123,720 research outputs found

    Copernicus observational searches for OH and H2O in diffuse clouds

    Get PDF
    An intensive search for OH and H2O in the directions of sigma Sco, alpha Cam, and micron Per was undertaken with the Copernicus satellite. Multiple scans were carried out over the wavelength region for the expected absorption features due to the OH D-X and H2O C-X transitions. The feature due to OH was detected marginally towards sigma Sco, and only an upper limit can be given towards alpha Cam. H2O was not detected in any of the stars at the signal level accumulated. The OH abundance towards sigma Sco and the respective lower limits for the OH/H2O ratios are discussed with regard to the extant models for the steady state abundances of OH and H2O, and shown not to be inconsistent with ion-molecule schemes

    The posttraumatic stress disorder diagnosis in preschool- and elementary school-age children exposed to motor vehicle accidents

    Get PDF
    Objective: Increasingly, children are being diagnosed with psychiatric disorders, including preschool-age children. These diagnoses in young children raise questions pertaining to 1) how diagnostic algorithms for individual disorders should be modified for young age groups, 2) how psychopathology is best detected at an early stage, and 3) how to make use of multiple informants. The authors examined these issues in a prospective longitudinal assessment of preschool- and elementary school-age children who were exposed to a traumatic event. Method: Participants were 114 children (age range: 2-10 years) who had experienced a motor vehicle accident. Parents and older children (age range: 7-10 years) completed structured interviews 2-4 weeks (initial assessment) and 6 months (6-month follow-up) after the traumatic event. A recently proposed alternative symptom algorithm for diagnosing posttraumatic stress disorder (PTSD) was utilized and compared with the standard DSM-IV algorithms for diagnosing PTSD and acute stress disorder. Results: At the 2- to 4-week assessment, 11.5% of the children met conditions for a diagnosis of PTSD based on the alternative algorithm criteria per parent report, and 13.9% met criteria for this diagnosis at the 6-month follow-up. These percentages were much higher than those for DSM-IV diagnoses of acute stress disorder and PTSD. Among 7- to 10-year-old subjects, the use of combined parent- and child-reported symptoms to derive a diagnosis resulted in an increased number of children in this age group who were identified with psychiatric illness relative to the use of parent report alone. Agreement between parent and child on symptoms for 1) a diagnosis of PTSD based on the alternative algorithm criteria and 2) diagnoses of DSM-IV acute stress disorder and PTSD in this age group was poor. Among 2- to 6-year-old subjects, the alternative algorithm PTSD diagnosis per parent report was a more sensitive predictor of later onset psychopathology relative to a diagnosis of DSM-IV acute stress disorder or PTSD per parent report. However, among 7- to 10-year-old subjects, a combined symptom report (from both parent and child) was optimal in predicting posttraumatic psychopathology. Conclusions: These findings support the use of the proposed alternative algorithm for assessing PTSD in young children and suggest that the diagnosis of PTSD based on the alternative algorithm criteria is stable from the acute phase onward. When both parent- and child-reported symptoms are utilized for the assessment of PTSD among 7- to 10-year-old children, the alternative algorithm and DSM-IV criteria have broad comparable validity. However, in the absence of child-reported symptoms, the alternative algorithm criteria per parent report appears to be an optimal diagnostic measure of PTSD among children in this age group, relative to the standard DSM-IV algorithm for diagnosing the disorder

    NGC1333/IRAS4: A multiple star formation laboratory

    Get PDF
    We present SCUBA observations of the protomultiple system NGC1333/IRAS4 at 450um and 850um. The 850um map shows significant extended emission which is most probably a remnant of the initial cloud core. At 450um, the component 4A is seen to have an elongated shape suggestive of a disk. Also we confirm that in addition to the 4A and 4B system, there exists another component 4C, which appears to lie out of the plane of the system and of the extended emission. Deconvolution of the beam reveals a binary companion to IRAS4B. Simple considerations of binary dynamics suggest that this triple 4A-4BI-4BII system is unstable and will probably not survive in its current form. Thus IRAS4 provides evidence that systems can evolve from higher to lower multiplicity as they move towards the main sequence. We construct a map of spectral index from the two wavelengths, and comment on the implications of this for dust evolution and temperature differences across the map. There is evidence that in the region of component 4A the dust has evolved, probably by coagulating into larger or more complex grains. Furthermore, there is evidence from the spectral index maps that dust from this object is being entrained in its associated outflow.Comment: 10 pages, 10 figures. To appear in MNRAS. Uses mn.sty. Also available at http://www.astro.phys.ethz.ch/papers/smith/smith_p_m.htm

    Research on computer aided testing of pilot response to critical in-flight events

    Get PDF
    Experiments on pilot decision making are described. The development of models of pilot decision making in critical in flight events (CIFE) are emphasized. The following tests are reported on the development of: (1) a frame system representation describing how pilots use their knowledge in a fault diagnosis task; (2) assessment of script norms, distance measures, and Markov models developed from computer aided testing (CAT) data; and (3) performance ranking of subject data. It is demonstrated that interactive computer aided testing either by touch CRT's or personal computers is a useful research and training device for measuring pilot information management in diagnosing system failures in simulated flight situations. Performance is dictated by knowledge of aircraft sybsystems, initial pilot structuring of the failure symptoms and efficient testing of plausible causal hypotheses

    Maladaptive Cognitive Appraisals Mediate the Evolution of Posttraumatic Stress Reactions:A 6-Month Follow-Up of Child and Adolescent Assault and Motor Vehicle Accident Survivors

    Get PDF
    A prospective longitudinal follow-up study (n = 59) of child and adolescent survivors of physical assaults and motor vehicle accidents assessed whether cognitive processes predicted posttraumatic stress symptomatology (PTSS) at 6 months posttrauma in this age group. In particular, the study assessed whether maladaptive posttraumatic appraisals mediated the relationship between initial and later posttraumatic stress. Self-report measures of PTSS, maladaptive appraisals, and other cognitive processes, as well as structured interviews assessing for acute stress disorder and posttraumatic stress disorder (PTSD), were completed at 2-4 weeks and 6 months posttrauma. PTSS and PTSD at 6 months were associated with maladaptive appraisals and other cognitive processes but not demographic or objective trauma severity variables. Only maladaptive appraisals were found to associate with PTSS/PTSD after partialing out initial symptoms/diagnosis and to mediate between initial and later PTSS. It was argued that, on this basis, maladaptive appraisals are involved in the development and maintenance of PTSS over time, whereas other cognitive processes (e.g., subjective threat, memory processes) may have an effect only in the acute phase. The implications of this study for the treatment of PTSS in youths are discussed

    The role of the family in child and adolescent posttraumatic stress following attendance at an emergency department

    Get PDF
    Objective: To evaluate the role of family factors in posttraumatic stress symptomatology (PTSS) in children and adolescents who have attended an emergency department following assaults or motor vehicle accident. Methods: Children and their parents completed self-report questionnaires and semistructured interviews relating to their psychopathology and cognitive styles at 2-4 weeks and 6 months after trauma. Results: Parental depression was correlated with child PTSS at each assessment point. Less consistent findings were observed for family functioning. Parental endorsement of worry was a correlate of child PTSS at each assessment and a mediator between parental depression and child PTSS. Conclusions: A role for family factors, in particular parental depression and parental endorsement of worry, in the development of child PTSS is supported. Weaknesses of the study are discussed, and suggestions for future research are given

    Discrepancies in Determinations of the Ginzburg-Landau Parameter

    Full text link
    Long-standing discrepancies within determinations of the Ginzburg-Landau parameter κ\kappa from supercritical field measurements on superconducting microspheres are reexamined. The discrepancy in tin is shown to result from differing methods of analyses, whereas the discrepancy in indium is a consequence of significantly differing experimental results. The reanalyses however confirms the lower κ\kappa determinations to within experimental uncertainties.Comment: submitted to Phys. Rev.

    Feeder Pig Production Opportunities in Southeastern Ohio

    Get PDF

    Separately contacted electron-hole double layer in a GaAs/AlxGa1−xAs heterostructure

    Get PDF
    We describe a method for creating closely spaced parallel two-dimensional electron and hole gases confined in 200 Å GaAs wells separated by a 200 Å wide AlxGa1−xAs barrier. Low-temperature ohmic contacts are made to both the electrons and holes, whose densities are individually adjustable between 10^(10)/cm^2 to greater than 10^(11)/cm^2
    • …
    corecore