking the case of the Chienberg road tunnel in Switzerland, the paper also reports on experience during construction and field measurements after putting the repaired sections into operation. Special attention is given to the technical aspects of yielding supports with cement as a basic constituent for loads up to 10 MN and a yielding capacity of up to 50 %.

Ton‐ und anhydritführende Gesteine haben die Eigenschaft, ihr Volumen durch Aufnahme von Wasser zu vermehren. Der Beitrag behandelt einleitend die Mechanismen, die den Quellvorgang auslösen und die Auswirkungen des Quellvorgangs auf Tunnel. Anschließend wird das Gefährdungsbild der Hebungen der Tunnelröhre als Ganzes, deren Folgen auf die Tragkonstruktion und das Konzept des modularen Knautschsystems] für den Tunnelbau in unvermeidbaren Hebungsstrecken erörtert. Am Beispiel des Chienbergtunnels in der Schweiz wird auch über Bauerfahrung und Feldmessungen nach der Inbetriebnahme der sanierten Strecken berichtet. Besondere Aufmerksamkeit wird den technischen Merkmalen von Knautschkörpern auf Zementbasis für Belastungen von bis zu 10 MN und einem Stauchvermögen von bis zu 50 % gewidmet.
A9 Bosruck Tunnel – design approaches for swelling rock /
Authors: Lenz Franz , Marcher Thomas , Neumayr Thomas
Published: October 2010

Construction works were started for the 2nd tube of the Bosruck road tunnel on the A9 Pyhrn motorway in December 2009, as part of the ongoing upgrade to full motorway standard by ASFINAG. In the course of the more than 100‐year history of tunnelling under the Grosse Bosruck, this tunnel is the fourth tunnel to be built in this part of the central mountain range of the Eastern Alps. The 4,766 m long single‐track railway tunnel was constructed between 1901 and 1906, the ventilation and drainage tunnel for the road tunnel between 1978 and 1980, and the approximately 5,500 m long road tunnel for two‐way traffic was constructed between 1980 and 1983.

Soon after being opened for traffic, substantial damage became apparent in the road tunnel. It was only possible to maintain operation by means of continuous and costly rehabilitation measures. In 2005, the extent of damage finally led to the decision to add a second tube to the road tunnel and to carry out a general rehabilitation of the existing tube of the road tunnel. The main conclusions regarding the swelling and squeezing behaviour drawn from the damage that had occurred in the first tube of the road tunnel were exploited for the design and construction of the second tube and are the subject of this paper.

Im Dezember 2009 wurde im Rahmen des laufenden Vollausbauprogramms der ASFINAG mit den Bauarbeiten für die zweite Röhre des Bosruck Straßentunnels der A9 Pyhrn Autobahn begonnen. Dabei handelt es sich in der über hundertjährigen Geschichte des Tunnelbaues am großen Bosruck um den vierten Tunnel, der in diesem Abschnitt des Ostalpenhauptkamms errichtet wird. Der eingleisige 4.766 m lange Eisenbahntunnel wurde 1901 bis 1906, der Lüftungs‐ und Entwässerungsstollen für den Straßentunnel 1978 bis 1980 und die 5.500 m lange Oströhre des Straßentunnels 1980 bis 1983 errichtet. Bald nach der Inbetriebnahme kam es im Straßentunnel zu massiven Schäden. Der Betrieb konnte nur durch aufwändige laufende Sanierungsmaßnahmen aufrecht erhalten werden. Der Schadensverlauf führte letztendlich im Jahr 2005 zur Entscheidung des vorzeitigen Vollausbaus und der anschließenden Generalsanierung der bestehenden Röhre des Straßentunnels. Die wesentlichen geomechanischen Schlüsse hinsichtlich des quellenden und druckhaften Gebirgsverhaltens, die aus den Schadensbildern der ersten Röhre des Straßentunnels für die Errichtung der zweiten Röhre gezogen werden können, sind Gegenstand dieses Beitrags.
Postoperative myocardial injury after major head and neck cancer surgery
Authors: Nagele Peter , Rao Lesley K. , Penta Mrudula , Kallogjeri Dorina , Spitznagel Edward L. , Cavallone Laura F. , Nussenbaum Brian , Piccirillo Jay F.
Published: October 2010

Background.

Patients with head and neck cancer often have multiple risk factors for coronary artery disease. Yet, little is known about the incidence of postoperative myocardial injury after major head and neck cancer surgery and its clinical relevance. The aim of this study was to determine the risk of postoperative myocardial injury in patients undergoing major head and neck cancer surgery.

Methods.

This was a retrospective cohort study of all patients who underwent major head and neck cancer surgery (n = 378) at a single major academic center from April 2003 to July 2008. Peak postoperative troponin I (TnI) concentration was the primary outcome.

Results.

Of 378 patients who underwent major head and neck cancer surgery, 57 patients (15%) had development of an elevated TnI; 90% of these occurred within the first 24 hours after surgery. Preexisting renal insufficiency (unadjusted OR [OR]: 4.60; 95% CI 1.53–13.82), coronary artery disease (OR: 2.33; 95% CI 1.21–4.50), peripheral vascular disease (OR: 2.83; 95% CI 1.31–6.14), hypertension (OR: 2.22; 95% CI 1.20–4.12), and previous combined chemotherapy and radiation (OR: 2.68; 95% CI 1.04–6.91) were associated with elevated postoperative TnI levels. Patients with elevated TnI levels had a significantly longer length of stay in the hospital (8.5 vs 10.1 days; p = .014) and ICU (3 vs 4.5 days; p = .001) and an 8‐fold increased risk of death at 60 days after surgery (adjusted OR: 8.01, 95% CI 2.03–31.56). At 1 year, patients with an abnormal postoperative TnI level were twice as likely to die (OR 1.93; 95% CI 1.02–3.63).

Conclusions.

Patients who undergo major head and neck cancer surgery are at significant risk for postoperative myocardial injury, which is a strong predictor of 60‐day mortality after surgery. Monitoring of myocardial injury during the first postoperative days, as well as optimizing preventive cardiac care, may be helpful to reduce postoperative mortality rates. Head Neck, 2011
Warnings in manufacturing: Improving hazard‐mitigation messaging through audience analysis
Authors: Goldsworthy Richard C. , Mayhorn Christopher B. , Meade Adam W.
Published: October 2010

Hazard mitigation, including warning development, validation, and dissemination, is an important aspect of product safety and workplace and consumer protection. Understanding our audiences—workers and consumers—is an especially important, often overlooked, aspect of risk and harm reduction efforts. In this article, particular attention is paid to audience analysis in hazard communication and warning messaging, with a focus on the potential role of latent class analysis (LCA). We provide an example of using LCA to analyze a hazardous behavior: prescription medicine sharing and borrowing. Four distinct groups of people—ranging from abstainers to at‐risk sharers—are identified and discussed. Building better warnings and risk communication techniques is essential to promoting occupational and consumer safety. Audience analysis is a vital component of these efforts. LCA appears to be a worthwhile addition to our analytical toolbox by allowing risk reduction and hazard‐mitigation efforts to tailor interventions to a diverse target audience. © 2010 Wiley Periodicals, Inc.
A new semiempirical kinetic method for the determination of ion exchange constants for counterions of cationic micelles: Study of the rate of pH‐independent hydrolysis of phthalimide as the kinetic probe
Authors: Khan M. Niyaz , Sinasamy Sharmilah
Published: October 2010

Pseudo‐first‐order rate constants (kobs) for pH‐independent hydrolysis of phthalimide (1), obtained at a constant total concentration of cetyltrimethylammonium bromide and hydroxide ([CTABr]T), 2.0 × 10−4 M 1, 0.02 M MOH (M+ = Li+, Na+ and K+) and various concentrations of inert salt MX (= LiCl, LiBr, NaCl, NaBr, KCl and KBr), follow a relationship derived from the pseudophase micellar (PM) model coupled with an empirical equation. This relationship gives empirical constants, FX/S and KX /S, with S representing anionic 1. The magnitude of FX/S is the measure of the fraction of micellized anionic 1 (S−M) transferred to the aqueous phase by the limiting concentration of X−. The value of KX/S is the measure of the ability of the counterions (X−) to expel the reactive counterions (S−) from the cationic micellar surface to the aqueous phase. The values of FX/ S are ∼ 1 for MBr (M+ = Li+, Na+ and K+) and in the range ⩽ 0.7 to ⩾ 0.5 for MCl (M+ = Na+ and K+) at 0.006, 0.010 and 0.016 M CTABr. For LiCl, the values of FX/S become ∼1 at 0.006 and 0.010 M CTABr and 0.8 at 0.016 M CTABr. The values of the empirical constants, FX/S and KX/S, have been used to determine the usual ion exchange constant (KClBr). The mean values of KClBr are 3.9 ± 0.5, 2.7 ± 0.1, and 2.6 ± 0.3 for LiX, NaX, and KX, respectively. These values of KClBr are comparable with those obtained directly by other physicochemical techniques. Thus, this new method for the determination of ion exchange constants for various counterions of cationic micelles may be considered as a reliable one. © 2010 Wiley Periodicals, Inc. Int J Chem Kinet 43: 9–20, 2011
Permanent magnet assembly producing a strong tilted homogeneous magnetic field: towards magic angle field spinning NMR and MRI
Authors: Sakellariou Dimitris , Hugon Cédric , Guiga Angelo , Aubert Guy , Cazaux Sandrine , Hardy Philippe
Published: October 2010

We introduce a cylindrical permanent magnet design that generates a homogeneous and strong magnetic field having an arbitrary inclination with respect to the axis of the cylinder. The analytical theory of 3 D magnetostatics has been applied to this problem, and a hybrid magnet structure has been designed. This structure contains two magnets producing a longitudinal and transverse component for the magnetic field, whose amplitudes and homogeneities can be fully controlled by design. A simple prototype has been constructed using inexpensive small cube magnets, and its magnetic field has been mapped using Hall and NMR probe sensors. This magnet can, in principle, be used for magic angle field spinning NMR and MRI experiments allowing for metabolic chemical shift profiling in small living animals. Copyright © 2010 John Wiley & Sons, Ltd.
Magnetization transfer ratio mapping of intervertebral disc degeneration
Authors: Wang Chenyang , Witschey Walter , Goldberg Ari , Elliott Mark , Borthakur Arijitt , Reddy Ravinder
Published: October 2010

The magnetization transfer ratio of the lumbar discs was spatially quantified from age‐matched subjects and the nucleus pulposus magnetization transfer ratio was correlated with T2‐weighted Pfirrmann grades. A moderate and significant linear correlation between magnetization transfer ratio and Pfirrmann grades was observed, suggesting that nucleus pulposus collagen relative density increases with degeneration. High‐resolution axial magnetization transfer ratio maps revealed elevated magnetization transfer ratio in the nucleus pulposa of injured and heavily degenerated discs. In the injured disc, significant elevation in nucleus pulposa magnetization transfer ratio was not accompanied by significant decrease in disc height. This observation may suggest a possible increase in absolute collagen content, in addition to increased collagen relative density. In summary, magnetization transfer MRI of the disc may serve as a noninvasive diagnostic tool for disc degeneration, in addition to other MRI techniques specific to proteoglycan content. Magn Reson Med, 2010. © 2010 Wiley‐Liss, Inc.
Low‐power adiabatic sequences for in vivo localized two‐dimensional chemical shift correlated MR spectroscopy
Authors: Andronesi Ovidiu C. , Ramadan Saadallah , Mountford Carolyn E. , Sorensen A.Gregory
Published: October 2010

Novel low‐power adiabatic sequences are demonstrated for in vivo localized two‐dimensional correlated MR spectroscopy, such as correlated spectroscopy and total correlated spectroscopy. The design is based on three new elements for in vivo two‐dimensional MRS: the use of gradient modulated constant adiabaticity GOIA‐W(16,4) pulses for (i) localization (correlated spectroscopy and total correlated spectroscopy) and (ii) mixing (total correlated spectroscopy), and (iii) the use of longitudinal mixing (z‐filter) for magnetization transfer during total correlated spectroscopy. GOIA‐W(16,4) provides accurate signal localization, and more importantly, lowers the SAR for both total correlated spectroscopy mixing and localization. Longitudinal mixing improves considerably (fivefolds) the efficiency of total correlated spectroscopy transfer. These are markedly different from previous 1D editing total correlated spectroscopy sequences using spatially nonselective pulses and transverse mixing. Fully adiabatic (adiabatic mixing with adiabatic localization) and semiadiabatic (adiabatic mixing with nonadiabatic localization) methods for two‐dimensional total correlated spectroscopy are compared. Results are presented for simulations, phantoms, and in vivo two‐dimensional spectra from healthy volunteers and patients with brain tumors obtained on 3T clinical platforms equipped with standard hardware. To the best of our knowledge, this is the first demonstration of in vivo adiabatic two‐dimensional total correlated spectroscopy and fully adiabatic two‐dimensional correlated spectroscopy. It is expected that these methodological developments will advance the in vivo applicability of multi(spectrally)dimensional MRS to reliably identify metabolic biomarkers. Magn Reson Med, 2010. © 2010 Wiley‐Liss, Inc.
Computational fluid dynamics applied to the aerodynamic design of a land‐based supersonic vehicle
Authors: Evans B.J. , Hassan O. , Jones J.W. , Morgan K. , Remaki L.
Published: October 2010

The BLOODHOUND SSC project was publicly announced in October 2008, with a primary engineering objective of designing, constructing and running a vehicle capable of achieving a speed of 1000 mph on land. The aerodynamic design of this vehicle is to be accomplished using computational simulation only and this paper describes the development and application of the approach adopted. The computational model employs a cell vertex finite volume algorithm for the solution of compressible viscous flow problems on unstructured hybrid meshes. A one equation turbulence model is adopted and the solution of the steady flow equations is obtained by explicit relaxation. For the combination of high Mach number, complex geometry and complex boundary conditions, involving rotating surfaces and a rolling ground, a consistent HLLC numerical flux function is adopted to ensure a stable procedure. To illustrate the impact of the approach upon the final configuration, a number of simulations undertaken to aid the aerodynamic design are described. © 2010 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2010
Do quality perceptions of health and social services vary for different ethnic groups? An empirical investigation
Authors: Bandyopadhyay Subir K. , Pardasani Manoj
Published: October 2010

The United States is now more ethnically diverse than any other time in its history. In 2000, minority ethnic groups comprised 26% of the US population; by 2010, they comprise 35%, and in 2080 they will form the majority of American citizens. And among these ethnic groups, African Americans (12.4%), Hispanics (15.4%) and Asians (4.4%) were the most predominant in 2000.

The growth of this segment of the population is not only in terms of numbers but also in terms of economic development. Minority groups are showing marked improvement in income and education levels leading to greater purchasing power. As a result, for‐profit companies are increasingly targeting minority populations with products and promotions specifically designed for specific minority groups. Even non profit organizations such as educational programs, social service and healthcare agencies are striving to design specific services and culturally competent outreach models in order to serve this increasingly diverse marketplace. But despite the strides made by non profit agencies, several studies note the tremendous disparities between the ethnic and racial groups in the seeking and the receipt of health‐care and social services. Additionally, there is limited empirical information about the perceptions of minority consumers. In order to effectively serve minority groups, it is essential to understand their experiences with the non profit service industry and to assess their ongoing concerns.

In this study, we focus on two critical components of the non profit world – healthcare and social services. We conducted a survey to compare and contrast the social service and health‐care quality perceptions of three ethnic groups: Caucasians, African‐Americans and Hispanics. Our study, undertaken in collaboration with community health centers, reveals distinct differences in perceptions between the three ethnic groups. Based on our findings, we outline a set of implementable strategies for social service and community health organizations. Copyright © 2010 John Wiley & Sons, Ltd.
“Music to our ears”: understanding why Canadians donate to arts and cultural organizations
Authors: Barnes Martha L.
Published: October 2010

The contribution of donations and volunteer time to North American arts and cultural organizations is impressive. Growing economic uncertainty coupled with the increasingly competitive nature of philanthropic work and fluctuating volunteerism rates describe some of the challenges facing nonprofit managers in the arts and cultural field today. The intent of this study was to explain charitable giving to an arts and cultural organization in a Canadian context using variables supported in the literature related to philanthropic behavior. The variables included the norm of social responsibility, donor benefits, philanthropic behavior, and household income. Data (233 questionnaires) were collected at a renowned community symphony with revenue from various sources including over $1 million annually in private support. Multiple regression analysis determined two of the four hypotheses were supported and two were partially confirmed. While the norm of social responsibility and household income did confirm existing literature, philanthropic behavior seemed only defined by length of time as donor rather than by volunteering for arts and cultural organizations and donor benefits included tax incentives but not receiving a “gift” in exchange for a support. Research such as this, which contributes to our understanding of arts and cultural donors and the benefits they seek, continues to be important with the potential to inform nonprofit managers. Copyright © 2010 John Wiley & Sons, Ltd.
Prioritized constraint handling NMPC using Volterra series models
Authors: Aliyev T. L. , Gatzke E. P.
Published: October 2010

This paper presents a nonsquare Nonlinear Model Predictive Control (NMPC) formulation that uses prioritized soft output constraints and hard input constraints. The proposed method uses empirical Volterra series models to represent the plant dynamics and is a closed loop tested on multivariable refinery facility simulation. The process exhibits significant open‐loop nonlinearity such as input steady‐state multiplicity and nonlinear dynamics near the nominal operating point. The results show improvement when compared with traditional linear control methods. Copyright © 2010 John Wiley & Sons, Ltd.
Quantitative proteomic analysis of A549 cells infected with human respiratory syncytial virus subgroup B using SILAC coupled to LC‐MS/MS
Authors: C. Munday Diane , Hiscox Julian A. , Barr John N.
Published: October 2010

Human respiratory syncytial virus (HRSV) is a leading cause of serious lower respiratory tract infections in infants. The virus has two subgroups A and B, which differ in prevalence and (nucleotide) sequence. The interaction of subgroup A viruses with the host cell is relatively well characterized, whereas for subgroup B viruses it is not. Therefore quantitative proteomics was used to investigate the interaction of subgroup B viruses with A549 cells, a respiratory cell line. Changes in the cellular proteome and potential canonical pathways were determined using SILAC coupled to LC‐MS/MS and Ingenuity Pathway Analysis. To reduce sample complexity and investigate potential trafficking both nuclear and cytoplasmic fractions were analyzed. A total of 904 cellular and six viral proteins were identified and quantified, of which 112 cellular proteins showed a twofold or more change in HRSV‐infected cells. Data sets were validated using indirect immunofluorescence confocal microscopy on independent samples. Major changes were observed in constituents of mitochondria including components of the electron transport chain complexes and channels, as well as increases in the abundance of the products of interferon‐stimulated genes. This is the first quantitative proteomic analysis of cells infected with HRSV‐subgroup B.
Translationally optimal codons associate with aggregation‐prone sites in proteins
Authors: Lee Yaelim , Zhou Tong , Tartaglia Gian Gaetano , Vendruscolo Michele , Wilke Claus O.
Published: October 2010

We analyze the relationship between codon usage bias and residue aggregation propensity in the genomes of four model organisms, Escherichia coli, yeast, fly, and mouse, as well as the archaeon Halobacterium species NRC‐1. Using the Mantel–Haenszel procedure, we find that translationally optimal codons associate with aggregation‐prone residues. Our results are qualitatively and quantitatively similar to those of an earlier study where we found an association between translationally optimal codons and buried residues. We also combine the aggregation‐propensity data with solvent‐accessibility data. Although the resulting data set is small, and hence statistical power low, results indicate that the association between optimal codons and aggregation‐prone residues exists both at buried and at exposed sites. By comparing codon usage at different combinations of sites (exposed, aggregation‐prone sites versus buried, non‐aggregation‐prone sites; buried, aggregation‐prone sites versus exposed, non‐aggregation‐prone sites), we find that aggregation propensity and solvent accessibility seem to have independent effects of (on average) comparable magnitude on codon usage. Finally, in fly, we assess whether optimal codons associate with sites at which amino acid substitutions lead to an increase in aggregation propensity, and find only a very weak effect. These results suggest that optimal codons may be required to reduce the frequency of translation errors at aggregation‐prone sites that coincide with certain functional sites, such as protein–protein interfaces. Alternatively, optimal codons may be required for rapid translation of aggregation‐prone regions.
Knowledge-Salvage Practices for Dormant R&D Projects
Authors: Tukel Oya I. , Kremic Tibor , Rom Walter O. , Miller Richard J.
Published: October 2010

Most successful firms have an abundance of new and old knowledge in their research and development laboratories, and only a fraction is being put into use in new product development. This knowledge is left over from projects that have been killed at different development stages and may actually carry considerable value. In this article, we propose a knowledge bank as a possible solution to preserve and possibly grow this knowledge. It is a self-sustaining institute with minimal or no ongoing effort from the donor company, yet manages the knowledge in a way that protects proprietary interests and actively fosters communication and interchange among sponsoring companies wherever possible. The framework of this structure, as well as how it works, is described here. Specifically, a system dynamics modeling of the knowledge bank is developed, and a simulation study is conducted using VENSIM®. The results confirm the viability of creating such a system in a consortium of organizations.
Cyclic homo and block copolymers through sequential double click reactions
Authors: Durmaz Hakan , Dag Aydan , Hizal Gurkan , Tunca Umit
Published: October 2010

Well‐defined linear α‐anthracene‐ω‐maleimide functionalized polystyrene (l‐Anth‐PS‐MI) and linear α‐alkyne‐ω‐maleimide functionalized poly(tert‐butyl acrylate) (l‐alkyne‐PtBA‐MI) homopolymers, and linear α‐anthracene‐ω‐maleimide functionalized PS‐b‐PtBA (l‐Anth‐PS‐b‐PtBA‐MI) and linear α‐anthracene‐ω‐maleimide functionalized PS‐b‐poly(ε‐caprolactone) (PCL) (l‐Anth‐PS‐b‐PCL‐MI) block copolymers were obtained via combination of atom transfer radical polymerization (ATRP)/ring opening polymerization (ROP) and azide‐alkyne click reaction strategy. Subsequently, these linear homo and block copolymers were efficiently clicked via Diels‐Alder reaction to give their corresponding cyclic homo and block copolymers at reflux temperature of toluene for 48 h under 7–4 × 10−5 M conditions. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010
Thioxanthone–carbazole as a visible light photoinitiator for free radical polymerization
Authors: Yilmaz Gorkem , Tuzun Alev , Yagci Yusuf
Published: October 2010

A thioxanthone (TX) derivative with the additional carbazole chromophore, namely thioxanthone‐carbazole (TX‐C) was synthesized and characterized. The photophysical properties and its efficiency to polymerize methyl methacrylate both in the presence and absence of N,N‐dimethylaniline (DMA) as coinitiator was investigated and compared with that of the commercially available TX. TX‐C was found to display better photophysical properties and in both cases initiate polymerization more efficiently. Detailed real‐time Fourier transform infrared studies revealed that high polymerization rates can be obtained when TX‐C in conjunction with DMA was used. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010