Toward a Clean Sample of Ultra-Luminous X-ray Sources

CONTEXT. Observational follow-up programmes for the characterization of ultra-luminous X-ray sources (ULXs) require the construction of clean samples of such sources in which the contamination by foreground/background sources is minimum. AIMS. In this article we calculate the degree of foreground/background contaminants among the ULX sample candidates in the Colbert & Ptak (2002) catalogue and compare these computations with available spectroscopical identifications. METHODS. We use statistics based on known densities of X-ray sources and AGN/QSOs selected in the optical. The analysis is done individually for each parent galaxy. The existing identifications of the optical counterparts are compiled from the literature. RESULTS. More than a half of the ULXs, within twice the distance of the major axis of the 25 mag/arcsec$^2$ isophote from RC3 nearby galaxies and with X-ray luminosities $L_X$[2-10 keV] $\ge 10^{39}$ erg/s, are expected to be high redshift background QSOs. A list of 25 objects (clean sample) confirmed to be real ULXs or to have a low probability of being contaminant foreground/background objects is provided.Comment: 9 pages, accepted in A&

X-ray Constraints on the Lyman-Alpha Escape Fraction

We have coadded X-ray flux of all known Lyman Alpha Emitters (LAEs) in the 4 Msec Chandra Deep Field South (CDF-S) region, to place sensitive upper limits on the average unobscured star-formation rate (SFR_X) in these galaxies. A very small fraction of Lyman-Alpha galaxies in the field are individually detected in the X-rays, implying a low fraction of AGN activity. After excluding the few X-ray detected LAEs, we stack the undetected LAEs located in the 4 Ms CDF-S data and 250 ks Extended CDF-S (ECDFS) data, and compute a 1-\sigma upper limit on SFR_X < 14, 28, 28, 140, 440, 880 M_{\sun} yr$^{-1}$ for LAEs located at z = 2.1, 3.1, 3.2, 4.5, 5.7 and 6.5, respectively. The upper limit of SFR_X in LAEs can be then be compared to SFR$_{Ly\alpha}$ derived from Lyman-Alpha line and thus can constrain on the Lyman-Alpha escape fraction ($f^{Esc}_{Ly\alpha}$). We derive a lower limit on f(Lyman-Alpha Escape) > 14% (84 % confidence level, 1-\sigma lower limit) for LAEs at redshift z ~ 2.1 and z ~ 3.1-3.2. At z > 4, the current LAE samples are not of sufficient size to constrain SFR_X well. By averaging all the LAEs at z> 2, the X-ray non-detection constrains f(Lyman-Alpha Escape) > 17% (84 % confidence level, 1-\sigma lower limit), and rejects f(Lyman-Alpha Escape) < 5.7% at the 99.87% confidence level from 2.1 < z < 6.5.Comment: 11 pages, 3 tables, 3 figures, ApJ accepte

Life without the Movius Line: The structure of the East and Southeast Asian Early Palaeolithic

© 2015 Elsevier Ltd and INQUA.The starting point of this paper is that the Movius Line is no longer an appropriate way of studying the Early Palaeolithic of East and Southeast Asia, and should be disregarded. Instead, it is argued that the Early Palaeolithic of East and Southeast Asia needs to be seen as comparable to that in the rest of Eurasia, rather than the product of an isolated backwater. Contra Movius, East Asia was not isolated throughout the entire Early and Middle Pleistocene, but open to immigration during interglacials, as is indicated by its fossil hominin record. As in Europe and Southwest Asia, both bifacial and non-biface assemblages are present in China and Korea, thus indicating the presence of an Acheulean component, although the lack of agreement over how the Acheulean should be defined creates difficulties in establishing its extent in Southeast Asia. Regarding non-biface assemblages, Zhoukoudian was an unfortunate choice of an East Asian site that lacked bifaces, as bifaces are also rare or absent in a number of caves in Southwest Asia and Europe. Additionally, the absence of bifaces in some sites is not convincingly demonstrated because of the small size of the lithic assemblage. Finally, the simple flake industries in Southeast Asia are likely contemporary with Upper Pleistocene, Middle Palaeolithic and microlithic assemblages in India rather than with Middle Pleistocene, Acheulean assemblages, as proposed by Movius

Can cognitive insight predict symptom remission in a first episode psychosis cohort?

BACKGROUND: The outcome of first episode psychosis (FEP) is highly variable and difficult to predict. Cognitive insight measured at illness onset has previously been found to predict psychopathology 12-months later. The aims of this study were to examine whether the prospective relationship between cognitive insight and symptom severity is evident at four-years following FEP and to examine some psychological correlates of cognitive insight. METHODS: FEP participants (n = 90) completed the Beck Cognitive Insight Scale (BCIS) at illness onset, and associations between BCIS scores with symptom severity outcomes (4-years after FEP) were assessed. The BCIS scales (self-reflectiveness and self-certainty) were examined as a composite score, and individually compared to other cognitive measures (IQ and jumping to conclusions (JTC) bias). RESULTS: Regression analyses revealed that the cognitive insight composite did not predict 4-year symptom remission in this study while the self-reflection subscale of the BCIS predicted severity of symptoms at 4-years. Self-certainty items of the BCIS were not associated with symptom severity. Significant correlations between the JTC bias, self-certainty and IQ were found, but self-reflection did not correlate with these other cognitive measures. CONCLUSIONS: Self-reflective capacity is a more relevant and independent cognitive construct than self-certainty for predicting prospective symptom severity in psychosis. Improving self-reflection may be a useful target for early intervention research

Do sociodemographic factors affect beverages offered to WIC toddlers?

Includes bibliographical references (pages [32]-34).M.S. (Master of Science

I\u27m a slave to you, don\u27t you want the heart I gave [first line of chorus]

Performers: Claudette ColbertPiano, Voice and Chord