37 research outputs found
Memory cell based on a Josephson junction
The Josephson junction has a doubly degenerate ground state with
the Josephson phases . We demonstrate the use of such a
Josephson junction as a memory cell (classical bit), where writing is done by
applying a magnetic field and reading by applying a bias current. In the
"store" state, the junction does not require any bias or magnetic field, but
just needs to stay cooled for permanent storage of the logical bit.
Straightforward integration with Rapid Single Flux Quantum logic is possible.Comment: to be published in AP
The effect of normal and insulating layers on 0-π transitions in Josephson junctions with a ferromagnetic barrier
Using the Usadel approach, we provide a formalism that allows us to calculate the critical current density of 21 different types of Josephson junctions (JJs) with a ferromagnetic (F) barrier and additional insulating (I) or/and normal (N) layers inserted between the F layer and superconducting (S) electrodes. In particular, we obtain that in SFS JJs, even a thin additional N layer between the S layer and F layer may noticeably change the thickness dF of the F layer at which the 0-π transitions occur. For certain values of dF, a 0-π transition can even be achieved by changing only the N layer thickness. We use our model to fit experimental data of SIFS and SINFS tunnel junctions
The effect of normal and insulating layers on 0-πtransitions in Josephson junctions with a ferromagnetic barrier
Using the Usadel approach, we provide a formalism that allows us to calculate the critical current density of 21 different types of Josephson junctions (JJs) with a ferromagnetic (F) barrier and additional insulating (I) or/and normal (N) layers inserted between the F layer and superconducting (S) electrodes. In particular, we obtain that in SFS JJs, even a thin additional N layer between the S layer and F layer may noticeably change the thickness of the F layer at which the 0-π transitions occur. For certain values of a 0-π transition can even be achieved by changing only the N layer thickness. We use our model to fit experimental data of SIFS and SINFS tunnel junctions
Diversity of Staphylococcus aureus Isolates in European Wildlife
Staphylococcus aureus is a well-known colonizer and cause of infection among
animals and it has been described from numerous domestic and wild animal
species. The aim of the present study was to investigate the molecular
epidemiology of S. aureus in a convenience sample of European wildlife and to
review what previously has been observed in the subject field. 124 S. aureus
isolates were collected from wildlife in Germany, Austria and Sweden; they
were characterized by DNA microarray hybridization and, for isolates with
novel hybridization patterns, by multilocus sequence typing (MLST). The
isolates were assigned to 29 clonal complexes and singleton sequence types
(CC1, CC5, CC6, CC7, CC8, CC9, CC12, CC15, CC22, CC25, CC30, CC49, CC59, CC88,
CC97, CC130, CC133, CC398, ST425, CC599, CC692, CC707, ST890, CC1956, ST2425,
CC2671, ST2691, CC2767 and ST2963), some of which (ST2425, ST2691, ST2963)
were not described previously. Resistance rates in wildlife strains were
rather low and mecA-MRSA isolates were rare (n = 6). mecC-MRSA (n = 8) were
identified from a fox, a fallow deer, hares and hedgehogs. The common cattle-
associated lineages CC479 and CC705 were not detected in wildlife in the
present study while, in contrast, a third common cattle lineage, CC97, was
found to be common among cervids. No Staphylococcus argenteus or
Staphylococcus schweitzeri-like isolates were found. Systematic studies are
required to monitor the possible transmission of human- and livestock-
associated S. aureus/MRSA to wildlife and vice versa as well as the possible
transmission, by unprotected contact to animals. The prevalence of S.
aureus/MRSA in wildlife as well as its population structures in different
wildlife host species warrants further investigation
A Field Guide to Pandemic, Epidemic and Sporadic Clones of Methicillin-Resistant Staphylococcus aureus
In recent years, methicillin-resistant Staphylococcus aureus
(MRSA) have become a truly global challenge. In addition to the long-known
healthcare-associated clones, novel strains have also emerged outside of the
hospital settings, in the community as well as in livestock. The emergence and
spread of virulent clones expressing Panton-Valentine leukocidin (PVL) is an
additional cause for concern. In order to provide an overview of pandemic,
epidemic and sporadic strains, more than 3,000 clinical and veterinary isolates
of MRSA mainly from Germany, the United Kingdom, Ireland, France, Malta, Abu
Dhabi, Hong Kong, Australia, Trinidad & Tobago as well as some reference
strains from the United States have been genotyped by DNA microarray analysis.
This technique allowed the assignment of the MRSA isolates to 34 distinct
lineages which can be clearly defined based on non-mobile genes. The results
were in accordance with data from multilocus sequence typing. More than 100
different strains were distinguished based on affiliation to these lineages,
SCCmec type and the presence or absence of PVL. These
strains are described here mainly with regard to clinically relevant
antimicrobial resistance- and virulence-associated markers, but also in relation
to epidemiology and geographic distribution. The findings of the study show a
high level of biodiversity among MRSA, especially among strains harbouring
SCCmec IV and V elements. The data also indicate a high
rate of genetic recombination in MRSA involving SCC elements, bacteriophages or
other mobile genetic elements and large-scale chromosomal replacements
A Field Guide to Pandemic, Epidemic and Sporadic Clones of Methicillin-Resistant Staphylococcus aureus
In recent years, methicillin-resistant Staphylococcus aureus
(MRSA) have become a truly global challenge. In addition to the long-known
healthcare-associated clones, novel strains have also emerged outside of the
hospital settings, in the community as well as in livestock. The emergence and
spread of virulent clones expressing Panton-Valentine leukocidin (PVL) is an
additional cause for concern. In order to provide an overview of pandemic,
epidemic and sporadic strains, more than 3,000 clinical and veterinary isolates
of MRSA mainly from Germany, the United Kingdom, Ireland, France, Malta, Abu
Dhabi, Hong Kong, Australia, Trinidad & Tobago as well as some reference
strains from the United States have been genotyped by DNA microarray analysis.
This technique allowed the assignment of the MRSA isolates to 34 distinct
lineages which can be clearly defined based on non-mobile genes. The results
were in accordance with data from multilocus sequence typing. More than 100
different strains were distinguished based on affiliation to these lineages,
SCCmec type and the presence or absence of PVL. These
strains are described here mainly with regard to clinically relevant
antimicrobial resistance- and virulence-associated markers, but also in relation
to epidemiology and geographic distribution. The findings of the study show a
high level of biodiversity among MRSA, especially among strains harbouring
SCCmec IV and V elements. The data also indicate a high
rate of genetic recombination in MRSA involving SCC elements, bacteriophages or
other mobile genetic elements and large-scale chromosomal replacements
Constructed wetlands for combined sewer overflow treatment: A state-of-the-art review
International audienceCombined sewer overflows (CSOs) are a major source of surface water pollution and degradation. This is particularly visible where sewage collectionwith combined sewer and centralized treatment arewell established, such as in Europe and North America: an over whelming number of surface water bodies are in insufficient status of ecology, hydrology and physico-chemical parameters. Therefore, several countries have started implementing constructed wetlands (CWs) as mainstream on-spot treatment. This paper summarizes the main design approaches that can be adopted. We identified eight different schemes for the implementation of CSO-CWs, based on our international experience and documented by a literature analysis. The performance review includes conventional water quality parameters, as well as pathogen and emergent contaminant removal. Furthermore, modelling tools for advanced design and for understanding a wide applicability of these green infrastructures are presented. This paper also provides a review on other side benefits offered by the adoption of Nature-Based Solutions for CSO treatment, such as ecosystem services, and the most common issues related to their operation and maintenance. Our analysis has produced a list of key factors for design and operation, all derived from full-scale installations in operation up to more than ten years