bluuebunny/crossref_metadata_2025 huggingface dataset:
Reconstructing Distances among Objects from their Discriminability
Authors: Dzhafarov Ehtibar N. , Colonius Hans
Published: April 2006

We describe a principled way of imposing a metric representing dissimilarities on any discrete set of stimuli (symbols, handwritings, consumer products, X-ray films, etc.), given the probabilities with which they are discriminated from each other by a perceiving system, such as an organism, person, group of experts, neuronal structure, technical device, or even an abstract computational algorithm. In this procedure one does not have to assume that discrimination probabilities are monotonically related to distances, or that the distances belong to a predefined class of metrics, such as Minkowski. Discrimination probabilities do not have to be symmetric, the probability of discriminating an object from itself need not be a constant, and discrimination probabilities are allowed to be 0’s and 1’s. The only requirement that has to be satisfied is Regular Minimality, a principle we consider the defining property of discrimination: for ordered stimulus pairs (a, b), b is least frequently discriminated from a if and only if a is least frequently discriminated from b. Regular Minimality generalizes one of the weak consequences of the assumption that discrimination probabilities are monotonically related to distances: the probability of discriminating a from a should be less than that of discriminating a from any other object. This special form of Regular Minimality also underlies such traditional analyses of discrimination probabilities as Multidimensional Scaling and Cluster Analysis.
Rotation to Simple Loadings Using Component Loss Functions: The Oblique Case
Authors: Jennrich Robert I.
Published: April 2006

Component loss functions (CLFs) similar to those used in orthogonal rotation are introduced to define criteria for oblique rotation in factor analysis. It is shown how the shape of the CLF affects the performance of the criterion it defines. For example, it is shown that monotone concave CLFs give criteria that are minimized by loadings with perfect simple structure when such loadings exist. Moreover, if the CLFs are strictly concave, minimizing must produce perfect simple structure whenever it exists. Examples show that methods defined by concave CLFs perform well much more generally. While it appears important to use a concave CLF, the specific CLF used is less important. For example, the very simple linear CLF gives a rotation method that can easily outperform the most popular oblique rotation methods promax and quartimin and is competitive with the more complex simplimax and geomin methods.
The Rigid Orthogonal Procrustes Rotation Problem
Authors: ten Berge Jos M. F.
Published: April 2006

The problem of rotating a matrix orthogonally to a best least squares fit with another matrix of the same order has a closed-form solution based on a singular value decomposition. The optimal rotation matrix is not necessarily rigid, but may also involve a reflection. In some applications, only rigid rotations are permitted. Gower (1976) has proposed a method for suppressing reflections in cases where that is necessary. This paper proves that Gower’s solution does indeed give the best least squares fit over rigid rotation when the unconstrained solution is not rigid. Also, special cases that have multiple solutions are discussed.
THE VILLAGE AS TERRITORY: ENCLOSING LOCALITY IN NORTHWEST ZAMBIA, 1950S TO 1990S
Authors: VON OPPEN ACHIM
Published: April 2006

Planned villagization is a recurrent feature in modern Africa. Apart from their official goals, which were missed in most cases, rural settlement schemes can be seen as attempts by colonial and postcolonial states to inscribe a new territorial order into the countryside. Taking a group of villages in northwest Zambia as an example, this article examines the process and impact of territorialization in a long-term and interactionist perspective. The result is a history of contestation about competing concepts of spatiality and sociality which opens new perspectives on the making of both locality and the nation state in Central Africa.
LAGOS AND THE INVENTION OF JUVENILE DELINQUENCY IN NIGERIA, 1920–60
Authors: FOURCHARD LAURENT
Published: April 2006

This paper seeks to trace the origins of offences by youths as a distinct social concern in Lagos and examines the categorization of a group, the ‘juvenile delinquent’, by colonial administrators and welfare officers. While organized pickpocketing and prostitution by young people emerged as an issue in Nigerian newspapers in the 1920s, it was largely ignored by local administrators until the appointment, in 1941, of the first Social Welfare Officer. This led to the implementation of new administrative and judiciary machinery which combined two processes: it legislated ‘juvenile delinquency’ into existence as a clearly identifiable social problem; and criminalized a large portion of urban youth, especially female hawkers. The combination of these processes constitutes what can be called the invention of juvenile delinquency in Nigeria.
Is intralesional cidofovir worthwhile in juvenile recurrent respiratory papillomatosis?
Authors: Sheahan P , Sexton S , Russell J D
Published: April 2006

Objective: To investigate the efficacy of intralesional cidofovir in the treatment of recurrent respiratory papillomatosis (RRP) in children.

Methods: Prospective observational study of four consecutive children with RRP treated at an academic tertiary children's hospital. Laryngo-bronchoscopy was performed at three- to five-weekly intervals. Photodocumentation was obtained and disease severity assessed using an anatomical RRP severity score. Surgical debulking of large papillomas was then performed, and cidofovir (5 mg/ml) injected into any remaining papillomas as well as submucosally at the sites of resected papillomas. The efficacy of cidofovir was assessed by the change in papilloma severity score over the course of the treatment.

Results: Complete disease remission was obtained in one patient, with a partial response seen in two others. One patient showed no significant response. The greatest beneficial effect was seen after the fourth cidofovir injection; however, two patients demonstrated a deterioration in severity scores after treatment was withheld at this point. Both responded well to further cidofovir injections. However, a clear plateau in the response to cidofovir was seen in all patients by the eighth injection.

Conclusion: Intralesional cidofovir may help control papilloma regrowth and reduce disease severity in many children with RRP. In most cases, cidofovir would appear to be less efficacious in causing disease eradication. There appears to be little evidence to support prolonged treatment regimes (i.e. more than eight treatments).
Divine hiddenness and the demographics of theism
Authors: MAITZEN STEPHEN
Published: April 2006

According to the much-discussed argument from divine hiddenness, God's existence is disconfirmed by the fact that not everyone believes in God. The argument has provoked an impressive range of theistic replies, but none has overcome – or, I suggest, could overcome – the challenge posed by the uneven distribution of theistic belief around the world, a phenomenon for which naturalistic explanations seem more promising. The ‘demographics of theism’ confound any explanation of why non-belief is always blameworthy or of why God allows blameless non-belief. They also cast doubt on the existence of a sensus divinitatis: the awareness of God that Reformed epistemologists claim is innate in all normal human beings. Finally, the demographics make the argument from divine hiddenness in some ways a better atheological argument than the more familiar argument from evil.
Exclusivism versus pluralism in religion: a response to Kevin Meeker
Authors: HICK JOHN
Published: April 2006

I argue that Meeker is mistaken in two crucial respects. First, contrary to both myself and Plantinga, he treats exclusivism as a theory about the relation between the religions, and then claims that it is superior to the pluralist theory. But he does not say what his exclusivist theory is. Second, he bases his claim of a fundamental self-contradiction in my pluralist position on a view which I disavow, namely that altruism is the core of religion. He omits the central idea of a profound reorientation in response to the Real, of which altruism is a manifestation.
Pluralism, exclusivism, and the theoretical virtues
Authors: MEEKER KEVIN
Published: April 2006

This paper argues that John Hick's commitment to the moral principle of altruism undermines his pluralistic claim that all of the major world religions are equally efficacious from a soteriological perspective. This argument is placed in a context of a discussion evaluating the theoretical virtues of various hypotheses about religious diversity.
Errors of regional mass variations inferred from GRACE monthly solutions
Authors: Horwath Martin , Dietrich Reinhard
Published: April 2006

Error correlations in current GRACE monthly gravity field models strongly affect the errors of inferred regionally averaged mass variations (RMV). To demonstrate this, we develop an empirical method which roughly estimates scaling factors to convert error bars computed by ignoring error correlations into more realistic error bars for RMV. For current solutions by CSR and GFZ, we find factors in the order of 2 or more for near‐polar regions and below one for near‐equatorial regions. A comparison of RMV computed from the CSR and the GFZ models for Greenland, Antarctica and the Amazon basin supports our findings. We discuss consequences on error assessment and error separation. For example, previously published GRACE‐derived RMV of Greenland may be still strongly affected by errors in the GRACE products.
Investigating superswells and sea level changes caused by superplumes via normal mode relaxation theory
Authors: Barletta V. R. , Sabadini R.
Published: April 2006

The superplume hypothesis, particularly for one in the mid‐Cretaceous, has stimulated the search for evidence for or against such an event and the associated superswell. An approach based on normal mode relaxation theory makes it possible to simulate the surface deformation caused by the rising plume using a spherical, self‐gravitating and stratified viscoelastic Earth model. The results for the superswell are consistent with those of previous analyses using convection and experimental modeling. The self‐consistent coupling of elastic and viscous properties based on Maxwell rheology reveals that elasticity plays an important role contributing up to 30% to surface swelling when the plume head crosses the upper mantle. We show that the deformation at great distances from the superswell is relatively small, of the order of meters at most, and opposite in sign with respect to the large uplift over the plume, of the order of kilometers. The global subsidence over a wide region of the planet surrounding the superswell counteracts its effects on sea level changes and triggers a “eustatic” signal of a few meters at most, a negligible magnitude with respect to 250 m characteristic for the mid‐Cretaceous. Previous arguments against the mid‐Cretaceous superplume hypothesis, which assume that the large amount of water displaced by the superswell causes a “eustatic” sea level rise of about 200 m thus competing with the displacement due to oceanic crust production, are no longer tenable since such estimates did not account for the global behavior of the planet under internal loads.
Measurement and modeling of HF channel directional spread characteristics for northerly paths
Authors: Warrington E. M. , Stocker A. J. , Siddle D. R.
Published: April 2006

The northerly ionosphere is a dynamic propagation medium that causes HF signals reflected from this region to exhibit delay spreads and Doppler shifts and spreads that significantly exceed those observed over midlatitude paths. Since the ionosphere is not perfectly horizontally stratified, the signals associated with each propagation mode may arrive at the receiver over a range of angles in both azimuth and elevation. Such large directional spreads may have a severe impact on radio systems employing multielement antenna arrays and associated signal‐processing techniques since the signal environment does not comprise a small number of specular components as often assumed by the processing algorithms. In order to better understand the directional characteristics of HF signals reflected from the northerly ionosphere, prolonged measurements have recently been made over two paths: (1) from Svalbard to Kiruna, Sweden, and (2) from Kirkenes, Norway, to Kiruna. An analysis of these data is presented in this paper. The directional characteristics are summarized, and consideration is given to modeling the propagation effects in the form of a channel simulator suitable for the testing of new equipment and processing algorithms.
Optical control of the coherent acoustic vibration of metal nanoparticles
Authors: Arbouet A. , Del Fatti N. , Vallee F.
Published: April 2006

Optical control of the coherent breathing vibrations of silver nanospheres is demonstrated using a high-sensitivity femtosecond pump-probe technique in a double-pump pulse configuration. Oscillation of the fundamental mode that usually dominates the time-domain vibrational response can thus be stopped, permitting observation of the first order radial mode and determination of its properties. These are found to be in agreement with the predictions of the model of an elastic sphere embedded in an elastic matrix.
Thickness dependent swift heavy ion irradiation effects on electronic transport of (La0.5Pr0.2)Ba0.3MnO3 thin films
Authors: Markna J. H. , Parmar R. N. , Kuberkar D. G. , Kumar Ravi , Rana D. S. , Malik S. K.
Published: April 2006

Electrical resistivity and magnetoresistance measurements on (La0.5Pr0.2)Ba0.3MnO3 thin films of 50 and 200nm thicknesses, irradiated by 200MeV Ag+15 ions, have been carried out. Before irradiation, all the films exhibit insulator-metal transition at a temperature (Tp) of ∼200K. After irradiation, both resistivity and Tp remain mostly unaffected in 50nm thin film but vary largely in 200nm thin films. This disparity in irradiation effect on these films is explained to arise from the interplay of columnar defect induced (i) enhancement in resistivity with increasing thickness of the film and (ii) local release of strain at the interfaces of low thickness films, which decreases resistivity.
Cooperative solid-vapor-phase epitaxy: An approach for fabrication of single-crystalline insulator/Si/insulator nanostructures
Authors: Fissel A. , Kühne D. , Bugiel E. , Osten H. J.
Published: April 2006

We study the growth of insulator/Si/insulator nanostructures on Si(111) using molecular beam epitaxy. Based on different investigations, we develop an approach for the fabrication of a nanostructure with a continuous ultrathin single-crystalline silicon buried in a single-crystalline insulator matrix with sharp interfaces. This approach is based on an epitaxial encapsulated solid-phase epitaxy, in which the solid-phase epitaxy of silicon is accompanied by a vapor-phase epitaxy of the second insulator layer. We call this approach as cooperative solid-vapor-phase epitaxy. As an example we demonstrate the growth of buried epitaxial silicon in epitaxial Gd2O3.
Growth and depth dependence of visible luminescence in wurtzite InN epilayers
Authors: Pu X. D. , Shen W. Z. , Zhang Z. Q. , Ogawa H. , Guo Q. X.
Published: April 2006

We present detailed investigation of growth and depth dependence of visible (∼1.9eV) photoluminescence (PL) in wurtzite InN epilayers grown by magnetron sputtering. For normal surface incidence, PL peak was found to redshift with increasing growth temperatures. Cross-sectional PL measurements were able to separate contributions from the InN epilayers and sapphire substrates, which not only demonstrated the visible luminescence in InN but also revealed the blueshift of the PL peak with laser spot focusing from epilayer surface toward the interface. The results have been well explained by the growth mechanism and residual strain along growth direction of InN epilayers.
Spectral statistics in natural scenes predict hue, saturation, and brightness
Authors: Long Fuhui , Yang Zhiyong , Purves Dale
Published: April 2006

The perceptual color qualities of hue, saturation, and brightness do not correspond in any simple way to the physical characteristics of retinal stimuli, a fact that poses a major obstacle for any explanation of color vision. Here we test the hypothesis that these basic color attributes are determined by the statistical covariations in the spectral stimuli that humans have always experienced in typical visual environments. Using a database of 1,600 natural images, we analyzed the joint probability distributions of the physical variables most relevant to each of these perceptual qualities. The cumulative density functions derived from these distributions predict the major colorimetric functions that have been reported in psychophysical experiments over the last century.
CeRh1 (
rhr-1
) is a dominant Rhesus gene essential for embryonic development and hypodermal function in
Caenorhabditis elegans
Authors: Ji Qiongmei , Hashmi Sarwar , Liu Zhi , Zhang Jun , Chen Ying , Huang Cheng-Han
Published: April 2006

Rhesus (Rh) proteins share a conserved 12-transmembrane topology and specify a family of putative CO
2
channels found in diverse species from microbes to human, but their functional essentiality and physiological importance in metazoans is unknown. To address this key issue and analyze Rh-engaged physiologic processes, we sought to explore model organisms with fewer Rh genes yet are tractable to genetic manipulations. In this article, we describe the identification in nematodes of two Rh homologues that are highly conserved and similar to human Rh glycoproteins, and we focus on their characterization in
Caenorhabditis elegans
. RNA analysis revealed that CeRh1 is abundantly expressed in all developmental stages, with highest levels in adults, whereas CeRh2 shows a differential and much lower expression pattern. In transient expression in human cells, both CeRh1 and CeRh2-GFP fusion proteins were routed to the plasma membrane. Transgenic analysis with GFP or LacZ-fusion reporters showed that CeRh1 is mainly expressed in hypodermal tissue, although it is also in other cell types. Mutagenesis analysis using deletion constructs mapped a minimal promoter region driving CeRh1 gene expression. Although CeRh2 was dispensable, RNA interference with CeRh1 caused a lethal phenotype mainly affecting late stages of
C. elegans
embryonic development, which could be rescued by the CbRh1 homologue from the worm
Caenorhabditis briggsae
. Taken together, our data provide direct evidence for the essentiality of the CeRh1 gene in
C. elegans
, establishing a useful animal model for investigating CO
2
channel function by cross-species complementation.
ProMAT: protein microarray analysis tool
Authors: White Amanda M. , Daly Don S. , Varnum Susan M. , Anderson Kevin K. , Bollinger Nikki , Zangar Richard C.
Published: April 2006

Summary: ProMAT is a software tool for statistically analyzing data from enzyme-linked immunosorbent assay microarray experiments. The software estimates standard curves, sample protein concentrations and their uncertainties for multiple assays. ProMAT generates a set of comprehensive figures for assessing results and diagnosing process quality. The tool is available for Windows or Mac, and is distributed as open-source Java and R code.

Availability: ProMAT is available at . ProMAT requires Java version 1.5.0 and R version 1.9.1 (or more recent versions). ProMAT requires either Windows XP or Mac OS 10.4 or newer versions.

Contact:  amanda.white@pnl.gov
NQ-Flipper: validation and correction of asparagine/glutamine amide rotamers in protein crystal structures
Authors: Weichenberger Christian X. , Sippl Manfred J.
Published: April 2006

Summary: The error rate of asparagine (Asn) and glutamine (Gln) amide rotamers in protein crystal structures is in the order of 20% and as a consequence the current Protein Database (PDB) contains approximately half a million incorrect Asn and Gln side-chain rotamers. Here we present NQ-Flipper, a web service based on knowledge-based potentials of mean force to automatically detect and correct erroneous rotamers. We achieve excellent agreement with expert curated data.

Availability: The program is accessible freely as a web service at

Contact:  sippl@came.sbg.ac.at
ALTree: association detection and localization of susceptibility sites using haplotype phylogenetic trees
Authors: Bardel Claire , Danjean Vincent , Génin Emmanuelle
Published: April 2006

Summary: Finding the genes involved in complex diseases susceptibility and among those genes, localizing the variant sites explaining this susceptibility is a major goal of genetic epidemiology. In this context, haplotypic methods that use the joint information on several markers may be of particular interest. When the number of haplotypes is large, a grouping may be required. Phylogenetic trees allow such groupings of haplotypes based on their evolutionary history and may help in the detection and localization of disease susceptibility sites. In this paper, we present a new software to perform phylogeny-based association and localization analysis.

Availability: The software package, including all documentation and example files, is freely available at . It is distributed under the GPL license.

Contact:  bardel@vjf.inserm.fr
Computational recognition of potassium channel sequences
Authors: Heil Burkhard , Ludwig Jost , Lichtenberg-Fraté Hella , Lengauer Thomas
Published: April 2006

Motivation: Potassium channels are mainly known for their role in regulating and maintaining the membrane potential. Since this is one of the key mechanisms of signal transduction, malfunction of these potassium channels leads to a wide variety of severe diseases. Thus potassium channels are priority targets of research for new drugs, despite the fact that this protein family is highly variable and closely related to other channels, which makes it very difficult to identify new types of potassium channel sequences.

Results: Here we present a new method for identifying potassium channel sequences (PSM, Property Signature Method), which—in contrast to the known methods for protein classification—is directly based on physicochemical properties of amino acids rather than on the amino acids themselves. A signature for the pore region including the selectivity filter has been created, representing the most common physicochemical properties of known potassium channels. This string enables genome-wide screening for sequences with similar features despite a very low degree of amino acid similarity within a protein family.

Availability: The PSM software will be made available on request from the corresponding author.

Contact:  Burkhard.Heil@gmail.com

Supplementary information: Supplementary data are available at Bioinformatics online.
A multiplicity result for a nonlinear degenerate problem arising in the theory of electrorheological fluids
Authors: Mihăilescu Mihai , Rădulescu Vicenţiu
Published: April 2006

We study the boundary value problemin,u=0 on, whereis a smooth bounded domain inandis a-Laplace type operator, with. We prove that ifλis large enough then there exist at least two non-negative weak solutions. Our approach relies on the variable exponent theory of generalized Lebesgue–Sobolev spaces, combined with adequate variational methods and a variant of the Mountain Pass lemma.
General up to next-nearest-neighbour elasticity of triangular lattices in three dimensions
Authors: Dubus Cyril , Sekimoto Ken , Fournier Jean-Baptiste
Published: April 2006

We establish the most general form of the discrete elasticity of a two-dimensional triangular lattice embedded in three dimensions, taking into account up to next-nearest-neighbour interactions. Besides crystalline system, this is relevant to biological physics (e.g. red blood cell cytoskeleton) and soft matter (e.g. percolating gels, etc.). In order to correctly impose the rotational invariance of the bulk terms, it turns out to be necessary to take into account explicitly the elasticity associated with the vertices located at the edges of the lattice. We find that some terms that were suspected in the literature to violate rotational symmetry are, in fact, admissible.
A fast method for nonlinear three-dimensional free-surface waves
Authors: Fochesato Christophe , Dias Frédéric
Published: April 2006

An efficient numerical model for solving fully nonlinear potential flow equations with a free surface is presented. Like the code that was developed by Grilli
et al
. (Grilli
et al
. 2001
Int. J. Numer. Methods Fluids
35
, 829–867), it uses a high-order three-dimensional boundary-element method combined with mixed Eulerian–Lagrangian time updating, based on second-order explicit Taylor expansions with adaptive time-steps. Such methods are known to be accurate but expensive. The efficiency of the code has been greatly improved by introducing the fast multipole algorithm. By replacing every matrix–vector product of the iterative solver and avoiding the building of the influence matrix, this algorithm reduces the computing complexity from

to nearly

, where
N
is the number of nodes on the boundary. The performance of the method is illustrated by the example of the overturning of a solitary wave over a three-dimensional sloping bottom. For this test case, the accelerated method is indeed much faster than the former one, even for quite coarse grids. For instance, a reduction of the complexity by a factor six is obtained for
N
=6022, for the same global accuracy. The acceleration of the code allows the study of more complex physical problems and several examples are presented.
Biological characterization of human immunodeficiency virus type 1 subtype C protease carrying indinavir drug-resistance mutations
Authors: Gonzalez Luis M. F. , Aguiar Renato S. , Afonso Adriana , Brindeiro Patricia A. , Arruda Mônica B. , Soares Marcelo A. , Brindeiro Rodrigo M. , Tanuri Amílcar
Published: April 2006

Human immunodeficiency virus type 1 subtype C isolates belong to one of the most prevalent strains circulating worldwide and are responsible for the majority of new infections in the sub-Saharan region and other highly populated areas of the globe. In this work, the impact of drug-resistance mutations in the protease gene of subtype C viruses was analysed and compared with that of subtype B counterparts. A series of recombinant subtype C and B viruses was constructed carrying indinavir (IDV)-resistance mutations (M46V, I54V, V82A and L90M) and their susceptibility to six FDA-approved protease inhibitor compounds (amprenavir, indinavir, lopinavir, ritonavir, saquinavir and nelfinavir) was determined. A different impact of these mutations was found when nelfinavir and lopinavir were tested. The IDV drug-resistance mutations in the subtype C protease backbone were retained for a long period in culture without selective pressure when compared with those in subtype B counterparts in washout experiments.
Sialic acid is a receptor determinant for infection of cells by avian Infectious bronchitis virus
Authors: Winter Christine , Schwegmann-Weßels Christel , Cavanagh Dave , Neumann Ulrich , Herrler Georg
Published: April 2006

The importance of sialic acid for infection by avian Infectious bronchitis virus (IBV) has been analysed. Neuraminidase treatment rendered Vero, baby hamster kidney and primary chicken kidney cells resistant to infection by the IBV-Beaudette strain. Sialic acid-dependent infection was also observed with strain M41 of IBV, which infects primary chicken kidney cells but not cells from other species. In comparison with Influenza A virus and Sendai virus, IBV was most sensitive to pre-treatment of cells with neuraminidase. This finding suggests that IBV requires a greater amount of sialic acid on the cell surface to initiate an infection compared with the other two viruses. In previous studies, with respect to the haemagglutinating activity of IBV, it has been shown that the virus preferentially recognizes α2,3-linked sialic acid. In agreement with this finding, susceptibility to infection by IBV was connected to the expression of α2,3-linked sialic acid as indicated by the reactivity with the lectin Maackia amurensis agglutinin. Here, it is discussed that binding to sialic acid may be used by IBV for primary attachment to the cell surface; tighter binding and subsequent fusion between the viral and the cellular membrane may require interaction with a second receptor.
1-(2-Chlorobenzoyl)-3-phenylthiourea
Authors: Khawar Rauf M. , Badshah Amin , Saeed Aamer , Bolte Michael
Published: April 2006

The phenyl and benzoyl groups in the title molecule, C14H11ClN2OS, are cis and trans, respectively, with respect to the C=S bond. The molecular conformation is stabilized by an N—H...O hydrogen bond and the crystal packing is characterized by N—H...O and N—H...S hydrogen bonds.
Reinvestigation of cadmium diphosphate
Authors: Bouchelaghem Wahiba , Benloucif Med Rida , Mayoufi Moussa , Benmoussa Amar , Schenk Kurt J.
Published: April 2006

The crystal structure of the title compound, Cd2P2O7, has been reinvestigated by means of an image-plate diffraction system. The study confirms the previously determined structure [Calvo & Au (1969). Can. J. Chem.
47, 3409–3417], but provides a less biased model and higher precision. The structure consists of alternating layers of isolated P2O7 groups and edge-sharing CdO6 octahedra forming corrugated chains along [1\overline{1}0]. The layers and the parallel chains interconnect by means of corner-sharing. This room-temperature structure is actually the average of a modulated structure, which might partly rectify the unusual bond valences.
Ethyl 1-methylimidazole-2-carboxylate
Authors: Frye Brian C. , Mashuta Mark S. , Mullins Christopher S. , Grapperhaus Craig A. , Buchanan Robert M.
Published: April 2006

The title compound, C7H10N2O2, crystallizes as a nearly planar molecule. The carboxyethyl group is twisted by 4.43 (14)° relative to the plane that includes the imidazole group. The carbonyl unit of the carboxyethyl group is oriented anti to the N-methyl group of the imidazole.
5-Chlorosalicylaldehyde salicylhydrazone
Authors: Yang De-Suo
Published: April 2006

The molecule of the title compound, C14H11ClN2O3, is roughly planar and displays a trans configuration with respect to the C=N double bond. The crystal structure is stabilized by intermolecular O—H...O hydrogen bonds.
Baby Wordsmith
Authors: Golinkoff Roberta Michnick , Hirsh-Pasek Kathy
Published: April 2006

How do infants acquire their first words? Word reference, or how words map onto objects and events, lies at the core of this question. The emergentist coalition model (ECM) represents a new wave of hybrid developmental theories suggesting that the process of vocabulary development changes from one based in perceptual salience and association to one embedded in social understanding. Beginning at 10 months, babies learn words associatively, ignoring the speaker's social cues and using perceptual salience to guide them. By 12 months, babies attend to social cues, but fail to recruit them for word learning. By 18 and 24 months, babies recruit speakers' social cues to learn the names of particular objects speakers label, regardless of those objects' perceptual attraction. Controversies about how to account for the changing character of word acquisition, along with the roots of children's increasing reliance on speakers' social intent, are discussed.
Pulmonary hypertension in thalassaemia major patients with normal left ventricular systolic function
Authors: Hagar R. W. , Morris C. R. , Vichinsky E. P.
Published: April 2006

Pulmonary hypertension is common in adults with thalassaemia and other haemolytic anaemias. It was hypothesised that regular transfusions in thalassaemia major should both decrease the chronic haemolytic rate and be protective from pulmonary hypertension (PHT). To reduce the contribution of existing cardiac disease to PHT, the subjects were limited to patients with normal left ventricular shortening fractions. Associations with multiple laboratory markers of haemolysis, serum ferritin levels, chest X‐rays findings and splenectomy status were also considered. We found no biochemical, transfusional, or clinical (except gender) differences in transfused thalassaemia patients with or without pulmonary hyper tension.
Cytological studies on a new species of rickettsia found in association with a phage in the digestive gland of the marine bivalve mollusc, Tellina tenuis (da Costa)
Authors: BUCHANAN J. S.
Published: April 2006

Abstract. The secretory cells of the digestive glands of up to 75% of Tellina tenuis from sheltered sandy beaches on the Scottish coast contained intracytoplasmic inclusion bodies consisting of microcolonies of a rickettsia‐like organism. The development and morphology of these parasitic bacteria and the cytopathic effect on the host cells are described. These features closely resemble those of the genus Coxiella of the family Rickettsiaceae. It was possible to culture the organism in embryonated hens' eggs. Scattered particles and paracrystalline arrays of a virus were seen in association with the bacteria. This is believed to be the first description of a phage from a rickettsia.
The effect of temperature on agglutination activity of coho salmon Oncorhynchus kisutch (Walbaum) antiserum
Authors: O'LEARY P. J. , CISAR J. O. , FRYER J. L.
Published: April 2006

Abstract. The effects of temperature on the activity of antisera from coho salmon (oncorhynchus kisutch) and from rabbit were compared. Agglutination activity of salmon anti‐Aeromonas salmonicida serum declined following incubation at 55°C whereas rabbit antiserum lost agglutination activity after incubation at 65°C.
Ecological observations on the commercial sand crab, Portunus pelagicus (L.), and its parasite, Sacculina granifera Boschma, 1973 (Cirripedia: Rhizocephala)
Authors: PHILLIPS W. J. , CANNON L. R. G.
Published: April 2006

Abstract. Sacculina granifera was found in 12% of commercial sandcrabs, Portunus pelagicus, in Moreton Bay irrespective of sex. Although male and female crabs were randomly distributed about Moreton Bay, egg bearing females were most common at the seaward station. This and the distribution of epizoic barnacles on gills and carapace suggest the sexes school separately. The increased prevalence of barnacles on the carapace of infected crabs indicates Sacculina inhibits moulting. The distribution of interna infections in small crabs towards south and west and externa infections in large crabs in the easterly, seaward stations suggests Sacculina preferentially attacks young crabs as they move inshore and then induces crabs to behave like ‘berried’ (i.e. egg bearing) females by moving seaward as they grow. Morphologically female crabs are little changed by Sacculina, but the males show considerable modification which is reflected most accurately in the shortening of the chelar propodus to proportions similar to normal females. Infected crabs are sterile and internally the hepatopancreas becomes green rather than tan. Parasitized crabs were seen to groom their externae as ‘berried’ females groom their egg masses.
The histopathology of Stephanochasmus baccatus Nicoll, 1907 in the digestive gland of Buccinum undatum (L.)
Authors: SOMMERVILLE CHRISTINA
Published: April 2006

Abstract. Samples of Buccinum undatum (L.), a marine carnivorous prosobranch, from the Loch Ewe area of the West Coast of Scotland were found to be infected with the larval stages of Stephanochasmus baccatus Nicoll, 1907. The digestive glands of infected and uninfected molluscs were examined histologically and the pathogenesis of the larval stages in the digestive gland are described. Two types of lesion were found to occur. In Type I lesions degenerative changes were confined to individual tubules and neighbouring tubules remained unaffected. The Type I lesion was the typical response to the presence of the parasite in the digestive gland. The Type II lesion was less common and was associated with very heavy infections in the early part of the molluscan cycle of infection. In these molluscs large areas of the digestive gland were destroyed, and there was a marked cellular infiltrate of putatively inflammatory cells.
Studies on the epizootiology of Myxobolus insidiosus Wyatt and Pratt, 1963 (Protozoa: Myxosporida)
Authors: WYATT E. J.
Published: April 2006

Abstract. Myxobolus insidiosus from the striated musculature of chinook salmon, Oncorhynchus tshawytscha (Walbaum), was studied in disease free and naturally contaminated waters. Infection could not be induced in susceptible fish in a disease free water supply by any means triad. Experiments in naturally contaminated waters provided data on minimum and other exposure times. Studies were also carried out on the effect of water temperature, different substrates and flow rates, time of year and size of fish on infection. The rainbow trout, Salmo gairdneri Richardson, was also checked for infection and not found with this disease in naturally contaminated waters. Transovarian infection was ruled out.
Vertebral dysplasia in young fish exposed to the herbicide trifluralin
Authors: COUCH J. A. , WINSTEAD J. T. , HANSEN D. J. , GOODMAN L. R.
Published: April 2006

Abstract. Sheepshead minnows, Cyprinodon variegatus Lacépède, exposed to 5.5 to 31 μg/1 of the herbicide trifluralin, throughout their first 28 days of life, developed a heretofore undescribed vertebral dysplasia. This dysplasia consisted of semi‐symmetrical hypertrophy of vertebrae (three to 20 times normal), characterized by foci of osteoblast and fibroblasts actively laying down bone and bone precursors. Effects of the abnormal vertebral development were dorsal vertebral growth into the neural canal, ventral compression of renal ducts, and longitudinal fusion of vertebrae. Pish, exposed for 51 days to 16.6 μg/1 trifluralin and thereafter depurated for 41 days, showed no increase in vertebral dysplasia during depuration; however, residual spinal column damage was evident. Serum calcium concentrations were elevated in adult fish exposed for 4 days to 16.6 μg/1 trifluralin. Fluorosis or mimicry of hypervitaminosis A are considered possible mechanisms for the osseous effect, but are not considered to be the only possible causes. The highly predictable nature of this disorder in experimental exposures strengthens the probability that young fish may serve as experimental models for determining effects of chemicals on early vertebrate ontogeny, particularly in regard to skeletal development.
Tumours and microbial diseases of marine fishes in Alaskan waters
Authors: McCAIN B. B. , GRONLUND W. D. , MYERS M.S. , WELLINGS S. R.
Published: April 2006

Abstract. In an effort further to define the current health status of demersal fish in the Bering Sea, 36 618 fish captured by otter trawl during 1976 were examined for pathological conditions. Of the 26 species examined, 22 were found to have no detectable abnormalities. The four species with abnormalities were Pacific cod Gadus macrocephalus Tilesius with pseudobranchial tumours and skin lesions, walleye pollock Theragra chalcogramma (Pallas) with pseudobranchial tumours, yellowfin sole Limanda aspera (Pallas) with lymphocystis, and rock sole Lepidopsetta bilineata (Ayres) with epidermal papillomas. The prevalence, geographical distribution and biological and pathological characteristics of affected individuals were determined.

Pseudobranchial tumours of both Pacific cod and walleye pollock were occasionally found to be invasive. Fish bearing these tumours were distributed throughout the sampling area. The epidermal papillomas on rock sole resembled similar tumours found on several flatfish species along the West Coast of North America. The distribution of this disease appeared to be depth related. The virus‐caused lymphocystis growths were located on the ‘blind’ side of yellowfin sole. The highest frequencies of fish with lymphocystis were in the south‐eastern Bering Sea. Two main types of skin lesions were seen on Pacific cod: ulcers and ring‐shaped lesions. Isolates of bacteria (Pseudomonas sp.) were routinely obtained from the cod ulcers and may be the cause of this disease. The ring‐shaped skin lesions, when examined microscopically, contained unidentified epidermal basophilic bodies.
The prevention of liver lipoid degeneration (ceroidosis) and microcytic anaemia in rainbow trout Salmo gairdneri Richardson fed rancid diets: a preliminary report
Authors: SMITH C. E.
Published: April 2006

Abstract. Feeding a rancid diet deficient in Vitamins C and E to 13 g rainbow trout resulted in growth depression, microcytic anaemia and liver lipoid degeneration. Trout fed the rancid diet containing Vitamins CandE grew as well as control fish fed a non‐rancid diet and did not develop microcytic anaemia or liver lipoid degeneration, The symptoms that developed in deficient fish are typical of those resulting from Vitamin E but not Vitamin C deficiency. The results suggest that Vitamin E is important in preventing growth depression, microcytic anaemia and liver lipoid degeneration in rainbow trout fed rancid diets.
Infectious haematopoietic necrosis in rainbow trout Salmo gairdneri Richardson in a semi‐closed system
Authors: CARLISLE J. C. , SCHAT K. A. , ELSTON R.
Published: April 2006

Abstract. An outbreak of infectious haematopoietic necrosis causing high mortality in rainbow trout fry occurred in New York State. Despite the fact that the hatchery effluent was recycled, spread of viral infection or of clinical disease was not demonstrated.

Endocardial and glomerular endothelial necrosis and fibrinous peritonitis were among the histopathologic changes seen. Many of the signs and lesions were similar to those seen in infectious pancreatic necrosis.
Virus infections of marine fish erythrocytes: prevalence of piscine erythrocytic necrosis in cod Gadus morhua L. and blenny Blennius pholis L. in coastal and offshore waters of the United Kingdom
Authors: SMAIL D. A. , EGGLESTONE S. I.
Published: April 2006

Abstract. Giemsa stained blood smears prepared from blennies caught on the shores of southern England and from cod taken from the Celtic and North seas revealed fish with clinical ‘piscine erythrocytic necrosis’ (PEN). The findings recorded here extend the distribution data on PEN infections and report that the infection in the blenny and cod may possibly have a similar developmental pattern. Data are presented on the prevalence of the infection in the fish population samples and on the proportion of infected cells in the smears examined.
Effect of dietary Mirex and PCB's in combination with food deprivation and testosterone administration on thyroid activity and bioaccumulation of organochlorines in rainbow trout Salmo gairdneri Richardson
Authors: LEATHERLAND J. F. , SONSTEGARD R. A.
Published: April 2006

Abstract. Serum thyroxine (T4) and triiodothyroninc (T3) levels were significantly lower in fish fed a high PCB diet (500 mg/kg) in comparison to those fed the control diet. The differences in serum thyroid hormone levels between the PCB‐fed group and those fed the control diet were not evident after 14 days food deprivation nor after testosterone‐injection. The low PCB diet (50 mg/kg) was without effect on serum T4 and T3 levels regardless of the treatment. Trout fed the highest Mirex diet (50 mg/kg) had T3 levels which were significantly lower and a T4 T3 ratio which T3was still evident after 14 days food deprivation but after testosterone administration the serum T3 levels in the control fish had fallen to levels similar to those in the Mirex‐fed group. The low Mires diet (5 mg/kg) was without effect on serum T4 and T3 levels regardless of treatment. Serum T4 and T3 levels in fish fed a mixed PCB (50 mg/kg) and Mirex (5 mg/kg) diet were not significantly different from controls but T3 levels were significantly higher than in control fish after 14 days food deprivation and subsequent testosterone administration. There were no appearence difference in anterior pituitary or thyroid histology between the different groups. The hepatosomatic index (HSI) in PCB‐fed trout was significantly larger than in controls in the fed groups, but not after 14 days food deprivation and subsequent testosterone administration. There was a five‐fold difference in carcass PCB hioaccumulation between fish fed the two PCB‐conlaminated diets, despite a 10‐fold difference in dietary levels of the organochlorine. Similarly despite 10‐fold differences in dietary Mirex levels in fish fed the 5 and 50 mg/kg and the 50 and 500 mg/kg diets, there were only 4–56–and 1–35‐fold increases in carcass Mirex content, respectively. Trout fed the mixed Mirex‐PCB diet had PCB levels of only 60.2% of those fed comparable levels of PCB alone (50 mg/kg) but contained similar levels of Mirex to those fed Mirex alone (a mg/kg).
Tissue reactions to microsporidian infections in fish
Authors: DYKOVÁ IVA , LOM JIŘÍ
Published: April 2006

Abstract. Histopathological studies on natural and experimental infections of nineteen microsporidian species from fishes distinguished two types of tissue reactions.

The first type is characteristic of infections with xenoma‐inducing microsporidian species and comprises three successive stages: a weakly reactive stage, a productive stage with the formation of granulomas and a stage of granuloma involution. Following the first stage, tissue reactions are directed towards the isolation of the parasite and result in its complete elimination and host tissue repair. The extent of pathological changes probably depends on the number of parasite cells which initiated the infection.

The second type is represented by Pleistophora species infecting muscles or oocytes. Host tissue reaction is surprisingly slight during the schizogony and sporogony and does not tend to isolate the invaded muscle fibres. A slight lymphocytic infiltration of myosepta indicates the first stage of tissue reaction. The tissue reaction only reaches the productive stage when mature spores completely fill the contents of the infected muscle fibre. A thick wall of fibroblasts may be formed to demarcate the parasite mass as soon as it undergoes necrotic changes. The extent of pathological changes probably depends on the ability of early developmental stages of the parasite to spread the infection within the host.

In both types of tissue reaction, the spores are destroyed by complete digestion within host phagocytic cells.
Atkinsiella hamanaensis sp. nov. isolated from cultivated ova of the mangrove crab, Scylla serrata (Forsskål)*
Authors: BIAN B. Z. , EGUSA S.
Published: April 2006

Abstract. Atkinsiella hamanaensis sp. nov. a marine mastigomycete isolated from ova of the mangrove crab, Scylla serrata (Forsskål), is described and illustrated. The fungus grew over a temperature range of 15–32°C, with an optimum of 29–32°C. Its growth was observed in peptone‐yeast extract glucose broth containing 1–5% NaCl, with optimum growth at 2–3% NaCl concentration. At 6% or more NaCl concentration, growth was inhibited. Its pH tolerance ranged from 4 to 9.
Perfusion fixation and alcian‐blue PAS staining in histology and histopathology of teleost kidney
Authors: HENTSCHEL H. , FINKENSTADT* H.
Published: April 2006

Abstract. Perfusion fixation of trout kidney with picric‐acid: formaldehyde: acetic acid: ethanol mixture was compared with other methods as a fixative for staining with the alcian‐blue PAS technique. Perfusion fixation gave conspicuously better results for light microscopical purposes.