bluuebunny/crossref_metadata_2025 huggingface dataset:
Expectant Mothers and Absent Fathers: Paid Maternity Leave in Australia
Authors: Ainsworth Susan , Cutcher Leanne
Published: June 2008

In this article we explore how the reluctance to introduce a national paid maternity leave scheme in Australia reflects gendered norms and constructions of parenthood and work. We report on the findings of a study of selected media texts that show how the public discourse that surrounded proposals to introduce such a scheme exhibited deep‐seated resistance to women who combine motherhood with continued attachment to the paid workforce. Using a multi‐modal approach to discourse analysis, we show how gender and maternity are constructed using cultural and historical discursive resources that reinforce a conservative national identity. By focusing on what is both absent and present in the media texts we show how ‘actual fathers’ are rendered invisible and the space filled by the government as ‘symbolic fathers’ impregnating a production line of maternal citizens.
Allen Forte in Music Analysis
Authors: Whittall Arnold
Published: June 2008

This article explores the engagement of an American music theorist with a British journal. Music Analysis excludes the word ‘theory’ from its title to avoid confusion with American journals. But many American theorists have welcomed the alternative it represents, and of these Allen Forte is pre‐eminent. His contributions began with Vol. 2/iii (October 1983) and have continued through to the present issue. As this survey suggests, those contributions which are transcripts of spoken presentations emphasise that analysis is not just abstraction but ‘a human thing’. Yet, whether Forte is writing primarily about a topic such as pitch‐class set theory or about admired composers – Musorgsky, Debussy, Messiaen – he offers a distinctive blend of general and particular, placing compositional specifics within wider perspectives which invariably stimulate the reader not just to think but to listen, and re‐listen.
Bird's‐Eye Views of the Musical Surface: Methods for Systematic Pitch‐Class Set Analysis
Authors: Huovinen Erkki , Tenkanen Atte
Published: June 2008

This study presents a series of methods for the analysis of the average characteristics of pitch‐class material on the surface level of musical works. The methods rely on so‐called tail segmentation, the partitioning of a musical work into a large number of overlapping pitch‐class sets of equal cardinality. The resulting data can be used as a means of scanning a piece of music in order to detect changes in the local prevalence of some chosen pitch class–related feature. For example, scanning the musical surface for each individual interval class in turn results in a ‘stretched interval‐class vector’ represented by six curves. In another application termed ‘comparison set analysis’, similarity measures for set classes are used to detect similarities with respect to some chosen set class. One may thus measure local changes in, for example, the relative degree of ‘diatonicism’ within a piece of music. Alternatively, one may compare whole corpuses of compositions in terms of their overall surface similarity with respect to a chosen comparison set. In such methods of systematic pitch‐class set analysis, the focus is shifted from identifying structurally important pitch sets or pitch‐class sets to measuring selected properties within the set of all locally available pitch‐class sets.
The Structuring of Tonal Space in Webern's Six Bagatelles for String Quartet, Op. 9
Authors: Davies Benjamin K.
Published: June 2008

For reasons of chronology and style, Webern's Six Bagatelles for String Quartet, Op. 9 are generally understood to have been composed in an unsystematic, intuitive fashion. The present study seeks to question this assumption, suggesting that these short pieces in fact employ a specific approach to pitch grammar involving the consistent deployment of chromatic wedge structures. This technique, termed the structuring of tonal space, serves to explain note‐to‐note processes as well as aspects of larger‐scale formal design.
Impact of Training on Cognitive Representation of Challenging Behaviour in Staff Working with Adults with Intellectual Disabilities
Authors: Campbell Martin , Hogg James
Published: June 2008

Background  Cognitive representations of challenging behaviour among staff may influence therapeutic outcomes. This study looked at how cognitive dimensions of Identity, Cause, Consequences, Emotional Reaction and Treatment/Control are affected by training.

Materials and Methods  A theoretically derived questionnaire was used to measure the impact of an accredited training course. There were two experimental designs: a longitudinal design using participants as their own controls for repeated measures, and a comparative subjects design. All participants were staff working in statutory and voluntary care services.

Results  The experimental group outperformed the two control groups by more than would be expected, on the basis of pre‐testing, on two of the five dimension measures, Cause and Treatment/Control.

Conclusions  It is important to evaluate outcomes of staff training that seeks to improve staff interactions in line with evidence‐based practice. Changes in staff cognitive representation of challenging behaviour, as a result of training may be multi‐dimensional.
Agricultural intensification and farmland birds: new insights from a central European country
Authors: REIF JIŘÍ , VOŘÍŠEK PETR , Š?ASTNÝ KAREL , BEJČEK VLADIMÍR , PETR JIŘÍ
Published: June 2008

The relationship between agricultural intensification and a decline in farmland bird populations is well documented in Europe, but the results are mostly based on data from the western part of the continent. In the former socialist eastern and central European countries, political changes around 1990 resulted in a steep decline in the intensity of agriculture. Therefore, one would expect populations of farmland birds to have recovered under these conditions of lower agricultural intensity. We explored population trends of 19 farmland bird species in the Czech Republic between 1982 and 2003 using data from a large‐scale monitoring scheme, and, additionally, we looked for relationships between such population changes and a number of variables describing the temporal development of Czech agriculture. Most farmland species declined during the focal period, and this decline was steepest in farmland specialists (Northern Lapwing Vanellus vanellus, Skylark Alauda arvensis, Linnet Carduelis cannabina and Yellowhammer Emberiza citrinella). Although the intensity of agriculture was lower after than before 1990, the overall decline continued in most farmland bird species, albeit at a slower rate. The correlations between agricultural intensity and farmland bird decline showed opposite patterns to that found in other European studies, because bird populations were highest in years with the most intensive agriculture. We speculate that this pattern could have resulted from the impact of different driving forces causing farmland bird decline in different periods. The high intensity of agriculture could have caused the decline of the originally abundant populations before 1990. After 1990, the decreasing area of arable land could be the most important factor resulting in the continued decline of farmland bird populations. Our results demonstrate that the drivers of farmland bird population changes could differ across Europe, and thus investigations into the effect of farmland management in different parts of the continent are urgently required.
Plasticity of moult and breeding schedules in migratory European StonechatsSaxicola rubicola
Authors: FLINKS HEINER , HELM BARBARA , ROTHERY PETER
Published: June 2008

Timing is crucial in seasonal environments. Passerine birds typically use a combination of physiological mechanisms and environmental cues to ensure that breeding, moult and migration occur without major temporal overlap and under the most favourable conditions. However, late in the breeding season some individuals initiate additional clutches , whereas others initiate moult. Such alternative strategies are thought to reflect trade‐offs between reproductive benefits and timely investment in maintenance and survival. The degree of seasonal plasticity differs between species, depending on the mechanisms that govern their annual routine. Migrants are generally under pressure to complete breeding and moult before the autumn departure and often show little plasticity. We studied seasonal plasticity of breeding and moult schedules in the European StonechatSaxicola rubicola.This species, an obligate short‐distance migrant in Central Europe, sometimes initiates late clutches after typically at least two earlier breeding attempts. Based on life‐history theory and on observations in captivity, which revealed photoperiodic regulation of breeding and moult, we predicted relatively little seasonal plasticity in Stonechats. We further predicted that reproductive gains of late breeders should be offset by reduced survival. These predictions were tested on long‐term field data, using Underhill–Zucchini models to estimate moult. Late breeding occurred inc.40% of pairs and increased their reproductive success by a third. Both sexes modified moult timing but in different ways. Late breeding females postponed moult approximately until chick independence without compensating for delay by faster moult. Males started moult on time and overlapped it with breeding, associated with markedly slowed plumage change. Sex differences in moult score increased with lay date, but due to their respective modifications, both sexes delayed moult completion. Nonetheless, we could not detect any evidence for survival costs of late breeding. Breeding and moult of European Stonechats appear relatively flexible, despite migratory schedules and photoperiodic programs for seasonal timing. Individuals can modify seasonal behaviour in late summer, presumably depending on their condition, and may profit considerably from extended breeding.
Children at Familial Risk of Dyslexia: Practical Implications from an At‐Risk Study
Authors: Muter Valerie , Snowling Margaret J.
Published: June 2008

A longitudinal study was conducted of 50 at‐risk poor readers who were seen at four assessment points between the ages of three years and nine months and 12–13 years. This provided a wealth of data about the incidence of reading problems, the course of developmental relationships among language and literacy skills and the factors that influence outcome (including risk and protective factors and co‐morbid difficulties). The practical implications of this study are considered for the management of poor readers; including identifying children at‐risk of dyslexia, assessing and teaching poor readers, addressing co‐occurring difficulties, capitalising on compensatory or protective factors and providing emotional support.
Tier 4 Child and Adolescent Mental Health Services (CAMHS) ‐ Inpatient Care, Day Services and Alternatives: An Overview of Tier 4 CAMHS Provision in the UK
Authors: McDougall Tim , Worrall‐Davies Anne , Hewson Lesley , Richardson Greg , Cotgrove Andrew
Published: June 2008

This paper addresses Tier 4 services for children and young people whose needs require highly specialised services, and describes the range of provision which is currently available for this group. Although the evidence base is in its infancy, what is known about clinical outcomes, cost effectiveness and the views of users is summarised. The current shortfalls in tier 4 provision are highlighted, the drivers for change are identified and recommendations are made for future service improvements.
Quantifying Plant Population Persistence in Human‐Dominated Landscapes
Authors: LAWSON DAWN M. , LAMAR CERINA K. , SCHWARTZ MARK W.
Published: June 2008

Abstract:  We assessed population performance of rare plants across a gradient from rural to urban landscapes and evaluated 2 hypotheses central to strategic conservation planning: (1) population performance declines with increasing human dominance and (2) small populations perform poorly relative to larger ones. Assessing these hypotheses is critical to strategic conservation planning. The current conservation paradigm adheres to the well‐established ecology theory that small isolated populations, particularly those in human‐dominated landscapes, are the least likely to succeed over the long term. Consequently, conservation planning has strongly favored large, remote targets for protection. This shift in conservation toward ecosystem‐based programs and protection of populations within large, remote systems has been at the expense of protection of the rarest of the rare species, the dominant paradigm for conservation driven by the endangered species act. Yet, avoiding conservation of small populations appears to be based more on theoretical understanding and expert opinion than empiricism. We used Natural Heritage data from California in an assessment of population performance of rare plants across a landscape with an urban‐rural gradient. Population performance did not decrease in urban settings or for populations that were initially small. Our results are consistent with a pattern of few species extinctions within these landscapes over the past several decades. We conclude that these populations within compromised landscapes can contribute to overall biodiversity conservation. We further argue that conservation planning for biodiversity preservation should allocate relatively more resources to protecting urban‐associated plant taxa because they may provide conservation benefit beyond simply protecting isolated populations; they may be useful in building social interest in conservation.
Loss of Large Predatory Sharks from the Mediterranean Sea
Authors: FERRETTI FRANCESCO , MYERS RANSOM A. , SERENA FABRIZIO , LOTZE HEIKE K.
Published: June 2008

Abstract:  Evidence for severe declines in large predatory fishes is increasing around the world. Because of its long history of intense fishing, the Mediterranean Sea offers a unique perspective on fish population declines over historical timescales. We used a diverse set of records dating back to the early 19th and mid 20th century to reconstruct long‐term population trends of large predatory sharks in the northwestern Mediterranean Sea. We compiled 9 time series of abundance indices from commercial and recreational fishery landings, scientific surveys, and sighting records. Generalized linear models were used to extract instantaneous rates of change from each data set, and a meta‐analysis was conducted to compare population trends. Only 5 of the 20 species we considered had sufficient records for analysis. Hammerhead (Sphyrna spp.), blue (Prionace glauca), mackerel (Isurus oxyrinchus and Lamna nasus), and thresher sharks (Alopias vulpinus) declined between 96 and 99.99% relative to their former abundance. According to World Conservation Union (IUCN) criteria, these species would be considered critically endangered. So far, the lack of quantitative population assessments has impeded shark conservation in the Mediterranean Sea. Our study fills this critical information gap, suggesting that current levels of exploitation put large sharks at risk of extinction in the Mediterranean Sea. Possible ecosystem effects of these losses involve a disruption of top‐down control and a release of midlevel consumers.
Effects of Future Infrastructure Development on Threat Status and Occurrence of Amazonian Birds
Authors: VALE MARIANA M. , COHN‐HAFT MARIO , BERGEN SCOTT , PIMM STUART L.
Published: June 2008

Abstract:  Researchers predict that new infrastructure development will sharply increase the rate and extent of deforestation in the Brazilian Amazon. There are no predictions, however, of which species it will affect. We used a spatially explicit model that predicts the location of deforestation in the Brazilian Amazon by 2020 on the basis of historical patterns of deforestation following infrastructure development. We overlaid the predicted deforested areas onto maps of bird ranges to estimate the amount of habitat loss within species ranges. We also estimated the amount of habitat loss within modified ecoregions, which were used as surrogates for areas of bird endemism. We then used the extent of occurrence criterion of the World Conservation Union to predict the future conservation status of birds in the Brazilian Amazon. At current rates of development, our results show that at least 16 species will qualify as threatened or will lose more than half of their forested habitat. We also identified several subspecies and isolated populations that would also qualify as threatened. Most of the taxa we identified are not currently listed as threatened, and the majority are associated with riverine habitats, which have been largely ignored in bird conservation in Amazonia. These habitats and the species they hold will be increasingly relevant to conservation as river courses are altered and hydroelectric dams are constructed in the Brazilian Amazon.
The Paradox of Forest Fragmentation Genetics
Authors: KRAMER ANDREA T. , ISON JENNIFER L. , ASHLEY MARY V. , HOWE HENRY F.
Published: June 2008

Abstract:  Theory predicts widespread loss of genetic diversity from drift and inbreeding in trees subjected to habitat fragmentation, yet empirical support of this theory is scarce. We argue that population genetics theory may be misapplied in light of ecological realities that, when recognized, require scrutiny of underlying evolutionary assumptions. One ecological reality is that fragment boundaries often do not represent boundaries for mating populations of trees that benefit from long‐distance pollination, sometimes abetted by long‐distance seed dispersal. Where fragments do not delineate populations, genetic theory of small populations does not apply. Even in spatially isolated populations, where genetic theory may eventually apply, evolutionary arguments assume that samples from fragmented populations represent trees that have had sufficient time to experience drift, inbreeding, and ultimately inbreeding depression, an unwarranted assumption where stands in fragments are living relicts of largely unrelated predisturbance populations. Genetic degradation may not be as important as ecological degradation for many decades following habitat fragmentation.
Grasslands, People, and Conservation: Over‐the‐Horizon Learning Exchanges between African and American Pastoralists
Authors: CURTIN CHARLES , WESTERN DAVID
Published: June 2008

Abstract:  The world's grasslands and large migratory populations of wildlife have been disproportionately lost or disrupted by human activities, yet are poorly represented in protected areas. The major threats they face are land subdivision and the loss of large‐scale dynamic processes such as wildlife migrations and fire. The large‐scale dynamical processes and ubiquity of livestock economies and cultures across the grasslands calls for an integrated ecosystem approach to conservation to make up the shortfall in protected‐area coverage. Ranchers and pastoralists will be more inclined to adopt an integrated landscape approach to conservation if they also see the threats to wildlife and grassland ecosystems as affecting their livelihoods and way of life. We arranged a series of learning exchanges between African and American pastoralists, ranchers, scientists, and conservationists aimed at building the collaboration and consensus needed to conserve grasslands at a landscape level. There was broad agreement on the threat of land fragmentation to livelihoods, wildlife, and grasslands. The exchanges also identified weaknesses in prevailing public, private, and community modes of ownership in halting fragmentation. New collaborative approaches were explored to attain the benefits of privatization while keeping the landscape open. The African–U.S. exchanges showed that learning exchanges can anticipate over‐the‐horizon problems and speed up the feedback loops that underlie adaptive management and build social and ecological resilience.
Idiopathic Hypertrophic Cranial Pachymeningitis Presenting With Headache
Authors: Im So‐Hyang , Cho Keun‐Tae , Seo Hyung Suk , Choi Jong‐Sun
Published: June 2008

Idiopathic hypertrophic cranial pachymeningitis is a rare inflammatory disease, usually involving the dura mater of skull base, tentorium, and falx. Chronic headache is the most common clinical manifestations. We report a case of idiopathic hypertrophic cranial pachymeningitis that was, initially, misdiagnosed as acute subdural hematoma along the tentorium cerebelli and posterior falx on the brain precontrast CT scan of a patient with severe headache. Correct diagnosis of pachymeningitis was made only after brain magnetic resonance imaging and meningeal biopsy.
Single‐Point Assessment of Warfarin Use and Risk of Osteoporosis in Elderly Men
Authors: Woo Claudine , Chang Linda L. , Ewing Susan K. , Bauer Douglas C. ,   for the Osteoporotic Fractures in Men Study Group
Published: June 2008

OBJECTIVES: To determine whether warfarin use, assessed at a single point in time, is associated with bone mineral density (BMD), rates of bone loss, and fracture risk in older men.

DESIGN: Secondary analysis of data from a prospective cohort study.

SETTING: Six U.S. clinical centers.

PARTICIPANTS: Five thousand five hundred thirty‐three community‐dwelling, ambulatory men aged 65 and older with baseline warfarin use data.

MEASUREMENTS: Warfarin use was assessed as current use of warfarin at baseline using an electronic medication coding dictionary. BMD was measured at the hip and spine at baseline, and hip BMD was repeated at a follow‐up visit 3.4 years later. Self‐reported nonspine fractures were centrally adjudicated.

RESULTS: At baseline, the average age of the participants was 73.6 ± 5.9, and 321 (5.8%) were taking warfarin. Warfarin users had similar baseline BMD as nonusers (n=5,212) at the hip and spine (total hip 0.966 ± 0.008 vs 0.959 ± 0.002 g/cm2, P=.37; total spine 1.079 ± 0.010 vs 1.074 ± 0.003 g/cm2, P=.64). Of subjects with BMD at both visits, warfarin users (n=150) also had similar annualized bone loss at the total hip as nonusers (n=2,683) (−0.509 ± 0.082 vs −0.421 ± 0.019%/year, P=.29). During a mean follow‐up of 5.1 years, the risk of nonspine fracture was similar in warfarin users and nonusers (adjusted hazard ratio=1.06, 95% confidence interval=0.68–1.65).

CONCLUSION: In this cohort of elderly men, current warfarin use was not associated with lower BMD, accelerated bone loss, or higher nonspine fracture risk.
Changes in Prealbumin, Nutrient Intake, and Systemic Inflammation in Elderly Recuperative Care Patients
Authors: Dennis Richard A. , Johnson Larry E. , Roberson Paula K. , Heif Muhannad , Bopp Melinda M. , Cook Judy , Sullivan Dennis H.
Published: June 2008

OBJECTIVES: To determine the relationship between prealbumin, nutrient intake, and indicators of inflammation for recuperative and rehabilitative care patients.

DESIGN: Prospective cohort.

SETTING: Recuperative Care Unit within a Veterans Administration Nursing Home Care Unit.

PARTICIPANTS: One hundred eleven men (100 white; mean age 80, range 64–93).

MEASUREMENTS: Prealbumin and seven markers of inflammation (C‐reactive protein (CRP), tumor necrosis factor, and interleukin‐6 (IL‐6) and their soluble receptors) were measured at admission and discharge (median length of stay 23 days, interquartile range 15–40 days). Detailed calorie counts were performed daily, and intake was expressed as a percentage of estimated requirements for protein (1.5 g/kg body weight per day) and energy (Harris‐Benedict equation). The study objective was examined using least‐squares regression analysis.

RESULTS: Discharge prealbumin and the change in prealbumin were positively correlated with protein and energy intake and inversely correlated with markers of inflammation, particularly CRP and IL‐6. When all covariates were included in a multivariable regression analysis, the markers of inflammation predominantly accounted for the variance in prealbumin change (56%), whereas discharge protein intake accounted for 6%.

CONCLUSION: For older recuperative care patients, prealbumin and its change during hospitalization are positively associated with protein intake, but inflammation or changes in inflammation appear to exert a much more‐powerful influence on prealbumin concentration. Given the potential confounding effects of inflammation, monitoring the change in prealbumin is not an adequate substitute for a more‐detailed nutritional assessment in this population.
Effect of Polishing Technique and Brushing on Surface Roughness of Acrylic Resins
Authors: Oliveira Luciana Valadares , Mesquita Marcelo Ferraz , Henriques Guilherme Elias Pessanha , Consani Rafael Leonardo Xediek , Fragoso Wagner Sotero
Published: June 2008

Purpose: This study evaluated the abrasion resistance of acrylic resin to routine dental brushing procedures using different dentifrices after the resin surface had been chemically or mechanically polished.

Materials and Methods: Eighty specimens were prepared using heat‐polymerizing (HP) and autopolymerizing (AP) acrylic resin, and immediately submitted to grinding with abrasive stones and disks. The specimens were divided into two groups: the first group was mechanically polished (MP) using pumice slurry, and the second group was chemically polished (CP) using heated monomer. After polishing, the specimens were submitted to 30,000 brushing cycles. Surface roughness was measured after polishing and brushing procedures, using a Surfcorder SE 1700 rugosimeter. Data were statistically analyzed by ANOVA (α= 0.05).

Results: There were significant differences in surface roughness between polishing with MP and CP (p < 0.05). Significant differences in surface roughness were also found between brushing with MFP dentifrice and Tartar Control dentifrice (p < 0.05).

Conclusion: MP produced smoother surfaces than CP, and surface roughness as a result of polishing technique was not influenced by acrylic resin type. Even though MP resulted in smoother surfaces initially, subjecting the acrylic resin to dentifrice brushing negated this advantage.
Flexural Strength, Elastic Modulus, and pH Profile of Self‐etch Resin Luting Cements
Authors: Saskalauskaite Egle , Tam Laura E. , McComb Dorothy
Published: June 2008

Purpose: To determine the flexural strength, modulus of elasticity, and 24‐hour pH profile of three self‐etching resin luting cements and to obtain comparative data for representative conventional resin and resin‐modified glass ionomer luting cements.

Materials and Methods: Three self‐etching resin luting cements [RelyX Unicem (3M ESPE), Maxcem (Kerr), Embrace Wetbond (Pulpdent)] were tested and compared with two conventional resin cements [RelyX ARC (3M ESPE), Linkmax (GC)] plus two resin‐modified glass ionomer luting cements [Fuji Plus (GC), RelyX Luting Plus (3M ESPE)]. Flexural strength and modulus of elasticity were determined using bar‐shaped specimens (2 × 2 × 25 mm3) at 24 hours, using an Instron universal testing machine. Setting pH was measured using a flat‐surface pH electrode at 0, 2, 5, 15, and 30 minutes and 1, 2, 4, 6, and 24 hours after mixing. Testing was performed under both dual‐cured and self‐cured conditions for all dual‐cure cements. Data analysis included ANOVA and Tukey's test (p < 0.05).

Results: The self‐etching cements showed similar flexural strength to the conventional resin cements, except for Embrace Wetbond self‐cured, which was considerably lower. Modulus of elasticity results were both higher and lower than for conventional resin cements. All photopolymerized conventional and self‐etch dual‐cure cements showed markedly higher flexural strength and modulus than when solely self‐cured. The resin‐modified glass ionomer cements were characterized by lower flexural strength and elastic modulus. Self‐etching resin cements showed lower initial pH (2.0 to 2.4) than conventional resin cements (4.8 to 5.2) and a wide range of final pH values (3.9 to 7.3) at 24 hours. One self‐etching cement (Unicem) revealed a unique pH profile characterized by a more rapid rise in pH to neutrality both when dual‐cured (15 minutes) and when auto‐cured (1 hour).

Conclusions: The self‐etching resin cements evaluated in this study displayed disparate properties and cannot be considered a homogeneous group. Flexural strength properties were most uniform and were similar to those of the conventional resin cements, whereas moduli of elasticity showed greater variation. Setting pH profiles differed, depending on the brand and mode of cure, even within the same category of luting cement. All cements with dual‐cure capability, both conventional and self‐etch, showed significantly superior properties when photopolymerized.
Bivariate Evaluation of Cylinder Implant Diameter and Length: A Three‐Dimensional Finite Element Analysis
Authors: Kong Liang , Sun Yingying , Hu Kaijin , Li Dehua , Hou Rui , Yang Jin , Liu Baolin
Published: June 2008

Purpose: To evaluate continuous and simultaneous variations of implant diameter and length for an experimental cylinder implant.

Materials and Methods: A finite element model of a mandible segment with implant was created. The range of implant diameter (D) was set from 2.5 to 5.0 mm, and that of implant length (L) from 6.0 to 16.0 mm. The maximum Von Mises stresses in the mandible were evaluated, and the sensitivity of the stresses in the mandible to the variables was also evaluated.

Results: Under axial load, the maximum von Mises stresses in cortical and cancellous bones decreased by 73.3% and 69.4%, respectively, with D and L increasing. Under buccolingual load, those decreased 83.8% and 79.2%, respectively. When D exceeded 3.9 mm and L exceeded 10.0 mm, the tangent slope rate of the maximum von Mises stress response curve ranged from −1 to 0. The variation of the maximum von Mises stresses in the mandible was more sensitive to D than to L.

Conclusions: Buccolingual force is apt to be influenced by the two implant parameters; implant diameter and length favor stress distribution in cortical bone and cancellous bone, respectively. Implant diameter exceeding 3.9 mm and implant length exceeding 10.0 mm are the optimal choice for type B/2 bone in a cylinder implant. The implant diameter is more important than length in reducing bone stress.
Effect of Framework Shape on the Fracture Strength of Implant‐Supported All‐Ceramic Fixed Partial Dentures in the Molar Region
Authors: Tsumita Mitsuyoshi , Kokubo Yuji , Von Steyern Per Vult , Fukushima Shunji
Published: June 2008

Purpose: The aim of the present study was to clarify the effects of the shape of the zirconium framework of implant‐supported, all‐ceramic fixed partial dentures (FPDs) on the fracture strength and fracture mode.

Materials and Methods: This study consisted of mechanical strength testing and 3D finite element analysis (FEA). The three framework shapes used in this study were: (1) conventional shape (control); (2) convex shape: 1.0‐mm curve in the direction of the occlusal surface; and (3) concave shape: 1.0‐mm curve in the direction of the gingival surface. Five frameworks were made for each condition (total: 15). A load (N) was applied until the FPD fractured. For FEA, a 3D model consisting of cortical bone, cancellous bone, implant bodies, and superstructure was constructed.

Results: The results of the mechanical strength test showed that fracture load was 916.0 ± 150.1 N for the conventional shape, 1690.5 ± 205.3 N for the convex shape, and 1515.5 ± 137.0 N for the concave shape. The mean final fracture load for the FPDs with frameworks was the highest for the convex shape; however, a critical crack in the veneer porcelain (736.5 ± 145.2 N) was confirmed during loading for the convex shape. Stress distribution maps for all conditions showed that tensile stress was generated at the veneer porcelain on the gingival side of the mesial and distal connectors of the pontic; however, there were differences in the maximum value and stress distribution within the framework.

Conclusion: The shape of the framework, particularly the shape of the pontic–connector interface, affects the stress distribution, fracture strength, and fracture mode of all‐ceramic FPDs, and stress concentration inside a framework may induce cracking of layering porcelain.
Computerized Color Formulation for African‐Canadian People Requiring Facial Prostheses: A Pilot Study
Authors: Coward T.J. , Seelaus R. , Li S.Y.
Published: June 2008

Purpose: The aim of this study was to investigate the effectiveness of spectrophotometry and a computerized color formulation system to predict pigment formulas for color mixing silicone elastomer to match the skin color of African‐Canadian people.

Materials and Methods: In a prospective study, reflectance spectrophotometery was used to measure the skin color of 19 African‐Canadian subjects. The spectral data for each subject was used in a computerized color formulation system to predict colorants required to mix silicone elastomer to match each subject's skin color. Delta‐E values were recorded for each silicone sample in comparison to the subject's skin measurement. An analysis of variance was used to determine significance among variables, and a Tukey HSD post hoc test was used to assess paired comparisons.

Results: Delta‐E decreased with iterative mixes of colored silicone for each subject, and pigment loading increased with iterative mixes. Delta‐E values for the third iterative mix (fourth and final sample) ranged between 1.49 and 8.82.

Conclusion: Spectrophotometry and computerized color formulation provide a foundation in the color matching procedure for facial prostheses that offers objectivity to an otherwise subjective task. Through further study of spectrophotometry and computerized color formulation, and with the development of pigment databases appropriate for the African‐Canadian population, it may be possible to establish a precise and repeatable color matching system that predicts required colorants and controls metamerism.
Effect of Arm Design and Chemical Polishing on Retentive Force of Cast Titanium Alloy Clasps
Authors: Shimpo Hidemasa
Published: June 2008

Purpose: Titanium dentures have recently increased in popularity. A decrease in the retentive force of the titanium clasps has frequently been observed. This study investigated the effect of retentive arm design and chemical polishing of titanium clasps.

Materials and Methods: Four Akers clasps with 0.25‐mm and 0.5‐mm undercuts were designed so that the retentive arms were placed at 1/2 and 2/3 of the undercut area. Wax patterns were fabricated and invested in phosphate‐bonded Al2O3/LiAl SiO6. They were cast with CP Ti Grade 2, CP Ti Grade 3, and Ti‐6Al‐7Nb using an argon gas‐pressure casting unit (Autocast HC‐III). After sandblasting, the castings were chemically treated with an HNO3/HF solution. The retentive force (N) was measured up to 10,000 insertion/removal times. The results (n = 5) were analyzed by ANOVA/Tukey's test (α= 0.05).

Results: The retentive forces significantly decreased with increasing immersion time in the HNO3/HF solution (p < 0.05). The retentive force of the 2/3 undercut was significantly greater than that of the 1/2 undercut (p < 0.05). Excluding the initial insertion/removal period of the 2/3 undercut, there were no significant differences among all the titanium metals tested (p > 0.05). As the number of insertion/removal times increased, the retentive force of the 2/3 undercut greatly decreased. The retentive force of the Ti‐6Al‐7Nb clasps for the 1/2 undercut decreased the least after 10,000 insertion/removal times.

Conclusions: Chemical treatment for titanium clasps should be performed for 1– 5 minutes due to the following factors: accuracy, surface roughness, surface structure, initial retention, and stability of retention. To maintain appropriate long‐term retentive force, the retentive arms should be placed in the 1/2 undercut area of the abutment tooth.
Implant Surface Modification Using Laser Guided Coatings: In Vitro Comparison of Mechanical Properties
Authors: Vasanthan Asvin , Kim Hyunbin , Drukteinis Saulius , Lacefield William
Published: June 2008

Purpose: Plasma‐sprayed hydroxyapatite (HA)‐coated implants show failures along the coating–substrate interface due to poor bond strength. We analyzed HA coatings obtained by pulsed laser deposition (PLD) and compared them to commercially used plasma‐sprayed coatings with respect to their bond strength to titanium alloy (Ti‐6Al‐4V), as well as surface roughness alterations produced by each of the two deposition methods.

Materials and Methods: Twelve titanium alloy disks were plasma‐sprayed under commercial implant coating conditions, and 24 titanium alloy disks were coated using PLD. All coatings were characterized by the presence of the different calcium phosphate (CaP) phases. The plasma‐sprayed coatings (n = 12) were predominantly HA, and the pulsed laser‐deposited coatings were hydroxydyapatite (n = 12) and HA coating with a tetra calcium phosphate (TTCP) phase (n = 12). The surface roughness was analyzed before and after the coating processes to assess roughness changes to the surface by the coatings. The adhesive bond strengths of these coatings to the substrate titanium alloy was tested and compared. Scheffé's test was used to analyze the statistical significance of the data.

Results: The surface roughness alteration following PLD was a decrease of 0.2 μm, whereas following plasma spraying the decrease was 1.0 μm. Bond strengths were as follows [mean (SD) in MPa]: pulsed laser‐deposited HA coatings: 68.3 (17.8); pulsed laser‐deposited HA with tetra‐CaP: 55.2 (21.1); plasma‐sprayed HA 17.0 (2.8). The multivariate Scheffé's test revealed that HA coatings obtained by PLD had significantly increased bond strengths compared with the plasma sprayed ones (p≤ 0.05).

Conclusions: HA coatings obtained by PLD showed greater adherence to titanium alloy. PLD offers an alternative method to produce thinner coatings with better adherence properties, along with precise control over the deposition process.
Resin‐Bonded Overcasting to Salvage a Long‐Span Fixed Prosthesis: A Clinical Report
Authors: Shimizu Hiroshi , Takahashi Yutaka
Published: June 2008

To salvage a failing long‐span fixed partial denture (FPD), a resin‐bonded overcasting made of a silver‐palladium‐copper‐gold alloy was fabricated and cemented using an adhesive metal conditioner and adhesive resin luting agent to an existing multiple‐abutment FPD.
Using the Pinledge as a Conservative Retainer: A Clinical Report
Authors: Over Larry Michael
Published: June 2008

Prior to the invention of the metal ceramic crown, the pinledge retainer served prosthodontic dentistry for many years. The metal ceramic retainer has been the standard of choice for the majority of fixed partial dentures (FPDs) for nearly 40 years. Recent advances with acid‐etched, resin‐bonded metal retainers and most recently all‐ceramic retainers may have led many to believe that the pinledge retainer is an outdated treatment modality. This clinical report provides examples of several types of pinledge retainers used to restore missing teeth or to splint teeth. These patient examples will also demonstrate that the pinledge retainer can provide excellent esthetics for today's appearance‐conscious patients.
ICK Classification System for Partially Edentulous Arches
Authors: Al‐Johany Sulieman S. , Andres Carl
Published: June 2008

Several methods of classification of partially edentulous arches have been proposed and are in use. The most familiar classifications are those originally proposed by Kennedy, Cummer, and Bailyn. None of these classification systems include implants, simply because most of them were proposed before implants became widely accepted. At this time, there is no classification system for partially edentulous arches incorporating implants placed or to be placed in the edentulous spaces for a removable partial denture (RPD). This article proposes a simple classification system for partially edentulous arches with implants based on the Kennedy classification system, with modification, to be used for RPDs. It incorporates the number and positions of implants placed or to be placed in the edentulous areas. A different name, Implant‐Corrected Kennedy (ICK) Classification System, is given to the new classification system to be differentiated from other partially edentulous arch classification systems.
Compressive Damage to the Deep Branch of the Lateral Plantar Nerve Associated with Lameness Caused by Proximal Suspensory Desmitis
Authors: TÓTH FERENC , SCHUMACHER JIM , SCHRAMME MICHAEL , HOLDER TROY , ADAIR H. STEVE , DONNELL ROBERT L.
Published: June 2008

Objective— To describe pathologic changes in the deep branch of the lateral plantar nerve (DBLPN) of horses determined to be lame because of proximal suspensory desmitis (PSD), and to report the outcome after treatment by excision of a segment of the horses' DBLPN.

Study Design— Retrospective case series.

Animals— Adult horses (n=16).

Methods— Horses determined to be lame on one or both pelvic limbs because of PSD were treated by excision of a segment of the DBLPN, and 30 nerves were examined histologically. Owners were contacted to obtain information about the horses ≥6 months after surgery.

Results— Histologic changes suggestive of chronic nerve compression were identified in both nerves of 11 bilaterally lame horses and in the lame limb of 5 unilaterally lame horses. The nerve of the sound limb of 2 of 3 unilaterally lame horses that had bilateral nerve resection also had histologic changes compatible with nerve compression. Ten of 16 horses (62.5%) with follow‐up information returned to soundness after excision of the DBLPN.

Conclusions— Pathologic changes of the DBLPN associated with compression may complicate PSD of the pelvic limbs. Excision of the nerve may resolve lameness caused by PSD.

Clinical Relevance— Horses lame because of PSD of the pelvic limb may remain lame after desmitis has resolved because of compression of the DBLPN. Excising a portion of this nerve may resolve lameness.
The Influence of a Novel Organ Perfusion Solution on Early Graft Function in Canine Renal Autotransplantation
Authors: POLYAK MAXIMILIAN M.R. , GROSCHE ASTRID , TOWL SIMON , MORTON ALISON J.
Published: June 2008

Objective— To evaluate the influence of a kidney perfusion solution on early graft function in dogs.

Study Design— Experimental, randomized study.

Animals— Intact adult male mongrel dogs (n=12).

Methods— Dogs had renal autograft transplantation without ureteroneocystotomy with contralateral nephrectomy. Kidney graft flushing with a novel organ perfusion solution was compared with flushing with saline (0.9% NaCl) solution. Serum creatinine (Cr) and blood urea nitrogen (BUN) concentrations were measured daily posttransplant for 7 days. Ultrasound‐guided renal biopsy was performed on postoperative day 1 for electron microscopic evaluation. Dogs were euthanatized on day 7.

Results— All dogs completed the study. Cr and BUN concentrations of the saline group were significantly greater than the organ perfusion solution group on each postoperative day (P=.01 for S Cr; P=.001 for BUN). Electron micrographs of nuclei and mitochondria from convoluted proximal tubule cells indicated profound ultrastructural disruptions in the saline group and mild ultrastructural disruptions in the organ perfusion solution group.

Conclusion— Flushing solution composition can influence early graft function in live donor kidney transplantation.

Clinical Relevance— Use of a specialized flushing solution can improve early graft function in canine kidney transplantation, independent of antigen‐mediated events.
Computed Tomography Versus Arthroscopy for Detection of Canine Elbow Dysplasia Lesions
Authors: MOORES ANDREW P. , BENIGNI LIVIA , LAMB CHRISTOPHER R.
Published: June 2008

Objective—To describe associations between computed tomography (CT) and arthroscopy in dogs with elbow dysplasia lesions.

Study Design—Retrospective clinical study.

Sample Population—Canine elbows (n=101) investigated by CT and arthroscopy.

Methods—CT scans were reviewed for 10 predetermined CT signs and graded for osteophyte size. Surgical reports were reviewed for specific disease features and cartilage erosion grades. Associations between variables were investigated with multivariate logistic regression and correlation between osteophyte size and cartilage erosion with Spearman's rank order correlation.

Results—Medial coronoid process (MCP) fragment on CT was significantly associated with the arthroscopic identification of a displaced MCP fragment, cartilage erosion affecting the MCP, and cartilage erosion affecting the humeral condyle. Irregular radial incisure of the ulna on CT was significantly associated with the arthroscopic identification of cartilage erosion affecting the MCP. Osteophytes on CT were significantly associated with an abnormal arthroscopic examination. There was a moderately significant correlation between CT osteophyte grade and cartilage erosion grades for areas of the medial joint compartment (rs=0.44–0.48).

Conclusion—Some CT signs are significantly associated with arthroscopic features of elbow dysplasia lesions in dogs; however, other CT signs were not associated with arthroscopic findings, and CT and arthroscopy can provide contradictory information. Osteophyte size is moderately correlated with cartilage erosion of the medial joint compartment.

Clinical Relevance—CT can provide valuable information for the investigation of dogs with elbow dysplasia, but the absence of CT signs (or the absence of arthroscopic abnormalities) does not rule out elbow lesions.
Evaluation of Wraps Covering the Distal Aspect of Pelvic Limbs for Prevention of Bacterial Strike‐Through in an Ex Vivo Canine Model
Authors: VINCE KENT J. , LASCELLES B. DUNCAN X. , MATHEWS KYLE G. , ALTIER CRAIG , ROE SIMON C.
Published: June 2008

Objective—To determine differences in bacterial strike‐through for materials commonly used to cover the distal aspect of the pelvic limb during operative site preparation.

Study Design—Randomized block design; ex vivo model.

Animals—Canine cadaveric pelvic limbs (n=40).

Methods—Pelvic limbs (n=40) were randomly assigned to 4 treatment groups: Group 1=Vetrap™+sterile Coban™; Group 2=latex glove+Vetrap™+sterile Coban™; Group 3=latex glove+Vetrap™+sterile Coban™+sterile latex glove+sterile Coban™; and Group 4=latex glove+Vetrap™+sterile disposable drape+sterile Coban™. Limbs were contaminated with a standardized bacterial solution and routinely prepared using the assigned distal leg wrap. Bandages were fluid challenged with a saline (0.9% NaCl) solution‐soaked laparotomy sponge for 30 seconds. The wrap surface was sampled for microbial culture before surgical preparation, immediately after, and 60 minutes after applying a sterile leg wrap.

Results—Bacterial growth occurred in all Group 1 cultures, 90% of Group 2 cultures, and none of the Group 3 and 4 cultures, 60 minutes after applying the sterile wrap.

Conclusion—A distal leg wrap of Vetrap™+sterile Coban™is not effective in preventing bacterial strike‐through.

Clinical Relevance—If similar results occur in the live animal, then a sterile impermeable barrier must be incorporated into the distal leg wrap to prevent bacterial strike‐through.
Recommendations for an Effective 2008 Transition
Authors: Johnson Clay
Published: June 2008

In response to Martha Joynt Kumar’s essay on maximizing presidential transitions while minimizing hazards, this essay presents additional practical recommendations, framed within the context of the upcoming presidential transition.