bluuebunny/crossref_metadata_2025 huggingface dataset:
Myocutaneous flap reconstruction of the perineum after radical abdominoperineal resection
Authors: Ramesh A. N. , Gajanan K. , Fulford P. E. , Wilson M. S. , O’Dwyer S. T.
Published: January 2007

Objective:  Wound dehiscence with nonhealing of the perineum is a significant morbidity associated with radical abdominoperineal resection (APR). Myocutaneous flaps have been used to facilitate primary wound healing. The purpose of this study is to evaluate the results of myocutaneous flap reconstruction of the perineum following radical APR.

Method:  The clinical records of patients who had myocutaneous flap reconstruction of the perineum between 2000 and 2005 were reviewed. Details of wound healing and complications related to the flaps were recorded.

Results:  Seventeen patients with a median age of 59 (range 29–77) years had primary reconstruction of the perineum with gracilis (10), rectus abdominis (6) and gluteal (1) myocutaneous flaps. Malignancy of the anus (12) and rectum (4) was the primary pathology and one patient had chronic perianal Crohn's fistulae. An 11 patients had preoperative radiotherapy in this group. Complete healing of the perineum was achieved in 16 (94.2%) of the 17 patients. There were 8 (47%) minor wound dehiscence and 2 (11%) skin necrosis all of which healed completely and 1 (5.8%) total flap necrosis.

Discussion:  Myocutaneous flaps improve wound healing with only minor morbidity in majority of patients and should be considered routinely to close perineal defects following radical APR particularly in irradiated perineum.
Working with concepts in the fuzzy front end: exploring the context for innovation for different types of concepts at Volvo Cars
Authors: Backman Maria , Börjesson Sofia , Setterberg Sten
Published: January 2007

Automotive firms are balancing the increasing needs for cost and time efficiency with the necessity of developing more innovative products to stand out on in a competitive market. The strive for efficiency has led to an increasingly structured development process with limited allowances for deviations. Previous academic work has pointed out the importance and embedded potential of the fuzzy front end, where new concepts still have the possibility to impact the new product development (NPD) process. However, most research has focused on the transfer of new technologies, while concepts based on e.g. customer or market knowledge have been more or less neglected. This paper discusses the need for alternative and contingent approaches in the front end of NPD to also consider the transfer of other types of concepts. More specifically, it addresses the need to distinguish between different types of concepts and to explore their different prerequisites in NPD. It is argued that customer‐ and market‐based concepts experience certain difficulties due to the history and power of technology in research and development (R&D) domains in the automotive context as well as a lack of support from the existing, formal processes. In this paper, we argue that all new concepts need to be conceptualized before being introduced to the NPD process, but that does not always suffice. Concepts other than technology concepts also need a contingent package to enable an evaluation in the context of the R&D process – they need to be contextualized. This paper draws on an in‐depth case study of Volvo Cars within a long‐lasting collaborative research setup. It is based on an interview study with key persons in the areas of concept work and NPD, and uses an insider/outsider approach.
An extension to a DEA support system used for assessing R&D projects
Authors: Linton Jonathan D. , Morabito Joseph , Yeomans Julian Scott
Published: January 2007

This paper describes an extension to the data envelopment analysis (DEA) support system that has been used for the assessment, rating, and ranking of diverse portfolios of research and development (R&D) projects at Lucent Technologies. The approach is illustrated through its application to a large portfolio of R&D projects considered by Lucent's Advanced Technologies Group. The method proceeds by first stratifying the portfolio into comparably efficient groups of projects through the construction of a series of efficient DEA frontiers, and then by lexicographically ranking each project within these groups relative to DEA‐based contextual attractiveness measures calculated from the different partitions. The advantages to this approach are provided not only from the perspective of the specific project rankings that are produced but also from the broader managerial insights that can be derived from any resulting differences between officially sanctioned, quantitative decision‐making procedures, and the quality of the decisions that have actually been made by managers.
Innovation and project development: an impossible equation? Lessons from an innovative automobile project development
Authors: Aggeri Franck , Segrestin Blanche
Published: January 2007

Product development performance has become a key issue for car manufacturers. But innovation seeks to outperform dominant design, whereas project development targets well‐defined areas (costs, lead times, quality, etc.). This article provides an analysis of the extent to which innovation is compatible with recent managerial and technical methods (project and multi‐project management, co‐development, simulation tools and digital mock‐ups, etc.). The analysis is based on a recent development project conducted at Renault in which these various techniques were used in an attempt to achieve highly ambitious targets simultaneously in the areas of lead times, costs and innovation. During the course of the project, unexpected design problems revealed failures in co‐ordination, monitoring procedures and expertise. We argue that recent project development methods can induce negative effects on collective learning processes and that these effects have managerial implications for innovative developments.
Cost management and cross‐functional communication through product architectures
Authors: Zwerink Ruud , Wouters Marc , Hissel Paul , Kerssens‐van Drongelen Inge
Published: January 2007

Product architecture decisions regarding, for example, product modularity, component commonality, and design re‐use, are important for balancing costs, responsiveness, quality, and other important business objectives. Firms are challenged with complex tradeoffs between competing design priorities, face the need to facilitate communication between functional silos, and want to learn from past experiences. In this paper, we present a qualitative approach for systematically evaluating the product architecture of a product family, comparing the original architecture objectives and actual experiences.

The intended contribution of our research is threefold: (1) to present a framework that brings together a diverse set of product architecture‐related decisions and business performance; (2) to provide a set of metrics that operationalise the variables in the framework, and (3) to provide a workshop protocol that is based on the framework and the metrics. This workshop aims to improve cross‐functional communication about the product architecture of an existing product family, and it results in practical improvement actions for future architecture design projects. Experiences with this approach are reported in pilots with Philips Domestic Appliances and Personal Care, and Philips Consumer Electronics.
(Not) Taking Account of Precarious Employment: Workfare Policies and Lone Mothers in Ontario and the UK
Authors: Evans Patricia M.
Published: January 2007

Workfare is, at least in part, a policy response to changing labour markets and the expansion taking place in jobs that are low‐paid, irregular and insecure. For lone mothers, increasingly the focus of workfare policies, precarious employment creates special challenges. However, the nature of the jobs that are available to women on social assistance has received relatively little attention in the workfare literature, which focuses more on individual characteristics, supports to employment, and programme impacts. Drawing upon both primary and secondary sources and using Ontario, the province with the most developed workfare programme in Canada, this article examines the ways in which policies support and enforce precarious employment. The article also considers the implications of precarious employment for UK policy, which has not (yet) adopted workfare for lone mothers, although incremental steps in that direction are taking place as employment is increasingly viewed as the appropriate objective of income support programmes for lone mothers.
Toward Optimal Calibration of the SLEUTH Land Use Change Model
Authors: Dietzel Charles , Clarke Keith C
Published: January 2007

SLEUTH is a computational simulation model that uses adaptive cellular automata to simulate the way cities grow and change their surrounding land uses. It has long been known that models are of most value when calibrated, and that using back‐casting (testing against known prior data) is an effective calibration method. SLEUTH's calibration uses the brute force method: every possible combination and permutation of its control parameters is tried, and the outcomes tested for their success at replicating prior data. Of the SLEUTH calibration approaches tried so far, there have been several suggested rules to follow during the brute force procedure to deal with problems of tractability, most of which leave out many of the possible parameter combinations. In this research, we instead attempt to create the complete set of possible outcomes with the goal of examining them to select the optimum from among the millions of possibilities. The self‐organizing map (SOM) was used as a data reduction method to pursue the isolation of the best parameter sets, and to indicate which of the existing 13 calibration metrics used in SLEUTH are necessary to arrive at the optimum. As a result, a new metric is proposed that will be of value in future SLEUTH applications. The new measure combines seven of the current measures, eight if land use is modeled, and is recommended as a way to make SLEUTH applications more directly comparable, and to give superior modeling and forecasting results.
The Performance of Vector Oriented Data Storage Strategies in ESRI's ArcGIS
Authors: Batcheller James K , Gittings Bruce M , Dowers Steve
Published: January 2007

The emergence of Geographical Information Systems (GIS) as an important tool in the analysis of spatial phenomena has been mirrored by the evolution of the data models underpinning such systems. When considering vector‐based solutions, such developments have seen a migration from single‐user, file‐based, topologicalhybridmodels to multi‐user database management system (DBMS) basedintegratedformats, often with no inherent topology. With all these solutions still being readily available, the decision of which to employ for a given application is a complicated one. This study analyses the performance of a number of vector data storage formats for use with ESRI's ArcGIS, with the aim to facilitate the ‘intelligent selection’ of an appropriate solution. Such a solution will depend upon the application domain and both single‐user and multi‐user (corporate) scenarios are considered. Findings indicate that single‐user ESRIcoveragesand multi‐user ArSDE/Oracle strategies perform better when considering the range of GIS operations used to evaluate data store performance.
Framework and Workflows for Spatial Database Generalization
Authors: Choe Byong‐Nam , Kim Young‐Gul
Published: January 2007

Spatial database generalization deals not only with geometrical simplification, but also with changes in database schema and content. The purpose of this research is to suggest methods for database generalization through the abstraction of a detailed spatial database. To accomplish this goal, this study suggests a framework for database generalization, and then defines operators that reflect the changes in database schema and content within the generalization process. A set of operator sequences (workflows) is used to specify and arrange the operators required to abstract a given feature. In order to assess the validity of the suggested method, a prototype system is developed. The results show that the efficiency of generalization can be improved, and data loss or distortion reduced as well.
Detection and Risk for Digging Activities around Underground Cables and Pipelines: Implications for Spatial Data Quality
Authors: Van Oort P A J , Bregt A K , De Bruin S
Published: January 2007

Digging activities are considered the largest cause of damage to underground cables and pipelines. Contractors can reduce the risk through detection, which will cost time and thus money. In the Netherlands, maps are the prime source of information on the location of cables/pipelines and detection time strongly depends on whether maps indicate the presence of cables and pipelines. Poor quality maps can contribute to increased risk or higher risk avoidance costs. The objective of this article is to present a model for calculating the trade‐off between detection costs and risk in case of a hit and for calculating implications of over‐ and incompleteness of maps. The model aims to find the optimal detection time at which the sum of detection cost and risk is at its minimum. A case‐study showed that it is possible to parameterise the model with data collected from contractors through a questionnaire. The case‐study provides a numerical example of calculation of the trade‐off between risk and detection costs and provides an example of calculation of costs of incompleteness. We conclude that the model contributes valuable new insight. However, more and location specific data are needed to enable operational use of the model.
Regression coefficient and autoregressive order shrinkage and selection via the lasso
Authors: Wang Hansheng , Li Guodong , Tsai Chih-Ling
Published: January 2007

The least absolute shrinkage and selection operator (‘lasso’) has been widely used in regression shrinkage and selection. We extend its application to the regression model with autoregressive errors. Two types of lasso estimators are carefully studied. The first is similar to the traditional lasso estimator with only two tuning parameters (one for regression coefficients and the other for autoregression coefficients). These tuning parameters can be easily calculated via a data-driven method, but the resulting lasso estimator may not be fully efficient. To overcome this limitation, we propose a second lasso estimator which uses different tuning parameters for each coefficient. We show that this modified lasso can produce the estimator as efficiently as the oracle. Moreover, we propose an algorithm for tuning parameter estimates to obtain the modified lasso estimator. Simulation studies demonstrate that the modified estimator is superior to the traditional estimator. One empirical example is also presented to illustrate the usefulness of lasso estimators. The extension of the lasso to the autoregression with exogenous variables model is briefly discussed.
Marginal Regression Analysis of Longitudinal Data With Time-Dependent Covariates: A Generalized Method-of-Moments Approach
Authors: Lai Tze Leung , Small Dylan
Published: January 2007

We develop a new approach to using estimating equations to estimate marginal regression models for longitudinal data with time-dependent covariates. Our approach classifies time-dependent covariates into three types—types I, II and III. The type of covariate determines what estimating equations can be used involving the covariate. We use the generalized method of moments to make optimal use of the estimating equations that are made available by the covariates. Previous literature has suggested the use of generalized estimating equations with the independent working correlation when there are time-dependent covariates. We conduct a simulation study that shows that our approach can provide substantial gains in efficiency over generalized estimating equations with the independent working correlation when a time-dependent covariate is of types I or II, and our approach remains consistent and comparable in efficiency with generalized estimating equations with the independent working correlation when a time-dependent covariate is of type III. We apply our approach to analyse the relationship between the body mass index and future morbidity among children in the Philippines.
An Examination of the Reliability of Prestigious Scholarly Journals: Evidence and Implications for Decision‐Makers
Authors: OSWALD ANDREW J.
Published: January 2007

Scientific‐funding bodies are increasingly under pressure to use journal rankings to measure research quality. Hiring and promotion committees routinely hear an equivalent argument: ‘this is important work because it is to be published in prestigious journal X’. But how persuasive is such an argument? This paper examines data on citations to articles published 25 years ago. It finds that it is better to write the best article published in an issue of a medium‐quality journal such as the OBES than all four of the worst four articles published in an issue of an elite journal like the AER. Decision‐makers need to understand this.
Widespread neuronal expression of branched‐chain aminotransferase in the CNS: implications for leucine/glutamate metabolism and for signaling by amino acids
Authors: García‐Espinosa María A. , Wallin Reidar , Hutson Susan M. , Sweatt Andrew J.
Published: January 2007

Transamination of the branched‐chain amino acids produces glutamate and branched‐chain α‐ketoacids. The reaction is catalyzed by branched‐chain aminotransferase (BCAT), of which there are cytosolic and mitochondrial isoforms (BCATc and BCATm). BCATc accounts for 70% of brain BCAT activity, and contributes at least 30% of the nitrogen required for glutamate synthesis. In previous work, we showed that BCATc is present in the processes of glutamatergic neurons and in cell bodies of GABAergic neurons in hippocampus and cerebellum. Here we show that this metabolic enzyme is expressed throughout the brain and spinal cord, with distinct differences in regional and intracellular patterns of expression. In the cerebral cortex, BCATc is present in GABAergic interneurons and in pyramidal cell axons and proximal dendrites. Axonal labeling for BCATc continues into the corpus callosum and internal capsule. BCATc is expressed by GABAergic neurons in the basal ganglia and by glutamatergic neurons in the hypothalamus, midbrain, brainstem, and dorsal root ganglia. BCATc is also expressed in hypothalamic peptidergic neurons, brainstem serotoninergic neurons, and spinal cord motor neurons. The results indicate that BCATc accumulates in neuronal cell bodies in some regions, while elsewhere it is exported to axons and nerve terminals. The enzyme is in a position to influence pools of glutamate in a variety of neuronal types. BCATc may also provide neurons with sensitivity to nutrient‐derived BCAAs, which may be important in regions that control feeding behavior, such as the arcuate nucleus of the hypothalamus, where neurons express high levels of BCATc.
Dopamine activates Nrf2‐regulated neuroprotective pathways in astrocytes and meningeal cells
Authors: Shih Andy Y. , Erb Heidi , Murphy Timothy H.
Published: January 2007

The transcription factor Nrf2 controls inducible expression of multiple antioxidant/detoxification genes. We previously found that Nrf2‐/‐ mice have increased sensitivity to in vivo mitochondrial stress and ischemia. Although Nrf2 regulated these forms of neuronal toxicity, it was unclear which injury‐triggered signal(s) led to Nrf2 activation in vivo. In this study, we use primary cultures to test the hypothesis that excessive dopamine release can act as an endogenous Nrf2‐inducing signal. We cultured two cell types that show increased Nrf2 activity during ischemia in vivo, astrocytes and meningeal cells. Cultures were infected with an adenovirus reporter of Nrf2 transcriptional activity. Dopamine‐induced Nrf2 activity in both cell types by generating oxidative stressors, H2O2 and dopamine‐quinones. Nrf2 activation in meningeal cells was significantly higher than astrocytes. The effect of dopamine was blocked by antioxidants, and by over‐expression of either dominant‐negative Nrf2 or Keap1. Nrf2 induction was specific to oxidative stress caused by catecholaminergic neurotransmitters as epinephrine also induced Nrf2, but the monoamine serotonin had no significant effect. These in vitro results suggest Nrf2 activity in astrocytes and meningeal cells link the neurotoxic actions of dopamine to neuroprotective pathways that may potentially modulate ischemic injury and neurodegeneration.
Energy sources for glutamate neurotransmission in the retina: absence of the aspartate/glutamate carrier produces reliance on glycolysis in glia
Authors: Xu Y. , Ola M. S. , Berkich D. A. , Gardner T. W. , Barber A. J. , Palmieri F. , Hutson S. M. , LaNoue K. F.
Published: January 2007

The mitochondrial transporter, the aspartate/glutamate carrier (AGC), is a necessary component of the malate/aspartate cycle, which promotes the transfer into mitochondria of reducing equivalents generated in the cytosol during glycolysis. Without transfer of cytosolic reducing equivalents into mitochondria, neither glucose nor lactate can be completely oxidized. In the present study, immunohistochemistry was used to demonstrate the absence of AGC from retinal glia (Müller cells), but its presence in neurons and photoreceptor cells. To determine the influence of the absence of AGC on sources of ATP for glutamate neurotransmission, neurotransmission was estimated in both light‐ and dark‐adapted retinas by measuring flux through the glutamate/glutamine cycle and the effect of light on ATP‐generating reactions. Neurotransmission was 80% faster in the dark as expected, because photoreceptors become depolarized in the dark and this depolarization induces release of excitatory glutamate neurotransmitter. Oxidation of [U‐14C]glucose, [1‐14C]lactate, and [1‐14C]pyruvate in light‐ and dark‐adapted excised retinas was estimated by collecting 14CO2. Neither glucose nor lactate oxidation that require participation of the malate/aspartate shuttle increased in the dark, but pyruvate oxidation that does not require the malate/aspartate shuttle increased to 36% in the dark. Aerobic glycolysis was estimated by measuring the rate of lactate appearance. Glycolysis was 37% faster in the dark. It appears that in the retina, ATP consumed during glutamatergic neurotransmission is replenished by ATP generated glycolytically within the retinal Müller cells and that oxidation of glucose within the Müller cells does not occur or occurs only slowly.
Autoantibodies to alpha‐synuclein in inherited Parkinson’s disease
Authors: Papachroni Katerina K. , Ninkina Natalia , Papapanagiotou Angeliki , Hadjigeorgiou Georgios M. , Xiromerisiou Georgia , Papadimitriou Alexandros , Kalofoutis Anastasios , Buchman Vladimir L.
Published: January 2007

Neurodegeneration in Parkinson’s disease (PD) is accompanied by a local immune reaction in the affected brain regions. It is well established that α‐synuclein is directly implicated in the pathogenesis of PD. Development of the disease is often associated with changes of expression and cellular compartmentalisation of this protein; moreover, its oligomers or protofibrils are often released to the CSF and plasma of patients. Aggregated α‐synuclein can trigger the activation of microglia; however, its capacity to induce production of specific autoantibodies (AAb) has not been assessed. In this study, we examined the presence of AAb against synuclein family members in the peripheral blood serum of PD patients and control individuals. Presence of AAb against β‐synuclein or γ‐synuclein showed no association with PD. Multi‐epitopic AAb against α‐synuclein were detected in 65% of all patients tested and their presence strongly correlated with an inherited mode of the disease but not with other disease‐related factors. The frequency of the presence of AAb in the studied group of patients with sporadic form of PD was not significantly different from the frequency in the control group but very high proportion (90%) of patients with familial form of the disease were positive for AAb against α‐synuclein. We hypothesise that these AAb could be involved in pathogenesis of the inherited form of PD.
Axonal involvement in the Wlds neuroprotective effect: analysis of pure motoneurons in a mouse model protected from motor neuron disease at a pre‐symptomatic age
Authors: Simonin Yannick , Perrin Florence E. , Kato Ann C.
Published: January 2007

The identification of the Wlds gene that delays axonal degeneration in several models of neurodegenerative disease provides an interesting tool to study mechanisms of axonal loss. We showed that crossing a mouse mutant with a motoneuron disease (pmn for progressive motor neuronopathy) with mice that express the Wlds gene delayed axonal loss, increased the life span, partially rescued axonal transport deficit and prolonged the survival of the motoneuron cell bodies. To determine factors involved in the neuroprotective effect of Wlds, we combined laser capture microdissection and microarray analysis to identify genes that are differentially regulated at a pre‐symptomatic age in motoneuron cell bodies in pmn/pmn,Wlds/Wlds mice as compared with pmn/pmn mice. Only 56 genes were de‐regulated; none of the ‘classical’ genes implicated in apoptosis were de‐regulated. Interestingly, a large proportion of these genes are related to axonal function and to retrograde and anterograde transport (i.e. members of the dynactin complex and kinesin family). These results were confirmed by real‐time PCR, in situ hybridization and at protein level in sciatic nerves. Thus, genes related to axonal function and in particular to axonal transport may be involved at an early stage in the neuroprotective property of the Wlds gene and confirm the importance of axonal involvement in this model of motor neuron disease.
Technical Note: A comparison of a novel direct ophthalmoscope, the OptyseTM, to conventional direct ophthalmoscopes
Authors: Harle Deacon E. , Davies Keri , Shah Rakhee , Hussain Syma , Cowling Susan , Panesar Tejinder K. , Bourton Jonathan , Evans Bruce J. W.
Published: January 2007

Despite the current popularity of binocular indirect ophthalmoscopy, direct ophthalmoscopes are still commonly used by clinicians for fundus examination. They are considered to be expensive, however, and it has been suggested that this cost can prevent their use by healthcare professionals in developing countries. The OptyseTM Lens Free Ophthalmoscope is a novel direct ophthalmoscope, without a lens focus system, that allows for comparatively inexpensive manufacture and supply. We compared the clarity of view with the OptyseTM to that with standard direct ophthalmoscopes, over a sequential cohort of patients with a variety of refractive errors and ocular conditions. The grade of clarity of view with the OptyseTM Lens Free Ophthalmoscope was less than conventional ophthalmoscopes (Wilcoxon signed rank test, p < 0.0001). This grade of clarity of view was not associated with the ametropia of the ophthalmoscopic observation (Spearman r ≤ 0.03, p ≥ 0.28) but was with the presence of cataracts (χ2 test, p < 0.0001) with both the OptyseTM and the conventional ophthalmoscopes. Despite its limitations, the retinal view with OptyseTM was often within acceptable clinical limits suggesting that this relatively inexpensive ophthalmoscope may have a place when cost prohibits any other type of ophthalmoscope use.
Are Modern Biological Invasions an Unprecedented Form of Global Change?
Authors: RICCIARDI ANTHONY
Published: January 2007

Abstract: The uniqueness of the current, global mass invasion by nonindigenous species has been challenged recently by researchers who argue that modern rates and consequences of nonindigenous species establishment are comparable to episodes in the geological past. Although there is a fossil record of species invasions occurring in waves after geographic barriers had been lifted, such episodic events differ markedly from human‐assisted invasions in spatial and temporal scales and in the number and diversity of organisms involved in long‐distance dispersal. Today, every region of the planet is simultaneously affected and modern rates of invasion are several orders of magnitude higher than prehistoric rates. In terms of its rate and geographical extent, its potential for synergistic disruption and the scope of its evolutionary consequences, the current mass invasion event is without precedent and should be regarded as a unique form of global change. Prehistoric examples of biotic interchanges are nonetheless instructive and can increase our understanding of species‐area effects, evolutionary effects, biotic resistance to invasion, and the impacts of novel functional groups introduced to naïve biotas. Nevertheless, they provide only limited insight into the synergistic effects of invasions and other environmental stressors, the effect of frequent introductions of large numbers of propagules, and global homogenization, all of which characterize the current mass invasion event.
The Effect of Incremental Reserve Design and Changing Reservation Goals on the Long‐Term Efficiency of Reserve Systems
Authors: STEWART ROMOLA R. , BALL IAN R. , POSSINGHAM HUGH P.
Published: January 2007

Abstract:  Selecting reserve areas based on percentages, such as 10% or 12% of a bioregion, is common in conservation planning despite widespread admission that such percentages are arbitrary and likely to be inadequate for the conservation of all biodiversity. Reserve systems based on these relatively low percentage targets are likely to require expansion in the future, resulting in the assembly of reserve systems over many years (incremental reserve design). How then will incremental reserve design, such as increasing percentage targets over time, affect the long‐term efficiency of marine reserve systems? We used South Australia as a case study to investigate how changing percentage targets affects the contribution of individual planning units to efficient reserve design. Selection frequency counts provided a measure of a planning unit's conservation value. For the majority of planning units, changing targets led to a change in their conservation value indicating, for example, that planning units identified as high‐value sites at a low‐percentage conservation target may be of lesser importance when targets are increased. Despite the variability in the value of individual planning units at different targets, there was no loss in efficiency from incremental design of reserve systems based on systematic methods compared with purpose‐built reserve systems (i.e., the system is assembled in a single iteration). The exception was when incrementally designed systems were based on South Australia's existing marine reserve system—a system developed in an ad hoc method. The result was reserve systems that were less efficient, less compact, and larger in size. This suggests that systematic approaches have an important role for efficient reserve design when there is uncertainty about the target level of reservation.
Impacts of Livestock Grazing and Tree Clearing on Birds of Woodland and Riparian Habitats
Authors: MARTIN TARA G. , McINTYRE S.
Published: January 2007

Abstract: We investigated the impact of pastoral management on birds in subtropical grassy eucalypt woodland in southeastern Queensland, Australia, where the patterns of land management have made it possible to disentangle the effects of livestock grazing from those of tree clearing. We recorded changes in bird species composition, density, and relative abundance across two woodland habitat types (riparian and nonriparian) and two levels of clearing (wooded and nonwooded) and three levels of livestock grazing (low, moderate, and high) replicated over space (1000 km2) and time (2001–2002). We predicted that species that depend on understory vegetation would be most negatively affected by livestock grazing. A Bayesian generalized linear model showed that the level of grazing had the greatest effect when trees were present. When trees were absent, the impact of grazing was overshadowed by the effects of a lack of trees. Over 65% of species responded to different levels of grazing, and the abundance of 42% of species varied markedly with habitat and grazing. The most common response to grazing was high species relative abundance under low levels of grazing (28% of species), species absence at high levels of grazing (20%), and an increase in abundance with increasing grazing (18%). Despite having similar bird assemblages, the effect of grazing was stronger in riparian habitat than in adjacent woodland habitat. Our results suggest that any level of commercial livestock grazing is detrimental to some woodland birds, particularly the understory‐dependant species, as predicted. Nevertheless, provided trees are not cleared, a rich and abundant bird fauna can coexist with moderate levels of grazing. Habitats with high levels of grazing, on the other hand, resulted in a species‐poor bird assemblage dominated by birds that are increasing in abundance nationally.
Structure‐function studies for in vitro chemical inhibition of Fcγ receptor–mediated phagocytosis
Authors: Foo Alison H. , Fletcher Stephen P. , Langler Richard F. , Porter Charlotte H. , Branch Donald R.
Published: January 2007

BACKGROUND: Previous studies [Transfusion 2005;45:384] showed that certain chemical compounds containing sulfur‐reactive groups can inhibit Fcγ receptor (FcγR)‐mediated phagocytosis in vitro. These studies, however, did not prove that only sulfur functionality–induced reactivity was efficacious. In an effort to develop a drug‐based approach for the future treatment of immune‐mediated cytopenias, these earlier findings have now been extended and this chemically induced interference with FcγR‐mediated phagocytosis of anti‐D‐coated red cells (RBCs) was examined to assess the optimal structural requirements for the inhibitory effect.

STUDY DESIGN AND METHODS: Chemical compounds were purchased or synthesized and used for the assessment of which chemical moiety(‐ies) were required for successful inhibition of in vitro phagocytosis of anti‐D‐coated RBCs with a monocyte monolayer assay.

RESULTS: Using compounds having similar structures but differences in reactive moieties, it was proved that the only chemical moiety that was required for inhibition of FcγR‐mediated phagocytosis in vitro was a disulfide bond. It is also shown, however, that a p‐nitrophenyl group provides significant enhancement to the inhibitory effect of disulfide‐containing compounds. Involvement of carbonyl and hydroxyl functional groups was also able to be ruled out.

CONCLUSION: Our results confirm and extend previous studies that suggested that only those compounds that target free sulfhydryl groups on the monocyte‐macrophage are most effective at blocking phagocytosis of antibody‐coated RBCs in vitro. It is also shown that p‐nitrophenyl substituent groups have an enhancing effect on the efficacy of disulfide bond‐containing compounds. These findings should aid in the design of a drug‐based approach for the future treatment of immune cytopenias.
Structural Characterization and Protein Adsorption Property of Hydroxyapatite Particles Modified With Zinc Ions
Authors: Hayakawa Satoshi , Ando Kanae , Tsuru Kanji , Osaka Akiyoshi , Fujii Eiji , Kawabata Koji , Bonhomme Christian , Babonneau Florence
Published: January 2007

Zinc‐containing hydroxyapatite particles (Zn/HAp) were prepared by an ion exchange reaction process involving hydroxyapatite (HAp) particles with aqueous solutions containing various amounts of zinc nitrate. The Zn2+ ion was partially substituted for the Ca2+ ion position in the HAp lattice, and hence, the obtained samples had changed little in crystallinity, particle size, and specific surface area. Adsorption of bovine serum albumin (BSA) and β2‐microglobulin (β2‐MG) in solutions containing both BSA and β2‐MG was examined. As the Zn2+ ion content in the apatites increased, the adsorbed amount of BSA was almost constant, whereas that of β2‐MG increased.
A Combined 29Si MAS NMR and Selective Dissolution Technique for the Quantitative Evaluation of Hydrated Blast Furnace Slag Cement Blends
Authors: Dyson Heather M. , Richardson Ian G. , Brough Adrian R.
Published: January 2007

Quantification of the C–S–H hydrates and anhydrous material in plain and blended cement systems can be performed by deconvolution of 29Si magic angle spinning nuclear magnetic resonance (MAS NMR) spectra. NMR data are reliable for simple cement systems, but with the incorporation of supplementary cementitious materials, quantification is often uncertain. For example, the overlap of peaks from slag cement and C–S–H in 29Si MAS NMR spectra causes problems with deconvolution. A novel method was developed to address these difficulties. 29Si MAS NMR was combined with a selective dissolution method. The hydrate peaks in slag blends can now be quantified without interference from the slag peak. This new method enables the silica remaining in unreacted slag to be estimated, thus allowing the degree of slag hydration to be quantified. Hydrate Al/Si ratios correlate well with data from analytical transmission electron microscopy (TEM). Analysis of the dissolution residues by TEM and 29Si MAS NMR indicates that they consist of a mixture of unreacted slag, a hydrotalcite‐type phase, and small amounts of aluminosilicate gel. The origin of the aluminosilicate gel needs further investigation.
Ionically Conducting Composite Membranes from the Li2O–Al2O3–TiO2–P2O5 Glass–Ceramic
Authors: Thokchom Joykumar S. , Kumar Binod
Published: January 2007

This paper reports processing of lithium ion‐conducting, composite membranes comprised of 14Li2O·9Al2O3·38 TiO2·39P2O5 glass–ceramic and polyethylene. The processing involved tape casting of 14Li2O·9Al2O3·38TiO2·39P2O5 glass powder with organic additives into tapes, subjecting the green tape to binder burnout and thermal soaking in the temperature range of 950°–1100°C, and finally infiltrating the porous tape with polyethylene solution. The ionic conductivity and microstructure of 150–350 μm thick membranes were characterized and are discussed in this paper. The crystallites of the glass–ceramic show liquid‐like conductivity at ambient temperature, whereas the grain boundary conductivity is lower by a factor of five. The lower grain boundary conductivity is explained on the basis of crystallographic mismatch and the existence of AlPO4 at the grain boundary. The polyethylene infiltration in the porous membrane improved mechanical resilience with a minor adverse effect on conductivity.
Crystallization Studies and Properties of (Ba1−xSrx)TiO3in Borosilicate Glass
Authors: Divya P.V. , Kumar V.
Published: January 2007

Ferroelectric glass–ceramics, with a basic composition (1−y)(Ba0.70Sr0.30)TiO3‐y(B2O3–x SiO2), were synthesized by sol–gel method. The major crystalline phase is the perovskite, which exhibited volume nucleation. The formation of the crystalline phase, particle size, morphology, kinetics, and mechanism of crystallization of the ferroelectric in the glass matrix have been studied using differential thermal analysis, X‐ray diffraction, and scanning electron microscopy. The kinetic parameters characterizing the crystallization of the perovskite phase have been determined using an Arrhenius model. The effect of glass content on the dielectric properties and the influence of the glass composition on the crystallization have also been investigated and are reported.
Low‐Temperature Growth of Monolayer Rutile TiO2 Nanorod Films
Authors: Wu Jin‐Ming , Qi Bin
Published: January 2007

Low‐temperature growth of well‐crystallized titania thin films with controlled nanofeatures are of great interest because of their potential uses in catalysts, gas sensors, photovoltaic cells, photonic crystals, etc. This paper reports the synthesis of a well‐crystallized, pure rutile monolayer consisting of well‐aligned nanorods with average diameters of ca. 25 nm and an aspect ratio of ca. 6 through a simple solution approach at a low temperature of 80°C. The monolayer nanorods precipitate from the precursors that were obtained through the reaction between metallic titanium and hydrogen peroxide solutions at 80°C for 24–60 h. The nanoporous titania thin layer derived by oxidizing the titanium substrate with hydrogen peroxide at 80°C for 10 min facilitates the growth of the monolayer rutile TiO2 nanorod films.
Vertical ridge augmentation with guided bone regeneration in association with dental implants: an experimental study in dogs
Authors: Simion Massimo , Dahlin Christer , Rocchietta Isabella , Stavropoulos Andreas , Sanchez Raquel , Karring Thorkild
Published: January 2007

Aim: To evaluate the effect of using guided bone regeneration (GBR) with a titanium‐reinforced e‐PTFE membrane in alveolar bone defects with titanium implants.

Material and methods: Following extraction of three mandibular premolars and a molar on both sides of the jaw in three dogs, alveolar bone defects (depth: 5–7 mm) were produced. After 4 months, three implants were inserted into each defect to a depth of approximately 4 mm, so that their coronal portion was protruding about 5 mm. Four sides in the dogs were assigned to a test group and the remaining two sides to a control group. The 12 implants in the test group were covered with a reinforced e‐PTFE membrane. The space under the membrane was filled with peripheral venous blood from the animal, and the flaps were sutured over the membrane. The six control implants received no membrane before the suturing of the flaps to complete wound closure. The animals were sacrificed after 6 months, and non‐decalcified histological specimens of the implants and surrounding tissues were prepared.

Results: Histologic and histomorphometric analyses revealed a significantly (Mann–Whitney test; P=0.08) larger amount of bone fill in the test group (mean=57.42%) than in the controls (mean=11.65%), and clinical evaluation of one test site showed that the implants were completely covered with tissue resembling bone. In most of the specimens, bone had grown in height close to, or in direct contact with the membrane. However, the new bone generally was not in direct contact with the implants. Regularly, a zone of dense connective tissue was interposed between the implants and the newly formed bone.

Conclusion: The formation of even considerable amounts of bone following vertical ridge augmentation with GBR and implants was not accompanied by predictable osseointegration of the implants.
Evaluation of student and faculty perceptions of the PBL curriculum at two dental schools from a student perspective: a cross‐sectional survey
Authors: Haghparast N. , Sedghizadeh P. P. , Shuler C. F. , Ferati D. , Christersson C.
Published: January 2007

Abstract  Problem‐based learning (PBL) research has primarily highlighted issues related to medical education and less evaluation has been reported from the field of dental education. Furthermore, literature reports tend to focus mainly on PBL from a pedagogic and curriculum constructional view and up to this date, studies from a student perspective are lacking. The aim of this study was to approach the evaluation of student and staff perceptions of PBL curricula from a student perspective at two separate schools: the Faculty of Odontology at the University of Malmö, Sweden and the dental school of the University of Southern California, School of Dentistry (USCSD), Los Angeles, CA, USA. The study was initiated and conducted by two of the authors, at the time senior students at the Faculty of Odontology in Malmö, Sweden. The study was comprised of a literature search, a 2 week field trip to USCSD, USA, survey distribution to students and faculty in both schools, analysis of the data and a written report for oral defence. The results from the survey were intended to provide feedback on student and faculty perceptions regarding the PBL curriculum. The results indicate a general student and faculty satisfaction with the PBL curriculum. Perhaps, surprisingly their perceptions did not differ significantly despite differences in geography, culture and implementation of PBL pedagogy.
Oral health behaviour and its determinants amongst Iranian dental students1
Authors: Khami Mohammad R. , Virtanen Jorma I. , Jafarian Mohammad , Murtomaa Heikki
Published: January 2007

Objectives: To study the oral health behaviour (OHB) of Iranian senior dental students in relation to their gender, background characteristics, knowledge of preventive care, and attitudes towards preventive dentistry.

Materials and methods: Using a cluster random sampling approach, a questionnaire survey was conducted with 327 senior dental students in seven dental schools. The questionnaire covered age, gender, parents’ employment in dentistry, previous academic education in dental hygiene, oral self‐care, most recent dental check‐up, knowledge of preventive dentistry and attitudes towards it. Attending a dental check‐up by a dentist or a classmate within the last year was defined as preventive care use. Chi‐square test and logistic regression models were used for statistical analyses.

Results: Women reported significantly higher frequencies of tooth brushing (P < 0.001), fluoridated toothpaste use (P = 0.001) and flossing (P < 0.001) compared with men. Respondents who had been previously educated as dental hygienists had lower frequencies of eating sugary snacks (P < 0.001) and paid more attention to preventive care (P = 0.03) than others. Those with more extensive knowledge of preventive care reported higher frequencies of using fluoridated toothpaste (P = 0.05). Reported frequencies of brushing were higher amongst those with more positive attitudes (P = 0.03). In logistic regression models, having at least one parent employed as a dentist was significantly associated with higher frequencies of eating sugary snacks (P = 0.047, OR = 0.3) and more frequent preventive care use (P = 0.048, OR = 2.9).

Conclusion: Education and training in preventive measures should be effective enough to overcome background characteristics. There is room for improving the OHB of Iranian dental students.
The effect of a community dental service outreach programme on the confidence of undergraduate students to treat children: a pilot study
Authors: Hunter M. Lindsay , Oliver Richard , Lewis Rosamund
Published: January 2007

Objective:  To examine the effect of a community dental service (CDS) outreach teaching programme on undergraduates’ confidence to undertake a range of paediatric dental procedures.

Method:  Eighteen final year dental students completed a questionnaire prior to, and following participation in an outreach teaching programme. At each time point, the students were asked to identify how confident they felt to carry out a range of procedures commonly encountered in the treatment of children, employing a Likert scale modified to comprise six points where a rating of 1 represented ‘not at all confident’ and a rating of 6 ‘very confident’.

Results:  The distribution of scores at each time point indicated that students were more confident to carry out each of the listed procedures following participation in the outreach teaching programme than they had been on completion of their paediatric dentistry sessions within the School of Dentistry. At the individual student level, 16 of the 18 students indicated that they were, overall, more confident following their placement than previously.

Conclusions:  It can be concluded that the long‐established CDS outreach teaching programme run by the School of Dentistry, Wales College of Medicine in conjunction with the staff of Cardiff and Vale NHS Trust is a valuable adjunct to undergraduate teaching in paediatric dentistry.