Sinusoidal-pressure generator for testing dynamic pressure probes

Generator can produce sinusoidal pressures at frequencies from 300 to 5000 Hz and peak-to-peak amplitudes up to 5.6 lbs/sq in. Amplitude and phase-angle measurements made at various frequencies are compared with measurements from a piezoelectric transducer mounted flush with the resonant tube wall

Asymptotic Expansions for Stationary Distributions of Perturbed Semi-Markov Processes

New algorithms for computing of asymptotic expansions for stationary distributions of nonlinearly perturbed semi-Markov processes are presented. The algorithms are based on special techniques of sequential phase space reduction, which can be applied to processes with asymptotically coupled and uncoupled finite phase spaces.Comment: 83 page

Quantification of myelin loss in frontal lobe white matter in vascular dementia, Alzheimer's disease, and dementia with Lewy bodies

The aim of this study was to characterize myelin loss as one of the features of white matter abnormalities across three common dementing disorders. We evaluated post-mortem brain tissue from frontal and temporal lobes from 20 vascular dementia (VaD), 19 Alzheimer’s disease (AD) and 31 dementia with Lewy bodies (DLB) cases and 12 comparable age controls. Images of sections stained with conventional luxol fast blue were analysed to estimate myelin attenuation by optical density. Serial adjacent sections were then immunostained for degraded myelin basic protein (dMBP) and the mean percentage area containing dMBP (%dMBP) was determined as an indicator of myelin degeneration. We further assessed the relationship between dMBP and glutathione S-transferase (a marker of mature oligodendrocytes) immunoreactivities. Pathological diagnosis significantly affected the frontal but not temporal lobe myelin attenuation: myelin density was most reduced in VaD compared to AD and DLB, which still significantly exhibited lower myelin density compared to ageing controls. Consistent with this, the degree of myelin loss was correlated with greater %dMBP, with the highest %dMBP in VaD compared to the other groups. The %dMBP was inversely correlated with the mean size of oligodendrocytes in VaD, whereas it was positively correlated with their density in AD. A two-tier regression model analysis confirmed that the type of disorder (VaD or AD) determines the relationship between %dMBP and the size or density of oligodendrocytes across the cases. Our findings, attested by the use of three markers, suggest that myelin loss may evolve in parallel with shrunken oligodendrocytes in VaD but their increased density in AD, highlighting partially different mechanisms are associated with myelin degeneration, which could originate from hypoxic–ischaemic damage to oligodendrocytes in VaD whereas secondary to axonal degeneration in AD

A Diamond Nanowire Single Photon Antenna

The development of a robust light source that emits one photon at a time is an outstanding challenge in quantum science and technology. Here, at the transition from many to single photon optical communication systems, fully quantum mechanical effects may be utilized to achieve new capabilities, most notably perfectly secure communication via quantum cryptography. Practical implementations place stringent requirements on the device properties, including stable photon generation, room temperature operation, and efficient extraction of many photons. Single photon light emitting devices based on fluorescent dye molecules, quantum dots, and carbon nanotube material systems have all been explored, but none have simultaneously demonstrated all criteria. Here, we describe the design, fabrication, and characterization of a bright source of single photons consisting of an individual Nitrogen-vacancy color center (NV center) in a diamond nanowire operating in ambient conditions. The nanowire plays a positive role in increasing the number of single photons collected from the NV center by an order of magnitude over devices based on bulk diamond crystals, and allows operation at an order of magnitude lower power levels. This result enables a new class of nanostructured diamond devices for room temperature photonic and quantum information processing applications, and will also impact fields as diverse as biological and chemical sensing, opto-mechanics, and scanning-probe microscopy.Comment: 16 pages, 4 figures, v2: Includes improved reference list; modified figure 1 to show a large array of NW and FDTD simulation of field profile; direct experimental comparsion of several bulk/NW devices in figure

Safety and Immunogenicity Following Administration of a Live, Attenuated Monovalent 2009 H1N1 Influenza Vaccine to Children and Adults in Two Randomized Controlled Trials

BACKGROUND: The safety, tolerability, and immunogenicity of a monovalent intranasal 2009 A/H1N1 live attenuated influenza vaccine (LAIV) were evaluated in children and adults. METHODS/PRINCIPAL FINDINGS: Two randomized, double-blind, placebo-controlled studies were completed in children (2-17 y) and adults (18-49 y). Subjects were assigned 4:1 to receive 2 doses of H1N1 LAIV or placebo 28 days apart. The primary safety endpoint was fever ≥38.3°C during days 1-8 after the first dose; the primary immunogenicity endpoint was the proportion of subjects experiencing a postdose seroresponse. Solicited symptoms and adverse events were recorded for 14 days after each dose and safety data were collected for 180 days post-final dose. In total, 326 children (H1N1 LAIV, n = 261; placebo, n = 65) and 300 adults (H1N1 LAIV, n = 240; placebo, n = 60) were enrolled. After dose 1, fever ≥38.3°C occurred in 4 (1.5%) pediatric vaccine recipients and 1 (1.5%) placebo recipient (rate difference, 0%; 95% CI: -6.4%, 3.1%). No adults experienced fever following dose 1. Seroresponse rates in children (H1N1 LAIV vs. placebo) were 11.1% vs. 6.3% after dose 1 (rate difference, 4.8%; 95% CI: -9.6%, 13.8%) and 32.0% vs. 14.5% after dose 2 (rate difference, 17.5%; 95% CI: 5.5%, 27.1%). Seroresponse rates in adults were 6.1% vs. 0% (rate difference, 6.1%; 95% CI: -5.6%, 12.6%) and 14.9% vs. 5.6% (rate difference, 9.3%; 95% CI: -0.8%, 16.3%) after dose 1 and dose 2, respectively. Solicited symptoms after dose 1 (H1N1 LAIV vs. placebo) occurred in 37.5% vs. 32.3% of children and 41.7% vs. 31.7% of adults. Solicited symptoms occurred less frequently after dose 2 in adults and children. No vaccine-related serious adverse events occurred. CONCLUSIONS/SIGNIFICANCE: In subjects aged 2 to 49 years, two doses of H1N1 LAIV have a safety and immunogenicity profile similar to other previously studied and efficacious formulations of seasonal trivalent LAIV. TRIAL REGISTRATION: ClinicalTrials.gov NCT00946101, NCT00945893

Current concepts of polymicrogyria

Polymicrogyria is one of the most common malformations of cortical development. It has been known for many years and its clinical and MRI manifestations are well described. Recent advances in imaging, however, have revealed that polymicrogyria has many different appearances on MR imaging, suggesting that is may be a more heterogeneous malformation than previously suspected. The clinical and imaging heterogeneity of polymicrogyria is explored in this review

Anthrax outbreak in a Swedish beef cattle herd - 1st case in 27 years: Case report

After 27 years with no detected cases, an outbreak of anthrax occurred in a beef cattle herd in the south of Sweden. The outbreak was unusual as it occurred in winter, in animals not exposed to meat-and-bone meal, in a non-endemic country