bluuebunny/crossref_metadata_2025 huggingface dataset:
Examination of outcome following abdominoperineal resection for adenocarcinoma in Oxford
Authors: Chambers W. , Khan A. , Waters R. , Lindsey I. , George B. , Mortensen N. , Cunningham C.
Published: June 2009

Aim  Abdominoperineal resection (APR) has been shown to have poor outcomes compared with anterior resection (AR) in the treatment of rectal cancer. We compared APR outcomes with those for low AR.

Method  Lower third rectal cancers treated at the John Radcliffe Hospital with APR and low AR were examined using a prospectively collected database augmented with review of patient records. For all cases (APR and low AR), a range of patient, cancer and outcome data were collected. A selected group was created on the basis of exclusions. Outcomes for the global and selected APR and low AR groups were compared using the Kaplan–Meier method. CRM+ve and CRM−ve APR cases were compared.

Results  Between 1994 and 2003, 70 APR and 93 low AR were performed. After exclusions, 42 APR and 81 low AR remained. Median follow‐up was 4.8 years. Five year survival for the APR group was significantly worse than for the low AR group. The APR group showed significantly fewer T0 cancers and significantly more T3 cancers. CRM R1 involvement was significantly higher for the APR group. The CRM+ve APR group contained significantly more later stage cancers, more defective resection specimens, more abscesses and fistulas and was associated with more local recurrence.

Conclusions  These data showed that APR led to worse results than low AR in terms of overall survival and circumferential margin involvement, but that the cancers treated with APR tended to be more locally advanced.
Stoma‐related complications and stoma size – a 2‐year follow up
Authors: Persson E. , Berndtsson I. , Carlsson E. , Hallén A.‐M. , Lindholm E.
Published: June 2009

Aim  The purpose of the study was to prospectively describe stoma configuration and evaluate stoma‐related complications and their association with possible risk factors.

Method  All elective patients (n = 180) operated on with a formation of colostomy, ileostomy or loop‐ileostomy between 2003 and 2005 were included in the study. Follow up took place on the ward postoperatively and five times during 2 years after discharge. On these occasions the diameter and height of the stoma were recorded. Complications such as peristomal skin problems, necrosis, leakage caused by a low stoma, stenosis, granuloma formation, prolapse and peristomal hernia formation were evaluated.

Results  Most complications occurred 2 weeks after discharge; 53% of patients with colostomies, 79% with loop‐ileostomies and 70% of patients with end‐ileostomy had one or more complications. The most common complication was skin problems and it was most common in patients with end‐ileostomies (60%) and loop‐ileostomies (73%). Postoperatively at ward review, the most common complication was necrosis, which occurred in 20% of patients with a colostomy. Granuloma formation was most frequent in colostomies. Almost all patients with an end‐ileostomy and loop‐ileostomy with a height lower than 20 mm had leakage and skin problems as had half of the patients with a colostomy height lower than 5 mm.

Conclusion  To prevent stoma‐related complications, it is important to produce an adequate height of the stoma, with early and regular follow ups and adjustment of the appliance. To work closely in collaboration with the colorectal surgeons is of utmost important to provide feedback and in turn, to improve stoma outcome.
Management of hypertension in patients with diabetes: the place of angiotensin‐II receptor blockers
Authors: Kalaitzidis Rigas , Bakris George
Published: June 2009

Hypertension is an important cardiovascular (CV) risk factor in patients with diabetes mellitus. In this setting, tight control of blood pressure (BP) significantly reduces CV morbidity and mortality. In the UK Prospective Diabetes Study, a 10 mmHg reduction in systolic blood pressure (SBP) was superior to a 0.7% decrease in glycosylated haemoglobin A1c (HbA1c) as far as reducing morbidity and mortality was concerned. In the Hypertension Optimal Treatment study, the risk of CV events decreased by 51% among patients with type 2 diabetes randomized to the lower BP level. Based on these findings, contemporary treatment guidelines recommend a target SBP/diastolic blood pressure of <130/80 mmHg for patients with diabetes.
Soraphen, an inhibitor of the acetyl‐CoA carboxylase system, improves peripheral insulin sensitivity in mice fed a high‐fat diet
Authors: Schreurs M. , Van Dijk T. H. , Gerding A. , Havinga R. , Reijngoud D.‐J. , Kuipers F.
Published: June 2009

Aim: Inhibition of the acetyl‐CoA carboxylase (ACC) system, consisting of the isozymes ACC1 and ACC2, may be beneficial for treatment of insulin resistance and/or obesity by interfering with de novo lipogenesis and β‐oxidation. We have evaluated effects of pharmacological inhibition of ACC by soraphen (SP) on high fat (HF) diet–induced insulin resistance in mice.

Method: Male C57Bl6/J mice were fed control chow, a HF diet or a HF diet supplemented with SP (50 or 100 mg/kg/day).

Results: Body weight gain and total body fat content of SP‐treated animals were significantly reduced compared with HF‐fed mice. Fractional synthesis of palmitate was significantly reduced in mice treated with SP, indicative for ACC1 inhibition. Plasma β‐hydroxybutyrate levels were significantly elevated by SP, reflecting simultaneous inhibition of ACC2 activity. Mice treated with SP showed improved peripheral insulin sensitivity, as assessed by hyperinsulinaemic euglycaemic clamps.

Conclusion: Pharmacological inhibition of the ACC system is of potential use for treatment of key components of the metabolic syndrome.
Transformational Leadership and Employee Well‐Being: The Mediating Role of Trust in the Leader and Self‐Efficacy
Authors: Liu Jiayan , Siu Oi‐Ling , Shi Kan
Published: June 2009

Although transformational leadership (TL) is considered a kind of positive leadership, which can elevate followers in the long term, the mechanism of how TL influences employee well‐being remains a relatively untouched area. Based on survey data collected from 745 employees from the People's Republic of China (Beijing, n= 297; Hong Kong, n= 448), results revealed that employees' trust in the leader and self‐efficacy partially mediated the influence of TL on job satisfaction, and fully mediated the influence of TL on perceived work stress and stress symptoms. Implications of these findings for research and practice are discussed.

Bien que le leadership transformationnnel (TL) soit considéré comme une sorte de leadership positif qui peut faire progresser les suiveurs sur le long terme, le mécanisme par lequel TL contribue à leur bien être reste relativement inexploré. Les résultats basés sur des données collectées auprès d’un échantillon de 745 employés de la République Populaire de Chine (Beijin, n = 297; Hong Kong, n = 448), montrent que la confiance des suiveurs dans le leader et l’auto‐efficacité sont en partie dus à l’influence du TL sur la satisfaction au travail et sont entièrement dus à l’influence du TL sur le stress perçu au travail et les symptômes de stress. Les implications de ces résultats pour la recherche et la pratique sont discutées.
In defence of the indefensible: an alternative to John Paley's reductionist, atheistic, psychological alternative to spirituality
Authors: Nolan Steve
Published: June 2009

John Paley has rightly observed that, while spirituality is widely discussed in the nursing literature, the discussions are uncritical and unproblematic. In an effort ‘to reconfigure the spirituality‐in‐nursing debate, and to position it where it belongs: in the literature on health psychology and social psychology, and not in a disciplinary cul‐de‐sac labelled “unfathomable mystery” ’, Paley has proposed an alternative, reductionist approach to spirituality. In this paper, I identify two critiques developed by Paley: one political, the other ‘logical’. Paley's political critique claims the concept of ‘spirituality’ has been appropriated by nursing theorists as part of an attempt to accrue professional power and jurisdiction over occupational territory. I suggest that Paley's analysis masks his own exclusivist, secularizing jurisdictional claim made at the expense of spirituality. Paley's so‐called ‘logical’ critique is motivated by an intention to ‘determine what the “spirituality” terrain looks like from the naturalistic point of view’. However, noting a number of inconsistencies, I challenge his ‘logical move’ as a naïve attack on a straw man. In place of Paley's reductionism, I propose my own alternative alternative and argue (after Foucault) that ‘spirituality’ is a discourse, a non‐reductionist attempt, in a post‐religious society, to speak about the human condition open to the unknown. I conclude with a definition and a description of empirically congruent spirituality.
Social structure and nursing research
Authors: Nairn Stuart
Published: June 2009

The concept of social structure is ill defined in the literature despite the perennial problem and ongoing discussion about the relationship between agency and structure. In this paper I will provide an outline of what the term social structure means, but my main focus will be on emphasizing the value of the concept for nursing research and demonstrate how its erasure in some research negatively effects on our understanding of the nurses' role in clinical practice. For example, qualitative research in nursing has largely focused on agency through such theories as phenomenology, hermeneutics, and symbolic interactionism. The result is that social structure may be erased or seen as epiphenomena of agency. My purpose is to provide a theoretical discussion of social structure and how such a discussion can help us to understand how nurses live and experience clinical practice. While not denying the importance of agency, I will argue that the thinned out approach to social structure places limits on our understanding of the constraints nurses experience in their working lives. The result is that nurses' attitudes and clinical failings are individualized, resulting in ever more calls for improved education, when a more thorough examination of structural issues may elucidate more fundamental problems.
Cultural safety and the challenges of translating critically oriented knowledge in practice
Authors: Browne Annette J. , Varcoe Colleen , Smye Victoria , Reimer‐Kirkham Sheryl , Lynam M. Judith , Wong Sabrina
Published: June 2009

Cultural safety is a relatively new concept that has emerged in the New Zealand nursing context and is being taken up in various ways in Canadian health care discourses. Our research team has been exploring the relevance of cultural safety in the Canadian context, most recently in relation to a knowledge‐translation study conducted with nurses practising in a large tertiary hospital. We were drawn to using cultural safety because we conceptualized it as being compatible with critical theoretical perspectives that foster a focus on power imbalances and inequitable social relationships in health care; the interrelated problems of culturalism and racialization; and a commitment to social justice as central to the social mandate of nursing. Engaging in this knowledge‐translation study has provided new perspectives on the complexities, ambiguities and tensions that need to be considered when using the concept of cultural safety to draw attention to racialization, culturalism, and health and health care inequities. The philosophic analysis discussed in this paper represents an epistemological grounding for the concept of cultural safety that links directly to particular moral ends with social justice implications. Although cultural safety is a concept that we have firmly positioned within the paradigm of critical inquiry, ambiguities associated with the notions of ‘culture’, ‘safety’, and ‘cultural safety’ need to be anticipated and addressed if they are to be effectively used to draw attention to critical social justice issues in practice settings. Using cultural safety in practice settings to draw attention to and prompt critical reflection on politicized knowledge, therefore, brings an added layer of complexity. To address these complexities, we propose that what may be required to effectively use cultural safety in the knowledge‐translation process is a ‘social justice curriculum for practice’ that would foster a philosophical stance of critical inquiry at both the individual and institutional levels.
Applying Antonio Gramsci's philosophy to postcolonial feminist social and political activism in nursing
Authors: Racine Louise
Published: June 2009

Through its social and political activism goals, postcolonial feminist theoretical approaches not only focus on individual issues that affect health but encompass the examination of the complex interplay between neocolonialism, neoliberalism, and globalization, in mediating the health of non‐Western immigrants and refugees. Postcolonial feminism holds the promise to influence nursing research and practice in the 21st century where health remains a goal to achieve and a commitment for humanity. This is especially relevant for nurses, who act as global citizens and as voices for the voiceless. The commitment of nursing to social justice must be further strengthened by relying on postcolonial theories to address issues of health inequities that arise from marginalization and racialization. In using postcolonial feminist theories, nurse researchers locate the inquiry process within a Gramscian philosophy of praxis that represents knowledge in action.
A Semiparametric Analysis of the Term Structure of the US Interest Rates*
Authors: Iacone Fabrizio
Published: June 2009

The short end of the US$ term structure of interest rates is analysed allowing for the possibility of fractional integration and cointegration. This approach permits mean‐reverting dynamics for the data and the existence of a common long run stochastic trend to be maintained simultaneously. We estimate the model for the period 1963–2006 and find it compatible with this structure. The restriction that the data areI(1) and the errors areI(0) is rejected, mainly because the latter still display long memory. This result is consistent with a model of monetary policy in which the Central Bank operates affecting contracts with short term maturity, and the impulses are transmitted to contracts with longer maturities and then to the final goals. However, the transmission of the impulses along the term structure cannot be modelled using the Expectations Hypothesis.
The Origins of American Power in Iraq, 1941–1945
Authors: O'Sullivan Christopher , Damluji Manaf
Published: June 2009

Utilizing archival sources in both the United States and Britain to describe the changes in American policy in Iraq during World War II, and tracing the emergence of the United States as an important factor in Iraq's politics and history, the authors challenge the notion that the United States was a passive bystander to events there during the war. Washington initially followed the British lead, but, beginning in 1942, the United States became more assertive in its relations with Iraq, with American diplomats, State Department officials, postwar planners, and intelligence officers promoting the ideals of the Atlantic Charter while simultaneously aiming to secure Iraq's petroleum and tying it into a network of Western alliances. Iraq's vital strategic position and its rich petroleum resources made it an important part, along with Saudi Arabia and Iran, of the American effort to secure, militarily and economically, the oil‐rich Gulf region for the West in the postwar era.
(En)Gendering Responsibilities: Experiences of Parenting a ‘Young Offender’
Authors: HOLT AMANDA
Published: June 2009

Abstract: This article discusses how parenting a ‘young offender’ involves specific additional responsibilities for parents who are already under scrutiny for apparently not taking their parenting responsibilities seriously. With reference to empirical data, three specific parental tasks are considered: managing the family's involvement in the youth justice system, waiting on ‘standby’ for police and schools, and reporting the child's offences to the police. In doing so, this article highlights the ways in which gender is implicated, and performs a regulatory function, in the day‐to‐day lives of mothers and fathers who are parenting a ‘troublesome’ child.
Does the NOMS Risk Assessment Bubble Need to Burst for Prisoners Who May be Innocent to Make Progress?
Authors: NAUGHTON MICHAEL
Published: June 2009

Abstract: This article considers, critically, a new course for prison and probation staff who work with indeterminate sentenced prisoners (ISPs) that has been devised by the National Offender Management Service (NOMS), which allows, for the first time, the possibility that some prisoners maintaining innocence may be innocent. However, whilst on its face this looks like a significant step, a closer analysis shows that the rationale and operations of the NOMS system of risk assessment for prisoners maintaining innocence remains trapped in a bubble which deters meaningful assistance to prisoners who may be innocent. As such, prisoners maintaining innocence continue to be faced with the ‘parole deal’, a situation whereby they claim that they must choose to admit their guilt for crimes that they say that they did not commit in order to make progress through the prison system and obtain their release.
Disability, Minority, and Difference
Authors: BARNES ELIZABETH
Published: June 2009

abstract

In this paper I develop a characterization of disability according to which disability is in no way a sub‐optimal feature. I argue, however, that this conception of disability is compatible with the idea that having a disability is, at least in a restricted sense, a harm. I then go on to argue that construing disability in this way avoids many of the common objections levelled at accounts which claim that disability is not a negative feature.
Identifying Putative Promoter Regions of Hermansky‐Pudlak Syndrome Genes by Means of Phylogenetic Footprinting
Authors: Stanescu Horia , Wolfsberg Tyra G. , Moreland R. Travis , Ayub Mariam H. , Erickson Elizabeth , Westbroek Wendy , Huizing Marjan , Gahl William A. , Helip‐Wooley Amanda
Published: June 2009

HPS is an autosomal recessive disorder characterized by oculocutaneous albinism and prolonged bleeding. Eight human genes are described resulting in the HPS subtypes 1–8. Certain HPS proteins combine to form Biogenesis of Lysosome‐related Organelles Complexes (BLOCs), thought to function in the formation of intracellular vesicles such as melanosomes, platelet dense bodies, and lytic granules. Specifically, BLOC‐2 contains the HPS3, HPS5 and HPS6 proteins. We used phylogenetic footprinting to identify conserved regions in the upstream sequences of HPS3, HPS5 and HPS6. These conserved regions were verified to have in vitro transcription activation activity using luciferase reporter assays. Transcription factor binding site analyses of the regions identified 52 putative sites shared by all three genes. When analysis was limited to the conserved footprints, seven binding sites were found shared among all three genes: Pax‐5, AIRE, CACD, ZF5, Zic1, E2F and Churchill. The HPS3 conserved upstream region was sequenced in four patients with decreased fibroblast HPS3 RNA levels and only one HPS3 mutation in the coding exons and surrounding exon/intron boundaries; no mutation was found. These findings illustrate the power of phylogenetic footprinting for identifying potential regulatory regions in non‐coding sequences and define the first putative promoter elements for any HPS genes.
Seasonal pattern of depth selection in smallmouth bass
Authors: Suski C. D. , Ridgway M. S.
Published: June 2009

The current study used a stationary acoustic telemetry array to monitor the depth selection of adult smallmouth bass Micropterus dolomieu in a large, oligotrophic lake in Ontario, Canada. At an annual scale, smallmouth bass demonstrated regular, seasonal changes in inhabited depths: fish occupied shallow water during the summer (2–5 m depth) and descended to deeper water (12–15 m depth) during winter under ice. Smallmouth bass remained above the thermocline in the summer, seasonal depth patterns did not vary across fish size and movements to and from seasonal depths were closely linked to the development and degradation of the thermocline. At finer time scales, smallmouth bass exhibited diel vertical migrations in summer, with fish moving to <2 m at night, and then descending to 3–5 m during the day. This pattern remained constant during the summer period examined, and varied with size such that larger fish remained deeper than smaller fish. During winter, depth did not vary across the 3‐month monitoring period (c. 14 m), but small (<2 m) changes in depth were observed periodically, suggesting limited movements were occurring. Results are further discussed in the context of climate change and reproductive success for this species.
Quantitative genetics parameters show partial independent evolutionary potential for body mass and metabolism in stonechats from different populations
Authors: Tieleman B. I. , Versteegh M. A. , Helm B. , Dingemanse N. J.
Published: June 2009

Phenotypic variation in physiological traits, such as energy metabolism, is commonly subjected to adaptive interpretations, but little is known about the heritable basis or genetic correlations among physiological traits in non‐domesticated species. Basal metabolic rate (BMR) and body mass are related in complex ways. We studied the quantitative genetics of BMR, residual BMR (on body mass), mass‐specific BMR and body mass of stonechats originating from four different populations and bred in captivity. Heritabilities ranged from 0.2 to 0.7. The genetic variance–covariance structure implied that BMR, mass‐specific BMR and body mass can in part evolve independently of each other, because we found genetic correlations deviating significantly from one and minus one. BMR, mass‐specific BMR and body mass further differed among populations at the phenotypic level; differences in the genetic correlation among populations are discussed.
Ecological factors regulating brood attendance patterns of the Western Sandpiper Calidris mauri
Authors: RUTHRAUFF DANIEL R. , KELLER JULIETTE N. , RIZZOLO DANIEL J.
Published: June 2009

Parental brood attendance patterns vary greatly among shorebird species. For monogamous calidridine species, biparental care with female‐first brood departure is most common. It is believed that adult sandpipers balance potential individual survival costs associated with extended parental care against the benefit gained by their brood of prolonged parental care. These costs and benefits are difficult to quantify and factors affecting the termination of parental brood attendance are unclear. We compared clutch size, nesting phenology, and parental attendance patterns of Western Sandpipers Calidris mauri at Nome and Kanaryarmiut, Alaska, sites separated by three degrees of latitude. The sites differed in breeding density and duration of breeding season, but the distribution of clutch sizes did not differ between sites or between nesting attempts. Parental attendance patterns were similar between sites, suggesting that parental attendance is a highly conserved life‐history trait in Western Sandpipers. Male Western Sandpipers attended broods longer than females, and the duration of parental attendance decreased at a similar rate for both sexes as the season progressed. Male and female Western Sandpipers undertake differential migrations to their non‐breeding grounds, with males typically settling at more northerly locations and females at more southerly sites, a migration pattern shared by certain other monogamous calidridine species. These same species exhibit similar parental brood attendance patterns, suggesting the strong role of overall migration distance in shaping the expression of parental attendance behaviours. A contrast of more geographically disjunct sites coupled with a better understanding of the migratory connectivity between Western Sandpiper breeding and non‐breeding populations would elucidate the role of cross‐seasonal effects on parental brood attendance decisions.
Magellanic Penguin eggshell pores: does number matter?
Authors: BOERSMA P. DEE , REBSTOCK GINGER A.
Published: June 2009

Most penguin species lay two eggs 3–4 days apart that hatch 1–2 days apart. Hypotheses to explain the shorter incubation period for the second egg include differences in porosity of the eggshells. Eggs with more or larger pores and/or thinner shells have higher gas exchange rates and faster embryonic development. We used eggshells from hatchling Magellanic Penguins Spheniscus magellanicus to test whether eggshell thickness and pore density affect incubation period. We expected: (i) second eggs to have thinner shells and/or more pores than first eggs; (ii) eggs to have thinner shells and/or more pores if they were laid by older females, later in the season, or in burrow nests (more humid than open nests under bushes). We found no support for these hypotheses. Egg pores and shell thickness were not related to incubation period. Eggs from the same clutch were similar in eggshell thickness and pore density. Female age, laying date and nest type were poor predictors of eggshell thickness and pore density. Egg pores, we conclude, have little explanatory power for differences in incubation time of eggs in Magellanic Penguins, and suggest that synchronous onset of incubation matters.
Variation in effects of male plumage ornaments: the case of Iberian Pied Flycatchers
Authors: GALVÁN ISMAEL , MORENO JUAN
Published: June 2009

It has been proposed that mate preferences by female Pied Flycatchers Ficedula hypoleuca differ between southern (Iberian) and northern (Scandinavian) European populations. Whereas the size of the white forehead patch, but not plumage colour, has been reported to be a sexually selected trait in the former, only plumage darkness apparently acts as an ornament in the latter. In addition, northern male Pied Flycatchers become darker with age, a trend not detected until the present study in southern birds. Here we show that in an Iberian population of Pied Flycatchers breeding only a few tens of kilometres from previously studied populations, plumage darkness is associated with mating success and increases with age, whereas the size of the white forehead patch is not related to mating success and is only weakly correlated with age, trends similar to those reported for Scandinavian rather than other Iberian Pied Flycatcher populations. This represents a case of variation in sexually selected traits between geographically close populations of Pied Flycatchers that cannot be explained by sympatry with closely related species. It is proposed that differences in the identity and abundance of environmental stressors may be the cause of this regional variation in sexually selected traits.
Microwave Disinfection of Complete Dentures Contaminated In Vitro with Selected Bacteria
Authors: Dovigo Lívia Nordi , Pavarina Ana Cláudia , Ribeiro Daniela Garcia , De Oliveira Juliana Aparecida , Vergani Carlos Eduardo , Machado Ana Lucia
Published: June 2009

Purpose: This study evaluated the effectiveness of microwave irradiation for disinfection of simulated complete dentures.

Materials and Methods: Seventy dentures were fabricated in a standardized procedure, subjected to ethylene oxide sterilization, individually inoculated (107 cfu/mL) with Staphylococcus aureus (n = 20), Pseudomona aeruginosa (n = 20), and Bacillus subtilis (n = 30) and incubated for 24 hours at 37°C. After that, 40 dentures were selected for microwaving. For each microorganism, 10 dentures were submitted to microwave irradiation at 650 W for 3 minutes. In addition, 10 dentures contaminated with B. subtilis were irradiated for 5 minutes. Thirty non‐microwaved dentures (n = 10 for each bacteria) were used as positive controls. Replicate aliquots (25 μL) of suspensions were plated at dilutions of 10−3 to 10−6 on plates of selective media appropriate for each organism. After incubation (37°C for 48 hours), colonies were counted (cfu/mL). TSB beakers with the microwaved dentures were incubated at 37°C for a further 7 days to verify long‐term disinfection. The data were statistically analyzed by the Kruskal‐Wallis test (α= 0.05).

Results: No evidence of growth was observed at 48 hours for S. aureus and P. aeruginosa on plates, and no turbidity was visible in the TSB beakers of these specimens after 7 days of incubation. Dentures contaminated with B. subtilis and irradiated for 3 minutes produced microbial growth on six plates and turbidity on all TSB beakers. Microwaving for 5 minutes resulted in survival of B. subtilis in two plates and two beakers.

Conclusion: Microwave irradiation for 3 minutes at 650 W produced sterilization of complete dentures contaminated with S. aureus and P. aeruginosa. Dentures contaminated with B. subtilis were disinfected by microwave irradiation after 3 and 5 minutes at 650 W.
Finite Element Stress Analysis of Diastema Closure with Ceramic Laminate Veneers
Authors: Chander N. Gopi , Padmanabhan T. V.
Published: June 2009

Purpose: The purpose of this study was to use finite element stress analysis to examine the relative importance of variables such as porcelain laminate veneer (PLV) extensions, loading angle, and loading level for the case of feldspathic ceramic veneering of teeth to manage diastema.

Materials and Methods: A 3D maxillary central incisor including its internal anatomy and morphology was constructed with ANSYS software for different extensions of PLV. Internal boundaries defining the dentinoenamel junction, the pulp‐dentinal junction, the interface between the enamel‐luting cement, and the porcelain‐luting cement were well defined. The von Mises stresses distribution and stress intensity were analyzed on the free extension of PLV for varying extensions, various angulations (0°, 30°, and 60°) on the incisal edge, and for different loading levels (50, 150, and 250 N).

Results: The numerical values of stress were recorded. A significant difference in stress was observed. Increased stresses occurred with increased extensions, angulations, and loading levels. At 0° angulation, compressive stresses were visualized in finite element analysis for various magnitudes of force. Higher stress values of 182 MPa and 211 MPa were obtained for the 2.5‐mm extension in the mesial surface and in both proximal surfaces for 0° angulation at 250 N magnitude of force. The stress occurring at 30° and 60° angulations was the combination of compressive and tensile stress. Higher values of 261 MPa and 232 MPa were observed when forces were applied on the mesial extension of the PLV and on both the proximal surfaces for 2.5 mm at 30°, 250 N magnitude of force. A maximum stress value of 507 MPa was observed when PLV were increased in mesial width by 2.5 mm for 60° angulation at 250 N magnitude of force.

Conclusion: The extensions of PLV in diastema closure have more of an esthetic than functional consideration, but critical factors such as angulations and the loading level acting on the free extension of PLV are important.
Adhesive Bonding of Resin Composite to Various Ni‐Cr Alloy Surfaces Using Different Metal Conditioners and a Surface Modification System
Authors: Almilhatti Hercules Jorge , Giampaolo Eunice Teresinha , Vergani Carlos Eduardo , Machado Ana Lucia , Pavarina Ana Claudia , Betiol Éderson Áureo Goncalves
Published: June 2009

Purpose: This study evaluated the effect of three metal conditioners [Metal Photo Primer® (MPP), Cesead II Opaque Primer® (OP), Targis Link® (TL)], and one surface modification system [Siloc® (S)] on the shear bond strength (SBS) of a prosthetic composite material to Ni‐Cr alloy.

Materials and Methods: Rivet‐shaped specimens were cast, and three surface treatments were evaluated: Polishing (P); sandblasting with either 50 μm (50SB) or 250 μm (250SB) Al2O3. All products were applied to half of the specimens, while the other half remained without the materials. Veneering resin composite (8‐mm diameter, 2‐mm thick) was applied and light‐exposed for 90 seconds in a laboratory light‐curing unit. The specimens were stored in water at 37°C for 24 hours, and half were subjected to 500 thermal cycles consisting of water baths at 4°C and 60°C. All specimens were submitted to SBS test (0.5 mm/min) until failure. Failure patterns were determined using optical and scanning electron microscope (SEM) analysis. Data were analyzed by ANOVA and post hoc Tukey's test (preset alpha of 5%).

Results: The SBS values of OP and TL groups were higher than those of MPP and S within the 50SB treatment (p < 0.05). No significant difference in SBS was noted between OP and TL as well as between MPP and S. On the other hand, no significant differences were found among conditioners within the 250SB group (p > 0.05). The SBS values of MPP, OP, and S from the 250SB group were higher than those from 50SB (p < 0.05). No significant difference in SBS was noted among most groups with conditioners after thermocycling. The only exception was observed for MPP, which showed an increase in SBS after thermocycling (p < 0.05). Differences in SBS were noted among the groups with conditioners (p < 0.05), and no significant difference in SBS was noted between TL and OP groups, which showed the highest values among all within the P group. No significant difference was noted between MPP and S. Debonded surfaces showed adhesive failures predominantly located between metal surface and opaque resin.

Conclusions: The OP and TL conditioners and surface sandblasting with 250 μm Al2O3 promoted the highest SBS between resin and the Ni‐Cr metal surface.
A Preliminary Survey of Impression Trays Used in the Fabrication of Fixed Indirect Restorations
Authors: Mitchell Sonya T. , Ramp Merrie H. , Ramp Lance C. , Liu Perng‐Ru
Published: June 2009

Purpose: A variety of impression trays are used in the fabrication of fixed indirect restorations. Impressions used in the construction of fixed indirect restorations were examined for tray type, manner of use, and overall impression quality.

Materials and Methods: A commercial dental laboratory provided 1403 impressions used to fabricate fixed indirect restorations during a 3‐month period. Impressions were examined for tray type, quantity and type of recorded abutments, the impression of intact teeth adjacent to and opposing the abutment, the presence of the canine in the impression, and an assessment of the quality of the impression.

Results: A majority of trays examined were plastic (864, or 61.6%). Dual‐arch trays comprised 73.1% of the total. Most of these were metal posterior (n = 499) or plastic posterior (n = 280). Among partial dual‐arch impressions, 561 (55.7%) were for the single abutment restoration, bounded by intact teeth anterior and posterior, and with an intact opposing tooth. Eleven percent of plastic dual‐arch impressions failed to register the canine. Regarding restoration type, there were 955 impressions for the single‐tooth crown, 46 for implant‐supported restorations, and 11 for veneers. Twenty impressions were for posts, inlays, or onlays. Impressions for multiple single‐tooth crowns and fixed partial dentures comprised the remainder. In terms of overall quality, 85.3% of impressions were excellent or good. The lowest performance in terms of excellent quality was in the anterior plastic single‐arch impression (44.8%), whereas the best rate of excellent quality noted was for the posterior dual‐arch impression (82.4%).

Conclusions: Within the limitations of this study, dual‐arch trays were the most commonly used tray. Recommendations for the use of the dual‐arch tray were not followed in a substantial number of impressions examined.
Return to the Origin: Negotiating the Modern and Unmodern in the Old City of Damascus
Authors: TOTAH FAEDAH M.
Published: June 2009

The 2002 government restoration of Suq in Damascus led to disagreements between officials and merchants over acceptable spatial practice in the marketplace. Though both were vested in the Suq's introduction to the historic Old City, they had different interpretations of this role. Officials emphasized a sanitized and ordered space whereas merchants focused on the commercial activities necessary in the marketplace over discipline. Eventually both interpretations, though at times contradictory, were included in the project. This article illustrates how the replication of modernity in a public space with inherent contradictions is a result of negotiations between formal and informal modernitites.
Modernity, Tradition and Nuances of Class in Lesotho
Authors: TURKON DAVID
Published: June 2009

Anthropological studies of identity commonly focus on culture, religion and ethnicity as bases for self identification and affiliation. This focus has come at the expense of broader foci such as class. Based on fieldwork in culturally homogeneous Lesotho, in this article I demonstrate how, in the wake of economic and political modernization, class consciousness has become a salient criteria for identity formation among Basotho in ways that are linguistically marked and culturally reconciled. Analyzing class consciousness provides a framework for understanding ways that urban, state, regional and global ideologies inform rural culture. Social scientists, especially anthropologists, should compliment post‐modern analysis of incommensurable social identities with class analysis, as a basis for analyzing the cross cultural effects of modernization in national as well as localized settings.
Normalizing Christiania: Project Clean Sweep and the Normalization Plan in Copenhagen
Authors: AMOUROUX CHRISTA
Published: June 2009

In 1971 a group of activists moved into a vacated military base near downtown Copenhagen and created an oppositional community. Named “Christiania,” this community began as a squat and is now a thriving community of artists, academics, activists and self‐labeled social losers. For thirty‐eight years Christiania has been a space of cultural critique and alterity in the center of Copenhagen. However, in 2002 the newly elected neoliberal‐conservative government decided to “normalize” Christiania by privatizing its cooperative businesses and communally owned housing. Within this specific historical context, I present normalization as a strategy where coercive, spatial and rhetorical practices are employed by the state in order to legitimize Christiania's closure. A police raid and a state report are used as examples of how Foucault's notion of normalization is enacted “on the ground” in a contemporary historical context, and how normalization is responded to by Christiania's residents.
“But They are Like You and Me”: Gay Civil Servants and Citizenship in a Cosmopolitanizing Singapore
Authors: TAN CHRIS K.K.
Published: June 2009

In July 2003, Singapore's then‐Prime Minister triggered public outrage by declaring that the state would now employ openly gay Singaporeans as civil servants. Besides questioning how such a seemingly inconsequential statement could generate such controversy, I also interrogate why the state had reversed its previously homophobic stance. I argue that, as a city‐state with aspirations to become a global city, Singapore attempted to market the “difference” of its sexual minorities to appear cosmopolitan and attractive to the “creative class” of professional labor. By contradicting the sexual exclusivity inherent in normative notions of citizenship, however, this cosmopolitanizing drive triggered the moral outrage. Furthermore, I assert that despite its apparent message of tolerance, the state's declaration remained an empty marketing ploy. While it has enabled homosexual Singaporeans to assess their status as citizens, the state has neither legalized it nor struck down existing anti‐sodomy legislation that fundamentally contradicts it. By exposing the declaration as only an exploitative façade that discursively conscripted gay and lesbian Singaporeans into cosmopolitanizing the country for the state, I highlight the limits of discourses of difference in Singapore.
Uniaxial Freezing, Freeze‐Drying, and Anodization for Aligned Pore Structure in Dye‐Sensitized Solar Cells
Authors: Khaleghi Evan , Olevsky Eugene , Meyers Marc
Published: June 2009

A variety of methods are available for creating the titanium dioxide (TiO2) semiconductor surface layer of dye‐sensitized solar cells (DSSCs); however, many of them are used independently to create surface morphologies that are influenced by only one process. A series of experimental techniques are utilized, some not originally used for thin film preparation, to create a semiconductor surface that exhibits variations in morphology on the macro‐, micro‐, and nanoscales. The techniques used to create the micro‐ and nanostructures are uniaxial freezing, freeze‐drying, and anodization or etching, combined with the macrostructural techniques of the doctor blade method, screen printing, and/or electrophoretic deposition. When several of these techniques are used together to create, and modify, a thin film for DSSC, these techniques can produce a TiO2 semiconductor layer for DSSC that has very high current and voltage characteristics, and a surface morphology more complex than can be created by using any one of the techniques alone.
Sintering Mechanisms of Zirconium and Hafnium Carbides Doped with MoSi2
Authors: Silvestroni Laura , Sciti Diletta , Kling Jens , Lauterbach Stefan , Kleebe Hans‐Joachim
Published: June 2009

The microstructure of two pressureless‐sintered ultra‐high‐temperature ceramics, namely ZrC+20 vol% MoSi2 and HfC+20 vol% MoSi2, was characterized by scanning and transmission electron microscopy. With regard to the ZrC–MoSi2 system, ZrxSiy compounds and SiC were detected. In the HfC–MoSi2 system, a mixed phase was detected at the triple points and identified as (Mo,Hf)5Si3. For both the systems investigated, the high wettability of the silicide‐based phases on the matrix grains suggests that sintering is assisted by a liquid phase. This contribution reports for the first time on the sintering mechanisms of early transition metal carbides doped with MoSi2 as a sinter additive, on the basis of the microstructural evolution observed upon sintering and in the light of phase diagrams and thermodynamical calculations.
Acrylic Triblock Copolymer Design for Thermoreversible Gelcasting of Ceramics: Rheological and Green Body Properties
Authors: Seitz M. E. , Shull K. R. , Faber K. T.
Published: June 2009

Thermoreversible gelcasting (TRG) is an attractive net‐shape powder‐based processing technique which relies on the temperature‐driven gelation of a polymer solution. This study uses the TRG of alumina to investigate the implications of triblock copolymer design (block length, endblock fraction, and midblock chemistry) on rheological and green body properties. The liquid‐to‐solid transition and relaxation time in the gel state are controlled by the polymer's endblock length while the total polymer length controls the viscosity at high temperature. Although triblock design and concentration do not affect the green body porosity or sintered density, they do have significant effects on green body behavior. Triblocks with a high fraction of rubbery midblock behave as elastomers and confer significant toughness to the green bodies. In contrast, those with glassy midblocks increase the strength of the body but also behave in a brittle manner. Green body strength increases with increasing triblock concentration and is well described by a model for the strength of ceramic bodies with the binder localized at the particle necks.
Two‐Phase Coexistence in Single‐Grain BaTiO3–(Mn0.5Zn0.5)Fe2O4 Composites, Via Solid‐State Reaction
Authors: Yang Yaodong , Priya Shashank , Li Jie‐Fang , Viehland Dwight
Published: June 2009

We have developed a synthesis method of single‐grain two‐phase BaTiO3–(Mn0.5Zn0.5)Fe2O4 nanomaterials via a solid state reaction. The grains of BTO‐rich samples were found to have a rod‐like morphology with a high aspect ratio and a diameter of 200 nm, whereas the grains of MZF‐rich samples had a tetrahedral/octahedral cross‐section with a span of 200 nm. Such a synthesis of two‐phase perovskite/spinel single‐crystal grains with different grain geometries offers the potential to build new types of multiferroic materials.
A Huge Effect of Weak dc Electrical Fields on Grain Growth in Zirconia
Authors: Ghosh Santonu , Chokshi Atul H. , Lee Pilhwa , Raj Rishi
Published: June 2009

We show that the application of a modest dc electrical field, about 4 V/cm, can significantly reduce grain growth in yttria‐stabilized polycrystalline zirconia. These measurements were made by annealing samples, for 10 h at 1300°C, with and without an electrical field. The finding adds a new dimension to the role of applied electrical fields in sintering and superplasticity, phenomena that are critical to the net‐shape processing of ceramics. Grain‐growth retardation will considerably enhance the rates of sintering and superplasticity, leading to significant energy efficiencies in the processing of ceramics.
High‐Temperature Transmission Electron Microscopy and X‐Ray Powder Diffraction Studies of Polymorphic Phase Transitions in Ba4Nb2O9
Authors: Bezjak Jana , Rečnik Aleksander , Jančar Boštjan , Boullay Philippe , Evans Ivana Radosavljević , Suvorov Danilo
Published: June 2009

Polymorphic phase transitions in Ba4Nb2O9 were studied by thermal analyses, high‐temperature transmission electron microscopy and X‐ray powder diffractometry. Two stable polymorphs were isolated, low‐temperature α‐modification and high‐temperature γ‐modification, with the endothermic phase transition at 1176°C. The α→γ transformation is accompanied by the formation of a 120° domain structure, which is a consequence of hexagonal→orthorhombic unit cell reconstruction. Reheating the presintered γ‐Ba4Nb2O9 results in the formation of a metastable γ′‐modification (formerly known as β‐polymorph) in the temperature range between 360° and 585°C, before the γ→α transformation at 800°C. Above ∼490°C Ba4Nb2O9 becomes moderately sensitive to a loss of BaO. In air the surface of Ba4Nb2O9 grains decomposes to nanocrystalline Ba5Nb4O15 and BaO, which instantly reacts with atmospheric CO2 to form BaCO3. Surface reaction delays γ→α transformation up to 866°C in air. In vacuum the loss of BaO is even more enhanced and consequently the formation of minor Ba3Nb2O8 phase is observed above 1150°C.
Surface Chemical Characterization of Ceramic Materials: Adsorption and Degradation of 3,6,9‐Trioxadecanoic Acid on Nano‐ZrO2
Authors: Finke Thomas , Lingenfelser Dominic , Bindler Katharina , Eisele Ulrich , Bockhorn Henning , Brunklaus Gunther
Published: June 2009

This paper deals with the specific interaction of the dispersant 3,6,9‐trioxadecanoic acid (TODA) with nano‐ZrO2 surfaces. Special interest was directed towards degradation behavior of the adsorbates and its influence on dispersant capabilities of TODA regarding stabilization of ethanolic nano‐ZrO2 suspensions. ZrO2 adsorption sites and the adsorbates formed are examined by diffuse reflectance infrared Fourier transform spectroscopy, thermal analysis, 1H‐, and 13C‐cross polarization magic angle spinning solid‐state nuclear magnetic resonance spectroscopy. 1H as well as 13C‐chemical shifts and the configurations of the corresponding adsorbed TODA species on zirconia sites are predicted by means of density functional theory quantum chemical calculations for supporting the interpretation of the experimental spectral data obtained. This work shows that combination of analytical and theoretical methods is an effective approach characterizing surface chemical properties of ceramic materials, determining sorption properties of organic process additives, investigating correspondent elementary and degradation reactions as well as clarifying cause‐effect relationships in ceramic processes.