bluuebunny/crossref_metadata_2025 huggingface dataset:
A critical evaluation of peer review via teaching observation within higher education
Authors: Blackmore Jacqueline A.
Published: April 2005

Purpose

To provide a best practice framework for peer review via teaching observation as a method of appraising teaching performance within UK higher education (HE) institutions.

Design/methodology/approach

The paper uses secondary data analysis via the current literature on peer review and peer appraisal, as well as use of primary data obtained via the design, implementation and analysis of semi‐structured interviews with management and teaching staff within the Faculty of Business and Management Science within a fictitiously named Riverbank University.

Findings

Provides a best practice framework for peer review based on the literature, where the case study university benchmarks well against the framework and an insight into the perceptions of teaching staff on the scheme.

Research limitations/implications

The sample of 40 teaching staff was from only one faculty, in one university. Before generalising the findings it would be prudent to widen the research to include a larger sample from more universities across the HE sector in the UK.

Practical implications

The research has massive implications for the UK HE sector if peer review is to be used as a method of assessing teaching performance.

Originality/value

The paper is valuable as a guide to senior management wishing to implement a peer observation scheme within their own institution.
Higher education in a box
Authors: Poch Susan
Published: April 2005

Purpose

The purpose of this paper is to examine how transfer students interact with a higher education setting that is reacting to new state‐mandated accountability goals, and to understand higher education institutions and their environments when faced with new accountability measures. The larger purpose of the study is to develop a grounded theory that helps all players understand the tensions that exist between the state, the universities, and transfer students.

Design/methodology/approach

The paper presents a qualitative study using Bronfenbrenner's ecological theory.

Findings

The paper finds that interactions between the systems played a large role in the transfer students' perceptions of their experiences at a four‐year institution. The universities in this study, and their transfer student policies, reflect an environment that was influenced by and influenced transfer students' perceptions.

Research limitations/implications

To date no research has been found that incorporates the ecological model and higher education institutions. Because of this, it is difficult to determine how effective this model may be for institutions that are wrestling with dilemmas.

Originality/value

The ecological theory used in this qualitative study is a useful tool in understanding the contexts and systems in which transfer students, administrators and state‐mandated accountability goals co‐exist.
Comparative age differences of job satisfaction on faculty at higher education level
Authors: Tu Leafy , Plaisent Michel , Bernard Prosper , Maguiraga Lassana
Published: April 2005

Purpose

The study aims to examine the age differences of job satisfaction between Taiwanese and Chinese higher education faculty.

Design/methodology/approach

The data on job satisfaction were obtained from 194 Taiwanese faculty and 211 Chinese faculty at college levels in one city.

Findings

No statistically significant differences were found for full‐time Taiwanese and Chinese faculty in the overall job satisfaction of age at higher education after educational reforms, but differences exist between countries.

Originality/value

This article applies to strategies on job satisfaction for the current Taiwanese and Chinese faculty at colleges.
Accumulation profiles of lead and cadmium in the edible tissues of Oreochromis aureus during acute exposure
Authors: Allen P.
Published: April 2005

Acute exposure of Oreochromis aureus to cadmium or lead resulted in different tissue accumulation profiles. Trunk kidney accumulated the highest lead concentrations of all tissues analysed after 24‐h or 1‐week exposure to 0.1 mg l–1 lead as PbCl2 while exposure to 0.1 mg l –1 cadmium as CdCl2 for 24 h or 1 week resulted in the highest accumulations of cadmium in the intestine. Caudal muscle consistently accumulated the lowest levels of lead or cadmium after a 1‐week exposure period.
Growth of the clupeid fishes,Stolothrissa tanganicaeandLimnothrissa miodon, in the Zambian waters of Lake Tanganyika
Authors: Kimura S.
Published: April 2005

The age and growth of two endemic Lake Tanganyikan clupeid fishes,Stolothrissa tanganicaeandLimnothrissa miodon, were estimated from analysis of otolith microstructure in specimens collected in Zambian waters from October to December 1990. Both species had relatively clear, concentric otolith increments which were believed to represent daily increments based on their similarity to daily increments found in some marine clupeid species. The growth rates estimated from length‐at‐age data were: forS. tanganicae, Lt= 104·0 (1 – exp (– 0.00512 (t– 5·8))); forL. miodon, Lt= 155.4 (1 – exp (– 0.00236 (t+8.1))). In most cases, the growth parameters obtained from otolith analyses generally agreed with those previously estimated from analyses of length‐frequency distributions.
Body water content over a range of ambient salinities in the sheepshead minnow
Authors: Nordlie F. G. , Wahl W. A. , Binello J. , Haney D. C.
Published: April 2005

Body water content was determined on groups of Cyprinodon variegatus after sequential acclimation to ambient salinities in the range from fresh water to 100%. A multiple linear regression model applied to the data included body mass (M) of individuals and acclimation salinity (S) as independent variables, and body water content (W) as the dependent variable. The model that described the relationship was W(g) = 0·059 + 0·723 M (g)–0001 S (%). Converting values of body water content to percent of wet body mass produced a range of values from 74·5% in fresh water to 72·0% at 100%, only a 2·5% difference in body water content over this wide range of ambient salinities.
Gill raker structure and selective predation on zooplankton by particulate feeding fish
Authors: Langeland A. , Nøst T.
Published: April 2005

The relationship between the gill raker structure of planktivorous fish (number, distance between gill rakers and length) and selective feeding on different species and size classes of zooplankton was studied. Gill raker structure was measured for brown trout Salmo trutta, Arctic charr Salvelinus alpinus, whitefish Coregonus lavaretus, roach Rutilus rutilus, bleak Alburnus alburnus, and three‐spined stickleback Gasterosteus aculeatus. All species are facultative planktivorous fish and occur commonly in Scandinavian lakes. The effect of gill raker structure was studied by comparing prey found in fish stomachs with the availability of zooplankton from several lakes. Gill raker length and distance were significantly correlated with fish length. Although gill raker structure differed among species, all fish species selected the larger zooplankters. The minimum size of cladoceran species found in fish stomachs was much smaller than the distance between gill rakers. Despite great differences in gill raker spacing, the minimum size ingested of Daphnia galeata and Bosmina longispina was similar for all predators. The hypothesis that small zooplankton are strained and retained by the gill rakers in particulate feeding planktivorous fish, particularly in salmonids and roach, is rejected.
Biased underwater visual census biomass estimates for target‐species in tropical reef fisheries
Authors: Jennings S. , Polunin N. V. C.
Published: April 2005

Visual census biomass estimates are compared with yields of three emperor (Lethrinidae) genera from shallow water fished reef habitats and we demonstrate that visual census can consistently underestimate the exploitable biomass of Lethrinus spp.
Origin of a Spanish population of Fundulus heteroclitus inferred by cytochrome b sequence analysis
Authors: Bernardi G. , Fernandez‐Delgado C. , Gomez‐Chiarri M. , Powers D. A.
Published: April 2005

Fundulus heteroclitus in the estuary of the Guadalquivir River in southern Spain competes with a native killifish, Aphanius iberus. Cytochrome b sequence analysis shows that the Spanish individuals are derived from the northern of two possible American populations of F. heteroclitus
Comparison of Bend Stress Relaxation and Tensile Creep of CVD SiC Fibers
Authors: Morscher Gregory N. , Lewinsohn Charles A. , Bakis Charles E. , Tressler Richard E. , Wagner Timothy
Published: April 2005

Three different CVD SiC fibers were tested for bend stress relaxation (BSR) and tensile creep over a wide range of temperatures, times, and stresses. Primary creep was always observed, even for creep strains on the order of 2%. The BSR and tensile creep results were compared using simple linear viscoelastic principles. It was found that BSR results could predict the same time and temperature dependence as tensile creep; however, BSR‐predicted creep strains usually overestimated the magnitude of tensile creep strain. The time, temperature, and stress dependence were determined for all the fibers for the experimental conditions of this study. Some of the primary creep behavior can be explained by load‐sharing effects between the core and the CVD SiC substrate and some microstructural changes; however, the extent of primary creep cannot fully be accounted for from this work.
Twinning‐lnduced Stress and Electric Field Concentrations in Ferroelectric Ceramics
Authors: Zhang Ying , Jiang Qing
Published: April 2005

Experimental investigations suggest that microcracking may be the major cause for the commonly encountered degradation of ferroelectric actuators, namely electric fatigue. It is commonly believed that stress concentration is responsible for the onset of cracking although the quantitative relation between these two events has not been understood completely. It is expected that formation of ferroelectric twins, i.e., 90° domains, can cause severe stress concentration at intersections of domain walls with grain boundaries because of the incompatibility of lattice distortions with grain boundary constraints. This article presents an analysis upon the asymptotic behavior of stress and electric fields near these intersections. The asymptotic analysis is carried out within a framework of electrostatics for deformable continua. Assuming that the electromechanical state in each of the ferroelectric domains is slightly distorted from one of the natural states of the crystal, the authors developed a piecewise linearized model for which concentrations of stress and electric fields correspond to singularities of these fields. The analysis concludes that both the stress and the electric fields exhibit a power‐law singularity; i.e., their magnitudes are proportional to rλ, with r being the radial coordinate originating at the intersecting point and λ being a constant whose value is within the range (–1,0). The examples included show that the severity of concentration depends upon the crystal orientation and the orientations of the domain walls with respect to the grain boundary which they intersect. Considering the microcracks may be generated during the cooling or poling process, the authors have also studied the interaction of ferroelectric twins with preexisting microcracks, both intergranular and transgranular. The analysis indicates that this interaction makes the singularity substantially stronger than the conventional √r‐singularity and hence it suggests that this interaction promotes crack growth.
Phase Equilibria of the SrO–CaO–CuO System at 950°C in 1 atm of Oxygen and at 10 kbar
Authors: George Etienne , Elthon Don , Meen James K.
Published: April 2005

Phase equilibria in the CuO‐rich (≥33% CuO) portion of the SrO–CaO–CuO system have been determined at 950°C in 1 atm of pure oxygen and at 10 kbar (1 bar = 105 Pa). Three solid‐solution series occur under these conditions. There is a complete solid solution between the Ca2CuO3 and Sr2CuO3 endmembers at both 1 atm and 10 kbar, as has been previously noted in experiments conducted in air. Another solid‐solution series extends continuously between SrCuO2 and (Sr0.38Ca0.62)CuO2 in 1 atm of oxygen, but is limited to between SrCuO2 and (Sr0.64Ca0.36)CuO2 at 10 kbar. At 10 kbar, more Ca‐rich phases in this solid‐solution series are not stable, but (Sr0.3Ca0.7)CuO2 and (Sr0.1–0.16Ca0.9–0.84)CuO2 are stable at 1 atm. The third solid‐solution series ranges between Srl4Cu24O38 and (Sr0.41CaO.59)14‐Cu24O38 in 1 atm of oxygen; the Ca‐rich limit of this solid solution changes only slightly to (Sr0.39Ca0.61)14Cu24O38 at 10 kbar.
Characterization of the Firing Schedule for Positive Temperature Coefficient of Resistance BaTiO3
Authors: LaCourse Brian C. , Amarakoon Vasantha R. W.
Published: April 2005

The development of positive temperature coefficient of resistance (PTCR) behavior during the firing procedure of semiconducting BaTiO3 was characterized. The PTCR properties of BaTiO3 were shown to be sensitive to the material's microstructure, liquid‐phase distribution, and extent of grain‐boundary oxidation. The PTCR behavior first became pronounced as the material cooled from the sintering stage at 1350°C to the annealing stage at 1175°C. Within this region, rapid oxidation of the grain boundaries occurred, which resulted in significant formation of charge carrier traps and a potential barrier. The rapid oxidation of the grain boundaries corresponded with the redistribution and solidification of the liquid phases. Once the carrier traps were established, the magnitude and slope of the PTCR jump increased during the annealing and cool‐down stages of the firing procedure because of further oxidation of the grain boundaries.
Shock‐Compaction of Nano‐Sized Diamond Powder, as Examined by Microstructural Analysis
Authors: Kondo Ken‐Ichi , Kukino Satoru , Hirai Hisako
Published: April 2005

Nano‐sized diamond powder, shock‐compacted in the present study, showed neither grain growth nor graphitization, but the compact was fragmented and not strongly consolidated. In contrast, a mixture of the nano‐sized powder and submicrometer‐sized diamond powder consolidated into a disk with 93 % of theoretical density and a Vickers micro‐hardness of 25 GPa also exhibited no grain growth and showed interparticle bonds only among large particles. Although the samples obtained were neither hard nor strong, microstructural analyses and considerations based on the shock‐compaction theories and models clarified issues surrounding the shock‐compaction method of producing nanocrystalline materials. Both the propriety and the limitation of these theories and models are discussed in this paper.
Simple Mathematical Model for the Electrical Conductivity of Highly Porous Ceramics
Authors: Mizusaki Junichiro , Waragai Katsunori , Tsuchiya Soji , Tagawa Hiroaki , Arai Yoshihide , Kuwayama Yuji
Published: April 2005

A novel approach has been proposed to describe the relationship between the conductivity and relative density of highly porous materials. As a first approximation, porous material was represented by a uniaxial string of spheres along the direction of the potential gradient. Then, a string of spheres was remodeled into a rotating body of sine‐wave functions, f(x) = (1 +r0)/2 + [(1 –r0)/2] sin (πx/c) for 0 ≤x < c and f(πx) = (1 +r0)/2 + [(1 –r0)/2] sin {π(x+ 1 − 2c)/(l −c)} for c≤x < 1, where the former represents the shape of a sphere, the latter that of the bottleneck between neighboring spheres, and r0 denotes the ratio of the minimum diameter at the bottleneck to the maximum diameter of the rotating body. It was shown that the calculated relationships reproduced the reported experimental results for the relationship between the porosity and conductivity of La0.5Sr0.5CoO3, BaF2, and (ZrO2)0.9(Y2O3)0.1. The relative conductivity to the bulk material was close to zero at 45–60% relative density, which is the density of green wares. It steeply increased with an increase in the relative density and then gradually approached that of the bulk material.
Formation, Characterization, and Hot Isostatic Pressing of Cr2O3‐Doped ZrO2 (0,3 mol% Y2O3) Prepared by Hydrazine Method
Authors: Hirano Shingo , Yoshinaka Masaru , Hirota Ken , Yamaguchi Osamu
Published: April 2005

In the ZrO2‐Cr2O3 system, metastable t‐ZrO2 solid solutions containing up to 11 mol% Cr2O3 crystallize at low temperatures from amorphous materials prepared by the hydrazine method. The lattice parameter c decreases linearly from 0.5149 to 0.5077 nm with increased Cr2O3 content, whereas the lattice parameter a is a constant value (a= 0.5077 nm) regardless of the starting composition. At higher temperatures, transformation (decomposition) of the solid solutions proceeds in the following way: t(ss)→t(ss) +m+ Cr2O3→m+ Cr2O3. Above 11 mol% Cr2O3 addition, c‐ZrO2 phases are formed in the presence of Cr2O3. The t‐ZrO2 solid solution powders have been characterized for particle size, shape, and surface area. They consist of very fine particles (15–30 nm) showing thin platelike morphology. Dense ZrO2(3Y)‐Cr2O3 composite ceramics (∼99.7% of theoretical) with an average grain size of 0.3 μm have been fabricated by hot isostatic pressing for 2 h at 1400°C and 196 MPa. Their fracture toughness increases with increased Cr2O3 content. The highest KIc value of 9.5 MPa·;m1/2 is achieved in the composite ceramics containing 10 mol% Cr2O3.
Effect of Na2O Additions in the Crystallization of Barium Ferrite from a BaO‐B2O3‐Fe2O3 Glass
Authors: Lee Chung‐Kook , Berta Yolande , Speyer Robert F.
Published: April 2005

A glass crystallization method was utilized to synthesize nanosized BaO‐6Fe2O3 platelets from a 0.412BaO‐0.258B2O3‐0.330Fe2O3 batch composition. Quenched ribbons were inhomogeneous, showing microclustering and ∼1 μm hematite crystals. Na2O substitutions for BaO greatly enhanced the glass‐forming tendency of quenched ribbons, though quenched‐in ∼0.5 μm barium ferrite crystals were infrequently present. The improved homogeneity with Na2O substitution was attributed to lower vapor pressure of BaO during batch melting, which increased its retention in the as‐quenched ribbons. Quantities of BaO equal to or in excess of Fe2O3 allowed iron ions to adopt stable network positions in the glass melt. With Na2O substitution, devitrification of dispersed ∼40 nm barium ferrite particles from phase‐separated regions occurred after secondary heat treatment. 5 mol% Na2O batch substitution showed the lowest crystallinity in the as‐quenched ribbons, and the highest crystallinity after secondary heat treatment. After optimum devitrification, the maximum values of saturation magnetization and coercivity were 21.22 emu/g and 2.82 kOe, respectively.
Scanning Acoustic Microscopy of SCS‐6 Silicon Carbide Fiber
Authors: Sathish Shamachary , Cantrell John H. , Yost William T.
Published: April 2005

Scanning acoustic microscopy of SCS‐6 silicon carbide fiber reveals large radial variations in acoustic reflectivity associated with the chemical composition and microstructure of a given fiber region. Rayleigh wave fringe patterns observed in each of five subregions are used to calculate the average Young modulus of that subregion. The Young modulus is found to increase monotonically from 40 GPa in the carbon core to a value of 413 GPa in the stoichiometric SiC region. The effective Young modulus of the fiber as a whole is estimated from the moduli of the individual regions and it is compared with mechanical measurements reported in the literature.
Hydrothermal Cement/Metal Interfaces
Authors: Sugama Toshifumi , Baldwin Stephanie
Published: April 2005

We investigated the adherence of two cementitious materials, calcium phosphate cement (CPC) and silica flour‐filled class G cement (CGC), to metal substrates, such as cold‐rolled steel (CRS), stainless steel (SS), electroplated zinc‐coated steel (EZS), and zinc phosphate‐coated steel (ZPS) after autoclaving at 200°C. In CPC/metal joints, the γ‐AlOOH phase, which segregated from the hydroxyapatite phase of the CPC matrix, was preferentially precipitated on the CRS and SS surfaces and also mixed with the reaction products formed at the interfaces between CPC and EZS or ZPS. Precipitation of γ‐AlOOH caused the formation of a weak boundary layer at the interfacial transition zones, thereby resulting in a low shear‐bond strength. Although CGC accelerated the rate of corrosion of CRS and SS surfaces, the growth of Fe2O3 clusters, formed as the corrosion products of metals at interfaces, aided the anchoring effect of xonotlite crystals as the major phase of CGC matrix, thereby conferring a high shear‐bond strength. The EZS and ZPS surfaces were susceptible to alkali dissolution caused by the attack of the high‐pH interstitial fluid of CGC pastes to the Zn and zinc phosphate coatings. Thus, the bond strengths of the CGC/EZS and /ZPS joints were lower than those of the joints made with CRS and SS.
Reaction‐Bonded Mullite/Zirconia Composites
Authors: Lathabai Srinivasarao , Hay David G. , Wagner Florian , Claussen Nils
Published: April 2005

The feasibility of fabricating dense, low‐shrinkage, mullite/ ZrO2 composites based on the reaction bonding of alumina (RBAO) process and the reaction sintering of zircon is examined. Compacts pressed from an attrition‐milled powder mixture of Al, A12O3 and zircon were heated in air according to a two‐step heating cycle. The phase evolution and microstructural development during reaction bonding were traced by X‐ray diffraction, nuclear magnetic resonance, and scanning electron microscopy on samples extracted from various points along the heating cycle. It is seen that, as in conventional RBAO, AI oxidizes to γ‐Al2O3 which then transforms to α‐AI2O3 between 1100° and 1200°C. The zircon dissociation commences at ∼1400°C and is practically complete by 1500°C. Mullite enriched in Al2O3 forms initially, but 3:2 stoichiometry is attained in the final product which consists of mullite, t‐ and m‐ZrO2, and residual α‐AI2O3. The flexure strength of the composite is superior to that of pure mullite, and ∼80% of the strength is retained up to 1200°C. Although there was no toughness enhancement relative to mullite, this should be achievable by optimizing the fabrication procedure.
Structural Role of Aluminum Ions in Sodium Aluminophosphate Glasses
Authors: Yan Yingchao , Faber Anne Jans , de Waal Henk
Published: April 2005

Infrared OH absorption spectra were measured for a series of sodium aluminophosphate glasses. The absorption spectrum appears to be dependent on both alumina content and overall O/P ratio. The latter dependency cannot be explained by the conventional interpretation of the structural role of Al ions. Based on the latest studies on the role of Al ions in the phosphate glass, the influence of Al ions on the OH infared absorption spectrum is examined and explained.
Challenges in developing and implementing ecological standards for geomorphic river restoration projects: a practitioner's response to Palmer et al. (2005)
Authors: GILLILAN S. , BOYD K. , HOITSMA T. , KAUFFMAN M.
Published: April 2005

The authors of ‘Standards for ecologically successful restoration’ (Palmer et al. 2005) are commended for clearly articulating and discussing the nuances of establishing ecological standards in river restoration practice. We agree that there is a need for better and more thoughtful standards to elevate the practice of river restoration to a science of restoration. As practitioners of fluvial restoration, and students of the sciences of geomorphology, hydrology, ecology and plant sciences, we offer our experiences and observations, noting that the desire to achieve ecologically effective project outcomes is not new. We agree that there are valid questions regarding the application of the term ‘restoration’ to projects with minimal ecological benefits.

We also concur that guiding image development is critical to project success. However, we note that well‐intentioned projects often drift from having initially sound restoration objectives to ultimately providing reduced ecological benefit. Our observations suggest that this phenomenon can be attributed to risk aversion and the progressive incorporation of rigid engineered elements. We term this project hardening, where natural channel boundary evolution and change (deformability) is progressively sacrificed. This artificially constrains natural fluvial dynamics and associated ecological function.

We agree that meaningful pre‐ and post‐monitoring programmes are essential to understanding project success. We encourage the academic community to make relevant data sets available to facilitate the evolution of restoration science. It is appropriate for sponsoring agencies to require the collection of these data.

Synthesis and applications. As practitioners we suggest that more interaction with ecologists and the larger academic community is necessary so that practical experience is communicated and integrated into the emerging science of restoration. While this interaction will advance the common goal of implementing more ecologically effective projects, we also note that project participants outside the scientific community must also appreciate the challenges a project faces in meeting higher standards. These challenges are not insignificant and include convincing project sponsors, practitioners and regulators of the need for standards in project generation, implementation and monitoring on a project‐by‐project basis.
Paternal alleles enhance female reproductive success in tropical pythons
Authors: MADSEN THOMAS , UJVARI BEATA , OLSSON MATS , SHINE RICHARD
Published: April 2005

The conventional view that female reproductive success is unlikely to benefit from multiple mating has come under strong challenge in recent years. In the present study, we demonstrate that the time wild‐caught reproductive female water pythons (Liasis fuscus) spent in the laboratory prior to oviposition affected both hatching success and the number of male microsatellite alleles detected in the broods. A negative correlation between time in captivity and number of male alleles observed in the broods suggests that reduced hatching success was most likely not caused by environmental factors such as nonoptimal temperatures, but rather by restricted mating opportunities. Maternal nutritional status and mean hatchling mass did not affect brood viability. However, our results revealed a positive correlation between number of male microsatellite alleles observed in the broods and hatching success, suggesting that increased paternal genetic variability enhanced female reproductive success. As microsatellite loci are unlikely to be direct targets of selection, we suggest that variability at these loci may cosegregate with other polymorphic genes directly linked to fitness.
Genetic variation in the Desert Springsnail (Tryonia porrecta): implications for reproductive mode and dispersal
Authors: HERSHLER R. , MULVEY M. , LIU H.‐P.
Published: April 2005

Allozymes and mitochondrial cytochrome c oxidase subunit I (mtCOI) sequences were analysed to determine whether populations of the western North American gastropod Tryonia porrecta (from California, Nevada, Utah, and northwest Mexico) are strongly differentiated in accordance with traditional interpretation of regional fauna as ancient relicts inhabiting isolated fragments of late Tertiary palaeodrainages. These data were also used to assess whether this species, for which males have not been recorded, is a rare example of a molluscan parthenogen. Both data sets strongly supported monophyly of T. porrecta populations. Five of the nine sampled populations consisted of a single monoallelic allozyme genotype while the others contained two to 10 distinct genotypes. Allozymic data for genetically diverse Utah populations provided evidence of clonal and sexual reproduction. mtCOI haplotypes of T. porrecta formed two subgroups which differed by 1.99–2.60%. The common haplotype was found in seven populations with rare haplotypes observed in single populations. Based on these results and an available mtCOI molecular clock for related hydrobiid snails, T. porrecta is interpreted as a primarily parthenogenetic species that undergoes occasional sexual reproduction and has accumulated substantial diversity following its mid‐Pliocene to mid‐Pleistocene origin. Our results also suggest that the distribution of present‐day populations of these gill‐breathing snails did not result from fragmentation of an ancient, well‐integrated drainage but instead reflects overland colonization of habitats which only recently became available following desiccation of late Quaternary pluvial lakes.
The effects of habitat fragmentation via forestry plantation establishment on spatial genotypic structure in the small marsupial carnivore, Antechinus agilis
Authors: BANKS S. C. , LINDENMAYER D. B. , WARD S. J. , TAYLOR A. C.
Published: April 2005

Dispersal is an important influence on species’ distributions, patch colonization and population persistence in fragmented habitat. We studied the impacts of habitat fragmentation resulting from establishment of an exotic pine plantation on dispersal of the marsupial carnivore, Antechinus agilis. We applied spatial analyses of individual multilocus microsatellite genotypes and mitochondrial haplotypes to study patterns of gene flow in fragmented habitat and natural habitat ‘control’ areas, and how this is affected by the spatial dispersion of habitat patches, the presence of corridors and a ‘mainland’ source of migrants. Spatial analysis of molecular variance and partial Mantel tests confirmed the absence of cryptic barriers to gene flow in continuous habitat, which if present would confound the comparison of genetic structures in fragmented vs. unfragmented habitats. Spatial genotypic structure suggested that although dispersal was male‐biased in both habitat types, fragmentation restricted dispersal of males more than that of females and the degree of restriction of male dispersal was dependent on the geographical isolation of the patch. The scale of positive genotypic structure in fragmented habitat was restricted to the two closest patches for females and the three closest patches for males. Our results provide evidence for significantly increased gene flow through habitat corridors relative to that across the matrix and for significantly lower gene flow between ‘mainland’ unfragmented habitat and habitat patches relative to that within either habitat type, suggesting a behavioural barrier to crossing habitat interfaces.
Mating patterns, pollen dispersal, and the ecological maternal neighbourhood in a Prunus mahaleb L. population
Authors: GARCÍA C. , ARROY J. M. , GODOY J. A. , JORDANO P.
Published: April 2005

Gender polymorphism, plant–animal interactions, and environmental heterogeneity are the three important sources of variation in mating system and pollen dispersal patterns. We used progeny arrays and paternity analysis to assess the effects of gender type and density level on variation in mating patterns within a highly isolated population of Prunus mahaleb, a gynodioecious species. All the adult trees in the population were sampled and located. The direct estimate of long‐distance insect‐mediated pollination events was low (< 10%). Gender expression deeply influenced the mating system, decreasing the outcrossing rates (tm) and the pollen pool diversity in hermaphrodite trees. Long intermate distances (> 250 m) were significantly more frequent among female mother trees. Variation in local tree density also affected pollen pool diversity and intermate distance, with a higher effective number of fathers (ke) and longer intermate distances for female trees in low‐density patches. A canonical correlation analysis showed significant correlations between mating variables and the maternal ecological neighbourhood. Only the first canonical variable was significant and explained 78% of variation. Outcrossing rates tended to decrease, and the relatedness among the fathers tended to increase, when mother trees grew in dense patches with high cover of other woody species and taller vegetation away from the pine forest edge. We highlight the relevance of considering maternal ecological neighbourhood effects on mating system and gene flow studies as maternal trees act simultaneously as receptors of pollen and as sources of the seeds to be dispersed.
Comparative analysis of population genetic structure in Athyrium distentifolium (Pteridophyta) using AFLPs and SSRs from anonymous and transcribed gene regions
Authors: WOODHEAD M. , RUSSELL J. , SQUIRRELL J. , HOLLINGSWORTH P. M. , MACKENZIE K. , GIBBY M. , POWELL W.
Published: April 2005

To examine the performance and information content of different marker systems, comparative assessment of population genetic diversity was undertaken in nine populations of Athyrium distentifolium using nine genomic and 10 expressed sequence tag (EST) microsatellite (SSR) loci, and 265 amplified fragment length polymorphism (AFLP) loci from two primer combinations. In range‐wide comparisons (European vs. North American populations), the EST‐SSR loci showed more reliable amplification and produced more easily scorable bands than genomic simple sequence repeats (SSRs). Genomic SSRs showed significantly higher levels of allelic diversity than EST‐SSRs, but there was a significant correlation in the rank order of population diversities revealed by both marker types. When AFLPs, genomic SSRs, and EST‐SSRs are considered, comparisons of different population diversity metrics/markers revealed a mixture of significant and nonsignificant rank–order correlations. However, no hard incongruence was detected (in no pairwise comparison of populations did different marker systems or metrics detect opposingly significant different amounts of variation). Comparable population pairwise estimates of FST were obtained for all marker types, but whilst absolute values for genomic and EST‐SSRs were very similar (FST = 0.355 and 0.342, respectively), differentiation was consistently higher for AFLPs in pairwise and global comparisons (global AFLP FST = 0.496). The two AFLP primer combinations outperformed 18 SSR loci in assignment tests and discriminatory power in phenetic cluster analyses. The results from marker comparisons on A. distentifolium are discussed in the context of the few other studies on natural plant populations comparing microsatellite and AFLP variability.
Metastasizing Seminal Vesicle Adenocarcinoma in a Wistar Rat
Authors: Teredesai A. , Wöhrmann T.
Published: April 2005

An adenocarcinoma in the seminal vesicles of a 15‐month‐old male Wistar rat from a 30‐month inhalation study is described. The rat was killed because of cachexia, apathy and a large palpable mass in the abdominal cavity. Macroscopic examination of the abdominal cavity revealed a 3.8 cm × 3.2 cm yellow‐grey to pink mass, firm to soft in consistency. The cut section revealed cystic spaces. Histologically, the mass consisted of epithelial cells arranged in glandular and solid patterns with abundant amounts of connective tissue. Epithelial tumour cells were round‐to‐cylindrical with round‐to‐oval basophilic nuclei and one or two prominent nucleoli and a distinct eosinophilic cytoplasm. The glandular structure contained clusters of macrophages in their lumen with eosinophilic cytoplasm and indented nuclei. Extensive necrosis and reactive inflammation were present. The histological features of the small nodules in the pancreas and on the surface of the liver, rectum and urinary bladder resembled those of the primary tumour in the seminal vesicles. Based on these criteria, the neoplasm (mass) was diagnosed as an adenocarcinoma of the seminal vesicles. The immunohistological examination confirmed the diagnosis, i.e. immunostaining was positive for cytokeratins (4, 7, 14, 15, 18, and 19), vimentin, PCNA, and ED1.
Systemic AA‐amyloidosis in a European Wild Boar (Sus scrofa) Suffering from Generalized Tuberculosis
Authors: Segalés J. , Vicente J. , Luján L. , Toussaint M. J. M. , Gruys E. , Gortázar C.
Published: April 2005

An adult female wild boar (Sus scrofa) was found moribund in Cabañeros National Park (central Spain). The animal had a markedly emaciated carcass, with body weight of 25.9 kg. At necropsy, most of the parenchymatous organs had widespread variably sized granulomas. Generalized tuberculosis was confirmed by PCR detection of Mycobacterium bovis in the mandibular lymph node. Large amounts of a hyaline, pale eosinophilic material were observed in liver, kidney and intestine. Congo red staining and green birefringence identified amyloid, which was further classified as AA type based on immunohistochemical results. It is speculated that the abundant serum amyloid A derivatives deposited in the tissues as AA‐amyloid may be associated with the generalized tuberculosis. This is the first report of amyloidosis in the European wild boar.
Phylogeny of the Brachystomellidae (Collembola) — were the mandibles ancestrally absent and did they re‐appear in this family?
Authors: Najt Judith , Weiner Wanda M. , Grandcolas Philippe
Published: April 2005

A phylogenetic study was carried out on the family Brachystomellidae, which was found to be monophyletic. The generaBrachystomellaandFolsomiellawere polyphyletic.Folsomiella nothofagutaliswas removed fromFolsomiellaand placed inNeorganella. The analysis showed that mandibles were ancestrally absent in this group and then re‐appeared later inProbrachystomellides nicolaii.
Awareness and use of smoking cessation treatments among diabetic patients
Authors: Gill G. V. , Morgan C. , MacFarlane I. A.
Published: April 2005

Aims  To investigate awareness of pharmacotherapeutic aids to smoking cessation in diabetic cigarette smokers.

Methods  A structured questionnaire‐based interview was held by a research nurse individually with consecutively attending cigarette smokers.

Results  Of 597 diabetic patients attending a routine clinic, 100 (17%) were current cigarette smokers. Mean (± sd) age was 58 ± 11 years, 58% were male, and 96% Type 2 diabetic patients. Mean daily cigarette consumption was 16/day, for a mean duration of 35 years. There were 34% who had never heard of nicotine replacement therapy (NRT), and of those who had, only 49% considered it safe with diabetes. Bupropion (Zyban) was unknown to 46%, and of those who knew of it, 39% thought it unsafe in diabetic patients. Only 31% of the group had been previously offered NRT, and 14% bupropion. The NHS Quitline was known of by 84%, but only 8% had used it.

Conclusions  Cigarette smokers with diabetes have poor uptake, awareness and knowledge of NRT and bupropion as aids to smoking cessation. They comprise a high‐risk group, for large and small vessel disease, and these findings are therefore of concern. More active education and support for these patients by medical and nursing staff is needed.
Rights and Rhetoric: The Politics of Asylum and Human Rights Culture in the United Kingdom
Authors: Chakrabarti Shami
Published: April 2005

No assessment of the state of human rights today could be complete without some consideration of the situation of asylum seekers and the political trends behind it. Four years after the implementation of the 1998 Act, asylum seekers are perhaps more denigrated in rhetoric and harsh practice than they were even before the first promise that rights would be ‘brought home’ for all ‘people’ in the United Kingdom. This piece looks at the undermining of the very concept of asylum, dehumanizing policies such as forced destitution, and attacks on access to legal process for those making asylum claims. It goes on to consider judicial attempts at coping with the arena in which high politics and fundamental rights seem in greatest tension. Finally it considers potential implications for the broader aspiration of building a human rights culture in this country.
Constitutional Reform, the Lord Chancellor, and Human Rights: The Battle of Form and Substance
Authors: Smith Roger
Published: April 2005

This article examines the impact of the Human Rights Act on the government's constitutional proposals for reform of the role of the Lord Chancellor and the appointment of the judiciary. It also looks at the uncertain acceptance of a ‘human rights’ culture by the department charged with lead responsibility for its implementation. It concludes that the government went further than was required in reforming the role of the Lord Chancellor. As a consequence, considerable ‐ and possibly undue – weight now hangs on the enlarged role of the Lord Chief Justice. Meanwhile, the Department of Constitutional Affairs and its ministers have rejected the ‘rule of law’ brief of the Lord Chancellor without clarity as to where such responsibilities might now be adequately located within government.
High current, high current density field emitter array cathodes
Authors: Schwoebel P. R. , Spindt C. A. , Holland C. E.
Published: April 2005

Microfabricated field emitters have shown the potential for very high current densities (>100A∕cm2) and total emission currents (>1A). However, realizing this potential has been elusive, primarily because these cathodes exhibit insufficient emission uniformity over an emitter array. In this article we report the development of an in situ processing method based on emitter tip self-heating during operation that is shown to improve emission uniformity between emitter tips. Two tips differing in emission current by three orders of magnitude for a given voltage as fabricated are shown to be essentially identical in their emission characteristics after controlled pulsing to very high emission current. When the method was applied to a 50 000 tip array, it produced 300 mA of emission (40A∕cm2). The experimental arrangement prevented advancing to higher emission levels due to space charge limitations. It is expected that 1 A of emission at ∼100A∕cm2 is possible with appropriate modifications to the experimental apparatus.
Pulsed field emitted current from different commercial samples in the purpose of a free electron laser application
Authors: Ganter R. , Li K. , Dehler M. , Gobrecht J. , Rivkin L. , Wrulich A.
Published: April 2005

The development of an electron gun with the lowest possible emittance would help reduce the total length and cost of a free electron laser. Recent progress in vacuum microelectronics makes field emitter tips an attractive technology to explore for high brightness electron sources. In order to be a good candidate for a low emittance gun, field emission cathodes must provide at least the peak current, stability, and homogeneity of current state of the art electron sources. In this article, we report on current voltage measurements of commercially available field emitter samples in both continuous and pulsed mode. Pulsed electron emission is of particular interest for a free electron laser application. As mentioned by other authors [F. Charbonnier, Appl. Surf. Sci. 94/95, 26 (1996); P. R. Schwoebol et al., J. Vac. Sci. Technol B 19, 980 (2001)], higher peak current and more stable emission can be achieved when using short square voltage pulses at low frequency. We present maximum peak currents achieved with 100 ns long voltage pulses at low frequency (50 Hz). In such a pulsed mode, the risk of excessive heating and cathode damaging is considerably reduced.
Diffusion of dopants in highly (∼1020cm−3) n- and p-doped GaSb-based materials
Authors: Dier Oliver , Grau Markus , Lauer Christian , Lin Chun , Amann Markus-Christian
Published: April 2005

Diffusion of dopants at high doping concentrations (∼1020cm−3) of GaSb, GaInAsSb, and InAsSb grown in a molecular beam epitaxy system and doped with silicon, beryllium, and tellurium were investigated. The electrically active doping concentration for each material was determined by van der Pauw measurements, while the doping profiles were measured by secondary-ion-mass spectroscopy. The samples were annealed to analyze the diffusion behavior. Two different growth techniques to achieve high doping levels were compared: δ dopings and deposition with reduced growth rate. The diffusion of Be in InAsSb:Be could not be prevented, neither by a low growth rate nor by intermediate GaSb spacers. A strong diffusion of Be and Te was found for δ-doped samples in InAsSb, whereas in slowly grown material the diffusion can be limited for Te as dopant.
Fabrication and characterization of p-type silicon field-emitter arrays for lithography
Authors: Teepen T. F. , van Veen A. H. V. , van’t Spijker H. , Steenbrink S. W. H. K. , van Zuuk A. , Heerkens C. Th. H. , Wieland M. J. , van Druten N. J. , Kruit P.
Published: April 2005

p -doped silicon field emitters were studied experimentally to assess their usefulness in multibeam electron lithography. Both individual emitters and emitter arrays were fabricated from single crystal Si wafers with several doping levels. Current-voltage curves were measured for different temperatures and illumination conditions. The typical plateaus in the I-V curves and the sensitivity to light known from the literature were reproduced. Stability measurements showed a very stable total emission current even while the angular emission distribution fluctuated strongly, giving unstable currents in apertured beams. Measured light response times varied between 34 ns and 20 μs, depending on experimental conditions. It was found that in the plateau of the I-V curve, the energy of the electrons shifts over up to 100 eV when changing the extraction voltage over a few kilovolts. In operation, when the current is stable, the energy shift is rather unstable. The experimental results are discussed within a model of the emission process involving an induced p-n junction inside the tip. The conclusion is that p-doped silicon field emitters are not particularly useful for applications in electron beam lithography.
Transistor characteristics of thermal chemical vapor deposition carbon nanotubes field emission triode
Authors: Wong Y. M. , Kang W. P. , Davidson J. L. , Hofmeister W. , Wei S. , Huang J. H.
Published: April 2005

A study of thermal chemical vapor deposition (CVD) grown carbon nanotubes (CNTs) field emitters in a triode amplifier configuration is reported. The CNT transistor characteristics were examined by integrating gate and anode with CNT cathode in two structural forms, utilizing a TEM grid (transmission electron microscope specimen holder) as the gate electrode and a micropatterned CNT with self-aligned gate. The TEM-grid CNT triode displayed clearly gate-controlled current modulation behavior with distinct cutoff, linear, and saturation regions, and a reasonable gate turn-on field of ∼5.4V∕μm despite a large cathode-gate spacing of ∼120μm. The field emission result established the basic transistor characteristics of CNTs in a triode configuration. A CNT triode construct with a self-aligned gated fabrication technique was also developed to realize a monolithic triode structure with shorter gate-cathode spacing, lowering gate voltage, and enhancing emission current. The triode exhibited a significantly lower gate turn-on voltage of ∼40V, and gate-controlled modulation of the emission current. An anode current density of ∼30mA∕cm2 was achieved at a gate voltage of ∼80V and an anode voltage of ∼200V. The dc characteristics for both of the CNT triodes were investigated, including Ia versus Va for different Vg. Moreover, dc parameters such as transconductance, amplification factors, and anode resistance of the triode amplifier were determined. The CNT triodes exhibited useful amplification factor and high output impedance.