bluuebunny/crossref_metadata_2025 huggingface dataset:
Neonatal screening for glutaric aciduria type I: Strategies to proceed
Authors: Lindner M. , Ho S. , Fang‐Hoffmann J. , Hoffmann G. F. , Kölker S.
Published: June 2006

Acute encephalopathic crisis in glutaric aciduria type I results in an unfavourable disease course and poor outcome, dominated by dystonia, feeding problems, seizures and reduced life expectancy. A conditio sine qua non for the prevention of irreversible brain damage is timely diagnosis and start of therapy, i.e. before the onset of neurological disease. As there are no specific clinical signs or symptoms that allow a reliable detection of these patients before the manifestation of encephalopathic crises, neonatal screening programmes for glutaric aciduria type I have been established in some countries using analysis of glutarylcarnitine in dried blood spots by tandem mass spectrometry. This article summarizes recent strategies, pitfalls and shortcomings of mass screening for glutaric aciduria type I, focusing on the relevant risk of missing patients with a mild biochemical phenotype (i.e. low excretors). Furthermore, it evaluates a binary strategy – using glutarylcarnitine as primary variable and glutarylcarnitine/acylcarnitine ratios as secondary variable – to improve the diagnostic sensitivity and specificity of neonatal screening for glutaric aciduria type I. An optimization of diagnostic as well as therapeutic procedures must be achieved before screening for glutaric aciduria type I can be regarded as reliable and beneficial for all patients.
Liver transplantation for inborn errors of liver metabolism
Authors: Sokal Efienne M.
Published: June 2006

Liver transplantation brings complete recovery from end‐stage liver disease, and full correction of liver based inborn errors of metabolism.
The use of amino acid supplements in inherited metabolic disease
Authors: Walter John H. , MacDonald Anita
Published: June 2006

Amino acid supplements are recognized to be essential for the management of a number of inherited metabolic disorders but their use in some other conditions is more controversial.
Clinical approach to treatable inborn metabolic diseases: An introduction
Authors: Saudubray J.‐M. , Sedel F. , Walter J. H.
Published: June 2006

In view of the major improvements in treatment, it has become increasingly important that in order for first‐line physicians not to miss a treatable disorder they should be able initiate a simple method of clinical screening, particularly in the emergency room. We present a simplified classification of treatable inborn errors of metabolism in three groups. Group 1 includes inborn errors of intermediary metabolism that give rise to an acute or chronic intoxication. It encompasses aminoacidopathies, organic acidurias, urea cycle disorders, sugar intolerances, metal disorders and porphyrias. Clinical expression can be acute or systemic or can involve a specific organ, and can strike in the neonatal period or later and intermittently from infancy to late adulthood. Most of these disorders are treatable and require the emergency removal of the toxin by special diets, extracorporeal procedures, cleansing drugs or vitamins. Group 2 includes inborn errors of intermediary metabolism that affect the cytoplasmic and mitochondrial energetic processes. Cytoplasmic defects encompass those affecting glycolysis, glycogenosis, gluconeogenesis, hyperinsulinisms, and creatine and pentose phosphate pathways; the latter are untreatable. Mitochondrial defects include respiratory chain disorders, and Krebs cycle and pyruvate oxidation defects, mostly untreatable, and disorders of fatty acid oxidation and ketone bodies that are treatable. Group 3 involves cellular organelles and includes lysosomal, peroxisomal, glycosylation, and cholesterol synthesis defects. Among these, some lysosomal disorders can be efficiently treated by enzyme replacement or substrate reduction therapies. Physicians can be faced with the possibility of a treatable inborn error in an emergency, either in the neonatal period or late in infancy to adulthood, or as chronic and progressive symptoms – general (failure to thrive), neurological, or specific for various organs or systems. These symptoms are summarized in four tables. In addition, an extensive list of medications used in the treatment of inborn errors is presented.
THE FIELDS OF REAL AND COMPLEX NUMBERS WITH A SMALL MULTIPLICATIVE GROUP
Authors: VAN DEN DRIES LOU , GÜNAYDIN AYHAN
Published: June 2006

We consider the model theory of the real and complex fields with a multiplicative group having the Mann property. Among these groups are the finitely generated multiplicative groups in these fields. As a by-product we obtain some results on groups with the Mann property in rings of Witt vectors and in fields of positive characteristic.k
GUNDY'S DECOMPOSITION FOR NON-COMMUTATIVE MARTINGALES AND APPLICATIONS
Authors: PARCET JAVIER , RANDRIANANTOANINA NARCISSE
Published: June 2006

We provide an analogue of Gundy's decomposition for $L_1$-bounded non-commutative martingales. An important difference from the classical case is that for any $L_1$-bounded non-commutative martingale, the decomposition consists of four martingales. This is strongly related with the row/column nature of non-commutative Hardy spaces of martingales. As applications, we obtain simpler proofs of the weak type $(1,1)$ boundedness for non-commutative martingale transforms and the non-commutative analogue of Burkholder's weak type inequality for square functions. A sequence $(x_n)_{n \ge 1}$ in a normed space $\mathrm{X}$ is called 2-co-lacunary if there exists a bounded linear map from the closed linear span of $(x_n)_{n \ge 1}$ to $l_2$ taking each $x_n$ to the $n$th vector basis of $l_2$. We prove (using our decomposition) that any relatively weakly compact martingale difference sequence in $L_1 (\mathcal{M}, \tau)$ whose sequence of norms is bounded away from zero is 2-co-lacunary, generalizing a result of Aldous and Fremlin to non-commutative $L_1$-spaces.
Regular expression filters for XML
Authors: HOSAYA HARUO
Published: June 2006

XML data are described by types involving regular expressions. This raises the question of what language feature is convenient for manipulating such data. Previously, we have given an answer to this question by proposing regular expression pattern matching. However, since this construct is derived from ML pattern matching, it does not have an iteration functionality in itself, which makes it cumbersome to process data typed by Kleene stars. In this paper, we propose a novel programming feature regular expression filters. This construct extends the previous proposal by permitting pattern clauses to be closed under arbitrary regular expression operators. This yields many convenient programming idioms such as non-uniform processing of sequences and almost-copying of trees. We further develop a type inference mechanism that obtains (1) types for pattern variables that are locally precise with respect to the type of input values and (2) a type for the result of the whole filter expression that is also locally precise with respect to the types of the body expressions. We discuss how our construct is useful in the practice of XML processing and, in particular, how our type inference is crucial for avoiding changes of programs when types of data to be processed evolve frequently.
Practical type inference for arbitrary-rank types
Authors: JONES SIMON PEYTON , VYTINIOTIS DIMITRIOS , WEIRICH STEPHANIE , SHIELDS MARK
Published: June 2006

Haskell's popularity has driven the need for ever more expressive type system features, most of which threaten the decidability and practicality of Damas-Milner type inference. One such feature is the ability to write functions with higher-rank types – that is, functions that take polymorphic functions as their arguments. Complete type inference is known to be undecidable for higher-rank (impredicative) type systems, but in practice programmers are more than willing to add type annotations to guide the type inference engine, and to document their code. However, the choice of just what annotations are required, and what changes are required in the type system and its inference algorithm, has been an ongoing topic of research. We take as our starting point a λ-calculus proposed by Odersky and Läufer. Their system supports arbitrary-rank polymorphism through the exploitation of type annotations on λ-bound arguments and arbitrary sub-terms. Though elegant, and more convenient than some other proposals, Odersky and Läufer's system requires many annotations. We show how to use local type inference (invented by Pierce and Turner) to greatly reduce the annotation burden, to the point where higher-rank types become eminently usable. Higher-rank types have a very modest impact on type inference. We substantiate this claim in a very concrete way, by presenting a complete type-inference engine, written in Haskell, for a traditional Damas-Milner type system, and then showing how to extend it for higher-rank types. We write the type-inference engine using a monadic framework: it turns out to be a particularly compelling example of monads in action. The paper is long, but is strongly tutorial in style. Although we use Haskell as our example source language, and our implementation language, much of our work is directly applicable to any ML-like functional language.
Phantom types and subtyping
Authors: FLUET MATTHEW , PUCELLA RICCARDO
Published: June 2006

We investigate a technique from the literature, called the phantom-types technique, that uses parametric polymorphism, type constraints, and unification of polymorphic types to model a subtyping hierarchy. Hindley-Milner type systems, such as the one found in Standard ML, can be used to enforce the subtyping relation, at least for first-order values. We show that this technique can be used to encode any finite subtyping hierarchy (including hierarchies arising from multiple interface inheritance). We formally demonstrate the suitability of the phantom-types technique for capturing first-order subtyping by exhibiting a type-preserving translation from a simple calculus with bounded polymorphism to a calculus embodying the type system of SML.
Scaling relations in the paleomagnetosphere derived from MHD simulations
Authors: Zieger B. , Vogt J. , Glassmeier K.‐H.
Published: June 2006

On geological timescales the Earth's dipole moment can vary between 0.1 and 2 times the present value. The weakest internal magnetic fields occur during geomagnetic polarity transitions when the Earth's internal dipole field reverses. Theoretically, the size of the paleomagnetosphere is expected to change in the function of the dipole moment according to a power law scaling relation. We carried out a series of numerical magnetohydrodynamic (MHD) simulations of axial dipolar paleomagnetospheres, gradually decreasing the relative dipole moment from 1 to 0.1, in order to test the validity of the theoretical scaling relations for different values of the north‐south interplanetary magnetic field component (IMF Bz). We study the dipole moment dependence of the standoff distance, the flank distances, and the polar cap size, and derive power law scaling relations with significantly differing scaling exponents as compared to the theoretically expected ones. The extent of deviation from the theoretical scaling exponents is controlled by the magnitude of the southward Bz. We quantify the Bz‐dependence of the size of the magnetosphere and validate our results with the Roelof‐Sibeck bivariate function of magnetopause shape obtained from in‐situ satellite measurements for the present‐day magnetosphere. We conclude that the Roelof‐Sibeck function cannot be applied for southward Bz values stronger than 5 nT. A new Bz‐dependent dipole scaling relation is suggested for the magnetospheric scale size. Inserting our corrected scaling relation in the Hill model of magnetosphere‐ionosphere coupling, a better fit can be obtained between simulated and theoretically calculated paleomagnetospheric transpolar potentials.
Antarctic mass rates from GRACE
Authors: Chen J. L. , Wilson C. R. , Blankenship D. D. , Tapley B. D.
Published: June 2006

We estimate mass trends over Antarctica using gravity variations observed by the Gravity Recovery and Climate Experiment (GRACE) satellite mission during its first 3.5 years (April 2002–November 2005). An image of surface mass trends is constructed from 1° × 1° pixels over the entire continent, and shows two prominent features, a region of mass loss along the coast of West Antarctica, and one of accumulation in East Antarctica. After adjusting for bias due to smoothing and to GRACE's limited spatial resolution, and removing post glacial rebound (PGR) effects, the rate in West Antarctica is −77 ± 14 km3/year, similar to a recent estimate of ice mass loss from satellite altimetry and remote sensing data. The prominent East Antarctic feature in the Enderby Land region has a rate of +80 ± 16 km3/year. Published snow/ice mass rates from remote sensing measurements indicate approximate ice mass balance in this region, suggesting that this feature is either from unquantified snow accumulation in this region or more likely due to unmodeled PGR.
Multireference configuration interaction calculations for the F(P2)+HCl→HF+Cl(P2) reaction: A correlation scaled ground state (1A′2) potential energy surface
Authors: Deskevich Michael P. , Hayes Michael Y. , Takahashi Kaito , Skodje Rex T. , Nesbitt David J.
Published: June 2006

This paper presents a new ground state (1A′2) electronic potential energy surface for the F(P2)+HCl→HF+Cl(P2) reaction. The ab initio calculations are done at the multireference configuration interaction+Davidson correction (MRCI+Q) level of theory by complete basis set extrapolation of the aug-cc-pVnZ (n=2,3,4) energies. Due to low-lying charge transfer states in the transition state region, the molecular orbitals are obtained by six-state dynamically weighted multichannel self-consistent field methods. Additional perturbative refinement of the energies is achieved by implementing simple one-parameter correlation energy scaling to reproduce the experimental exothermicity (ΔE=−33.06kcal∕mol) for the reaction. Ab initio points are fitted to an analytical function based on sum of two- and three-body contributions, yielding a rms deviation of <0.3kcal∕mol for all geometries below 10kcal∕mol above the barrier. Of particular relevance to nonadiabatic dynamics, the calculations show significant multireference character in the transition state region, which is located 3.8kcal∕mol with respect to F+HCl reactants and features a strongly bent F–H–Cl transition state geometry (θ≈123.5°). Finally, the surface also exhibits two conical intersection seams that are energetically accessible at low collision energies. These seams arise naturally from allowed crossings in the C∞v linear configuration that become avoided in Cs bent configurations of both the reactant and product, and should be a hallmark of all X–H–Y atom transfer reaction dynamics between (P2) halogen atoms.
Effects of Zr doping on stoichiometric and reduced ceria: A first-principles study
Authors: Yang Zongxian , Woo Tom K. , Hermansson Kersti
Published: June 2006

The Zr doping in CeO2 may change the reduction properties and therefore the redox properties of CeO2. Using first-principles density functional theory with the inclusion of on-site Coulomb interaction for a 96-atom supercell, these effects are studied by comparing the differences in atomic structures, electronic structures, and reduction energies of the doped CeO2 and those of the nondoped CeO2. It is found that (1) Zr doping of the ceria structure results in important modifications involving nonequivalent O atoms; (2) the oxygen anions (still four-coordinated) next to the doping center show considerably lower reduction energies (by 0.6eV) and larger displacements (“higher mobilities”); (3) an O vacancy is most easily created close to the Zr centers, therefore the Zr-doping centers might serve as nucleation centers for vacancy clustering; and (4) the electrons left by the released oxygen localize on two Ce cations neighboring the vacancy, which results in the reduction of two Ce4+ ions.
Near-infrared two-photon absorption in phthalocyanines: Enhancement of lowest gerade-gerade transition by symmetrical electron-accepting substitution
Authors: Drobizhev M. , Makarov N. S. , Stepanenko Y. , Rebane A.
Published: June 2006

This paper presents, to the best of our knowledge, the first study of two-photon absorption (2PA) spectra of a number of symmetrically substituted phthalocyanines in the excitation wavelength region from λex=800to1600nm. The selected molecules vary by position of substitution (α or β), number of substituent groups (4, 8, or 16), and presence or absence of metal (Zn or Al) in the center. For all phthalocyanines we find a moderately strong (σ2∼100–200GM), pure electronic, gerade-gerade (g-g) 2PA transition, which shows up as a well-resolved relatively narrow peak in the energy region between Q and B bands (λex=870–1100nm). In metallophthalocyanines (MPcs) this lowest g-g transition is followed by the onset of other higher-frequency 2PA transitions. In some metal-free phthalocyanines (H2Pcs) we also reveal a second, broader 2PA transition at slightly higher frequency. In both MPcs and H2Pcs, we find a strong monotonic increase of integrated strength of the lowest g-g transition as a function of electron-accepting ability of peripheral substituents, expressed as their aggregated Hammett constant. By using few essential states models (three states for MPcs and four states for H2Pcs) we demonstrate the primary role of excited-state transition dipole moment in this effect.
A model for ablated-plasma distribution and width for wire-array Z-pinch implosions
Authors: Waisman Eduardo M. , Cuneo M. E. , Stygar W. A. , Sasorov P. V. , Yu E. P.
Published: June 2006

A one-dimensional radial magnetohydrodynamic model of the plasma ablated from a multi-MA wire-array Z pinch is developed. The model is used to compute the mass weighted-density width δ of the plasma at the end of the ablation phase. The wire-array cores are represented as a prescribed source of plasma injection. The plasma, beyond a thin boundary layer, is approximated as a perfect conductor experiencing only magnetic forces and negligible pressure gradients. Assuming that the current driving the Z-pinch implosion increases linearly with time t during the ablation phase, and that the mass-ablation rate varies as tν, it is shown that the density width δ is a function of the dimensionless parameter λ=ua(ta)ta∕r0, where ua is the ablation velocity, ta is the total ablation time, and r0 is the initial wire-array radius. The velocity ua is defined such that its product with the mass-ablation rate equals the magnetic force at r0, which is assumed to be the mass injection point. A solution is obtained for the plasma flow in semianalytical form when the current is an exponential function of time, and ua is constant. The ablated plasma density width δ obtained under these two sets of conditions is compared. In addition, assuming that the plasma sheath at stagnation is proportional to the width δ, scaling relationships for the peak x-ray power radiated when the pinch stagnates on axis are suggested.
Asymptotic iteration method solutions to the relativistic Duffin-Kemmer-Petiau equation
Authors: Boztosun I. , Karakoc M. , Yasuk F. , Durmus A.
Published: June 2006

A simple exact analytical solution of the relativistic Duffin-Kemmer-Petiau equation within the framework of the asymptotic iteration method is presented. Exact bound state energy eigenvalues and corresponding eigenfunctions are determined for the relativistic harmonic oscillator as well as the Coulomb potentials. As a nontrivial example, the anharmonic oscillator is solved and the energy eigenvalues are obtained within the perturbation theory using the asymptotic iteration method.
Novel fiber-based integrating sphere for luminous flux measurements
Authors: Szylowski Martin , Mossman Michele , Barclay David , Whitehead Lorne
Published: June 2006

Traditional integrating spheres, which use a single detector to measure luminous flux, have a number of drawbacks associated with the sources of error caused by baffling, nonideal topology, and variations in surface reflectance. In this article we address the potential drawbacks of many traditional integrating spheres and present a new instrument which achieves accurate measurements without the use of baffles, by relying on optical fibers to distribute measurement points around the interior of a highly reflective structure.
Non-Laplacian growth, algebraic domains, and finite reflection groups
Authors: Loutsenko Igor , Yermolayeva Oksana
Published: June 2006

Dynamics of planar domains with moving boundaries driven by the gradient of a scalar field that satisfies an elliptic PDE is studied. We consider the question: For which kind of PDEs are the domains algebraic, provided the field has singularities at a fixed point inside the domain? The construction reveals a direct connection with the theory of the Calogero-Moser systems related to finite reflection groups and their integrable deformations.
Block-diagonalizability problem for hydrodynamic type systems
Authors: Bogoyavlenskij Oleg I.
Published: June 2006

The necessary and sufficient conditions are derived for the reducibility of a hydrodynamic type system into a block-diagonal form with k mutually interacting blocks. Applications to the perturbations of the Benney system and to the Hamiltonian systems of partial differential equations are presented. The algebraic identities connecting the Nijenhuis tensors NB(A)(u,v) and NA(u,v) and Haantjes tensors HB(A)(u,v) and HA(u,v) are discovered.
Transition scale at quasiperpendicular collisionless shocks: Full particle electromagnetic simulations
Authors: Scholer Manfred , Burgess David
Published: June 2006

One-dimensional full particle simulations of almost perpendicular supercritical collisionless shocks over a wide Alfvén Mach number range are presented. The physical ion to electron mass ratio has been used; however, due to computer time limitations a value of the ratio of the electron plasma frequency to the electron gyrofrequency of 4 has been assumed. The shock structure in the density and magnetic field consists of a foot, formed by reflected ions, and a steeper ramp leading to an overshoot. It is shown that the shock ramp scale in units of the upstream ion inertial length is more or less constant and close to 1 over the Mach number regime investigated, i.e., up to MA≈14. Further, the convective ion gyroradius in units of the upstream ion inertial length is also constant with the Mach number when the gyroradius is evaluated with the magnetic field strength in the overshoot. Thus the shock transition also scales with the convected gyroradius. When a hyperbolic tangent function is fitted to the density profile the neglect of the overshoot essentially results, for high Mach number shocks, in a fit of the foot and not of the ramp, i.e., the shock transition scale is grossly overestimated. The simulations suggest that in a regime above the critical Mach number the nonlinear steepening is balanced by gyroviscosity of the reflected ions as the shock ramp scale is given by the convected gyroradius in the overshoot. At higher Mach numbers the shock becomes unsteady the ramp scale can become as small as several electron inertial length during a part of the reformation cycle. At still higher Mach number microinstabilities in the foot may have growth times much shorter than the inverse ion gyrofrequency so that they can lead to ion heating, and a steady resistive shock will result.
Theoretical transition probabilities for the ÃΠ1-X̃Σ+1 system of AlNC and AlCN isomers based on global potential energy surfaces
Authors: Tokue Ikuo , Nanbu Shinkoh
Published: June 2006

Transition probabilities were evaluated for the X̃Σ+1-ÃΠ1 system of AlNC and AlCN isomers to analyze photoabsorption and fluorescence spectra. The global potential energy surfaces (PESs) of the X̃Σ+1 and ÃΠ1 (1A″1,2A′1) electronic states were determined by the multireference configuration interaction calculations with the Davidson correction. Einstein’s B coefficients were computed by quantum vibrational calculations using the three-dimensional PESs of these states and the electronic transition moments for the X̃-1A″1 and X̃-2A′1 systems. Einstein’s B coefficients obtained for AlNC or AlCN exhibit that the Al–N or Al–C stretching mode is strongly enhanced in the transition. The absorption and fluorescence spectra calculated for the X̃-1A″1 and X̃-2A′1 systems are discussed comparing with the observed photoexcitation and fluorescence spectra. The lifetimes for the several vibrational levels of the ÃΠ1 state were calculated to be ca. 7ns for AlNC and 21–24ns for AlCN from the fluorescence decay rates of the 1A″1-X̃ and 2A′1-X̃ emissions.
Noncontinuum effects in nanoparticle dynamics in polymers
Authors: Ganesan Venkat , Pryamitsyn Victor , Surve Megha , Narayanan Bharadwaj
Published: June 2006

We propose a continuum model for the dynamics of particles in polymer matrices which encompasses arbitrary size ratios of the polymer and particle. We present analytical and computer simulation results for the mobility of the particles and the viscosity of the suspension for the case of unentangled polymer melts. Our results indicate strong dependencies of the particle mobility upon the polymer-particle size ratios and much reduced intrinsic viscosities for the suspensions. These predictions rationalize some recent experimental observations on the dynamics of nanoparticles in polymer melts.
Venular basement membranes contain specific matrix protein low expression regions that act as exit points for emigrating neutrophils
Authors: Wang Shijun , Voisin Mathieu-Benoit , Larbi Karen Y. , Dangerfield John , Scheiermann Christoph , Tran Maxine , Maxwell Patrick H. , Sorokin Lydia , Nourshargh Sussan
Published: June 2006

The mechanism of leukocyte migration through venular walls in vivo is largely unknown. By using immunofluorescence staining and confocal microscopy, the present study demonstrates the existence of regions within the walls of unstimulated murine cremasteric venules where expression of key vascular basement membrane (BM) constituents, laminin 10, collagen IV, and nidogen-2 (but not perlecan) are considerably lower (<60%) than the average expression detected in the same vessel. These sites were closely associated with gaps between pericytes and were preferentially used by migrating neutrophils during their passage through cytokine-stimulated venules. Although neutrophil transmigration did not alter the number/unit area of extracellular matrix protein low expression sites, the size of these regions was enlarged and their protein content was reduced in interleukin-1β–stimulated venules. These effects were entirely dependent on the presence of neutrophils and appeared to involve neutrophil-derived serine proteases. Furthermore, evidence was obtained indicating that transmigrating neutrophils carry laminins on their cell surface in vivo. Collectively, through identification of regions of low extracellular matrix protein localization that define the preferred route for transmigrating neutrophils, we have identified a plausible mechanism by which neutrophils penetrate the vascular BM without causing a gross disruption to its intricate structure.
Variability in growth of longfinned eels among coastal catchments of south‐eastern Australia
Authors: Walsh C. T. , Pease B. C. , Hoyle S. D. , Booth D. J.
Published: June 2006

Longfinned eels Anguilla reinhardtii were captured by both fishery‐dependent and independent sampling methods from three rivers in New South Wales, south‐eastern Australia. Growth rates were examined in two zones (fresh water and tidal) in the Hacking, Hawkesbury and Clarence Rivers. Mean annual growth increments of sampled longfinned eels ranged from 30 to 60 mm year−1 using age‐length analyses and up to 167 mm year−1 based on tag‐recapture model estimates (GROTAG), with both methods showing high intra‐ and inter‐population variability. Growth was significantly faster in younger (5–15 years) fish than older (>15 years) fish, with females growing an average 10 mm year−1 faster than males of similar age and capture location. Longfinned eels found in tidal areas grew significantly faster than those in non‐tidal freshwater areas as a result of longer growing seasons in the highly productive estuarine habitats. Other possible factors influencing variability in growth rates for this species include habitat preference, density and fishing pressure.
Diverse migratory histories of Japanese Trachidermus and Cottus species (Cottidae) as inferred from otolith microchemistry
Authors: Goto A. , Arai T.
Published: June 2006

The migratory histories of Japanese freshwater sculpins, one Trachidermus and four Cottus species, were studied by examining strontium (Sr) and calcium (Ca) concentrations in their otoliths using wavelength dispersive X‐ray spectrometry on an electron microprobe. The Sr : Ca ratios in the otoliths changed with salinity of the habitat. The otoliths of Cottus nozawae showed consistently low Sr : Ca ratios, with an average of 3·37 × 10−3 from the core to the edge, suggesting a freshwater resident life cycle. In contrast, the otolith Sr : Ca ratios for Trachidermus fasciatus and Cottus kazika changed along the life history transects possibly in accordance with their migration patterns from sea to fresh water. The ratios of T. fasciatus and C. kazika averaged 5·4 × 10−3 and 5·3 × 10−3 respectively, in the otolith region from the core to the points 450–890 μm, and changed to the lower levels, averaging 2·0 × 10−3 and 2·7 × 10−3, in the outer otolith region. These data suggest that both the species have a catadromous life cycle. The otoliths of Cottus hangiongensis had low Sr : Ca ratios in the two regions from the core to the points 15–30 μm and the points 415–582 μm to the edge, averaging 2·0 × 10−3 and 1·9 × 10−3, with significantly higher ratios in the narrow area between these regions, averaging 4·6 × 10−3. Similar ontogenetic changes in otolith Sr : Ca ratios were found in the otoliths of Cottus amblystomopsis, suggesting their amphidromous life cycle. These findings suggest that otolith Sr : Ca ratios reflect individual life histories and that Japanese Trachidermus and Cottus species have diverse migratory histories.
The Cognitive Neuroscience of Aging and Culture
Authors: Park Denise , Gutchess Angela
Published: June 2006

Research into the cognitive neuroscience of aging has revealed exciting and unexpected changes to the brain over the lifespan. However, studies have mostly been conducted on Western populations, raising doubts about the universality of age-related changes. Cross-cultural investigation of aging provides a window into the stability of changes with age due to neurobiology, as well as into the flexibility of aging due to life experiences that impact cognition. Behavioral findings suggest that different cultures process distinct aspects of information and employ diverse information-processing strategies. The study of aging allows us to identify those age-related neural changes that persist across cultures as well as the changes that are driven by culture-specific life experiences.
A Brain-Based Account of the Development of Rule Use in Childhood
Authors: Bunge Silvia A. , Zelazo Philip David
Published: June 2006

The ability to follow explicit rules improves dramatically during the course of childhood, but relatively little is known about the changes in brain structure and function that underlie this behavioral improvement. Drawing from neuroscientific studies in human adults and other animals, as well as from an emerging literature in developmental cognitive neuroscience, we propose a brain-based account of the development of rule use in childhood. This account focuses on four types of rules represented in different parts of the prefrontal cortex: simple rules for reversing stimulus–reward associations, pairs of conditional stimulus–response rules (both univalent and bivalent), and higher-order stimulus–response rules for selecting among task sets. It is hypothesized that the pattern of developmental changes in rule use reflects the different rates of development of specific regions within the prefrontal cortex.
Positive Affect and Health
Authors: Cohen Sheldon , Pressman Sarah D.
Published: June 2006

Negative affective styles such as anxiety, depression, and hostility have long been accepted as predictors of increased risk for illness and mortality. In contrast, positive affective styles have been relatively ignored in the health literature. Here we highlight consistent patterns of research associating trait positive affect (PA) and physical health. The evidence we review suggests an association of trait PA and lower morbidity and decreased symptoms and pain. PA is also associated with increased longevity among community-dwelling elderly. The association of PA and survival among those with serious illness is less clear and suggests the possibility that PA may be harmful in some situations. We conclude by raising conceptual and methodological reservations about this literature and suggesting directions for future research.
Distance Perception
Authors: Proffitt Dennis R.
Published: June 2006

Distance perception seems to be an incredible achievement if it is construed as being based solely on static retinal images. Information provided by such images is sparse at best. On the other hand, when the perceptual context is taken to be one in which people are acting in natural environments, the informational bases for distance perception become abundant. There are, however, surprising consequences of studying people in action. Nonvisual factors, such as people's goals and physiological states, also influence their distance perceptions. Although the informational specification of distance becomes redundant when people are active, paradoxically, many distance-related actions sidestep the need to perceive distance at all.
Brain Mechanisms for Interpreting the Actions of Others From Biological-Motion Cues
Authors: Pelphrey Kevin A. , Morris James P.
Published: June 2006

Humans are an intensely social species. Our social abilities depend upon specialized brain systems for rapidly recognizing the faces of others, for interpreting the actions of others through an analysis of biological-motion cues, and for determining the emotional states of others via inspection of facial expression. Recent work has implicated the superior temporal sulcus (STS) region as an important component of the social brain. Functional neuroimaging studies have provided clues about how this region is involved in the visual analysis and interpretation of other people's actions. STS activity is modulated by the context within which the actions of biological entities are observed. Such a contextual influence is consistent with a broader tradition within social psychology emphasizing the powerful influences of situational and contextual factors on behavior and perception. The STS region also shows promise as a region of importance in the investigation of both typical and impaired social-cognitive development. Future work should aim to inform us better of the development of interrelationships between the STS region and other regions of the social brain, including the amygdala and the fusiform gyrus.
Evaluating Explanations in Law, Science, and Everyday Life
Authors: Thagard Paul
Published: June 2006

This article reviews a theory of explanatory coherence that provides a psychologically plausible account of how people evaluate competing explanations. The theory is implemented in a computational model that uses simple artificial neural networks to simulate many important cases of scientific and legal reasoning. Current research directions include extensions to emotional thinking and implementation in more biologically realistic neural networks.
Diversity, abundance and depth distribution of demersal deep‐water fishes off Lanzarote and Fuerteventura, Canary Islands
Authors: Uiblein F. , Bordes F. , Castillo R.
Published: June 2006

A total of 168 bottom longline operations were carried out at depths between 72 and 1102 m during four cruises off Lanzarote and Fuerteventura, Canary Islands. One hundred and twenty‐eight operations were successful, resulting in the capture of 1167 fishes belonging to 55 species. Clear variations in fish total weight and number, species richness and diversity, and the relative abundance of single species occurred among five different depth zones between 100 and 1100 m. The particular platform topography of the Canary Islands may affect the density and diversity of slope‐dwelling fishes. Whereas fish body length and weight showed an overall increase with depth, no such trends were found at the level of individual species. One species, Lepidopus caudalus, even revealed a bigger‐shallower trend. Among three species of trichiurids, depth distribution patterns were detected that may reflect vertical space partitioning. In October 1995, an unusually high number of Mora moro with advanced gonadal maturity were collected off eastern Fuerteventura at 997 m depth. At lesser depths and during other seasons, only a few individuals of this species were caught in the same area. This indicated a seasonal variability in local abundance that is most probably related to reproduction. Mora moro has an excellent flesh and may represent a valuable fisheries resource. Open problems requiring further research in the study area such as selectivity effects of the fishing gear and possible influences of ecological factors on geographical distribution of the deep‐water ichthyofauna, as well as important aspects of the future demersal fisheries management in the Canarian archipelago are briefly outlined.
The deep scattering layers in the Irminger Sea
Authors: Magnússon J.
Published: June 2006

Continuous deep‐scattering layers have been observed in the Irminger Sea for many years. Acoustic observations were carried out during the O‐group surveys in the Irminger Sea, in August, in the years 1993–1995. In this paper, the distribution and relative abundance of component organisms based on acoustic values is presented. The layers are observed within the range of 400‐500 m to 700‐800 m depth. Diurnal migrations of a part of the layers are described. The layers consist of a great variety of organisms. The known components are mainly diverse species offish of which an overview is given. Regional differences are outlined.
Estimation of abundance of abyssal demersal fishes; a comparison of data from trawls and baited cameras
Authors: Priede I. G. , Merrett N. R.
Published: June 2006

The abundance of the macrourid Coryphaenoides (Nematonurus) armatus was investigated using a single warp trawl and baited camera at soundings from 2500 to 5000 m in the north‐east Atlantic Ocean. There was no significant relationship between abundance (n km−2) as determined from swept area of the trawl and numbers of fish photographed at standard baits. However, timing of the first arrival (tarr s) of the first fish at bait correlated well with the trawl data through the relationship:

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It is concluded that by measurement of arrival times, the baited camera provides a cost‐effective complement to trawl sampling for estimating abundance of deep‐water fish including Synaphobranchus kaupi, Anlimora rostratu and C. (N). armatus. However, some abundant species such as the roundnose grenadier Coryphaenoides rupestris were not attracted to baited long‐lines or baited cameras and therefore could be sampled only by trawl.
Reproduction of macrourids in the upper slope of the north‐western Ionian Sea
Authors: D'Onghia G. , Tursi A. , Basanisi M.
Published: June 2006

Aspects of reproduction of macrourid fish in the north‐western Ionian Sea are reported. Data were collected during 12 trawl surveys carried out between 1993 and 1995. Mature and running ripe females of Coelorhynchus coelorhynchus, Hymenocephalus italiens and Nezumia sclerorhynchus were found all year round. Mature females of Trachyrhynchus trachyrhynchus were found mainly in August.
The effect of growth‐dependent mortality, external environment and internal dynamics on larval fish otolith growth: an individual‐based modelling approach
Authors: Gallego A. , Heath M.
Published: June 2006

The daily otolith increment growth of individuals in a cohort of fish larvae was simulated by a simple individual‐based model over 30 days. The daily otolith growth of an individual larva was dependent on past growth, within fixed limits common to all larvae. The survival of a larva at the end of each day was either a linear function of larval growth or a random outcome, simulating growth‐dependent and growth‐independent mortality, respectively, The combined effect of the external environment on growth was also studied. Eleven environmental scenarios, favouring or hindering growth at different stages, were tested and compared to runs with no environmental effect on growth. Growth‐dependent mortality induced an increase in the average otolith daily increment width amongst surviving larvae. Such an outcome, however, could be negated by an unfavourable environment. The increase in mean growth rate of the population generated by growth‐dependent mortality was directly related to the inherent variability in daily otolith growth. With increased variability, the influence of the environment became relatively less important. The effect of the environment on growth was more critical during the early stages of development. A comparison of results generated by the model with patterns observed in data from a field survey of larval herring was consistent with the occurrence of growth‐dependent mortality in the sea. The simulation model provided a useful insight into the way in which various processes controlling larval growth interact.
The role of larval retention and transport features in mortality and potential gene flow of walleye pollock
Authors: Bailey K. M. , Stabeno P. J. , Powers D. A.
Published: June 2006

This paper reviews the physical oceanography in the range of walleye pollock that influences transport and mortality of eggs and larvae, and summarizes the current status of stock structure studies of pollock. A synthesis is presented that links the genetic stock structure and the potential for gene flow due to transport. In the eastern North Pacific Ocean, walleye pollock Theragra chalcogramma consistently spawn in several locations, with the major deposition of planktonic eggs in Shelikof Strait in the Gulf of Alaska and in the eastern Bering Sea, near Unimak Pass. In the Gulf of Alaska, eddies are common features where pollock larvae tend to be concentrated; eddies in the region of Shelikof Strait retain larvae in the region, where they are protected from transport offshore in the Alaska Coastal Current (ACC). The ACC is vigorous in Shelikof Strait (20–50 cm s−1), but in the downstream region along the Alaska Peninsula it flows over the continental shelf and is more sluggish (10 cm s−1). There is equivocal information on the condition and mortality of larvae inside and outside eddies; there may be seasonal and interannual differences in the direct role of eddies on larval mortality. In some years with extremely high storm activity, resulting in a very energetic ACC, eddies are less prevalent and pollock larvae are swept offshore into the swift flowing Alaskan Stream (50–100 cm s−1). In the Alaskan Stream the nutritional condition and growth of larvae is poor, leading to high mortality. Satellite‐tracked drifter trajectories indicate that Alaskan Stream water can enter the Bering Sea through deep Aleutian passes, the nearest (easternmost) being Amutka Pass. Larvae surviving in the Alaskan Stream and carried into the Bering Sea through Amutka Pass would find themselves in the Aleutian Basin, where feeding conditions are poor and where larval mortality has been high. Therefore, geographical barriers (such as the Alaska Peninsula and shallow sills at passes between the Gulf of Alaska and Bering Sea), retention features, and high mortality rates of vagrants are likely to impede gene flow due to larval drift between the Gulf of Alaska and eastern Bering Sea. Recent findings using restriction fragment length polymorphism (RFLP) analysis of mtDNA variation, further supported by differences in nuclear DNA microsatellite loci, indicate distinct genetic stocks in the Bering Sea and Gulf of Alaska. Within the Bering Sea, several geographically separate pollock spawning grounds result in larvae occupying a variety of basin, slope and shelf habitats. Larvae can be concentrated in eddies in slope waters, but on the eastern Bering Sea shelf eddies are uncommon and a persistent mean northwestward flow exists along the 100‐m isobath. Thus, the potential for gene flow through larval drift is much higher. Genetically distinct stocks have not been identified in the eastern Bering Sea, although there is some evidence for their existence.
Estimates of larval survival of cod by releases of genetically marked yolk‐sac larvae
Authors: Kristiansen T. S. , Jørstad K. E. , Otterå H. , Paulsen O. I. , Svåsand T.
Published: June 2006

In the spring of 1995, 18 million genetically marked yolk‐sac cod larvae Gadus morhua were released into a 2.9‐km2, nearly land‐locked fjord in western Norway. Four quantitative surveys were conducted, 11, 33, and 63 days, and 1 year after the first release. Almost 100% of the collected cod larvae were successfully identified to GPI‐1* genotype. The marked cod larvae constituted 18% of all sampled cod larvae in the first survey and 9% in the two next. The average rate of mortality was estimated to be 23% day −1 for the first 10 days after release and 12% day −1 during the next month after release. After 1 year (April 1996), the number genetically marked I‐group cod in the fjord was estimated to be <120. The effect of the historical programme of large‐scale releases of yolk‐sac larvae on recruitment were evaluated and found to be small.
Key Worker Services for Disabled Children: the Views of Parents
Authors: Greco Veronica , Sloper Patricia , Webb Rosemary , Beecham Jennifer
Published: June 2006

This study reports the findings from 68 interviews with parents of disabled children who are users of seven key worker schemes in England and Wales. The interviews which lasted for one hour each, were tape‐recorded, transcribed and analysed according to both a priori and emerging themes. The findings from this study have implications for policy and practice, for example, the necessity of protected time for key workers, the necessity of conveying clear information about the key worker's role, the importance of access to training and information for the key worker, the need for key workers to be proactive, and for their involvement in care plan and review meetings. Copyright © 2006 The Author(s). Journal compilation © 2006 National Children's Bureau
THE EFFECT OF THE REPLACEMENT OF FREE SILICA BY ALUMINA AND ZIRCONIA IN ELECTRICAL PORCELAIN1
Authors: Twells Robert , Lin C. C.
Published: June 2006

Effect on electrical porcelain of the replacement of free silica by alumina and zirconia.—Since it had been suggested that free silica may be detrimental to the mechanical and the dielectric strengths of electrical porcelain, a series of sixteen batches was prepared in which various proportions of the free silica were replaced, weight for weight, by alumina, zirconia or combinations of both, and bars and disks, after burning at cone 8 l/2 to 9 or at cone 12, were tested for shrinkage, transverse strength, impact strength, heat resistance, absorption of moisture and dye penetration. The results show that resistance to sudden temperature changes can be greatly improved by substituting zirconia,—that the danger of overburning can be greatly decreased by substituting alumina and that the mechanical strengths can be increased by substituting either or both; but in the case of dielectric strength, no improvement was obtained by substituting for the free silica.