1,156 research outputs found
Evidence of Cooper pair pumping with combined flux and voltage control
We have experimentally demonstrated pumping of Cooper pairs in a
single-island mesoscopic structure. The island was connected to leads through
SQUID (Superconducting Quantum Interference Device) loops. Synchronized flux
and voltage signals were applied whereby the Josephson energies of the SQUIDs
and the gate charge were tuned adiabatically. From the current-voltage
characteristics one can see that the pumped current increases in 1e steps which
is due to quasiparticle poisoning on the measurement time scale, but we argue
that the transport of charge is due to Cooper pairs.Comment: 4 page
Tying the extended family knot : Grandparents’ influence on educational achievement
In present-day western societies grandparents and grandchildren have longer years of shared lifetime than ever before. We investigate whether children with more grandparent resources have a higher probability of achieving the general secondary degree compared with children with fewer resources, or whether shared lifetime with grandparents increases the probability of achieving the general secondary degree. We use high-quality Finnish Census Panel data and apply sibling random and fixed-effects models that also control for all unobserved factors shared by siblings. Grandparents’ education and socioeconomic status have only a limited ability to explain a grandchild’s educational achievement. However, the sibling fixed-effects models reveal that every shared year between grandparents and grandchildren increases a grandchild’s likelihood of completing general secondary education by 1 percentage point, on average. The effect of shared lifetime is conditional on grandparental type, family resources, and the size of the extended family. Maternal grandmothers have a positive effect on grandchildren’s education in low-income families. Paternal grandmothers provide a link to the resources available through the extended family network, independent of their own resources. The same effects were not observed for grandfathers.Peer reviewe
Loss of correlation between HIV viral load and CD4+ T-cell counts in HIV/HTLV-1 co-infection in treatment naive Mozambican patients
Seven hundred and four HIV-1/2-positive, antiretroviral therapy (ART) naĂŻve patients were screened for HTLV-1 infection. Antibodies to HTLV-1 were found in 32/704 (4.5%) of the patients. Each co-infected individual was matched with two HIV mono-infected patients according to World Health Organization clinical stage, age +/-5 years and gender. Key clinical and laboratory characteristics were compared between the two groups. Mono-infected and co-infected patients displayed similar clinical characteristics. However, co-infected patients had higher absolute CD4+ T-cell counts (P = 0.001), higher percentage CD4+ T-cell counts (P < 0.001) and higher CD4/CD8 ratios (P < 0.001). Although HIV plasma RNA viral loads were inversely correlated with CD4+ T-cell-counts in mono-infected patients (P < 0.0001), a correlation was not found in co-infected individuals (P = 0.11). Patients with untreated HIV and HTLV-1 co-infection show a dissociation between immunological and HIV virological markers. Current recommendations for initiating ART and chemoprophylaxis against opportunistic infections in resource-poor settings rely on more readily available CD4+ T-cell counts without viral load parameters. These guidelines are not appropriate for co-infected individuals in whom high CD4+ T-cell counts persist despite high HIV viral load states. Thus, for co-infected patients, even in resource-poor settings, HIV viral loads are likely to contribute information crucial for the appropriate timing of ART introduction
Anesthesia for deep brain stimulation in traumatic brain injury-induced hemidystonia
Deep brain stimulation in an awake patient presents several unique challenges to the anesthesiologist. It is important to understand the various stages of the procedure and the complexities of anesthetic management in order to have a successful surgical outcome and provide a safe environment for the patient
Anesthesia for deep brain stimulation in traumatic brain injury-induced hemidystonia.
Deep brain stimulation in an awake patient presents several unique challenges to the anesthesiologist. It is important to understand the various stages of the procedure and the complexities of anesthetic management in order to have a successful surgical outcome and provide a safe environment for the patient
Higher-order mesoscopic fluctuations in quantum wires: Conductance and current cumulants
We study conductance cumulants and current cumulants
related to heat and electrical transport in coherent mesoscopic quantum wires
near the diffusive regime. We consider the asymptotic behavior in the limit
where the number of channels and the length of the wire in the units of the
mean free path are large but the bare conductance is fixed. A recursion
equation unifying the descriptions of the standard and Bogoliubov--de Gennes
(BdG) symmetry classes is presented. We give values and come up with a novel
scaling form for the higher-order conductance cumulants. In the BdG wires, in
the presence of time-reversal symmetry, for the cumulants higher than the
second it is found that there may be only contributions which depend
nonanalytically on the wire length. This indicates that diagrammatic or
semiclassical pictures do not adequately describe higher-order spectral
correlations. Moreover, we obtain the weak-localization corrections to
with .Comment: 7 page
Stark effect and generalized Bloch-Siegert shift in a strongly driven two-level system
A superconducting qubit was driven in an ultrastrong fashion by an
oscillatory microwave field, which was created by coupling via the nonlinear
Josephson energy. The observed Stark shifts of the `atomic' levels are so
pronounced that corrections even beyond the lowest-order Bloch-Siegert shift
are needed to properly explain the measurements. The quasienergies of the
dressed two-level system were probed by resonant absorption via a cavity, and
the results are in agreement with a calculation based on the Floquet approach.Comment: 4+ page
Ensuring effective computerised clinical decision support
As part of our series on the NICE Medicines Optimisation guidance,1this article discusses the section of the guidance concerning computerised clinical decision support and how clinicians working in general practice can ensure its effectiveness and safety at the point of prescribing medicines
Synthesis, Stability and Relaxivity of TEEPO-Met : An Organic Radical as a Potential Tumour Targeting Contrast Agent for Magnetic Resonance Imaging
Cancer is a widespread and life-threatening disease and its early-stage diagnosis is vital. One of the most effective, non-invasive tools in medical diagnostics is magnetic resonance imaging (MRI) with the aid of contrast agents. Contrast agents that are currently in clinical use contain metals, causing some restrictions in their use. Also, these contrast agents are mainly non-specific without any tissue targeting capabilities. Subsequently, the interest has notably increased in the research of organic, metal-free contrast agents. This study presents a new, stable organic radical, TEEPO-Met, where a radical moiety 2,2,6,6-tetraethylpiperidinoxide (TEEPO) is attached to an amino acid, methionine (Met), as a potentially tumour-targeting moiety. We describe the synthesis, stability assessment with electron paramagnetic resonance (EPR) spectroscopy and relaxation enhancement abilities by an in vitro nuclear magnetic resonance (NMR) and phantom MRI studies of TEEPO-Met. The new compound proved to be stable notably longer than the average imaging time in conditions mimicking a biological matrix. Also, it significantly reduced the relaxation times of water, making it a promising candidate as a novel tumour targeting contrast agent for MRI.Peer reviewe
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