bluuebunny/crossref_metadata_2025 huggingface dataset:
Small Group Computer-Assisted Instruction With SMART Board Technology
Authors: Campbell Monica L. , Mechling Linda C.
Published: July 2008

This investigation examined the effectiveness of teaching letter sounds in a small group arrangement using computer-assisted instruction with SMART Board technology and a 3s constant time delay procedure to three students with learning disabilities. A multiple probe design across letter sound sets and replicated across students evaluate the effectiveness of the program and students' acquisition of other students' letter sounds through observational learning. In addition, students were assessed on their acquisition of incidental information presented in the instructive feedback statements following correct responses to target and nontarget stimuli. Results indicate that (a) the program was effective in teaching letter sounds to three students and (b) students acquired some letter sounds targeted for other students and incidental information (letter names) presented in the instructive feedback statements for their own and other group members' target stimuli. Findings are discussed in terms of presenting small group instruction through interactive white board technology.
Home Literacy Environments of Young Children With Down Syndrome
Authors: Al Otaiba Stephanie , Lewis Sandra , Whalon Kelly , Dyrlund Allison , McKenzie Amy R.
Published: July 2008

Early home literacy experiences, including parent—child book reading, account for a significant amount of children's later reading achievement. Yet there is a very limited research base about the home literacy environments and experiences of children with cognitive disabilities. The purpose of this study is to describe findings from a Web-based survey of home literacy environments of young children with Down syndrome. Respondents ( n = 107) were mostly mothers; a majority were well educated. Findings suggest that respondents gave literacy a higher priority than reported in prior research on children with disabilities. More than 70% of respondents had 50 or more children's books and also had literacy materials including flash cards, magnetic letters, and educational videos or computer games. Most parents read to their children and used these literacy materials 10 to 30 min per day. Respondents reported that their children had reached many important early literacy milestones, and they also described having relatively ambitious lifelong literacy goals for their children. Important implications for research and practice are discussed.
Cultivating Caring Relationships Between Teachers and Secondary Students With Emotional and Behavioral Disorders
Authors: Mihalas Stephanie , Morse William C. , Allsopp David H. , Alvarez McHatton Patricia
Published: July 2008

Educating secondary students with emotional and behavioral disorders (EBD) is often an overwhelming task that places high demands on teachers. Existing research on effective social-emotional/behavioral and academic interventions for students with EBD is limited but expanding. Unfortunately, school and life outcomes for these students are dismal compared to other students. Certainly, there is much to learn about achieving positive outcomes for students with EBD. This article examines the potential role that caring teacher—student relationships have in achieving better outcomes for students with EBD within their current educational contexts. A rationale for why developing caring teacher—student relationships is important to improved outcomes for students with EBD is presented based on the current literature on caring teacher—student relationships. Potential barriers are delineated, followed by a summary of practices that serve as starting points for developing caring relationships between teachers and students with EBD. Last, research implications are suggested.
Risk Factors for Child and Adolescent Maltreatment
Authors: Mersky Joshua P. , Berger Lawrence M. , Reynolds Arthur J. , Gromoske Andrea N.
Published: July 2008

This study investigates associations between individual, family, and extrafamilial factors and the likelihood of subsequent childhood and adolescent maltreatment. The authors analyzed 1,411 participants in the Chicago Longitudinal Study whose maltreatment records were verified from administrative data. Findings suggest that maternal age at the child's birth was a robust predictor of maltreatment outcomes. Receipt of public assistance and single-parent family status were significantly associated with select outcomes. Among school-age indicators examined, parent participation in school was negatively associated with most maltreatment outcomes. Participation in the Chicago Child-Parent Center program was negatively associated with maltreatment, although effects varied by type and timing of maltreatment. In separate analyses, several factors were associated with neglect, but only maternal age at the child's birth was associated with physical abuse. Findings suggest that prevention programs may need to target select populations and specific mechanisms associated with different types of maltreatment to maximize effectiveness.
The Wender Utah Rating Scale
Authors: Hill B.D. , Pella Russell D. , Singh Ashvind N. , Jones Glenn N. , Gouvier Wm. Drew
Published: July 2008

Objective: The Wender Utah Rating Scale (WURS) is used to retroactively assess ADHD symptoms. This study sought to determine whether the WURS actually functions as an index of dysfunctional personality traits. Method: Five hundred twenty-two adult participants completed the WURS and at least one of the following measures: Wechsler Adult Intelligence Scale—III (WAIS-III), Trails Making Test (Forms A and B), Conners' Continuous Performance Test, d2 Test of Attention, and the Personality Assessment Inventory (PAI). Results: The WURS correlated significantly with all PAI clinical and treatment scales; however, of the neuropsychological measures, only the CPT significantly correlated with the WURS score. Multiple regression analyses revealed a significant model that included clinical and treatment scales from the PAI as well as working memory and processing speed indexes from the WAIS-III that accounted for 39% of the variance in WURS scores. Conclusion: Performance on the WURS was more related to dysfunctional personality traits than to actual attentional performance in this young adult sample. (J. of Att. Dis. 2009; 13(1) 87-94)
Sport Participation and Anxiety in Children with ADHD
Authors: Kiluk Brian D. , Weden Sarah , Culotta Vincent P.
Published: July 2008

Objective: Few studies have examined the psychological benefits of physical activity in children with ADHD who may be at higher risk for mood and anxiety problems. This study explores the relationship between participation in physical activity and emotional functioning in children with ADHD. Method: Scores on parent-reported measures of mood and behavior were retrospectively compared among a group of 65 children (ages 6 to 14) diagnosed with ADHD based on their amount of sport participation. A total of 32 children diagnosed with a learning disorder (LD) were used as a comparison group. Results: Children with ADHD who participated in three or more sports displayed significantly fewer anxiety or depression symptoms than did those who participated in fewer than three sports. These differences were not evident among children with LDs. Conclusion: Results suggest that active sport participation may be associated with a reduced expression of anxiety or depression symptoms in children with ADHD. (J. of Att. Dis. 2009; 12(6) 499-506)
Sexual dysfunction in newly diagnosed multiple sclerosis women
Authors: Tzortzis Vassilios , Skriapas Konstantinos , Hadjigeorgiou George , Mitsogiannis Iraklis , Aggelakis Konstantinos , Gravas Stavros , Poulakis Vassilios , Melekos Michael D
Published: July 2008

Objectives The aim of the study was to evaluate female sexuality in a selective population of newly diagnosed multiple sclerosis (MS) women.

Materials and methods In this clinic-based study, 63 newly diagnosed consecutive women affected by definite MS were admitted. Disability and depression were evaluated with the expanded disability status scale (EDSS) and Beck depression inventory, respectively. Sexual function was evaluated with the female sexual function index (FSFI). A group of 61 healthy female volunteers with the same baseline characteristics were used as controls. Postmenopausal women and patients with other major concomitant neurological, endocrinological, vascular, gynecological, psychiatric disorders, use of medicines that can cause female sexual dysfunction (FSD) and disease-modifying drugs were excluded from the study.

Results All the evaluated patients were ambulant with no major neurological impairment (mean EDSS score 2.5, range 0—3.5). None of the patients were considered clinically depressed, but some of them were sad or worried. According to the sexual history and FSFI scores, sexual dysfunction was diagnosed in 22 (34.9%) out of the 63 patients and in 13 (21.31%) out of the 61 healthy females ( P > 0.05).

Conclusions In the newly diagnosed MS patients, FSD represent an important issue even though disability and other concomitant disorders affecting sexual function were excluded.

Multiple Sclerosis 2008; 14: 561—563. http://msj.sagepub.com
Virtual News
Authors: Lee-Wright Peter
Published: July 2008

This article assesses the strategies of BBC News as it repositions itself for the digital future, explores how impartiality is being redefined, evaluates the impact of technology-led strategies on newsgathering and notes the tensions between rival forces inside the BBC. The corporation is engaged in an internal upheaval of seismic proportions, as technological change accelerates and the largest ever round of job losses threatens. There is a titanic struggle between the technologists — who have been rebranded as über-divisional force Future Media and Technology — and the programme makers, who feel their role and resources have been cut to make way for the new platforms. In the FMT corner, its director Ashley Highfield is making apocalyptic announcements, characterized by BBC house newspaper Ariel as `Get web savvy or we die', while programme executives are saying that the BBC needs to recognize and protect its core strengths in content provision, not pretend it can compete with the cyber-cities of Google and co. It's not future technology, it's here and now, they say, but it should not be allowed to override the values and objectives of their public service remit. This article is based on research carried out for the `Spaces of the News' research project, one of five strands of the Goldsmiths Media Research Programme, Spaces, Connectivity and Control , funded by the Leverhulme Trust, which is designed to evaluate the social impact of changes in communication technology.
Discussion Forums, Games and Second Life
Authors: Moe Hallvard
Published: July 2008

Across Western Europe, public broadcasters have built their internet presence into sprawling sites encompassing a multitude of services. This development illustrates the need for redefining the role of public service media in a digital era. The article scrutinizes dilemmas following the emerging EU competition law-inspired policy approach to public broadcasters' internet activities, and discusses the potential public service value of online communication. The article draws on three cases representing services seemingly far removed from redistribution of radio and television: an internet discussion forum (ZDF), a web-based game (NRK), and a virtual online world activity (BBC). These sometimes controversial experiments are well suited to challenge both accustomed perceptions of public service, and ideas about the potential contributions of online communication. By scrutinizing marginal parts the article explores the limits of public broadcasters' publicly funded activities. It thereby aims to revitalize the discussion about the functions of public service as a media policy tool.
Interfacing the Nation
Authors: Bennett James
Published: July 2008

This article engages with prominent arguments about the role of public service broadcasting in the digital age and suggests that the BBC's role as a national universalist provider is one that can be accommodated within an age of identity and media pluralism. Taking the BBC's 2004 coverage of commemoration events that marked the end of the Second World War as a case study, this article combines industrial and textual analysis to investigate how the BBC utilized event programming and interactive television as a `portal' to drive viewers to online spaces. In so doing, it examines how such programming strategies worked to reassert traditional public service concerns with the national whilst simultaneously exploiting its brand value across new media platforms to cater for a fragmenting audience. The forms of interactive television discussed here are characterized by a desire to bring viewers together into one space to `engage' and `participate' under the familiar terms of the national, but crucially within the new media spaces opened to them by the BBC as `trusted guide'. The conclusion outlines how this case study might help us understand a `remediation' of public service broadcasting's role in the digital age, suggesting that the BBC's 2004 commemorative programming was particularly successful in articulating this role.
Public Service Broadcasting as an Infrastructure of Translation in the Age of Cultural Diversity
Authors: Podkalicka Aneta
Published: July 2008

This article investigates a redefined socio-cultural role of European public service broadcasting as an infrastructure of translation in times of globalization, migration and the proliferation of new media providers. Drawing upon research into multilingual broadcasting in Europe and Australia, and in particular a case study of Special Broadcasting Service Australia (SBS), it argues for an ongoing relevance of European public service broadcasting (PSB), albeit within wider conceptions of translingual, transnational or European citizenship. It is proposed that of the two versions of translation, institutional in the EU and mediated in Australia respectively, the mediated version has achieved higher success in communicating diversity across hybrid communities. The main point raised here is the importance of `connections' and, within the framework of `cultural diversity' and `multilingualism' in Europe, arguably at the expense of `Europeanness'. The concept of translation allows thought beyond a single language but also beyond diversity and towards interlingual communication and `mutual intelligibility'. As such it is useful to inform a community-building media policy for Europe as a necessary alternative to the historically dominant top-down EU language policy.
Public Service Broadcasting in Converging Media Modalities
Authors: Bardoel Johannes , d'Haenens Leen
Published: July 2008

This contribution makes a case for the convergence between technologies as a basis for public access to digital cultural heritage in an age where citizens increasingly seek alternative sources of information and have the power to choose, compare, and publish opinions of their own online. The stage on which European public broadcasters perform nowadays is being thoroughly transformed, and although the preconditions for multimedia strategies seem to be much more advantageous than just a few years ago, public broadcasters will need to decide to extend their portfolio of platforms and channels if they want to reach out to all generations, including the young ones. The Dutch public broadcaster seems to adopt an active strategy in the digital domain, however, this strategy is still expressed in technological and economical terms and takes insufficient account of the viewers' present and future media use. This touches on another angle from which to view the link between public broadcasting and ICT: the necessity for PSB to capture new user groups with innovative content, consistently clustered, and in line with the public service mandate.
Health Technology Assessment in the Canadian Health Policy Arena
Authors: Lehoux Pascale , Hivon Myriam , Denis Jean-Louis , Tailliez Stéphanie
Published: July 2008

This article uses a sociopolitical perspective to analyse the results of a case study of six Canadian Health Technology Assessment (HTA) agencies and their stakeholders: health care administrators, provider associations, patient associations and the biomedical industry. A total of 40 HTA agency representatives and 46 stakeholders were interviewed.A self-administered survey was also filled out by a larger number of respondents belonging to the four groups ( n = 405). Our study indicates that the concept of HTA has gained acceptance and that several groups want their concerns and priorities to be included in the agencies' agendas. Nevertheless, stakeholders question the political autonomy of HTA agencies and their ability to bring about concrete change.This article proposes strategies that may help improve relationships and exchanges between evaluators and their stakeholders. Evaluators must not be afraid to ask for more accountability in the way health technology policies are drafted.
Evaluator's Role in Accountability Relationships
Authors: Benjamin Lehn M.
Published: July 2008

While evaluators have considered accountability pressures and examined the consequences of performance measurement for organizations, they have paid less attention to the accountability relationship in which their work is used. Drawing on theoretical literature and empirical data, this article shows how these accountability relationships drive the use of evaluative frameworks, like performance measurement, and shape the consequences for the organizations involved.The article argues that in settings permeated by accountability concerns, evaluators need to understand these accountability relationships that so significantly shape their work, especially if they hope to improve accountability systems or create the space for evaluation to serve other important purposes.This article provides evaluators with a set of questions and points of analysis that they can use to examine accountability relationships and expand what is possible for evaluation in settings where accountability is the dominant concern.
From Evaluation to Interpretation
Authors: Baerveldt Chris , Horjus Bob , De Winter Micha
Published: July 2008

Impact studies of prevention programmes, in particular meta-analyses, usually interpret outcome and impact statistics as tests of an underlying theory of prevention. However, these programmes usually combine various interventions linked to different theoretical perspectives. Consequently, the effects of the programme can easily be misinterpreted.This article introduces an interpretation method that acknowledges the eclecticism of prevention practice and is also a feasible instrument to enhance the quality of meta-studies. First, the interventions of the programme are identified and analysed separately. Second, an assessment is made of the arguments that link interventions and the espoused theories.Third, each intervention is represented by a set of scores indicating the types of links and core theoretical assumptions.These scores are aggregated to programme scores and included as independent variables in meta-analyses.The method is illustrated by an evaluation of practices in two Dutch crime prevention institutions. The evaluation demonstrated the theoretical value of (eclectic) practices, even when they differ substantially from the official programme theories.The approach also highlighted an `interpretation error' in assessing the impact of one of the programmes and suggests a correction.
Neoliberalism, welfare policy, and feminist theories of social justice
Authors: Smith Anna Marie
Published: July 2008

An overview of the feminist theory literature on welfare policy and politics is presented. This introductory essay places a particular emphasis on the works that fall within the political sociology and normative political philosophy genres. In a lengthy digression, the article offers a tribute to the work of Iris Marion Young. It examines the centrality of her thinking about distribution, cultural marginalization, the welfare state bureaucracy, transnational responsibility and solidarity, and the pitfalls of maternalist discourse for this field. In the conclusion, the article makes brief remarks about each of the contributions to the special issue on Feminist Theory and Welfare.
Neoliberalism and the jurisprudence of privacy
Authors: Mihic Sophia Jane
Published: July 2008

This essay demonstrates, and critiques, the pervasiveness of economic assumptions in the jurisprudence of privacy in US constitutional law as it extends from birth control and abortion rights to the so-called right to die. Finding in these cases metaphors of neoliberal productive practices and the assumption of the self as human capital, the self understood as a site of investment rather than a repository of worth, the essay brings privacy law into conversation with Kristin Luker's empirical work on abortion politics and teenage pregnancy. The essay does not treat the right to die as a moral or political problem to be resolved, but is instead interested in the revelatory character of the jurisprudence of privacy — namely, in what it can tell us about the contemporary political economic order. Are recent developments in contemporary political economy, in the emerging neoliberal order, potentially illiberal?
Gender justice and the welfare state in post-communism
Authors: Gheaus Anca
Published: July 2008

Some Romanian feminist scholars argue that welfare policies of post-communist states are deeply unjust to women and preclude them from reaching economic autonomy. The upshot of this argument is that liberal economic policy would advance feminist goals better than the welfare state. How should we read this dissonance between Western and some Eastern feminist scholarship concerning distributive justice? I identify the problem of dependency at the core of a possible debate about feminism and welfare. Worries about how decades of communism have shaped citizenry feed feminists' suspicion of the welfare state and fears of paternalist policies. I criticize the arguments in favour of neoliberal policies and I suggest a crucial distinction between legitimate, universal forms of human dependency and dependencies that result from particular social arrangements.
Questioning the Evidence for Service Assumptions
Authors: Reith Margaret , Lucas Caroline
Published: July 2008

• Summary: This article reports an audit of people considered for transfer from a hospice to a nursing home for end-of-life care and discusses implications for patients, families and staff.

• Findings: Moving patients to nursing homes at the end of their lives is often distressing for both patients and families and in many cases patients die within a short time of transfer. Few patients are actually transferred although many more are asked to face this possibility often creating unnecessary anxiety. This may have adverse consequences for family members' bereavement.

• Applications : There is a weak evidence base for transferring patients from hospices to nursing homes. Palliative care services assume a short in-patient stay to ration an expensive scarce resource. Assessment with social work contributions identifying complex emotional, family and bereavement consequences may allow multidisciplinary teams to justify longer hospice stays by identifying more complex needs to justify better substantive equality between patients.
Accountable Corporate Parenting
Authors: Welbourne Penelope , Dixon John
Published: July 2008

• Summary: This article explores some complex issues involved in promoting accountability in local authority public services. In the UK, a gap in accountability for services for Looked After children was identified by the High Court. We offer an analysis of policy initiatives developed in response. Citizen review, another approach to strengthening accountability in widespread use in the USA, is described and appraised.

• Findings: Accountability in services for Looked After children in the UK has been substantially improved by recent developments in law and policy. However, it is argued that the continuing absence of external review and reliance on upward accountability still leaves a flawed structure. The paucity of quality evaluation of citizen participation in US is noted, but we identify its potential to promote both outward accountability and diversity in accountability and review.

• Application: The article is a contribution to the ongoing analysis of accountability in public services, and promotes more inclusive practice in reviewing service provision. Its focus is on Looked After children, but some of the principles discussed are capable of application to other vulnerable groups and communities.
The Use of Client-side Paradata in Analyzing the Effects of Visual Layout on Changing Responses in Web Surveys
Authors: Stern Michael J.
Published: July 2008

Recent research has shown that even minor changes in the visual layout of survey questions can affect the way in which respondents answer. Still, little is known about how these changes affect the actual answering process. The recent development of client-side paradata allows us to better understand the way respondents construct their answers by providing new types of data, including time taken to answer a question and whether respondents change their answers. Although a number of studies have used this technology to examine response latency, few have taken advantage of its potential to collect data on the types of changes respondents make while answering survey questions. This study uses client-side paradata to analyze changes in multiple versions of three types of Web survey questions. The results suggest that the visual layout of survey questions not only affects the number but also the types of changes respondents make.
The Effects of Media Interpretation for Citizen Evaluations of Politicians' Messages
Authors: Fogarty Brian J. , Wolak Jennifer
Published: July 2008

Although politicians prefer to communicate directly with the public, political sound bites in the nightly news are shrinking and primetime presidential press conferences are becoming increasingly uncommon. Instead, people primarily receive the messages of politicians as interpreted by journalists. What are the consequences of this interpretation for how citizens evaluate political messages? This article compares how people evaluate mediated political accounts and those delivered by politicians directly. Using a set of experiments, this article considers whether the power of politicians to inform and persuade people is limited or enhanced through the interpretation of journalists. This article finds that although people respond similarly to message content, whether from the politicians or from the media, evaluations of the message source and political processes are improved when politicians communicate directly with the public.
Combined Insomnia and Poor CPAP Compliance
Authors: Wickwire Emerson M. , Schumacher Julie A. , Richert Alan C. , Sinan Baran A. , Roffwarg Howard P.
Published: July 2008

This report describes the case of Samuel, a Caucasian man in his early sixties who self-referred to a behavioral insomnia clinic at a university medical center. Samuel had recently been diagnosed with obstructive sleep apnea and had been prescribed continuous positive air pressure (CPAP) therapy for this condition. At the time he presented for treatment, he was non-compliant with his CPAP prescription and maintained that the physician who diagnosed obstructive sleep apnea was mistaken. His presenting complaint to the insomnia clinic was a 25-year history of difficulty initiating sleep, which he believed was the sole cause of his problem with daytime sleepiness. In addition to his obstructive sleep apnea, Samuel was diagnosed with obstructive sleep apnea and psychophysiological insomnia. The treatments selected were a motivational enhancement treatment for CPAP compliance and a cognitive-behavioral intervention for insomnia. Treatments were presented in a combined, sequential fashion. At treatment follow-up, Samuel reported increased CPAP compliance, decreased daytime sleepiness, and decreased insomnia severity.
Social Skills Group Therapy for Autism Spectrum Disorders
Authors: Ruble Lisa , Willis Heather , McLaughlin Crabtree Valerie
Published: July 2008

More examples for clinicians are needed on the implementation of data-driven intervention approaches for autism spectrum disorders (ASDs). The purpose of this case study is to present a feasible data-driven approach using a pre- and postdesign of an outpatient social skills group for children with ASD who were clinically referred rather than research recruited for services. Measurement tools with ecological validity are described, as are the treatment outcomes. Challenges included the generation of meaningful and obtainable outcomes with social validity and the development of feasible methods to evaluate clinical outcomes. Practical issues related to implementation are described that can increase researchers' understanding of the practitioner environment, and suggestions are made for data-driven methods for service delivery monitoring, accountability, and scalability.
The Behavioral Treatment of an 11-Year-Old Girl With Autism and Aggressive Behaviors
Authors: Matson Johnny L. , LoVullo Santino V. , Boisjoli Jessica A. , Gonzalez Melissa L.
Published: July 2008

The authors describe the assessment and treatment of an 11-year-old girl who presented with autism and aggressive behaviors. Based on a functional analysis and review of relevant literature, differential reinforcement of other behaviors (DRO), compliance training, extinction, and functional communication were used as the primary intervention strategies. This case also illustrates the importance of creating a plan for generalization and the challenges parents face when trying to incorporate treatment strategies into the home environment. The importance of an accurate diagnosis and appropriate behavioral treatment are emphasized as a protection against the misuse of psychotropic medications and psychological interventions.
A molecular signaling model of platelet phosphoinositide and calcium regulation during homeostasis and P2Y1 activation
Authors: Purvis Jeremy E. , Chatterjee Manash S. , Brass Lawrence F. , Diamond Scott L.
Published: July 2008

To quantify how various molecular mechanisms are integrated to maintain platelet homeostasis and allow responsiveness to adenosine diphosphate (ADP), we developed a computational model of the human platelet. Existing kinetic information for 77 reactions, 132 fixed kinetic rate constants, and 70 species was combined with electrochemical calculations, measurements of platelet ultrastructure, novel experimental results, and published single-cell data. The model accurately predicted: (1) steady-state resting concentrations for intracellular calcium, inositol 1,4,5-trisphosphate, diacylglycerol, phosphatidic acid, phosphatidylinositol, phosphatidylinositol phosphate, and phosphatidylinositol 4,5-bisphosphate; (2) transient increases in intracellular calcium, inositol 1,4,5-trisphosphate, and Gq-GTP in response to ADP; and (3) the volume of the platelet dense tubular system. A more stringent test of the model involved stochastic simulation of individual platelets, which display an asynchronous calcium spiking behavior in response to ADP. Simulations accurately reproduced the broad frequency distribution of measured spiking events and demonstrated that asynchronous spiking was a consequence of stochastic fluctuations resulting from the small volume of the platelet. The model also provided insights into possible mechanisms of negative-feedback signaling, the relative potency of platelet agonists, and cell-to-cell variation across platelet populations. This integrative approach to platelet biology offers a novel and complementary strategy to traditional reductionist methods.
Cardiac autonomic activity and blood pressure among Nunavik Inuit adults exposed to environmental mercury: a cross-sectional study
Authors: Valera Beatriz , Dewailly Eric , Poirier Paul
Published: July 2008

Background

Mercury is a contaminant that reaches high levels in Nunavik (North of Quebec). It is transformed into methylmercury (MeHg) and accumulated in marine mammals and predator fish, an important part of the traditional Inuit diet. MeHg has been suggested to affect BP in adults and children while the influence on HRV has only been studied in children. We aimed to assess the impact of MeHg levels on HRV and BP in Inuit adults from Nunavik.

Methods

In the fall of 2004, the «Qanuippitaa?» Health Survey was conducted in Nunavik (Quebec, Canada) and information on HRV was collected among 280 adults aged 40 years and older. Indicators of the time and frequency domains of HRV were derived from a 2-hour Holter recording. BP was measured according to the Canadian Coalition for High Blood Pressure technique. Pulse pressure (PP) was the difference between systolic (SBP) and diastolic blood pressure (DBP). Blood mercury concentration was used as exposure biomarker. Statistical analysis was conducted through linear regression and multivariable linear regression was used to control for confounders.

Results

Mercury was negatively correlated with low frequency (LF) (r = -0.18; p = 0.02), the standard deviation of RR intervals (SDNN) (r = -0.14; p = 0.047) and the coefficient of variation of RR intervals (CVRR) (r = -0.18; p = 0.011) while correlations with other HRV parameters did not reach statistical significance. After adjusting for confounders, the association with LF (beta = -0.006; p = 0.93) became non significant. However, the association with SDANN became statistically significant (beta = -0.086; p = 0.026) and CVRR tended to decrease with blood mercury concentrations (beta = -0.057; p = 0.056). Mercury was positively correlated with SBP (r = 0.25; p < 0.0001) and PP (r = 0.33; p < 0.0001). After adjusting for confounders, these associations remained statistically significant (beta SBP = 4.77; p = 0.01 and beta PP = 3.40; p = 0.0036). Moreover, most of the HRV parameters correlated well with BP although SBP the best before adjustment for mercury exposure.

Conclusion

The results of this study suggest a deleterious impact of mercury on BP and HRV in adults. SBP and PP increased with blood mercury concentrations while SDANN decreased with blood mercury concentrations.
Risk prediction models with incomplete data with application to prediction of estrogen receptor-positive breast cancer: prospective data from the Nurses' Health Study
Authors: Rosner Bernard , Colditz Graham A , Iglehart J Dirk , Hankinson Susan E
Published: July 2008

Introduction

A number of breast cancer risk prediction models have been developed to provide insight into a woman's individual breast cancer risk. Although circulating levels of estradiol in postmenopausal women predict subsequent breast cancer risk, whether the addition of estradiol levels adds significantly to a model's predictive power has not previously been evaluated.

Methods

Using linear regression, the authors developed an imputed estradiol score using measured estradiol levels (the outcome) and both case status and risk factor data (for example, body mass index) from a nested case-control study conducted within a large prospective cohort study and used multiple imputation methods to develop an overall risk model including both risk factor data from the main cohort and estradiol levels from the nested case-control study.

Results

The authors evaluated the addition of imputed estradiol level to the previously published Rosner and Colditz log-incidence model for breast cancer risk prediction within the larger Nurses' Health Study cohort. The follow-up was from 1980 to 2000; during this time, 1,559 invasive estrogen receptor-positive breast cancer cases were confirmed. The addition of imputed estradiol levels significantly improved risk prediction; the age-specific concordance statistic increased from 0.635 ± 0.007 to 0.645 ± 0.007 (P < 0.001) after the addition of imputed estradiol.

Conclusion

Circulating estradiol levels in postmenopausal women appear to add to other lifestyle factors in predicting a woman's individual risk of breast cancer.
An optimal approach to non-linear control of vehicle yaw dynamics
Authors: Mirzaei M , Alizadeh G , Eslamian M , Azadi S
Published: July 2008

Direct yaw moment control (DYC) is a recent active safety method introduced to control vehicle handling dynamics in non-linear regimes. The external yaw moment is considered as an important control input for DYC, which should be kept as low as possible. In the current paper, to achieve this aim, an optimal yaw rate tracking law is developed for DYC by the response prediction of a continuous non-linear vehicle dynamics model. A linear yaw rate model limited by tyre/road conditions is proposed as a desired model to be tracked by the controller. The derived control law is evaluated and its main features are discussed. The performed analysis gives an insight into the regulation of free parameters of the control law to make a compromise between tracking accuracy and control energy. The effectiveness of the designed controller is compared with a sliding mode controller, reported in literature, through simulations of various manoeuvres using a developed non-linear full vehicle dynamics model. The simulation results indicate that a satisfactory handling performance through a reduced external yaw moment can be achieved when the proposed optimal controller is engaged with the model.
Bond graph model of a solid oxide fuel cell with a C-field for mixture of two gas species
Authors: Vijay P , Samantaray A K , Mukherjee A
Published: July 2008

A true bond graph model of a solid oxide fuel cell (SOFC) is presented in this paper. The constitutive relations of a C-field for two species of gases are formulated in order to model the cathode and the anode channels of the fuel cell. Moreover, an existing R-field model has been extended for modelling of forced convection of a mixture of two gas species. For given values of system operating pressure, the air source and hydrogen source pressures, the outlet pressures and the inlet gas compositions, the fuel utilization (FU), and air utilization (AU) are interpreted in terms of the partial pressures of the gases in the anode channel and cathode channel. The model is simulated and various static and dynamic characteristic curves for the SOFC are obtained. It is found that the model is capable of capturing all the essential dynamics of the SOFC. Availability of this bond graph model will aid in designing robust model-based control strategies for the fuel cell system and also for performing exergy analysis of the system.
Robust and decoupled cascaded control system of underwater robotic vehicle for stabilization and pipeline tracking
Authors: Chin C S , Lau M W S , Low E , Seet G G L
Published: July 2008

The current paper proposes a robust and decoupled cascaded control system with output feedback control for simultaneous stabilization and pipeline tracking of a remotely operated vehicle (ROV) under hydrodynamic uncertainties. One of the ROV applications on the simultaneous stabilization and tracking was global output feedback with backstepping method on an ODIN ROV. However, the controller design becomes complex, as partial differential equations are required in the backstepping control law and the ROVs is inherently non-linear, highly coupled in motion, unsymmetrical in vehicle design, and vulnerable to hydrodynamic uncertainties. Compared with the backstepping control and other controllers, the computer simulation shows that the proposed method is simpler and performed better in time domain response and other performance measures such as robustness and stability.
Spliceosomal snRNAs in the unicellular eukaryote Trichomonas vaginalis are structurally conserved but lack a 5′-cap structure
Authors: Simoes-Barbosa Augusto , Meloni Dionigia , Wohlschlegel James A. , Konarska Maria M. , Johnson Patricia J.
Published: July 2008

Few genes in the divergent eukaryote Trichomonas vaginalis have introns, despite the unusually large gene repertoire of this human-infective parasite. These introns are characterized by extended conserved regulatory motifs at the 5′ and 3′ boundaries, a feature shared with another divergent eukaryote, Giardia lamblia, but not with metazoan introns. This unusual characteristic of T. vaginalis introns led us to examine spliceosomal small nuclear RNAs (snRNAs) predicted to mediate splicing reactions via interaction with intron motifs. Here we identify T. vaginalis U1, U2, U4, U5, and U6 snRNAs, present predictions of their secondary structures, and provide evidence for interaction between the U2/U6 snRNA complex and a T. vaginalis intron. Structural models predict that T. vaginalis snRNAs contain conserved sequences and motifs similar to those found in other examined eukaryotes. These data indicate that mechanisms of intron recognition as well as coordination of the two catalytic steps of splicing have been conserved throughout eukaryotic evolution. Unexpectedly, we found that T. vaginalis spliceosomal snRNAs lack the 5′ trimethylguanosine cap typical of snRNAs and appear to possess unmodified 5′ ends. Despite the lack of a cap structure, U1, U2, U4, and U5 genes are transcribed by RNA polymerase II, whereas the U6 gene is transcribed by RNA polymerase III.
Conformationally restricted nucleotides as a probe of structure–function relationships in RNA
Authors: Julien Kristine R. , Sumita Minako , Chen Po-Han , Laird-Offringa Ite A. , Hoogstraten Charles G.
Published: July 2008

We introduce the use of commercially available locked nucleic acids (LNAs) as a functional probe in RNA. LNA nucleotides contain a covalent linkage that restricts the pseudorotation phase of the ribose to C3′-endo (A-form). Introduction of an LNA at a single site thus allows the role of ribose structure and dynamics in RNA function to be assessed. We apply LNA probing at multiple sites to analyze self-cleavage in the lead-dependent ribozyme (leadzyme), thermodynamic stability in the UUCG tetraloop, and the kinetics of recognition of U1A protein by U1 snRNA hairpin II. In the leadzyme, locking a single guanosine residue into the C3′-endo pucker increases the catalytic rate by a factor of 20, despite the fact that X-ray crystallographic and NMR structures of the leadzyme ground state reported a C2′-endo conformation at this site. These results strongly suggest that a conformational change at this position is critical for catalytic function. Functional insights obtained in all three systems demonstrate the highly general applicability of LNA probing in analysis of the role of ribose orientation in RNA structure, dynamics, and function.
A Screening Model for CO2 Flooding and Storage in Gulf Coast Reservoirs Based on Dimensionless Groups
Authors: Wood Derek J. , Lake Larry W. , Johns Russell T. , Nunez Vanessa
Published: July 2008

Concerns over global warming have led to interest in removing greenhouse gases, specifically CO2, from the atmosphere. Sequestration of CO2 in oil reservoirs as part of enhanced oil recovery (EOR) projects is one method that is being considered.

This paper first presents the scaling groups necessary to describe CO2 flooding for a typical line-drive pattern and then uses these groups in a Box-Behnken experimental design to create a screening model most applicable to candidate Gulf Coast reservoirs (Box and Behnken 1960). By generating oil recovery and CO2 storage curves, the model estimates the cumulative oil recovery and CO2 storage potential for a given reservoir. Past screening models—Rivas et al. (1992) and Diaz et al. (1996)—focused only on oil recovery and simply assigned qualitative rankings to reservoirs. Models that did include quantitative results, including CO2 Prophet (Dobitz and Prieditis 1994) and the CO2 Predictive Model (Paul et al. 1984), did not include the effects of dip. This model focuses on both oil recovery and CO2 storage potential, produces quantitative results for each, and includes the effects ofdip.

This model quickly estimates the oil recovery and CO2 storage potential for a reservoir. Operators can quickly screen large databases ofreservoirs to identify the best candidates for CO2 flooding and storage. The scaling groups also provide the basis for future models that may be more specific to other regions.

The results show that continuous CO2 flooding can be fully described using 10 dimensionless groups: aspect ratio, dip angle group, water and CO2 mobility ratios, buoyancy number, dimensionless injection and producing pressures, residual oil saturation to water and gas, and initial oil saturation. The effects ofcapillary forces and dispersion were secondary effects in this model and were not included in the scaling. Dimensionless oil recovery was effectively modeled with the dimensionless oil breakthrough time and the dimensionless recovery at three different dimensionless times, while CO2 storage potential was calculated only at the final dimensionless time. The reservoir-specific parameters discussed above were calculated from response surface fits. The scaling does not work as well at small buoyancy numbers; however, it is effective in the range of values typical of Gulf Coast reservoirs.
Downhole Fluid Analysis and Fluid-Comparison Algorithm as Aid to Reservoir Characterization
Authors: Venkataramanan Lalitha , Elshahawi Hani , McKinney Daniel , Flannery Matthew , Hashem Mohammed , Mullins Oliver C.
Published: July 2008

In recent years, formation-sampling and formation-testing tools have provided a variety of new downhole optical measurements for downhole fluid analysis (DFA). DFA involves an in-situ measurement of optical absorption spectra used to compute properties such as hydrocarbon composition and gas/oil ratio (GOR). Abrupt changes in these fluid properties with depth may be markers for reservoir compartmentalization. However, hydrocarbon differences can be identified reliably only when the significance of uncertainties from measurement and the oil-based mud (OBM) filtrate have been taken into account. Recently, an algorithm called the fluid-comparison algorithm (FCA) was developed to address this issue.

The FCA propagates uncertainties in optical measurement and contamination into uncertainties in fluid properties, such as color, composition, and GOR. The output of the FCA is the probability that two fluids are statistically different. Real-time application of the FCA can optimize capture of downhole-fluid samples and generation of a continuous downhole-fluid log representing the fluid complexity in the reservoir. In addition, by identifying abrupt changes in fluid properties that occur with depth, the FCA may in some circumstances be an assay for reservoir compartmentalization.

In this paper, we briefly review the theory of the FCA. The strengths and limitations of the technique for an improved understanding of reservoir architecture and fluid complexities are presented in two case studies.