bluuebunny/crossref_metadata_2025 huggingface dataset:
Prediction of Arrhythmic Events in Ischemic and Dilated Cardiomyopathy Patients Referred for Implantable Cardiac Defibrillator
Authors: Gao Peng , Yee Raymond , Gula Lorne , Krahn Andrew D. , Skanes Allan , Leong-Sit Peter , Klein George J. , Stirrat John , Fine Nowell , Pallaveshi Luljeta , Wisenberg Gerald , Thompson Terry R. , Prato Frank , Drangova Maria , White James A.
Published: May 2012

Background—

Scar signal quantification using late gadolinium enhancement cardiac magnetic resonance (LGE-CMR) identifies patients at higher risk of future events, both in ischemic cardiomyopathy (ICM) and nonischemic dilated cardiomyopathy (DCM). However, the ability of scar signal burden to predict events in such patient groups at the time of referral for implantable cardioverter-defibrillator (ICD) has not been well explored. This study evaluates the predictive use of multiple scar quantification measures in ICM and DCM patients being referred for ICD.

Methods and Results—

One hundred twenty-four consecutive patients referred for ICD therapy (59 with ICM and 65 with DCM) underwent a standardized LGE-CMR protocol with blinded, multithreshold scar signal quantification and, for those with ICM, peri-infarct signal quantification. Patients were followed prospectively for the primary combined outcome of appropriate ICD therapy, survived cardiac arrest, or sudden cardiac death. At a mean follow-up of 632 ± 262 days, 18 patients (15%) had suffered the primary outcome. Total scar was significantly higher among those suffering a primary outcome, a relationship maintained within each cardiomyopathy cohort (
P
<0.01 for all comparisons). Total scar was the strongest independent predictor of the primary outcome and demonstrated a negative predictive value of 86%. In the ICM subcohort, peri-infarct signal showed only a nonsignificant trend toward elevation among those having a primary end point.

Conclusions—

Myocardial scar quantification by LGE-CMR predicts arrhythmic events in patients being evaluated for ICD eligibility irrespective of cardiomyopathy etiology.
Biochemistry, Physiology, and Pathophysiology of NADPH Oxidases in the Cardiovascular System
Authors: Lassègue Bernard , San Martín Alejandra , Griendling Kathy K.
Published: May 2012

atherosclerosis, hypertension, cardiac hypertrophy and remodeling, angiogenesis and collateral formation, stroke, and heart failure. In this review, we discuss in detail the biochemistry of Nox enzymes expressed in the cardiovascular system (Nox1, 2, 4, and 5), their roles in cardiovascular cell biology, and their contributions to disease development.
Ticagrelor Versus Clopidogrel in Patients With Acute Coronary Syndromes and a History of Stroke or Transient Ischemic Attack
Authors: James Stefan K. , Storey Robert F. , Khurmi Nardev S. , Husted Steen , Keltai Matyas , Mahaffey Kenneth W. , Maya Juan , Morais Joao , Lopes Renato D. , Nicolau Jose C. , Pais Prem , Raev Dimitar , Lopez-Sendon Jose L. , Stevens Susanna R. , Becker Richard C.
Published: May 2012

Background—

Patients with acute coronary syndromes and history of stroke or transient ischemic attack (TIA) have an increased rate of recurrent cardiac events and intracranial hemorrhages.

Methods and Results—

We evaluated treatment effects of ticagrelor versus clopidogrel in patients with acute coronary syndrome with and without a history of prior stroke or TIA in the PLATelet inhibition and patient Outcomes (PLATO) trial. Of the 18 624 randomized patients, 1152 (6.2%) had a history of stroke or TIA. Such patients had higher rates of myocardial infarction (11.5% versus 6.0%), death (10.5% versus 4.9%), stroke (3.4% versus 1.2%), and intracranial bleeding (0.8% versus 0.2%) than patients without prior stroke or TIA. Among patients with a history of stroke or TIA, the reduction of the primary composite outcome and total mortality at 1 year with ticagrelor versus clopidogrel was consistent with the overall trial results: 19.0% versus 20.8% (hazard ratio, 0.87; 95% confidence interval, 0.66–1.13; interaction
P
=0.84) and 7.9% versus 13.0% (hazard ratio, 0.62; 95% confidence interval, 0.42–0.91). The overall PLATO-defined bleeding rates were similar: 14.6% versus 14.9% (hazard ratio, 0.99; 95% confidence interval, 0.71–1.37), and intracranial bleeding occurred infrequently (4 versus 4 cases, respectively).

Conclusions—

Patients with acute coronary syndrome with a prior history of ischemic stroke or TIA had higher rates of clinical outcomes than patients without prior stroke or TIA. However, the efficacy and bleeding results of ticagrelor in these high-risk patients were consistent with the overall trial population, with a favorable clinical net benefit and associated impact on mortality.

Clinical Trial Registration—

URL:
http://www.clinicatrials.gov
. Unique identifier: NCT00391872.
Upstream-Propagating Wave Modes in Moist and Dry Flow over Topography
Authors: Keller Teddie L. , Rotunno Richard , Steiner Matthias , Sharman Robert D.
Published: May 2012

Previous studies have observed upstream-propagating modes in two-dimensional numerical simulations of idealized flow over topography with moist, nearly neutral conditions in the troposphere, topped by a stable stratosphere. The generation and propagation mechanisms for these modes were attributed to localized and dramatic changes in stability induced by the desaturation of the flow impinging on the mountain. In the present paper it is shown that these modes are transient upstream-propagating gravity waves, which are a fundamental feature of both moist and dry flow over topography of a two-layer troposphere–stratosphere atmospheric profile impulsively started from rest. The mode selection and propagation speeds of these transient waves are highly dependent on the tropospheric stability, as well as the wind speed and tropopause depth. In the moist case these modes appear to propagate according to an effective static stability that is intermediate to the normal dry stability and the lower moist stability. Comparisons with the linear, time-dependent, hydrostatic analytic solution show that these modes are similar to the transients observed in flow of a constant wind and stability layer over topography with a rigid upper boundary.
Validating IASI Temperature and Moisture Sounding Retrievals over East Asia Using Radiosonde Observations
Authors: Kwon Eun-Han , Sohn B. J. , Smith William L. , Li Jun
Published: May 2012

Temperature and moisture profiles retrieved from Infrared Atmospheric Sounding Interferometer (IASI) data are evaluated using collocated radiosonde data from September 2008 to August 2009 over East Asia. The level-2 products used in this study were provided by the National Oceanic and Atmospheric Administration/National Environmental Satellite, Data, and Information Service. By using radiosonde observations as a reference, the bias and root-mean-square error (RMSE) of the temperature and water vapor profiles are obtained to examine the performance of the IASI retrievals depending on surface types and the degree of atmospheric moisture. Overall, retrievals over the land or under drier atmospheric conditions show degraded performance for both the temperature and the moisture, especially for the boundary layer temperature. It is further shown that the vertical distributions of the RMSEs and the biases of the IASI retrievals resemble the variability pattern of the radiosonde observations from the mean profiles. These retrieval aspects are thought to be related to the surface emissivity effect on the IASI retrieval and the difficulties of accounting for large atmospheric variability in the retrieval process. Although the retrieval performance appears to degrade under cloudy conditions, cloudy- and clear-sky retrievals show similar statistical behaviors varying with surface type and atmospheric moisture. Furthermore, the similar statistical behaviors between first guess and final retrievals suggest that error characteristics inherent to the first guess were not sufficiently resolved by the physical retrieval process, leaving a need to improve the first guess for the better retrieval.
Designs for Studying the Effectiveness of Long-Term Psychoanalytic Treatments
Authors: de Jonghe Frans , de Maat Saskia , Barber Jacques P. , Abbas Allan , Luyten Patrick , Gomperts Wouter , Swinkels Jan , Dekker Jack
Published: May 2012

Long-Term Psychoanalytic Treatments (LTPT) include both long-term psychoanalytic psychotherapy (LTPP) and psychoanalysis (PsAn). Current opinion seems to be that there is some evidence for the effectiveness of LTPP, but none for that of PsAn. This may be due in part to researchers not balancing the level of evidence of randomized controlled studies (RCTs), cohort studies, and pre-post studies with patients’ acceptance of these various research designs used in studying the effectiveness of LTPT. After a review of the merits of eight possible control conditions for LTPT in RCTs and cohort studies, and a consideration of the limitations and merits of pre-post studies, it was found that RCTs pair high levels of evidence with limited degrees of patient acceptance, especially where PsAn is concerned. Cohort studies appear to provide at most a moderate level of evidence. Their acceptability is hardly better than that of RCTs, as it depends on the acceptability of control conditions similar to those of RCTs. The acceptability of pre-post studies is much better, but they can provide, at most, a moderate level of evidence. Apart from randomization, they can meet all methodological criteria for high-quality research (often they do not, but there are ways to correct this). In summary, in the long-term treatment of complex mental disorders with LTPT, RCTs often pair a high level of evidence with limited patient acceptance of the method. Compared to RCTs, cohort studies show a lower level of evidence without much gain in acceptability. Pre-post studies pair the highest level of acceptability with the lowest level of evidence of the three designs. Limited acceptability is not to be confused with no acceptability, nor moderate level of evidence with none
The Variance of Intraclass Correlations in Three- and Four-Level Models
Authors: Hedges Larry V. , Hedberg E. C. , Kuyper Arend M.
Published: May 2012

Intraclass correlations are used to summarize the variance decomposition in populations with multilevel hierarchical structure. There has recently been considerable interest in estimating intraclass correlations from surveys or designed experiments to provide design parameters for planning future large-scale randomized experiments. The large sample distribution of estimates of the intraclass correlation in two-level situations is well known. Contemporary educational and social experiments often involve sampling designs with three or four levels of nesting, leading to three- and four-level intraclass correlation structures. The present article provides expressions for the large sample variances and covariances of estimates of three- and four-level intraclass correlation structures.
The Value of Trees
Authors: Jones Robert Emmet , Davis Kimberly L. , Bradford John
Published: May 2012

The article discusses the value and importance of urban trees and factors that significantly influence public support for protecting them. These factors were identified by examining mail survey data obtained from a representative sample of 800 homeowners living in a rapidly urbanizing area within Southern Appalachia. A series of multiple regression analysis tested an Integrated Model of Urban Tree Support that combines measures of attitudes, beliefs, values, and sociodemographic variables to predict homeowner support for local urban tree protection. The findings lend support to many features of the model and revealed that homeowners who have stronger protree attitudes, have greater environmental concerns, place more importance on trees when looking for a new place to live, attribute symbolic value and meaning to them are more supportive. Women and Democrats are also more supportive. Recommendations are offered for future research and policy.
Identity Struggles in Merging Organizations
Authors: Langley Ann , Golden-Biddle Karen , Reay Trish , Denis Jean-Louis , Hébert Yann , Lamothe Lise , Gervais Julie
Published: May 2012

Mergers as a type of organizational change call attention to questions of identity. In this article, the authors ask: How do people collectively reconstitute their group identities for themselves and others, and in particular, how do they renegotiate understandings of sameness and difference called into question by merging? The authors draw on qualitative case data from two different merger contexts within the health care sector to develop rich descriptions and a deeper understanding of the identity struggles of four groups of employees. They identified four patterns of identity work ranging from more proactive forms of positioning as “mavericks” or fighters” to more passive forms as “adapters” or “victims” as each group struggled to navigate an altered, fluid, and emerging landscape of potential resources for self-understanding and affiliation. The authors show how identity regulation and identity work manifest themselves in three domains of language, practices and space, and how identity regulation and identity work mutually interact. Thus, the negotiation of identity in merging is a dialectic process in which managerial identity regulation aimed at enhancing convergence across groups may be undermined both by groups’ attempts to reestablish differences and by a countervailing managerial need to accommodate (and thus sustain) differences in order to enable groups to locate themselves in the emerging entity.
Fabrication and characteristics of Al6061/SiC/Gr hybrid composites processed by in situ powder metallurgy method
Authors: Mahdavi S , Akhlaghi F
Published: May 2012

A new method, namely in situ powder metallurgy, is applied for preparation of Al6061/SiC/Gr hybrid composites containing 20 vol.% of SiC particles with average sizes of 19, 93 and 146 µm, along with 0–13 vol.% uncoated graphite particles. For this purpose, SiC and graphite particles were added to molten aluminum alloy and the resultant slurries were stirred at 710°C for 8 min. During the stirring process, SiC and graphite particles disintegrated in the molten alloy, resulting in a mixture of SiC, graphite and aluminum alloy powder particles. After melt solidification, the powder mixtures were cold-pressed, sintered and heat-treated to obtain Al/SiC/Gr hybrid composites. Scanning electron microscope micrographs indicated a uniform distribution of SiC and graphite particles within the powder mixtures and hybrid composites. Moreover, smaller and more irregular-shaped aluminum particles were produced using finer SiC particles. The increased SiC particle size and graphite content resulted in improved compressibility of powder mixtures and decreased hardness of the hybrid composites. The improved wear resistance of these hybrid composites was obtained by using 5 vol.% graphite along with increased size of SiC particles.
Predicting the elastic moduli of three-dimensional (four-step) braided tubes using a spatial spring model
Authors: Hwan Chung-Li , Tsai K-H , Chen Wen-Liang , Sun SJ
Published: May 2012

In the past, the fiber bundles were mostly meshed for computing the mechanical properties of the unit cell in fabric composites. Consequently, not only the degrees of freedom but also the complexities in computation are increased. To improve the efficiency in analysis, in this study, a previously developed spring model was extended to predict the effective elastic moduli of three-dimensional (four-step) braided tubes. In the meanwhile, a related compression test was conducted to validate the computational results. It is shown that the results from the computation agree well with the experimental results. In addition, the effects of fabric parameters (such as surface braid angle and fiber volume fraction in a fan-shaped unit cell) on the effective elastic moduli of three-dimensional (four-step) braided tubes were also investigated.
Statistical design of polymeric composites reinforced with banana fibres and silica microparticles
Authors: Silva LJ , Panzera TH , Velloso VR , Rubio JCC , Christoforo AL , Scarpa F
Published: May 2012

The study describes a design of experiment analysis performed on hybrid polymeric composites reinforced with unidirectional banana fibres and silica microparticles. Maleic anhydride was also evaluated as a chemical additive to improve the adhesion between phases. A full factorial design (2231) and the analyses of variance were performed to identify the significance of the microstructure constituents against different mechanical and physical properties in a total population of 120 biocomposites samples. The microstructure parameters considered were fibre volume fraction (30% and 50%), silica addition (0%, 20 wt% and 33 wt%) and maleic anhydride addition (0% and 2 wt%). The mechanical and physical properties of the composite considered as factorial and analyses of variance responses were the apparent density, apparent porosity, water absorption, modulus of elasticity and mechanical strength under tensile and flexural loading. The design of experiment analysis has shown that the volume fraction of the fibres significantly affects all responses, with the composite made from 30% of banana fibres exhibiting superior mechanical strength and modulus of elasticity. While the addition of silica has featured a statistically noticeable contribution to the porosity and the water absorption, the presence of the particles did not provide any significant enhancement to the composites mechanical strength. Maleic anhydride showed a significant contribution to the apparent density, water absorption and flexural modulus, not improving the adhesion between phases, with a consequent decrease of the Young’s modulus and increase of the water absorption within the composites.
Norming Suburban
Authors: Watson Dyan
Published: May 2012

This study explores teachers’ beliefs about urban students and urban teaching. The author discusses some cultural aspects of these teachers’ definitions of urban and points out their highlighting of race as an essential component of urban teaching. Even though race is rarely named, it is often at play in the teachers’ descriptions of urban teaching. The author introduces the phenomenon of norming suburban and demonstrates that implicit beliefs about teaching students of color dominate these teachers’ definitions and descriptions of urban teaching.
Correctional Administrators’ Perceptions of Prison Nurseries
Authors: Campbell Julie , Carlson Joseph R.
Published: May 2012

As more pregnant women are incarcerated, states are forced to determine the most cost-efficient methods of addressing childbirth and motherhood in prison. Traditionally, newborn babies are removed from the prison setting, and their mothers, within a few days. Research shows that women who are allowed to keep their babies with them in the correctional setting have reduced recidivism rates. This study explores perceptions of the prison nursery as a form of correctional programming. Correctional administrators from all 8 states currently operating nursery programs were interviewed, as were administrators from 20 states that do not have prison nurseries ( N = 28). Findings indicate that barriers to the implementation of prison nursery programs include a lack of knowledge about these programs and the impact they have on recidivism rates, concerns about legislative budgeting given current economic conditions, and for a small number of administrators, the consequences of housing infants within the prison environment.
A Comprehensive Review of the Carcinogenic and Anticarcinogenic Potential of Capsaicin
Authors: Bley Keith , Boorman Gary , Mohammad Bashir , McKenzie Donald , Babbar Sunita
Published: May 2012

Human exposure to capsaicin, the most abundant pungent chili pepper component, is ubiquitous. Evaluation of capsaicin’s carcinogenic potential has produced variable results in in vitro and in vivo genotoxicity and carcinogenicity assays. The capsaicin tested in older studies was often from pepper plant extracts and included other capsaicinoids and diverse impurities. Recent studies utilizing high-purity capsaicin and standardized protocols provide evidence that the genotoxic and carcinogenic potential of capsaicin is quite low and that the purity of capsaicin is important. Several small epidemiological studies suggest a link between capsaicin consumption and stomach or gall bladder cancer, but contamination of capsaicin-containing foods with known carcinogens renders their interpretation problematic. The postulated ability of capsaicin metabolites to damage DNA and promote carcinogenesis remains unsupported. Anticancer activities of capsaicin have been widely reported, as it inhibits the activity of carcinogens and induces apoptosis in numerous cancer cell lines in vitro and explanted into rodents. Diverse mechanisms have been postulated for capsaicin’s anticancer properties. One hypothesis is that inhibition of cytochrome P450 enzymes—particularly CYP2E1—retards carcinogen activation but is contradicted by the low potency of capsaicin for CYP inhibition. The potential for dietary capsaicin to act as a chemopreventative is now widely postulated.
Understanding the Gender–Pay Gap in the Federal Workforce Over the Past 20 Years
Authors: Bolitzer Benjamin , Godtland Erin M.
Published: May 2012

This article examines how the pay gap between men and women in the federal workforce changed over the period 1988-2007 and what factors contributed to the pay gap. To do this, we use a decomposition method to analyze the most recent data available for a representative sample of federal employees. We find that the pay gap—the difference between men’s and women’s average pay before controlling for factors that affect pay—declined dramatically over the 20-year period. Most of this decline is because women and men in the federal workforce have become more similar over time in their levels of education and work experience and the jobs they perform in the federal government.
Bringing Hope and Change
Authors: Umamaheswar Janani
Published: May 2012

Although youth probation (in some countries described as youth justice or youth offending work) has been widely discussed in older and more recent criminological literature, less attention has been paid to youth probation officers’ accounts of their attitudes and strategies. In this study, the author uses in-depth interviews with 20 youth probation officers in Toronto, examining officers’ attitudes toward the youth they work with and how these attitudes are reflected in the strategies that the officers use to achieve their professional goals. Findings reveal that the officers balance their authoritative and supportive roles not only to hold youth accountable, to encourage them to assert control over their lives, and to maintain optimism about the possibility of a nondeviant life, but also to assist the youth in attaining the means and resources necessary to make positive changes. These findings are interpreted within the framework of Canadian youth justice legislation as well as the broader desistance literature.
Essay-Writing Strategy for Students Enrolled in a Postsecondary Program for Individuals With Developmental Disabilities
Authors: Woods-Groves Suzanne , Therrien William J. , Hua Youjia , Hendrickson Jo M.
Published: May 2012

This study investigated the efficacy of a writing (ANSWER) strategy to improve the essay test responses of students who were enrolled in a campus-based, postsecondary education program for individuals with developmental disabilities. Random assignment to treatment or control groups and a pre- and posttest design were employed. Students used the six-step ANSWER strategy to analyze essay test prompts, construct outlines, generate essay responses, and revise as needed. The results were evaluated using a strategy scoring rubric. The treatment group received higher scores than the control group in the areas of strategy use and quality of essay responses. The results support the ANSWER strategy as an effective writing intervention for improving students’ essay responses.
Masquerades of Acquired Demyelination in Children
Authors: O’Mahony Julia , Bar-Or Amit , Arnold Douglas L. , Sadovnick A. Dessa , Marrie Ruth Ann , Banwell Brenda ,   Canadian Pediatric Demyelinating Disease Network
Published: May 2012

The diagnosis of acquired demyelinating syndromes of the central nervous system in children requires exclusion of other acute central nervous system disorders. In a 23-site national demyelinating disease study, standardized clinical, laboratory, and magnetic resonance imaging (MRI) data were obtained prospectively from onset, and serially at 3, 6, and 12 months and annually. Twenty of 332 (6%) participants (mean [SD] age, 10.21 [4.32] years; 12 (60%) female) were ultimately diagnosed with vascular disorders (primary or secondary central nervous system vasculitis, vasculopathy, stroke, or migraine, n = 11 children), central nervous system malignancy (n = 3), mitochondrial disease (n = 2), or central nervous system symptoms in the accompaniment of confirmed infection (n = 4). Red flags that may serve to distinguish disorders in the differential of acquired demyelination are described.
The Effect of Hormonal Oral Contraception on Acquisition of Peak Bone Mineral Density of Adolescents and Young Women
Authors: Ziglar Susan , Hunter Tracy S.
Published: May 2012

Maximizing bone mass in youth is touted as the best strategy to offset the natural losses of aging and the menopausal transition. Not achieving maximum peak bone mineral density (BMD) is an independent risk factor for osteoporosis and thus a public health concern. Adolescence is a critical time of bone mineralization mediated by endogenous estradiol. Research has shown that the highest velocity of bone mass accrual occurs 1 year before menarche and after the first 3 years. Low-peak attainment of BMD in young women is associated with contributing factors such as diets low in calcium, eating disorders, lack of exercise, smoking, and low estrogen states. Oral contraceptives (OCs) suppress endogenous estradiol production by suppressing the hypothalamic–pituitary–ovarian axis. Thus, OCs, by replacing endogenous estradiol with ethinyl estradiol (EE), establish and maintain new hormone levels. The early initiation and the use of very low dose of EE raises the possibility that bone mass accrual at a critical time of bone mineralization in young women or adolescents may be jeopardized. This review examines the studies of BMD in adolescents and young women that use combination hormonal contraception. Some studies had inherent limitations, such as small trial, poor control of confounders, failure to exclude women with prior use of hormonal contraceptives, or prior pregnancy from control groups. The vast majority of reviewed studies showed OCs containing 20 to 30 µg of EE interfere with acquisition of peak BMD. Limited numbers of studies examine the effects of OCs containing 35 µg on adolescents and young adults. Additionally, studies are needed evaluating the progestin component of OCs as their differing androgenic properties may affect bone mineralization as well.
Sensor-based motion planning for path tracking and obstacle avoidance of robotic vehicles with nonholonomic constraints
Authors: Kim Dong-Hyung , Han Chang-Soo , Lee Ji Yeong
Published: May 2012

This article presents a sensor-based motion planning method for ro botic vehicles with nonholonomic constraints. With the given waypoints, the instantaneous motion to follow the waypoints is calculated as the turning radius through the geometric path tracking method. By generating the turning radius larger than the minimum turning radius, the motion constraints on the vehicle are satisfied during navigation. And the vehicle is assumed to be equipped with a two-dimensional range sensor, allowing it to avoid obstacles within its sensing range, thus giving it virtual force. Then the turning radius for avoiding an obstacle, which is inversely proportional to the virtual force, is calculated. By integrating the geometric path tracking method and the sensor-based obstacle avoidance method, the vehicle follows the waypoints and avoids unexpected obstacles while it considers the motion constraints. The simulation results of the path tracking only and the path tracking and obstacle avoidance with the given waypoints show the performance of the proposed method.
An investigation of the relationship between hemodynamics and thrombus deposition within patient-specific models of abdominal aortic aneurysm
Authors: O’Rourke Malachy J , McCullough James P , Kelly Sinead
Published: May 2012

The relationship between hemodynamics and thrombus deposition in abdominal aortic aneurysm is investigated for three patients (A, B and C), each with mature fusiform aneurysms. Our methodology utilises initial and follow-up computerised tomography scans for each patient to identify regions of mural thrombus growth and to provide patient-specific models for hemodynamic analysis using computational fluid dynamics. The intervals between scans for patients A, B and C were 17, 15 and 3 months, respectively. The simulations were performed using physiologically realistic boundary conditions. The hemodynamic features of the flow considered include the velocity field, the shear strain rate field, the time averaged wall shear stress and the oscillatory shear index. The parameter that showed best correlation with the location of thrombus growth was the oscillatory shear index. In particular, in the case of patient C where the interval between scans was the shortest, thrombus growth was observed at regions of low oscillatory shear index (OSI < 0.1).
Magnetic resonance imaging-compatible tactile sensing device based on a piezoelectric array
Authors: Hamed Abbi , Masamune Ken , Tse Zion Tsz Ho , Lamperth Michael , Dohi Takeyoshi
Published: May 2012

Minimally invasive surgery is a widely used medical technique, one of the drawbacks of which is the loss of direct sense of touch during the operation. Palpation is the use of fingertips to explore and make fast assessments of tissue morphology. Although technologies are developed to equip minimally invasive surgery tools with haptic feedback capabilities, the majority focus on tissue stiffness profiling and tool–tissue interaction force measurement. For greatly increased diagnostic capability, a magnetic resonance imaging-compatible tactile sensor design is proposed, which allows minimally invasive surgery to be performed under image guidance, combining the strong capability of magnetic resonance imaging soft tissue and intuitive palpation. The sensing unit is based on a piezoelectric sensor methodology, which conforms to the stringent mechanical and electrical design requirements imposed by the magnetic resonance environment. The sensor mechanical design and the device integration to a 0.2 Tesla open magnetic resonance imaging scanner are described, together with the device’s magnetic resonance compatibility testing. Its design limitations and potential future improvements are also discussed. A tactile sensing unit based on a piezoelectric sensor principle is proposed, which is designed for magnetic resonance imaging guided interventions.
The role of biomechanics and engineering in total hip replacement. Why surgeons need technical help
Authors: Jeffers Jonathan RT
Published: May 2012

Implanting the acetabular cup of hard-on-hard bearings, like metal-on-metal or ceramic-on-ceramic, requires considerable surgeon skill to avoid the complications associated with edge loading. Successful cup positioning instruments have been designed in the past by pioneering surgeons, like Peter Ring and Michael Freeman, and these are re-visited in this article. An advantage of these instruments is that they could position the acetabular cup without defining a reference pelvic plane. Computer-assisted cup orientation is able to reduce outliers in cup orientation, but the technology has not been widely adopted. There may be an opportunity to improve the uptake of computer-assisted surgery by incorporating some of the concepts from historically successful manual instruments.
From Coverage to Action
Authors: Merolla Jennifer L. , Pantoja Adrian D. , Cargile Ivy A. M. , Mora Juana
Published: May 2012

The past decade has witnessed a proliferation of media stories about immigration as a result of increases in authorized and unauthorized immigration to the United States. Scholars know little about how this coverage influences political participation across different groups in society. This study employs an experimental design to test the effects of different media frames on immigration in spurring political participation among recent immigrant-rooted communities and non-immigrant-rooted communities. The authors find strong mobilizing effects among Latinos, particularly for frames that highlight social costs and national security concerns, and weak to no effects on Asians, African Americans, and whites.
Long-Run Growth and Welfare Effects of Rising US Public Health Expenditure
Authors: Tobing Elwin , Jeng Jau-Lian
Published: May 2012

The continuing increase of the US public health spending would inevitably lead to a reduction in productive government spending, higher taxes, or both. If the government enacts any of the policies, to what extent would the rising health care spending affect the long-run economic growth and welfare? Using an endogenous growth model where investment in education is the driving force of growth, our quantitative analysis shows that if health is a consumption good, such policies will reduce long-run growth and welfare. To finance public health spending at 20 percent of gross domestic product (GDP), a policy that simultaneously reduces productive government spending and raises tax rates could decrease the long-run growth by 0.7 percentage points and welfare by 14 percent. When health is both consumption and productive good, this policy reduces long-run growth and welfare modestly.
Designing Pareto-Optimal Systems for Complex Selection Decisions
Authors: Druart Celina , De Corte Wilfried
Published: May 2012

The current practice of personnel selection faces the challenge of reconciling the often competing goals of obtaining a high-quality as well as a diverse workforce. To address this challenge for simple selections, De Corte, Sackett, and Lievens (2011) propose using Pareto-optimal predictor composites. These composites yield trade-offs between selection quality and selection diversity levels that cannot be improved simultaneously by any other composite. The current article describes how these Pareto-optimal composites and trade-offs can be developed in complex selection situations, which are characterized by vacancies for at least two different positions and applicants that apply either for one or several of these open positions simultaneously. An analytic method that estimates the selection quality and adverse impact of these complex selection decisions is presented and implemented in a multi-objective optimization program, so as to obtain Pareto-optimal predictor composites. The resulting decision aid is subsequently used to illustrate how it can lead to substantive contributions when considering the quality-diversity dilemma in a complex selection context.
Parametric studies of spur gear lubrication performance considering dynamic loads
Authors: Liu Huaiju , Mao Ken , Zhu Caichao , Xu Xiangyang , Liu Mingyong
Published: May 2012

Effects of friction excitation and gear backlash on spur gear lubrication performance, i.e. minimum film thickness, maximum pressure, etc. are investigated by considering the dynamic loads due to excitations of mesh stiffness, friction between gear tooth, and backlash. Dynamic loads are obtained using a semi-definite two-degree-of-freedom lumped-parameter model. Reduced Reynolds technique is applied to develop a lubrication model capable of dealing with any potential ‘asperity contacts.’ Varying spur gear geometry parameters and the Ree–Eyring fluid behavior are taken into account. Results show that friction excitation has a very limited influence on the dynamic load and hence on the lubrication performance. Backlash affects the dynamic load significantly but has a limited influence on the minimum film thickness. Maximum pressure increases with the value of backlash due to the direct relationship of pressure and load.
Peer group interactions in multilingual educational settings: Co-constructing social order and norms for language use
Authors: Cekaite Asta , Björk-Willén Polly
Published: May 2012

The present study explores peer group interactions in early multilingual educational settings, specifically focusing on children’s language-related episodes. Highlighting the multifaceted work of these interactional practices, it demonstrates in detail how children’s corrective actions, targeting, assessing and criticizing of the other’s language use were utilized in building the peer group identities and relations, while simultaneously indexing local norms for conduct and language use. Designed as outright disagreements with the prior speaker, corrections highlighted the contrast between the recipient’s error and the speaker’s remedy and entailed (a) the disagreement with the prior speaker (e.g. linguistic polarity marker ‘no’), (b) the explicit identification of the trouble source (‘this is not x’) and (c) the instruction as to the correct replacement (‘this is x’). Similarly, word searches in the peer group were resolved so as to index the asymmetry in knowledge between the peers. In the production of corrections, the children displayed and recognized the relevance of appropriate use of the lingua franca (e.g. Swedish) as part of their situated production of local social order. Language expertise was an issue for negotiations and redefinitions in multilingual peer group’s interactions and was one of the factors organizing social relations in multilingual educational settings.
The co-construction of understanding in Danish naturalization interviews
Authors: Fosgerau Christina Fogtmann
Published: May 2012

This article explores excerpts from Danish naturalization interviews. A naturalization interview is a conversation between a Danish police officer and an applicant for Danish citizenship. During the naturalization interview, the police officer decides whether the applicant fulfils a requirement by law. According to the police officers, the language requirement is fulfilled if applicants are able to understand what is said and make themselves understood. The onus is on the applicant to prove that he or she can do just that. However, this article argues that understanding is something that is co-constructed – the police officer is just as involved in the establishment of understanding as is the applicant. By analysing and comparing how different police officers respond to applicants’ answers – how police officers respond in a sequential third position – it is shown that police officers do in fact play a decisive role in the joint understanding established during the naturalization interviews. The naïve notion that it is possible to test applicants’ abilities to understand by involving applicants in so-called natural conversations with police officers is thus disclosed as – naïve.
Bivalved Fiberglass Cast Compared With Plaster Splint Immobilization for Initial Management of Ankle Fracture-Dislocations
Authors: Baker Jeffrey R. , Patel Shail N. , Teichman Adam J. , Bochat Summer E.S. , Fleischer Adam E. , Knight Jessica M.
Published: May 2012

The initial management of ankle fracture-dislocations is the crucial step in the treatment of these emergent traumatic injuries. A stepwise approach is necessary to properly evaluate, diagnose, and treat ankle fracture-dislocations. The goal of initial management is to evaluate the vascular status of the extremity and then restore proper alignment of the talus underneath the tibia. A retrospective review was performed on 40 patients, who presented to a community-based hospital emergency room, treated by the foot and ankle service for ankle fracture-dislocation. An analysis of patient demographics, injury pattern/classification, number of reduction attempts, and immobilization method was performed and evaluated. This analysis was correlated with a review of the literature to develop an algorithm for the initial management of ankle fracture-dislocations recommending the use of a bivalved below-the-knee fiberglass cast for maintained stabilization post reduction.

Level of Evidence: Therapeutic Level IV
Shakespeare and Hobbes
Authors: Dungey Nicholas
Published: May 2012

Thomas Hobbes sought a reconstruction of philosophy, ethics, and politics that would end, once and for all, the bitter disputes that led to the English Civil War. This reconstruction begins with the first principles of matter and motion and extends to a unique account of moral consent and political obligation. However, the author contends that his materialist account of human nature gives rise to a set of perceptions, imaginings, and desires that contribute to the chaos of the state of nature. He argues that the sort of person that emerges from Hobbes’s materialist anthropology is unlikely to be able, or unwilling, to make the necessary agreements about common meaning and language that constitute the ground of the social contract. Following Hobbes’s materialist anthropology, Shakespeare’s Macbeth, and not the rational actor who consents to the social contract, is the more likely result. Performed approximately 25 years before Leviathan appeared, Macbeth provides a literary version of the state of nature, and expresses many of the themes that Hobbes later gave philosophical explanation to. The author suggests that we interpret Macbeth through Hobbes’s materialism. On this reading, the crisis of Macbeth is caused by the material motion of Macbeth’s senses, imagination, and desires. Macbeth provides graphic examples of the type of problems that the author suggests arise from Hobbes’s materialism, and it illuminates the political significance of Macbeth.
Intraclonal heterogeneity and distinct molecular mechanisms characterize the development of t(4;14) and t(11;14) myeloma
Authors: Walker Brian A. , Wardell Christopher P. , Melchor Lorenzo , Hulkki Sanna , Potter Nicola E. , Johnson David C. , Fenwick Kerry , Kozarewa Iwanka , Gonzalez David , Lord Christopher J. , Ashworth Alan , Davies Faith E. , Morgan Gareth J.
Published: May 2012

We have used whole exome sequencing to compare a group of presentation t(4;14) with t(11;14) cases of myeloma to define the mutational landscape. Each case was characterized by a median of 24.5 exonic nonsynonymous single-nucleotide variations, and there was a consistently higher number of mutations in the t(4;14) group, but this number did not reach statistical significance. We show that the transition and transversion rates in the 2 subgroups are similar, suggesting that there was no specific mechanism leading to mutation differentiating the 2 groups. Only 3% of mutations were seen in both groups, and recurrently mutated genes include NRAS, KRAS, BRAF, and DIS3 as well as DNAH5, a member of the axonemal dynein family. The pattern of mutation in each group was distinct, with the t(4;14) group being characterized by deregulation of chromatin organization, actin filament, and microfilament movement. Recurrent RAS pathway mutations identified subclonal heterogeneity at a mutational level in both groups, with mutations being present as either dominant or minor subclones. The presence of subclonal diversity was confirmed at a single-cell level using other tumor-acquired mutations. These results are consistent with a distinct molecular pathogenesis underlying each subgroup and have important impacts on targeted treatment strategies. The Medical Research Council Myeloma IX trial is registered under ISRCTN68454111.
GeVaDSs – decision support system for novel Genetic Vaccine development process
Authors: Blazewicz Jacek , Borowski Marcin , Chaara Wahiba , Kedziora Pawel , Klatzmann David , Lukasiak Piotr , Six Adrien , Wojciechowski Pawel
Published: May 2012

Background

The lack of a uniform way for qualitative and quantitative evaluation of vaccine candidates under development led us to set up a standardized scheme for vaccine efficacy and safety evaluation. We developed and implemented molecular and immunology methods, and designed support tools for immunization data storage and analyses. Such collection can create a unique opportunity for immunologists to analyse data delivered from their laboratories.

Results

We designed and implemented GeVaDSs (Genetic Vaccine Decision Support system) an interactive system for efficient storage, integration, retrieval and representation of data. Moreover, GeVaDSs allows for relevant association and interpretation of data, and thus for knowledge-based generation of testable hypotheses of vaccine responses.

Conclusions

GeVaDSs has been tested by several laboratories in Europe, and proved its usefulness in vaccine analysis. Case study of its application is presented in the additional files. The system is available at:http://gevads.cs.put.poznan.pl/preview/(login: viewer, password: password).
Improving ancient DNA read mapping against modern reference genomes
Authors: Schubert Mikkel , Ginolhac Aurelien , Lindgreen Stinus , Thompson John F , AL-Rasheid Khaled AS , Willerslev Eske , Krogh Anders , Orlando Ludovic
Published: May 2012

Background

Next-Generation Sequencing has revolutionized our approach to ancient DNA (aDNA) research, by providing complete genomic sequences of ancient individuals and extinct species. However, the recovery of genetic material from long-dead organisms is still complicated by a number of issues, including post-mortem DNA damage and high levels of environmental contamination. Together with error profiles specific to the type of sequencing platforms used, these specificities could limit our ability to map sequencing reads against modern reference genomes and therefore limit our ability to identify endogenous ancient reads, reducing the efficiency of shotgun sequencing aDNA.

Results

In this study, we compare different computational methods for improving the accuracy and sensitivity of aDNA sequence identification, based on shotgun sequencing reads recovered from Pleistocene horse extracts using Illumina GAIIx and Helicos Heliscope platforms. We show that the performance of the Burrows Wheeler Aligner (BWA), that has been developed for mapping of undamaged sequencing reads using platforms with low rates of indel-types of sequencing errors, can be employed at acceptable run-times by modifying default parameters in a platform-specific manner. We also examine if trimming likely damaged positions at read ends can increase the recovery of genuine aDNA fragments and if accurate identification of human contamination can be achieved using a strategy previously suggested based on best hit filtering. We show that combining our different mapping and filtering approaches can increase the number of high-quality endogenous hits recovered by up to 33%.

Conclusions

We have shown that Illumina and Helicos sequences recovered from aDNA extracts could not be aligned to modern reference genomes with the same efficiency unless mapping parameters are optimized for the specific types of errors generated by these platforms and by post-mortem DNA damage. Our findings have important implications for future aDNA research, as we define mapping guidelines that improve our ability to identify genuine aDNA sequences, which in turn could improve the genotyping accuracy of ancient specimens. Our framework provides a significant improvement to the standard procedures used for characterizing ancient genomes, which is challenged by contamination and often low amounts of DNA material.