Perceptual processing advantages for trauma-related visual cues in post-traumatic stress disorder

BACKGROUND: Intrusive re-experiencing in post-traumatic stress disorder (PTSD) comprises distressing sensory impressions from the trauma that seem to occur 'out of the blue'. A key question is how intrusions are triggered. One possibility is that PTSD is characterized by a processing advantage for stimuli that resemble those that accompanied the trauma, which would lead to increased detection of such cues in the environment. METHOD: We used a blurred picture identification task in a cross-sectional (n=99) and a prospective study (n=221) of trauma survivors. RESULTS: Participants with acute stress disorder (ASD) or PTSD, but not trauma survivors without these disorders, identified trauma-related pictures, but not general threat pictures, better than neutral pictures. There were no group differences in the rate of trauma-related answers to other picture categories. The relative processing advantage for trauma-related pictures correlated with re-experiencing and dissociation, and predicted PTSD at follow-up. CONCLUSIONS: A perceptual processing bias for trauma-related stimuli may contribute to the involuntary triggering of intrusive trauma memories in PTSD

A new experiment for the determination of the 18F(p,alpha) reaction rate at nova temperatures

The 18F(p,alpha) reaction was recognized as one of the most important for gamma ray astronomy in novae as it governs the early 511 keV emission. However, its rate remains largely uncertain at nova temperatures. A direct measurement of the cross section over the full range of nova energies is impossible because of its vanishing value at low energy and of the short 18F lifetime. Therefore, in order to better constrain this reaction rate, we have performed an indirect experiment taking advantage of the availability of a high purity and intense radioactive 18F beam at the Louvain La Neuve RIB facility. We present here the first results of the data analysis and discuss the consequences.Comment: Contribution to the Classical Novae Explosions conference, Sitges, Spain, 20-24 May 2002, 5 pages, 3 figure

Negative emotional stimuli reduce contextual cueing but not response times in inefficient search

In visual search, previous work has shown that negative stimuli narrow the focus of attention and speed reaction times (RTs). This paper investigates these two effects by first asking whether negative emotional stimuli narrow the focus of attention to reduce the learning of a display context in a contextual cueing task and, second, whether exposure to negative stimuli also reduces RTs in inefficient search tasks. In Experiment 1, participants viewed either negative or neutral images (faces or scenes) prior to a contextual cueing task. In a typical contextual cueing experiment, RTs are reduced if displays are repeated across the experiment compared with novel displays that are not repeated. The results showed that a smaller contextual cueing effect was obtained after participants viewed negative stimuli than when they viewed neutral stimuli. However, in contrast to previous work, overall search RTs were not faster after viewing negative stimuli (Experiments 2 to 4). The findings are discussed in terms of the impact of emotional content on visual processing and the ability to use scene context to help facilitate search

Indirect study of 19Ne states near the 18F+p threshold

The early E < 511 keV gamma-ray emission from novae depends critically on the 18F(p,a)15O reaction. Unfortunately the reaction rate of the 18F(p,a)15O reaction is still largely uncertain due to the unknown strengths of low-lying proton resonances near the 18F+p threshold which play an important role in the nova temperature regime. We report here our last results concerning the study of the d(18F,p)19F(alpha)15N transfer reaction. We show in particular that these two low-lying resonances cannot be neglected. These results are then used to perform a careful study of the remaining uncertainties associated to the 18F(p,a)15O and 18F(p,g)19Ne reaction rates.Comment: 18 pages, 8 figures. Accepted in Nuclear Physics

Population mixing and incidence of cancers in adolescents and young adults between 1990 and 2013 in Yorkshire, UK

Purpose: Epidemiological evidence suggests a role for an infectious etiology for cancers in teenagers and young adults (TYAs). We investigated this by describing associations between infection transmission using the population mixing (PM) proxy and incidence of cancers in TYAs in Yorkshire, UK. Methods: We extracted cancer cases from the Yorkshire Specialist Register of Cancer in Children and Young People from 1990 to 2013 (n = 1929). Using multivariable Poisson regression models (adjusting for effects of deprivation and population density), we investigated whether PM was associated with cancer incidence. We included population mixing–population density interaction terms to examine for differences in effects of PM in urban and rural populations. Results: Nonsignificant IRRs were observed for leukemias (IRR 1.20, 95% CI 0.91–1.59), lymphomas (IRR 1.09, 95% CI 0.90–1.32), central nervous system tumors (IRR 1.06, 95% CI 0.80–1.40) and germ cell tumors (IRR 1.14, 95% CI 0.92–1.41). The association between PM and cancer incidence did not vary in urban and rural areas. Conclusions: Study results suggest PM is not associated with incidence of cancers among TYAs. This effect does not differ between rural and urban settings

Very High Temperature Reactor (VHTR) Survey of Materials Research and Development Needs to Support Early Deployment

The VHTR reference concept is a helium-cooled, graphite moderated, thermal neutron spectrum reactor with an outlet temperature of 1000 C or higher. It is expected that the VHTR will be purchased in the future as either an electricity producing plant with a direct cycle gas turbine or a hydrogen producing (or other process heat application) plant. The process heat version of the VHTR will require that an intermediate heat exchanger (IHX) and primary gas circulator be located in an adjoining power conversion vessel. A third VHTR mission - actinide burning - can be accomplished with either the hydrogen-production or gas turbine designs. The first ''demonstration'' VHTR will produce both electricity and hydrogen using the IHX to transfer the heat to either a hydrogen production plant or the gas turbine. The plant size, reactor thermal power, and core configuration will be designed to assure passive decay heat removal without fuel damage during accidents. The fuel cycle will be a once-through very high burnup low-enriched uranium fuel cycle. The purpose of this report is to identify the materials research and development needs for the VHTR. To do this, we focused on the plant design described in Section 2, which is similar to the GT-MHR plant design (850 C core outlet temperature). For system or component designs that present significant material challenges (or far greater expense) there may be some viable design alternatives or options that can reduce development needs or allow use of available (cheaper) materials. Nevertheless, we were not able to assess those alternatives in the time allotted for this report and, to move forward with this material research and development assessment, the authors of this report felt that it was necessary to use a GT-MHR type design as the baseline design

Childhood leukaemia and population movements in France, 1990–2003

In a national study, we investigated the incidence of childhood leukaemia (CL) over a 14-year period in France in relation to several measures based on the proportion of individuals who changed address between the last two national censuses. A positive association was found with the proportion of migrants who came from a distant place. The further the migrants came, the higher was the incidence of leukaemia, particularly among children aged 0–4 years in ‘isolated' communes at the time of diagnosis (RR=1.4, 95% CI: 1.1,1.8 in the highest category of migration distance). Although the role of the population density was less obvious, a more marked association was found above a certain threshold. No association with the proportion of commuters was observed

Proceedings IMWA 2010

Abstract A research-grade passive treatment system was constructed to receive 1000 L/minute of mine water from abandoned boreholes (pH 5.95, net alkalinity 29 mg/L CaCO₃, Fe 192 mg/L, Zn 11 mg/L, Cd 17 μg/L, Pb 60 μg/L and As 64 μg/L). The 2-ha system includes an oxidation pond followed by parallel treatment trains of aerobic wetlands, vertical flow bioreactors, re-aeration ponds, and horizontal-flow limestone beds and a final polishing wetland. Final effluent waters had pH &gt;7 and contained &lt; 1 mg/L total Fe and &lt; 0.1 mg/L total Zn, with concentrations of Cd, Pb and As below detectable limits. Key Words hard rock mining, metal mining, acid mine drainage, natural treatment systems Introduction This paper describes the initial evaluation of an innovative, ecologically engineered passive system designed to treat abandoned ferruginous Pb-Zn mine waters at the Tar Creek Superfund Site, part of the historic Tri-State Mining District (TSMD) of Oklahoma, Kansas and Missouri, USA. Significant quantities of Pb and Zn were produced from the TSMD from the 1890s through the 1960s. By the early 1970s when mining ceased, two and nine million tons of Pb and Zn, respectively, had been produced During mining, large capacity dewatering operations pumped approximately 50,000 m³ d⁻¹ of water from the mines (Reed et al. 1955). Upon decline and cessation of mining, groundwater began to accumulate in the mine voids. By late 1979, metal-rich waters began to discharge via artesian pressure into Tar Creek and its tributaries. The first documented discharges of mine drainage were at a location near southeast Commerce, OK (Oklahoma Water Resources Board 1983) and were subsequently identified for passive treatment implementation Methods For this study, periodic water quality and quantity data collection efforts for the subject discharges began in 1998, with regular monthly sampling beginning in 2004 and continuing to the present. The targeted discharges have circum-neutral pH (5.96 ± 0.06), total alkalinity of 405 ± 13 mg/L as CaCO₃ and combined flow rates of up to 1000 L/minute. Metals and sulfate concentrations are elevated above expected levels and degrade the receiving waters ). Design and construction details for the passive treatment system are summarized in Sydney, NS IMWA 2010 &quot;Mine Water and Innovative Thinking&quot; Wolkersdorfer &amp; Freund Results and Discussion In the year of operation, the passive treatment system performed as designed from a water quality perspective ( Other metals of specific interest in these waters were Cd, Pb, and As. All three were removed to below detection limits (0.64, 19.5 and 22 µg/L, respectively) before the outflow of the second process units, presumably through sorptive processes. Although the vertical-flow bioreactors were designed to remove Cd and Pb as well as Zn, Cd and Pb rarely remained in measureable concentrations at this stage of the treatment system. The other trace metal found in significant concentrations in these waters was Ni. A small percentage (&lt;10%) of Ni was removed through co-precipitation and sorption in Cell 1. However, the majority of Ni (≈ 95%) was removed via re- IMWA 2010 Sydney, NS &quot;Mine Water and Innovative Thinking&quot