X-ray observations of the Ultraluminous infrared galaxy IRAS19254-7245 (The Superantennae)

We present ROSAT HRI and ASCA observations of the well known ULIRG IRAS19254-7245 (the Superantennae). The object is not detected by ROSAT yielding a 3\sigma upper limit of L_x ~8x10^{41} erg/s in the 0.1-2 keV band. However, we obtain a clear detection by ASCA yielding a luminosity in the 2-10 keV band of 2 \times 10^{42}erg/s. Its X-ray spectrum is very hard, equivalent to a photon index of Gamma=1.0+-0.35. We therefore, attempt to model the X-ray data with a "scatterer" model in which the intrinsic X-ray emission along our line of sight is obscured by an absorbing screen while some fraction, f, is scattered into our line of sight by an ionized medium; this is the standard model for the X-ray emission in obscured (but non Compton-thick) Seyfert galaxies. We obtain an absorbing column of 2x10^{23}cm^{-2} for a power-law photon index of Gamma=1.9, an order of magnitude above the column estimated on the basis of optical observations; the percentage of the scattered emission is high (~20%). Alternatively, a model where most of the X-ray emission comes from reflection on a Compton thick torus (N_H>10^{24} cm^{-2}) cannot be ruled out. We do not detect an Fe line at 6.4 keV; however, the upper limit (90%) to the equivalent width of the 6.4 keV line is high (~3 keV). All the above suggest that most of the X-ray emission originates in an highly obscured Seyfert-2 nucleus.Comment: 5 pages, 1 figure, 1 table, To appear in MNRA

Nitrogen transfer between clover and wheat in an intercropping experiment

A novel approach to the problem of improving nitrogen supply in organic farming is to use intercropping of cereals with a legume to provide nitrogen transfer within a season and/or to following crops. The affects of intercropping were studied in a column experiment using mixtures of winter wheat (Triticum aestivum cv. Claire), with white clover (w.c.) (Trifolium repens cv. Barblanca) and with red clover (r.c.) (Trifolium pratense cv. Britta). The effects of cutting and removal above ground clover material with and without additional soil disturbance were compared to leaving clover plants in situ and intercropped with wheat in a split root design. Wheat and clover plants, as monocultures, were used for the controls. 15N ammonium nitrate solution was applied. The wheat seeds were sown into the column without nitrogen. We found that the cutting treatment produced the highest yield of wheat. Available ammonium-N in the soil was greatest in the clover control treatment for the column with only red clover roots and in the cutting+soil disturbance treatment for the column with only white clover roots. Available nitrate-N was greatest in the soil disturbance treatment in the column with clover and wheat roots for both red and white clover. The cutting treatment produced the highest yield of wheat

A study of air-to-ground sound propagation using an instrumented meteorological tower

The results of an exploratory NASA study, leading to a better understanding of the effects of meteorological conditions on the propagation of aircraft noise, are reported. The experimental program utilized a known sound source fixed atop an instrumented meteorological tower. The basic experimental scheme consisted of measuring the amplitude of sound radiated toward the ground along a line of microphones fixed to a tower guy wire. Experimental results show the feasibility of this approach in the acquisition of data indicating the variations encountered in the time-averaged and instantaneous amplitudes of propagated sound. The investigation included a consideration of ground reflections, a comparison of measured attenuations with predicted atmospheric absorption losses, and an evaluation of the amplitude fluctuations of recorded sound pressures

Cosmological Evolution in a Type-0 String Theory

We study the cosmological evolution of a type-0 string theory by employing non-criticality, which may be induced by fluctuations of the D3 brane worlds. We check the consistency of the approach to O(alpha ') in the corresponding sigma-model. The ten-dimensional theory is reduced to an effective four-dimensional model, with only time dependent fields. We show that the four-dimensional universe has an inflationary phase and graceful exit from it, while the other extra dimensions are stabilized to a constant value, with the fifth dimension much larger than the others. We pay particular attention to demonstrating the role of tachyonic matter in inducing these features. The Universe asymptotes, for large times, to a non-accelerating linearly-expanding Universe with a time-dependent dilaton and a relaxing to zero vacuum energy a la quintessence.Comment: 33 pages LATEX, seven eps figures incorporate

Profiles and trajectories of mental health service utilisation during early intervention in psychosis

Background: Early intervention in psychosis services (EIS) support individuals experiencing a first episode of psychosis. Support required will vary in response to the remittance and reoccurrence of symptoms, including relapses. Characterising individuals who will need more intensive support can inform care planning. This study explores service utilisation profiles and their trajectories of service use in a sample of individuals referred to EIS. Method: We analysed service utilisation during the 3 years following referral to EIS (n = 2363) in West London between 2011 and 2020. Mental health service utilisation data were submitted to model-based clustering. Latent growth models were then estimated for identified profiles. Profiles were compared regarding clinical and demographic characteristics and onward pathways of care. Results: Analyses revealed 5 profiles of individuals attending EIS based on their service utilisation over 3 years. 55.5% of the sample were members of a low utilisation and less clinically severe profile. The distinct service use patterns of these profiles were associated with Health of the Nations Outcome Scale scores at treatment initiation (at total, subscale, and individual item level), along with age and gender. These patterns of use were also associated with onward care and ethnicity. Conclusions: Profiles and trajectories of service utilisation call for development of integrated care pathways and use of more personalised interventions. Services should consider patient symptoms and characteristics when making clinical decisions informing the provision of care. The profiles represent typical patterns of service use, and identifying factors associated with these subgroups might help optimise EIS support

The X-ray spectra of optically selected Seyfert 2 galaxies. Are there any Sy2 galaxies with no absorption?

We present an X-ray spectral analysis of a sample of 8 bona-fide Seyfert 2 galaxies, selected on the basis of their high $[OIII]\lambda5007$ flux, from the Ho et al. (1997) spectroscopic sample of nearby galaxies. We find that, in general, the X-ray spectra of our Seyfert 2 galaxies are complex, with some our objects having spectra different from the 'typical' spectrum of X-ray selected Seyfert 2 galaxies. Two (NGC3147 and NGC4698) show no evidence for intrinsic absorption. We suggest this is due to the fact that when the torus suppresses the intrinsic medium and hard energy flux, underlying emission from the host galaxy, originating in circumnuclear starbursts, and scattering from warm absorbers contributes in these energy bands more significantly. Our asca data alone cannot discriminate whether low absorption objects are Compton-thick AGN with a strong scattered component or lack an obscuring torus. The most striking example of our low absorption Seyfert 2 is NGC4698. Its spectrum could be explained by either a dusty warm absorber or a lack of broad line clouds so that its appearance as a Seyfert 2 is intrinsic and not due to absorption.Comment: 12 pages, to be published in MNRA

Library and information resources and users of digital resources in the humanities

Purpose – The purpose of this article is to discuss the results of the Log Analysis of Internet Resources in the Arts and Humanities (LAIRAH) study. It aims to concentrate upon the use and importance of information resources, physical research centres and digital finding aids in scholarly research. Design/methodology/approach – Results are presented of web server log analysis of portals for humanities scholars: the arts and humanities data service (AHDS) website and Humbul Humanities Hub. These are used to determine which resources were accessed most often, or seldom. Questionnaire data about perceptions of digital resource use were also gathered. Findings – Information resources such as libraries, archives museums and research centres, and the web pages that provide information about them are vital for humanities scholars. The university library website was considered to be the most important resource, even compared to Google. Secondary finding aids and reference resources are considered more important than primary research resources, especially those produced by other scholars, whose output is less trusted than publications produced by commercial organisations, libraries, archives and museums. Practical implications – Digital resources have not replaced physical information resources and the people who staff them, thus both types of information continue to require funding. Scholars trust the judgment of information professionals, who therefore need to be trained to evaluate and recommend specialist digital research resources. Originality/value – LAIRAH was the first research project to use quantitative data to investigate resource use. Findings about the type of resources used are based on evidence rather than opinions alone. This gives a clearer picture of usage that may be used to plan future information services

Autonomous Modal Identification of the Space Shuttle Tail Rudder

Autonomous modal identification automates the calculation of natural vibration frequencies, damping, and mode shapes of a structure from experimental data. This technology complements damage detection techniques that use continuous or periodic monitoring of vibration characteristics. The approach shown in the paper incorporates the Eigensystem Realization Algorithm (ERA) as a data analysis engine and an autonomous supervisor to condense multiple estimates of modal parameters using ERA's Consistent-Mode Indicator and correlation of mode shapes. The procedure was applied to free-decay responses of a Space Shuttle tail rudder and successfully identified the seven modes of the structure below 250 Hz. The final modal parameters are a condensed set of results for 87 individual ERA cases requiring approximately five minutes of CPU time on a DEC Alpha computer

Young adults' perceptions of using wearables, social media and other technologies to detect worsening mental health: A qualitative study

BACKGROUND: Technological interventions may help support and improve mental health. However young peoples' perspectives on using different technologies to detect deteriorating mental health in those already diagnosed with a mental health condition is lacking. The study aim was to explore the perspectives of young patients on the feasibility and acceptability of using wearables, social media and technologies to detect mental health deterioration. METHODS: The study was co-produced with young adults with past mental health difficulties. Semi-structured interviews were conducted with young adults with a severe mental health condition in a private room at a community mental health site. Data was triangulated by comparing codes and ideas across the two co-researchers and two researchers over two virtual meetings. Themes were finalised and presented in a thematic map. RESULTS: Sixteen participants were interviewed (81% female). There were four main themes: dealing with mental health symptoms, signs of mental health deterioration, technology concerns and technological applications to identify worsening mental health. Wearables and mobile apps were considered acceptable and feasible to detect mental health deterioration in real-time if they could measure changes in sleep patterns, mood or activity levels as signs of deterioration. Getting help earlier was deemed essential particularly in reference to dissatisfaction with the current non-technological mental health services. However, patients identified issues to consider before implementation including practicality, safeguarding and patient preference. CONCLUSION: Wearables and mobile apps could be viable technological options to help detect deterioration in young people in order to intervene early and avoid delay in accessing mental health services. However, immediate action following detection is required for the patient to trust and use the intervention

Small molecule additive for low-power accumulation mode organic electrochemical transistors

A small molecule additive, dodecylbenzenesulfonate (DBSA), is added to the electrolyte in OECTs to improve the device performance.ERC IMBIBE EPSRC CDT Plastic Electronic