Mean and mean square measurements of nonstationary random processes

Mean and mean square measurements of nonstationary random processes - orthogonal function analysis and computer simulatio

A summary of methods for analyzing nonstation- ary data

Estimation of nonstationary mean values, spectral density, and correlation functions - summary of methods for analyzing nonstationary dat

Use of the ThinPrep® Imaging System does not alter the frequency of interpreting Papanicolaou tests as atypical squamous cells of undetermined significance

<p>Abstract</p> <p>Background</p> <p>Automated screening of Papanicolaou tests (Pap tests) improves the productivity of cytopathology laboratories. The ThinPrep^®Imaging System (TIS) has been widely adopted primarily for this reason for use on ThinPrep^®Pap tests (TPPT). However, TIS may also influence the interpretation of Pap tests, leading to changes in the frequency of various interpretive categories. The effect of the TIS on rates of TPPT interpretation as atypical squamous cells of undetermined significance (ASC-US) is of concern because any shift in the frequency of ASC-US will alter the sensitivity and specificity of the Pap test. We have sought to determine whether automated screening of TPPT has altered ASC-US rates in our institution when compared with manual screening (MS) of TPPT.</p> <p>Methods</p> <p>A computerized search for all ASC-US with reflex Human Papillomavirus (HPV) testing over a one-year-period (7/1/06 to 6/30/07) was conducted. Cases included both TPPT screened utilizing TIS and screened manually. HPV test results for both groups were recorded. Pertinent follow-up cervical cytology and histology results were retrieved for the period extending to 11/30/07. Automated screening was in clinical use for 10 months prior to the start of the study.</p> <p>Results</p> <p>Automated screening was performed on 23,103 TPPT, of which 977 (4.23%) were interpreted as ASC-US. Over the same period, MS was performed on 45,789 TPPT, of which 1924 (4.20%) were interpreted as ASC-US. Reflex HPV testing was positive for high risk (HR) types in 47.4% of the TIS cases and 50.2% of MS cases. Follow-up cervical dysplasia found by colposcopy was also distributed proportionally between the two groups. Cervical intraepithelial neoplasia (CIN) was found on follow-up biopsy of 20.1% of the TIS cases (5.2% CIN 2/3) and 21.2% of MS cases (5.1% CIN 2/3). None of these differences were statistically significant.</p> <p>Conclusion</p> <p>Use of the ThinPrep^®Imaging System did not appreciably change ASC-US rates or follow-up reflex HPV test results in our laboratory. This demonstrates that the benefits of automated screening may be obtained without increasing the rate of referral to colposcopy for ASC-US follow-up.</p

Starburst Galaxies

Star-formation and the Starburst phenomenon are presented with respect to a number of nearby star-forming galaxies where our understanding of the process can be calibrated. Methods of estimating star-formation rates are discussed together with the role played in the investigation of the process by multi-wavelength studies of a few selected starburst galaxies (especially the well studied galaxy M82). Our understanding of nearby systems allows us to study the star-formation history of the Universe by observing high-redshift starburst galaxies. These begin to dominate the radio source populations at centimetric wavelengths at flux densities below a few 10s of Jy. New very sensitive, high resolution telescopes in the sub-mm and radio will revolutionize our understanding of these distant star-forming systems, some of which may contain embedded AGN.Comment: 15 pages, 19 figures, To appear in the proceedings of `The 8th European VLBI Network Symposium on New Developments in VLBI Science and Technology', ed. A. Marecki et al., held in Torun, Poland, on September 26-29, 2006 (Invited Review

An evolution of the IR-Radio correlation?

Using extremely deep (rms 3.3 microJy/bm) 1.4GHz sub-arcsecond resolution MERLIN + VLA radio observations of a 8'.5 by 8'.5 field centred upon the Hubble Deep Field North, in conjunction with Spitzer 24 micron data we present an investigation of the radio-MIR correlation at very low flux densities. By stacking individual sources within these data we are able to extend the MIR-radio correlation to the extremely faint (~microJy and even sub-microJy) radio source population. Tentatively we demonstrate a small deviation from the correlation for the faintest MIR sources. We suggest that this small observed change in the gradient of the correlation is the result of a suppression of the MIR emission in faint star-forming galaxies. This deviation potentially has significant implications for using either the MIR or non-thermal radio emission as a star-formation tracer at low luminosities.Comment: To Appear in The Modern Radio Universe: From Planets to Dark Energy Conference (Oct 1-5 2007, The University of Manchester) Editors: Beswick, Diamond & Schilizz

High-z radio starbursts host obscured X-ray AGN

We use Virtual Observatory methods to investigate the association between radio and X-ray emission at high redshifts. Fifty-five of the 92 HDF(N) sources resolved by combining MERLIN+VLA data were detected by Chandra, of which 18 are hard enough and bright enough to be obscured AGN. The high-z population of microJy radio sources is dominated by starbursts an order of magnitude more active and more extended than any found at z<1 and at least a quarter of these simultaneously host highly X-ray-luminous obscured AGN.Comment: 4 pages, 2 figures, To appear in the proceedings of 'At the Edge of the Universe' (9-13 October 2006, Sintra, Portugal

An evolution of the IR-Radio correlation at very low flux densities?

In this paper we investigate the radio-MIR correlation at very low flux densities using extremely deep 1.4 GHz sub-arcsecond angular resolution MERLIN+VLA observations of a 8'.5 by 8'.5 field centred upon the Hubble Deep Field North, in conjunction with Spitzer 24micron data. From these results the MIR-radio correlation is extended to the very faint (~microJy) radio source population. Tentatively we detect a small deviation from the correlation at the faintest IR flux densities. We suggest that this small observed change in the gradient of the correlation is the result of a suppression of the MIR emission in faint star-forming galaxies. This deviation potentially has significant implications for using either the MIR or non-thermal radio emission as a star-formation tracer of very low luminosity galaxies.Comment: Accepted for publication in MNRAS, 14 pages, 9 Figures (7 colour), 2 table