Sequentiality versus Simultaneity: Interrelated Factor Demand.

A structural model is developed and estimated by a maximum likelihood routine to investigate interrelated factor demand subject to nonconvex adjustment costs. The dataset concerns Norwegian plants operating in manufacturing industries and it covers the period 1993-2005. The estimates indicate that it is advantageous to adjust the stock of labour and capital simultaneously. The cost advantage of simultaneous changes is small for capital but is large for labour. The empirical results suggest that when estimating separate factor demand models the bias of parameter estimates is most severe in case of labour demand.Factor Demand; Labour; Capital; Interrelation; Nonconvex Adjustment Costs.

Sequentiality versus Simultaneity: Interrelated Factor Demand

A structural model is developed and estimated by a maximum likelihood routine to investigate interrelated factor demand subject to nonconvex adjustment costs. The dataset concerns Norwegian plants operating in manufacturing industries and it covers the period 1993-2005. The estimates indicate that it is advantageous to adjust the stock of labour and capital simultaneously. The cost advantage of simultaneous changes is small for capital but is large for labour. The empirical results suggest that when estimating separate factor demand models the bias of parameter estimates is most severe in case of labour demand.factor demand, labour, capital, interrelation, nonconvex adjustment costs

Influence of professionally assessed normative orthodontic treatment need on adult OHRQoL

Introduction: There is an increasing amount of research regarding the impact of malocclusions on OHRQoL. Reviews on this topic has mostly focused on children and adolescents, and therefore the aim of this thesis is to investigate the impact of professionally assessed normative orthodontic treatment need on adult OHRQOL. Materials and methods: Four electronic databases (PubMed, EMBASE, Cochrane library and Google Scholar) were searched using a search syntax including orthodontic treatment need, malocclusion, OHRQoL. The following inclusion criteria were used: Adult study population, healthy study participants, no previous or ongoing orthodontic treatment, a focus on malocclusion and quality of life, malocclusions assessed by professionals, OHRQoL estimated using validated questionnaires, and full-text articles written in English or in the Scandinavian languages. Methodical quality was assessed according to the Newcastle-Ottawa scale. Results: A total of 1152 titles and abstracts were identified after duplicates were removed and 11 studies were included for the final analysis. The studies represented a large variation in sample size, methodology and geographical spread and were assessed as being of low to moderate methodological quality. All 11 studies presented significant associations between malocclusion (indices or specific malocclusions) and OHRQoL (domains or total scores). Regression analyses disclosed most of the associations as weak to moderate. Conclusion: Adults with considerable malocclusions have significantly poorer OHRQoL than people with occlusions near or within norms. Future studies would benefit from longitudinal studies with large representative samples

Are there sharp fractional charges in Luttinger liquids?

We examine charge fractionalization by chiral separation in a one-dimensional fermion system described by Luttinger liquid theory. The focus is on the question of whether the fractional charges are quantum mechanically sharp, and in the analysis we make a distinction between the global charge, which is restricted by boundary conditions, and the local charge where a background contribution is subtracted. We show, by way of examples, that fractional charges of arbitrary values, all which are quantum mechanically sharp, can be introduced by different initial conditions. Since the system is gapless, excitations of arbitrary low frequency contribute to the fluctuations, it is important to make a precise definition of sharp charges, and this we we do by subtraction of the ground state contribution. We very briefly comment on the relevance of our analysis for proposed experiments.Comment: One reference update

Charge Fractionalization on Quantum Hall Edges

We discuss the propagation and fractionalization of localized charges on the edges of quantum Hall bars of variable widths, where interactions between the edges give rise to Luttinger liquid behavior with a non-trivial interaction parameter g. We focus in particular on the separation of an initial charge pulse into a sharply defined front charge and a broader tail. The front pulse describes an adiabatically dressed electron which carries a non-integer charge, which is \sqrt{g} times the electron charge. We discuss how the presence of this fractional charge can, in principle, be detected through measurements of the noise in the current created by tunneling of electrons into the system. The results are illustrated by numerical simulations of a simplified model of the Hall bar.Comment: 15 page

0110: Exercise stress echocardiography in secondary mitral regurgitation: impact of pulmonary hypertension

BackgroundSecondary mitral regurgitation (MR) is a serious and frequent complication of dilated cardiomyopathy and/or coronary artery disease. The impact of exerxise pulmonary hypertension (ExPHT) on outcome in patients with secondary MR is unknown.Method and resultsAll patients with secondary MR, sinus rhythms, narrow QRS (<120ms) and referred for exercise stress echocardiography with quantifiable exercise systolic pulmonary arterial pressure (SPAP), were included in this study (n=159, 65±11 years, 66% of male). Resting and ExPHT were defined as a systolic pulmonary arterial pressure (SPAP) >50mmHg and >60mmHg, respectively. ExPHT was more frequent than resting PHT (40% vs. 13%, p<0.0001). There was no significant difference between patients with or without ExPHT regarding demographic and clinical data, as well as medication. Using multiple linear regression, exercise SPAP was determined by resting SPAP (β=0.94±0.1, p<0.0001), exercise MR severity (β=0.58±0.1, p<0.0001), and resting e’-wave velocity (β=–1.3±0.4, p=0.004). During a mean follow-up of 35±11 months, 60 major adverse cardiovascular events occured. The incidence of combined cardiac event was significantly higher in patients with ExPHT as compared to those without ExPHT (2-year: 11±3 vs. 28±6%; 4-year: 20±5 vs. 40±7%, p<0.0001). Similarly, patients with ExPHT demonstrated significantly reduced survival (2-year: 88±4 vs. 99±1%; 4-year: 62±8% vs. 94±2%, p<0.0001). In multivariate Cox proportional Hazard model, after adjustment for age, sex, left ventricular volumes, both resting and exercise diastolic function and resting MR severity, ExPHT remains significantly associated with high risk of combined cardiac event (Hazard ratio=3.7, 95% of CI: 1.9-7.2, p<0.0001).ConclusionIn patients with secondary MR, ExPHT may be frequent and mainly determined by resting SPAP, LV diastolic burden markers and exercise MR severity. ExPHT is a powerful predictor of poor outcome and is associated with a 3.7-fold increase in risk of cardiac event. These results further highlight the usefulness of exercise stress echocardiography for the management and the risk stratification of these patients

Approaches to Studying: A Cross-Sectional Comparison of Occupational Therapy Students in Six Education Programs in Norway

Students’ approaches to studying have been associated with their academic performance. Although previous research suggests that the cultural and educational context may influence approaches to studying, few studies have investigated differences in study approaches across education programs. The aim of this study was to examine whether approaches to studying differed among occupational therapy students enrolled in six different educational programs in Norway. From a population of 308 students, 187 first-year occupational therapy students in six educational programs in Norway were recruited. The students provided their sociodemographic information and completed the Approaches and Study Skills Inventory for Students (ASSIST), and group differences were analyzed with Chi-square tests and one-way analyses of variance. Scores on the deep and surface approach scales did not differ significantly among the students in the six educational programs, while there was an overall difference in scores on the strategic approach scale. Group differences regarding the subscales were minor, and only a few of the pairwise differences reached statistical significance. Differences at the education program level appear not to be important for the interpretation of differences in study approaches among students

Mental Health and Access to Active Labor Market Programs

This paper examines the often-overlooked precondition for successful implementation of active labor market policy, namely equal access to labor market programs. Focusing on a cohort of social assistance recipients, we compare program participation between individuals who were eligible for vocational training and had reported psychological distress, to possible participants with other health or social challenges. The study covers a period of six years. The results indicate that social services prioritize training for those without mental health problems. This is true independently of observed differences between the two groups in terms of demographic and human capital characteristics, work motivation and self-efficacy. Hence, the study concludes that there seems to be a mental health access bias in program participation among disadvantaged groups. Policy makers and future research should address possible organizational barriers to equal program acces