bluuebunny/crossref_metadata_2025 huggingface dataset:
The impact of extreme run‐off events from the Sakasagawa river on the Senjogahara ecosystem, Nikko National Park. IV. Changes in tree and understory vegetation distribution patterns from 1982 to 1992
Authors: Hukusima Tukasa , Yoshikawa Masato
Published: November 2006

In this study, a survey was made of a sample area adjacent to Senjogahara moor, Nikko National Park, in central Japan, to discover the change of vegetation over the 10 years from 1982 to 1992. The sample area, which is dominated by Malus toringo, has often suffered alluvial deposition from flooding of the river. The accumulation depth of alluvial materials deposited for 1984–1987 were measured at 266 points in the area, and for 1987–1992 at 347 points. Each tree species showed its own changing pattern of distribution area in relation to the accumulation depth of alluvial deposits. For example, M. toringo showed an increase in the number of trunks, and extended its distribution area in spite of heavy deposition, whereas Betula platyphylla var. japonica and Larix kaempferi shifted their distribution to the area that suffered only light deposition. The distribution area of shrubby and herbaceous species of understory vegetation also showed different patterns of change. In addition, the recovery of bare ground by understory vegetation was by different species in heavily and in lightly deposited areas. These facts show that there is a difference in the tolerance of different species to burial by alluvial deposits, and this difference is an important factor in successional change and mosaic formation of vegetation in a repeatedly disturbed area.
Density effects on life‐history traits of an island lizard population
Authors: Hasegawa Masami
Published: November 2006

Long‐term monitoring of life‐history traits and the effects of density upon them were studied in an island population of the lizard Eumeces okadae. Although life‐history traits such as clutch size, egg size and the proportion of mature reproductive females varied little over 7 years in the intact population, manipulation of density to simulate decreased population density enhanced juvenile growth rate, age at first reproduction, frequency of female reproduction and size‐specific clutch mass. In particular, the proportion of mature females reproducing annually increased almost 10 times from 5.6% to 53.8% after the removal of some lizards. However, body size at first reproduction and egg size were almost identical under both high and low density conditions. This study suggests that there were strong density‐dependent effects on several life‐history traits and that E. okadae attained a density close to the carrying capacity of the environment.
Dispersion pattern and mortality of seeds and seedlings of Fagus crenata Blume in a cool temperate forest in western Japan
Authors: Akashi Nobuhiro
Published: November 2006

The seed and seedling mortality of Fagus crenata Blume after a mast year (1993) was examined in relation to density and distance from the nearest conspecific adult tree in a mixed conifer‐hardwood forest in Ohdaigahara, western Japan. The mortality of fallen seeds during winter amounted to 93.7%, and 79.2% of the current‐year seedlings died in the first growing season. The most important factor of death for both seeds and seedlings was predation by vertebrates. The mortality of seeds during winter was positively correlated with sound seed density. The mortality of seedlings was positively correlated with density but not significantly related to the distance from the nearest crown edge of a conspecific adult tree. Mortality patterns varied with stages and spatial scales due to the behavior of predators; it is thus important to investigate the spatial pattern of seeds and seedling mortality at various temporal and spatial scales. After the first growing season, the difference in seedling density between distance classes was not significant at <4m from the nearest adult trees due to density‐dependent mortality. However, seedling density was significantly lower in the ≥4 m class than in the <4 m classes.
Species diversity of Chinese beech forests in relation to warmth and climatic disturbances
Authors: Cao Kun‐Fang , Peters Rob
Published: November 2006

The trends in the occurrence of climatic disturbances in the Chinese Fagus range are described, and the relationship between woody species diversity and climatic factors in eight old‐growth Chinese beech forests is characterized. In the Chinese Fagus range that lies in the humid mountains of southern China, wind storms and heavy rain frequency increase towards the eastern coast. Thunderstorm frequency increases southwards. Snowfall frequency increases northwards. Glaze storm frequency peaks in the center near Lake Dongtian, but much higher in the east than in the west. Hailstorm frequency also peaks in the center. The forests sampled in this study are widely separated. Their canopies consist of either deciduous broad‐leaved trees or a mixture of evergreen and deciduous broad‐leaved trees. Their species diversity increases towards warmer sites and towards the east. The importance of the evergreen trees in relation to warmth and minimum temperature increases southwards. Our analysis suggests that wind storms and heavy rains enhance the species diversity of Chinese beech forests. Cold disturbances such as glaze and snow diminish the diversity and canopy dominance of evergreen broad‐leaved trees but favor deciduous broad‐leaved trees, especially beech. The annual precipitation received by the forests in this study varies from 1400–2550 mm. This is not correlated with diversity, however, probably because all of these forests grow in humid conditions with sufficient water being supplied by precipitation throughout the year.
Simulated removal trapping considered in connection with actual census data in small mammals
Authors: Tanaka Ryo
Published: November 2006

A record of simulated removal trapping of 50 samples drawn from N=50 under a design has been considered as to how it does contribute to practical censuses of small mammals. It follows that, for ordinary‐density populations so far experienced, the removal census based on the theory may frequently lead to quite wrong estimates from single‐plot data by the simplest method, and that the maximum likelihood method is doubtless better, but even this method may produce right estimates in about half of the cases, their standard error being of limited availability. Therefore pooling of data from many plots are desirous for such populations.
Ecological studies on the population of isaza, Chaenogobius Isaza Tanaka, in Lake Biwa, with special reference to the effects of population density upon its growth
Authors: Nagoshi Makoto
Published: November 2006

In order to get the knowledge on the age composition of “isaza” population in Lake Biwa and the effect of population density on growth, monthly distribution of mean body length and mean body weight has been analyzed on the basis of monthly haul by “isazabiki” trawl during 1949 to 1953 and also 1960 to 1965.

There is no apparent sex difference in the growth in the first and second years of life.

“Isaza” population is composed of two age groups, age 0 and 1 groups (1+fish), the latter occupying by far the greater part in commercial catch.

During the growth season fishes of both ages feed mainly on zooplankton, though in winter frequently take chironomid larvae, gammaridae and others in volume.

The growth season falls in the period from April to October in both age groups.

A considerable yearly variation occurring in growth is in close connection with the fluctuation of population density of all ages.

The influence affected by the density of age 1 group is larger than that by age 0 group.
Formal techniques for performance analysis: blending SAN and PEPA
Authors: Hillston Jane , Kloul Leïla
Published: November 2006

In this paper we consider two performance modelling techniques from the perspectives of model construction, generation of an underlying continuous time Markov process, and the potential for reduction in the Markov process. Such careful comparison of modelling techniques allows us to appreciate the strengths and weaknesses of different approaches, and facilitates cross-fertilization between them. In the present case we take a characteristic of one formalism, functional rates in Stochastic Automata Networks, and introduce it to the other formalism, Performance Evaluation Process Algebra. We investigate the benefits of this cross-fertilization, particularly from the perspectives of Markov process generation and reduction.
Being Silenced: The Impact of Negative Social Reactions on the Disclosure of Rape
Authors: Ahrens Courtney E.
Published: November 2006

Rape survivors who speak out about their assault experiences are often punished for doing so when they are subjected to negative reactions from support providers. These negative reactions may thereby serve a silencing function, leading some rape survivors to stop talking about their experiences to anyone at all. The current study sought to examine this worst case scenario. Focusing on the qualitative narratives of eight rape survivors who initially disclosed the assault but then stopped disclosing for a significant period of time, this study sought to provide an in‐depth description of how negative reactions silenced these survivors. Three routes to silence were identified: 1) negative reactions from professionals led survivors to question whether future disclosures would be effective; 2) negative reactions from friends and family reinforced feelings of self‐blame; and 3) negative reactions from either source reinforced uncertainty about whether their experiences qualified as rape. Implications for future research and practice are discussed.
A dynamic mass balance model for phosphorus fluxes and concentrations in coastal areas
Authors: Håkanson Lars , Eklund Jenny M.
Published: November 2006

This paper presents a general, process‐based mass balance model (CoastMab) for total phosphorus (TP) in defined coastal areas (at the ecosystem scale). The model is based on ordinary differential equations and calculates inflow, outflow and internal fluxes on a monthly basis. It consists of four compartments: surface water, deep water, erosion/transportation areas for fine sediments and accumulation areas for fine sediments. The separation between surface water and deep water is not done based on water temperature, but on sedimentological criteria instead (from the theoretical wave base). There are algorithms for all major internal TP fluxes (sedimentation, resuspension, diffusion, mixing and burial). Validations were performed using data from 21 different Baltic coastal areas. The results show that the model predicts monthly TP in water and chlorophyll a very well (generally within the uncertainty bands of the empirical data). The model has also been put through sensitivity tests, which show that the most important factor regulating the predictions of the model is generally the TP concentration in the sea beyond the coast. The model is simple to apply, since all driving variables may be accessed from maps or monitoring programs. The driving variables include coastal area, section area (between the defined coastal area and the adjacent sea), mean and maximum depths, latitude (used to predict water temperatures, stratification and mixing), salinity and TP concentration in the sea. Many of the model structures are general and could be used for areas other than those included in this study, e.g., for open coasts, estuaries or tidal coasts, as well as for other substances than phosphorus.
Non‐random structure of a guild of geckos in a fragmented, human‐altered, African rainforest
Authors: Luiselli Luca , Eniang Edem A. , Akani Godfrey C.
Published: November 2006

We examined the guild structure of geckos at a farmbush–rainforest mosaic area in southern Nigeria, during three independent survey periods (i.e. dry season of 1997, 2001, and 2005). We used several simulation descriptors (C value, V ratio, number of checkerboard species pairs, number of species combinations), generated by Monte Carlo methods, to contrast the actual data matrix with the randomly generated data matrix. We calculated the relative availability and use by species of habitat types and microhabitat types at each of these survey periods and also studied temporal niche aspects. We found that our gecko guild was composed of six species, including native forest specialists as well as native habitat generalists and exotic species linked to human‐made habitats. Monte Carlo simulations revealed the occurrence of a structure in the guild under study with regard to habitat type but not with regard to (a) two types of microhabitat uses (i.e. perch height and size of trees) and (b) daily time. The use of simulation analyses also demonstrated that the various species that were similar in terms of habitat use partitioned their microhabitat niche, reducing potential interspecific competition. On the other hand, those species that were clearly separated with regard to habitat type readily frequented the same microhabitats within different habitat types.
Computer-aided design of nano-filter construction using DNA self-assembly
Authors: Mohammadzadegan Reza , Mohabatkar Hassan
Published: November 2006

Computer-aided design plays a fundamental role in both top-down and bottom-up nano-system fabrication. This paper presents a bottom-up nano-filter patterning process based on DNA self-assembly. In this study we designed a new method to construct fully designed nano-filters with the pores between 5 nm and 9 nm in diameter. Our calculations illustrated that by constructing such a nano-filter we would be able to separate many molecules.
Recovery after coronary artery bypass grafting: Patients’ and health professionals’ views of the hospital experience
Authors: Dunckley Maria , Ellard David , Quinn Tom , Barlow Julie
Published: November 2006

Background

Increasing access to revascularisation procedures is a key aspect of a National Service Framework. Coronary artery bypass grafting (CABG) is effective in relieving symptoms and reducing mortality but some patients do not report an improved quality of life or experience a good recovery.

Aims

To describe the recovery trajectory after CABG and identify facilitators and barriers to recovery.

Methods

Semi-structured interviews were conducted with 11 patients who had previously undergone elective, isolated, first-time CABG and with 10 health professionals experienced in caring for these patients.

Results

Thematic analysis identified the following themes: definition and timeline of recovery, preparation for surgery including information provision, attitude to surgery and confidence in staff, clinical factors and the in-patient experience. The key finding is the different recovery trajectory between patients with severe versus mild pre-operative symptoms; patients with few pre-CABG symptoms reported a much longer recovery time.

Conclusions

This study has provided insights into the barriers and facilitators to recovery after CABG and the processes involved. Findings have indicated areas where health professionals can intervene to aid patients’ long-term recovery and thereby maximise the benefits of CABG.
A review of records from follow-up visits for immigrant and Swedish patients at a heart failure clinic
Authors: Hedemalm Azar , Schaufelberger Maria , Ekman Inger
Published: November 2006

Today, nearly 20% of the Swedish population originates from multiethnic backgrounds. Patients’ symptom expressions, adherence to health regimens, and communication with health-care professionals have been shown to be related to their ethnic and cultural backgrounds.

Purpose

To describe documented care of immigrant patients and matched Swedish patients at a heart failure clinic.

Method

Journal audit of records of 25 immigrant and 25 matched Swedish patients with HF included from the patient registration database at the hospital where they were cared for.

Results

In the immigrant group, significantly fewer clinical parameters were assessed during their visits and fewer patients were scheduled for follow-up visits. Analyses revealed that some of the items recommended in the European Society of Cardiology guidelines for non-pharmacological HF care were overlooked for both of the groups.

Conclusions

We found that medication adjustments and information about the condition and treatment were fairly similarly documented between Swedish and immigrant patients while significantly fewer clinical measurements and follow-up visits were documented for the immigrant group.
Identification of p38MAPK‐dependent genes with changed transcript abundance in H2O2‐induced premature senescence of IMR‐90 hTERT human fibroblasts
Authors: Zdanov Stéphanie , Debacq-Chainiaux Florence , Remacle José , Toussaint Olivier
Published: November 2006

Premature senescence of IMR‐90 human diploid fibroblasts expressing telomerase (hTERT) establishes after exposure to an acute sublethal concentration of H2O2. We showed herein that p38MAPK was phosphorylated after exposure of IMR‐90 hTERT cells to H2O2. Selective inhibition of p38MAPK activity attenuated the increase in the proportion of cells positive for senescence associated β‐galactosidase activity. We generated a low density DNA array to study gene expression profiles of 240 senescence‐related genes. Using this array, p38MAPK inhibitor and p38MAPK small interferent RNA, we identified several p38MAPK‐target genes differentially expressed in H2O2‐stressed IMR‐90 hTERT fibroblasts.
Induction of necrotic cell death and mitochondrial permeabilization by heme binding protein 2/SOUL
Authors: Szigeti Andras , Bellyei Szabolcs , Gasz Balazs , Boronkai Arpad , Hocsak Eniko , Minik Orsolya , Bognar Zita , Varbiro Gabor , Sumegi Balazs , Gallyas Ferenc
Published: November 2006

We found that heme‐binding protein 2/SOUL sensitised NIH3T3 cells to cell death induced by A23187 and etoposide, but it did not affect reactive oxygen species formation. In the presence of sub‐threshold calcium, recombinant SOUL provoked mitochondrial permeability transition (mPT) in vitro that was inhibited by cyclosporine A (CsA). This effect was verified in vivo by monitoring the dissipation of mitochondrial membrane potential. Flow cytometry analysis showed that SOUL promoted necrotic death in A23187 and etoposide treated cells, which effect was prevented by CsA. These data suggest that besides its heme‐binding properties SOUL promotes necrotic cell death by inducing mPT.
Characterization of red cell membrane proteins as a function of red cell density:
Authors: Caterino Marianna , Ruoppolo Margherita , Orrù Stefania , Savoia Marcella , Perrotta Silverio , Del Vecchio Luigi , Salvatore Francesco , Stewart Gordon W. , Iolascon Achille
Published: November 2006

Annexin VII was present in reticulocytes but was then lost as the cells matured. A different pattern was found in band 3‐deficient samples: annexin VII was in fact present in both mature and immature red cell membranes. Cytoskeletal anomalies may then influence the turn‐over of annexin VII during erythrocyte maturation.
Urinary tract infections in cats with hyperthyroidism, diabetes mellitus and chronic kidney disease
Authors: Mayer-Roenne Bettina , Goldstein Richard E. , Erb Hollis N.
Published: November 2006

The prevalence of urinary tract infections (UTIs) in cats with hyperthyroidism ( n=90), diabetes mellitus (DM) ( n=57) and chronic kidney disease (CKD) ( n=77) was evaluated retrospectively. It was found to be 12% in cats with hyperthyroidism and DM, respectively, and 22% in cats with CKD. Associations between UTIs and clinical signs, biochemical markers in serum and urinalyses were investigated. Many of the cats with UTIs had no clinical signs of lower urinary tract disease or changes in their laboratory values indicative of infection. Therefore, a urinalysis alone should not be used to exclude UTIs in these cats. UTIs are relatively common in cats with hyperthyroidism, DM and CKD, and urine cultures are recommended as part of the basic diagnostic plan for cats suspected of suffering from these conditions.
Electronic reverse auction configuration and its impact on buyer price and supplier perceptions of opportunism: A laboratory experiment
Authors: Carter Craig R. , Stevens Cynthia Kay
Published: November 2006

Buying organizations are increasingly using electronic reverse auctions (eRAs) to source from suppliers. However, recent quasi‐experimental and field research has suggested that the use of this sourcing technique can create perceptions of opportunism among participating suppliers. Yet from the buyer's perspective, online reverse auctions can yield lower purchase prices. Given the many ways in which to configure on‐line auctions, we extend existing research by using a laboratory experiment to investigate how different reverse auction configurations jointly influence bid price and suppliers’ perceptions of buyer opportunism.

Our findings suggest that supplier bid prices decrease over time as they participate in more eRAs, regardless of the configuration of auction parameters. However, the combination of rank (versus price) visibility, high (versus low) supplier need to win a contract, and six (versus three) competitors was significantly more effective than other combinations of variables in immediately reducing bid prices. The data also indicated that when suppliers’ bids dropped substantially across auctions, their perceptions of opportunism increased. Notably, auction parameter combinations such as price visibility, three competitors, and low need for the contract yielded comparably low bids by the third auction, without any increases in perceived buyer opportunism.
Dung, diet, and the paleoenvironment of the extinct shrub-ox (Euceratherium Collinum) on the Colorado Plateau, USA
Authors: Kropf Manny , Mead Jim I. , Scott Anderson R.
Published: November 2006

Fossil remains of Euceratherium collinum (extinct shrub-ox) have been found throughout North America, including the Grand Canyon. Recent finds from the Escalante River Basin in southern Utah further extend the animal's range into the heart of the Colorado Plateau. E. collinum teeth and a metapodial condyle (foot bone) have been recovered in association with large distinctively shaped dung pellets, a morphology similar to a ‘Hershey's Kiss’ (HK), from a late Pleistocene dung layer in Bechan Cave. HK dung pellets have also been recovered from other alcoves in the Escalante River Basin including Willow and Fortymile canyons. Detailed analyses of the HK pellets confirmed them to be E. collinum and indicate a browser-type diet dominated (> 95%) by trees and shrubs: Artemisia tridentata (big sagebrush), Acacia sp. (acacia), Quercus (oak), and Chrysothamnus (rabbit brush). The retrieval of spring and fall pollen suggests E. collinum was a year-round resident in the Escalante River Basin.
The dynamics of strong turbulence at free surfaces. Part 2. Free-surface boundary conditions
Authors: BROCCHINI M. , PEREGRINE D. H.
Published: November 2006

Strong turbulence at a water–air free surface can lead to splashing and a disconnected
surface as in a breaking wave. Averaging to obtain boundary conditions for such flows
first requires equations of motion for the two-phase region. These are derived using an
integral method, then averaged conservation equations for mass and momentum are
obtained along with an equation for the turbulent kinetic energy in which extra work
terms appear. These extra terms include both the mean pressure and the mean rate
of strain and have similarities to those for a compressible fluid. Boundary conditions
appropriate for use with averaged equations in the body of the water are obtained
by integrating across the two-phase surface layer.

A number of ‘new’ terms arise for which closure expressions must be found for
practical use. Our knowledge of the properties of strong turbulence at a free surface
is insufficient to make such closures. However, preliminary discussions are given for
two simplified cases in order to stimulate further experimental and theoretical studies.

Much of the turbulence in a spilling breaker originates from its foot where turbulent
water meets undisturbed water. A discussion of averaging at the foot of a breaker
gives parameters that may serve to measure the ‘strength’ of a breaker.
Generation of collimated jets by a point source of heat and gravity
Authors: SHTERN VLADIMIR , HUSSAIN FAZLE
Published: November 2006

New solutions of the Boussinesq equations describe the onset of convection as well
as the development of collimated bipolar jets near a point source of both heat
and gravity. Stability, bifurcation, and asymptotic analyses of these solutions reveal
details of jet formation. Convection (with l cells) evolves from the rest state at the
Rayleigh number Ra = Racr = (l − 1)l(l + 1)(l + 2). Bipolar (l = 2) flow emerges
at Ra = 24 via a transcritical bifurcation: Re = 7(24 − Ra)/(6 + 4Pr), where Re is a convection
amplitude (dimensionless velocity on the symmetry axis) and Pr is the
Prandtl number. This flow is unstable for small positive values of Re but becomes
stable as Re exceeds some threshold value. The high-Re stable flow emerges from the
rest state and returns to the rest state via hysteretic transitions with changing Ra.
Stable convection attains high speeds for small Pr (typical of electrically conducting
media, e.g. in cosmic jets). Convection saturates due to negative ‘feedback’: the flow
mixes hot and cold fluids thus decreasing the buoyancy force that drives the flow. This
‘feedback’ weakens with decreasing Pr, resulting in the development of high-speed
convection with a collimated jet on the axis. If swirl is imposed on the equatorial
plane, the jet velocity decreases. With increasing swirl, the jet becomes annular and
then develops flow reversal on the axis. Transforming the stability problem of this
strongly non-parallel flow to ordinary differential equations, we find that the jet is
stable and derive an amplitude equation governing the hysteretic transitions between
steady states. The results obtained are discussed in the context of geophysical and
astrophysical flows.
Vortex core behaviour in confined and unconfined geometries: a quasi-one-dimensional model
Authors: DARMOFAL D. L. , KHAN R. , GREITZER E. M. , TAN C. S.
Published: November 2006

Axisymmetric vortex core flows, in unconfined and confined geometries, are examined
using a quasi-one-dimensional analysis. The goal is to provide a simple unified view of
the topic which gives insight into the key physical features, and the overall parametric
dependence, of the core area evolution due to boundary geometry or far-field pressure
variation. The analysis yields conditions under which waves on vortex cores propagate
only downstream (supercritical flow) or both upstream and downstream (subcritical
flow), delineates the conditions for a Kelvin–Helmholtz instability arising from the
difference in core and outer flow axial velocities, and illustrates the basic mechanism
for suppression of this instability due to the presence of swirl. Analytic solutions
are derived for steady smoothly, varying vortex cores in unconfined geometries
with specified far-field pressure and in confined flows with specified bounding area
variation. For unconfined vortex cores, a maximum far-field pressure rise exists
above which the vortex cannot remain smoothly varying; this coincides with locally
critical conditions (axial velocity equal to wave speed) in terms of wave propagation.
Comparison with axisymmetric Navier–Stokes simulations and experimental results
indicate that this maximum correlates with the appearance of vortex breakdown
and marked core area increase in the simulations and experiments. For confined
flows, the core stagnation pressure defect relative to the outer flow is found to
be the dominant factor in determining conditions for large increases in core size.
Comparisons with axisymmetric Navier–Stokes computations show that the analysis
captures qualitatively, and in many instances, quantitatively, the evolution of vortex
cores in confined geometries. Finally, a strong analogy with quasi-one-dimensional
compressible flow is demonstrated by construction of continuous and discontinuous
flows as a function of imposed downstream core edge pressure.
The transition from inertia- to bottom-drag-dominated motion of turbulent gravity currents
Authors: HOGG ANDREW J. , WOODS ANDREW W.
Published: November 2006

The influence of drag on the motion of gravity currents over rigid horizontal surfaces
is considered analytically using a Chézy model of boundary shear stress. Although
the initial motion is governed by a balance between the buoyancy forces and fluid
inertia, drag gradually influences the flow. The length and time scales at which these
effects become significant are identified. A perturbation series, valid at early times, is
constructed to analyse the changes to the velocity and height of the evolving current
due to drag. At much later times, a new class of similarity solutions is developed
to model the motion which is now governed by a balance between buoyancy and
drag. The transition in the dominant forces which govern the dynamics of the flow
is examined by numerically integrating the equations of motion for flows generated
by a constant flux of relatively dense fluid. The numerical results confirm both the
perturbation solution, valid at early times, and the new similarity solution valid at late
times. The transition between the two may involve the formation of a discontinuity
(bore). Finally particle-driven currents, which exhibit different dynamical behaviour
due to the progressive reduction of their density arising from particle sedimentation,
are investigated.
An improved exact Riemann solver for relativistic hydrodynamics
Authors: REZZOLLA LUCIANO , ZANOTTI OLINDO
Published: November 2006

A Riemann problem with prescribed initial conditions will produce one of three
possible wave patterns corresponding to the propagation of the different
discontinuities that will be produced once the system is allowed to relax. In general, when
solving the Riemann problem numerically, the determination of the specific wave
pattern produced is obtained through some initial guess which can be successively
discarded or improved. We here discuss a new procedure, suitable for implementation
in an exact Riemann solver in one dimension, which removes the initial ambiguity
in the wave pattern. In particular we focus our attention on the relativistic velocity
jump between the two initial states and use this to determine, through some analytic
conditions, the wave pattern produced by the decay of the initial discontinuity. The
exact Riemann problem is then solved by means of calculating the root of a nonlinear
equation. Interestingly, in the case of two rarefaction waves, this root can even be
found analytically. Our procedure is straightforward to implement numerically and
improves the efficiency of numerical codes based on exact Riemann solvers.
Die affektive Einstellungskomponente und ihr Beitrag zur Erklärung von Sportpartizipation
Authors: Brand Ralf
Published: November 2006

Zusammenfassung. Fast alle derzeit diskutierten Modelle zur Erklärung von Gesundheitsverhalten gründen auf einem rational choice-Ansatz und betonen die Bedeutung kognitiver Determinanten im Prozess der Veränderung oder Aufrechterhaltung von Verhalten. In einigen Modellen wird hierzu auch die Einstellung in Rechnung gezogen, die Personen gegenüber der in Frage stehenden Verhaltensweise einnehmen. Die vorliegende Studie repliziert das Kernergebnis einer Untersuchung von Kiviniemi (2004) , die zeigt, dass sich gesundheitsbezogenes Verhalten regressionsanalytisch besser aus der affektiven als aus der kognitiven Einstellungskomponente erklären lässt. Die eigene Untersuchung, bei der 196 Erwachsene im Alter zwischen 40 und 60 Jahren befragt wurden, stützt diesen Befund. Wenn die affektive Einstellungskomponente in ein binär logistisches Regressionsmodell zur Erklärung von Sportpartizipation mit aufgenommen wird, dann reduziert sich der Beitrag der kognitiven Einstellungskomponente auf ein nicht mehr signifikantes Maß. Die Ergebnisse der dargestellten Arbeiten laden dazu ein, in künftigen Untersuchungen neben den bewährten kognitiven Verhaltensdeterminanten, auch die Bedeutung emotionaler Variablen näher zu betrachten.
What Makes a Psychology Graduate Distinctive?
Authors: Hayes Nicky
Published: November 2006

This paper explores the question of what an individual gains from having undertaken and completed an undergraduate (a 3-year bachelor) degree in psychology in the United Kingdom. It addresses the question in two ways. The first is by describing a set of skills and knowledge which an individual can be expected to acquire as a direct result of taking psychology as a subject. These fall into three groups: first, specific skills such as numeracy and literacy; second, knowledge resulting directly from the content of a psychology degree (bearing in mind that these can vary considerably in content and orientation); and third, synthetic skills derived from the epistemological characteristics of psychology as an academic discipline. The paper then goes on to discuss some of the more general outcomes of, or benefits from, the study of psychology. It addresses the question of psychology as a liberal education, and of the internalized and automatized nature of much psychological knowledge, since the latter often acts as a barrier to a full awareness of what an individual has actually gained from their course.
Ecology of Depression in Spanish Children
Authors: Barrio Victoria del , Moreno Carmen , López Rosa
Published: November 2006

The research described here is based on Moos' theoretical framework -(1988), which assumes that events and coping strategies in the lives of individuals depend on personal and social factors operating on these individuals. The present project attempts to clarify: (1) possible relationships between emotional (depressive and anxious) states and specific, recent life events; and (2) the strategies employed by individuals in coping with disturbing life events. The results could serve to orientate preventive intervention in adolescents in order to promote safer problem-solving strategies in young people.
Psychology Teaching in Europe
Authors: Newstead Stephen E. , Makinen Susanna
Published: November 2006

This paper presents an overview of psychology teaching in Europe. A variety of different sources are used, including published articles, a survey, and a sampling of students' opinions. The evidence indicates that there are three main models of training: continuous generic; continuous specialist; and discontinuous specialist, in which students receive a genera1 training for 3 years before specializing. Despite variations in the curriculum taught, the basic areas covered seem to be similar in most countries. Psychology students in Europe are predominantly female. Despite the many differences, it seems that European psychology is less disparate than it first appears, partly because of the Americanization of much European psychology. Psychology can provide a valuable perspective on many of the problems currently besetting Europe, and for this and other reasons the future of psychology appears bright.
Radiation from an electron beam in a magnetized plasma: Whistler mode wave packets
Authors: Brenning N. , Axnäs I. , Raadu M. A. , Tennfors E. , Koepke M.
Published: November 2006

Experimental studies are reported of oscillations and radiation that is spontaneously excited by an electron beam which is shot along a diverging magnetic field into a plasma from a hot cathode. In the present study we focus on oscillations below the electron gyrofrequency, where we find that whistler mode radiation appears in the form of bursts, or wave packets, each with typically 0.1–1 μs time duration, and which together cover typically a few percent of the full time. Wave packets are found in a broad frequency range of 7–40 MHz, while each individual wave packet is dominated by a single frequency. There is propagation along two routes: at the group velocity resonance cone angle, away from the central channel where the waves are excited, and in a channel along the magnetic field. Features of the whistler mode wave packets that are studied include (1) the statistics of amplitudes, frequencies, and time durations; (2) the propagation and decay of wave packets with different frequencies; (3) the group and phase velocities; and (4) how the wave packet production varies with the energy, and the current density, in the electron beam.
Spectral type of auroral precipitating electrons estimated from optical and cosmic noise absorption measurements
Authors: Tanaka Y.‐M. , Kubota M. , Ishii M. , Monzen Y. , Murayama Y. , Mori H. , Lummerzheim D.
Published: November 2006

We estimate the energy spectra of precipitating electrons from optical emissions and cosmic noise absorption (CNA) that were observed with the all‐sky imager (ASI) and the 16 × 16‐element imaging riometer at Poker Flat Research Range (PFRR) (65.11° N, 147.42° W), Alaska. Maxwellian energy parameters (peak energy and total energy flux) are derived from the auroral spectroscopic emissions according to the conventional photometric method. We theoretically estimate CNA from the derived Maxwellian spectra and compare it with the observed CNA. The difference between the estimated CNA and the observed (δCNA) is used as an indicator of the difference in high‐energy electron flux (E > ∼20 keV) between the actual energy distribution and Maxwellian. This analysis is carried out for two substorm events in the evening sector to show the temporal and spatial variations of the energy spectra. Event 1 exhibits two arcs of CNA during the growth phase of the substorm. The results for this event suggest that the energy spectra of the two CNA arcs have different shapes, and this difference is revealed in the precipitating electron flux quasi‐simultaneously measured by NOAA‐17. Event 2 is a typical substorm that consists of growth, expansion, and recovery phases. The δCNA changes throughout the course of the substorm, which can be consistently explained by the energy spectrum variation of the precipitating electrons measured in previous studies. Furthermore, the energy spectra consistent for both optical and CNA data are estimated by assuming a kappa or a Gaussian distribution. This estimation method based on ground observations of the energy spectra has the potential to provide significant information on substorms.
Reversal of magnetic field rotation in the reconnection layer due to shear flow effects
Authors: Sun Xiaoxia , Lin Yu , Wang Xiaogang
Published: November 2006

We investigate the effects of shear flows on the so‐called “component reconnection,” in which the guide field By ≠ 0, by solving a one‐dimensional Riemann problem for magnetopause reconnection using a resistive MHD simulation. Specifically, we consider the existence of a shear flow perpendicular to the antiparallel magnetic field Bz, while a finite shear flow tangential to Bz may also be present. In the cases without a magnetosheath flow and having thus a sheared flow across the reconnection layer, two time‐dependent intermediate shocks TDIS and TDIS′ are present on the magnetosheath side and the magnetospheric side, respectively, and the strength of TDIS is much stronger than that of TDIS′. Nevertheless, the existence of the shear flows modifies the structure and strength of the time‐dependent intermediate shocks significantly. (1) The perpendicular shear flow Vy0 can lead to the reversal of the rotation sense of the tangential magnetic field in time‐dependent intermediate shocks. The critical shear flow speeds, Vc and V′c, for the reversal of field rotations in TDIS and TDIS′, respectively, are calculated. (2) For shear flow speed Vy0 = Vc, the strong TDIS is replaced by a steady intermediate shock (IS), whereas at Vy0 = V′c an Alfvén wave pulse is present in the reconnection layer. (3) The presence of tangential shear flow Vz0 alters not only the strength of TDIS and TDIS′ but also the critical speeds Vc and V′c. The critical shear flow speeds obtained from our simulation are found to agree very well with those from the ideal magnetohydrodynamics (MHD), in which the time‐dependent intermediate shocks are replaced by rotational discontinuities.
Efficient simulation of a space‐time Neyman‐Scott rainfall model
Authors: Leonard M. , Metcalfe A. V. , Lambert M. F.
Published: November 2006

Existing space‐time Neyman‐Scott models characterize rainfall as the arrival of rain cells, clustered in time and independently distributed in space. Each cell is described as a cylinder having a random intensity (height) and random radial coverage. With this formulation it is possible to have cells with centers lying outside of a target simulation region yet having radii large enough to cover points within the region. To avoid significant boundary effects, it is necessary to include these points in the simulation. However, this can introduce inefficiency into the algorithm that is computationally restrictive. To overcome this, an efficient method is derived and demonstrated to improve computational performance.
New diagnostic techniques and technologies at JET (invited)
Authors: Murari A. , Alper B. , Bertalot L. , Brzozowski J. H. , Coad P. , Conroy S. , De La Luna E. , Ericsson G. , Esser H. G. , Hacquin S. , Kaellne J. , Kiptily V. , Lawson K. , O’Mullane M. , Philipps V. , Sharapov S. , Zastrow K.-D. ,   JET-EFDA Contributors
Published: November 2006

The European Fusion Development Agreement’s mission for JET is the development of ITER scenarios exploiting the specific properties of the device. This task requires significant improvements in the measuring techniques. The most innovative diagnostic upgrades are in the fields of edge measurements, detection of fast magnetohydrodynamics modes and “burning plasma” diagnostics. The importance of plasma-wall interactions, and, in particular, the issue of tritium inventory promoted the development of the quartz microbalance, a detector with improved time resolution to measure material redeposition in the remote areas of the inner divertor. Measurement of Alfvén cascades with unprecedented spectral resolution, reaching a toroidal n number of up to 16, was obtained using an O-mode microwave reflectometer as an interferometer. For the diagnosis of the fusion products, a new approach is being developed to measure the He ash based on double charge exchange between thermalized particles and neutrals from JET beams. There have been several upgrades of the neutron diagnostic systems, one of which, the new time of flight neutron spectrometer designed for high counting rates is described.
Design of multichannel laser interferometry for W7-X
Authors: Kornejew P. , Hirsch M. , Bindemann T. , Dinklage A. , Dreier H. , Hartfuß H.-J.
Published: November 2006

An eight channel interferometer is developed for density feedback control and the continuous measurement of electron density profiles in the stellarator W7-X. An additional sightline is launched in the geometry of the Thomson scattering for cross calibration. Due to the W7-X coil geometry access is strongly restricted. This motivates the optimization of the sightline geometry and design studies for supplementary chords. In-vessel retroreflectors will be used and inserted in the first wall elements. To cope with associated mechanical vibrations and thermal drifts during the discharges with envisaged duration of 30min either two-color or second harmonic interferometry techniques must be applied. Optimum wavelengths are found to be about 10 and 5μm. A CO2∕CO interferometer (10μm∕5μm) will be tested and compared with an existing CO2∕HeNe test interferometer. A special difficulty of remotely operated diagnostics is the need of long transmission lines with a path length of about 60m required from the diagnostics location to the torus hall and back. Different arrangements will be compared.
Laser Integration Line target diagnostics first results (invited)
Authors: Le Breton J. P. , Alozy E. , Boutin J. Y. , Duval A. , Gary S. , Gontier D. , Jasmin S. , Naudy M. , Reverdin C. , Rosch R. , Schmitt S. , Soullie G. , Stemmler P. , Villette B. , Wrobel R. , Hulin S. , Meyer C. , Romary P.
Published: November 2006

The Laser Integration Line (LIL) is part of the Laser Megajoule (LMJ) project. The LMJ installation, which is of the National Ignition Facility (NIF) class, will deliver 1.8MJ at 0.35μm wavelength on target with 60 quadruplets of elementary beams. The energy on target of LIL is 30kJ corresponding to one quadruplet, it is housed in a separate building and has its own experimental setup. Target diagnostics have been progressively installed in the LIL target area. Energy and imaging diagnostics as well as the broadband and high resolution spectrometers have been fabricated in the frame of a unique industrial contract. Optical pointers are used to align the diagnostics to the target. The supervisory system controlling the diagnostics configuration and data acquisition is now able to manage cooperative and Commissariat à l’ Energie Atomique (CEA) shots. The calibration data base is accessible from the processing network and will very soon include the characterization of all the streaked, gated, and charge coupled device cameras. Only the Raman-Brillouin backscatter spectrometer still requires some final work and operating tests. The first diagnostics results have been obtained at the end of 2004. A gated soft x-ray imager, the Diagnostic de Mesure X (DMX) broadband spectrometer and a pinhole static imager were used in demonstration experiments. The purpose of the first experiment was to observe the closing of a slit etched in a tantalum oxide foam when irradiated by x-rays. The next diagnostics to be activated were the high resolution spectrometers, the gated x-ray imager, the two mirror x-ray imagers, and the scattered energy diagnostic. This was done during the preparation phase of a campaign realized in collaboration with the French Lasers and Plasmas Institute at the end of 2005 in order to study heat conduction in inertial confinement fusion plasmas. The next diagnostic which is now in preparation is a velocity interferometer system for any reflector. This diagnostic is in its fabrication phase and will be operational for diamond equation of state experiments.
Updated design for a low-noise, wideband transimpedance photodiode amplifier
Authors: Paul S. F. , Marsala R.
Published: November 2006

The high-speed rotation diagnostic developed for Columbia’s HBT-EP tokamak requires a high quantum efficiency, very low drift detector/amplifier combination. An updated version of the circuit developed originally for the beam emission spectroscopy experiment on TFTR is being used. A low dark current (2nA at 15V bias), low input source capacitance (2pF) FFD-040 N-type Si photodiode is operated in photoconductive mode. It has a quantum efficiency of 40% at the 468.6nm (HeII line that is being observed). A low-noise field-effect transistor (InterFET IFN152 with eNa=1.2nV∕√Hz) is used to reduce the noise in the transimpedance preamplifier (A250 AMPTEK op-amp) and a very high speed (unity-gain bandwidth=200MHz) voltage feedback amplifier (LM7171) is used to restore the frequency response up to 100kHz. This type of detector/amplifier is photon-noise limited at this bandwidth for incident light with a power of >∼2nW. The circuit has been optimized using SIMETRIX 4.0 SPICE software and a prototype circuit has been tested successfully. Though photomultipliers and avalanche photodiodes can detect much lower light levels, for light levels >2nW and a 10kHz bandwidth, this detector/amplifier combination is more sensitive because of the absence of excess (internally generated) noise.