bluuebunny/crossref_metadata_2025 huggingface dataset:
The influence of learner characteristics on degree and type of participation in a CSCL environment
Authors: Prinsen Fleur , Volman Monique L.L. , Terwel Jan
Published: March 2007

Computer‐Supported Collaborative Learning (CSCL) is often presented as a promising learning method. However, it is also facing some new challenges. Apart from answering the question of whether or not working with CSCL generates satisfying learning outcomes, it is important to determine whether or not all participants profit from collaboration, with the computer as a means of communication. This paper describes the implementation and effects of an experimental program in 5 classes with a total of 120 students in elementary education who, in groups of four, engaged in Knowledge Forum discussion tasks on the subject of healthy eating. The study explores whether or not differences occur in the participation of students who differ in gender, sociocultural background and ability, and whether or not computer skills, computer attitudes, comprehensive reading scores and popularity with classmates are related to student participation. Students' participation in this CSCL environment appears to be dependent on a number of learner characteristics. Girls contribute more words to the discussions than boys do and are more dependent on their computer skills in this production. Students who are good at comprehensive reading also contribute more words. Popularity among classmates appears to influence the degree of participation further. We also found indications that students with immigrant parents write fewer contributions than those whose parents are not immigrants.
The quest for deeper learning: an investigation into the impact of a knowledge‐pooling WebQuest in primary initial teacher training
Authors: Allan Jo , Street Mark
Published: March 2007

This paper explores the impact on learning in higher education of the integration of a knowledge‐pooling stage into a WebQuest. We explain the concept of WebQuests, consider recent literature regarding the effects and difficulties of this approach to learning, and examine students' perceptions of the impact of this tool on high‐order learning. The level of learning achieved by respondents is analysed using Biggs' Structure of the Observed Learning Outcomes (SOLO) taxonomy. With judicious use of a ‘pooling knowledge stage’, and provided that students are fully aware of the desired learning outcomes, the findings suggest that WebQuests do have the potential to promote high‐order learning. The paper concludes by suggesting the need for further research into the potential of WebQuests to promote high‐order learning within different disciplines in higher education.
Boardroom Operational and Financial Control: an Insider View*
Authors: Parker Lee D.
Published: March 2007

This study examines the control processes and their dynamics at the board level of two non‐profit organizations with a view to penetrating and exploring directors' control orientations, discourse and decisions in their holistic context. In comparison with the predominantly survey‐ and interview‐based prior research on board‐level control, this study offers a distinctly processual view through its employment of a longitudinal complete member researcher participant observer methodology. Three primary themes of boardroom control focus are identified and analysed. These are control reporting, director's control orientation and the board's budgetary control approach. Directors' strategic orientation is found to be the primary driver of their exercise of control, with reporting systems and routine monitoring emerging as adjuncts to their primary strategic control focus. Strategy‐triggered control activity exhibits itself largely via directors' cost–benefit and risk management analyses communally developed in the course of board meeting exchanges.
Processes of Language Acquisition in Children With Autism: Evidence from Preferential Looking
Authors: Swensen Lauren D. , Kelley Elizabeth , Fein Deborah , Naigles Letitia R.
Published: March 2007

Two language acquisition processes (comprehension preceding production of word order, the noun bias) were examined in 2‐ and 3‐year‐old children (n=10) with autistic spectrum disorder and in typically developing 21‐month‐olds (n=13). Intermodal preferential looking was used to assess comprehension of subject–verb–object word order and the tendency to map novel words onto objects rather than actions. Spontaneous speech samples were also collected. Results demonstrated significant comprehension of word order in both groups well before production. Moreover, children in both groups consistently showed the noun bias. Comprehension preceding production and the noun bias appear to be robust processes of language acquisition, observable in both typical and language‐impaired populations.
A Network Model for Dispersion of Communicable Diseases
Authors: Bian Ling , Liebner David
Published: March 2007

The spread of communicable diseases through a population is an intrinsic spatial and temporal process. This paper presents an individual‐based analytical framework for modeling the spatial and temporal heterogeneity in the disease transmission. The framework specifies a network model structure and six associated parameters. These parameters describe the properties of nodes, the properties of links, and the topology of the network. Through this model structure and associated parameters, this framework allows the representation of discrete individuals, individualized interactions, and interaction patterns in a network of human contact. The explicit representation of the spatial distribution and mobility of individuals in particular facilitates the modeling of spatial heterogeneity in the disease transmission.
An Investigation into the Causes of Errors and Inconsistencies in Predicted Viewsheds
Authors: Riggs Philip D , Dean Denis J
Published: March 2007

Previous evaluations of viewshed analyses have raised concerns about the accuracy and repeatability of the process. Digital elevation model (DEM) errors, the limited spatial resolution of DEMs, and differing algorithms employed by different GIS packages have all been suggested as possible sources for inaccuracy and non‐repeatability. This study compared a field surveyed viewshed to predicted viewsheds generated using a variety of software packages and DEM databases, some of which contained known amounts of error. We found that each of the factors suggested by previous authors contributes to errors in predicted viewsheds. DEM errors contribute most to the discrepancies between surveyed and predicted viewsheds, and the majority of their negative impact occurred at very low levels of DEM error. Differing algorithms used by different GIS packages also contribute significantly to surveyed/predicted viewshed discrepancies, but more importantly, result in predicted viewsheds that disagree with one other, thereby confounding comparisons of results generated with differing software systems. Finally, the spatial resolution of DEMs also has a significant effect on the degree of agreement between surveyed and predicted viewsheds, but the magnitude of this effect is not as great as are the effects produced by DEM errors.
COMPARATIVE THEOLOGY AFTER LIBERALISM
Authors: NICHOLSON HUGH
Published: March 2007

This article first identifies two reasons for the current marginality of the theological sub‐discipline of “comparative theology.” The first is an awareness of the imperialistic character of the universalist (inclusivist and pluralist) theologies of the recent past. The second is the assumption that Christianity's relations with other religious are extrinsic to Christian identity. Drawing on Kathryn Tanner's critique of postliberalism, it argues that interreligious comparison is integral to a theology that recognizes the essentially relational nature of Christian identity. This recognition implies a continuous revision of Christian identity that checks the tendency to essentialize and thereby exclude religious “others.”
Combining Work as an Historian and Activist: A Personal Account1
Authors: Wittner Lawrence S.
Published: March 2007

This essay examines how I have blended my roles as an activist and as a historian. Over the years, I have participated in the peace, racial justice, and labor movements, and this activism has significantly affected both my scholarship and teaching. It has also complicated my professional life in a number of ways—absorbing time and energy that might have been devoted to additional scholarship, limiting fellowship opportunities, and (at least initially) blocking my receipt of tenure. Overall, however, I have found the combination of activism and historical work very satisfying, for it has contributed to humane causes and provided me with an interesting and meaningful life.
“An International Alliance of People of All Nations Against Racism”: Nonviolence and Solidarity in the Antiapartheid Activism of the American Committee on Africa, 1952–19651
Authors: Hostetter David
Published: March 2007

Martin Luther King's 1965 call for “People of all Nations” to impose economic sanctions on South Africa grew from his experience with active nonviolence in the American civil rights movement. King worked with the American Committee on Africa (ACOA) to oppose apartheid. Initially, both ACOA and King looked to the antiapartheid struggle in South Africa as an exemplary use of nonviolence in opposition to racial segregation. The 1960 Sharpeville Massacre, which prompted the South African antiapartheid movement's turn from nonviolence to armed struggle, created a quandary for American advocates of nonviolence. King and ACOA responded to this dilemma by advocating the transnational application of sanction and boycott. Thus, a new form of solidarity developed in which opponents of apartheid outside South Africa used nonviolence to help create ways for peoples of all nations to express their opposition to racism.
Planning for Peace: Virginia Gildersleeve at the United Nations Conference on International Organization
Authors: Snider Christy Jo
Published: March 2007

Virginia Gildersleeve, the Dean of Barnard College and the former president of the International Federation of University Women, served as the only U.S. woman delegate to the conference that established the United Nations in 1945. President Franklin Roosevelt selected Gildersleeve to attend the conference to placate those women's groups advocating that their gender participate in postwar peace planning. She was chosen over other women, however, primarily due to her interwar leadership of a gender‐specific transnational nongovernmental organization. Male delegates to diplomatic conferences typically gained their international experience as politicians, State Department officials, or military officers. Women, who had not made significant inroads into foreign policy decision‐making positions after gaining the right to vote, had to attain their diplomatic skills elsewhere. Leadership roles in transnational women's organizations became a springboard for women like Gildersleeve into professional diplomacy.
The“Good War”and Baptists Who Refused to Fight It
Authors: Dekar Paul R.
Published: March 2007

This article explores the legacy of some of four hundred Baptists who refused combatant duty during World War II, characterized by some as the quintessential “good war.” Drawing on research concerning the motivation of several conscientious objectors, their role during the war and their postwar activity, this article complements a recent documentary film, The “Good War” and Those Who Refused to Fight It, which highlights the impact of their war resistance on conscientious objectors who subsequently fueled such social movements as the campaign to control the spread of nuclear weapons, to protect the environment, and to champion civil rights in the United States.
Globalization, Human Resource Practices and Innovation: Recent Evidence from the Canadian Workplace and Employee Survey
Authors: WALSWORTH SCOTT , VERMA ANIL
Published: March 2007

This study examines the triangular relationship that connects the degree to which a workplace is internationally engaged, the extent to which it innovates, and the human resource practices it adopts. By pooling various years of data from the Canadian Workplace and Employee Survey, a nationally representative data set, we found that certain practices, such as variable pay and autonomy training, are more likely to be used in international workplaces. We subsequently found that for an international workplace, the use of variable pay contributes very little to workplace innovation while autonomy training has a positive relationship with innovation.
Integrating Human Resource and Technological Capabilities: The Influence of Global Business Strategies on Workplace Strategy Choices
Authors: COOKE WILLIAM N.
Published: March 2007

Treating workplace strategies as the integration of human resource and technological capabilities, a typology of workplace strategy emphases is developed. The choice among these alternative workplace strategy emphases is treated as a function of market‐positioning priorities and the multinational scope of firms. Accordingly, a multinomial choice model is specified, which is tested against a sample of firms in the U.S. automotive supplier industry. The model obtains substantial empirical support. Among the findings is evidence consistent with the proposition that due to cross‐border, isomorphic constraints, multinational companies are less likely than national companies to pursue workplace strategies emphasizing human resource capabilities, choosing instead to favor the diffusion of workplace strategies emphasizing technological capabilities.
Globalization and Declining Unionization in the United States
Authors: SLAUGHTER MATTHEW J.
Published: March 2007

For decades, the private‐sector unionization rate in the United States has been falling. At the same time, the integration of the United States into the world economy has been rising. Many anecdotes suggest the latter has played a role in that decline, with unions feeling pressured to reduce employment and/or compensation demands in the face of rising cross‐border activity of employers. To investigate this possibility econometrically, in this paper I assembled a panel of U.S. manufacturing industries that matches union‐coverage rates with measures of global engagement such as exports, imports, tariffs, transportation costs, and foreign direct investment. The main finding is a statistically and economically significant correlation between falling union coverage and greater numbers of inward FDI transactions. Possible interpretations of this finding are then discussed. Because U.S. affiliates of foreign multinationals have higher unionization rates than U.S.‐based firms do, this correlation does not reflect just a compositional shift toward these affiliates. Instead, it may reflect pressure of international capital mobility on U.S.‐based companies, consistent with research on how rising capital mobility raises labor‐demand elasticities and alters bargaining power.
U.S. Multinational Activity Abroad and U.S. Jobs: Substitutes or Complements?
Authors: HARRISON ANN E. , MCMILLAN MARGARET S. , NULL CLAIR
Published: March 2007

Critics of globalization claim that firms are being driven by the prospects of cheaper labor and lower labor standards to shift employment abroad. Yet the evidence, beyond anecdotes, is slim. This paper reports stylized facts on the activities of U.S. multinationals at home and abroad for the years 1977 to 1999. We focus on firms in manufacturing and services, two sectors that have received extensive media attention for supposedly exporting jobs. Using firm‐level data collected by the Bureau of Economic Analysis (BEA) in Washington, D.C., we report correlations between U.S. multinational employment at home and abroad. Preliminary evidence based on the operations of these multinationals suggests that the sign of the correlation depends on the crucial distinction between affiliates in high‐income and low‐income countries. For affiliates in high‐income countries there is a positive correlation between jobs at home and abroad, suggesting that foreign employment of U.S. multinationals is complementary to domestic employment. For firms that operate in developing countries, employment has been cut in the United States, and affiliate employment has increased. To account for firm size, substitution across firms and entry and exit, we aggregate our data to the industry level. This exercise reveals that the observed “complementarity” between U.S. and foreign jobs has been driven largely by a contraction across all manufacturing sectors. It also reveals that foreign employment in developing countries has substituted for U.S. employment in several highly visible industries, including computers, electronics, and transportation. The fact that there were U.S. jobs lost to foreign affiliates in key sectors, despite broad complementarity in hiring and firing decisions between U.S. parents and their affiliates, helps explain why economists view the impact of globalization on U.S. jobs as benign despite negative news coverage for declining industries.
Enforcing Labor Rights against Multinational Corporate Groups in Europe
Authors: KRYVOI YARASLAU
Published: March 2007

Voluntary corporate codes of conduct for multinational enterprises can have certain quasi‐legal effects for national legal systems, but the enforcement of labor standards remains at the national level. Two main obstacles to the enforcement of labor rights against multinationals are limited access to justice in multinationals’ home countries and the concept of limited liability. These obstacles are understood differently in common law and civil law jurisdictions and require different approaches to overcome them.
Morphology, locomotor behaviour and microhabitat use in North American squirrels
Authors: Essner R. L.
Published: March 2007

The rodent family Sciuridae (squirrels) presents an ideal system for examining the morphological, behavioural and ecological correlates of locomotor novelty. Ancestrally, sciurids were arboreal, a condition retained by modern tree squirrels. Two major transitions from the arboreal condition are hypothesized to have occurred in the sciurid clade: (1) flying squirrels evolved gliding from arboreal leaping (parachuting) and (2) chipmunks and ground squirrels became semiarboreal/terrestrial. This study examines morphology, locomotor behaviour and microhabitat use under controlled laboratory conditions in three North American sciurids: eastern chipmunkTamias striatus, red squirrelTamiasciurus hudsonicusand southern flying squirrelGlaucomys volans. Multivariate space was defined using a series of morphological measurements and by continuously sampling individuals moving under identical conditions in a naturalistic enclosure, controlling for the proximate effects of microhabitat structure. Morphospace was characterized by a contrast between proximal and distal limb elements – flying squirrels exhibited elongated forelimbs and shanks and shortened forefeet and hindfeet, while chipmunks exhibited the opposite pattern. Ethospace was characterized by a contrast between aerial locomotion in flying squirrels and ground‐based locomotion in chipmunks. In both instances, red squirrels occupied intermediate positions, as predicted on the basis of retention of ancestral features. Despite significant differences among species at morphological and behavioural levels, ecospace was characterized by overlap between flying squirrels and red squirrels in the use of high supports, and between flying squirrels and chipmunks in the use of large‐diameter supports. The lack of concordance at the ecological level underscores the difficulty in making predictions based solely upon organismal design.
Changing the national past: re‐creating the democratic Polish nation after 1989
Authors: KAFTAN JOANNA
Published: March 2007

ABSTRACT. Poland provides a critical example for studying how national identity is transformed to fit new domestic and global circumstances. While Poles must re‐identify themselves as a democratic nation, they have a choice of whether to incorporate aspects of the communist experience or to ignore it and draw solely from other historical sources. A comparison of holiday newspaper articles from before and after 1989 provides an opportunity to observe this process through the lens of national commemoration. This review shows that themes of national identity are influenced by political context and their potential to unify without contestation. In addition, while the communist period remained a salient unifying historical experience for Poles, democratic values did not act as a unifying theme during the first ten years of Polish democracy.
The effects of running, environment, and attentional focus on athletes’ catecholamine and cortisol levels and mood
Authors: HARTE JANE L. , EIFERT GEORG H.
Published: March 2007

This study was designed to examine some of the psychoneuroendocrine effects of exercise‐induced emotional experiences and the mediating effects of environmental setting and subjects’ attentional focus. Trained runners were tested during an outdoor run and two indoor treadmill running conditions. Excretions of catecholamines and Cortisol significantly increased after all running conditions but not after a control condition. Results indicate that patterns of endocrine and concomitant emotional change through exercise differ when environmental setting and attentional focus are altered in such a way that a normally pleasant task such as running becomes tedious and negatively evaluated. These findings support the notion that setting, attention, and cognitive appraisal may alter the emotional experience associated with physical exercise.
Startle potentiation during anticipation of a noxious stimulus: Active versus passive response sets
Authors: PATRICK CHRISTOPHER J. , BERTHOT BRYAN D.
Published: March 2007

The startle reflex response increases during aversive stimulus processing. This study examined whether differing response sets affected startle potentiation during anticipation of an aversive event. Two groups received a noxious noise blast following a 6‐s warning cue. Subjects in the active group could press a switch to stop the noise; yoked passive subjects received the same noises with no control. Subjects in a yoked control group heard a soft tone following cue offset. Acoustic startle probes were presented during some of the warning periods and during some of the intertrial intervals. The major finding was that the active and passive groups did not differ in startle potentiation. In comparison with controls, startle reactions for both groups were larger and faster during the warning cue than between trials. The results suggest that the startle reflex indexes defensive response mobilization independently of specific task demands.
RISK, MEDICINE AND WOMEN: A CASE STUDY ON PRENATAL GENETIC COUNSELLING IN BRAZIL
Authors: GUILAM MARIA CRISTINA R. , CORRÊA MARILENA C.D.V.
Published: March 2007

Genetic counselling is an important aspect of prenatal care in many developed countries. This tendency has also begun to emerge in Brazil, although few medical centres offer this service. Genetic counselling provides prenatal risk control through a process of individual decision‐making based on medical information, in a context where diagnostic and therapeutic possibilities overlap. Detection of severe foetal anomalies can lead to a decision involving possible termination of pregnancy. This paper focuses on medical and legal consequences of the detection of severe foetal anomalies, mainly anencephaly and Down syndrome, and in light of the fact that abortion is illegal in Brazil. The discussion is based on the literature and empirical research at a high‐complexity public hospital in Rio de Janeiro.
Phosphorus balances for arable soils in Southern England 1986–1999
Authors: Heming S. D.
Published: March 2007

The behaviour of P in a range of English arable soils was examined by plotting the change in resin P in the topsoil (ΔPres) at the end of a 3‐ to 5‐year period, against the P balance over the same period (fertilizer P applied minus offtake in crops, estimated from farmers’ reported yields and straw removal). Based on the assumption that values for offtake per tonne of crop yield used for UK arable crops are valid averages, 20–60% of ΔPres was explained by the balance. Applying excess P fertilizer increased Pres, and reducing P fertilizer use decreased it; typically 3–4 kg P ha−1 was required for each mg L−1ΔPres (6–8 kg ha−1 for each mg L−1 of Olsen P). About half the P balance seems to be resin extractable and this differed little between soil groups, except in cases of very low P (index 0) in which the P buffering was stronger, and on very high P soils (index 4/5) when buffering was less. However, on calcareous soils and red soils, when fertilizer was applied in accord with offtake, Pres fell by up to 4 mg L−1 year−1 (2 mg L−1 yr−1 olsen P) and to prevent this an extra 3–10 kg P ha−1 year−1 fertilizer was required. But on most non‐calcareous soils, replacing offtake maintained Pres, with perhaps slight rises on soils of low clay content or greater organic matter content. In soils under arable rotations, the apparent recovery of P from fertilizer was often around 100%, falling to 85% on Chalk soils and 75% on medium–heavy soils on limestone or Lower Chalk. The fate of the ‘missing’ P needs clarification. The case for corrections to current P fertilizer recommendations in the UK on certain soil types is discussed.
Impact of grazed grassland management on total N accumulation in soil receiving different levels of N inputs
Authors: Watson C. J. , Jordan C. , Kilpatrick D. , McCarney B. , Stewart R.
Published: March 2007

Nitrogen balances and total N and C accumulation in soil were studied in reseeded grazed grassland swards receiving different fertilizer N inputs (100–500 kg N ha−1 year−1) from March 1989 to February 1999, at an experimental site in Northern Ireland. Soil N and C accumulated linearly at rates of 102–152 kg N ha−1 year−1 and 1125–1454 kg C ha−1 year−1, respectively, in the top 15 cm soil during the 10 year period. Fertilizer N had a highly significant effect on the rate of N and C accumulation. In the sward receiving 500 kg fertilizer N ha−1 year−1 the input (wet deposition + fertilizer N applied) minus output (drainflow + animal product) averaged 417 kg N ha−1 year−1. Total N accumulation in the top 15 cm of soil was 152 kg N ha−1 year−1. The predicted range in NH3 emission from this sward was 36–95 kg N ha−1 year−1. Evidence suggested that the remaining large imbalance was either caused by denitrification and/or other unknown loss processes. In the sward receiving 100 kg fertilizer N ha−1 year−1, it was apparent that N accumulation in the top 15 cm soil was greater than the input minus output balance, even before allowing for gaseous emissions. This suggested that there was an additional input source, possibly resulting from a redistribution of N from lower down the soil profile. This is an important factor to take into account in constructing N balances, as not all the N accumulating in the top 15 cm soil may be directly caused by N input. N redistribution within the soil profile would exacerbate the N deficit in budget studies.
Pushing boundaries in paediatric intensive care: training as a paediatric retrieval nurse practitioner
Authors: Davies Jo , Lynch Fiona
Published: March 2007

Traditionally in the UK, the transportation of the critically ill child to a paediatric intensive care unit has been carried out by a medically led team of doctors and nurses. However, in countries such as the USA and Canada, appropriately trained nurse practitioners have proven to be competent in the transportation of these vulnerable children. This nurse‐led team model has also been shown to be successful in the speciality of neonatal care in the UK. The impact of changes in the National Health Service (NHS) has led to an increased demand for the transportation of the child requiring paediatric intensive or high‐dependency care, the lifting of restrictions on nursing practice and the reduction of doctors’ hours in keeping with the European Working Time Directive. This has led to one NHS Trust in the UK developing the role of paediatric retrieval nurse practitioners (RNP): nurses who lead the retrieval team. The purpose of this article is to describe a pilot initiative to develop the role of RNPs. The comprehensive process of recruitment, training and assessment of competency will be detailed. Personal reflection on the project will also explore the pertinent nursing issues around; role impact and definition, conflict and change management, communication, legislation and personal and professional growth. Recommendations for future initiatives will also be explored.
An audit of ward nurses’ knowledge of sepsis
Authors: Robson Wayne , Beavis Sarah , Spittle Nick
Published: March 2007

Many of the patients with sepsis admitted to intensive care and high dependency units develop severe sepsis/septic shock in general hospital wards. If the Surviving Sepsis Campaign’s aim of a 25% reduction in mortality from sepsis is to be achieved by 2009, then it is essential that registered nurses are aware of the standard definitions of sepsis, and the recommendations for its initial management. The aim of this study was to audit ward nurses’ knowledge of sepsis against standard definitions and evidence‐based management guidelines. An audit was carried out in one acute hospital to assess ward nurses’ knowledge of sepsis. Seventy‐three registered nurses from medical, surgical and orthopaedic wards completed a questionnaire about the signs and symptoms of sepsis and its initial management. The results showed that some ward nurses appeared to have a poor knowledge of the signs and symptoms of sepsis, severe sepsis/septic shock and some aspects of its initial management. Following the results of the audit, a variety of educational initiatives were introduced to raise awareness of the standard definitions and the surviving sepsis management guidelines. In conclusion, targeted education must be provided for nurses working in general wards if the Surviving Sepsis Campaign is to achieve its aim of a 25% reduction in mortality by 2009.
Utility of the Myocardial Performance Index in a Population with High Prevalences of Obesity, Diabetes, and Hypertension: The Strong Heart Study
Authors: Mishra Rakesh K. , Kizer Jorge R. , Palmieri Vittorio , Roman Mary J. , Galloway James M. , Fabsitz Richard R. , Lee Elisa T. , Best Lyle G. , Devereux Richard B.
Published: March 2007

Introduction: The myocardial performance index (MPI) introduced by Tei, a Doppler‐derived echocardiographic measure that reflects both left ventricular (LV) systolic and diastolic function, has been shown to have prognostic value in several clinical settings, including myocardial infarction and congestive heart failure. There are scant data on the correlates and prognostic value of MPI in a population without overt cardiovascular (CV) disease. Methods: We investigated clinical and physiologic correlates of MPI, as assessed from echocardiographic Doppler recordings in 1,862 American Indian participants free of coronary or valvular disease or LV systolic dysfunction in the population‐based strong heart study (SHS). We then assessed the prognostic value of MPI for incident CV events, including nonfatal stroke, coronary heart disease, congestive heart failure, and CV death. Results: The study population was 59 ± 8 years old (66% women); 48% had diabetes, 44% hypertension, and 54% were obese. In univariable analyses, MPI (mean = 0.24 ± 0.17) showed significant negative associations with creatinine clearance, C‐reactive protein (CRP), LV ejection fraction (EF), mitral valve E‐ and A‐wave velocities, cardiac index (CI), stroke index (SI) and stroke index/pulse pressure (SI/PP), and significant positive associations with serum creatinine and total peripheral resistance index (TPRI) (all P < 0.05). There were no significant associations of MPI with hypertension or diabetes status, systolic or diastolic blood pressure, body mass index, hemoglobin A1C or LV mass. After adjusting for age, sex, diabetes, and hypertension, MPI remained weakly but significantly correlated with CRP, EF, CI, SI, SI/PP, mitral E‐ and A‐wave velocities, and TPRI. MPI did not predict fatal and nonfatal CV events (risk ratio 1.06 per unit MPI, 95% C.I. 0.56–2.04; P = 0.85) at a mean follow‐up of 7.1 ± 2.2 years. Conclusions: In a population‐based sample of adults with high prevalence of diabetes, hypertension, and obesity but without overt CV disease, MPI has weak associations with clinical and physiologic determinants of cardiac function. Moreover, MPI does not provide prognostic information for CV events in this population. Though conceptually attractive as a global measure of cardiac function, MPI has limited utility in a high‐risk population without clinical CV disease.
Validation of the Peak to Mean Pressure Decrease Ratio as a New Method of Assessing Aortic Stenosis Using the Gorlin Formula and the Cardiovascular Magnetic Resonance‐Based Hybrid Method
Authors: Haghi Dariusch , Kaden Jens J. , Suselbeck Tim , Fluechter Stephan , Breithardt Ole A , Poerner Tudor , Kalmar Gabor , Borggrefe Martin , Papavassiliu Theano
Published: March 2007

Background: We sought to validate the recently introduced peak to mean pressure decrease ratio (PMPDR), using the Gorlin formula and a hybrid method which combines cardiovascular magnetic resonance (CMR)‐derived stroke volume with transaortic Doppler measurements to calculate aortic valve area (AVA). Methods: Data analysis in 32 patients with severe (AVA <= 0.75 cm2) or moderate aortic stenosis who had prospectively been entered into our aortic stenosis database. Results: Gorlin‐derived AVA was 0.61 ± 0.10 cm2 in severe and 0.92 ± 0.14 cm2 in moderate aortic stenosis (P < 0.01). Corresponding values for PMPRD were 1.61 ± 0.10 and 1.73 ± 0.18, respectively (P < 0.05). Sensitivity, specificity, positive and negative predictive values for PMPDR <1.5 to predict severe aortic stenosis were 0.12, 0.92, 0.67, and 0.44 as assessed by the Gorlin formula. Conclusions: Using the Gorlin formula as the reference standard, our study confirms results of a previously reported study on the performance of PMPDR for assessment of aortic stenosis.
The Impact of Hypertension and Hypertension‐Related Left Ventricle Hypertrophy on Right Ventricle Function
Authors: Tumuklu M. Murat , Erkorkmaz Unal , Öcal Arslan
Published: March 2007

Aim: The aim of our study is to determine the effect of hypertension and hypertension‐related left ventricle hypertrophy on right ventricle (RV) morphology and function by using RV standard Doppler echocardiographic indices, myocardial Doppler imaging, and strain/strain rate imaging indices. Methods: We studied 35 patients with arterial hypertension and 30 age‐ and sex‐adjusted control subjects who had no other pathological conditions. Standard transthoracic Doppler echocardiographical measurements, pulsed‐wave tissue Doppler from tricuspid anulus (Peak systolic‐st, peak early diastolic‐et, peak late diastolic velocity‐at), reconstructed spectral pulsed‐wave tissue Doppler velocities (peak systolic‐S, peak early‐E, peak late diastolic velocity‐A), and strain/strain rate imaging of RV free wall mid region (peak systolic strain‐∈, peak systolic strain rate‐SR) were obtained. Results: Age, body surface area, blood pressure, and heart rate were comparable between two groups. Hypertensive subjects had significantly increased LV end‐diastolic septal and posterior wall thickness, left atrial diameter, LV mass, LV mass index, and relative wall thickness during diastole. At the level of right ventricular lateral tricuspid annulus without systolic changes, the majority of diastolic measurements were altered in hypertensives (early diastolic velocity et; 13 ± 2 vs. 18 ± 4 m/sec, P < 0.0001, late diastolic velocity at; 20 ± 4 vs. 14 ± 3 m/sec, P < 0.0001, early to late diastolic velocity ratio; 0.69 ± 0.14 vs. 1.32 ± 0.38, P < 0.0001). The velocity data from two‐dimensional color myocardial imaging at the level of RV free wall mid region again showed altered diastolic measurements in hypertensives (E; 8.01 ± 2.6 vs. 10.4 ± 3.14 m/sec, P < 0.001, A; 11.5 ± 2.6 vs. 9.12 ± 3.7 m/sec, P < 0.0001, E/A ratio; 0.75 ± 0.41 vs. 1.87 ± 0.48, P < 0.00). The peak systolic strain of RV free wall mid region was significantly lower in hypertensive individuals than controls (25.666 ± 5.64 vs. 30.03 ± 6.78%, P < 0.05). No significant differences were found in other parameters of RV function between hypertensive and control subjects. Conclusions: The present study demontrates that besides the manifest morphologic LV adaptations, significant RV functional alterations can be determined by TDI and strain/strain rate imaging in patients arterial hypertension. Both tissue velocities by TDI and strain imaging may be new tools to define and quantitate subtle change in systolic and diastolic function of right ventricular function in arterial hypertension that cannot be determined in standard echocardiographic parameters.
Life history and host‐plant relationships of the rare endemic Arctic aphid Acyrthosiphon calvulus in a changing environment
Authors: Gillespie Mark , Hodkinson Ian D. , Cooper Elisabeth J. , Bird Jeremy M. , Jónsdóttir Ingibjörg S.
Published: March 2007

This article examines the abundance, life history, host‐plant relationships, and overwintering biology of Acyrthosiphon calvulus Ossiannilsson (Homoptera: Aphididae) as a precursor to understanding its rarity and potential response to a changing climate. Acyrthosiphon calvulus is restricted to a few scattered localities on the west coast of Spitsbergen, Svalbard, Norway, where it reproduces on Salix polaris WG (Salicaceae) and its taxonomically unrelated root parasite Pedicularis hirsuta L. (Scrophulariaceae). Acyrthosiphon calvulus overwinters as eggs. Hatching fundatrices give rise directly to males and oviparae, which mate and lay overwintering eggs. The life cycle is closely synchronized with the phenology of S. polaris and appears genetically programmed, lacking summer generations of viviparae. Alate forms are similarly unknown. The progeny sequence of fundatrices resulted in a sex ratio for the sexuales that is strongly female biased (3:1). Eggs hatch coincided with budburst in early June and fundatrices developed on the expanding leaves. Egg production by oviparae corresponded with leaf senescence in July and August. Overwintering egg survival was high, with supercooling points ranging from −29 to −40 °C, lower than the extreme winter minimum temperature recorded (−28 °C). Egg development and hatching occurred at or below 5 °C and sub‐zero temperatures were not required to break diapause. The scarcity and fragmented distribution of A. calvulus is discussed in the context of the ubiquity of its host plants on Spitsbergen.
A possible role of thymidine phosphorylase expression and5‐fluorouracil increased sensitivity in oropharyngeal cancer patients
Authors: Ranieri G. , Grammatica L. , Patruno R. , Zito A.F. , Valerio P. , Iacobellis S. , Gadaleta C. , Gasparini G. , Ribatti D.
Published: March 2007

Thymidine Pi deoxyribosyltransferase (TP) is an enzyme involved in DNA synthesis up‐regulated in tumours and it is also a pro‐angiogenic factor. TP cannot activate capecitabine, because capecitabine first needs conversion by carboxylesterase and cytidine deaminase into 5‐deoxy‐fluorouridine. This compound can be activated by TP to 5‐fluorouracil (5‐FU). Although TP is not necessary for 5‐FU toxicity, experimental data suggest that high levels of TP correlate with an enhanced response to 5‐FU therapy. In this study, we have analysed by immunohistochemistry CD34, CD68 and TP positive cells in bioptic samples from 53 patients with T1–3 N0–1 M0 oropharyngeal squamous cell carcinoma (OSC) and from 24 patients with non‐dysplastic oropharyngeal leukoplakia (NDOLP). Results showed that the mean of TP‐positive cells, CD68 positive macrophages and CD34 positive endothelial cells eval‐uated as microvessel density (MVD) was significantly higher in OSC than in NDOLP. Moreover, at a median follow‐up of 19 months, patients with TP expression and higher MVD showed a better survival rate as compared to those with low MVD, probably as a consequence of 5‐FU‐based therapy.We hypothesized a role for TP in oropharyngeal tumourigenesis and 5‐FU activation in the adjuvant setting of OSC patients.
Altered brain‐derived neurotrophic factor blood levels and gene variability are associated with anorexia and bulimia
Authors: Mercader J. M. , Ribasés M. , Gratacòs M. , González J. R. , Bayés M. , De Cid R. , Badía A. , Fernández‐Aranda F. , Estivill X.
Published: March 2007

Murine models and association studies in eating disorder (ED) patients have shown a role for the brain‐derived neurotrophic factor (BDNF) in eating behavior. Some studies have shown association of BDNF −270C/T single‐nucleotide polymorphism (SNP) with bulimia nervosa (BN), while BDNF Val66Met variant has been shown to be associated with both BN and anorexia nervosa (AN). To further test the role of this neurotrophin in humans, we screened 36 SNPs in the BDNF gene and tested for their association with ED and plasma BDNF levels as a quantitative trait. We performed a family‐based association study in 106 ED nuclear families and analyzed BDNF blood levels in 110 ED patients and in 50 sib pairs discordant for ED. The rs7124442T/rs11030102C/rs11030119G haplotype was found associated with high BDNF levels (mean BDNF TCG haplotype carriers = 43.6 ng/ml vs. mean others 23.0 ng/ml, P = 0.016) and BN (Z = 2.64; P recessive = 0.008), and the rs7934165A/270T haplotype was associated with AN (Z =−2.64; P additive = 0.008). The comparison of BDNF levels in 50 ED discordant sib pairs showed elevated plasma BDNF levels for the ED group (mean controls = 41.0 vs. mean ED = 52.7; P = 0.004). Our data strongly suggest that altered BDNF levels modulated by BDNF gene variability are associated with the susceptibility to ED, providing physiological evidence that BDNF plays a role in the development of AN and BN, and strongly arguing for its involvement in eating behavior and body weight regulation.
Forward genetic screen of mouse reveals dominant missense mutation in the P/Q‐type voltage‐dependent calcium channel, CACNA1A
Authors: Xie G. , Clapcote S. J. , Nieman B. J. , Tallerico T. , Huang Y. , Vukobradovic I. , Cordes S. P. , Osborne L. R. , Rossant J. , Sled J. G. , Henderson J. T. , Roder J. C.
Published: March 2007

Dominant mutations of the P/Q‐type Ca2+ channel (CACNA1A) underlie several human neurological disorders, including episodic ataxia type 2, familial hemiplegic migraine 1 (FHM1) and spinocerebellar ataxia 6, but have not been found previously in the mouse. Here we report the first dominant ataxic mouse model of Cacna1a mutation. This Wobbly mutant allele of Cacna1a was identified in an ethylnitrosourea (ENU) mutagenesis dominant behavioral screen. Heterozygotes exhibit ataxia from 3 weeks of age and have a normal life span. Homozygotes have a righting reflex defect from postnatal day 8 and later develop severe ataxia and die prematurely. Both heterozygotes and homozygotes exhibit cerebellar atrophy with focal reduction of the molecular layer. No obvious loss of Purkinje cells or decrease in size of the granule cell layer was observed. Real‐time polymerase chain reaction revealed altered expression levels of Cacna1g, Calb2 and Th in Wobbly cerebella, but Cacna1a messenger RNA and protein levels were unchanged. Positional cloning revealed that Wobbly mice have a missense mutation leading to an arginine to leucine (R1255L) substitution, resulting in neutralization of a positively charged amino acid in repeat III of voltage sensor segment S4. The dominance of the Wobbly mutation more closely resembles patterns of CACNA1A mutation in humans than previously described mouse recessive mutants (tottering, leaner, rolling Nagoya and rocker). Positive‐charge neutralization in S4 has also been shown to underlie several cases of human dominant FHM1 with ataxia. The Wobbly mutant thus highlights the importance of the voltage sensor and provides a starting point to unravel the neuropathological mechanisms of this disease.
A polymorphism in SOD2 is associated with development of Alzheimer’s disease
Authors: Wiener H. W. , Perry R. T. , Chen Z. , Harrell L. E. , Go R. C. P.
Published: March 2007

Genes involved in cellular mechanisms to repair oxidative damage are strong candidates as etiologic factors for Alzheimer’s disease (AD). One important enzyme involved in this mechanism is superoxide dismutase 2 (SOD2). The gene for this enzyme lies within a single haplotype block at 6q25.3, a region showing evidence for linkage to AD in a genome scan. We genotyped four single nucleotide polymorphisms (SNPs) in SOD2 in families of the National Institute of Mental Health‐AD Genetics Initiative (ADGI): rs2758346 in the 5′ untranslated region (UTR), rs4880 in exon 2, rs2855116 in intron 3 and rs5746136 in the 3′UTR. Under a dominant model, family‐based association tests showed significant evidence for association of AD with the first three loci in a candidate gene set of families with individuals having age of onset of at least 50 years and two affected and one unaffected sibling, and in a late‐onset subset of families (families with all affected individuals having age of onset of at least 65 years) from the full ADGI sample. The alleles transmitted more frequently to cases than expected under the null hypothesis were T, C, G, and G. Global tests of the transmission of haplotypes indicate that the first two loci have the most consistent association with risk of AD. Because of the high linkage disequilibrium in this small (14 kb) gene, and the presence of 100 SNPs in this gene, 26 of which may have functional significance, additional genotyping and sequencing are needed to identify the functionally relevant SNP. We discuss the importance of our findings and the relevance of SOD2 to AD risk.
The CRHR1 gene: a marker for suicidality in depressed males exposed to low stress
Authors: Wasserman D. , Sokolowski M. , Rozanov V. , Wasserman J.
Published: March 2007

The risk of suicide, which causes about 1 million deaths each year, is considered to augment as the levels of stress increases. Dysregulation in the stress response of the hypothalamic‐pituitary‐adrenocortical (HPA) axis, involving the corticotrophin‐releasing hormone (CRH) and its main receptor (CRHR1), is associated with depression, frequent among suicidal males. Here we have analyzed single nucleotide polymorphisms (SNPs) in these genes, in family trios with suicide attempter offspring (n = 542), by using the transmission disequilibrium test both in a two‐staged screening/replication sample design and in detailed reanalysis in the entire sample. Stratification based on the levels of lifetime stress showed reproducible association and linkage of an SNP in the CRHR1 gene (rs4792887) to suicide attempters exposed to low levels of stress (P = 0.002), among whom most males were depressed (P = 0.001). The identified allele may represent a part of the genetic susceptibility for suicidality by increasing HPA axis activity upon exposure to low levels of stress.
Geographic Variation in Informed Consent Law: Two Standards for Disclosure of Treatment Risks
Authors: Studdert David M. , Mello Michelle M. , Levy Marin K. , Gruen Russell L. , Dunn Edward J. , Orav E. John , Brennan Troyen A.
Published: March 2007

We analyzed 714 jury verdicts in informed consent cases tried in 25 states in 1985–2002 to determine whether the applicable standard of care (“patient” vs. “professional” standard) affected the outcome. Verdicts for plaintiffs were significantly more frequent in states with a patient standard than in states with a professional standard (27 percent vs. 17 percent, P = 0.02). This difference in outcomes did not hold for other types of medical malpractice litigation (36 percent vs. 37 percent, P = 0.8). The multivariate odds of a plaintiff's verdict were more than twice as high in states with a patient standard than in states with a professional standard (odds ratio = 2.15, 95% confidence interval = 1.32–3.50). The law's expectations of clinicians with respect to risk disclosure appear to vary geographically.