University of Turku

About: University of Turku is a education organization based out in Turku, Finland. It is known for research contribution in the topics: Population & Galaxy. The organization has 16296 authors who have published 45124 publications receiving 1505428 citations. The organization is also known as: Turun yliopisto & Åbo universitet.

Non-Markovianity and reservoir memory of quantum channels: a quantum information theory perspective

Abstract: Quantum technologies rely on the ability to coherently transfer information encoded in quantum states along quantum channels. Decoherence induced by the environment sets limits on the efficiency of any quantum-enhanced protocol. Generally, the longer a quantum channel is the worse its capacity is. We show that for non-Markovian quantum channels this is not always true: surprisingly the capacity of a longer channel can be greater than of a shorter one. We introduce a general theoretical framework linking non-Markovianity to the capacities of quantum channels and demonstrate how harnessing non-Markovianity may improve the efficiency of quantum information processing and communication.

Bactericidal effects of bioactive glasses on clinically important aerobic bacteria.

Abstract: Bioactive glasses (BAGs) have been studied for decades for clinical use, and they have found many dental and orthopedic applications. BAGs have also been shown to have an antibacterial effect e.g., on some oral microorganisms. In this extensive work we show that six powdered BAGs and two sol–gel derived materials have a clear antibacterial effect on 29 clinically important bacterial species. We also incorporated a rapid and accurate flow cytometric (FCM) method to calculate and standardize the numbers of viable bacteria inoculated in the suspensions used in the tests for antibacterial activity. In all materials tested growth inhibition could be demonstrated, although the concentration and time needed for the effect varied depending on the BAG. The most effective glass was S53P4, which had a clear growth-inhibitory effect on all pathogens tested. The sol–gel derived materials CaPSiO and CaPSiO II also showed a strong antibacterial effect. In summary, BAGs were found to clearly inhibit the growth of a wide selection of bacterial species causing e.g., infections on the surfaces of prostheses in the body after implantation.

Sex Differences in the Striatal Dopamine D2 Receptor Binding Characteristics in Vivo

Abstract: OBJECTIVE: The authors investigated whether striatal dopamine D2 receptor binding characteristics in vivo are similar in men and women and whether there are sex-related differences in the decline in D2 receptor density due to aging. METHOD: Striatal D2 receptor density (Bmax), affinity (Kd), and binding potential (Bmax/Kd) were measured with positron emission tomography and [11C]raclopride in 54 healthy subjects (33 men and 21 women). RESULTS: Women had generally lower D2 receptor affinity than men, and this difference was statistically significant in the left striatum. Bmax and Bmax/Kd tended to decline with age twice as fast in men as in women, but the difference did not reach statistical significance. CONCLUSIONS: These results confirm the age-related reduction of D2 receptor density and binding potential in both sexes in vivo. The lower D2 receptor affinity suggests an increased endogenous striatal dopamine concentration in women. This may have implications for the differential vulnerability of men an...

The role of the intestinal microflora for the development of the immune system in early childhood.

Abstract: The intestinal tract performs many different functions; in addition to absorption and digestion it is also the body's largest organ of host defence. Part of the intestinal mucosal barrier function is formed by a common mucosal immune system which provides communication between the different mucosal surfaces of the body. The intestine also contains a microbial ecosystem with a large body of microbes, 1-11/2 kg in an adult. The microbes and their activity have a major impact on the development and functioning of the intestinal immune system and vice versa. This mutual influence also affects the host beyond the intestine. The intestinal colonisation with a balanced microflora is of main importance for the correct development of the immune system. The importance of the intestinal microflora is most clearly seen in germfree animals, but also diseases like atopy are associated with disturbances in the intestinal microflora. This often manifests itself in a low number of bifidobacteria. The use of probiotics or prebiotics to correct this imbalance and modulate the immune activity has received increasing scientific documentation. The precise mechanisms behind these immune modulatory activities are not well understood and require further investigation.

C957T polymorphism of the dopamine D2 receptor (DRD2) gene affects striatal DRD2 availability in vivo

Abstract: C957T polymorphism of the dopamine D2 receptor (DRD2) gene affects striatal DRD2 availability in vivo