7,513 research outputs found
Normal metal tunnel junction-based superconducting quantum interference proximity transistor: the N-SQUIPT
We report the fabrication and characterization of an alternative design for a
superconducting quantum interference proximity transistor (SQUIPT) based on a
normal metal (N) probe. The absence of direct Josephson coupling between the
proximized metal nanowire and the N probe allows us to observe the full
modulation of the wire density of states around zero voltage and current
\textit{via} the application of an external magnetic field. This results into a
drastic suppression of power dissipation which can be as low as a few W. In this context the interferometer allows an improvement of up to
four orders of magnitude with respect to earlier SQUIPT designs, and makes it
ideal for extra-low power cryogenic applications. In addition, the N-SQUIPT has
been recently predicted to be the enabling candidate for the implementation of
coherent caloritronic devices based on proximity effect.Comment: 5 pages, 4 color figure
Enhanced Recovery after Elective Colorectal Surgery - Reasons for Non-Compliance with the Protocol.
Enhanced recovery after surgery (ERAS) protocols for elective colorectal surgery reduce the intensity of postoperative complications, hospital stays and costs. Improvements in clinical outcome are directly proportional to the adherence to the recommended pathway (compliance). The aim of the present study was to analyze reasons for the non-compliance of colorectal surgeries with the ERAS protocol.
A consecutive cohort of patients undergoing elective colorectal surgery was prospectively analyzed with regards to the surgery's compliance with the ERAS protocol. The reason for every single protocol deviation was documented and the decision was categorized based on whether it was medically justified or not.
During the 8-month study period, 76 patients were included. The overall compliance with 22 ERAS items was 76% (96% in the preoperative, 82% in the perioperative, and 63% in the postoperative period). The decision to deviate from the clinical pathway was mainly a medical decision, while patients and nurses were responsible in 26 and 14% of the cases, respectively. However, reasons for non-compliance were medically justified in 78% of the study participants.
'Non-compliance' with the ERAS protocol was observed mostly in the postoperative period. Most deviations from the pathway were decided by doctors and in a majority of cases it appeared that they were due to a medical necessity rather than non-compliance. However, almost a quarter of deviations that were absolutely required are still amenable to improvement
Discrete-row growth of xenon adsorbed on the vicinal Pt(997) surface: Comparison between theory and experiment
Xe exhibits a discrete-row growth mode on the vicinal Pt(997) surface by sequential attachment to the substrate steps. In order to interpret experimental results obtained by grazing incidence helium scattering, potential calculations are performed. A mean-field Hamiltonian within the two-dimensional Ising model is shown to explain the sequential-row growth observed in helium-atom diffraction studies. More specifically, the calculated temperatures for the occurrence of each row depend mainly on the shape of the potential increment due to the steps and countersteps. They are in good agreement with the experimental values associated with maxima in the scattered He intensity versus coverage curves
Uranium exposure of the Swiss population based on 24-hour urinary excretion.
Important regional differences in uranium exposure exist because of varying uranium concentrations in soil, water and food. Comprehensive data on the exposure of the general population to uranium is, however, scarce. Based on the 24-hour urinary excretion, the uranium exposure of the adult Swiss population was assessed in relation to age, sex, place of residence, body mass index (BMI), smoking habit and type of drinking water, as well as risk factors in relation to kidney impairment and indicators of a possible renal dysfunction.
Uranium was quantified in 24-hour urine from a nationwide population-based sample (n = 1393). The ratio 238U/233U was measured for isotope dilution calibration with a sector field inductively coupled plasma mass spectrometer (HR-ICP-MS).
Overall median and 95th percentile were 15 and 67 ng/24 h, respectively. The place of residence significantly influenced urinary uranium excretion. However, most of the highest urinary uranium excretion levels could not be associated to areas known for their elevated uranium concentrations in the drinking water. Sources other than the local drinking water (e.g., bottled water) might be important, too. Gender as well as albumin excretion also had a significant effect on uranium excretion. The latter was, however, strongly dependent on the presence of diabetes mellitus. No association was found for age, BMI, smoking habit or the other examined kidney related variables.
On the basis of uranium exposure, assessed via 24-hour urinary uranium excretion, and current knowledge of the toxicity of naturally occurring uranium, a substantial corresponding health risk for the general adult population is unlikely. However, as long as no specific sensitive biomarker for the biological impact of low-dose chronic uranium exposure has been identified and validated, assessing subtle health impact of such exposure will remain difficult
Characterization of Erbium-Doped Nanoparticles in Transparent Glass Ceramic Optical Fibres
We report on using nanometric mass spectroscopy and molecular dynamics modelling to characterize the composition and structure of self-grown erbium-doped nanoparticles in transparent glass ceramic optical fibres fabricated by modified chemical vapour deposition without post-ceramming
Development and evaluation of double locus sequence typing for molecular epidemiological investigations of Clostridium difficile.
Despite the development of novel typing methods based on whole genome sequencing, most laboratories still rely on classical molecular methods for outbreak investigation or surveillance. Reference methods for Clostridium difficile include ribotyping and pulsed-field gel electrophoresis, which are band-comparing methods often difficult to establish and which require reference strain collections. Here, we present the double locus sequence typing (DLST) scheme as a tool to analyse C. difficile isolates. Using a collection of clinical C. difficile isolates recovered during a 1-year period, we evaluated the performance of DLST and compared the results to multilocus sequence typing (MLST), a sequence-based method that has been used to study the structure of bacterial populations and highlight major clones. DLST had a higher discriminatory power compared to MLST (Simpson's index of diversity of 0.979 versus 0.965) and successfully identified all isolates of the study (100 % typeability). Previous studies showed that the discriminatory power of ribotyping was comparable to that of MLST; thus, DLST might be more discriminatory than ribotyping. DLST is easy to establish and provides several advantages, including absence of DNA extraction [polymerase chain reaction (PCR) is performed on colonies], no specific instrumentation, low cost and unambiguous definition of types. Moreover, the implementation of a DLST typing scheme on an Internet database, such as that previously done for Staphylococcus aureus and Pseudomonas aeruginosa ( http://www.dlst.org ), will allow users to easily obtain the DLST type by submitting directly sequencing files and will avoid problems associated with multiple databases
Merging of Components in Close Binaries: Type Ia Supernovae, Massive White Dwarfs, and Ap stars
The "Scenario Machine" (a computer code designed for studies of the evolution
of close binaries) was used to carry out a population synthesis for a wide
range of merging astrophysical objects: main-sequence stars with main-sequence
stars; white dwarfs with white dwarfs, neutron stars, and black holes; neutron
stars with neutron stars and black holes; and black holes with black holes.We
calculate the rates of such events, and plot the mass distributions for merging
white dwarfs and main-sequence stars. It is shown that Type Ia supernovae can
be used as standard candles only after approximately one billion years of
evolution of galaxies. In the course of this evolution, the average energy of
Type Ia supernovae should decrease by roughly 10%; the maximum and minimum
energies of Type Ia supernovae may differ by no less than by a factor of 1.5.
This circumstance should be taken into account in estimations of parameters of
acceleration of the Universe. According to theoretical estimates, the most
massive - as a rule, magnetic - white dwarfs probably originate from mergers of
white dwarfs of lower mass. At least some magnetic Ap and Bp stars may form in
mergers of low-mass main sequence stars (<1.5 mass of the Sun) with convective
envelopes.Comment: 15 pages, 4 figure
Normal subgroups in the Cremona group (long version)
Let k be an algebraically closed field. We show that the Cremona group of all
birational transformations of the projective plane P^2 over k is not a simple
group. The strategy makes use of hyperbolic geometry, geometric group theory,
and algebraic geometry to produce elements in the Cremona group that generate
non trivial normal subgroups.Comment: With an appendix by Yves de Cornulier. Numerous but minors
corrections were made, regarding proofs, references and terminology. This
long version contains detailled proofs of several technical lemmas about
hyperbolic space
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