Inversion methods for interpretation of asteroid lightcurves

We have developed methods of inversion that can be used in the determination of the three-dimensional shape or the albedo distribution of the surface of a body from disk-integrated photometry, assuming the shape to be strictly convex. In addition to the theory of inversion methods, we have studied the practical aspects of the inversion problem and applied our methods to lightcurve data of 39 Laetitia and 16 Psyche

Pressure of the Standard Model Near the Electroweak Phase Transition

We extend our previous determination of the thermodynamic pressure of the Standard Model so that the result can be applied down to temperatures corresponding to the electroweak crossover. This requires a further resummation which can be cleanly organised within the effective theory framework. The result allows for a precise determination of the expansion rate of the Universe for temperatures around the electroweak crossover.Comment: 16 pages, 6 figures. v2: published versio

Attitudes of sixth form female students towards the IT field

It is well-known that girls are not interested in computer science, information systems (IS) and software engineering studies. While the underlying reasons for this phenomenon have been studied in the US, Canada and Australia, only a few studies have been carried out in Europe and none in Scandinavia. To fill this gap in the research, we have analyzed the qualitative responses of 64 female sixth-form students concerning their attitudes towards studying information technology (IT), including Computer Science, Information Systems and Software engineering disciplines, and their views on IT as a profession. The results suggest that the IT field is seen in quite a positive light by the girls. Although many of the respondents do not consider IT to be their profession, they nevertheless have positive attitudes towards the field. According to the respondents, the field is growing and developing; it is respected, and seen as the field of future. Girls who want to become IT professionals see that the profession entails good employment possibilities and benefits and is respected. Some girls have negative views towards the field. These views illustrate the underlying reasons that these girls do not want to study IT. These girls did not perceive the field to be human-related (the work is only computer-related, according to the respondents). The need for skills in mathematics and physics are also listed as key reasons that some girls do not want to become IT students The results of the study suggest that there is a need to clarify among sixth form students the fact that IT jobs can be divided into computer science, information systems and software engineering, all of which require different competences

Pressure of the Standard Model at High Temperatures

We compute the pressure of the standard model at high temperatures in the symmetric phase to three loops, or to O(g^5) in all coupling constants. We find that the terms of the perturbative expansion in the SU(2) + Higgs sector decrease monotonically with increasing order, but the large values of the strong coupling constant g_s and the Yukawa coupling of the top quark g_Y make the expansion in the full theory converge more slowly. The final result is observed to be about 10% smaller than the ideal gas pressure commonly used in cosmological calculations.Comment: 30 pages, 4 figures. v2: one reference added, minor revisions, accepted for publication in JHE

Structural Effects of Small Molecules on Phospholipid Bilayers Investigated by Molecular Simulations

We summarize and compare recent Molecular Dynamics simulations on the interactions of dipalmitoylphosphatidylcholine (DPPC) bilayers in the liquid crystalline phase with a number of small molecules including trehalose, a disaccharide of glucose, alcohols, and dimethylsulfoxide (DMSO). The sugar molecules tend to stabilize the structure of the bilayer as they bridge adjacent lipid headgroups. They do not strongly change the structure of the bilayer. Alcohols and DMSO destabilize the bilayer as they increase its area per molecule in the bilayer plane and decrease the order parameter. Alcohols have a stronger detrimental effect than DMSO. The observables which we compare are the area per molecule in the plane of the bilayer, the membrane thickness, and the NMR order parameter of DPPC hydrocarbon tails. The area per molecule and the order parameter are very well correlated whereas the bilayer thickness is not necessarily correlated with them.Comment: 8 pages, 3 figures, accepted to Fluid Phase Equilibri