235 research outputs found
Metering and adaptive protection for a microgrid with distributed generation
The main objective of this project is to develop an adaptive relaying system that will protect the microgrid both in connected and isolated modes. Therefore the settings for the different relays will be observed for the two modes of operation. This will determine whether they are correctly coordinated in order to operate as an adaptive relaying system. A secondary but also important objective is to identify load management techniques through smart metering that could facilitate power system operation and in turn power system protection. To achieve the goal of this project the proposed relaying system will have to prove appropriate in all the test cases. Based on the results obtained in the simulations, conclusions about the relaying scheme were drawn. Based on cases where the scheme seemed inappropriate or could be improved, recommendations were made. The relaying scheme proposed in this project proved highly successful in detecting abnormalities and protecting the power system when necessary
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Development and Initial Validation of the Multicultural Gender Roles Scale—Black Women (MGRS – BW)
The purpose of this study was to develop and evaluate a scale that measures more accurate and flexible gender role representations of Black women regarding themselves and others. Scholars have called for the development of gender role instruments that measure more culturally relevant interpretations of masculinity and femininity (Dade & Sloan, 2000; Miville, 2013). Instruments that incorporate traditional Euro-centric notions of gender roles do not account well for the unique racial-ethnic contexts that likely influence how Black women construct gender as well as perpetuate the misrepresentation of black femininity, the justification of negative stereotypes of Black women (e.g., the Mammy, Jezebel and Sapphire), and the exclusion of Black women from healthy expressions of womanhood (Dade & Sloan, 2000; Harris, 1994). This study referred to the Multicultural Gender Roles Model (MGRM; Miville, Bratini, Corpus, Lau, and Redway, 2013) in an effort to better describe the gendered experiences Black women. The Multicultural Gender Roles Scale - Black Women (MGRS-BW) reflected a 22 Likert-type item scale reflecting a 3-factor structure. Reliability and construct validity was established in several ways: expert ratings, alpha coefficients, and exploratory and confirmatory factor analyses. Implications for future research and clinical applications also were presented
The International Finance Facility for Immunisation: stakeholders' perspectives.
OBJECTIVE: To evaluate stakeholders' understanding and opinions of the International Finance Facility for Immunisation (IFFIm); to identify factors affecting funding levels; and to explore the future use of IFFIm. METHODS: Between July and September 2015, we interviewed 33 individuals from 25 organizations identified as stakeholders in IFFIm. In total 22.5 hours of semi-structured interviews were recorded, transcribed and analysed using a framework method. FINDINGS: Stakeholders' understanding of IFFIm's financing mechanism and its outcomes varied and many stakeholders wanted more information. Participants highlighted that the change in the macro-economic environment following the 2008 financial crisis affected national policy in donor countries and subsequently the number of new commitments IFFIm received. Since Gavi is now seen as a successful and mature organization, participants stated that donors prefer to donate directly to Gavi. The pharmaceutical industry valued IFFIm for providing funding stability and flexibility. Other stakeholders valued IFFIm's ability to access funds early and enable Gavi to increase vaccine coverage. Overall, stakeholders thought IFFIm was successful, but they had divergent views about IFFIm's on-going role. Participants listed two issues where bond financing mechanisms may be suitable: emergency preparedness and outcome-based time-limited interventions. CONCLUSION: The benefit of pledging funds through IFFIm needs to be re-evaluated. There are potential uses for bond financing to raise funds for other global health issues, but these must be carefully considered against criteria to establish effectiveness, with quantifiable pre-defined outcome indicators to evaluate performance
A process evaluation of how the routine vaccination programme is implemented at GP practices in England.
BACKGROUND: In recent years, the incidence of several pathogens of public health importance (measles, mumps, pertussis and rubella) has increased in Europe, leading to outbreaks. This has included England, where GP practices implement the vaccination programme based on government guidance. However, there has been no study of how implementation takes place, which makes it difficult to identify organisational variation and thus limits the ability to recommend interventions to improve coverage. The aim of this study is to undertake a comparative process evaluation of the implementation of the routine vaccination programme at GP practices in England. METHODS: We recruited a sample of geographically and demographically diverse GP practices through a national research network and collected quantitative and qualitative data as part of a Time-Driven Activity-Based Costing analysis between May 2017 and February 2018. We conducted semi-structured interviews with practice staff involved in vaccination, who then completed an activity log for 2 weeks. Interviews were transcribed and coded using a framework method. RESULTS: Nine practices completed data collection from diverse geographic and socio-economic contexts, and 52 clinical and non-clinical staff participated in 26 interviews. Information relating to 372 vaccination appointments (233 childhood and 139 adult appointments) was captured using activity logs. We have defined a 14-stage care delivery value chain and detailed process map for vaccination. Areas of greatest variation include the method of reminder and recall activities, structure of vaccination appointments and task allocation between staff groups. For childhood vaccination, mean appointment length was 15.9 min (range 9.0-22.0 min) and 10.9 min for adults (range 6.8-14.1 min). Non-clinical administrative activities comprised 59.7% total activity (range 48.4-67.0%). Appointment length and total time were not related to coverage, whereas capacity in terms of appointments per eligible patient may improve coverage. Administrative tasks had lower fidelity of implementation. CONCLUSIONS: There is variation in how GP practices in England implement the delivery of the routine vaccination programme. Further work is required to evaluate capacity factors in a wider range of practices, alongside other contextual factors, including the working culture within practices
Relations Bassin versant Cours d'eau. Le cas des fleuves des Pyrénées Orientales.
L'ensemble des cours d'eau des régions méridionales françaises a subi depuis le 19ème siècle des évolutions majeures et contradictoires. Les bassins versants des principaux fleuves des Pyrénées orientales témoignent de ces transformations, dont les réper
Enhancing innovation through venture capital : lessons from Asia for Nigeria
Innovation is viewed as the main determinant of nations' economic growth and competitiveness in the modern economy. And the important role played by venture capital in financing innovation has been widely documented. This paper attempts to discuss how Nigeria can leverage venture capital to drive innovation by building an efficient venture capital industry drawing lessons from the experience of China, Hong Kong, and South Korea respectively. Findings from our study revealed government intervention through policy initiation, support funds and programs; strong innovation and entrepreneurial ecosystem; favourable tax policies, vibrant stock markets; and active venture capital associations as key success factors. We concluded that for Nigeria to build a flourishing venture capital industry, specific focus should be placed on improving the standard of education, enhancement of the innovation eco-system, improving the environment for venture capitalist exit, strengthening the regulatory framework through sound fiscal policy (taxation), and the intensification of government support for innovative high risk venture projects (small innovative business)
Role of membrane-associated guanylate kinases in somatosensory cortical development
In order to process information, neurons must connect together to form a neuronal
circuit. The formation of neuronal circuits is dependent on synaptic activity through
glutamate receptors and downstream molecules within the post-synaptic density (PSD).
The pathways downstream of glutamate receptors play an important role in maintaining
appropriate synapses and forming neural circuits; mutations in genes that encode PSD
proteins disrupt these pathways and are associated with many forms of intellectual
disability in humans (Grant 2012). The development of neuronal circuits relies on two key
developmental events; neurons must first send out axons locally and to disparate brain
regions and then, neurons must form connections with the dendrites of target neurons.
The rodent trigeminal system is a neuronal circuit that processes somatosensory
information from whiskers on the facepad via nuclei in the brainstem to the thalamus and
ultimately the cerebral cortex. Brain regions that comprise the trigeminal system are
organised in a manner that topographically recapitulates the whisker pattern; each whisker
on the rodent facepad corresponds to a physiological and anatomical unit in the primary
somatosensensory cortex (S1) called a barrel. This topographical organisation creates a
pattern consisting of thalamocortical axons (TCA) clustered into distinct whisker-related
bundles and layer IV spiny stellate cells which segregate around the outside of TCA bundles.
Three different anatomical patterns can be identified within the mouse S1 by labelling the
cell soma, axons or the extracellular matrix. This strict organisation makes the rodent S1
an excellent model for discerning the proteins involved in neural circuit formation, and by
screening genetic mutants for S1 patterning defects the molecular pathway involved in
setting up neuronal circuits can be elucidated. Furthermore an understanding of these
pathways may provide insight into how neuronal networks are disrupted in human
intellectual disability.
In the first data chapter, the expression profile of three neurofilament subunits
were characterised in order to develop a method of identifying anatomical defects in barrel
morphology. The precise organisation of the rodent S1 can also be used as a method to
identify the cellular localisation of neurofilament subunits ex vivo. Neurofilaments are
polymers formed from three subunits identified by their relative molecular weight. By
using the unique patterning of S1, each neurofilament subunit shows a unique spatialtemporal
expression pattern in the somatosensory cortex. Two neurofilaments subunits;
the medium and the heavy neurofilament subunits can be used to identify TCA which can
be used as an indicator of anatomical defects in barrel patterning.
In chapter 4 neurofilament labelling was used in conjunction with other histological
techniques to investigate S1 organisation in mice lacking synapse associated protein 102
(SAP102). SAP102 is a PSD scaffolding molecule that binds to both NMDA receptor subunits
and SynGAP, a synaptic GTPase activating protein, furthermore it is associated with X-linked
mental retardation in humans (Tarpey et al., 2004; Zanni et al., 2010). Mutant mice lacking
functional NMDA receptors or PSD proteins such as SynGAP show defects in S1 pattern
formation (Barnett et al., 2006; Iwasato et al., 2000; Wijetunge, Till, Gillingwater, Ingham, &
Kind, 2008). SAP102 null mutants (SAP102-/y) have defects in synaptic plasticity and are
slow to learn on behavioural tasks (Cuthbert et al., 2007), however it is unclear how the loss
of SAP102 may disrupt neural networks. SAP102-/y were found to have a reduction in brain
mass compared to wild-type littermates, but cortical thickness and patterning of S1 is
unchanged. SAP102-/y have fewer TCA reaching the cortex compared to littermates;
furthermore SAP102-/y mutants have layer specific defects in the density of dendritic spines.
These data suggest that in the absence of SAP102 connectivity in the S1 is altered by layer
specific changes in synapses number and fewer axons innervating cortical layer IV.
In the final experimental chapter (chapter 5) the combined role of SAP102 and
Postsynaptic density protein 95 (PSD95) in S1 patterning was investigated. SAP102 and
PSD95 are the main members of the membrane-associated guanylate kinase (MAGUK)
family expressed during early cortical development. These proteins share a similar protein
structure, perform similar functions at the synapse (Elias & Nicoll, 2007) and have been
shown to compensate for each other in vitro (Elias, Elias, Apostolides, Kriegstein, & Nicoll,
2008). Genetic mutants lacking both SAP102 and PSD95 are not viable and do not survive
beyond birth (Cuthbert et al., 2007; Petrie, 2008). Therefore in order to investigate the
combined role of these proteins a novel approach was developed that utilises X-inactivation
to produce mosaic animals containing cells that lack both proteins. The distribution of cells
containing the same X-chromosome was investigated and found to be evenly distributed
throughout the cortex, demonstrating that this method could be used to investigate
allosomal genes. In mosaic animals where approximately half the cells only lack PSD95 and
the remaining cells lack both SAP102 and PSD95, double knockout cells are viable and are
equally represented in S1. These double knockout cells contribute to normally barrel
formation which suggests that SAP102 and PSD95 are not required for barrel formation
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