bluuebunny/crossref_metadata_2025 huggingface dataset:
Meeting the research agenda in Australian radiation therapy: the current picture
Authors: Wright C.A. , Hilder B. , Schneider-Kolsky M.E.
Published: June 2009

In recent years the role of the radiation therapist (RT) has increasingly evolved. In Australia, one of the major developments has been the transition from practice which was rarely based on scientific evidence, to the profession today which engages in and incorporates research into everyday practice. The aim of this article is to provide an insight into the current status of Australian radiation therapy research. In order to present a national overview, a survey relating to research activity was e-mailed to all (48) clinical centres in Australia. Thirty-six out of the 48 centres responded, representing 13 private and 23 public centres. The results demonstrated that a research culture is beginning to be established and that there are challenges associated with implementing research. The role of universities in facilitating the development of research skills was considered important with an increasing number of practitioners undertaking higher research degrees. Overall, research activity in the Australian radiation therapy community is becoming more prevalent. If the profession is to continue to strengthen its research profile the professional body and universities need to continue providing academic and funding support. Greater focus on multidisciplinary collaboration is needed with direct involvement of RTs in multi-centre studies.
Metabolic factors affecting the inflammatory response of periparturient dairy cows
Authors: Sordillo Lorraine M. , Contreras G. A. , Aitken Stacey L.
Published: June 2009

Dairy cattle are susceptible to increased incidence and severity of disease during the periparturient period. Increased health disorders have been associated with alterations in bovine immune mechanisms. Many different aspects of the bovine immune system change during the periparturient period, but uncontrolled inflammation is a dominant factor in several economically important disorders such as metritis and mastitis. In human medicine, the metabolic syndrome is known to trigger several key events that can initiate and promote uncontrolled systemic inflammation. Altered lipid metabolism, increased circulating concentrations of non-esterified fatty acids and oxidative stress are significant contributing factors to systemic inflammation and the development of inflammatory-based diseases in humans. Dairy cows undergo similar metabolic adaptations during the onset of lactation, and it was postulated that some of these physiological events may negatively impact the magnitude and duration of inflammation. This review will discuss how certain types of fatty acids may promote uncontrolled inflammation either directly or through metabolism into potent lipid mediators. The relationship of increased lipid metabolism and oxidative stress to inflammatory dysfunction will be reviewed as well. Understanding more about the underlying cause of periparturient health disorders may facilitate the design of nutritional regimens that will meet the energy requirements of cows during early lactation and reduce the susceptibility to disease as a function of compromised inflammatory responses.
Bovine herpes virus infections in cattle
Authors: Nandi S. , Kumar Manoj , Manohar M. , Chauhan R. S.
Published: June 2009

Bovine herpes virus 1 (BHV-1) is primarily associated with clinical syndromes such as rhinotracheitis, pustular vulvovaginitis and balanoposthitis, abortion, infertility, conjunctivitis and encephalitis in bovine species. The main sources of infection are the nasal exudates and the respiratory droplets, genital secretions, semen, fetal fluids and tissues. The BHV-1 virus can become latent following a primary infection with a field isolate or vaccination with an attenuated strain. The viral genomic DNA has been demonstrated in the sensory ganglia of the trigeminal nerve in infectious bovine rhinotracheitis (IBR) and in sacral spinal ganglia in pustular vulvovaginitis and balanoposthitis cases. BHV-1 infections can be diagnosed by detection of virus or virus components and antibody by serological tests or by detection of genomic DNA by polymerase chain reaction (PCR), nucleic acid hybridization and sequencing. Inactivated vaccines and modified live virus vaccines are used for prevention of BHV-1 infections in cattle; subunit vaccines and marker vaccines are under investigation.
Surface-associated and secreted factors ofStreptococcus suisin epidemiology, pathogenesis and vaccine development
Authors: Baums Christoph Georg , Valentin-Weigand Peter
Published: June 2009

Streptococcus suisis an invasive porcine pathogen associated with meningitis, arthritis, bronchopneumonia and other diseases. The pathogen constitutes a major health problem in the swine industry worldwide. Furthermore,S. suisis an important zoonotic agent causing meningitis and other diseases in humans exposed to pigs or pork. Current knowledge on pathogenesis is limited, despite the enormous amount of data generated by ‘omics’ research. Accordingly, immunprophylaxis (in pigs) is hampered by lack of a cross-protective vaccine against virulent strains of this diverse species. This review focuses on bacterial factors, both surface-associated and secreted ones, which are considered to contribute toS. suisinteraction(s) with host factors and cells. Factors are presented with respect to (i) their identification and features, (ii) their distribution amongS. suisand (iii) their significance for virulence, immune response and vaccination. This review also shows the enormous progress made in research onS. suisover the last few years, and it emphasizes the numerous challenging questions remaining to be answered in the future.
Broadcasting but not receiving: density dependence considerations for SETI signals
Authors: Smith Reginald D.
Published: June 2009

This paper develops a detailed quantitative model which uses the Drake equation and an assumption of an average maximum radio broadcasting distance by an communicative civilization. Using this basis, it estimates the minimum civilization density for contact between two civilizations to be probable in a given volume of space under certain conditions, the amount of time it would take for a first contact, and the question of whether reciprocal contact is possible.
Knowledge and the theory of institutional change
Authors: EGGERTSSON THRÁINN
Published: June 2009

Modern theory identifies several sources of economic growth, such as capital accumulation, new techniques, secure property rights and contracts, and absence of rent seeking. This paper introduces new social technologies as yet another source of growth and emphasizes our incomplete knowledge of social systems. I introduce a framework for analyzing institutional policy and use the case of modern biotechnology to explain how uncertainty about social technologies, persuasion, and competing beliefs influence the evolution of property rights.
Comparing theories of institutional change
Authors: KINGSTON CHRISTOPHER , CABALLERO GONZALO
Published: June 2009

This article compares a variety of theoretical approaches to conceptualizing institutional change. Our goal is neither to discover the ‘best’ theory, nor to attempt to build a new one. Rather, we wish to compare how the theories we consider agree or differ with respect to the causes, process, and outcomes of institutional change. Some of the theories we discuss emphasize the deliberate creation of institutions through the political process, while others emphasize the spontaneous emergence of institutions through evolutionary processes. Still others combine elements of evolution and design. We differentiate a variety of approaches to conceptualizing the interaction between formal and informal rules. We discuss recent theories based on the ‘Equilibrium View’ of institutions, and theories emphasizing the role of habit, learning, and bounded rationality. We also consider theoretical explanations for institutional inertia and path-dependence.
Institutions and US regional development: a study of Massachusetts and Virginia
Authors: KIM SUKKOO
Published: June 2009

The development of the American economy was accompanied by significant spatial income inequalities between the northern and southern regions. While many factors contributed to northern industrialization and southern stagnation, an important factor was differences in the region's institutions. In the North, a democratic institution fostered growth whereas in the South, oligarchic institutions favored status quo. To gain insights on the nature and causes of this divergence, this paper examines the development of political and legal institutions in Massachusetts and Virginia, the two leading states in the North and the South.
Does institutional quality affect capital mobility? Evidence from developing countries
Authors: YOUNAS JAVED
Published: June 2009

This paper uses an augmented Feldstein–Horioka savings–investment methodology to examine the impact of institutional quality on the degree of capital mobility in developing countries. A high correlation between domestic investment and domestic savings can arise from the presence of institutional rigidities restricting the movement of capital across borders. We find that including different aspects of institutional quality raises the coefficient of the savings rate, implying lower capital mobility. However, the improvement in institutional quality that strengthens the legal system, reduces investment risks, and ensures democratic accountability, increases capital mobility in developing countries. Inclusion of foreign aid also has a positive impact on the coefficient of the savings rate.
Comparative urban institutions and intertemporal externality: a revisit of the Coase conjecture
Authors: DENG FENG
Published: June 2009

Coase originally formulated his conjecture about intertemporal price competition in an example of land monopoly, but it has been applied almost exclusively to non-spatial markets. This paper revisits the Coase conjecture and compares four institutional arrangements based on the combination of land tenure options and local governance forms: private/rental, public/rental, private/owner, and public/owner. The two-period model developed in this paper shows that homeownership may result in more land development than leasehold. Numeric examples suggest (1) public/owner is efficient for uniform distribution of consumer; (2) rentals can be desirable for ‘poor’ communities; (3) private/owner is more efficient for ‘rich’ communities; (4) restrictive zoning reduces social surplus. These results can help explain why public institutions are dominant in the urban area and why most private communities are small, located in the suburbs, and for middle-upper class.
Integrated on-chip antennas for communication on and between monolithic integrated circuits
Authors: Yordanov Hristomir , Russer Peter
Published: June 2009

The rate of signal transmission on or between monolithic integrated circuits is limited by the cross-talk and the dispersion due to the wired interconnects. The bandwidth limitations can be overcome by wireless chip-to-chip and on-chip interconnects via integrated antennas. In this work the utilization of the electronic circuit ground planes as radiating elements for the integrated antennas has been proposed. This allows for optimal usage of chip area, as the antennas share the same metallization structure as the circuits. By exciting the interconnects between the patch areas in transmission line modes as well as in antenna modes, the interference between signals from circuit to circuit and antenna excitation signals is minimized. This has been achieved by inserting a transformer in the antenna feeding network. Examples of possible antenna and feeding structures have been investigated numerically. Scaled prototypes of the integrated antennas have been manufactured and measured.
Die präoperative Evaluation beim elektiven Patienten
Authors: Bandschapp Oliver , Kaufmann Markus
Published: June 2009

Die präoperative Evaluation dient der Risikobeurteilung des Patienten mit dem Ziel einer Risikominimierung für den anschließenden operativen Eingriff. In Abhängigkeit von Systemanamnese, Befunden und geplantem Eingriff werden bei Bedarf weitergehende Abklärungen durchgeführt. Der klinische Zustand des Patienten wird, falls nötig, optimiert und das perioperative Vorgehen geplant. Der Patient wird über Anästhesie und perioperative Periode aufgeklärt. Das Einverständnis zum vereinbarten Anästhesieverfahren wird eingeholt. Leistungsfähige Patienten ohne Risikofaktoren können dank neuer Technologien einfacher und effizienter evaluiert werden.
Chronische Medikation im Vorfeld operativer Eingriffe: absetzen – beibehalten – ausbauen?
Authors: Buse Giovanna Lurati , Bucher Evelyne , Seeberger Manfred D. , Filipovic Miodrag
Published: June 2009

Damit die Patienten in einem möglichst stabilen Zustand zur Operation kommen, sollen alle Begleiterkrankungen optimal behandelt und medikamentös eingestellt sein. Entsprechend gilt heute die Empfehlung (fast) die gesamte chronische Medikation bis zum Vortag eines operativen Eingriffes unverändert weiterzugeben. Die präoperative Phase soll darüber hinaus zum Anlass genommen werden, die Güte der chronischen Medikation zu überdenken. Sind alle internistisch-kardiologischen Indikationen für den Einsatz von β-Rezeptor-Blockern, ACE-Hemmern und Statinen ausgeschöpft? Ist der Diabetes bestmöglich eingestellt, die Therapie der Schilddrüsen-Dysfunktion noch optimal? Ergibt sich ein Handlungsbedarf, sollen die Anpassungen möglichst frühzeitig vorgenommen und die Dosierungen sorgfältig titriert werden. Einzig im Hinblick auf einen bevorstehenden Eingriff sollen hingegen keine ansonsten nicht indizierte Therapien begonnen werden. Der Umgang mit gerinnungshemmenden Substanzen verlangt nach einem differenzierten Vorgehen. Hier muss die Indikation für die Therapie genauso beachtet werden wie die Gefährlichkeit allfälliger Blutungskomplikationen. Nach akuten kardiovaskulären Ereignissen, insbesondere nach perkutaner Koronarintervention, müssen bis zur Durchführung von (Wahl-) Operationen wenn immer möglich Wartezeiten eingehalten werden, deren Dauer je nach Ereignis und Behandlungsmodalität zwischen wenigen Wochen bis zu einem Jahr liegt.
Präoperative Abklärungen bei Patienten mit neurologischen Erkrankungen
Authors: Czarnetzki Christoph , Tramèr Martin
Published: June 2009

Patienten mit neurologischen Erkrankungen müssen sich häufig erkrankungsspezifischen chirurgischen Eingriffen unterziehen. Dazu gehören zum Beispiel orthopädische Eingriffe (Tenotomien, Positionskorrekturen von Gelenken), urologische Eingriffe bei Sphinkterstörungen, ORL Eingriffe (Tracheotomie), und plastisch-chirurgische Eingriffe für die Versorgung von Wunddefekten. Präoperativ sollten diese Patienten sorgfältig abgeklärt werden. Spezifische Untersuchungen, zum Beispiel Lungenfunktionstests, können insbesondere bei Patienten, welche sich einem Oberbauch- oder Thoraxeingriff unterziehen müssen, nützlich sein. Eine enge Zusammenarbeit zwischen behandelndem Arzt und Anästhesisten ist dabei wünschenswert. Prinzipiell kann nicht ausgeschlossen werden, dass sich die Symptome einer neurologischen Erkrankung, bedingt durch Anästhesie, Chirurgie oder ganz allgemein perioperativen Stress, verschlechtern. Medikamente, welche zur Behandlung einer neurologischen Erkrankung eingenommen werden, sollten präoperativ nicht abgesetzt werden.
Präoperative Vorbereitung von Patienten mit Herz- und Gefäßkrankheiten für nicht-herzchirurgische Eingriffe
Authors: Doser Martin , Eberle Balthasar
Published: June 2009

Die präoperative Vorbereitung von Patienten mit Herz- und Gefäßkrankheiten wird mit Vorteil bereits vom Hausarzt eingeleitet. Für die perioperative Evaluation und Behandlung vor nicht-herzchirurgischen Operationen stehen aktuelle Richtlinien der American Heart Association und des American College of Cardiology (2007) zur Verfügung: Der Abklärungsgang wird anhand der Aktivität der kardialen Erkrankung, der körperlichen Leistungsfähigkeit, weiterer kardialer Risikoindikatoren und dem Risiko des Eingriffes festgelegt. Der stabile, asymptomatische, körperlich belastbare Patient kann in der Regel ohne weitere Vordiagnostik zur elektiven Anästhesie und Operation überwiesen werden. Bei Vorliegen einer aktiven kardialen Erkrankung muss eine Elektiv-OP verschoben und die fachkardiologische Versorgung vorgezogen werden. Der stabile Patient mit eingeschränkter (< 4 metabolische Äquivalente, MET) oder nicht bekannter Leistungsfähigkeit und klinischen Risikoindikatoren bedarf vor Eingriffen mit mittlerem oder großem Risiko einer erweiterten kardialen Vorbereitung. Bereits bestehende, indizierte Therapien mit Betablockern und Statinen sollen weitergeführt werden; die Einleitung einer Betablockertherapie (Zielherzfrequenz < 65/min) kann erforderlich werden je nach Eingriffsrisiko, Vorliegen einer koronaren Herzkrankheit und Anzahl kardialer Risikoindikatoren. Bei Patienten nach vorgängiger perkutaner koronarer Intervention sind vor Elektiveingriffen zeitliche Mindestabstände zwingend einzuhalten. Bei der Entscheidung über Fortführung oder Absetzen einer medikamentösen Thrombozytenaggregationshemmung sind eingriffstypische Blutungrisiken sorgfältig gegen das Risiko perioperativer kardio- oder zerebrovaskulärer Ischämien abzuwägen.
Präoperative Betreuung des nierenkranken Patienten
Authors: Ott Alexander , Rehli-Bürgler Melanie
Published: June 2009

Ein Großteil der Patienten mit chronischen Nierenerkrankungen unterzieht sich im Laufe seines Lebens einem operativen Eingriff. Eine optimale präoperative Vorbereitung, beginnend in der Hausarztpraxis, trägt zu einer Senkung der perioperativen Morbidität und Mortalität bei. Die Kenntnis der physiologischen und pathophysiologischen Zusammenhänge ist eine wichtige Voraussetzung zum Verständnis der perioperativen Risiken dieser Patientengruppe. Insbesondere das Nierenmark mit seiner schon unter normalen Bedingungen ausgeschöpften Sauerstoffversorgung, ist für anästhesiologische und operative Einflüsse besonders anfällig. Das Hauptaugenmerk der Anästhesieführung gilt der Vermeidung einer Hypoperfusion der Nieren und der damit verbundenen Gefahr einer postoperativen Nierendysfunktion. Ein leicht zu bestimmender und aussagekräftiger Parameter zu Beurteilung der Nierenfunktion ist die Glomeruläre Filtrationsrate (GFR). Mit Hilfe einfacher Formeln (Cockroft-Gault, MDRD „Modification of Diet in Renal Disease“) lässt sich stellvertretend für die GFR, die Kreatinin-Clearance, als Maß für die Funktion der Niere schätzen. Die häufig angewendete alleinige Bestimmung der Kreatininkonzentration im Serum ist hierfür nicht ausreichend. Anhand der GFR werden Nierenerkrankungen in verschiedene Stadien eingeteilt und entsprechend behandelt. Die Kenntnis einer eingeschränkten Nierenleistung ist für die Dosierung und Wirkung anästhesierelevanter Medikamente von Bedeutung. Weitere wichtige Parameter zur Einschätzung der Auswirkungen der Funktionseinschränkung sind die Messung des Hämoglobinwertes, sowie der Serumkonzentrationen der Elektrolyte Natrium und Kalium. Elektive operative Eingriffe sollten, wenn möglich, in einer stabilen Phase des Krankheitsverlaufes stattfinden. Eine adäquate und ausreichende Behandlung der Begleiterkrankungen, wie zum Beispiel einer arteriellen Hypertonie, sind notwendig und tragen zu einer Verminderung postoperativen Nierenfunktionsstörungen bei. Bei Unklarheiten im Vorfeld einer geplanten Operation lohnt sich die Kontaktaufnahme mit dem zuständigen Anästhesisten, um eine kurzfristige Verschiebung der Intervention zu vermeiden.
Präoperative Vorbereitung von Patienten mit endokrinologischen Erkrankungen
Authors: Studer Wolfgang , Fahrner Karina
Published: June 2009

Grundsätzlich sind Patienten mit endokrinologischen Erkrankungen Kandidaten für eine frühe anästhesiologische Beurteilung. Dies gilt insbesondere für die häufigen Erkrankungen wie Diabetes mellitus, Adipositas und Schilddrüsenerkrankungen aufgrund des Potentials der präoperativen Optimierung und der Bereitstellung der benötigten Infrastruktur. Bei den selteneren Erkrankungen ist wichtig, dass dem betreuenden Anästhesieteam durch die frühe präoperative Beurteilung Zeit zur Informationsbeschaffung und Zugang zu spezialisiertem Wissen ermöglicht wird.
Betreuung und präoperative Bewertung für die Anästhesie der schwangeren Frau
Authors: Thierrin Laurent , Schoettker Patrick , Kern Christian
Published: June 2009

Die Schwangerschaft wird von bedeutenden anatomischen und physiologischen Veränderungen begleitet, desgleichen auch von spezifischen Komplikationen, wobei es wichtig ist, dass diese von den praktizierenden Ärzten erkannt werden. Schwangere Patientinnen können in zwei verschiedenen Situationen eine Anästhesie benötigen: für einen geplanten chirurgischen Eingriff (ungefähr 1% der Schwangerschaften) oder, wie in den meisten Fällen, für die Geburtshilfe (Schmerzlinderung, Sectio caesarea, Blutungen und deren Komplikationen). Bestimmte Krankheitsbilder benötigen ein spezifisches anästhesiologisches Verfahren oder eine geplante multidisziplinäre Zusammenarbeit. Es ist deshalb von größter Wichtigkeit, dass der Arzt risikoreiche Situationen erkennt, um die Patientinnen rechtzeitig an Spezialisten zu verweisen.
Seasonal cycle of seawater bromoform and dibromomethane concentrations in a coastal bay on the western Antarctic Peninsula
Authors: Hughes Claire , Chuck Adele L. , Rossetti Helen , Mann Paul J. , Turner Suzanne M. , Clarke Andrew , Chance Rosie , Liss Peter S.
Published: June 2009

Sea‐to‐air emissions of bromocarbon gases are known to play an important role in atmospheric ozone depletion. In this study, seawater concentrations of bromoform (CHBr3) and dibromomethane (CH2Br2) were measured regularly between February 2005 and March 2007 at the Rothera Oceanographic and Biological Time Series (RaTS) site located in Marguerite Bay on the Antarctic Peninsula. Strong seasonality in CHBr3 and CH2Br2 concentrations was observed. The highest bromocarbon concentrations (up to 276.4 ± 13.0 pmol CHBr3 L−1 and 30.0 ± 0.4 pmol CH2Br2 L−1) were found to coincide with the annual microalgal bloom during the austral summer, with lower concentrations (up to 39.5 pmol CHBr3 L−1 and 9.6 ± 0.6 pmol CH2Br2 L−1) measured under the winter fast ice. The timing of the initial increase in bromocarbon concentrations was related to the sea‐ice retreat and onset of the microalgal bloom. Observed seasonal variability in CH2Br2/CHBr3 suggests that this relationship may be of use in resolving bromocarbon source regions. Mainly positive saturation anomalies calculated for both the 2005/2006 and 2006/2007 summers suggest that the bay was a source of CHBr3 and CH2Br2 to the atmosphere. Estimates of bromocarbon sea‐to‐air flux rates from Marguerite Bay during ice‐free periods are 84 (−13 to 275) CHBr3 nmol m−2 d−1 and 21 (2 to 70) nmol CH2Br2 m−2 d−1. If these flux rates are representative of the seasonal ice edge zone bloom which occurs each year over large areas of the Southern Ocean during the austral summer, sea‐to‐air bromocarbon emissions could have an important impact on the chemistry of the Antarctic atmosphere.
Origins of chemical diversity of back‐arc basin basalts: A segment‐scale study of the Eastern Lau Spreading Center
Authors: Bézos Antoine , Escrig Stéphane , Langmuir Charles H. , Michael Peter J. , Asimow Paul D.
Published: June 2009

We report major, trace, and volatile element data on basaltic glasses from the northernmost segment of the Eastern Lau Spreading Center (ELSC1) in the Lau back‐arc basin to further test and constrain models of back‐arc volcanism. The zero‐age samples come from 47 precisely collected stations from an 85 km length spreading center. The chemical data covary similarly to other back‐arc systems but with tighter correlations and well‐developed spatial systematics. We confirm a correlation between volatile content and apparent extent of melting of the mantle source but also show that the data cannot be reproduced by the model of isobaric addition of water that has been broadly applied to back‐arc basins. The new data also confirm that there is no relationship between mantle temperature and the wet melting productivity. Two distinct magmatic provinces can be identified along the ELSC1 axis, a southern province influenced by a “wet component” with strong affinities to arc volcanism and a northern province influenced by a “damp component” intermediate between enriched mid‐ocean ridge basalts (E‐MORB) and arc basalts. High–field strength elements and rare earth elements are all mobilized to some extent by the wet component, and the detailed composition of this component is determined. It differs in significant ways from the Mariana component reported by E. Stolper and S. Newman (1994), particularly by having lower abundances of most elements relative to H2O. The differences can be explained if the slab temperature is higher for the Mariana and the source from which the fluid is derived is more enriched. The ELSC1 damp component is best explained by mixing between the wet component and an E‐MORB‐like component. We propose that mixing between water‐rich fluids and low‐degree silicate melts occurs at depth in the subduction zone to generate the chemical diversity of the ELSC1 subduction components. These modified sources then rise independently to the surface and melt, and these melts mix with melts of the background mantle from the ridge melting regime to generate the linear data arrays characteristic of back‐arc basalts. The major and trace element framework for ELSC1, combined with different slab temperatures and compositions for difference convergent margins, may be able to be applied to other back‐arc basins around the globe.
Brittle versus ductile deformation as the main control on the transport properties of low‐porosity anhydrite rocks
Authors: De Paola N. , Faulkner D. R. , Collettini C.
Published: June 2009

An experimental approach has been taken to study the prefailure fluid flow properties of borehole samples of low‐porosity anhydrites and the evolution of permeability (k) during deformation leading to brittle and ductile failure. The permeability measured under hydrostatic stress conditions prior to loading at room temperature is generally low (k = 10−21–10−19 m2) and displays an anisotropy and pressure sensitivity controlled by grain size and fabric orientation (foliation). Triaxial loading test results show that the brittle‐ductile transition occurs for effective pressure Pe < 20 MPa and is almost independent of fabric orientation and grain size. All samples, whether deforming in a brittle (localized deformation) or ductile (distributed deformation) mode, show dilatancy after an initial phase of compaction. During loading, the k starts to increase prior to the phase of sample dilation and before the yield stress is attained. The k rise is characterized by an upward concave trend, prior to localized deformation (brittle failure), and by a downward concave trend, during distributed deformation (ductile failure). The k increase prior to brittle failure is about 1 order of magnitude higher than during ductile failure. We interpret the different shape of the k curve as due to the observed different degrees of fracture connectivity (widespread development of intragranular and intergranular fractures) reached during brittle (low) and ductile (high) deformation, respectively. Our experimental results imply that for low‐porosity rocks the mode of failure, controlled by Pe, has an overwhelming effect on the evolution of permeability, compared to other factors such as grain size and fabric orientation.
Processes that generate and deplete liquid water and snow in thin midlevel mixed‐phase clouds
Authors: Smith Adam J. , Larson Vincent E. , Niu Jianguo , Kankiewicz J. Adam , Carey Lawrence D.
Published: June 2009

This paper uses a numerical model to investigate microphysical, radiative, and dynamical processes in mixed‐phase altostratocumulus clouds. Three cloud cases are chosen for study, each of which was observed by aircraft during the fifth or ninth Complex Layered Cloud Experiment (CLEX). These three clouds are numerically modeled using large‐eddy simulation (LES). The observed and modeled clouds consist of a mixed‐phase layer with a quasi‐adiabatic profile of liquid, and a virga layer below that consists of snow. A budget of cloud (liquid) water mixing ratio is constructed from the simulations. It shows that large‐scale ascent/descent, radiative cooling/heating, turbulent transport, and microphysical processes are all significant. Liquid is depleted indirectly via depositional growth of snow (the Bergeron‐Findeisen process). This process is more influential than depletion of liquid via accretional growth of snow. Also constructed is a budget of snow mixing ratio, which turns out to be somewhat simpler. It shows that snow grows by deposition in and below the liquid (mixed‐phase) layer, and sublimates in the remainder of the virga region below. The deposition and sublimation are balanced primarily by sedimentation, which transports the snow from the growth region to the sublimation region below. In our three clouds, the vertical extent of the virga layer is influenced more by the profile of saturation ratio below the liquid (mixed‐phase) layer than by the mixing ratio of snow at the top of the virga layer.
Formation and preservation of greigite (Fe3S4) in sediments from the Santa Barbara Basin: Implications for paleoenvironmental changes during the past 35 ka
Authors: Blanchet C. L. , Thouveny N. , Vidal L.
Published: June 2009

Diagenetic processes are known to modify sedimentary records, but they can also reveal important paleoenvironmental changes. Here we investigate variations in sedimentary iron diagenesis and depositional environments for the last 35 ka by analyzing the rock magnetic and geochemical properties of two sediment cores collected in the Santa Barbara Basin (California). In organic‐rich sediments, early diagenesis often leads to partial dissolution of detrital iron oxides and stepwise formation of authigenic pyrite (FeS2). The pyritization process takes place following several geochemical pathways, sometimes involving intermediate iron sulfide species such as greigite (Fe3S4). Sedimentary conditions in the basin appear to have recurrently favored preservation of greigite (identified by its magnetic properties) and inhibited its complete transformation into pyrite. The Holocene interval contains a series of centimeter‐thick greigite‐bearing layers that are associated with large flood deposits, which are known in the basin as “gray layers.” We propose that greigite preservation was enabled in these sediments by their relative enrichment in reactive iron over organic matter and/or hydrogen sulfide (because of their high ratio of terrigenous over organic material), which limited pyritization reactions. Within the glacial deposits, formation and preservation of meter‐thick greigite layers occurred in terrigenous‐rich and organic‐poor sedimentary layers and is proposed to result from a similar diagenetic process to that in the Holocene greigite‐bearing layers (dominance of reactive iron over organic matter and/or HS−). The terrigenous enrichments in the glacial greigite‐bearing layers are probably related to climatic or sea level changes because they occur at times of massive iceberg releases in the North Atlantic, the so‐called Heinrich events.
Determining the start, duration, and strength of flood and drought with daily precipitation: Rationale
Authors: Lu Er
Published: June 2009

Determinations of the start, duration, and strength of flood and drought are important in the operational monitoring and to decision‐makers, but cannot be made through the commonly‐used Standardized Precipitation Index. Physical considerations are provided in this note for measuring the daily flood and drought extent with precipitation. The rationale is that, because of the memory of the soil‐land surface system, the flood and drought extent of a day is contributed by the precipitation of both the day and the earlier days, while the contribution of the earlier day precipitation is decayed due to the demands of the water balance, including the runoff, evapotranspiration, and percolation. The proposed index has the same unit and magnitude as precipitation, and is easy to calculate. It can be used to evaluate the interannual variabilities and long‐term changes of the start, duration, and strength of flood and drought.
Evidence of enhanced turbulent dissipation in the frontogenetic Kuroshio Front thermocline
Authors: Nagai Takeyoshi , Tandon Amit , Yamazaki Hidekatsu , Doubell Mark J.
Published: June 2009

Enhanced turbulent dissipation, O(10−8–10−7) Wkg−1 in the thermocline on the cyclonic side of the Kuroshio Front was observed during a period of frontogenesis, using a microstructure profiler, XBT and ADCP along 143°E across the Kuroshio Front in August 2008. The eddy diffusivity corresponding to the mixing below the central jet is estimated to be O(10−4–10−3) m2 s−1. The strong turbulent mixing we observed in the Kuroshio is in sharp contrast to previous field measurements which found that small scale diapycnal mixing in western boundary currents remains at levels typically measured in the open ocean thermocline. The turbulence in the Kuroshio is attributed to frontogenesis arising out of an estimated confluence rate of O(10−5) s−1 based on satellite altimeters, suggesting the ubiquity of a forward energy cascade from mesoscale to microscale turbulence near ocean fronts as indicated by recent theoretical studies.
Future change in wintertime atmospheric blocking simulated using a 20‐km‐mesh atmospheric global circulation model
Authors: Matsueda Mio , Mizuta Ryo , Kusunoki Shoji
Published: June 2009

Future change in the frequency of atmospheric blocking is investigated through present‐day (1979–2003) and future (2075–2099) simulations using 20‐, 60‐, 120‐, and 180‐km‐mesh atmospheric general circulation models (AGCMs) under the Intergovernmental Panel on Climate Change Special Reports on Emission Scenarios A1B emission scenario, focusing on the Northern Hemisphere winter (December–February). The results of present‐day climate simulations reveal that the AGCM with the highest horizontal resolution is required to accurately simulate Euro‐Atlantic blocking, whereas the AGCM with the lowest horizontal resolution is in good agreement with reanalysis data regarding the frequency of Pacific blocking. While the lower‐resolution models accurately reproduce long‐lived Pacific blocking, they are unable to accurately simulate long‐lived Euro‐Atlantic blocking. This result suggests that the maintenance mechanism of Euro‐Atlantic blocking is different from that of Pacific blocking. In the future climate simulations, both frequencies of Euro‐Atlantic and Pacific blockings are predicted to show a significant decrease, mainly in the western part of each peak in present‐day blocking frequency, where the westerly jet is predicted to increase in strength; no significant change is predicted in the eastern part of each peak. The number of Euro‐Atlantic blocking events is predicted to decrease for almost all blocking durations, whereas the decrease in the number of Pacific blockings is remarkable for long‐duration events. It is possible that long‐lived (>25 days) Euro‐Atlantic and Pacific blockings will disappear altogether in the future.
Mexican American Mothers of Low and Middle Socioeconomic Status: Communication Behaviors and Interactive Strategies During Shared Book Reading
Authors: Rodríguez Barbara L. , Hines Rachel , Montiel Miguel
Published: June 2009

Purpose

The aim of this investigation was to describe and compare the communication behaviors and interactive reading strategies used by Mexican American mothers of low- and middle-socioeconomic status (SES) background during shared book reading.

Method

Twenty Mexican American mother–child dyads from the Southwestern United States were observed during two book reading sessions. The data were coded across a number of communication behavior categories and were analyzed using the Adult/Child Interactive Reading Inventory (ACIRI; A. DeBruin-Parecki, 1999 ).

Results

Mexican American mothers used a variety of communication behaviors during shared book reading with their preschool children. Significant differences between the SES groups regarding the frequency of specific communication behaviors were revealed. Middle-SES mothers used positive feedback and yes/no questions more often than did low-SES mothers. Mexican American mothers also used a variety of interactive reading strategies with varying frequency, as measured by the ACIRI. They enhanced attention to text some of the time, but rarely promoted interactive reading/supported comprehension or used literacy strategies. There were no significant differences between the SES groups regarding the frequency of interactive reading strategies.

Conclusion

Parent literacy programs should supplement Mexican American mothers' communication behaviors and interactive reading strategies to improve effectiveness and participation.
Derivational Morphophonology: Exploring Errors in Third Graders' Productions
Authors: Jarmulowicz Linda , Hay Sarah E.
Published: June 2009

Purpose

This study describes a post hoc analysis of segmental, stress, and syllabification errors in third graders' productions of derived English words with the stress-changing suffixes -ityand-ic. We investigated whether (a) derived word frequency influences error patterns, (b) stress and syllabification errors always co-occur, and (c) derived word stress pattern affects errors.

Method

A total of 1,900 productions from 81 third-grade children were transcribed and coded. The targets were 8 high-frequency (HF) and 8 low-frequency (LF) real English words and 8 nonsense (NS) derived words. Participants combined a suffix and a base word to produce a derived word. The vowel-initial suffixes required both stress and syllabic changes in a base word.

Results

Children made more segmental and stress errors on NS words than on HF and LF words, but more syllabification errors on LF words than on HF and NS words. More items among the LF words required vowel alternations than among the HF words. When syllabification was not mastered, stress was usually incorrect; however, when syllabification was correct, children often still erred on stress. Derived words that contained 2 trochaic feet were produced with fewer errors than were those that only had 1 trochaic foot.

Conclusion

Rather than a frequency effect, a lexical effect emerged such that real words were more similar to each other for segmental and stress errors than they were to NS words. Three findings suggest that prosody plays a role in errors: Children made more suprasegmental than segmental errors, they appeared to master syllabification before stress placement, and they produced fewer errors on derived words with 2 trochaic feet than on those with only 1 trochaic foot. Although these results are preliminary, they highlight the role of prosody in morphophonology.
Integrated Morphological Awareness Intervention as a Tool for Improving Literacy
Authors: Kirk Cecilia , Gillon Gail T.
Published: June 2009

Purpose

This study evaluated the effects of an intervention program aimed to improve reading and spelling ability through instruction in morphological awareness together with other forms of linguistic awareness, including knowledge of phonology, orthography, syntax, and semantics.

Method

Sixteen children aged between 8;07 (years;months) and 11;01 who demonstrated specific spelling difficulties were randomly assigned to either an experimental or a control group. Participants received an average of 19.4 sessions of intervention that focused on increasing awareness of the morphological structure of words, with particular attention to the orthographic rules that apply when suffixes are added to the base word.

Results

Participants in the experimental group made significantly greater gains in reading and spelling accuracy than those in the control group on both experimental and standardized measures of reading and spelling. The results also show that participants were able to generalize to new words what they had learned in the intervention sessions.

Conclusion

Practitioners should consider the likely benefits of literacy intervention that focuses on developing morphological awareness in conjunction with other types of linguistic awareness.
Teaching Students With Reading Difficulties to be Close Readers: A Feasibility Study
Authors: Katz Lauren A. , Carlisle Joanne F.
Published: June 2009

Purpose

This article describes a program that was designed to help upper elementary students read and understand words as they read texts independently. As a first step in helping middle-to-upper elementary children with mild-to-moderate language and/or reading difficulties engage in textual analysis during reading, the Close Reading program combines instruction in morphological-analysis and context-analysis strategies with guided experiences applying these strategies during reading.

Method

To carry out an initial feasibility study of the program, we conducted 3 case studies using standardized pretest and posttest measures of language and reading skills and experimental progress monitoring measures administered before, during, and after instruction. Three fourth-grade girls participated in the 12-week program.

Results

All 3 students showed improved word reading and comprehension with small to large effect sizes on standardized and experimental measures. Patterns of improvement reflected the initial strengths and weaknesses of the students' reading and language skills.

Conclusion

The results suggest that further experimental investigation of this program is warranted. Instruction in morphological-analysis strategies with guided practice during reading holds promise as a way to improve word reading and comprehension for struggling readers in the middle-to-upper elementary years.
The Influence of Morphological Awareness on the Literacy Development of First-Grade Children
Authors: Wolter Julie A. , Wood Alexis , D’zatko Kim W.
Published: June 2009

Purpose

The purpose of this study was twofold. First, we investigated whether first-grade children evidenced morphological awareness and whether they used their knowledge of morphological relations to guide their spelling. Second, we sought to determine whether children’s morphological awareness abilities were predictive of their performance on word-level reading and spelling measures.

Method

At the beginning of the academic school year, 43 first-grade children were administered an oral morphological awareness production task, a series of single-word morphological spelling tasks, and a battery of language and literacy tasks.

Results

The first-grade children were able to generate words reflecting morphological relations before they received explicit instruction regarding morphological relations between words. In addition, the children used morphological information to guide their spelling of single words, as evidenced by a difference in patterns of spellings between 1- and 2-morpheme words. Regression analyses revealed that the children’s performance on the oral morphological production task explained unique variance on their reading and spelling measures above and beyond the variance that was accounted for by phonological awareness.

Conclusion

Children as young as first graders evidenced morphological awareness, and morphological awareness influenced the children’s literacy development. Theoretical implications of the findings are discussed.
Morphological Awareness Skills of Fourth-Grade African American Students
Authors: Apel Kenn , Thomas-Tate Shurita
Published: June 2009

Purpose

We examined the morphological awareness skills of fourth-grade African American children and the association between degree of African American English (AAE) use and performance on written measures of morphological awareness. Additional purposes were to determine whether performance on the morphological awareness tasks (a) was affected by the transparency of morphologically related words and the type of task administered, (b) was associated with other literacy and literacy-related skills, and (c) explained unique variance on these latter abilities.

Method

Thirty fourth-grade African American children from low-income backgrounds were administered 2 morphological awareness tasks and completed norm-referenced measures of word-level reading, reading comprehension, spelling, phonemic awareness, and receptive vocabulary.

Results

The degree of AAE use was not associated with students' performance on the morphological awareness tasks. On these tasks, significantly higher scores were obtained on items that represented a transparent relationship between a base word and its derived form. The students' performance on the morphological awareness tasks was significantly and moderately related to their performance on the word-level reading, spelling, and receptive vocabulary measures. Morphological awareness scores explained significant unique variance on measures of word-level reading and spelling, above that predicted by performance on measures of phonemic awareness and vocabulary.

Conclusion

As shown in previous investigations of Caucasian children’s morphological awareness skills, fourth-grade African American students' morphological awareness abilities are associated with select language and literacy skills. Professionals should capitalize on students' intact capabilities in morphological awareness during literacy instruction in an effort to maximize language and literacy performance for African American students.
A Survey of University Professors Teaching Speech Sound Disorders: Nonspeech Oral Motor Exercises and Other Topics
Authors: Watson Maggie M. , Lof Gregory L.
Published: June 2009

Purpose

The purpose of this article was to obtain and organize information from instructors who teach course work on the subject of children’s speech sound disorders (SSD) regarding their use of teaching resources, involvement in students' clinical practica, and intervention approaches presented to students. Instructors also reported if they taught students to use nonspeech oral motor exercises (NSOMEs) to remediate children’s SSD.

Method

A questionnaire was mailed to 236 speech-language pathology preprofessional programs in the United States that are accredited by the Council of Academic Accreditation.

Results

Ninety-one questionnaires (39%) were returned. Participants reported that they provided their students with information on a variety of intervention approaches for SSD and typically used professional journals and textbooks for current information. Sixty-eight (75%) paticipants reported that they did not teach their students to use NSOMEs. Forty-seven (52%) of the instructors supervised students in clinical practicum serving children with SSD and perceived that academic course work and practicum experiences influenced their students' implementation of intervention for children with SSD.

Conclusion

The instructors reported that they taught their students a variety of intervention techniques for children with SSD, although most did not teach the use of NSOMEs. These results contrast with previous research indicating that many speech-language pathologists use NSOMEs to improve children’s speech (G.L. Lof & M.M. Watson, 2008).
Morphology and Literacy: Getting Our Heads in the Game
Authors: Green Laura
Published: June 2009

Purpose

This prologue introduces the clinical forum, briefly discusses the importance of morphology in literacy, and informs the reader of the scope of the included articles.

Method

The concept of morphology is reviewed, contributing authors are introduced, and a brief summary of each of the 5 forum articles is provided.

Conclusion

The studies in this forum investigated different morphological skills in a variety of contexts, at a variety of grade levels, and from a variety of perspectives, enabling the reader to learn more about morphological awareness developmentally, linguistically, and clinically.