781 research outputs found
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
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 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
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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
The organization of frequency and binaural cues in the gerbil inferior colliculus: GRAÑA et al.
The inferior colliculus (IC) is the common target of separate pathways that transmit different types of auditory information. Beyond tonotopy, little is known about the organization of response properties within the 3-dimensional layout of the auditory midbrain in most species. Through study of interaural time difference (ITD) processing, the functional properties of neurons can be readily characterized and related to specific pathways. To characterize the representation of ITDs relative to the frequency and hodological organization of the IC, the properties of neurons were recorded and the sites recovered histologically. Subdivisions of the IC were identified based on cytochrome oxidase (CO) histochemistry. The results were plotted within a framework formed by an MRI atlas of the gerbil brain. The central nucleus was composed of two parts, and lateral and dorsal cortical areas were identified. The lateral part of the central nucleus had the highest CO activity in the IC and a high proportion of neurons sensitive to ITDs. The medial portion had lower CO activity and fewer ITD-sensitive neurons. A common tonotopy with a dorsolateral to ventromedial gradient of low to high frequencies spanned the two regions. The distribution of physiological responses was in close agreement with known patterns of ascending inputs. An understanding of the 3-dimensional organization of the IC is needed to specify how the single tonotopic representation in the IC central nucleus leads to the multiple tonotopic representations in core areas of the auditory cortex
Elicitation formats and the WTA/WTP gap: A study of climate neutral foods
We conduct a field valuation experiment where we vary the valuation method (contingent valuation vs. inferred valuation) as well as the payment format (dichotomous choice vs. payment card). Willingness-to-accept and willingness-to-pay valuations are elicited in a within-subjects design for foods with climate neutral labels. We find a similar gap for valuations elicited with the contingent or the inferred valuation method. However, we also find that the gap can be muted by using a payment card elicitation format
Elicitation formats and the WTA/WTP gap: A study of climate neutral foods
We conduct a field valuation experiment where we vary the valuation method (contingent valuation vs. inferred valuation) as well as the payment format (dichotomous choice vs. payment card). Willingness-to-accept and willingness-to-pay valuations are elicited in a within-subjects design for foods with climate neutral labels. We find a similar gap for valuations elicited with the contingent or the inferred valuation method. However, we also find that the gap can be muted by using a payment card elicitation format
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