2,083 research outputs found

    Low-noise 0.8-0.96- and 0.96-1.12-THz superconductor-insulator-superconductor mixers for the Herschel Space Observatory

    Get PDF
    Heterodyne mixers incorporating Nb SIS junctions and NbTiN-SiO/sub 2/-Al microstrip tuning circuits offer the lowest reported receiver noise temperatures to date in the 0.8-0.96- and 0.96-1.12-THz frequency bands. In particular, improvements in the quality of the NbTiN ground plane of the SIS devices' on-chip microstrip tuning circuits have yielded significant improvements in the sensitivity of the 0.96-1.12-THz mixers relative to previously presented results. Additionally, an optimized RF design incorporating a reduced-height waveguide and suspended stripline RF choke filter offers significantly larger operating bandwidths than were obtained with mixers that incorporated full-height waveguides near 1 THz. Finally, the impact of junction current density and quality on the performance of the 0.8-0.96-THz mixers is discussed and compared with measured mixer sensitivities, as are the relative sensitivities of the 0.8-0.96- and 0.96-1.12-THz mixers

    The Formation and Coarsening of the Concertina Pattern

    Full text link
    The concertina is a magnetization pattern in elongated thin-film elements of a soft material. It is a ubiquitous domain pattern that occurs in the process of magnetization reversal in direction of the long axis of the small element. Van den Berg argued that this pattern grows out of the flux closure domains as the external field is reduced. Based on experimental observations and theory, we argue that in sufficiently elongated thin-film elements, the concertina pattern rather bifurcates from an oscillatory buckling mode. Using a reduced model derived by asymptotic analysis and investigated by numerical simulation, we quantitatively predict the average period of the concertina pattern and qualitatively predict its hysteresis. In particular, we argue that the experimentally observed coarsening of the concertina pattern is due to secondary bifurcations related to an Eckhaus instability. We also link the concertina pattern to the magnetization ripple and discuss the effect of a weak (crystalline or induced) anisotropy

    Aberrant STYK1 expression in ovarian cancer tissues and cell lines

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Overexpression of <it>STYK1</it>, a putative serine/threonine and tyrosine receptor protein kinase has been shown to confer tumorigenicity and metastatic potential to normal cells injected into nude mice. Mutation of a tyrosine residue in the catalytic STYK1 domain attenuates the tumorigenic potential of tumor cells <it>in vivo</it>, collectively, suggesting an oncogenic role for STYK1.</p> <p>Methods</p> <p>To investigate the role of STYK1 expression in ovarian cancer, a panel of normal, benign, and ovarian cancer tissues was evaluated for STYK1 immunoreactivity using STYK1 antibodies. In addition, mRNA levels were measured by reverse transcription PCR and real-time PCR of estrogen receptors, GPR30 and STYK1 following treatment of ovarian cell lines with estrogen or G1, a GPR30 agonist, as well as western analysis.</p> <p>Results</p> <p>Our data showed higher expression of STYK1 in cancer tissues versus normal or benign. Only normal or benign, and one cancer tissue were STYK1-negative. Moreover, benign and ovarian cancer cell lines expressed <it>STYK1 </it>as determined by RT-PCR. Estradiol treatment of these cells resulted in up- and down-regulation of <it>STYK1 </it>despite estrogen receptor status; whereas G-1, a GPR30-specific agonist, increased STYK1 mRNA levels higher than that of estradiol.</p> <p>Conclusion</p> <p>We conclude that <it>STYK1 </it>is expressed in ovarian cancer and is regulated by estrogen through a GPR30 hormone-signaling pathway, to the exclusion of estrogen receptor-alpha.</p

    Beauty and the Flirt: Male Physical Attractiveness and Approaches to Relationship Initiation

    Get PDF
    This multi-study investigation explored how women evaluate men’s approach strategies. In Study 1, 330 participants generated 546 verbal strategies used in courtship initiation. Strategies were rated on three dimensions that define relationships: affiliation, dominance, and explicitness. Affiliation and explicitness were related to strategy flirtatiousness. In Study 2, 361 females participated in an experiment that explored the effects of four approach strategies used by an attractive or unattractive man on conversation continuance and future interaction. Attractive men using inviting, playful, and less annoying messages were most successful. Study 3 (N = 398) replicated Study 2 using different approach strategies, and also demonstrated male attractiveness, affiliation and explicitness inform message flirtatiousness and influence courtship outcomes. Results suggest approach strategy, but not male attractiveness, influence perceived first date goals

    Capturing flow transformation processes across an uneven seabed in coarse-grained sediment gravity flow deposits

    Get PDF
    The upper part of the Jurassic stratigraphy of the Los Molles Formation corresponds to deepwater succession deposited with a regional marine transgression during the early postrift stage of the Neuquén Basin. The present study conducted in the location of Chacay Melehue (Argentina) is used to document the interactions between coarse-grained sediment gravity flows and the depositional relief of a seismic-scale mass transport complex (MTC), with metre-scale mounds and decametric protruding clasts, as an analogue for similar configurations in subsurface systems. The 60 m thick succession is exposed along a 6.5 km long oblique downdip longitudinal profile. Exposure quality permits walking out of individual beds. A total of 16 stratigraphic sections (1560 m thick) spaced between 500 m and 100 m, were logged at 1:50 and 1:25 scale. The basal datum of the studied interval is the top of a MTC and the top marker bed is an extensive sandstone bed. Two units studied correspond to very coarse to fine-grained medium-bedded sandstones with abundant pebble-sized clasts (Unit1) and three thick plurimetric distinct beds of poorly-sorted, granular to medium-grained mud-rich sandstone matrix supporting polygenic gravels (Unit2). Distinct thick extensive beds in both units are intercalated with heterolithic successions of thin to medium-bedded very coarse- to coarse-grained or fine-grained sandstones, siltstones and mudstones. The sandstone beds in Unit 1 abruptly pinchout in the proximal part of study area. They are associated with evidence of erosion, sediment bypass and transformation of subaqueous sand-bearing flows. Stratigraphically, sandstone packages in the Unit 2 are increasingly more laterally extensive upwards in the succession. Thickness variations in these beds are related to compensational stacking. The research will inform studies in the architecture of deep-water successions above an uneven seabed inherited from the top of a MTC. The detailed analysis of exhumed examples that record depositional changes in the structure of the flow can lead to the development of predictive stratigraphic models which incorporate details and complexities observed in outcrop and can be applied for the evaluation of the quality of subsurface reservoirs.Fil: Privat, Aurélia. University of Leeds; Reino UnidoFil: Hodgson, David. University of Leeds; Reino UnidoFil: Peakall, Jeffrey. University of Leeds; Reino UnidoFil: Jackson, Christopher A. L.. University of Leeds; Reino UnidoFil: Schwarz, Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigaciones Geológicas. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Investigaciones Geológicas; Argentina2016 AAPG/SEG International Convention and ExhibitionBarcelonaEspañaAmerican Association of Petroleum GeologistsSociety of Exploration Geophysicist

    The accuracy and completeness for receipt of colorectal cancer care using Veterans Health Administration administrative data.

    Get PDF
    The National Comprehensive Cancer Network and the American Society of Clinical Oncology have established guidelines for the treatment and surveillance of colorectal cancer (CRC), respectively. Considering these guidelines, an accurate and efficient method is needed to measure receipt of care

    Nitropyrene: DNA binding and adduct formation in respiratory tissues.

    Get PDF
    Binding of 1-nitro (14C)pyrene (NP) or its metabolites to cellular DNA and protein in cultures of rabbit alveolar macrophages, lung tissue, and tracheal tissue was examined. DNA binding in tracheal tissue (136 +/- 18.3 pmole NP/mg DNA) was four to five times the levels measured in either lung tissue (38 +/- 9.4 pmole NP/mg DNA) or macrophages (26 +/- 7.5 pmole NP/mg DNA). Adduct analysis of DNA isolated from lung tissue incubated with 1-nitro[H3]pyrene in vitro resulted in the identification of 2 to 5% of the NP adducts as C8-deoxyguanosine 1-aminopyrene. NP was also bound to cellular protein in tracheal tissue and lung tissue, and at a lower level in macrophages. Cocultivation of the macrophages with lung and tracheal tissue decreased the DNA binding in tracheal tissue by 45%. Following intratracheal instillation of diesel particles (5 mg) vapor-coated with 14C-NP (380 ppm, 0.085 muCi/mg) particles into rats, 5-8% of the radioactivity remained in the lungs after 20 hr. Most of the diesel particles were also deposited in the lung. Examination of DNA and protein binding in this tissue showed 5 to 12% of the pulmonary 14C bound to protein and no detectable levels of 14C bound to DNA

    Fundamental Behavior of Electric Field Enhancements in the Gaps Between Closely Spaced Nanostructures

    Full text link
    We demonstrate that the electric field enhancement that occurs in a gap between two closely spaced nanostructures, such as metallic nanoparticles, is the result of a transverse electromagnetic waveguide mode. We derive an explicit semianalytic equation for the enhancement as a function of gap size, which we show has a universal qualitative behavior in that it applies irrespective of the material or geometry of the nanostructures and even in the presence of surface plasmons. Examples of perfect electrically conducting and Ag thin-wire antennas and a dimer of Ag spheres are presented and discussed.Comment: 9 pages and 4 figure

    On a two variable class of Bernstein-Szego measures

    Full text link
    The one variable Bernstein-Szego theory for orthogonal polynomials on the real line is extended to a class of two variable measures. The polynomials orthonormal in the total degree ordering and the lexicographical ordering are constructed and their recurrence coefficients discussed.Comment: minor change

    The roles of motivation and ability in controlling the consequences of stereotype suppression

    Get PDF
    Two experiments investigated the conditions under which previously suppressed stereotypes are applied in impression formation. In Experiment 1, the extent to which a previously suppressed racial stereotype influenced subsequent impressions depended on the race of the target who was subsequently encountered. Whereas impressions of race-unspecified targets were assimilated to the stereotype following its suppression, no such effects were observed when the target belonged to the racial group whose stereotype had been initially suppressed. These results demonstrate that when perceivers are motivated to avoid stereo-typing individuals, the influence of a stereotype that has been previously activated through suppression is minimized. Experiment 2 demonstrated that these processing goals effectively reduce the impact of suppression-activated stereotypes only when perceivers have sufficient capacity to enact the goals. These results suggest that both sufficient motivation and capacity are necessary to prevent heightened stereotyping following stereotype suppression
    • …
    corecore