Direct observation of band-gap closure for a semiconducting carbon nanotube in a large parallel magnetic field

We have investigated the magnetoconductance of semiconducting carbon nanotubes (CNTs) in pulsed, parallel magnetic fields up to 60 T, and report the direct observation of the predicted band-gap closure and the reopening of the gap under variation of the applied magnetic field. We also highlight the important influence of mechanical strain on the magnetoconductance of the CNTs.Comment: 4 pages, 4 figure

Recovery of intracranial stenoses in varicella zoster virus vasculitis after long-term treatment with valacyclovir and prednisolone

BACKGROUND AND PURPOSE: Optimal treatment of intracranial stenoses in varicella zoster virus (VZV)-associated vasculitis is unknown. This study aims to evaluate the merits and potential pitfalls of a specific therapeutic strategy, initially proposed by Don Gilden in 2015. METHODS: We describe three patients with intracranial stenoses caused by VZV vasculitis successfully treated by a long-term combination of valacyclovir and prednisolone. RESULTS: All three patients were young men suffering from stroke. Only one reported a first contact to VZV in adulthood. All three presented stenoses in the intracranial part of the internal carotid artery or the proximal segments of the middle cerebral artery as well as an elevated cell count and positive VZV antibody index in cerebrospinal fluid. They received a combination therapy regimen with prednisone and valacyclovir about a minimum of one year. Intracranial stenoses improved markedly in one and almost resolved completely in the other two patients. Side effects of corticosteroid treatment occurred in two patients. CONCLUSIONS: Long-term combination treatment with prednisone and valacyclovir proved to be effective in three young men suffering from intracranial stenosis due to VZV vasculitis

Predicting Intermediate Storage Performance for Workflow Applications

Configuring a storage system to better serve an application is a challenging task complicated by a multidimensional, discrete configuration space and the high cost of space exploration (e.g., by running the application with different storage configurations). To enable selecting the best configuration in a reasonable time, we design an end-to-end performance prediction mechanism that estimates the turn-around time of an application using storage system under a given configuration. This approach focuses on a generic object-based storage system design, supports exploring the impact of optimizations targeting workflow applications (e.g., various data placement schemes) in addition to other, more traditional, configuration knobs (e.g., stripe size or replication level), and models the system operation at data-chunk and control message level. This paper presents our experience to date with designing and using this prediction mechanism. We evaluate this mechanism using micro- as well as synthetic benchmarks mimicking real workflow applications, and a real application.. A preliminary evaluation shows that we are on a good track to meet our objectives: it can scale to model a workflow application run on an entire cluster while offering an over 200x speedup factor (normalized by resource) compared to running the actual application, and can achieve, in the limited number of scenarios we study, a prediction accuracy that enables identifying the best storage system configuration

Critical temperature oscillations in magnetically coupled superconducting mesoscopic loops

We study the magnetic interaction between two superconducting concentric mesoscopic Al loops, close to the superconducting/normal phase transition. The phase boundary is measured resistively for the two-loop structure as well as for a reference single loop. In both systems Little-Parks oscillations, periodic in field are observed in the critical temperature Tc versus applied magnetic field H. In the Fourier spectrum of the Tc(H) oscillations, a weak 'low frequency' response shows up, which can be attributed to the inner loop supercurrent magnetic coupling to the flux of the outer loop. The amplitude of this effect can be tuned by varying the applied transport current.Comment: 9 pages, 7 figures, accepted for publication in Phys. Rev.

Phase transition curves for mesoscopic superconducting samples

We compute the phase transition curves for mesoscopic superconductors. Special emphasis is given to the limiting shape of the curve when the magnetic flux is large. We derive an asymptotic formula for the ground state of the Schr\"odinger equation in the presence of large applied flux. The expansion is shown to be sensitive to the smoothness of the domain. The theoretical results are compared to recent experiments.Comment: 8 pages, 1 figur

Composition of early life leukocyte populations in preterm infants with and without late-onset sepsis

Background Composition of leukocyte populations in the first month of life remains incompletely characterised, particularly in preterm infants who go on to develop late-onset sepsis (LOS). Aim To characterise and compare leukocyte populations in preterm infants with and without LOS during the first month of life. Study design Single-centre prospective observational cohort study. Participants Infants born <30 weeks gestational age (GA). Outcome measures Peripheral blood samples were collected at 1, 7, 14, 21 and 28 days of life. Leukocyte populations were characterised using 5-fluorophore-6-marker flow cytometry. Absolute leukocyte counts and frequency of total CD45+ leukocytes of each population were adjusted for GA, birth weight z-scores, sex and total leukocyte count. Results Of 119 preterm infants enrolled, 43 (36%) had confirmed or clinical LOS, with a median onset at 13 days (range 6–26). Compared to infants without LOS, the adjusted counts and frequency of neutrophils, basophils and non-cytotoxic T lymphocytes were generally lower and immature granulocytes were higher over the first month of life in infants who developed LOS. Specific time point comparisons identified lower adjusted neutrophil counts on the first day of life in those infants who developed LOS more than a week later, compared to those without LOS, albeit levels were within the normal age-adjusted range. Non-cytotoxic T lymphocyte counts and/or frequencies were lower in infants following LOS on days 21 and 28 when compared to those who did not develop LOS. Conclusion Changes in non-cytotoxic T lymphocytes occurred following LOS suggesting sepsis-induced immune suppression

Altered gene expression in human placenta after suspected preterm labour

Introduction Suspected preterm labour occurs in around 9% of pregnancies. However, almost two-thirds of women admitted for threatened preterm labour ultimately deliver at term and are considered risk-free for fetal development. Methods We examined placental and umbilical cord blood samples from preterm or term deliveries after threatened preterm labour as well as term deliveries without threatened preterm labour. We quantitatively analysed the mRNA expression of inflammatory markers (IL6, IFN?, and TNFa) and modulators of angiogenesis (FGF2, PGF, VEGFA, VEGFB, and VEGFR1). Results A total of 132 deliveries were analysed. Preterm delivery and term delivery after suspected preterm labour groups showed similar increases in TNFa expression compared with the term delivery control group in umbilical cord blood samples. Placental samples from preterm and term deliveries after suspected preterm labour exhibited significantly increased expression of TNFa and IL6 and decreased expression of IFN?. Suspected preterm labour was also associated with altered expression of angiogenic factors, although not all differences reached statistical significance. Discussion We found gene expression patterns indicative of inflammation in human placentas after suspected preterm labour regardless of whether the deliveries occurred preterm or at term. Similarly, a trend towards altered expression of angiogeneic factors was not limited to preterm birth. These findings suggest that the biological mechanisms underlying threatened preterm labour affect pregnancies independently of gestational age at birth