Cytotoxic CD4+ T cells in patients with B cell chronic lymphocytic leukemia kill via a perforin-mediated pathway

Background and Objectives: B-cell chronic lymphocytic leukemia (B-CLL) is a clonal expansion of CD5+B cells that accumulate due to their uncontrolled growth and resistance to apoptosis. We have previously shown that up to 50% of blood CD4+ T cells in BCLL patients have a cytotoxicity-related CD28-CD57+ phenotype and high content of both granzyme B and perforin (PF). In this study we investigate the cytotoxic potential of these cells against autologous B-CLL cells. Design and Methods: Blood CD4+ or CD8+ T cells were positively isolated from B-CLL patients and cultured under a range of conditions with autologous purified B-CLL cells and with bispecific [anti-CD3 x anti-CD19] antibodies. Apoptosis of labeled B-CLL cells was assessed using the change of mitochondrial membrane potential with the fluorescent dye DiOC6 and confirmed by annexin V binding. Results: There was time- and dose-dependent killing of B-CLL cells by both CD8+ and CD4+ T cells and this ranged from 6.6 - 68.0% for CD4+ cells and 6.4 - 57.8% for CD8+ cells. Almost complete inhibition by concanamycin A suggests that CD4+ T cells like CD8+ T cells induced apoptosis through a perforin-mediated pathway, but not via Fas/FasL (as indicated by lack of blocking with brefeldin A), tumor necrosis factor or TRAIL. Interpretation and Conclusions: This study shows that blood CD4+PF+ T cells enriched in B-CLL patients, are able to kill autologous B-CLL cells ex vivo, through bispecific antibodies via a perforin mediated mechanism

Detection of Organic-Rich Oil Shales of the Green River Formation, Utah, with Ground-Based Imaging Spectroscopy

Oil shales contain abundant immature organic matter and are a potential unconventional petroleum resource. Prior studies have used visible/shortwave infrared imaging spectroscopy to map surface exposures of deposits from satellite and airborne platforms and image cores in the laboratory. Here, we work at an intermediate, outcrop-scale, testing the ability of field-based imaging spectroscopy to identify oil shale strata and characterize the depositional environments that led to enrichment of organic matter in sedimentary rocks within the Green River Formation, Utah, USA. The oil shale layers as well as carbonates, phyllosilicates, gypsum, hydrated silica, and ferric oxides are identified in discrete lithologic units and successfully mapped in the images, showing a transition from siliciclastic to carbonate- and organic-rich rocks consistent with previous stratigraphic studies conducted with geological fieldwork

Seven-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Power Spectra and WMAP-Derived Parameters

(Abridged) We present the angular power spectra derived from the 7-year maps and discuss the cosmological conclusions that can be inferred from WMAP data alone. The third acoustic peak in the TT spectrum is now well measured by WMAP. In the context of a flat LambdaCDM model, this improvement allows us to place tighter constraints on the matter density from WMAP data alone, and on the epoch of matter-radiation equality, The temperature-polarization (TE) spectrum is detected in the 7-year data with a significance of 20 sigma, compared to 13 sigma with the 5-year data. The low-l EE spectrum, a measure of the optical depth due to reionization, is detected at 5.5 sigma significance when averaged over l = 2-7. The BB spectrum, an important probe of gravitational waves from inflation, remains consistent with zero. The upper limit on tensor modes from polarization data alone is a factor of 2 lower with the 7-year data than it was using the 5-year data (Komatsu et al. 2010). We test the parameter recovery process for bias and find that the scalar spectral index, ns, is biased high, but only by 0.09 sigma, while the remaining parameters are biased by < 0.15 sigma. The improvement in the third peak measurement leads to tighter lower limits from WMAP on the number of relativistic degrees of freedom (e.g., neutrinos) in the early universe: Neff > 2.7 (95% CL). Also, using WMAP data alone, the primordial helium mass fraction is found to be YHe = 0.28+0.14-0.15, and with data from higher-resolution CMB experiments included, we now establish the existence of pre-stellar helium at > 3 sigma (Komatsu et al. 2010).Comment: 22 pages, 14 figures, version accepted to Astrophysical Journal Supplement Series, added high-l EE detection, consolidated parameter recovery simulation

Field Scanner Design for MUSTANG of the Green Bank Telescope

MUSTANG is a bolometer camera for the Green Bank Telescope (GBT) working at a frequency of 90 GHz. The detector has a field of view of 40 arcseconds. To cancel out random emission change from atmosphere and other sources, requires a fast scanning reflecting system with a few arcminute ranges. In this paper, the aberrations of an off-axis system are reviewed. The condition for an optimized system is provided. In an optimized system, as additional image transfer mirrors are introduced, new aberrations of the off-axis system may be reintroduced, resulting in a limited field of view. In this paper, different scanning mirror arrangements for the GBT system are analyzed through the ray tracing analysis. These include using the subreflector as the scanning mirror, chopping a flat mirror and transferring image with an ellipse mirror, and chopping a flat mirror and transferring image with a pair of face-to-face paraboloid mirrors. The system analysis shows that chopping a flat mirror and using a well aligned pair of paraboloids can generate the required field of view for the MUSTUNG detector system, while other systems all suffer from larger off-axis aberrations added by the system modification. The spot diagrams of the well aligned pair of paraboloids produced is only about one Airy disk size within a scanning angle of about 3 arcmin.Comment: 7 pages, 9 figure

Detection and discrimination of cosmological non-Gaussian signatures by multi-scale methods

Recent Cosmic Microwave Background (CMB) observations indicate that the temperature anisotropies arise from quantum fluctuations in the inflationary scenario. In the simplest inflationary models, the distribution of CMB temperature fluctuations should be Gaussian. However, non-Gaussian signatures can be present. They might have different origins and thus different statistical and morphological characteristics. In this context and motivated by recent and future CMB experiments, we search for, and discriminate between, different non-Gaussian signatures. We analyse simulated maps of three cosmological sources of temperature anisotropies: Gaussian distributed CMB anisotropies from inflation, temperature fluctuations from cosmic strings and anisotropies due to the kinetic Sunyaev-Zel'dovich (SZ) effect both showing a non-Gaussian character. We use different multi-scale methods, namely, wavelet, ridgelet and curvelet transforms. The sensitivity and the discriminating power of the methods is evaluated using simulated data sets. We find that the bi-orthogonal wavelet transform is the most powerful for the detection of non-Gaussian signatures and that the curvelet and ridgelet transforms characterise quite precisely and exclusively the cosmic strings. They allow us thus to detect them in a mixture of CMB + SZ + cosmic strings. We show that not one method only should be applied to understand non-Gaussianity but rather a set of different robust and complementary methods should be used.Comment: Accepted for publication in A&A. Paper with high resolution figures can be found at http://jstarck.free.fr/cmb03.pd

Vertical cavity lasers for optical interconnects

Vertical-cavity surface-emitting lasers are generating much interest due to their geometric suitability for two-dimensional array fabrication and their potential for achieving ultra-low thresholds. Here we report on optically- and electrically-pumped microlaser devices. having transverse dimensions of a few microns and active material lengths of a few hundred A. The very small volumes are a key factor in achieving low thresholds. So far however surface recombination has prevented us from achieving thresholds much below 1 mA

A Review of the Properties of Nb3Sn and Their Variation with A15 Composition, Morphology and Strain State

This article gives an overview of the available literature on simplified, well defined (quasi-)homogeneous laboratory samples. After more than 50 years of research on superconductivity in Nb3Sn, a significant amount of results are available, but these are scattered over a multitude of publications. Two reviews exist on the basic properties of A15 materials in general, but no specific review for Nb3Sn is available. This article is intended to provide such an overview. It starts with a basic description of the Niobium-Tin intermetallic. After this it maps the influence of Sn content on the the electron-phonon interaction strength and on the field-temperature phase boundary. The literature on the influence of Cu, Ti and Ta additions will then be briefly summarized. This is followed by a review on the effects of grain size and strain. The article is concluded with a summary of the main results.Comment: Invited Topical Review for Superconductor, Science and Technology. Provisionally scheduled for July 200

Effects of Smart Position Only (SPOT) Tag Deployment on White Sharks Carcharodon carcharias in South Africa

We present 15 individual cases of sub-adult white sharks that were SPOT tagged in South Africa from 2003–2004 and have been re-sighted as recently as 2011. Our observations suggest SPOT tags can cause permanent cosmetic and structural damage to white shark dorsal fins depending on the duration of tag attachment. SPOT tags that detached within 12–24 months did not cause long term damage to the dorsal fin other than pigmentation scarring. Within 12 months of deployment, tag fouling can occur. After 24 months of deployment permanent damage to the dorsal fin occurred. A shark survived this prolonged attachment and there seems little compromise on the animal's long term survival and resultant body growth. This is the first investigation detailing the long term effects of SPOT deployment on the dorsal fin of white sharks