bluuebunny/crossref_metadata_2025 huggingface dataset:
Measuring Individual Differences in the Perfect Automation Schema
Authors: Merritt Stephanie M. , Unnerstall Jennifer L. , Lee Deborah , Huber Kelli
Published: April 2015

Objective

A self-report measure of the perfect automation schema (PAS) is developed and tested.

Background

Researchers have hypothesized that the extent to which users possess a PAS is associated with greater decreases in trust after users encounter automation errors. However, no measure of the PAS currently exists. We developed a self-report measure assessing two proposed PAS factors: high expectations and all-or-none thinking about automation performance.

Method

In two studies, participants responded to our PAS measure, interacted with imperfect automated aids, and reported trust.

Results

Each of the two PAS measure factors demonstrated fit to the hypothesized factor structure and convergent and discriminant validity when compared with propensity to trust machines and trust in a specific aid. However, the high expectations and all-or-none thinking scales showed low intercorrelations and differential relationships with outcomes, suggesting that they might best be considered two separate constructs rather than two subfactors of the PAS. All-or-none thinking had significant associations with decreases in trust following aid errors, whereas high expectations did not. Results therefore suggest that the all-or-none thinking scale may best represent the PAS construct.

Conclusion

Our PAS measure (specifically, the all-or-none thinking scale) significantly predicted the severe trust decreases thought to be associated with high PAS. Further, it demonstrated acceptable psychometric properties across two samples.

Application

This measure may be used in future work to assess levels of PAS in users of automated systems in either research or applied settings.
Ship-shape: Materializing leadership in the British Royal Navy
Authors: Hawkins Beverley
Published: April 2015

In this article, I contribute to posthumanist, actor-network influenced theories of leadership, drawing empirically on qualitative data collected at a Royal Navy shore establishment in Great Britain. I demonstrate how a fluid network of hybridized relationships between people and things affords shifting and multiple possibilities for making leadership matter. As configurations of actants evolve these affordances are altered, and the blackboxing processes hiding the material actants co-generating leadership effects are uncovered. A detailed explication of the politicized affordances within actor networks contributes to knowledge about how hybridized relationships co-enable possibilities for action that bring to life, reinforce and call into question the human-centred, gendered, colonialist web of assumptions and practices through which Royal Naval personnel understand and enact leadership.
Aramid nanofiber-reinforced transparent nanocomposites
Authors: Yang Ming , Cao Keqin , Yeom Bongjun , Thouless MD , Waas Anthony , Arruda Ellen M , Kotov Nicholas A
Published: April 2015

Nanoscale polymeric fibers are expected to bring about exceptional mechanical and optical properties in composite materials related to the better integration of different properties between fibers and polymers. The discovery of the first aramid nanofiber dispersion from commercial para-aramid macrofibers similar to Kevlar® developed by DuPont allowed the emergence of an innovative nanoscale building block with great potential for engineering novel high-performance polymer nanocomposites. Here we report the fabrication of aramid nanofiber-reinforced polyacrylic-acid thin films using vacuum-assisted flocculation. We show that the resulting composite has high transparency owing to the nanoscale size of the fibers. The multiple hydrogen bonds available at the interface between the polyacrylic acid and nanofibers result in significant improvement of mechanical properties, with Young's modulus outperforming single-walled carbon nanotube composites. The successful use of ANFs in producing transparent, strong and flexible polymer nanocomposites indicates their great potential as an effective reinforcing agent in optical applications.
Mesoscale modeling of S-2 glass/SC-15 epoxy composites: Plain-weave architecture
Authors: Carpenter Alexander J , Chocron Sidney , Anderson Charles E
Published: April 2015

S-2 glass composites can readily serve as backing materials for armor systems due to their light weight and tensile properties. However, high-fidelity ballistic modeling of these composites requires accurate predictions of their nonlinear deformation and failure behaviors, which can prove challenging. This paper describes simulations of a plain-weave S-2 glass composite at the mesoscale using a mesh geometry that individually models the S-2 glass yarns, epoxy resin matrix, and yarn/matrix interfaces as separate entities. Simulation results are compared to a wide variety of mechanical tests designed to measure the response of the composite to tension, shear, and delamination. Although the individual yarns, matrix, and interfaces are described using relatively simple material models, the overall composite model can accurately reproduce behaviors such as nonlinear deformation, yarn breakage, and delamination in both tension and shear.
Compression behavior of ultra-high modulus carbon/epoxy composites using ASTM D6641 and SACMA SRM 1R-94
Authors: Charles Glath Michael , Koudela Kevin , Strauch Eric
Published: April 2015

The compression modulus and compression strength of a proprietary ultra-high modulus carbon/epoxy composite are experimentally determined using SACMA SRM 1R-94 and ASTM D6641 for laminates with stacking sequences of [(0/ ± 60)s]2 and [(+60/0/−60)s]2. The moduli of both laminates are experimentally shown to be statistically equivalent; the strength of the [(0/ ± 60)s]2 laminate is shown to be significantly less than the [(+60/0/−60)s]2 laminate. A finite element model is developed for each compression test to predict the compression modulus and compression strength using the built-in damage progression algorithm in Abaqus. Premature end crushing is predicted in the modulus specimen of SACMA SRM 1R-94 for the [(+60/0/60)s]2 laminate. End crushing in the modeled SACMA SRM 1R-94 strength specimen is predicted to occur immediately after ultimate laminate failure for the [(+60/0/60)s]2 laminate. Fiber misalignment is found to significantly affect the predicted compression modulus and compression strength of the ultra-high modulus carbon/epoxy composite analyzed.
Improved mechanical properties of a water-activated polyurethane-glass fiber composite reinforced with amino-functionalized carbon nanofibers
Authors: Withers GJ , Souza JM , Yu Y , Cercone L , Khabashesku VN , Davis DC
Published: April 2015

The mechanical properties of a water-activated polyurethane–glass fiber composite reinforced using amino-functionalized carbon nanofibers are evaluated for ultimate tensile strength, Young’s modulus, ductility and fatigue life at 60℃. The amino-functionalized carbon nanofibers are dispersed in the water-activated polyurethane matrix at 0.4 weight percent (wt%) with respect to the glass fabric for comparison with the neat (or 0.0 wt% amino-functionalized carbon nanofibers) water-activated polyurethane–glass fiber composite material. Fatigue tests were performed at a stress-ratio (R-ratio) = +0.9. This cyclic loading level and temperature conditions would simulate a vibro-creep-fatigue type loading and response condition. The results showed that the water-activated polyurethane–glass fiber composite when reinforced with amino-functionalized carbon nanofibers (amino-functionalized carbon nanofibers water-activated polyurethane–glass fiber nanocomposite) had improved tensile strength, ductility and fatigue life properties in comparison to the neat composite, but there was a reduction in Young’s modulus in this nanocomposite material at high applied load levels. This amino-functionalized carbon nanofibers water-activated polyurethane–glass fiber nanocomposite could have worldwide applications for external surface repair or rehabilitation on existing civil-mechanical structures such as concrete or metal pilings, vessels and piping, to achieve an extended operational life under elevated temperatures and fatigue-type loading conditions.
Through a Cultural Lens
Authors: Atzaba-Poria Naama , Pike Alison
Published: April 2015

We set out to document how maternal and paternal negativity are related to children’s self-esteem during middle childhood in English and Indian families living in Britain. Although self-esteem is related to parental practices and parenting is a universal construct, the specifics of what may be associated with specific parenting practices varies across cultures. We hypothesized that due to distinct gender-based power structures, among the English families, maternal negativity would be related to lower child self-esteem, whereas among the Indian families, paternal negativity would be associated with lower child self-esteem. Children (aged 7-9.6) reported on their own self-esteem, whereas each parent reported on his or her parenting. We examined whether the correlations between parental negativity and children’s self-esteem were similar for, or specific to, English ( n = 59) and Indian ( n = 66) cultural groups, and whether parental negativity is related to children’s self-esteem in a similar way for mothers and fathers. British families living in West London participated in the study. For the Indian children, higher levels of paternal negativity were related to lower self-esteem, whereas, for the English children, higher levels of maternal negativity were related to lower self-esteem. Specificities in relationships (mother–child vs. father–child) and in cultural correlates are discussed.
Morphologic and Demographic Predictors of Third Molar Agenesis
Authors: Carter K. , Worthington S.
Published: April 2015

We aimed to consolidate all available data on worldwide third molar agenesis frequencies, with a particular emphasis on exploring the factors leading authors to find contradictory results for the demographic and morphologic predictors of this anomaly. A total of 12,376 studies were originally identified, then narrowed down to 1,312 for title/abstract screening. On the basis of our inclusion and exclusion criteria, we selected 92 studies, containing 100 effect sizes and 63,314 subjects, for systematic review and metaregression. The worldwide rate of agenesis was found to be 22.63% (95% confidence interval = 20.64% to 24.76%), although the estimates ranged from 5.32% to 56.0%. Our subgroup analyses revealed that women are 14% more likely than men to have agenesis of ≥1 third molars and that maxillary agenesis was 36% more likely than mandibular agenesis in both sexes. Furthermore, we found that having agenesis of 1 or 2 molars was most common, while agenesis of 3 or 4 molars was least common. Finally, we found large differences among agenesis frequency depending on geographic region. This information is expected to be of use not only to clinicians and patients but also to policy makers, given the implications for third molar extraction protocols.
Flagellin-PAc Fusion Protein Inhibits Progression of Established Caries
Authors: Bao R. , Yang J.Y. , Sun Y. , Zhou D.H. , Yang Y. , Li Y.M. , Cao Y. , Xiao Y. , Li W. , Yu J. , Zhao B.L. , Zhong M.H. , Yan H.M.
Published: April 2015

Dental caries remains one of the most common infectious diseases of humankind, which develops slowly throughout life, affecting children, adolescents, and adults. A vaccine against caries is urgently needed. We previously developed recombinant flagellin as a mucosal adjuvant for anti– Streptococcus mutans vaccines by nasal immunization. Furthermore, we demonstrated a fusion protein strategy that combined flagellin and the target surface adhesion protein (PAc) in a single construct. This construct enhanced specific IgA responses in oral fluids and provided improved prophylactic protection against caries. In the present study, we observed prolonged progression of dental caries in rats after S. mutans Ingbritt challenge. In addition, we observed a therapeutic effect of the flagellin-PAc fusion protein (KF-rPAc) against dental caries as a mucosal vaccine with a new immunization protocol. The present study demonstrated that KF-rPAc by nasal immunization can promote PAc-specific systemic and mucosal antibody responses and inhibit dental caries progression efficiently after the implant of S. mutans into the oral cavity of the rats. The rats immunized with KF-rPAc exhibited 53.9% caries reduction compared with the sham-immunized rats. Our data support the concept of administration of KF-rPAc to humans after infection and even caries that has begun to alleviate caries progression. In conclusion, our study demonstrated that KF-rPAc could be used as an anticaries therapeutic mucosal vaccine.
Parental Awareness of Substance Use Among Adolescents in a Junior High School Sample
Authors: Berge Jonas , Sundell Knut , Öjehagen Agneta , Höglund Peter , Håkansson Anders
Published: April 2015

There is a lack of studies assessing parental awareness of adolescent alcohol, cigarette, and drug use in the general adolescent population. A total of 1,426 adolescents aged 14 to 16, and their parents, answered questions about adolescent substance use annually during junior high school. Sensitivity for parental report of adolescent substance use was low: 5.6% to 26% for drunkenness, 14.3% to 20.6% for cigarettes, and 4.9% to 12% for illicit drugs. Higher age and higher frequency of use were positively associated with parental awareness of drunkenness and cigarette use. Female sex was associated with higher parental awareness of drunkenness. Higher school performance was negatively associated with parental awareness of drunkenness in Grade 9 and with cigarette use in Grades 8 to 9. Parental awareness of adolescent drunkenness, and cigarette and illicit drug use in the general population is low. Factors of importance for parental awareness are identified.
Quality of diagnosis and monitoring of tuberculosis in Northern Ethiopia: medical records-based retrospective study
Authors: Mala George , Spigt Mark G , Gidding Luc G , Blanco Roman , Dinant Geert-Jan
Published: April 2015

Objectives

To determine quality of diagnosis and monitoring of treatment response of patients with smear-negative pulmonary tuberculosis (TB) compared with smear-positive cases in Ethiopia.

Methods

A retrospective analysis of medical records of newly diagnosed pulmonary TB cases that were registered for taking anti-TB medication and had completed treatment between 2010 and 2012. We evaluated the percentage of cases that were managed according to the International Standards of Tuberculosis Care (ISTC) and compared smear-negative with smear-positive cases.

Results

We analysed 1168 cases of which 742 (64%) were sputum smear-negative cases. Chest radiography examination at diagnosis and microbiological testing at the end of the intensive phase of treatment was performed in a smaller proportion than in smear-positive TB cases (70% vs. 79%, P value <0.001) and (70% vs. 95%, P value <0.001), respectively.

Conclusions

Clinical actions recommended in the ISTC are of greatest importance in minimising pitfalls in care of smear-negative TB yet were performed less often in smear-negative than smear-positive TB cases.
Ecometrics in the Age of Big Data
Authors: O’Brien Daniel Tumminelli , Sampson Robert J. , Winship Christopher
Published: April 2015

The collection of large-scale administrative records in electronic form by many cities provides a new opportunity for the measurement and longitudinal tracking of neighborhood characteristics, but one that will require novel methodologies that convert such data into research-relevant measures. The authors illustrate these challenges by developing measures of “broken windows” from Boston’s constituent relationship management (CRM) system (aka 311 hotline). A 16-month archive of the CRM database contains more than 300,000 address-based requests for city services, many of which reference physical incivilities (e.g., graffiti removal). The authors carry out three ecometric analyses, each building on the previous one. Analysis 1 examines the content of the measure, identifying 28 items that constitute two independent constructs, private neglect and public denigration. Analysis 2 assesses the validity of the measure by using investigator-initiated neighborhood audits to examine the “civic response rate” across neighborhoods. Indicators of civic response were then extracted from the CRM database so that measurement adjustments could be automated. These adjustments were calibrated against measures of litter from the objective audits. Analysis 3 examines the reliability of the composite measure of physical disorder at different spatiotemporal windows, finding that census tracts can be measured at two-month intervals and census block groups at six-month intervals. The final measures are highly detailed, can be tracked longitudinally, and are virtually costless. This framework thus provides an example of how new forms of large-scale administrative data can yield ecometric measurement for urban science while illustrating the methodological challenges that must be addressed.
Practitioner Envy and Construction of the Other in Public Administration
Authors: Nisar Muhammad A.
Published: April 2015

This article focuses on the personal dimension of the identity crisis in public administration and its impact on academic research. Devoid of a socially recognizable secure academic identity, practitioner represents the closest to an authentic identity for the public administration researcher. This identification with the practitioner comes at a price and leads to the treatment of “public” as the Other in public administration research. Drawing insights from Said’s treatment of the concept of the Other, various dimensions of the discourses of power and knowledge in public administration which lead to categorization of the public as the Other are discussed.
Civic Engagement and Citizenship Development: The Case of Homeowners’ Participation in Neighborhood Affairs in Beijing
Authors: Wang Weijie , Li Hui , Cooper Terry L.
Published: April 2015

This article investigates the behavioral consequences of homeowners’ participation in neighborhood affairs in Beijing, China. The research is based on semistructured interviews with homeowner leaders, property managers, and government officials. Participation fosters ethical citizenship by helping homeowners to acquire democratic skills, increase their awareness of property and political rights, and cultivate a sense of community. The development of ethical citizenship motivates homeowners to redefine legal citizenship. Homeowners have begun to take their rights seriously and actively participate in grassroots elections. The interaction between ethical and legal citizenship may carry important implications for future political development in China.
The Importance of Ethical Environment to Organizational Performance in Employment at Will States
Authors: Hijal-Moghrabi Imane , Sabharwal Meghna , Berman Evan M.
Published: April 2015

This article highlights the importance of ethical environment in enhancing organizational performance. It is vital that organizations set ethical standards for their employees alongside providing an environment that fosters trust and commitment, provides leadership, and creates a high quality of workforce to improve organizational performance. To study the impact of ethical environment on organizational performance, we employ elements from André de Waal’s high-performance organization (HPO) framework. Data for this study come from a national survey conducted in four states in the United States, which are classified as at-will employment states: Oregon, Utah, Washington, and Florida. We find evidence that ethical environment plays an important role in determining organizational performance. This is particularly important in the context of at-will employment, where state governments are facing the challenge to maintain employee commitment while improving organizational performance.
Teduglutide for Safe Reduction of Parenteral Nutrient and/or Fluid Requirements in Adults
Authors: Naberhuis Jane K. , Tappenden Kelly A.
Published: April 2015

Background: Teduglutide (Gattex; NPS Pharma, Bedminster, NJ), a recombinant analogue of human glucagon‐like peptide 2 (GLP‐2), is the first long‐term medical therapy approved for the treatment of adults dependent on parenteral nutrition (PN). Objective: To assess the efficacy and safety of teduglutide in reducing PN (parenteral nutrient and/or fluid) requirements in PN‐dependent adults. Methods: Studies were identified using predefined search criteria and multiple databases, including Medline and Embase. The search was completed to November 30, 2014, in the absence of date or study design restrictions. Citation inclusion criteria and methodological quality were assessed by 2 independent reviewers. Outcomes of interest were changes in parenteral nutrient or fluid requirements and adverse event incidence. From 2693 unique citations, 76 abstracts were reviewed. Fourteen reports met the inclusion criteria, including data from 2 phase III, double‐blind, placebo‐controlled clinical trials and their respective extension studies. Data extraction was performed by 2 reviewers using a standardized form. Results: Teduglutide reduced PN requirements compared with placebo, whereas adverse event incidence was similar. Limitations: Number of subjects studied and length of follow‐up. Conclusions: Teduglutide appears to be a safe and well‐tolerated means to reduce PN dependence in adults, regardless of PN dependence duration.
Destructive Leadership Behaviors and Workplace Attitudes in Schools
Authors: Woestman Daniel S. , Wasonga Teresa Akinyi
Published: April 2015

The study investigated destructive leadership behaviors (DLBs) and their influence on K-12 workplace attitudes (subordinate consideration for leaving their job, job satisfaction, and levels of stress). Quantitative survey method was used to gather data from experienced professional educators. Analyses of data show that the practice of DLB exists across all school leadership levels. Subordinate-directed behavior had the highest incidence of DLB, and principals and females experienced higher levels of DLB. DLB had negative correlation with job satisfaction, job stress, and consideration for leaving. Despite high levels of job satisfaction, respondents experienced feelings of stress and consideration for leaving their job.
A multilevel regression of patient-reported outcome measures after varicose vein treatment in England
Authors: El-Sheikha Joseph
Published: April 2015

Introduction

The relationship between patient and hospital characteristics and their influence on quality of life (QoL) variance following varicose vein treatment is little understood. Whilst Patient-reported outcome measures (PROMs) can record postoperative outcomes, the actual comparison of PROMs between hospitals can be misleading when the clustered nature of varicose vein care is overlooked. Multilevel models can accommodate hierarchical data and therefore can provide a more accurate reflection of the relationship between patients and hospitals when investigating postoperative outcomes.

Methods

A multilevel model of PROMs was developed to analyse the relationship of patient characteristics (gender, age), postoperative outcomes (complications, postoperative satisfaction, treatment success) and hospital type (operative volume and if private or NHS institution) with the change in Aberdeen Varicose Vein Score (AVVQ) six months after varicose vein treatment.

Results

Between April 2010 and July 2014, some 24,460 PROMs from 162 hospitals were analysed. Whilst the majority of variance in AVVQ improvement was due to patient factors, a small but statistically significant amount of variance was detected due to differences between hospitals. Multilevel regression revealed that females saw a greater improvement in AVVQ, as did those who reported greater levels of treatment success and satisfaction. Patient age, complications, intervention, readmission, hospital size and hospital type were not significantly associated with AVVQ improvement.

Conclusion

Although QoL is intrinsically tied to an individual, hospitals can provide a small but potentially important benefit in AVVQ improvement following vein treatment. A patient-centred approach is therefore recommended to optimise patient outcomes.
Does hospital need more hospice beds? Hospital charges and length of stays by lung cancer inpatients at their end of life: A retrospective cohort design of 2002–2012
Authors: Kim Sun Jung , Han Kyu-Tae , Kim Tae Hyun , Park Eun-Cheol
Published: April 2015

Background:

Previous studies found that hospice and palliative care reduces healthcare costs for end-of-life cancer patients.

Aim:

To investigate hospital inpatient charges and length-of-stay differences by availability of hospice care beds within hospitals using nationwide data from end-of-life inpatients with lung cancer.

Design:

A retrospective cohort study was performed using nationwide lung cancer health insurance claims from 2002 to 2012 in Korea.

Setting and participants:

Descriptive and multi-level (patient-level and hospital-level) mixed models were used to compare inpatient charges and lengths of stay. Using 673,122 inpatient health insurance claims, we obtained aggregated hospital inpatient charges and lengths of stay from a total of 114,828 inpatients and 866 hospital records.

Results:

Hospital inpatient charges and length of stay drastically increased as patients approached death; a significant portion of hospital inpatient charges and lengths of stay occurred during the end-of-life period. According to our multi-level analysis, hospitals with hospice care beds tend to have significantly lower end-of-life hospital inpatient charges; however, length of stay did not differ. Hospitals with more hospice care beds were associated with reduction in hospital inpatient charges within 3 months before death.

Conclusion:

Higher end-of-life healthcare hospital charges were found for lung cancer inpatients who were admitted to hospitals without hospice care beds. This study suggests that health policy-makers and the National Health Insurance program need to consider expanding the use of hospice care beds within hospitals and hospice care facilities for end-of-life patients with lung cancer in South Korea, where very limited numbers of resources are currently available.
Euthanasia and physician-assisted suicide in dementia: A qualitative study of the views of former dementia carers
Authors: Tomlinson Emily , Spector Aimee , Nurock Shirley , Stott Joshua
Published: April 2015

Background:

Despite media and academic interest on assisted dying in dementia, little is known of the views of those directly affected.

Aim:

This study explored the views of former carers on assisted dying in dementia.

Design:

This was a qualitative study using thematic analysis.

Setting/participants:

A total of 16 former carers of people with dementia were recruited through national dementia charities and participated in semi-structured interviews.

Results:

While many supported the individual’s right to die, the complexity of assisted dying in dementia was emphasized. Existential, physical, psychological and psychosocial aspects of suffering were identified as potential reasons to desire an assisted death. Most believed it would help to talk with a trained health professional if contemplating an assisted death.

Conclusion:

Health workers should be mindful of the holistic experience of dementia at the end of life. The psychological and existential aspects of suffering should be addressed, as well as relief of physical pain. Further research is required.
Acute symptomatic complications among patients with advanced cancer admitted to acute palliative care units: A prospective observational study
Authors: Hui David , dos Santos Renata , Reddy Suresh , de Angelis Nascimento Maria Salete , Zhukovsky Donna S , Paiva Carlos Eduardo , Dalal Shalini , Costa Everaldo Donizeti , Walker Paul , Scapulatempo Heloisa Helena , Dev Rony , Crovador Camila Souza , De La Cruz Maxine , Bruera Eduardo
Published: April 2015

Background:

Limited information is available on the symptomatic complications that occur in the last days of life.

Aim:

We documented the frequency, clinical course, and survival for 25 symptomatic complications among patients admitted to acute palliative care units.

Design:

Prospective longitudinal observational study.

Measurements:

Their attending physician completed a daily structured assessment of symptomatic complications from admission to discharge or death.

Setting/participants:

We enrolled consecutive advanced cancer patients admitted to acute palliative care units at MD Anderson Cancer Center, USA, and Barretos Cancer Hospital, Brazil.

Results:

A total of 352 patients were enrolled (MD Anderson Cancer Center = 151, Barretos Cancer Hospital = 201). Delirium, pneumonia, and bowel obstruction were the most common complications, occurring in 43%, 20%, and 16% of patients on admission, and 70%, 46%, and 35% during the entire acute palliative care unit stay, respectively. Symptomatic improvement for delirium (36/246, 15%), pneumonia (52/161, 32%), and bowel obstruction (41/124, 33%) was low. Survival analysis revealed that delirium ( p < 0.001), pneumonia ( p = 0.003), peritonitis ( p = 0.03), metabolic acidosis ( p < 0.001), and upper gastrointestinal bleed ( p = 0.03) were associated with worse survival. Greater number of symptomatic complications on admission was also associated with poorer survival ( p < 0.001).

Conclusion:

Symptomatic complications were common in cancer patients admitted to acute palliative care units, often do not resolve completely, and were associated with a poor prognosis despite active medical management.
Cartilaginous Tumors of the Larynx and Trachea in the Dog
Authors: Ramírez G. A. , Altimira J. , Vilafranca M.
Published: April 2015

Cartilaginous tumors of the larynx and trachea are uncommon in the dog. The authors describe 10 cases diagnosed between 1995 and 2014 and review 16 cases in the literature. Seven of our cases were tracheal and 3 were laryngeal. Two of the laryngeal tumors were chondromas, which have not been previously reported in this site. The third laryngeal tumor was a myxochondroma. Of the 7 tracheal tumors, 6 arose from the ventral tracheal wall, including 2 that were extraluminal. Tracheal tumor types included chondrosarcoma ( n = 3), chondroma ( n = 2), and osteochondroma ( n = 2). All of the laryngeal tumors and 5 of 7 of the tracheal tumors occurred in adult dogs (aged 5–11 years). The 2 tracheal osteochondromas were in young dogs (3–4 months) and were intrathoracic, while the remaining tracheal tumors were cervical. Surgical excision had a good outcome in most cases. Combining our 10 cases with the 16 previously reported cases showed that 6 (27%) of the affected dogs were Arctic breeds (Alaskan Malamute or Siberian Husky) suggesting a predisposition in this type of dog.
Ontological turns, turnoffs and roundabouts
Authors: Sismondo Sergio
Published: April 2015

There has been much talk of an ‘ontological turn’ in Science and Technology Studies. This commentary explores some recent work on multiple and historical ontologies, especially articles published in this journal, against a background of constructivism. It can be tempting to read an ontological turn as based and promoting a version of perspectivism, but that is inadequate to the scholarly work and opens multiple ontologies to serious criticisms. Instead, we should read our ontological turn or turns as being about multiplicities of practices and the ways in which these practices shape the material world. Ontologies arise out of practices through which people engage with things; the practices are fundamental and the ontologies derivative. The purchase in this move comes from the elucidating power of the verbs that scholars use to analyze relations of practices and objects – which turn out to be specific cases of constructivist verbs. The difference between this ontological turn and constructivist work in Science and Technology Studies appears to be a matter of emphases found useful for different purposes.
Performance of at-risk students in dynamics following a statics class with additional recitation time
Authors: Burkhardt John
Published: April 2015

Comparisons are made between the final exam and final course grades of at-risk students in dynamics who took one of two versions of the same statics course. A standard version of the statics course met 3 hours per week over the course of a 15-week semester, while a second version met 4 hours per week. During the 11-year timeframe covered by this study, the 4-hour statics course was populated by students identified as ‘at risk’ using an informal screening procedure. For comparison with this group, using the same enrollment data, a second group of at-risk students was identified from the 3-hour statics class using a more formal screening procedure, based on logistic regression. A performance comparison of the two groups shows that the extra contact hour had a minor, statistically insignificant effect on student final exam and final course grades in dynamics. As a result of this study and a related study examining the effect of additional class time on statics performance, the 4-hour statics class is no longer offered.
Feasibility modeling of a truss-braced wing as a beam
Authors: Dym Clive L , Williams Harry E
Published: April 2015

This article presents a case study on the use of elementary beam and truss theory to ascertain whether a truss-braced wing is structurally feasible. It begins with a brief history of airplane structures, and then explains how elementary structures theory can be used to explore one aspect of how airplanes work. Its purpose is solely to see whether a truss-braced wing is structurally sensible, as a prelude to performing full-scale analyses of such configurations that would include their aerodyamics, materials, controls and economics.
Returning to driving after stroke: A systematic review of adherence to guidelines and legislation
Authors: Frith Janet , Hubbard Isobel J , James Carole L , Warren-Forward Helen
Published: April 2015

Introduction

This systematic review aimed to determine whether stroke survivors routinely received return-to-driving education in the acute hospital setting prior to discharge home; and if education was provided, were the restrictions in driving guidelines adhered to.

Method

A systematic search was conducted of PubMed, Medline, Embase, Cumulative Index to Nursing and Allied Health Literature (CINAHL), PsychINFO, Web of Science, Scopus, Pedro and OTseeker databases for original research reporting findings on the adherence to return-to-driving legislation and clinical guidelines after stroke, and return-to-driving behaviours in stroke survivors up to 1 month post stroke.

Results

Three studies met the inclusion criteria and reported on a combined total of 252 stroke survivors living in the United Kingdom. Forty-eight per cent of stroke survivors received education on the 1 month driving restriction. A total of 61.4% of participants waited 1 month prior to returning to driving.

Conclusion

This review found that there is limited literature available on the management of return to driving following acute stroke but there is evidence that education may not be routinely provided in the acute hospital setting and that many stroke survivors could be returning to driving within the 1 month restriction.
To scheme or bid? Choice of takeover method and impact on premium
Authors: Bugeja Martin , da Silva Rosa Raymond , Izan HY , Ngan Susan
Published: April 2015

In recent years there has been an increasing use of members’ schemes of arrangement to bring about a change in corporate control. This increasing use of schemes has been criticised in public quarters on the basis that unlike takeovers, schemes are not subject to the Eggleston principles and have arguably led to target shareholders receiving lower offer prices. This study provides the first large-sample empirical evidence on differences between schemes and takeovers. We find that the likelihood of the use of schemes significantly increases when target firm ownership concentration is higher and when the bidder has a lower toehold. Scheme usage is also more likely for larger targets and bidders with higher leverage. Consistent with public criticisms of schemes, we find that after controlling for self-selection premiums in schemes are significantly lower than those in takeovers.
Law and Intergenerational Relationships
Authors: Doron Israel , Lowenstein Ariela , Biggs Simon
Published: April 2015

Background: In any aging society, the sociolegal construction of intergenerational relationships is of great importance. This study conducts an international comparison of a specific judicial issue: whether active labor unions have the legal right to strike for the purpose of improving the benefits given to nonactive workers (specifically, pensioners). Method: A comparative case law methodology was used. The texts of three different Supreme Court cases—in the United States, Canada, and Israel—were analyzed and compared. Findings: Despite the different legal outcomes, all three court rulings reflect a disregard of known and relevant social gerontology theories of intergenerational relationships. Conclusion: Social gerontological theories can play an important role in both understanding and shaping judicial policies and assisting the courts in choosing their sociojudicial narratives.
Redesigning Personnel Preparation
Authors: Little Mary E. , Sobel Donna , McCray Erica D. , Wang Jun
Published: April 2015

Changing legal requirements, economic demands, accountability, and student demographics focus the need for reform among personnel preparation programs. Although redesign efforts in general and special education teacher preparation programs have increased, little evidence from research describes enhancement initiatives. In this article, the authors report the findings of an investigation of contextual variables related to reforming teacher preparation as reported by project personnel at Institutions of Higher Education (IHEs) who were awarded 325T priority grants by the Office of Special Education Programs (OSEP) during a 5-year period. This study employed a sequential mixed-methods design, which included (a) the administration of a survey to all project directors and (b) interviews with a purposive sample of project directors. From the analysis, results and future implications are included.
Contextualizing Work: The Influence of Workplace History and Perceptions of the Future on Lean Production at Three GM Plants
Authors: Rothstein Jeffrey S.
Published: April 2015

Research recognizes both a tension between standardized work and employee participation as well as the fact that management and labor negotiate both formally and informally over the reorganization of work. Through a comparison of the lean production systems being implemented at three General Motors assembly plants, this article demonstrates the tension between standardization and participation to be socially constructed due, in part, to workplace historical context. Workplace history shapes the attitudes of actors as they negotiate change and can become a significant obstacle to implementing teamwork and employee participation schemes, while perceptions of the future may determine whether or not those obstacles are overcome.
Comparison between novel waverider generated from flow past a pointed von Karman ogive and conventional cone-derived waverider
Authors: Ding Feng , Shen Chi-bing , Liu Jun , Huang Wei
Published: April 2015

This study conducts a comparison between a novel waverider generated from axisymmetric supersonic flow past a pointed von Karman ogive and a conventional cone-derived waverider generated from the axisymmetric supersonic flow past a cone. First, a pointed von Karman ogive is obtained by sharpening the blunt nose of the original von Karman ogive to a point. Then, a cone with the same shock wave radius at the base plane as that of the pointed von Karman ogive when it travels at a designated supersonic speed is designed. Both axisymmetric supersonic flows past the pointed von Karman ogive and the cone are calculated using the method of characteristics, and the two calculated flow fields are employed as the new and conventional basic flow fields of the waveriders, respectively. Second, a novel waverider is generated from the new basic flow field past the pointed von Karman ogive, using the streamline tracing technique, and a conventional cone-derived waverider is generated from the conventional basic flow field past the cone, using the streamline tracing technique. Finally, numerical methods are employed to verify the design procedures of the novel and conventional cone-derived waveriders, and to analyze the differences between both types of waverider. The obtained results show that the novel waverider possesses lower drag and higher lift-to-drag ratios, while the conventional cone-derived waverider has a higher internal volume and volumetric efficiency.
Improving slip factor prediction for centrifugal pumps using artificial neural networks
Authors: Ghaderi Mohsen , Najafi Amir F , Nourbakhsh Ahmad
Published: April 2015

Slip factor is an important parameter in the performance prediction of centrifugal pumps. This paper presents a new approach improving slip factor estimation of centrifugal pumps. In order to understand the effects of geometrical parameters of impeller (i.e. blade number, blade outlet angle, radius ratio, and blade turning rate) on slip factor, a set of computational fluid dynamics based analyses were carried out for over 70 different impellers by means of a commercial code, CFX. The numerical model was validated with the available experimental data. Subsequently, a multilayer feed-forward neural network, as a popular neural network based fitting tool, was used to generate a mapping between blade geometrical parameters as input variables and slip factor as output variable. The ANN (i.e. artificial neural network) model generalization capability was assessed by comparing the network predictions with those calculated from the test data. The comparative assessment of different slip models showed that the neural network model has succeeded in improving the accuracy of previous slip factor models for centrifugal pumps.
Flow measurement and simulation of a radial inlet for centrifugal compressor
Authors: Han Fenghui , Mao Yijun , Tan Jiajian , Zhao Cun , Zhang Yiyun
Published: April 2015

This paper presents an experimental and numerical research on the internal flow of a typical radial inlet for centrifugal compressor. Detailed flow measurements were carried out with five-hole probes, consisting of 106 sampling holes and 2178 measuring points. Automatic calibrating and measuring systems, which made the probe calibrations, measurements and data acquisitions controlled by computer, were developed and used to accelerate the flow measurements. Since separations and vortices in the radial inlet were not able to be accurately measured by five-hole probes, numerical simulation was adopted to assist in the flow analysis of the radial inlet in the present study. The investigation indicated that there were five main flow separations and vortices in the present radial inlet. Four of them were generated in the plenum, making the plenum the primary cause of the flow loss and the major factor of the flow distortions in the radial inlet. The last flow separation was generated on the inlet side of the flange at the 90° turning and extended to the exit of the axial duct. Besides, the symmetrical tangential flows in the radial inlet made positive and negative yaw angles with absolute value up to over 15° distributed in the tangential direction of the radial inlet’s exit, which will probably increase the incidence loss in the blade passages and negatively affect the work capability of the impeller. Based on the flow analysis and discussions, preliminary suggestions are proposed to provide references for the improvements of radial inlet.
A multi-proxy peat study of Holocene vegetation history, bog development, and carbon accumulation on northern Vancouver Island, Pacific coast of Canada
Authors: Lacourse Terri , Davies Marissa A
Published: April 2015

We present a multi-proxy paleoenvironmental study on a 10,400 cal. yr peat sequence from an ombrotrophic bog in coastal British Columbia, Canada. Pollen, non-pollen palynomorph, plant macrofossil, and physicochemical analyses (bulk density, %C, %N, δ13C, and δ15N isotopes) were used to document changes in vegetation, bog development, and carbon and nitrogen accumulation. Pollen assemblages indicate that regional vegetation in the warm, relatively dry early Holocene was mixed coniferous forest with scattered Pseudotsuga menziesii. Herbaceous peat with a C:N of ~28, combined with Nuphar microfossils and relatively high %N, suggests the presence of a herb-dominated peatland with standing water and/or bog pools. Carbon and nitrogen accumulation were at their highest during this early Holocene period at mean rates of 30.6 and 1.2 g/m2/cal. yr, respectively. By 8000 cal. yr BP and under a cooler, wetter climate, northern Vancouver Island supported Tsuga heterophylla rainforest similar to today. Decreasing relative water table, inferred from testate amoebae and fungal remains, facilitated the establishment of a Sphagnum bog by 8000 cal. yr BP with abundant ericaceous shrubs after 5000 cal. yr BP. Temporal variation in carbon accumulation rates corresponds with changes in plant functional types and hydrological conditions: rates were lowest in the early to mid-Holocene during accumulation of Sphagnum peat (7.1 g/m2/cal. yr) and increased in late Holocene ligneous peat (12.4 g/m2/cal. yr). Our multi-proxy approach not only demonstrates the overarching control of climate on bog development and carbon and nitrogen accumulation, with seasonality likely playing a major role, but also highlights the strong influence of autogenic processes at a local scale.
The seasonal water temperature cycle in the Arctic Dicksonfjord (Svalbard) during the Holocene Climate Optimum derived from subfossil Arctica islandica shells
Authors: Beierlein Lars , Salvigsen Otto , Schöne Bernd R , Mackensen Andreas , Brey Thomas
Published: April 2015

Future climate change will have significant effects on ecosystems worldwide and on polar regions in particular. Hence, palaeo-environmental studies focussing on the last warmer-than-today phase (i.e. the early Holocene) in higher latitudes are of particular importance to understand climate development and its potential impact in polar systems. Molluscan bivalve shells constitute suitable bio-archives for high-resolution palaeo-environmental reconstructions. Here, we present a first reconstruction of early Holocene seasonal water temperature cycle in an Arctic fjord based on stable oxygen isotope (δ18Oshell) profiles in shells of Arctica islandica (Bivalvia) from raised beach deposits in Dicksonfjorden, Svalbard, dated at 9954–9782 cal. yr BP. Reconstructed maximum and minimum bottom water temperatures for the assumed shell growth period between April and August of 15.2°C and 2.8°C imply a seasonality of about 12.4°C for the early Holocene. In comparison to modern temperatures, this indicates that average temperature declined by 6°C and seasonality narrowed by 50%. This first palaeo-environmental description of a fjord setting during the Holocene Climate Optimum at Spitsbergen exceeds most previous global estimates (+1–3°C) but confirms studies indicating an amplified effect (+4–6°C) at high northern latitudes.