69 research outputs found

    Tunable Supercurrent Through Semiconductor Nanowires

    Full text link
    Nanoscale superconductor-semiconductor hybrid devices are assembled from InAs semiconductor nanowires individually contacted by aluminum-based superconductor electrodes. Below 1 K, the high transparency of the contacts gives rise to proximity-induced superconductivity. The nanowires form superconducting weak links operating as mesoscopic Josephson junctions with electrically tunable coupling. The supercurrent can be switched on/off by a gate voltage acting on the electron density in the nanowire. A variation in gate voltage induces universal fluctuations in the normal-state conductance which are clearly correlated to critical current fluctuations. The ac Josephson effect gives rise to Shapiro steps in the voltage-current characteristic under microwave irradiation.Comment: 9 pages, 3 figure

    Prevalence of Coxielle Burnetii anbitodies in Danish Dairy herds

    Get PDF
    <p>Abstract</p> <p>During recent years in Denmark higher rates of antibodies to <it>Coxiella burnetii </it>have been detected in animals and humans than previously reported. A study based on bulk tank milk samples from 100 randomly selected dairy herds was performed to estimate the prevalence and geographical distribution of antibody positive dairy herds. Using the CHEKIT Q-Fever Antibody ELISA Test Kit (IDEXX), the study demonstrated a prevalence of 59% antibody positive herds, 11% antibody intermediate herds and 30% antibody negative herds based on the instructions provided by the manufacturer. The geographical distribution does not indicate a relationship between the regional density of dairy farms and the prevalence of antibody positive dairy farms. The result supports the hypothesis of an increase in the prevalence of positive dairy herds compared to previous years.</p

    Intermittent intravenous paracetamol versus continuous morphine in infants undergoing cardiothoracic surgery:a multi-center randomized controlled trial

    Get PDF
    Background: To determine whether intermittent intravenous (IV) paracetamol as primary analgesic would significantly reduce morphine consumption in children aged 0–3 years after cardiac surgery with cardiopulmonary bypass. Methods: Multi-center, randomized, double-blinded, controlled trial in four level-3 Pediatric Intensive Care Units (PICU) in the Netherlands and Belgium. Inclusion period; March 2016–July 2020. Children aged 0–3 years, undergoing cardiac surgery with cardiopulmonary bypass were eligible. Patients were randomized to continuous morphine or intermittent IV paracetamol as primary analgesic after a loading dose of 100 mcg/kg morphine was administered at the end of surgery. Rescue morphine was given if numeric rating scale (NRS) pain scores exceeded predetermined cutoff values. Primary outcome was median weight-adjusted cumulative morphine dose in mcg/kg in the first 48 h postoperative. For the comparison of the primary outcome between groups, the nonparametric Van Elteren test with stratification by center was used. For comparison of the proportion of patients with one or more NRS pain scores of 4 and higher between the two groups, a non-inferiority analysis was performed using a non-inferiority margin of 20%. Results:In total, 828 were screened and finally 208 patients were included; parents of 315 patients did not give consent and 305 were excluded for various reasons. Fourteen of the enrolled 208 children were withdrawn from the study before start of study medication leaving 194 patients for final analysis. One hundred and two patients received intermittent IV paracetamol, 106 received continuous morphine. The median weight-adjusted cumulative morphine consumption in the first 48 h postoperative in the IV paracetamol group was 5 times lower (79%) than that in the morphine group (median, 145.0 (IQR, 115.0–432.5) mcg/kg vs 692.6 (IQR, 532.7–856.1) mcg/kg; P &lt; 0.001). The rescue morphine consumption was similar between the groups (p = 0.38). Non-inferiority of IV paracetamol administration in terms of NRS pain scores was proven; difference in proportion − 3.1% (95% CI − 16.6–10.3%). Conclusions: In children aged 0–3 years undergoing cardiac surgery, use of intermittent IV paracetamol reduces the median weight-adjusted cumulative morphine consumption in the first 48 h after surgery by 79% with equal pain relief showing equipoise for IV paracetamol as primary analgesic. Trial Registration Clinicaltrials.gov, Identifier: NCT05853263; EudraCT Number: 2015-001835-20.</p

    Generic nano-imprint process for fabrication of nanowire arrays

    Full text link
    A generic process has been developed to grow nearly defect free arrays of (heterostructured) InP and GaP nanowires. Soft nanoimprint lithography has been used to pattern gold particle arrays on full 2 inch substrates. After lift-off organic residues remain on the surface, which induce the growth of additional undesired nanowires. We show that cleaning of the samples before growth with piranha solution in combination with a thermal anneal at 550 C for InP and 700 C for GaP results in uniform nanowire arrays with 1% variation in nanowire length, and without undesired extra nanowires. Our chemical cleaning procedure is applicable to other lithographic techniques such as e-beam lithography, and therefore represents a generic process.Comment: 12 pages, 4 figures, 2 table

    Intravenous morphine versus intravenous paracetamol after cardiac surgery in neonates and infants

    Get PDF
    Background: Morphine is worldwide the analgesic of first choice after cardiac surgery in children. Morphine has unwanted hemodynamic and respiratory side effects. Therefore, post-cardiac surgery patients may potentially benefit from a non-opioid drug for pain relief. A previous study has shown that intravenous (IV) paracetamol is effective and opioid-sparing in children after major non-cardiac surgery. The aim of the study is to test the hypothesis that intermittent IV paracetamol administration in children after cardiac surgery will result in a reduction of at least 30% of the cumulative morphine requirement. Methods: This is a prospective, multi-center, randomized controlled trial at four level-3 pediatric intensive care units (ICUs) in the Netherlands and Belgium. Children who are 0-36months old will be randomly assigned to receive either intermittent IV paracetamol or continuous IV morphine up to 48h post-operatively. Morphine will be available as rescue medication for both groups. Validated pain and sedation assessment tools will be used to monitor patients. The sample size (n=208, 104 per arm) was calculated in order to detect a 30% reduction in morphine dose; two-sided significance level was 5% and power was 95%. Discussion: This study will focus on the reduction, or replacement, of morphine by IV paracetamol in children (0-36months old) after cardiac surgery. The results of this study will form the basis of a new pain management algorithm and will be implemented at the participating ICUs, resulting in an evidence-based guideline on post-operative pain after cardiac surgery in infants who are 0-36months old
    • …
    corecore