bluuebunny/crossref_metadata_2025 huggingface dataset:
Zur Abschätzung der charakteristischen Funktion einer Summe zufälliger Vektoren
Authors: Paditz Ludwig
Published: April 2007

Ausgangspunkt der Betrachtungen sind Fehlerabschätzungen im mehrdimensionalen zentralen Grenzwertsatz, die auf dem bekannten LJAPUNOV‐BruchLnbasieren. Bei der Ableitung derartiger Fehlerschranken wird von der grundlegenden FallunterscheidungLn≦ δk(s. (3)) undLn> δk(s. 12) ausgegangen. Nach einer Diskussion verschiedener in der Literatur benutzter Größen δk(.)(s. (16), (17)) werden für den FallLn≦ δk(Satz 1) undLn< ∞ (Sätze 2 und 3) Fehlerabschätzungen für die Differenz von charakteristischen Funktionen, die bei den Untersuchungen zum zentralen Grenzwertsatz auftritt, abgeleitet. Die dabei auftretenden absoluten Konstanten werden genau bestimmt. Es ergeben sich Verallgemeinerungen bekannter Abschätzungen für die charakteristische Funktion einer Summe unabhängiger Zufallsgrößen bzw. zufälliger Vektoren.
S‐Regular and S‐Normal Spaces
Authors: Dorsett Charles
Published: April 2007

In this paper s‐regular and s‐normal spaces are characterized using semi‐T0‐identification spaces, topological sums of s‐regular and s‐normal spaces are examined, and the relationships between s‐regular, s‐normal, and other separation axioms are further examined.
Topologies of the Hyperspace which Are Induced by Extension Spaces
Authors: Schmidt Hans‐Jürgen
Published: April 2007

The hyperspace of all nonvoid closed subsets of a topological space will be topologized by means of different methods; each of them generalizes known definitions of special hyperspace topologies. One method uses the VIETORIS topology in the hyperspaces of certain extension spaces. Another one uses certain systems of closed subsets and leads to just the same class of hyperspace topologies. In natural order VIETORIS topology is the supremum of this class, and for locally compact spaces FLACHSMEYER topology is the infimum of this class.
Hyperbolicity of Closed Orbits Determined by One Function
Authors: Langer O.
Published: April 2007

Flows on Rn are considered whose vector fields can be represented by a composition Rn→R1→Rn. Thus these vector fields and flows are determined by elements of Cr(Rn, R) × Cr(R, Rn). Vector fields of this and similar kind occur in ecological models. In general these flows have no rest point. We consider the problem how general is the property that closed orbits are hyperbolic and therefore stable under perturbations of the vector field. It is shown that in the restricted class of the vector fields described above generically all closed orbits are hyperbolic. This means that the theorem of KUPKA and SMALE holds partielly in this situation.
Gleichverteilungseigenschaften von Zufallsvariablen
Authors: Stadje Wolfgang
Published: April 2007

We prove some equidistribution results for the expansion of random variables with respect to a given basis m.
Über eindimensionale Elemente linearer Algebren und einige algebraische Eigenschaften eines elementaren Operators
Authors: Synnatzschke J.
Published: April 2007

Eindimensionale Operatoren als einfachste Elemente wichtiger umfassenderer Operatorenklassen wurden bisher auf mehrere Weisen abstrakt für verschiedene Kategorien von Algebren definiert. wir greifen hieraus auf den Begriff des eindimensionalen Elementes zurück. In § 1 werden einige einfache Eigenschaften eindimensionaler Elemente aufgeführt. In § 2 werden lineare Algebren betrachtet, deren Menge eindimensionaler Elemente in einem bestimmten Sinne hinlänglich umfangreich ist. Es erweist sich, daß aus der Theorie der BANACH‐Algebren bekannte Beziehungen zwischen minimalen Idempotenten und minimalen Idealen ihr Analogon in solchen Algebren haben (Theorem 2.2) und ein Darstellungssatz (Theorem 2.6) gültig ist, der ebenfalls sein Vorbild in der Theorie der BANACHSCHEN und C*‐Algebren hat. In § 3 schließlich wird der elementare Operator z → bizci betrachtet, dessen Spezialfälle der bekannte und intensiv untersuchte Operator →bc: z bz– zc und insbesondere die innere Derivation δb: z bz – zb sind. Eine Aussage bei C. K. FONG und A. R. SOUROUR [5: Theorem 1], die dort eine Ausgangsschlüsselstellung einnimmt, wird auf lineare Algebren mit hinreichend vielen eindimensionalen Elementen über‐tragen und gestattet deshalb auch die Übertragung auf solche Algebren einer ganzen Reihe weiterer, dort für BANACH‐Algebren aufgezeigter Beziehungen algebraischen Charakters. Da sich mit den Fakten auch weitgehend deren Beweise übertragen lassen, werden wir uns dazu meistens auf wenige Kommentare beschränken.
On an Approximate Solution of Variational Inequalities
Authors: Kačur Jozef
Published: April 2007

By means of time discretization, we approximate evolution variational inequalities by the corresponding elliptic variational inequalities. Using ROTHE'S method (method of lines), an approximate solution is constructed by means of direct variational methods. Existence, uniqueness and regularity of solutions as well as convergence of the approximate solutions are proved.
Development and applications of surface‐activated chemical ionization
Authors: Cristoni Simone , Rubini Simone , Bernardi Luigi Rossi
Published: April 2007

This review regards the recently developed ionization source named surface‐activated chemical ionization (SACI) that employs an interaction with a surface placed at low voltage for the activation of the ionization of sample molecules to increase the sensitivity in the analysis of various compounds of biological and clinical interest. These results are due to the strong chemical noise decrease and the increase of ionization efficiency. This ionization source has been employed for the analysis of various compounds of different molecular mass and polarity (addicted and pharmaceutical drugs, aminoacids, steroids, peptides, and proteins). The SACI development theoretical mechanism, benefits, disadvantages, applications, and future developments are reported and discussed. © 2007 Wiley Periodicals, Inc., Mass Spec Rev 26:645–656, 2007
Structural Organization and Properties of Syndiotactic Polystyrene Gels
Authors: Daniel Christophe
Published: April 2007

In this manuscript, the structural organization of syndiotactic polystyrene (sPS) gels is reviewed with particular emphasis on the structure of molecular complexes (clathrates and intercalates) formed in sPS gels. Hereafter, results concerning macroscopic properties such as the rheological behaviour and the light transparency are reported and discussed on the basis of the gel molecular organization.
Thermo‐Responsive PNIPAAm Copolymers with Hydrophobic Spacers
Authors: Stoica Florentina , F. Miller Aline , Alexander Cameron , Saiani Alberto
Published: April 2007

We have synthesised and characterised three sets of acryloyl(amino‐acid)/NIPAAm co‐polymers. Three different co‐monomers were synthesised and copolymerized with N‐isopropylacrylamide (NIPAAm) by free radical polymerization in different molar ratios (12:1, 9:1, and 6:1). All series contain aliphatic spacers and are carboxylic terminated. The effect of co‐monomer nature and content on the glass transition and the LCST transition in solution has been investigated. The main factor affecting the glass transition and the LCST of the polymer was found to be the side chain length of the co‐monomer. The introduction of the co‐monomer resulted in an overall increase in the polymer hydrophobicity which led to a decrease of both the polymer glass transition and the LCST transition observed in solution.
Gelation of a Model Globular Protein
Authors: Yan Hui , Saiani Alberto , Miller Aline F.
Published: April 2007

Hen egg white lysozyme (HEWL) was exposed to various physical and chemical denaturing environments to encourage protein denaturation and consequent gelation. Its phase behavior was examined as a function of pH, temperature and also in the presence of the reductant dithiothreitol (DTT). Transparent viscoelastic gels form at low pH values while opaque gels form under alkaline conditions. No increase in viscosity was observed for systems in pure water unless 20 mM of DTT was added, which is known to break the disulfide bridges present in HEWL. The microstructure of the gel was studied using transmission electron microscopy (TEM) and environmental scanning electron microscopy (ESEM). Gels formed at low pH contain fibrils ∼10 nm in diameter with various lengths while at high pH the gels are dominated by particulate aggregates. Thinner fibrils that are 4–6 nm in diameter are observed in the gels formed in the presence of DTT. In this case the distinct feature of the gels is they are thermoreversible and can be melted and reformed easily by varying the temperature.
Schwingfestigkeit von Schraube‐Mutter‐Verbindungen
Authors: Alt A. , Mertens H. , Arz U. , Blessing L. , Berger C.
Published: April 2007

Im vorliegenden Beitrag werden Erkenntnisse aus umfangreichen Versuchen zur Überlagerung von Zug‐ und Biegebeanspruchungen, des torsionsbehafteten sowie überelastischen Vorspannens und der Charge auf die Schwingfestigkeit von Schraube‐Mutter‐Verbindungen zusammengefasst, die in der VDI Richtlinie 2230 bislang nicht enthalten sind. Zur Durchführung der Schwingversuche wurden völlig neuartige Resonanzprüfvorrichtungen entwickelt, die einen kostengünstigeren Betrieb als die bislang eingesetzten Hochfrequenz‐ und Hydropulser ermöglichen und die sich für Nenndurchmesser bis M100 und Prüffrequenzen bis 1000 Hz eignen. Der Geltungsbereich der Dauerfestigkeit nach VDI 2230 wird aufgrund der Ergebnisse spezifiziert. Der festgestellte überraschend hohe Chargeneinfluss gibt Anlass, den Fertigungsprozess von Schrauben zur Begrenzung dieses Einflusses zu präzisieren.
Lebensdauerabschätzung an Kunststoffrohren mittels Zeitstand‐Innendruckversuch
Authors: Berger C. , Bockenheimer A.
Published: April 2007

Die Lebensdauervorhersage an Kunststoffrohren basiert nach dem aktuellen Stand des technischen Regelwerkes hauptsächlich auf dem Zeitstand‐Innendruckversuch. In diesem Versuch werden die Rohre bei definiertem Innendruck und erhöhten Temperaturen akzeleriert geprüft, und aufgrund des geltenden Arrheniusgesetzes erfolgt daraufhin eine Lebensdauerextrapolation der Messwerte.
Methoden zur Bewertung rissartiger Fehler betriebsbeanspruchter Kraftwerksbauteile im Langzeitbereich
Authors: Ewald J. , Müller F. , Mao T. , Scholz A. , Machalowska‐Tracz M. , Klenk A.
Published: April 2007

Zur Auslegung und Überwachung langzeitig eingesetzter Hochtemperaturbauteile des Kraftwerkbaus werden Unterlagen über das Werkstoffverhalten an rissartigen Fehlern und konstruktiv nicht vermeidbaren Kerben benötigt. An solchen Stellen können Kriech‐ und/oder Kriechermüdungsrisse durch statische und/oder zyklische Hochtemperaturbeanspruchung eingeleitet werden und anschließend wachsen. Risseinleitung und Rissfortschritt bedürfen einer experimentell abgesicherten, quantitativen Beschreibung.

In den letzten 25 Jahren wurden dazu für eine große Anzahl von Hochtemperaturwerkstoffen entsprechende Langzeitdaten an Bruchmechanikproben ermittelt und anhand unterschiedlicher Konzepte die Übertragbarkeit auf das Rissverhalten in Hochtemperaturbauteilen erarbeitet und abgesichert. Als wichtige Konzepte seien hier das Zwei‐Kriterien‐Diagramm zur Bewertung der Kriechrisseinleitung und der Parameter C* zur Bewertung des Kriechrissfortschritts genannt.

Damit die Daten und Konzepte benutzerfreundlich zur Verfügung gestellt werden können, wurden diese in das Programmsystem „HT‐RISS”︁ zusammengeführt. Mit dem erarbeiteten Programmsystem lassen sich Berechnungen zum Hochtemperaturrissverhalten durchführen, die eine wesentliche Sicherheitsgrundlage für Auslegung, Betrieb und Überwachung von Hochtemperaturbauteilen darstellen.
Vibration sensitivity of human muscle spindles and golgi tendon organs
Authors: Fallon James B. , Macefield Vaughan G.
Published: April 2007

The responses of the various muscle receptors to vibration are more complicated than a naïve categorization into stretch (muscle spindle primary ending), length (muscle spindle secondary endings), and tension (Golgi tendon organs) receptors. To emphasize the similarity of responses to small length changes, we recorded from 58 individual muscle afferents subserving receptors in the ankle or toe dorsiflexors of awake human subjects (32 primary endings, 20 secondary endings, and six Golgi tendon organs). Transverse sinusoidal vibration was applied to the distal tendon of the receptor‐bearing muscle, while subjects either remained completely relaxed or maintained a weak isometric contraction of the appropriate muscle. In relaxed muscle, few units responded in a 1:1 manner to vibration, and there was no evidence of a preferred frequency of activation. In active muscle the response profiles of all three receptor types overlapped, with no significant difference in threshold between receptor types. These results emphasize that when intramuscular tension increases during a voluntary contraction, Golgi tendon organs and muscle spindle secondary endings, not just muscle spindle primary endings, can effectively encode small imposed length changes. Muscle Nerve, 2007
A critical review of forms of corporate community involvement: from philanthropy to partnerships
Authors: Seitanidi Maria May , Ryan Annmarie
Published: April 2007

The paper offers a critical review of the forms of corporate community involvement (CCI) including: corporate philanthropy, benefaction, patronage, sponsorship and cause related marketing (CRM) and partnership. It discusses the differences/similarities and compares the limitations of the transactional forms of interaction with the latest form of partnership.

The paper suggests that the form of partnership represents a shift towards a non‐linear business model of CCI, that is moving away from an outcome towards a process orientation. Three factors are identified conditioning the successful implementation and sustainability of partnerships which are linked with the previous limitations of transactional approaches of interaction. Finally, the paper puts forward three propositions in order for partnerships to: (1) contribute to the increase of institutional trust among organisations and across sectors; (2) assist in balancing the dynamics across the sectors and (3) appreciate the process of interaction as a source of benefits.

Copyright © 2007 John Wiley & Sons, Ltd.
Global gene expression profiling of PAX‐FKHR fusion‐positive alveolar and PAX‐FKHR fusion‐negative embryonal rhabdomyosarcomas
Authors: Laé M , Ahn EH , Mercado GE , Chuai S , Edgar M , Pawel BR , Olshen A , Barr FG , Ladanyi M
Published: April 2007

Paediatric rhabdomyosarcomas (RMS) are classified into two major subtypes based on histological appearance, embryonal (ERMS) and alveolar (ARMS), but this clinically critical distinction is often difficult on morphological grounds alone. ARMS, the more aggressive subtype, is associated in most cases with unique recurrent translocations fusing the PAX3 or PAX7 transcription factor genes to FKHR. In contrast, ERMS lacks unique genetic alterations. To identify novel diagnostic markers and potential therapeutic targets, we analysed the global gene expression profiles of these two RMS subtypes in 23 ARMS (16 PAX3‐FKHR, 7 PAX7‐FKHR) and 15 ERMS (all PAX‐FKHR‐negative) using Affymetrix HG‐U133A oligonucleotide arrays. A statistically stringent supervised comparison of the ARMS and ERMS expression profiles revealed 121 genes that were significantly differentially expressed, of which 112 were higher in ARMS, including genes of interest as potential diagnostic markers or therapeutic targets, such as CNR1, PIPOX (sarcosine oxidase), and TFAPβ. Interestingly, many known or putative downstream targets of PAX3‐FKHR were highly overexpressed in ARMS relative to ERMS, including CNR1, DCX, ABAT, ASS, JAKMIP2, DKFZp762M127, and NRCAM. We validated the highly differential expression of five genes, including CNR1, DKFZp762M127, DCX, PIPOX, and FOXF1 in ARMS relative to ERMS by quantitative RT‐PCR on an independent set of samples. Finally, we developed a ten‐gene microarray‐based predictor that distinguished ARMS from ERMS with approximately 95% accuracy both in our data by cross‐validation and in an independent validation using a published dataset of 26 samples. The gene expression signature of ARMS provides a source of potential diagnostic markers, therapeutic targets, and PAX‐FKHR downstream genes, and can be used to reliably distinguish these sarcomas from ERMS. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Analysis of potential receptor tyrosine kinase targets in intimal and mural sarcomas
Authors: Tamborini E , Casieri P , Miselli F , Orsenigo M , Negri T , Piacenza C , Stacchiotti S , Gronchi A , Pastorino U , Pierotti MA , Pilotti S
Published: April 2007

Primary sarcomas of the great vessels are very rare neoplasms and only a few cases have been reported. They are divided into the two broad categories of intimal or luminal and mural sarcomas. We analysed eight advanced high‐grade sarcomas originating from major vessels (seven intimal and one mural sarcoma) by means of immunohistochemistry and FISH analysis for PDGFRA, PDGFRB, EGFR and KIT receptor tyrosine kinases (RTKs), together with immunoprecipitation/western blotting, sequencing of the corresponding genes, and the search for cognate ligands. The intimal sarcomas showed a wide spectrum of morphologies and immunophenotypes, whereas the mural sarcoma had common leiomyosarcomatous features. Regardless of their category, all of the cases had a PDGFRA‐deregulated cytogenetic profile mainly consisting of an amplification cluster; five were also polysomic for PDGFRB, whereas three showed disomy. Six cases had a deregulated EGFR gene, and c‐Kit gene status was similar to that of PDGFRA. In one case, biochemical analysis revealed the presence of activated and highly expressed PDGFRA, PDGFRB and EGFR, whereas KIT was expressed at reference level. Sequencing of the corresponding genes revealed no activating mutations in any of the analysed receptors. The cognate ligands were detected in all cases. In predictive terms, the evidence of gene amplification/high polysomy of several RTKs, together with PDGFRA, PDGFRB and EGFR expression and phosphorylation, suggests that these tumours may be sensitive to RTK‐inhibiting treatments. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
An experimental study of uniaxial fatigue behavior of an epoxy resin by a new noncontact real‐time strain measurement and control system
Authors: Tao Gang , Xia Zihui
Published: April 2007

Uniaxial fatigue behavior of an epoxy resin was investigated with a recently established non‐contact real‐time strain measurement and control system. A relation of strain amplitude vs. fatigue life for fully‐reversed strain‐range‐controlled uniaxial fatigue tests was obtained. Quantitative analyses of evolutions of various mechanical properties (including stress range, elastic modulus, nonlinear stress‐strain relation, dissipated strain energy density, etc.) during entire fatigue life period were carried out based on recorded stress‐strain data. From the evolution of the stress‐strain hysteresis loops, a gradual degradation of modulus and a decrease of nonlinear effect in stress‐strain response were observed. It was also found that these two phenomena were independent of the loading control mode (stress‐control or strain‐range‐control) and the mean stress/strain values in the cyclic loading. Fractographic analysis was also performed and the mechanism of crack initiation and propagation of the epoxy material under cyclic loading was investigated. POLYM. ENG. SCI., 47:780–788, 2007. © 2007 Society of Plastics Engineers
Embossing of high‐aspect‐ratio‐microstructures using sacrificial templates and fast surface heating
Authors: Lu Chunmeng , Cheng Mark Ming‐Cheng , Benatar Avraham , Lee L. James
Published: April 2007

A new embossing method based on sacrificial templates and fast surface heating was developed, in which the de‐embossing step was avoided to prevent deformation or damage of polymer microstructures. The microstructures of interest have a high feature density, high aspect ratio, and/or undercuts. Soft lithography was used to prepare a water‐soluble mold, using polyvinylpyrrolidone (PVP) in the hot embossing process. Arrays of microchannels and microgrids with an aspect ratio greater than five were replicated on poly(DL‐lactide‐co‐glycolide) (PLGA). In conjunction with localized surface heating of the polymer surface by a laser/IR system, this technique was able to micromold high temperature polymers such as poly(methyl methacrylate) (PMMA) with high aspect ratios. POLYM. ENG. SCI., 47:830–840, 2007. © 2007 Society of Plastics Engineers
Theoretical and experimental analysis of the die drool phenomenon for metallocene LLDPE
Authors: Chaloupková Kateřina , Zatloukal Martin
Published: April 2007

The die drool phenomenon, occurring as a result of the viscoelastic behavior of polymer melts during the flow, was experimentally investigated for metallocene‐based LLDPE on a specially designed annular extrusion die with the capability to control the stress state at the end of the die by the help of a specific type of cooling system. With the aim of understanding the die drool phenomenon in more detail, the flow at the end of the die was analyzed theoretically by the finite element method employing a modified White–Metzner model as the constitutive equation. It has been revealed that negative pressure occurs at the die lip area, which seems to be an important factor driving the onset of the die drool phenomenon. POLYM. ENG. SCI., 47:871–881, 2007. © 2007 Society of Plastics Engineers
Twin‐screw extrusion of polypropylene‐clay nanocomposites: Influence of masterbatch processing, screw rotation mode, and sequence
Authors: Treece Mark A. , Zhang Wei , Moffitt Ronald D. , Oberhauser James P.
Published: April 2007

This work seeks to optimize the twin‐screw compounding of polymer‐clay nanocomposites (PCNs). Proportional amounts (3:1) of maleic anhydride functionalized polypropylene compatibilizer (PP‐g‐MA) and organically modified montmorillonite clay at clay loadings of 1, 3, and 5 wt% were melt‐blended with a polypropylene (PP) homopolymer using a Leistritz Micro 27 twin‐screw extruder. Three melt‐blending approaches were pursued: (1) a masterbatch of PP‐g‐MA and organoclay were blended in one pass followed by dilution with the PP resin in a second pass; (2) all three components were processed in a single pass; and (3) uncompatibilized PP and organoclay were processed twice. Both corotation and counterrotation operation were utilized to investigate the effect of screw rotation mode and sequence on organoclay exfoliation and dispersion. X‐ray diffraction was employed to characterize basal spacing; however, since rheology is known to be highly sensitive to mesoscale organoclay structure, it is an ideal tool to examine the relationship between the various processing methods and exfoliation and dispersion. A holistic analysis of rheological data demonstrates the efficacy of the masterbatch approach, particularly when compatibilizer and organoclay are blended in counterrotating mode followed by dilution with matrix polymer in corotating mode. POLYM. ENG. SCI., 47:898–911, 2007. © 2007 Society of Plastics Engineers
Mechanical, thermal, and morphological characteristics of compatibilized and dynamically vulcanized polyoxymethylene/ethylene propylene diene terpolymer blends
Authors: Uthaman R. Nalini , Pandurangan A. , Majeed S.S.M. Abdul
Published: April 2007

Dynamically vulcanized blends of polyoxymethylene (POM) and ethylene propylene diene terpolymer (EPDM) with and without compatibilizer were prepared by melt mixing in a twin screw extruder. Maleic anhydride (MAH) grafted EPDM (EPDM‐g‐MAH) has been used as a compatibilizer. Dicumyl peroxide was used for vulcanizing the elastomer phase in the blends. Mechanical, dynamical mechanical, thermal, and morphological properties of the blend systems have been investigated as a function of blend composition and compatibilizer content. The impact strength of both dynamically vulcanized blends and compatibilized/dynamically vulcanized blends increases with increase in elastomer content with decrease in tensile strength. Dynamic mechanical analysis shows decrease in tanδvalues as the elastomer and compatibilizer content increased. Thermograms obtained from differential scanning calorimetric studies reveal that compatibilized blends have lowerTmvalues compared to dynamically vulcanized blends, which confirms strong interaction between the plastic and elastomer phase. Scanning electron microscopic observations on impact fractured surface indicate reduction in particle size of elastomer phase and its high level of dispersion in the POM matrix. In the case of compatibilized blends high degree of interaction between the component polymers has been observed. POLYM. ENG. SCI., 47:934–942, 2007. © 2007 Society of Plastics Engineers
Assessing the effect of visual isolation on the population density of Atlantic salmon (Salmo salar) using GIS
Authors: Dolinsek Ivan J. , Biron Pascale M. , Grant James W. A.
Published: April 2007

Few studies investigate the behavioural response of organisms to stream enhancement schemes. One behavioural process that is rarely examined in enhancement studies is the visual isolation created by adding boulders on the river bed. The objective of this research is to use a Geographic Information Systems (GIS) viewshed analysis to determine if the increase in density of Atlantic salmon observed in boulder‐added zones is related to visual isolation or, alternatively, the presence of a velocity refuge. Eight study sites were established on Catamaran Brook and Little Southwest Miramichi River (New Brunswick, Canada). Each reach was divided into three quadrats of 3 m × 2 m. In one of the quadrats, 36 boulders (D50 = 0.20 m) were added to increase visual isolation. Boulders were removed from another adjacent quadrat whereas a third quadrat was left in a natural state. A detailed Digital Elevation Model (DEM) was created for all the sites with a total station. Atlantic salmon were observed by snorkelling on several occasions during two summers. Their position was recorded with the total station and the snout and average velocity was measured. A GIS viewshed analysis was performed to determine the visible area for each fish and to verify whether the surrounding fish were visible or not. Results suggest that the primary mechanism responsible for the observed increase in Atlantic salmon population density in the experimental quadrats is a reduction in the field of view of individuals, through an increase in habitat heterogeneity, which is consistent with the visual isolation hypothesis. There was also no change in the snout velocity of salmon among the three treatments, suggesting that the increase in density is not consistent with the velocity‐refuge hypothesis. Copyright © 2007 John Wiley & Sons, Ltd.
Salmonid observations at a Klamath River thermal refuge under various hydrological and meteorological conditions
Authors: Sutton Ronald J. , Deas Michael L. , Tanaka Stacy K. , Soto Toz , Corum R. Alex
Published: April 2007

The Beaver Creek confluence with the main‐stem Klamath River was studied to assess salmonid use in a thermal mixing zone under various summer hydrological and meteorological conditions. Main‐stem flow releases from Iron Gate Dam ranged from 17 cms (615 cfs) to 37 cms (1320 cfs) during the study period and main‐stem water temperatures ranged from 19.5 to 26°C. A grid was constructed to define the thermal refuge as a system of cells. Temperatures were monitored using remote temperature loggers and fish counts were conducted using daytime snorkelling. Most juvenile salmonids were observed moving into the refuge when main‐stem temperatures exceeded 22–23°C. Salmonids in the thermal refuge did not necessarily seek the coolest water, but were generally located in habitats commensurate with species‐specific behavioural needs within their thermal tolerance range. Such ranges largely occurred within refuge areas. Variable meteorological conditions confounded observable biological thermal benefit to fish resulting from higher or lower main‐stem flows. Thermal regime dynamics indicated that under the hydrological and meteorological conditions observed, higher flows from Iron Gate Dam showed some ability to change the structure of the refuge area. It appeared that without the thermal refuge, main‐stem flows alone could not sustain the salmonid population because high water temperatures usually exceeded their published thermal tolerance limits. Copyright © 2007 John Wiley & Sons, Ltd.
Cationisation of oligomeric alkylethoxylate surfactants in ToF‐SIMS analysis
Authors: Perkins M. C. , Briggs D. , Rutten F. J. M. , Roberts C. J. , Davies M. C.
Published: April 2007

Variable cationisation of the alkylethoxylate surfactant Synperonic A7™ has been observed during a ToF‐SIMS study of its interaction with a leaf surface, either by itself or as a component in a simple herbicide formulation. Depending on the conditions, cationisation predominantly by K+, Na+ and H+ was found. By deliberate surfactant solution doping with alkali bromides, the cationisation channel could be manipulated. Comparison of the apparent molecular weight dependence, derived from the ToF‐SIMS spectra, with that measured by HPLC‐MS, showed a further dependence on the cationising species, with Na+ giving the best match. An understanding of these effects is critical to the correct interpretation of the spectra from this surfactant. Copyright © 2007 John Wiley & Sons, Ltd.
Seil‐ und Membrankonstruktionen – Kinematik als Gemeinsamkeit
Authors: Wagner Rosemarie
Published: April 2007

Seile und Membranen als unbeschichtete oder beschichtete Gewebe und Folien werden nur zugbeansprucht, können nicht ausknicken, sind biegeweich und führen mit hochfesten Werkstoffen zu leichten Konstruktionen. Die Besonderheiten von Seilen und Membranen sind ihre große Kinematik, die durch den Seilaufbau und die Webtextur von Bauteilen besteht, durch die in den Tragwerken große Verformungen unter Last auftreten. Tragwerke mit zugbeanspruchten Bauteilen können als vorgespannte Konstruktion Lasten abtragen, obwohl sie im Aufbau kinematisch sind. Der Umgang mit Bauteilen und Tragwerken, denen eine Kinematik zugrunde liegt, deren Ursache dehnungslose Verformungen oder Starrkörperverschiebungen sind, ist in der Bautechnik ungewöhnlich und erfordert im Vergleich zu üblichen Konstruktionen ein anderes Verständnis im Umgang mit zugbeanspruchten Bauteilen und deren Tragwerke. Die Kinematik lässt sich in den Werkstoffen, in den Bauteilen und in den Tragwerken finden und ist in den Ursachen und Auswirkungen zu verstehen, um dauerhafte Tragwerke zu gewährleisten.
Talbrücke Elben – Eine Stahlverbundbrücke mit einteiligem Querschnitt
Authors: Hilgendorff Klaus‐Dieter , Neumann Winfried , Reitz Dieter , Schmitz Christoph
Published: April 2007

Nördlich von Siegen wurde in den letzten Jahren ein weiterer Abschnitt der Autobahn A 4 und der B 54n, Hüttentalstraße (HTS), fertiggestellt. Im Rahmen der Baumaßnahme wurde im Zuge der A 4 die Talbrücke Elben als 432 m lange Stahlverbundbrücke mit einem einteiligen Querschnitt errichtet. Da in den letzten Jahren etwa 10 solcher Bauwerke entstanden sind und weitere Brücken mit diesem Querschnitt geplant sind, soll in diesem Aufsatz über die bisherigen Erfahrungen im Allgemeinen und über die Talbrücke Elben im Speziellen berichtet werden. Darüber hinaus erfolgt ein Ausblick auf den weiteren möglichen Anwendungsbereich dieses Brückensystems.
Information Processing in the Context of Genetic Risk: Implications for Genetic‐Risk Communication
Authors: Etchegary Holly , Perrier Colin
Published: April 2007

Communicating genetic‐risk information is fraught with difficulties, and there are no universally accepted guidelines for clinical practice. In this paper, we suggest that information‐processing models may offer some guidance for the communication of genetic risk. The paper reviews selected literature from health and social psychology, including defensive reactions to threatening health information, the Extended Parallel Process Model (EPPM) and Self Affirmation Theory. Ultimately, it presents the Heuristic‐Systematic Model (HSM) of information processing as a useful perspective from which to view genetic‐risk communication. Through our review of this literature, we identify some of the variables found to influence the systematic or heuristic processing of risk information and note their relevance to genetic counseling contexts. We suggest that systematic information processing is conducive to informed decision‐making, as well as improved understanding of risk information. Clinical practice implications derived from our review of these literatures are noted.
Replacement of Dietary Fish Oils by Alpha‐Linolenic Acid‐Rich Oils Lowers Omega 3 Content in Tilapia Flesh
Authors: Karapanagiotidis Ioannis T. , Bell Michael V. , Little David C. , Yakupitiyage Amararatne
Published: April 2007

A 20‐week feeding trial was conducted to determine whether increasing linolenic acid (18:3n‐3) in vegetable oil (VO) based diets would lead to increased tissue deposition of 22:6n‐3 in Nile tilapia (Oreochromis niloticus). Five isonitrogenous and isoenergetic diets were supplemented with 3% of either linseed oil (LO), a mixture of linseed oil with refined palm olein oil (PO) (LO–PO 2:1) and a mixture of refined palm olein oil with linseed oil (PO–LO 3:2) or with fish oil (FO) or corn oil (CO) as controls. The PO–LO, LO–PO and LO diets supplied a similar amount of 18:2n‐6 (0.5% of diet by dry weight) and 0.5, 0.7 and 1.1% of 18:3n‐3, respectively. Increased dietary 18:3n‐3 caused commensurate increases in longer‐chain n‐3 PUFA and decreases in longer‐chain n‐6 PUFA in the muscle lipids of tilapia. However, the biosynthetic activities of fish fed the LO‐based diets were not sufficient to raise the tissue concentrations of 20:5n‐3, 22:5n‐3 and 22:6n‐3 to those of fish fed FO. The study suggests that tilapia (O. niloticus) has a limited capacity to synthesise 20:5n‐3 and 22:6n‐3 from dietary 18:3n‐3. The replacement of FO in the diet of farmed tilapia with vegetable oils could therefore lower tissue concentrations of 20:5n‐3 and 22:6n‐3, and consequently produce an aquaculture product of lower lipid nutritional value for the consumer.
Self‐reported reactive and regulative temperament in early adolescence: Relations to internalizing and externalizing problem behavior and “Big Three” personality factors
Authors: Muris Peter , Meesters Cor , Blijlevens Pim
Published: April 2007

The present study examined the relations between self‐reported reactive and regulative temperament factors and psychopathological symptoms and personality traits in a group of non‐clinical youths aged 9–13 years (N=208). Results showed that the reactive temperament factor of negative affectivity was positively associated with internalizing and externalizing symptoms, whereas the regulative temperament factor of effortful control was negatively related to such symptoms. Further analyses provided some support for the notion that in particular the combination of high negative affectivity and low effortful control was associated with high symptom levels. Results also revealed specific relations between lower‐order temperament traits and internalizing and externalizing symptoms. That is, fear and (low) attention control appeared to be more clearly associated with internalizing symptoms, whereas anger/frustration and (low) activation and inhibitory control were more convincingly linked to externalizing symptoms. Finally, relations with the “Big Three” personality traits were as anticipated, with high positive correlations between negative affectivity and extraversion/surgency and their Eysenckian counterparts of neuroticism and extraversion, respectively.
Influence of cardiac resynchronisation therapy on different types of sleep disordered breathing
Authors: Oldenburg Olaf , Faber Lothar , Vogt Jürgen , Dorszewski Anja , Szabados Florian , Horstkotte Dieter , Lamp Barbara
Published: April 2007

Aims

This study investigates the influence of cardiac resynchronisation therapy (CRT) on sleep disordered breathing (SDB) in patients with severe heart failure (HF).

Methods and results

Seventy‐seven patients with HF (19 females; 62.6±10 years) eligible for CRT were screened for presence, type, and severity of SDB before and after CRT initiation (5.3±3 months) using cardiorespiratory polygraphy. NYHA class, frequency of nycturia, cardiopulmonary exercise, 6‐minute walking test results, and echocardiography parameters were obtained at baseline and follow‐up.

Central sleep apnoea (CSA) was documented in 36 (47%), obstructive sleep apnoea (OSA) in 26 (34%), and no SDB in 15 (19%) patients. CRT improved clinical and haemodynamic parameters. SDB parameters improved in CSA patients only (apnoea hypopnoea index: 31.2±15.5 to 17.3±13.7/h, p<0.001; SaO2min: 81.8±6.6 to 84.8±3.3%, p=0.02, desaturation: 6.5±2.3 to 5.5±0.8%, p=0.004). Daytime capillary pCO2 was significantly lower in CSA patients compared to those without SDB with a trend towards increase with CRT (35.5±4.2 to 37.9±5.7 mm Hg, ns). After classifying short term clinical and haemodynamic CRT effects, improved SDB parameters in CSA occurred in responders only.

Conclusions

In patients with severe HF eligible for CRT, CSA is common and can be influenced by CRT, this improvement depends on good clinical and haemodynamic response to CRT.
Reducing maternal mortality due to elective abortion: Potential impact of misoprostol in low‐resource settings
Authors: Harper C.C. , Blanchard K. , Grossman D. , Henderson J.T. , Darney P.D.
Published: April 2007

Over 99% of deaths due to abortion occur in developing countries. Maternal deaths due to abortion are preventable. Increasing the use of misoprostol for elective abortion could have a notable impact on maternal mortality due to abortion. As a test of this hypothesis, this study estimated the reduction in maternal deaths due to abortion in Africa, Asia and Latin America. The estimates were adjusted to changes in assumptions, yielding different possible scenarios of low and high estimates. This simple modeling exercise demonstrated that increased use of misoprostol, an option for pregnancy termination already available to many women in developing countries, could significantly reduce mortality due to abortion. Empirical testing of the hypothesis with data collected from developing countries could help to inform and improve the use of misoprostol in those settings.
The Latent Phase of Labor: Diagnosis and Management
Authors: Greulich Betsy , Tarrant Beth
Published: April 2007

The latent phase of labor is complex and not completely understood by modern science. Studies often ignore evaluation of this phase of labor because determination of onset is subjective. In this article, the definition and time parameters of latent phase labor are discussed, and generalized distinctions between prelabor and labor are evaluated. Outpatient relief measures for latent phase as well as inpatient medical interventions for prolonged latent phase of labor are reviewed. Recommendations for policy development are included along with a discussion about the need to consider the significance of time limits. For optimal outcomes, clinicians are encouraged to individualize a management plan that is made in collaboration with the laboring woman.
Intrauterine Resuscitation During Labor: Review of Current Methods and Supportive Evidence
Authors: Simpson Kathleen Rice
Published: April 2007

When the fetal heart rate pattern is suggestive of fetal compromise during labor, various methods to promote fetal well‐being are traditionally initiated. They include maternal repositioning, reduction of uterine activity, an intravenous fluid bolus, oxygen administration, correction of maternal hypotension, amnioinfusion, and alteration of second‐stage labor pushing efforts. Although these intrauterine resuscitation techniques are commonly used, and in some cases considered standard care, supportive data could be more robust. Nevertheless, there is enough evidence to suggest they are beneficial to the fetus and there is minimal risk of harm when used with clinical common sense. Until more data are available, it seems reasonable to err on the side of fetal safety by using these techniques when appropriate, based on the specific fetal heart rate pattern.
Midwifery Management of Prelabor Rupture of Membranes at Term
Authors: Marowitz Amy , Jordan Robin
Published: April 2007

Spontaneous rupture of membranes before the onset of labor at term is commonly referred to as PROM (either premature or preterm rupture of membranes) and occurs in about 8% of term pregnancies. PROM is associated with an increased risk of infection. Many controversies exist regarding the optimal management of PROM, including the choice of induction or expectant management, use of digital vaginal exams, and routine administration of antibiotics. This article reviews the literature on PROM and illustrates some of the management issues encountered by presenting approaches used in three midwifery services.
Breastfeeding Initiation and Birth Setting Practices: A Review of the Literature
Authors: Forster Della A. , McLachlan Helen L.
Published: April 2007

A number of practices during the intrapartum and very early postnatal period may affect breastfeeding initiation. All women should be encouraged to breastfeed soon after birth, with extra attention paid to the identification and offer of extra support for those women at higher risk of not successfully initiating and continuing breastfeeding. Factors that affect breastfeeding initiation include: implementation of the Baby‐Friendly Hospital Initiative Ten Steps to Successful Breastfeeding at a service level; avoidance of the use of intramuscular narcotic analgesia, particularly near the end of the first stage of labour; not separating mothers and babies after birth for routine procedures; and placing healthy newborns on their mothers' chest/abdomen (skin‐to‐skin) routinely. Single strategies are unlikely to increase breastfeeding initiation as stand‐alone measures.
Perinatal Care of Women Maintained on Methadone
Authors: Goff Meredith , O'Connor Meghan
Published: April 2007

A 2005 national survey found that nearly 4% of pregnant women between the ages of 15 and 44 reported illicit drug use in the previous month. Among pregnant women admitted to substance abuse programs, 15% identified heroin as the primary substance used. Methadone is a recommended treatment for pregnant women wishing to discontinue their use of heroin. Providers of peripartum care may be unaware of the specific needs of this population, which are illustrated in this case discussion.
Born Too Soon: The Continuing Challenge of Preterm Labor and Birth in the United States
Authors: Reedy Nancy Jo
Published: April 2007

Prematurity is the single greatest cause of morbidity and mortality in obstetrics. Families, health care services, and education systems experience the impact of prematurity for the lifetime of the preterm‐born child. Health care providers have tried to lower the preterm birth rate with prevention both before and during pregnancy and intervention for symptomatic women. The inability of the health care system to significantly decrease the incidence of preterm birth continues to be a challenge. To further complicate the situation, new data shows that infants born between 34 and 37 weeks' gestation who were thought to have minimal long‐term effects of preterm birth may be more at risk than previously appreciated. This article reviews evidence‐based risk identification, prevention, and management of women experiencing preterm labor and birth.
A Review of Factors Associated With Dystocia and Cesarean Section in Nulliparous Women
Authors: Lowe Nancy K.
Published: April 2007

The primary indication for cesarean section in nulliparous women continues to be clinical diagnoses that fall under the rubric of dystocia. These diagnoses account for approximately two‐thirds of all cesareans experienced by otherwise healthy nulliparous women. Contemporary research evidence suggests that this clinical phenomenon is complex and multifactorial. This review explores factors associated with the phenomenon of dystocia in the context of a conceptual model that considers women's physical and psychological characteristics, fetal factors, intrapartum care and interventions, assessments and clinical decision‐making of health care providers, the sociopolitical environment, and the social and physical environment of childbirth. Clinical recommendations include emphasis on the maintenance of normal weight and weight gain during pregnancy, delaying the admission of nulliparous women to the hospital until active labor is established, avoiding elective induction for nulliparous women, keeping women well‐hydrated and well‐fed during labor, providing high‐quality supportive care during labor, staying the course with effective treatment when dystocia is encountered, and a renewed emphasis on the psychobehavioral preparation of nulliparous women for the realities of labor.
Market switching in shipping — A real option model applied to the valuation of combination carriers
Authors: Sødal Sigbjørn , Koekebakker Steen , Aadland Roar
Published: April 2007

This paper derives a real options model of flexibility and applies it to shipping, valuing the option to switch between the dry bulk market and wet bulk market for a combination carrier, a ship type that is capable of operating in both markets but that has fallen out of favor due to high price tags. The model is a mean‐reverting (Ornstein–Uhlenbeck) version of a standard entry–exit model with stochastic prices. A closed form solution for the value of flexibility is derived, expressed in terms of Kummer functions. The estimated value of flexibility is related to historical price differentials between combination carriers and oil tankers of comparable size. Based on numerical experiments it is concluded that new combination carriers may enter the market in the near future.
Characterization of Fiore Sardo cheese manufactured with the addition of autochthonous cultures
Authors: Pisano M Barbara , Elisabetta Fadda M , Deplano Maura , Corda Arianna , Casula Maddalena , Cosentino Sofia
Published: April 2007

This work evaluated the effect of adjunct autochthonous cultures on the chemical, microbiological and sensory characteristics of Fiore Sardo cheese during ripening. A total of twelve batches of cheeses were manufactured according to the technical Disciplinary of Fiore Sardo cheese, with and without different combinations of autochthonous strains isolated from the native microflora of artisanal Fiore Sardo. There were no significant differences in the cheese compositional parameters between experimental and control cheeses, but the addition of cultures led to a statistically significant decrease in pH values in experimental cheeses. The evolution of total mesophilic bacteria, total coliforms and lactic acid bacteria were significantly influenced by the addition of autochthonous cultures in most of the experimental cheeses. As for sensory characteristics, all the experimental cheeses reported significantly higher scores especially for shape, texture, interior openings, taste and aftertaste. This study demonstrated the beneficial effect of the addition of selected autochthonous cultures in accelerating the disappearance of undesirable flora and improving the typical sensory characteristics of the cheese, and confirmed the importance of ewes' milk as a source of technologically interesting strains that could be used to ensure a higher quality of artisanal cheese productions.