184 research outputs found

    Solar plasma experiment

    Get PDF
    Solar plasma experiment by Mariner IV space prob

    Ultrahigh Purcell factors and Lamb shifts using slow-light metamaterial waveguides

    Full text link
    Employing a medium-dependent quantum optics formalism and a Green function solution of Maxwell's equations, we study the enhanced spontaneous emission factors (Purcell factors) and Lamb shifts from a quantum dot or atom near the surface of a %embedded in a slow-light metamaterial waveguide. Purcell factors of approximately 250 and 100 are found at optical frequencies for p−p-polarized and s−s-polarized dipoles respectively placed 28\thinspace nm (0.02\thinspace λ0\lambda_{0}) above the slab surface, including a realistic metamaterial loss factor of γ/2π=2THz\gamma /2\pi =2 \mathrm{THz}. For smaller loss values, we demonstrate that the slow-light regime of odd metamaterial waveguide propagation modes can be observed and related to distinct resonances in the Purcell factors. Correspondingly, we predict unusually large and rich Lamb shifts of approximately -1 GHz to -6 GHz for a dipole moment of 50 Debye. We also make a direct calculation of the far field emission spectrum, which contains direct measurable access to these enhanced Purcell factors and Lamb shifts

    Study of Sexual Functioning Determinants in Breast Cancer Survivors

    Full text link
    Our goal was to identify the treatment, personal, interpersonal, and hormonal (testosterone) factors in breast cancer survivors (BCSs) that determine sexual dysfunction. The treatment variables studied were type of surgery, chemotherapy, radiation, and tamoxifen. The personal, interpersonal, and physiologic factors were depression, body image, age, relationship distress, and testosterone levels. A sample of 55 female breast cancer survivors seen for routine follow-up appointments from July 2002 to September 2002 were recruited to complete the Female Sexual Functioning Index (FSFI), Hamilton Depression Inventory (HDI), Body Image Survey (BIS), Marital Satisfaction Inventory-Revised (MSI-R), a demographic questionnaire, and have a serum testosterone level drawn. The average time since diagnosis was 4.4 years (SD 3.4 years). No associations were found between the type of cancer treatment, hormonal levels, and sexual functioning. BCS sexual functioning was significantly poorer than published normal controls in all areas but desire. The BCSs’ level of relationship distress was the most significant variable affecting arousal, orgasm, lubrication, satisfaction, and sexual pain. Depression and having traditional role preferences were the most important determinants of lower sexual desire. BCSs on antidepressants had higher levels of arousal and orgasm dysfunction. Women who were older had significantly more concerns about vaginal lubrication and pain. Relationship concerns, depression, and age are important influences in the development of BCS sexual dysfunction. The relationship of testosterone and sexual dysfunction needs further study with larger samples and more accurate assay techniques.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72034/1/j.1075-122X.2005.00131.x.pd

    Midday measurements of leaf water potential and stomatal conductance are highly correlated with daily water use of Thompson Seedless grapevines

    Get PDF
    A study was conducted to determine the relationship between midday measurements of vine water status and daily water use of grapevines measured with a weighing lysimeter. Water applications to the vines were terminated on August 24th for 9 days and again on September 14th for 22 days. Daily water use of the vines in the lysimeter (ETLYS) was approximately 40 L vine−1 (5.3 mm) prior to turning the pump off, and it decreased to 22.3 L vine−1 by September 2nd. Pre-dawn leaf water potential (ΨPD) and midday Ψl on August 24th were −0.075 and −0.76 MPa, respectively, with midday Ψl decreasing to −1.28 MPa on September 2nd. Leaf g s decreased from ~500 to ~200 mmol m−2 s−1 during the two dry-down periods. Midday measurements of g s and Ψl were significantly correlated with one another (r = 0.96) and both with ETLYS/ETo (r = ~0.9). The decreases in Ψl, g s, and ETLYS/ETo in this study were also a linear function of the decrease in volumetric soil water content. The results indicate that even modest water stress can greatly reduce grapevine water use and that short-term measures of vine water status taken at midday are a reflection of daily grapevine water us

    Determination of migration monomer styrene from GPPS (general purpose polystyrene) and HIPS (high impact polystyrene) cups to hot drinks

    Get PDF
    In this study, 162 samples were analysed for monomer styrene content with using high performance liquid chromatography (HPLC) method in hot tea, milk, cocoa milk. The monomer styrene content, expressed in μg/l of drink and the level of migration of styrene monomer were varied from 0.61 to 8.15 for hot tea, from 0.65 to 8.30 for hot milk, from 0.71 to 8.65 for hot cocoa milk in GPPS (general purpose polystyrene), from 0.48 to 6.85 for hot tea, from 0.61 to 7.65 for hot milk, from 0.72 to 7.78 for hot cocoa milk in HIPS (high performance polystyrene) cups in different temperatures and times. The estimated limit of detection of (HPLC) method for all samples was 0.001 mg/kg. There is linear regression for styrene monomer from 1 to 10 ng/ml. Several samples spiked with a known amount of styrene monomer. The results of the recovery in study for styrene monomer were determinate to be mean, 96.1 ± 1.92 to 99.7 ± 1.15%. The results of this study indicate that styrene monomer from polystyrene disposable into hot and fat drinks was migrated and this migration was highly dependent on fat content and temperature of drinks. The derived concentration of styrene monomer in this study was above the EPA (Environmental protection agency) recommended level, especially in MCLG (Maximum contaminant level goal) standard. More study is needed to further elucidate this finding

    "An infinitude of Possible Worlds": towards a research method for hypertext fiction

    Get PDF
    While the investigation of creative writing as a research method is gathering apace, little work has been done into the specific case of hypertext fiction (fiction written through a digital medium). This paper argues that, while there remain certain similarities between paper-based and digital texts, fundamental differences in design and construction remain. If hypertext fictions are to be successfully understood, then the role and purpose of the digital writer needs to be more fully analysed as part of the creative process. This paper argues that Possible Worlds Theory offers a way forward. With its focus on the ontological structures created by hypertext fiction, Possible World Theory actively embraces narrative indeterminacy and ontological changeability. In this sense the method provides a structured means by which the creative manipulation of the unique affordances of a digital medium by a writer can be theorised

    Racism as a determinant of health: a systematic review and meta-analysis

    Get PDF
    Despite a growing body of epidemiological evidence in recent years documenting the health impacts of racism, the cumulative evidence base has yet to be synthesized in a comprehensive meta-analysis focused specifically on racism as a determinant of health. This meta-analysis reviewed the literature focusing on the relationship between reported racism and mental and physical health outcomes. Data from 293 studies reported in 333 articles published between 1983 and 2013, and conducted predominately in the U.S., were analysed using random effects models and mean weighted effect sizes. Racism was associated with poorer mental health (negative mental health: r = -.23, 95% CI [-.24,-.21], k = 227; positive mental health: r = -.13, 95% CI [-.16,-.10], k = 113), including depression, anxiety, psychological stress and various other outcomes. Racism was also associated with poorer general health (r = -.13 (95% CI [-.18,-.09], k = 30), and poorer physical health (r = -.09, 95% CI [-.12,-.06], k = 50). Moderation effects were found for some outcomes with regard to study and exposure characteristics. Effect sizes of racism on mental health were stronger in cross-sectional compared with longitudinal data and in non-representative samples compared with representative samples. Age, sex, birthplace and education level did not moderate the effects of racism on health. Ethnicity significantly moderated the effect of racism on negative mental health and physical health: the association between racism and negative mental health was significantly stronger for Asian American and Latino(a) American participants compared with African American participants, and the association between racism and physical health was significantly stronger for Latino(a) American participants compared with African American participants.<br /
    • …
    corecore