Asset Management in Electricity Transmission Utilities: Investigation into Factors Affecting and their Impact on the Network

This thesis draws on techniques from Management Science and Artificial Intelligence to explore asset management in electricity transmission enterprises. In this research, factors that influence policies and practices of asset management within electricity transmission enterprises have been identified, in order to examine their interaction and how they impact the policies, practices and performance of transmission businesses. It has been found that, while there is extensive literature on the economics of transmission regulation and pricing, there is little published research linking the engineering and financial aspects of transmission asset management at a management policy level. To remedy this situation, this investigation has drawn on a wide range of literature, together with expert interviews and personal knowledge of the electricity industry, to construct a conceptual model of asset management with broad applicability across transmission enterprises in different parts of the world. A concise representation of the model has been formulated using a Causal Loop Diagram (CLD). To investigate the interactions between factors of influence it is necessary to implement the model and validate it against known outcomes. However, because of the nature of the data (a mix of numeric and non-numeric data, imprecise, incomplete and often approximate) and complexity and imprecision in the definition of relationships between elements, this problem is intractable to modelling by traditional engineering methodologies. The solution has been to utilise techniques from other disciplines. Two implementations have been explored: a multi-level fuzzy rule-based model and a system dynamics model; they offer different but complementary insights into transmission asset management. Each model shows potential to be used by transmission businesses for strategic-level decision support. The research demonstrates the key impact of routine maintenance effectiveness on the condition and performance of transmission system assets. However, performance of the transmission network, is not only related to equipment performance, but is a function of system design and operational aspects, such as loading and load factor. Type and supportiveness of regulation, together with the objectives and corporate culture of the transmission organisation also play roles in promoting various strategies for asset management. The cumulative effect of all these drivers is to produce differences in asset management policies and practices, discernable between individual companies and at a regional level, where similar conditions have applied historically and today

Public health equity in refugee situations

Addressing increasing concerns about public health equity in the context of violent conflict and the consequent forced displacement of populations is complex. Important operational questions now faced by humanitarian agencies can to some extent be clarified by reference to relevant ethical theory. Priorities of service delivery, the allocation choices, and the processes by which they are arrived at are now coming under renewed scrutiny in the light of the estimated two million refugees who fled from Iraq since 2003

An exploration of the use of simple statistics to measure consensus and stability in Delphi studies

<p>Abstract</p> <p>Background</p> <p>The criteria for stopping Delphi studies are often subjective. This study aimed to examine whether consensus and stability in the Delphi process can be ascertained by descriptive evaluation of trends in participants' views.</p> <p>Methods</p> <p>A three round email-based Delphi required participants (n = 12) to verify their level of agreement with 8 statements, write comments on each if they considered it necessary and rank the statements for importance. Each statement was analysed quantitatively by the percentage of agreement ratings, importance rankings and the amount of comments made for each statement, and qualitatively using thematic analysis. Importance rankings between rounds were compared by calculating Kappa values to observe trends in how the process impacts on subject's views.</p> <p>Results</p> <p>Evolution of consensus was shown by increase in agreement percentages, convergence of range with standard deviations of importance ratings, and a decrease in the number of comments made. Stability was demonstrated by a trend of increasing Kappa values.</p> <p>Conclusion</p> <p>Following the original use of Delphi in social sciences, Delphi is suggested to be an effective way to gain and measure group consensus in healthcare. However, the proposed analytical process should be followed to ensure maximum validity of results in Delphi methodology for improved evidence of consensual decision-making.</p

In vivo kinetic approach reveals slow SOD1 turnover in the CNS

Therapeutic strategies that target disease-associated transcripts are being developed for a variety of neurodegenerative syndromes. Protein levels change as a function of their half-life, a property that critically influences the timing and application of therapeutics. In addition, both protein kinetics and concentration may play important roles in neurodegeneration; therefore, it is essential to understand in vivo protein kinetics, including half-life. Here, we applied a stable isotope-labeling technique in combination with mass spectrometric detection and determined the in vivo kinetics of superoxide dismutase 1 (SOD1), mutation of which causes amyotrophic lateral sclerosis. Application of this method to human SOD1-expressing rats demonstrated that SOD1 is a long-lived protein, with a similar half-life in both the cerebral spinal fluid (CSF) and the CNS. Additionally, in these animals, the half-life of SOD1 was longest in the CNS when compared with other tissues. Evaluation of this method in human subjects demonstrated successful incorporation of the isotope label in the CSF and confirmed that SOD1 is a long-lived protein in the CSF of healthy individuals. Together, the results of this study provide important insight into SOD1 kinetics and support application of this technique to the design and implementation of clinical trials that target long-lived CNS proteins

Effects of antiplatelet therapy on stroke risk by brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases: subgroup analyses of the RESTART randomised, open-label trial

Background Findings from the RESTART trial suggest that starting antiplatelet therapy might reduce the risk of recurrent symptomatic intracerebral haemorrhage compared with avoiding antiplatelet therapy. Brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases (such as cerebral microbleeds) are associated with greater risks of recurrent intracerebral haemorrhage. We did subgroup analyses of the RESTART trial to explore whether these brain imaging features modify the effects of antiplatelet therapy

Uncoordinated Transcription and Compromised Muscle Function in the Lmna-Null Mouse Model of Emery-Dreifuss Muscular Dystrophy

LMNA encodes both lamin A and C: major components of the nuclear lamina. Mutations in LMNA underlie a range of tissue-specific degenerative diseases, including those that affect skeletal muscle, such as autosomal-Emery-Dreifuss muscular dystrophy (A-EDMD) and limb girdle muscular dystrophy 1B. Here, we examine the morphology and transcriptional activity of myonuclei, the structure of the myotendinous junction and the muscle contraction dynamics in the lmna-null mouse model of A-EDMD. We found that there were fewer myonuclei in lmna-null mice, of which ∼50% had morphological abnormalities. Assaying transcriptional activity by examining acetylated histone H3 and PABPN1 levels indicated that there was a lack of coordinated transcription between myonuclei lacking lamin A/C. Myonuclei with abnormal morphology and transcriptional activity were distributed along the length of the myofibre, but accumulated at the myotendinous junction. Indeed, in addition to the presence of abnormal myonuclei, the structure of the myotendinous junction was perturbed, with disorganised sarcomeres and reduced interdigitation with the tendon, together with lipid and collagen deposition. Functionally, muscle contraction became severely affected within weeks of birth, with specific force generation dropping as low as ∼65% and ∼27% of control values in the extensor digitorum longus and soleus muscles respectively. These observations illustrate the importance of lamin A/C for correct myonuclear function, which likely acts synergistically with myotendinous junction disorganisation in the development of A-EDMD, and the consequential reduction in force generation and muscle wasting

A systematic review of longitudinal studies on the association between depression and smoking in adolescents

<p>Abstract</p> <p>Background</p> <p>It is well-established that smoking and depression are associated in adolescents, but the temporal ordering of the association is subject to debate.</p> <p>Methods</p> <p>Longitudinal studies in English language which reported the onset of smoking on depression in non clinical populations (age 13-19) published between January 1990 and July 2008 were selected from PubMed, OVID, and PsychInfo databases. Study characteristics were extracted. Meta-analytic pooling procedures with random effects were used.</p> <p>Results</p> <p>Fifteen studies were retained for analysis. The pooled estimate for smoking predicting depression in 6 studies was 1.73 (95% CI: 1.32, 2.40; p < 0.001). The pooled estimate for depression predicting smoking in 12 studies was 1.41 (95% CI: 1.21, 1.63; p < 0.001). Studies that used clinical measures of depression were more likely to report a bidirectional effect, with a stronger effect of depression predicting smoking.</p> <p>Conclusion</p> <p>Evidence from longitudinal studies suggests that the association between smoking and depression is bidirectional. To better estimate these effects, future research should consider the potential utility of: (a) shorter intervals between surveys with longer follow-up time, (b) more accurate measurement of depression, and (c) adequate control of confounding.</p

The emerging dental workforce: why dentistry? A quantitative study of final year dental students' views on their professional career

<p>Abstract</p> <p>Background</p> <p>Dental graduates are joining a profession experiencing changes in systems of care, funding and skill mix. Research into the motivation and expectations of the emerging workforce is vital to inform professional and policy decisions. The objective of this research was to investigate final year dental students' perceived motivation for their choice of career in relation to sex, ethnicity and mode of entry.</p> <p>Methods</p> <p>Self-administered questionnaire survey of all final year dental students at King's College London. Data were entered into SPSS; statistical analysis included Chi Squared tests for linear association, multiple regression, factor analysis and logistic regression.</p> <p>Results</p> <p>A response of 90% (n = 126) was achieved. The majority were aged 23 years (59%), female (58%) and Asian (70%). One in 10 were mature students. Eighty per cent identified 11 or more 'important' or 'very important' influences, the most common of which were related to features of the job: 'regular working hours' (91%), 'degree leading to recognised job' (90%) and 'job security' (90%). There were significant differences in important influences by sex (males > females: 'able to run own business'; females > males: 'a desire to work with people'), ethnic group (Asians > white: 'wish to provide public service', 'influence of friends', 'desire to work in healthcare', having 'tried an alternative career/course' and 'work experience') and mode of entry (mature > early entry: 'a desire to work with people'). Multivariate analysis suggested 61% of the variation in influences is explained by five factors: the 'professional job' (31%), 'healthcare-people' (11%), 'academic-scientific' (8%), 'careers-advising' (6%), and 'family/friends' (6%). The single major influence on choice of career was a 'desire to work with people'; Indian students were twice as likely to report this as white or other ethnic groups.</p> <p>Conclusion</p> <p>Final year dental students report a wide range of important influences on their choice of dentistry, with variation by sex, ethnicity and mode of entry in relation to individual influences. Features of the 'professional job', followed by 'healthcare and people' were the most important underlying factors influencing choice of career.</p

The SUN Protein Mps3 Is Required for Spindle Pole Body Insertion into the Nuclear Membrane and Nuclear Envelope Homeostasis

The budding yeast spindle pole body (SPB) is anchored in the nuclear envelope so that it can simultaneously nucleate both nuclear and cytoplasmic microtubules. During SPB duplication, the newly formed SPB is inserted into the nuclear membrane. The mechanism of SPB insertion is poorly understood but likely involves the action of integral membrane proteins to mediate changes in the nuclear envelope itself, such as fusion of the inner and outer nuclear membranes. Analysis of the functional domains of the budding yeast SUN protein and SPB component Mps3 revealed that most regions are not essential for growth or SPB duplication under wild-type conditions. However, a novel dominant allele in the P-loop region, MPS3-G186K, displays defects in multiple steps in SPB duplication, including SPB insertion, indicating a previously unknown role for Mps3 in this step of SPB assembly. Characterization of the MPS3-G186K mutant by electron microscopy revealed severe over-proliferation of the inner nuclear membrane, which could be rescued by altering the characteristics of the nuclear envelope using both chemical and genetic methods. Lipid profiling revealed that cells lacking MPS3 contain abnormal amounts of certain types of polar and neutral lipids, and deletion or mutation of MPS3 can suppress growth defects associated with inhibition of sterol biosynthesis, suggesting that Mps3 directly affects lipid homeostasis. Therefore, we propose that Mps3 facilitates insertion of SPBs in the nuclear membrane by modulating nuclear envelope composition