2,697 research outputs found

    Bayesian analysis of the multivariate dependence of three transition water ecosystem classifications

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    The Water Framework Directive (WFD) recognizes benthic macroinvertebrates as a good biological quality element for transitional waters as they are the most exposed to natural variability patterns characteristic of these ecosystems, due to their life cycles and space-use behavior. Here, we address the ecological status classification issue for three lagoons in Apulia, using benthic macroinvertebrates and three proposed multimetric indices (namely M-AMBI, BITS and ISS), likely to respond differently to different sources of stress and natural variability. Lagoon classification is based on discretization by standard classification boundaries with only partial consideration of the natural variability of ecosystem properties and possible inaccuracies of the classification procedures. In order to investigate the possible contrasting behavior of the three classifications, we propose Bayesian hierarchical models in which the multimetric indices and their discrete counterparts are jointly modeled as function of abiotic covariates, external anthropogenic pressures indicators and spatio-temporal effects

    Developing Commitment Towards Change in Bureaucracies: The Case-Study of the Egyptian Civil Service Sector

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    This thesis examines the management of change in bureaucracies, with a study focus on the Egyptian civil service sector. The main research aims are to identify what are the main problems of the Egyptian civil service sector, identify the main barriers against the current change programmes undertaken by the Government of Egypt (GOE) and suggest ways to develop civil servants’ commitment towards those changes. Interview data was triangulated with archival documents and non-participant observation and were drawn from a sample of 33 civil servants working in the Egyptian Ministry of State for Administrative Development (MSAD) which is the civil service entity acting as the change agent responsible for managing the government administrative reforms plan in the civil service sector. All study participants were actually working in one of the change projects/programmes and had a minimum of 12 months of service in the civil service. Interviews were digitally-recorded and transcribed in the form of MS-Word documents, and data transcripts were analysed manually using MS-Excel worksheets and main research themes were developed and statistics drawn using those Excel worksheets. The main research findings suggested that the main problems of the Egyptian civil service sector are (1) the absence of a Reward and Punishment system, (2) the absence of a firm system of governance and control and (3) the current negative civil service culture. The research findings suggested that developing civil servants’ commitment towards change may be achieved by employee involvement and participation in the change process and the careful selection of inspirational change agents. The findings also suggested that change agents play an important role in inspiring civil servants to support change and that middle management is another crucial factor in the change move as it should act as liaison between change agents and employees

    Service user leadership: training and development for service users to take the lead

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    Purpose – This paper outlines the concept of service user leadership and both describes and reflects on an accredited training programme that enables mental health service users to take a leadership role. Design/methodology/approach – The authors argue for a service user leadership approach and the training programme is reviewed by previous participants Findings – Service users can take on a leadership role if they are given suitable and relevant training and development opportunities. Service user led training can be transformational. Practical implications – Commissioners of mental health services should consider how to support service user leadership programmes, which can reach places and achieve outcomes that traditional mental health services are unable to attain. Originality/value – The concept of service user leadership is relatively new and the training programme described in this paper is both original and highly valued by participants with many significant outcomes. Keywords Service user leadership, Peer support, Empowerment, Service user involvement, Confidence, Wellbeing, Leadership, Trainin

    Spatial and seasonal variability of fractionated phytoplankton biomass and primary production in the frontal region of the Northern Adriatic Sea

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    Spatial and seasonal patterns of variation of fractionated phytoplankton biomass and primary production and their relationships with nutrient concentrations were analyzed along an inshore - offshore gradient and in relation to the presence of a frontal system in the Northern Adriatic Sea. Sampling was carried out in winter and summer during four oceanographic cruises (June 1996 and 1997, February 1997 and 1998) as part of the PRISMA II project. Water samples for determining nutrient concentrations, phytoplankton biomass (as Chla) and primary production (as 14 C assimilation) were collected at five optical depths. Sampling stations were located along 2 or 4 parallel transects arranged perpendicularly to the shoreline and the frontal system. The transects were located at such a distance from the coast that the frontal system crossed them at their halfway point. Total dissolved nitrogen (TDN) and total dissolved phosphorus concentrations (TDP) were 12.41 ± 3 .95 mM and 0.146 ± 0 .070 mM, respectively. The values in the two seasonal periods were similar, decreasing along the inshore-offshore gradient. Values for phytoplankton biomass and primary productionwere higher in the winter than the summer cruises, and decreased, in both seasonal periods, along the inshore / offshore gradient. Moreover, in both seasonal periods, picophytoplankton dominated both biomass and productivity, (56% and 44%, respectively) at stations beyond the frontal system, while microphytoplankton was more important at stations inside it (44% and 44%, respectively). Total phytoplankton biomass and primary production were directly related to nutrient concentrations. Regarding size classes, significant patterns of variation with nutrients were observed particularly for biomass. The results indicate that the size structure and function of phytoplankton guilds seem to be mediated by nutrient inflow, as well as by competitive interaction among size fractions

    Biovolume determination of phytoplankton guilds in transitional water ecosystems of Mediterranean Ecoregion

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    1 - Conceptually, morphometric measurements of phytoplankton guilds seem to have major advantages as descriptors of the ecological status of transitional water ecosystems (TW) with respect to classical taxonomic descriptors. However, at present, standardized or common methodologies for the use of morphometric descriptors do not exist. 2 - This paper aims to provide a starting point for the activation of standardized methods for the determination of morphometric descriptors of phytoplankton as a quality element in TW in accordance with the new directive of WFD 2000/60/EU. 3 - Phytoplankton biovolume is one of the most studied morphometric descriptors. It can be estimated by associating the algae with similar geometric forms and determining the volume of these by measuring the linear dimensions required for its calculation under the microscope. However, the lack of a standardized set of geometric forms and equations for calculating biovolume causes difficulties and produces data that are not comparable. 4 - A set of geometric models is suggested here for calculating the cell biovolumes of 201 phytoplankton genera found in transitional water ecosystems of Mediterranean Ecoregion. The equations were designed to minimize the effort of microscopic measurements. The main methodological problems, and the similarities and differences between our own and previously published proposals are discussed

    Quantum Noise Measurement of a Carbon Nanotube Quantum Dot in the Kondo Regime

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    The current emission noise of a carbon nanotube quantum dot in the Kondo regime is measured at frequencies ν\nu of the order or higher than the frequency associated with the Kondo effect kBTK/hk_B T_K/h, with TKT_K the Kondo temperature. The carbon nanotube is coupled via an on-chip resonant circuit to a quantum noise detector, a superconductor-insulator-superconductor junction. We find for hν≈kBTKh \nu \approx k_B T_K a Kondo effect related singularity at a voltage bias eV≈hνeV \approx h \nu , and a strong reduction of this singularity for hν≈3kBTKh \nu \approx 3 k_B T_K, in good agreement with theory. Our experiment constitutes a new original tool for the investigation of the non-equilibrium dynamics of many-body phenomena in nanoscale devices.Comment: 6 pages, 4 figure

    Spin orbit coupling at the level of a single electron

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    We utilize electron counting techniques to distinguish a spin conserving fast tunneling process and a slower process involving spin flips in AlGaAs/GaAs-based double quantum dots. By studying the dependence of the rates on the interdot tunnel coupling of the two dots, we find that as many as 4% of the tunneling events occur with a spin flip related to spin-orbit coupling in GaAs. Our measurement has a fidelity of 99 % in terms of resolving whether a tunneling event occurred with a spin flip or not

    High Frequency Quantum Admittance and Noise Measurement with an On-chip Resonant Circuit

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    By coupling a quantum detector, a superconductor-insulator-superconductor junction, to a Josephson junction \textit{via} a resonant circuit we probe the high frequency properties, namely the ac complex admittance and the current fluctuations of the Josephson junction at the resonant frequencies. The admittance components show frequency dependent singularities related to the superconducting density of state while the noise exhibits a strong frequency dependence, consistent with theoretical predictions. The circuit also allows to probe separately the emission and absorption noise in the quantum regime of the superconducting resonant circuit at equilibrium. At low temperature the resonant circuit exhibits only absorption noise related to zero point fluctuations, whereas at higher temperature emission noise is also present.Comment: 15 pages, 15 figure

    Immunology: Investigations on the cell type responsible for the endometrial secretion of complement component 3 (C3)

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    It has been shown that and human endometria have the capacity to produce complement component 3 (C3). In rats, endometrial C3 is an oestrogen-dependent protein produced and secreted by glandular cells. The cell responsible for the synthesis and secretion of human endometrial C3 has not been clearly defined. Our study was aimed at answering this question. Samples of endometrium obtained from hysterectomies were either immunostained for C3 or digested with collagenase; then the stromal and glandular cells were separated and immunopurified (or not) with an antibody to CD45 coupled to magnetic beads to eliminate the endometrial lymphomyeloid cells. Cells were cultured for 2 weeks and C3 measured in the medium by an in-house radioimmunoassay. Glandular as well as stromal cells stained positively for C3 and released C3 in vitro. The release of C3 from both cell types could be inhibited by cycloheximide. Epithelial cells produced significantly more C3 than stromal cells, and endometrial C3 production was higher for both cell types when these were obtained from secretory as compared to proliferative endometria. Lymphomyeloid cells were possibly a source of C3 since after immunoadsorption of these cells, the remaining stromal or glandular cells produced significantly less C3. We conclude that endometrial stromal, glandular and lymphomyeloid cells all produce C
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