Project on comparison of structural parameters and electron density maps of oxalic acid dihydrate

Results obtained from four X-ray and five neutron data sets collected under a project sponsored by the Commission on Charge, Spin and Momentum Densities are analyzed by comparison of thermal parameters, positional parameters and X - N electron density maps. Three sets of theoretical calculations are also included in the comparison. Though several chemically significant features are reproduced in all the experimental density maps, differences in detail occur which caution against overinterpretation of the maps. Large differences between vibrational tensor elements Uij are observed which can often not be corrected by the scaling of all temperature parameters in a set. Positional parameters are reproducible to precisions of 0.001 Å or better. The biggest discrepancies between theoretical and experimental deformation density maps occurs in the lone-pair regions where peaks are higher in the theoretical maps. However, this comparison may be affected by inadequacies in the thermal-motion formalism which must be invoked before experimental and theoretical maps can be compared in a quantitative way

EARLY ONSET OF MAJOR DEPRESSIVE DISORDER AND ITS CONSEQUENCES FOR RECURRENCE AND CO-MORBIDITY: CONTRASTING THE EXPERIENCES OF SINGLE AND MARRIED MOTHERS

The purpose of this study was to determine whether the association of an early onset of major depressive disorder with the risk for recurrence of depression and psychiatric comorbidity is magnified among single mothers in contrast to married mothers. The data for this study were collected as part of a three-wave cohort study of 518 single and 502 married mothers in London, Ontario. The women were interviewed with the Michigan version of the Composite International Diagnostic Inventory. Results indicate that an early onset of depression was significantly associated with recurrence, but only modestly associated with other psychiatric comorbidity. Examined separately for single and married mothers, we found that being a single mother with an early onset of depression puts a woman at the highest risk of a psychiatric morbidity

Testing for inherited thrombophilia does not reduce the recurrence of venous thrombosis\ud

Background: Inherited thrombophilia is only weakly associated with recurrence in patients with a first venous thrombosis (VT). In spite of this, thrombophilia testing is often performed in these patients. Positive results may influence patient management such as prolonged anticoagulant treatment or intensified prophylaxis in high-risk situations. Objective: To investigate whether thrombophilia testing reduces the risk of recurrent VT by virtue of these management alterations. Methods: From a large case–control study of patients (MEGA study), aged 18–70 years, with a first VT between 1999 and 2004, we selected 197 patients who had had a recurrence during follow-up. We compared the incidence of thrombophilia testing to that of a control cohort of 324 patients. We calculated the odds ratio (OR) for recurrent thrombosis in tested vs. non-tested patients. Only patients who were tested before recurrence were regarded as tested. All first and recurrent thrombotic events were objectively confirmed. Results: Thrombophilia tests were performed in 35% of cases and in 30% of controls. The OR for recurrence was 1.2 [95% confidence interval (CI) 0.9–1.8] for tested vs. non-tested patients. After correction for age, sex, family history, geographic region, presence of clinical risk factors, and year of first VT, the OR remained unchanged. Discussion: Thrombophilia testing in patients with a first VT does not reduce the incidence of recurrence in clinical practice.\u

The 2PI finite temperature effective potential of the O(N) linear sigma model in 1+1 dimensions, at next-to-leading order in 1/N

We study the O(N) linear sigma model in 1+1 dimensions. We use the 2PI formalism of Cornwall, Jackiw and Tomboulis in order to evaluate the effective potential at finite temperature. At next-to-leading order in a 1/N expansion one has to include the sums over "necklace" and generalized "sunset" diagrams. We find that - in contrast to the Hartree approximation - there is no spontaneous symmetry breaking in this approximation, as to be expected for the exact theory. The effective potential becomes convex throughout for all parameter sets which include N=4,10,100, couplings lambda=0.1 and 0.5, and temperatures between 0.2 and 1. The Green's functions obtained by solving the Schwinger-Dyson equations are enhanced in the infrared region. We also compare the effective potential as function of the external field phi with those obtained in various other approximations.Comment: 19 pages, 9 figures; v2: references added, some changes in the tex

Transition from Knudsen to molecular diffusion in activity of absorbing irregular interfaces

We investigate through molecular dynamics the transition from Knudsen to molecular diffusion transport towards 2d absorbing interfaces with irregular geometry. Our results indicate that the length of the active zone decreases continuously with density from the Knudsen to the molecular diffusion regime. In the limit where molecular diffusion dominates, we find that this length approaches a constant value of the order of the system size, in agreement with theoretical predictions for Laplacian transport in irregular geometries. Finally, we show that all these features can be qualitatively described in terms of a simple random-walk model of the diffusion process.Comment: 4 pages, 4 figure

Incubators as enablers for academic entrepreneurship

The key questions that academics are struggling with are: can one teach entrepreneurship and how can it be embedded into a science, technology or engineering curriculum while maintaining high academic standards. Furthermore, prior research has pointed to a mismatch between the competencies of the highest educated and most specialised students of our academic system and the expectations of the (corporate) market (Anseel, 2012; De Grande, De Boyser, Vandevelde et al, 2011). Therefore, this paper investigates the opportunities offered by 'learning-by-doing' in an ecosystem perspective. The organisation iMinds somehow acts as network integrator for research and entrepreneurship in ICT in Flanders. In this role, iMinds collaborates with universities and university colleges and other actors in the ecosystem supporting entrepreneurship. The various mechanisms deployed to support entrepreneurship and the development of entrepreneurial skills amongst (under) graduate students are analysed. These include extra-curricular activities (workshop and coaching series). Additionally, these activities are embedded in and intertwined with the development of entrepreneurial behaviour and skills in the classical curriculum using new learning methods. Some examples can be found at Karel de Grote University College (the so-called 'The Company' minor) and at Ghent University ('student-entrepreneur' status). The enabler to drive this evolution forward is the inclusion of incubators as part of the learning system. Students that want to start a business can spend 2 years on an MBA or join an incubator; the latter generally being accepted as a faster and more effective way of learning. Results can be seen at three levels. Firstly, it results in an increased awareness of entrepreneurship as viable career opportunity. Secondly, these programs increase the number of student start-ups, which additionally are better equipped to grow and prosper. Since the program's start in 2011, iMinds has received eight applications for student start-ups and has supported four. Furthermore, about 25 students have made use of the (physical) incubator space. Thirdly, this ecosystem approach results in an increased cooperation between universities (e.g., at the level of doctoral schools) and with other network actors, leading to spillover effects and more effective use of proceeds. The universities of the future will intertwine academic education with entrepreneurship. The end goal should not be that all students become entrepreneurs, but the development of entrepreneurial skills will be beneficial to all stakeholders. This requires collaboration with these stakeholders in the ecosystem, including incubators as further enablers of entrepreneurial behaviour

Mesostructure of Mesoporous Silica/Anodic Alumina Hierarchical Membranes Tuned with Ethanol

Hierarchically structured membranes composed of mesoporous silica embedded inside the channels of anodic alumina (MS-AAM) were synthesized using the aspiration method. Ethanol is shown to have a significant effect on the type and organization of the mesoporous silica phase. Detailed textural analysis revealed that the pore size distribution of the mesoporous silica narrows and the degree of ordering increases with decreasing ethanol concentration used in the synthesis mixture. The silica mesopores were synthesized with pores as small as 6 nm in diameter, with the channel direction oriented in lamellar, circular, and columnar directions depending on the ethanol content. This study reveals ethanol concentration as a key factor behind the synthesis of an ordered mesoporous silica-anodic alumina membrane that can increase its functionality for membrane-based applications