Employment status passages and psychosocial well-being.

Medical students entering the labor market were studied to find out whether the improvement of psychosocial well-being depends on characteristics of their careers. Psychosocial well-being was described on the basis of psychosomatic stress symptoms, psychological distress (General Health Questionnaire), and strain resistance resources (Sense of Coherence). The 3-year follow-up showed that among women the improvement of strain resistance resources was delayed in the group with several entries into work. Among men the findings suggested associations between stress symptoms and career characteristics. Most of the results, however, did not support the hypothesis about the division of the participants into those with a stable career and improving well-being and those with a fragmented career and low well-being. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Development of Cr and Al Pack Cementation Coatings on Co-Based γ/γ′ Superalloys

Metallurgical and Materials Transactions A - Co-based superalloys have been developed as candidate materials to replace Ni-based superalloys in hot sections of turbine engines, however, their...     

Passive and transpassive behaviour of CoCrMo in simulated biological solutions

In this work, the behaviour of a CoCrMo alloy under simulated body conditions was investigated. More specifically, the electrochemical properties of the alloy and the relevant mechanisms in the passive and transpassive states were studied in detail. Electrochemical techniques such as potentiodynamic and potentiostatic polarisation, cyclic voltammetry, rotating disc electrode and electrochemical impedance spectroscopy were employed. Further, ex situ X-ray photoelectron spectroscopy analysis of the passive films was carried out. A good correlation between the results obtained from all the experimental techniques was achieved. Overall, it was found that the passive film on CoCrMo changed in composition and thickness with both potential and time. The passive behaviour of the CrCrMo alloy is due to a formation an oxide film highly enriched with Cr (≈90% Cr oxides) on the alloy surface. The passive and transpassive behaviour of the alloy is hence dominated by the alloying element Cr. In the transpassive region, strong thickening of the oxide film takes place, combined with a change in the composition of the film, and strongly increased dissolution rate. In the transpassive region, all alloying elements dissolve according to the composition of the alloy. The metal ion release is also very strongly enhanced by cyclic variation of the potential between reducing and oxidizing conditions. In this case, during activation/repassivation cycles, cobalt dissolution is greater than expected from the composition of the alloy. Therefore, active dissolution behaviour is mainly dominated by the alloying element Co.     

A new method for evaluating the subjective image quality of photographs: dynamic reference

The Dynamic Reference (DR) method has been developed for subjective image quality experiments in which original or undistorted images are unavailable. The DR method creates reference image series from test images. Reference images are presented to observers as a slide show prior to evaluating their quality. As the observers view the set of reference images, they determine the overall variation in quality within the set of test images. This study compared the performance of the DR method to that of the standardized absolute category rating (ACR) and paired comparison (PC) methods. We measured the performance of each method in terms of time effort and discriminability. The results showed that the DR method is faster than the PC method and more accurate than the ACR method. The DR method is especially suitable for experiments that require highly accurate results in a short time.     

On the human ability to discriminate audio ambiances from similar locations of an urban environment

When developing advanced location-based systems augmented with audio ambiances, it would be cost-effective to use a few representative samples from typical environments for describing a larger number of similar locations. The aim of this experiment was to study the human ability to discriminate audio ambiances recorded in similar locations of the same urban environment. A listening experiment consisting of material from three different environments and nine different locations was carried out with nineteen subjects to study the credibility of audio representations for certain environments which would diminish the need for collecting huge audio databases. The first goal was to study to what degree humans are able to recognize whether the recording has been made in an indicated location or in another similar location, when presented with the name of the place, location on a map, and the associated audio ambiance. The second goal was to study whether the ability to discriminate audio ambiances from different locations is affected by a visual cue, by presenting additional information in form of a photograph of the suggested location. The results indicate that audio ambiances from similar urban areas of the same city differ enough so that it is not acceptable to use a single recording as ambience to represent different yet similar locations. Including an image was found to increase the perceived credibility of all the audio samples in representing a certain location. The results suggest that developers of audio-augmented location-based systems should aim at using audio samples recorded on-site for each location in order to achieve a credible impression.     

Nanowire encapsulation with polymer for electrical isolation and enhanced optical properties

Light management and electrical isolation are essential for the majority of optoelectronic nanowire (NW) devices.Here,we present a cost-effective technique,based on vapor-phase deposition of parylene-C and subsequent annealing,that provides conformal encapsulation,anti-reflective coating,improved optical properties,and electrical insulation for GaAs nanowires.The process presented allows facile encapsulation and insulation that is suitable for any nanowire structure.In particular,the parylene-C encapsulation functions as an efficient antireflection coating for the nanowires,with reflectivity down to ＜1％ in the visible spectrum.Furthermore,the parylene-C coating increases photoluminescence intensity,suggesting improved light guiding to the NWs.Finally,based on this process,a NW LED was fabricated,which showed good diode performance and a clear electroluminescence signal.We believe the process can expand the fabrication possibilities and improve the performance of optoelectronic nanowire devices.     

Automated contracting in distributed manufacturing among independent companies

So far, most distributed scheduling systems have been designed for cooperative agents, and are inappropriate for self-interested agents, as for example in inter-firm interactions such as virtual enterprises. This paper discusses issues that arise in extending automated contracting to operate among such self-interested agents. We construct a leveled commitment contracting protocol that allows self-interested agents to efficiently accommodate future events by having the possibility of unilaterally decommitting from a contract based on local reasoning. A decommitment penalty is assigned to both agents in a contract to be freed from the contract, an agent only pays this penalty to the other party. It is formally shown that this leveled commitment feature in a contracting protocol increases Pareto efficiency of deals and can enable contracts by making them individually rational when no full commitment contract can. The analysis is nontrivial because self-interested agents decommit manipulatively a Nash equilibrium analysis of the decommitting game is necessary.     

The effect of differentiation inducers on the integrin expression of K562 erythroleukemia cells

The DNA sequences of the recA gene from 25 strains of bacteria are known. The evolution of these recA gene sequences, and of the derived RecA protein sequences, is examined, with special reference to the effect of variations in genomic G + C content. From the aligned RecA protein sequences, phylogenetic trees have been drawn using both distance matrix and maximum parsimony methods. There is a broad concordance between these trees and those derived from other data (largely 16S ribosomal RNA sequences). There is a fair degree of certainty in the relationships among the "Purple" or Proteobacteria, but the branching pattern between higher taxa within the eubacteria cannot be reliably resolved with these data.     

Compressing Two-Dimensional Routing Tables

We consider an algorithmic problem that arises in the context of routing tables used by Internet routers. The Internet addressing scheme is hierarchical, where a group of hosts are identified by a prefix that is common to all the hosts in that group. Each host machine has a unique 32-bit address. Thus, all traffic between a source group s and a destination group d can be routed along a particular route c by maintaining a routing entry (s, d, c) at all intermediate routers, where s and d are binary bit strings. Many different routing tables can achieve the same routing behavior. In this paper we show how to compute the most compact routing table. In particular, we consider the following optimization problem: given a routing table D with N entries of the form (s, d, c) , determine a conflict-free routing table with fewest entries that has the same routing behavior as D. If the source and destination fields have up to w bits, and there are at most K different route values, then our algorithm runs in worst-case time O( NK w2) .