bluuebunny/crossref_metadata_2025 huggingface dataset:
On the roots of the orthogonal polynomials and residual polynomials associated with a conjugate gradient method
Authors: Manteuffel Thomas A. , Otto James S.
Published: October 2005

In this paper we explore two sets of polynomials, the orthogonal polynomials and the residual polynomials, associated with a preconditioned conjugate gradient iteration for the solution of the linear system Ax = b. In the context of preconditioning by the matrix C, we show that the roots of the orthogonal polynomials, also known as generalized Ritz values, are the eigenvalues of an orthogonal section of the matrix C A while the roots of the residual polynomials, also known as pseudo‐Ritz values (or roots of kernel polynomials), are the reciprocals of the eigenvalues of an orthogonal section of the matrix (C A)−1. When C A is selfadjoint positive definite, this distinction is minimal, but for the indefinite or nonselfadjoint case this distinction becomes important. We use these two sets of roots to form possibly nonconvex regions in the complex plane that describe the spectrum of C A.
Stability of block LU factorization
Authors: Demmel James W. , Higham Nicholas J. , Schreiber Robert S.
Published: October 2005

Many of the currently popular ‘block algorithms’ are scalar algorithms in which the operations have been grouped and reordered into matrix operations. One genuine block algorithm in practical use is block LU factorization, and this has recently been shown by Demmel and Higham to be unstable in general. It is shown here that block LU factorization is stable if A is block diagonally dominant by columns. Moreover, for a general matrix the level of instability in block LU factorization can be bounded in terms of the condition number K(A) and the growth factor for Gaussian elimination without pivoting. A consequence is that block LU factorization is stable for a matrix A that is symmetric positive definite or point diagonally dominant by rows or columns as long as A is well‐conditioned.
The geometric stiffness of thick shell triangular finite elements for large rotations
Authors: Levy R. , Gal E.
Published: October 2005

This paper is concerned with the development of the geometric stiffness matrix of thick shell finite elements for geometrically nonlinear analysis of the Newton type. A linear shell element that is comprised of the constant stress triangular membrane element and the triangular discrete Kirchhoff Mindlin theory (DKMT) plate element is ‘upgraded’ to become a geometrically nonlinear thick shell finite element. Perturbation methods are used to derive the geometric stiffness matrix from the gradient, in global coordinates, of the nodal force vector when stresses are kept fixed. The present approach follows earlier works associated with trusses, space frames and thin shells. It has the advantage of explicitness and clear physical insight. A special procedure, tailored to triangular elements is used to isolate pure rotations to enable stress recovery via linear elastic constitutive relations. Several examples are solved. The results compare well with those available in the literature. Copyright © 2005 John Wiley & Sons, Ltd.
Augmented canonical forms and factorization of graphs
Authors: Kaveh A. , Sayarinejad M. A.
Published: October 2005

The main aim of this paper is to generalize the previously developed canonical forms by different types of alterations and/or augmentations. These forms provide suitable tools for the decomposition of the matrices of special patterns and lead to efficient aproaches for calculating their eigenvalues.

Methods were developed for factorization of symmetric graphs into smaller subgraphs using decompostion and healings (Commun. Numer. Meth. Engng 2003; 19:125–136, 2004; 20:133–146, 2004; 20:889–910; Comput. Struct. 2004; 18:2229–2240). Further factorization was possible only when further symmetries were available. The main drawback was associated with non‐decomposiblity of some of the factors in early stages of decomposition, and in particular healing which often destroyed the symmetry. In this paper, the mathematical concepts related to certain symmetric and unsymmetric graphs are developed, making refined factorization of the graphs feasible. Examples are included to show the simplicity of the operations being involved. Copyright © 2005 John Wiley & Sons, Ltd.
Numerical simulation of fluid flow and temperature field in keyhole double‐sided arc welding process on stainless steel
Authors: Honggang Dong , Hongming Gao , Lin Wu
Published: October 2005

Double‐sided arc welding process powered by a single supply is a type of novel high‐production process. In comparison with the conventional single‐sided arc welding, this process has remarkable advantages in enhancing penetration, minimizing distortion and improving welding production. In this paper, a three‐dimensional steady numerical model is developed for the heat transfer and fluid flow in plasma arc (PA)–gas tungsten arc (GTA) double‐sided keyhole welding process. The model considers the surface tension gradient, electromagnetic force and buoyancy force. A CCD camera is used to observe the size and shape of the keyhole and weld pool. The acquired images are analysed through image processing to obtain the surface diameters of the keyhole on the two sides. A double‐V‐shaped keyhole geometry is then proposed and its characteristic parameters are derived from the images and cross‐section of weld bead. In the numerical model, the keyhole cavum within the weld pool is treated as a whole quality, whose temperature is fixed at the boiling point of the workpiece material. The heat exchange between the keyhole and weld pool is treated as an interior boundary of the workpiece. Based on the numerical model, the distributions of the fluid flow and temperature field are calculated. A comparison of cross‐section of the weld bead with the experimental result shows that the numerical model's accuracy is reasonable. Copyright © 2005 John Wiley & Sons, Ltd.
Space‐time finite elements incorporating characteristics for the burgers' equation
Authors: Varoḡlu Erol , Liam Finn W. D.
Published: October 2005

A new finite element method is presented for the numerical solution of the Burgers' equation. The method is based on a weighted residual formulation in which the method of characteristics is incorporated by employing isoparametric space–time elements with the sides joining the nodes at subsequent time levels oriented along the characteristic lines of the hyperbolic partial differential equation associated with the Burgers' equation.

This method is capable of solving the Burgers' equation accurately for values of viscosity ranging from very small to large. The utility and accuracy of the method are demonstrated by a number of examples and a comparison of the numerical results with the exact solution is presented in one case.
Automated adaptive two‐dimensional system for the hp‐version of the finite element method
Authors: Georges M. K. , Shephard M. S.
Published: October 2005

This paper presents an automated, adaptive finite element modelling system based on the hp‐version of the finite element method. Error estimation and correction indication procedures with an automatic mesh generator and a p‐version analysis code are combined to provide a computationally efficient modelling environment. Error prediction techniques are employed to find the best combination of finite element discretization, h‐, and overall polynomial order, p‐, needed to achieve the prescribed level of accuracy. The automated adaptive modelling results demonstrate the capability of the modelling system of predicting discretizations to perform a p‐version finite element analysis to achieve prescribed levels of accuracy in the most efficient manner.
Synthesis of a thermoresponsive shell‐crosslinked 3‐layer onion‐like polymer particle with a hyperbranched polyglycerol core
Authors: Wan Decheng , Fu Qiang , Huang Junlian
Published: October 2005

A novel thermoresponsive shell crosslinked three‐layer onion‐like polymer particles were prepared using hyperbranched polyglycerol (PG) as parents compound, the periphery hydroxyl groups of PG were transformed into trithiocarbonates (SC(S)S) first; then, it was used as chain transfer agent to prepare star‐like block copolymer of N‐isopropyl acrylamide (NIPA) and N,N‐dimethylaminoethyl acrylate (DMA) in sequence via reversible addition fragmentation chain transfer (RAFT) process. Thus, a three‐layer polymer, PG[SC(S)S(DMA)b(NIPA)]n, was obtained. The middle layer of poly(DMA) was then crosslinked with 1,8‐diiodoctane, and the resulting onion‐like three‐layer polymer showed a lower critical solution temperature (LCST) in water because of the outer layer of poly(NIPA). The LCST value only slightly depended on the crosslinking degree. Finally, the SC(S)S were transformed into thiols by sequential treating with sodium borohydride and formic acid; thus, the core molecule was chemically detached from the crosslinked shell and a novel shell crosslinked polymer particle was obtained. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 5652–5660, 2005
Validation of the Distress Thermometer with bone marrow transplant patients
Authors: Ransom Sean , Jacobsen Paul B. , Booth‐Jones Margaret
Published: October 2005

The Distress Thermometer (DT) is a one‐item screening measure of psychological distress in cancer patients. This study examines the operating characteristics of the DT in patients about to undergo bone marrow transplant (BMT). Patients (N=491) completed the DT, the Center for Epidemiological Studies‐Depression Scale (CES‐D), the State‐Trait Anxiety Inventory‐State Version (STAI‐S), the ECOG Performance Status Scale, and the Patient Problem List. DT scores were related to higher depression, higher anxiety, and poorer performance status. Receiver operating characteristic (ROC) curve analyses of DT scores yielded area under the curve estimates of 0.75 when compared to the CES‐D cutoff score of 16, suggesting the DT has acceptable overall accuracy. The DT cutoff score of 4 had the greatest sensitivity and specificity when compared to the CES‐D cutoff score. Patients above this cutoff score reported worse ECOG scores and more practical, family, emotional, and physical problems (all p's⩽0.05) than those below the cutoff. The findings suggest the DT is a useful tool for screening for distress in BMT patients. The optimal DT cutoff score of 4 found here was identical to that found in another study using different criteria. This cutoff score also identified patients with problems likely to reflect psychological distress. Copyright © 2005 John Wiley & Sons, Ltd.
Non‐centrosymmetric molybdates CsLiMoO4 and CsLiMoO4·⅓H2O: crystal growth, polymorphism, efficient Stokes and anti‐Stokes generation and cascaded self‐frequency [χ(3)(SRS) → χ(2)(SFM)] conversion effects
Authors: Becker P. , Bohatý L. , Fröhlich R. , Eichler H. J. , Ueda K. , Takaichi K. , Hanuza J. , Maczka M. , Rhee H. , Kaminskii A. A.
Published: October 2005

The cover picture of this issue of physica status solidi (a) is a structure plot of the unit cells of CsLiMoO4 (left) and CsLiMoO4 · 1/3H2O (right). [MoO4] and [LiO4] groups are represented by green and yellow polyhedra, respectively, Cs is given by orange spheres. Smaller violet spheres represent possible positions of oxygen of water molecules in CsLiMoO4 · 1/3H2O, the occupation factor of these positions being 1/3.
A fast reflectance anisotropy spectrometer for in situ growth monitoring
Authors: Kaspari Christian , Pristovsek Markus , Richter Wolfgang
Published: October 2005

We report on an optical multichannel RAS (Reflectance Anisotropy Spectroscopy) setup capable of measuring at multiple photon energies simultaneously in the spectral range between 1.4 and 5.0 eV at a temporal resolution of up to 30 ms. The setup is specifically designed for time‐resolved studies of surface processes (e.g. epitaxial growth). Its accuracy was evaluated on static surfaces by comparison with RAS spectra acquired using a conventional scanning RAS setup. The performance was demonstrated by studying 2D island growth oscillations during GaAs epitaxy with TMGa and AsH3 or tBAs in metal‐organic vapour phase epitaxy (MOVPE). (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Ellipsometry from infrared to vacuum ultraviolet: Structural properties of thin anisotropic guanine films on silicon
Authors: Hinrichs K. , Silaghi S. D. , Cobet C. , Esser N. , Zahn D. R. T.
Published: October 2005

Bio‐molecular films of the DNA base guanine were characterized by ellipsometry from the Infrared (IR) to Vacuum Ultraviolet (VUV) spectral range, X‐ray diffraction (XRD) and atomic force microscopy (AFM). In this study we in particular focus on the contact‐less and reference‐free characterization of thin anisotropic bio‐molecular films by ellipsometry. Ellipsometric spectra in the IR as well as in the UV–VUV spectral range are molecule specific and the absorption bands could be used to identify molecules deposited on a substrate, since both the vibrational and electronic excitations are molecule specific. Especially we demonstrate that the measured pseudo‐dielectric function in the mid infrared (MIR) spectral range can be used as a characteristic “fingerprint” for DNA base molecules and their orientation in a thin film. Moreover an interpretation of the ellipsometric spectra in an optical model delivers the dielectric function and could give information about the molecular structure, orientation and conductivity. The determination of average molecular orientations from IR and UV/VUV ellipsometry spectra is discussed. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Erratum Shallow donor impurities in different shaped double quantum wells under the electric field [phys. stat. sol. (b) 241, No. 5, 1066–1072 (2004)]
Authors: Kasapoglu E. , Sokmen I.
Published: October 2005

For Eqs. (2a) and (2b) of the original article the correct versions are given. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Alkylation of enolates: An electrophilicity perspective
Authors: Elango M. , Parthasarathi R. , Subramanian V. , Chattaraj P. K.
Published: October 2005

Enolates are ambient nucleophiles, and alkylation can occur either at a carbon or at an oxygen site. It is known that the ratio of C/O alkylation depends significantly on various factors, including the type of enolate, alkylating agent, site of alkylation, and solvent environment. Analysis of regioselectivity and solvent effects on alkylation of lithium enolates is investigated using various reactivity descriptors, including generalized philicity. These results point out the reliability of both global and local reactivity descriptors in providing significant information about site selectivity and chemical reactivity of lithium enolates. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2006
Stable isotope variation in wool as a means to establish Turkish carpet provenance
Authors: Hedges Robert E. M. , Thompson Jonathon M. A. , Hull Bradley D.
Published: October 2005

The problem of establishing the provenance of carpets of artistic and historical importance is well known. We have addressed this by investigating whether there is sufficient geographical variation in the stable isotopes in wool (namely C, N and S) between key areas of Turkey to be able to recognize the different regions where carpets were made. Here we report results from modern wool samples taken from the winter growth of sheep in 2003/2004 from 13 carpet‐producing sites. Although each site has a characteristic composition, most sites cannot be distinguished from each other, and the overall isotopic pattern is unexpectedly complicated. Thus in Western Turkey there is no sign of sea‐spray effects in the δ34S values for sites close (10 km) to the sea, while, in the Konya Basin (Central Turkey), the δ34S values vary significantly between nearby sites. Two ‘urban’ settlements where sheep are now raised have dramatically higher δ15N values. It is nevertheless possible that certain production centers may have distinct signatures, and further work will compare carpets from known sources with the currently produced wool values. The results also provide additional insight into the natural variation found in archaeological faunal isotopic values, e.g. in bone collagen. Copyright © 2005 John Wiley & Sons, Ltd.
The Boolean functions computed by random Boolean formulas or how to grow the right function
Authors: Brodsky Alex , Pippenger Nicholas
Published: October 2005

We characterize growth processes (probabilistic amplification) by their initial conditions to derive conditions under which results such as Valiant's J Algorithms 5 (1984), 363–366 hold. We completely characterize growth processes that use linear connectives and generalize Savický's Discrete Math 147 (1990), 95–103 analysis to characterize growth processes that use monotone connectives. Additionally, we obtain explicit bounds on the convergence rates of several growth processes, including the growth process studied in Savický. © 2005 Wiley Periodicals, Inc. Random Struct. Alg., 2005
Diamniotic Conjoined Fetuses in a Triplet Pregnancy: An Insight into Embryonic Topology
Authors: Charles Adrian , Dickinson Jan E. , Watson Susan , Phillips Nevile , Yovich John
Published: October 2005

We present a case of triplets, 2 of whom were monochorionic diamniotic conjoined fetuses, and the other triplet was in a separate chorion. The pregnancy followed in vitro fertilization with 2 embryo transfers and the conjoined fetuses developed from a single embryo. An early ultrasound showed 2 embryos attached to 1 yolk sac. Further monitoring of the pregnancy showed these 2 triplets to be diamniotic with a short umbilical cord/body stalk anomaly. After fetal loss a postmortem examination demonstrated that these fetuses were conjoined with a body stalk anomaly/short umbilical cord syndrome with fusion of the coelomic cavities and small bowel (minimally united/conjoined twins). There were dividing amniotic membranes. This case demonstrates the development of an unusual type of conjoined twin with characteristic features. Conjoined fetuses with this pattern have fused small bowel and cloacal anomalies and often diamniotic placentation, when this is recorded. Various terms including minimally united/conjoined omphalopagus/ischiopagus have been used for this characteristic pattern, but this pattern may warrant a specific term. “Diamniotic vitellopagus” may best reflect the pathogenesis of this pattern.
Multinucleated Foreign Body Giant Cells in Placental Membrane
Authors: Sheridan Todd , Askin Frederic B. , Ji Hongxiu
Published: October 2005

We report the pathologic finding of a multinucleated foreign body giant cell reaction to squames and fetal hair in the placental membranes in a 37-week 1-day intrauterine gestation. This reaction appeared to have developed in association with repeated intrauterine procedures performed in the third trimester, including cordocentesis for fetal blood sampling, intrauterine blood transfusion, and amnioreduction for polyhydramnios. This type of reaction most likely was directed to prolonged amniotic fluid leakage that occurred spontaneously or after intrauterine procedures in the second half of the second trimester and the third trimester. Careful examination of the placental membranes and recognition of the foreign body giant cell reaction may provide etiologic insight in cases of unexplained oligohydramnios.
β-Catenin and Met Deregulation in Childhood Hepatoblastomas
Authors: Ranganathan Sarangarajan , Tan Xinping , Monga Satdarshan P. S.
Published: October 2005

Activation of the Wnt/β-catenin and hepatocyte growth factor/Met signaling has been implicated in various tumors. Owing to the cross-talk between these pathways and aberrant redistribution of β-catenin in hepatoblastomas, we examined their status in this tumor. This study examined changes in β-catenin and Met in paired pretreatment and post-treatment hepatoblastoma tissues in relation to their effects on proliferation and target genes such as c-myc and cyclin-D1. In this study we compared proliferation indices, β-catenin staining and its known molecular targets, c-myc and cyclin-D1, and Met, a tyrosine kinase receptor for hepatocyte growth factor in pretreatment and post-treatment specimens. Pretreatment and post-treatment sections from 13 children, ages 11 weeks to 9 years, were analyzed for these markers by immunohistochemistry. All tumors (13 of 13) displayed increased proliferation and β-catenin (cytoplasmic and nuclear) staining in pretreatment biopsies that remained relatively unaffected after treatment. Aberrant Met staining (cytoplasmic) was observed in all pretreatment samples that decreased considerably after treatment in 11 of 13 patients. A significant subset of these tumors showed increased c-myc and cyclin-D1 staining in pretreatment biopsies that decreased after chemotherapy in most cases. β-Catenin redistribution in tumor cells corresponds to proliferation in hepatoblastomas. However, β-catenin nuclear localization remains unaffected in viable hepatoblastoma tissue after chemotherapy. In contrast, Met undergoes a prominent decrease after treatment and thus might be important in pathogenesis of hepatoblastoma.
Light Microscopic, Immunohistochemical, and Ultrastructural Findings in Congenital Fibular Aplasia or Hypoplasia (FAH)
Authors: Hermanns-Sachweh Benita , Stemper Anne , Klosterhalfen Bernd , Senderek Jan , Büttner Reinhard , Weber Michael
Published: October 2005

Congenital aplasia or hypoplasia of the fibula (FAH) is a rare malformation that is defined by a partial or complete absence of the fibular bone. Etiology and pathogenesis are unknown and the precise morphology of the tissue cord replacing the malformed fibula has not been well described. Therefore, tissue cord was examined in 8 patients with FAH. Light microscopic, immunohistochemical, and electron microscopic investigations showed a core of embryonic cartilage with collagen II and VI expressions surrounded by connective tissue. Although collagen II expression is typical for chondroid differentiation, collagen VI reactivity is normally seen in articular cartilage and tendon-like fibrocartilaginous tissue but is absent in hyaline cartilage. Further ultra-structural analyses by electron microscopy supported these findings. The histomorphologic changes correspond to the histologic findings of Papenbrock et al. (2000, Mech Dev 92:113–123) who produced a congenital malformation in transgenic mice that resembled FAH by overexpression of Hox c11.
Telangiectatic Focal Nodular Hyperplasia of the Liver in the Perinatal Period: Case Report
Authors: Okamura Nobuyoshi , Nakadate Hisaya , Ishida Kazuo , Nakahara Saori , Isobe Yoshinori , Ohbu Makoto , Okayasu Isao
Published: October 2005

We report a case of congenital telangiectatic focal nodular hyperplasia, a rare variant form of the disease. The patient was a 2-month-old boy whose parents noticed abdominal distention about 2 weeks after birth, and ultrasonogram revealed a large mass in the liver. He underwent right lobectomy, and gross findings showed an ill-defined mass without any central scar. Histologic findings demonstrated proliferating hepatocytes without atypia arranged in cords of 1- or 2-cell thickness with marked sinusoidal dilatation and extramedullary hematopoiesis. In addition, a significantly increased Ki-67 labeling index in the tumor compared with non-tumor liver cells, and cytogenetic analysis of 23 G-banded metaphase preparations revealed 3 abnormal karyotypes, suggesting hyperplastic or neoplastic features. To the best of our knowledge, the present case is only the third documented case of congenital telangiectatic focal nodular hyperplasia.
Novel DNA markers for rapid, accurate, and cost-effective discrimination of the continental origin of Atlantic salmon (Salmo salar L.)
Authors: Gilbey John , Knox David , O'Sullivan Martha , Verspoor Eric
Published: October 2005

Salmon from geographically representative rivers in North America and Europe were typed for variation at the microsatellite locus SS1 and the mitochondrial DNA ND-1 restriction site 3971, using PCR amplification and agarose-gel electrophoresis. North American salmon showed near-fixation for SS1 alleles between 129 and 135 bp in length and the N mtDNA restriction type, while European salmon near-fixation for SS1 alleles between 183 and 219 bp and the A/D mtDNA type. Based on the observed variant frequencies, using these two markers in combination is predicted to give correct assignment of >99.5% of salmon to continent-of-origin. As both these continental markers can be screened by agarose-gel electrophoresis, their use offers a more rapid, cheaper, and simpler method for accurate assignment of Atlantic salmon to continent-of-origin than do existing methods. These markers can be applied to the identification of salmon in North Atlantic high-seas fisheries, in aquaculture stocks, and in rivers to determine the continent-of-origin of fish-farm escapes.
Assessment of the influence of surgical technique on postoperative pain and wound tenderness in cats following ovariohysterectomy
Authors: Grint Nicola J. , Murison Pamela J. , Coe Richard J. , Pearson Avril E. Waterman
Published: October 2005

Elective ovariohysterectomy was performed on 66 cats. Surgical approach was flank (group F) or midline (group M) allocated by block randomisation. Pre-anaesthetic medication was acepromazine (0.1 mg/kg) via intramuscular injection. Anaesthesia was induced with intravenous thiopentone, and maintained with halothane in 100% oxygen. Carprofen (4 mg/kg) was administered by the subcutaneous route immediately after induction of anaesthesia. Postoperative pain and wound tenderness were assessed at 1, 3, 6, 9, 11–12 and 20–24 h after the end of surgery, and the assessment outcome marked on visual analogue scales (VAS). Intervention analgesia (if pain VAS was >40 mm) was pethidine 4 mg/kg via intramuscular injection. Area under the curve (AUC) for VAS for pain and VAS for wound tenderness for each cat were calculated. AUC for wound tenderness was significantly greater for group F ( P=0.007). There was no significant difference for AUC for pain between the groups. In conclusion, wounds after flank ovariohysterectomy are significantly more tender than after midline ovariohysterectomy in the cat. This indicates that interactive methods, including wound palpation, must be used to assess postoperative pain and the findings should be appropriately weighted in the overall assessment.
Impact of role in the decision to fail: An exploratory study of terminated projects
Authors: Dilts David M. , Pence Ken R.
Published: October 2005

Our research examines factors used by public service personnel and their contractors to reach the decision to terminate a project. Two decision‐making roles are studied: executives, those with the authority to start or cancel a project, and project managers, those who direct the day‐to‐day operations of the project. Our exploratory survey research, an initial step in this topic, suggests that different roles cluster critical termination factors uniquely and use different decision weighting levels on these factors. On a second construct, information gathering actions, such as scanning and interpretation, show an indication of bias, particularly sunk cost bias, and this bias is experienced differently by executives and project managers. Interestingly, the scale of a project, in terms of labor‐hours, calendar time, or budget, does not appear to be related to perception of ‘failure’. The implications for the management of government safety projects are that care must be taken to understand the differing viewpoints of the two types of decision‐makers and that the initial presentation of information concerning a project may influence the perception of a project's outcome. While there are several implications for operations management research, the most critical is that care must be given when surveying “managers” concerning subjective measures of ‘success’ or ‘failure’ as there can be radical perceptual differences by role.
conservation of freshwater and euryhaline elasmobranchs: a review
Authors: martin r. aidan
Published: October 2005

published data on the diversity, life history, ecology, and status of freshwater and euryhaline elasmobranchs was reviewed in the context of anthropogenic threats and principles of conservation biology. at least 171 species of elasmobranch, representing 68 genera and 34 families, are recorded from fresh or estuarine waters. of these, over half are marginal in estuaries, less than one-tenth are euryhaline, and one-fifth are obligate in fresh water. obligate freshwater elasmobranchs are dominated by myliobatoid stingrays, of which two-thirds are potamotrygonids endemic to atlantic drainages of south america. freshwater and euryhaline elasmobranchs adhere to strongly k-selected life histories and feed at high trophic levels, similar to those of their marine relatives. however, freshwater and euryhaline elasmobranchs are also subject to habitat constraints, notably more limited volume and physicochemical variability than the ocean, that may render them more vulnerable than marine elasmobranchs to the effects of human activities. the greatest diversity and abundance of freshwater and euryhaline elasmobranchs occur in tropical countries with enormous and rapidly increasing human populations, notably south america, west africa, and south-east asia. knowledge of the biology, distribution, ecology, and status of freshwater and euryhaline elasmobranchs is frustrated by unresolved taxonomic problems, which are briefly summarized. to clarify selected issues in the conservation of freshwater and euryhaline elasmobranchs, special attention is given to sharks of the genus glyphis, pristids, and potamotrygonids. to foster live release when possible as well as prevent discard of specimens and loss of data, an illustrated key to differentiate carcharhinus from glyphis sharks is provided. obligate freshwater elasmobranchs with limited geographic ranges are deemed most vulnerable to extinction, but euryhaline elasmobranchs that require access to the sea to breed are also at significant risk. based on the foregoing data and principles of conservation biology, suggested action plans for the conservation of freshwater and euryhaline elasmobranchs and the conservation of freshwater habitats are provided.
the potential for cooperative management of elasmobranchs and offshore renewable energy development in uk waters
Authors: gill andrew b. , kimber joel a.
Published: October 2005

the uk government's strategy for reducing greenhouse gas emissions to meet carbon mitigation obligations and the wider aims on sustainable development has provided the impetus for a rapid growth in activity associated with offshore renewable energy, particularly offshore wind farms. recently, consents for offshore renewable energy development (ored) were approved in three strategic areas—the outer thames estuary, the greater wash and the eastern irish sea. the scale of the planned developments means that each will have a large environmental footprint and multiple ored will have a cumulative effect on the environment. here we discuss current understanding of ored construction, operation and decommissioning with regard to the potential interaction with elasmobranchs because of the worrying status of elasmobranch populations within the uk coastal zone. based on the likely interactions between elasmobranchs and ored a framework is proposed which aims to promote cooperative initiatives between elasmobranch conservation management and the offshore renewables industry.
spatial distribution patterns of basking sharks on the european shelf: preliminary comparison of satellite-tag geolocation, survey and public sightings data
Authors: southall e.j. , sims d.w. , metcalfe j.d. , doyle j.i. , fanshawe s. , lacey c. , shrimpton j. , solandt j.-l. , speedie c.d.
Published: October 2005

current concerns about the population levels of the basking shark (cetorhinus maximus) in the north-east atlantic have prompted a need to understand population distribution, habitat preference and centres of abundance. in this study, spatial distribution maps derived from satellite-tag geolocations, boat surveys and public sightings data were compared. the broad distribution patterns revealed by these different methods are similar, but there are considerable differences in density distributions. surface sightings data show high densities, or ‘hotspots’ in the hebridean sea, clyde sea, irish sea and close inshore around devon and cornwall. tag geolocations, in contrast, identified two areas where individuals spent considerable time outside the distributions indicated by surveys and public sightings: the celtic sea and western approaches of the english channel. the reason for this disparity and its implications for population estimates for the species are discussed.
migratory behaviour of the thornback ray, raja clavata, in the southern north sea
Authors: hunter e. , buckley a.a. , stewart c. , metcalfe j.d.
Published: October 2005

although depleted throughout the european continental shelf, the relatively high density of thornback rays raja clavata, in the thames estuary (uk) makes it an important stock centre and potential focus for species management. to describe spatial and temporal distribution, 197 thornback rays were tagged with electronic data storage tags (dsts) and released in the thames estuary in october 1999 and 2000, and 100 rays tagged with conventional tags in 2000. fifty-one per cent of dsts and 48% of conventional tags were returned. fishery-independent estimates of position (‘geolocations’) between the time of release and recapture using the tidal location method were possible using 75 individual data records of between 31 and 423 days. ninety-six per cent of rays were recaptured within the thames estuary. the rays were located in water of 20–35 m depth during the autumn and winter, then migrated into shallower water (<20 m depth) during the spring. fishery-independent analysis of distribution demonstrated that the rays were more widely distributed in the southern north sea during the autumn and winter. the range contracted in spring, when the fish moved into the inner thames estuary. no gross behaviour differences were observed between males and females. displacement and dispersion coefficients calculated from geolocation data demonstrated clear annual cycles, indicative of migration. these movements were not apparent from the mark–recapture data, a fishery-related effect. the extent of migration as determined from experiments with dsts was approximately three times greater than that suggested by conventional tagging data alone.
occurrence of the velvet belly, etmopterus spinax (elasmobranchii: etmopteridae) in angolan waters, south-east atlantic
Authors: zaera diana
Published: October 2005

the presence of velvet belly, etmopterus spinax in angolan waters is confirmed by the capture and examination of 233 specimens caught between 2002 and 2004 on board the rv ‘dr. fridtjof nansen’. morphometric measurements are given.
survival of small-spotted catshark (scyliorhinus canicula) discarded by trawlers in the cantabrian sea
Authors: rodríguez-cabello c. , fernández a. , olaso i. , sánchez f.
Published: October 2005

discards represent a significant percentage of the total catches (up to 35%) in the north of spain trawl fishery. in the cantabrian sea (southern area of the bay of biscay), the estimated average total annual catch of small-spotted catshark (scyliorhinus canicula) is approximately 1500 tn, from which 80% is discarded. several experiments have been carried out in order to estimate the survival-rate of the small-spotted catshark caught by commercial trawlers in this area. the estimate of mean survival-rate from tagging surveys was 90% while from commercial trawlers it was 78%. several factors potentially influencing the survival-rate (sex, length, maximum depth fished, sorting time and trawl duration) were examined. no significant differences in survival-rates were found between males and females, and no strong relationships between survival-rate and depth fished, sorting time or trawl duration were evident. in commercial trawlers survival-rate was not dependent on the fish length.
length at first maturity of two species of lantern sharks (etmopterus spinax and etmopterus pusillus) off southern portugal
Authors: coelho rui , erzini karim
Published: October 2005

etmopterus spinax and etmopterus pusillus are captured in large quantities in some deep-water fisheries along the portuguese coast and are always discarded. specimens were collected from february 2003 to may 2004 from deep-water fisheries and classified as mature or immature. maturity ogives were fitted and size at first maturity estimated for each sex of each species. both species are late maturing, with the maturity sizes varying between 75% and 87% of the maximum observed sizes, depending on species and sex. for both species, females tended to mature at and grow to larger sizes than males. the late maturation of these deep-water shark species makes these populations extremely vulnerable to increasing fishing mortality.
repeated seasonal migration by a thornback ray in the southern north sea
Authors: hunter e. , buckley a.a. , stewart c. , metcalfe j.d.
Published: October 2005

tagged with an electronic data storage tag on 6 october 1999 in the thames estuary (uk), a thornback ray, raja clavata, was recaptured after 504 days at liberty, 276 km north-west of release. the tag recorded 423 days of data. the migration was reconstructed using the tidal location method, and illustrates seasonal migration out of the thames estuary to the central southern north sea during autumn and winter, then a return to the thames to spawn during spring. this is the first direct evidence of repeated seasonal migration outside the area commonly thought of as the species home range, an observation with significant implications regarding the applicability of closure management as a conservation measure for this species.
reproduction of captive raja spp. in the dolfinarium harderwijk
Authors: koop john h.
Published: October 2005

five raja species are displayed in the ‘ray reef’ at dolfinarium harderwijk and, from 1993–2001, 41,772 eggs were laid, of which 39% contained a yolk sac and 3% hatched successfully. different egg-laying periods were distinguished between species. no annual differences in the egg-laying period were observed for raja microocellata, while hatching periods, and thus incubation periods (4.8–7.0 months), differed significantly. no correlation between seawater temperature and incubation time was found.
age and growth in a temperate euryhaline notothenioid, eleginops maclovinus from the falkland islands
Authors: brickle paul , arkhipkin alexander i. , shcherbich zhanna n.
Published: October 2005

falkland islands' mullet (eleginops maclovinus) were aged successfully using whole sagittal otoliths from 1403 individuals. marginal increment analysis indicated that one opaque and one translucent zone were laid down annually. unvalidated daily ring counts confirmed what was thought to be the first translucent zone. the translucent zones were found to form earlier in juveniles than in adults. juveniles over winter in the creeks and inlets whereas adults are more common in deeper inshore waters where there is a one month lag in the minimum winter water-temperature. the maximum observed age was found to be 11 years. the calculated von bertalanffy growth model (lt=124.41(1−e−0.14/year(t-0.01years))) showed that e. maclovinus is a fast-growing fish, growing on average 10.2 cm/year for the first six years of its life.
diet and feeding of the cutlassfish trichiurus lepturus in the subtropical convergence ecosystem of southern brazil
Authors: martins agnaldo s. , haimovici manuel , palacios raul
Published: October 2005

the diet and feeding of the cutlassfish trichiurus lepturus were studied based on analyses of the stomach contents of larvae, juveniles, and adults collected along the continental shelf and shelf break off southern brazil, from the cape of santa marta grande (28°36′s) to chuí (34°45′s). the larvae and pre-juveniles with a total length of <5 cm were found to have fed almost exclusively on calanoid copepods, whereas juveniles (5 to 30 cm) fed on small zooplanktonic crustaceans such as lucifer faxoni and promysys atlantica. on the other hand, sub-adults (30 to 70 cm), fed on euphausiids, mainly euphausia similis, and small fish, mostly anchovy engraulis anchoita. adults (70 to 160 cm) fed on a wide range of larger prey, such as anchovy, sciaenid fish, cephalopods and coastal shrimps, as well as euphausiids. the juveniles and sub-adults fed more intensively than adults during the warm-water season whereas adults fed more intensively during the cold-water season. feeding activity was more intense at night, while cannibalism was more frequent during the warm season, when biological productivity was lower. finally, diet diversity was higher in coastal waters, during the warm season. the abundance of cutlassfish off southern brazil may be explained by the fact that it is adapted to feed on a wide size-range of both pelagic and demersal prey.
embryonic and larval development of the malabar grouper, epinephelus malabaricus (pisces: serranidae)
Authors: leu ming-yih , liou chyng-hwa , fang lee-shing
Published: October 2005

the embryonic and larval development of epinephelus malabaricus are described and illustrated for the first time. fertilized eggs, with a mean diameter of 0.90±0.02 mm and a range from 0.87 to 0.93 mm, were spherical, transparent, buoyant and unpigmented. embryonic development lasted 26 h 30 min at 25.5°c. newly hatched larvae were 1.93±0.04 mm in total length (tl) with 26 (11+15) myomeres and had an oil globule in the ventroposterior area of the yolk sac. three days after hatching (2.76 mm tl), the mouth opened. early larvae had two clusters of well-developed melanophores appearing on the alimentary canal and at the caudal region of the body, and the appearance of xanthophores on the dorsal finfold. nine days after hatching (4.04 mm tl), the buds of the second dorsal and pelvic fin spines had appeared. at 5.41 mm tl, the notochord was slightly flexed, and the hypural bones and caudal fin rays had begun to develop. at 7.39 mm tl, the ratios of the second dorsal and pelvic-fin spine lengths to tl attained their maximums, 52.68% and 48.62%, respectively. at 20.19 mm tl, all fins had the adult complement of rays and spines. by 30.18 mm tl, the body had become red, with five irregular, oblique, dark brown bars visible on the body. the larval habitat shifted from the surface and middle layers to the tank bottom.
wild fish spatial structure in response to presence of fish farms
Authors: giannoulaki m. , machias a. , somarakis s. , karakassis i.
Published: October 2005

acoustic surveys were carried out in three regions of the aegean sea where fish farming zones have been established in order to study the mesoscale effect of fish farms on the spatial structure of wild fish communities. in each area two sites were sampled during may and september. one site was close to the fish-farming zone while the other (reference site), was located in a place with similar topography at a mean distance of 20 nautical miles from the fish-farming zone. geostatistical techniques (omnidirectional and exhaustive variograms) were used to analyse and visualize the spatial structure of the wild fish assemblage in each site. the spatial structure of wild fish aggregations at all three fish farming zones showed consistently a pronounced directionality during both sampling periods, indicating that the wild fish patch was oriented towards a specific direction. this was not observed in the respective reference areas. the observed directionality suggested a response at a mesoscale level of the wild fish biota to the presence of the fish farms in the adjacent coastal area.
calliobdella lophii (hirudinea: piscicolidae) parasitizing white anglerfish lophius piscatorius off the north of spain
Authors: landa jorge , arronte juan c. , abaunza pablo , fariña antonio c.
Published: October 2005

this paper describes the interaction between two species: white anglerfish lophius piscatorius and its specific leech parasite calliobdella lophii off the north of spain. catches of white anglerfish by the spanish gill-net fleet operating in those waters were sampled monthly in 2001. abundance, mean intensity and prevalence were used to analyse infestation level by c. lophii. prevalence of leeches and fish length was significantly correlated. mean intensity was higher on larger white anglerfish. significant differences were found in the presence of leeches by fish length between areas, with higher values in the western part of the studied area. no significant differences were found in the presence of leeches between sexes or seasons.
coordinating perceptually grounded categories through language: a case study for colour
Authors: steels luc , belpaeme tony
Published: October 2005

this article proposes a number of models to examine through which mechanisms a population of autonomous agents could arrive at a repertoire of perceptually grounded categories that is sufficiently shared to allow successful communication. the models are inspired by the main approaches to human categorisation being discussed in the literature: nativism, empiricism, and culturalism. colour is taken as a case study. although we take no stance on which position is to be accepted as final truth with respect to human categorisation and naming, we do point to theoretical constraints that make each position more or less likely and we make clear suggestions on what the best engineering solution would be. specifically, we argue that the collective choice of a shared repertoire must integrate multiple constraints, including constraints coming from communication.
intimations of optimality: extensions of simulation testing of color-language hypotheses
Authors: bimler david
Published: October 2005

by emphasizing that color categories are the collective achievement of a language community, the methodology of steels & belpaeme (s&b) suggests a number of corollaries. it focuses attention on whether a system of categories is optimized to match color experience. if a hypothesis can be operationalized about the nature of the optimality – about how color language becomes standardized – it becomes testable.
language, ecological structure, and across-population sharing
Authors: bódog alexa , háden gábor p. , jakab zoltán , palatinus zsolt
Published: October 2005

we propose a way to achieve across-population sharing within the authors' model in a way that is plausibly in accordance with human evolution, and also a simple way to capture ecological structure. finally, we briefly reflect on the model's scope and limits in modeling linguistic communication.
moral heuristics: rigid rules or flexible inputs in moral deliberation?
Authors: anderson elizabeth
Published: October 2005

sunstein represents moral heuristics as rigid rules that lead us to jump to moral conclusions, and contrasts them with reflective moral deliberation, which he represents as independent of heuristics and capable of supplanting them. following john dewey's psychology of moral judgment, i argue that successful moral deliberation does not supplant moral heuristics but uses them flexibly as inputs to deliberation. many of the flaws in moral judgment that sunstein attributes to heuristics reflect instead the limitations of the deliberative context in which people are asked to render judgments.
cerebral lateralisation, “social constraints,” and coordinated anti-predator responses
Authors: brown culum
Published: October 2005

lateralisation is traditionally viewed by neuroscientists and comparative psychologists from the perspective of the individual; however, for many animals lateralisation evolved in the context of group living. here i discuss the implications of individual lateralisation within the context of the group from an evolutionary ecology perspective, with particular reference to coordinated anti-predator behaviour.