2,167 research outputs found
DBT degradation enhancement by decorating Rhodococcus erythropolis IGST8 with magnetic Fe3O4 nanoparticles
Biodesulfurization (BDS) of dibenzothiophene (DBT) was carried out by Rhodococcus erythropolis IGST8 decorated with magnetic Fe3O4 nanoparticles, synthesized in-house by a chemical method, with an average size of 45-50 nm, in order to facilitate the post-reaction separation of the bacteria from the reaction mixture. Scanning electron microscopy (SEM) showed that the magnetic nanoparticles substantially coated the surfaces of the bacteria. It was found that the decorated cells had a 56% higher DBT desulfurization activity in basic salt medium (BSM) compared to the nondecorated cells. We propose that this is due to permeabilization of the bacterial membrane, facilitating the entry and exit of reactant and product, respectively. Model experiments with black lipid membranes (BLM) demonstrated that the nanoparticles indeed enhance membrane permeability
Electron localisation in static and time-dependent one-dimensional model systems
Electron localization is the tendency of an electron in a many-body system to
exclude other electrons from its vicinity. Using a new natural measure of
localization based on the exact manyelectron wavefunction, we find that
localization can vary considerably between different ground-state systems, and
can also be strongly disrupted, as a function of time, when a system is driven
by an applied electric field. We use our new measure to assess the well-known
electron localization function (ELF), both in its approximate single-particle
form (often applied within density-functional theory) and its full
many-particle form. The full ELF always gives an excellent description of
localization, but the approximate ELF fails in time-dependent situations, even
when the exact Kohn-Sham orbitals are employed.Comment: 7 pages, 4 figure
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Associated reading skills in children with a history of Specific Language Impairment (SLI)
A large cohort of 200 eleven-year-old children with Specific Language Impairment (SLI) were assessed on basic reading accuracy and on reading comprehension as well as language tasks. Reading skills were examined descriptively and in relation to early language and literacy factors. Using stepwise regression analyses in which age and nonverbal IQ were controlled for, it was found that a single word reading measure taken at 7 years was unsurprisingly a strong predictor of the two different types of reading ability. However, even with this measure included, a receptive syntax task (TROG) entered when reading accuracy score was the DV. Furthermore, a test of expressive syntax/narrative and a receptive syntax task completed at 7 years entered into the model for word reading accuracy. When early reading accuracy was excluded from the analyses, early phonological skills also entered as a predictor of both reading accuracy and comprehension at 11 years. The group of children with a history of SLI were then divided into those with no literacy difficulties at 11 and those with some persisting literacy impairment. Using stepwise logistic regression, and again controlling for IQ and age, 7 years receptive syntax score (but not tests of phonology, expressive vocabulary or expressive syntax/narrative) entered as a positive predictor of membership of the āno literacy problemsā group regardless of whether early reading accuracy was controlled for in step one. The findings are discussed in relation to the overlap of SLI and dyslexia and the long term sequelae of language impairment
Managing the humanitarian supply chain: developing a generic model to improve collaboration, efficiency and effectiveness
Humanitarian disasters are expected to increase 5-fold over the next 50 years. It is suggested that the scale of resource dedicated to logistics provision in response to disasters accounts for upwards of 80% of the total budget, hence humanitarian logistics is very much in the spotlight. Collaborative working has been promoted as a Silver Bullet in many areas of Supply Chain Management and is contended to be a mechanism to prevent organisations optimising solely their own results, rather than integrating their goals and activities with others to benefit overall end user value. Collaborative techniques inherent within commercial supply chains have not been observed in the humanitarian relief chain. This study investigates why this is the case, as this lack of collaboration leads to inefficiency; which at worst results in increased humanitarian suffering and additional loss of life. The findings reveal ways to advance collaborative working within the humanitarian relief supply chain. A conceptual generic model of the supply chain is developed which highlights significant issues which, if addressed will improve collaboration and thereby benefit overall
efficiency and effectiveness
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Do emotional difficulties and peer problems hew together from childhood to adolescence? The case of children with a history of developmental language disorder (DLD)
Children and adolescents with developmental language disorder (DLD) are, overall, vulnerable to difficulties in emotional adjustment and in peer relations. However, previous research has shown that different subgroups follow different trajectories in respect of quality of peer relations. Less is known of the trajectories of emotional development. We consider here the possibility that development in these two domains is interrelated: that is, the trajectories of emotional and peer problems will proceed in parallel. We conducted longitudinal joint trajectories analyses of emotional and peer relations in a sample of young people identified as having DLD at age 7 years and seen at intervals up to 16 years. Potential influences on joint trajectory group membership were examined. Findings revealed five distinct joint trajectories. Emotional and peer difficulties do hew together from childhood to adolescence for just over half of the sample, but not all. The variables most clearly associated with group membership were pragmatic language ability, prosociality and parental mental health. This is the first study to examine joint longitudinal trajectories of emotional and peer difficulties in individuals with DLD. We demonstrate that development in individuals with DLD is heterogeneous and identify three key variables associated with personal and social adjustment from childhood to adolescence. Theoretical and clinical implications of these findings are discussed
Cochlear reimplantation
Since its inception in 1988 the Cochlear Implant Programme in Manchester has successfully implanted 69 adults and 23 children. Of these 92 procedures, three patients have undergone revision surgery with the insertion of either a new implant or re-positioning of the existing device. We examine the circumstances that lead to the need for reimplantation in these patients, discuss the technical aspects of revision surgery together with the functional results of such procedures. Re-operatio
Managing the humanitarian supply chain: a collaborative approach?
Humanitarian disasters are expected to increase 5-fold over the next 50 years. In 2010 a total of 385 separate disasters killed over 297,000 people worldwide, affected more than 217 million others and caused US$ 123.9 billion of economic damages. It is suggested that the scale of resource dedicated to logistics provision in response to disasters accounts for upwards of 80% of the total budget, hence humanitarian logistics both as a practice and a research topic is very much in the spotlight. Consequently, this research addresses what is argued to be the under-representation of humanitarian logistics in the literature and the associated lack of empirical research focussed on the management of the supply chain.
Collaborative working has been promoted as a Silver Bullet in many areas of Supply Chain Management and is contended to be a mechanism to prevent organisations optimising solely their own results rather than integrating their goals and activities with others to benefit overall end user value. Collaborative techniques inherent within commercial supply chains have not been observed in the humanitarian relief chain. This study investigates why this is the case, as this lack of collaboration is reported to lead to inefficiency; which at worst results in increased humanitarian suffering and additional loss of life. Hence, the findings reveal ways to advance collaborative working within the humanitarian relief supply chain.
Criticism is levelled at the predominance of quantitative methodologies in current research within humanitarian logistics. This study addresses this gap as well as the calls for more cross-organisational case studies within the field, by adopting a multi-case, qualitative approach based on the triangulation of data gathered during a series of in-depth interviews and focus groups across 4 separate humanitarian relief organisations. Data interpretation is through content analysis to identify specific patterns and themes. The research concerns itself with the response immediately following the onset of a disaster. This limited scope helps to address issues surrounding the generalisability of a purely qualitative approach whilst also maintaining control over data volume; however, there are still ample opportunities for significant theoretical and practical contribution.
The findings identify specific barriers to collaborative working within the sector; in particular, themes and patterns within management and control, understanding and training, relationships, and military involvement have surfaced. Outcomes also have implications for commercial supply chain managers who are increasingly faced with challenges that no longer obey the traditional rules of forecast driven certainty and predictability, and are therefore, expected to adopt the more event driven, agile and flexible approaches that are already a reality for their humanitarian sector counterparts.
The study concludes with the development of a conceptual generic model of the humanitarian supply chain that includes a number of significant issues which, if addressed will improve collaboration and thereby benefit overall efficiency and effectiveness to the general betterment of future relief provision
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