1,545 research outputs found
Glenoid failure in Total Shoulder Arthroplasty
Compared to hip and knee, anatomic shoulder arthroplasty is relatively poorly understood,
underdeveloped and reported loosening rates are very high, the common cause of failure
being glenoid aseptic loosening.
The aim of this thesis was first to establish in-vitro and in-vivo CT protocols allowing direct
monitoring of glenoid fixation and aseptic loosening and secondly to identify key elements
of the procedure that could improve results of prosthetic surgery.
First, in-vitro, the ASTM standard method for evaluating loosening of glenoid implants was
modified, so that, with the use of CT-scans at regular interval basis, it allows the direct
monitoring of the failure observed in the laboratory setting. The failure was observed at the
cement-implant interface and progressed from the edges of the implants, both superior and
inferior, towards the keel.
Secondly, an in-vivo CT protocol was established that eliminates most of the metallic
artefacts caused by the humeral head and consequently enhances the visualisation of the
radiolucent lines and osteolysis around the glenoid. The link between radiological lucencies
and aseptic loosening was confirmed first in a study including 68 cases using this CT
protocol, which confirmed the progression of the lucencies over time, and secondly, by the
use of Spect-CT.
The 3-dimensional spatial (mal)position of the glenoid component and the resulting
consequences were analysed in three additional studies. The effect of malposition on clinical
results and radiological lucencies; the relationship to the preoperative eroded glenoid and the
relationship to polyethylene wear were all investigated. These studies stressed how
inaccurately the glenoid components are positioned in clinical practise and that this
inaccuracy has a detrimental effect on polyethylene wear; aseptic loosening and ultimately
on clinical outcome.
Future work should focus on establishing the optimal position of the glenoid implant, and
how to achieve this optimal placement in surgical practise
Effect Of Dividend On Share Price Volatility In Frontier Exchanges: Kenya’s Perspective
Equity investors are faced by very pertinent decisions in the course of their portfolio management such as how to manage the share price volatility. While the extent to which dividend influences volatility is not contentious, the most suitable proxy between the two measures: dividend yield or pay-out is especially in a frontier market is. This study using prices and company performance data of firms listed in Nairobi Stock Exchange performed a cross-sectional analysis for the period 2013-2014. Significant positive association between dividend and share price volatility has been found. Multicollinearity is present between dividend yield and dividend payout which is extended by low R2 when yield is regressed against price volatility. The study not only confirms that dividend payout as a predominant determinant but the only credible determinant (as a proxy variable for dividends) of share price volatility in a frontier market. Evidence deduced confirms congruence to dividend relevance accompanied by weak market efficiency. Keywords: share price volatility; dividend; dividend pay-out; dividend yield; proxy variable; technical and fundamental analysi
New species and taxonomic changes in the Grevillea thelemanniana Group (Proteaceae: Grevilleoideae: Hakeinae) from south-west Western Australia
Four species are added to the Grevillea thelemanniana Group, the constituency of which is discussed in light of recent phylogenetic analyses. Two new species are described. Grevillea cooljarloo Keighery and Olde was previously included by some in Grevillea preissii Meisn. subsp. preissii or as G. pinaster divided-leaf form, and is presently known informally as Grevillea thelemanniana subsp. Cooljarloo (B.J. Keighery 28B) by the Western Australian Herbarium. Grevillea gillingarra Olde and Keighery has previously been confused with G. thelemanniana Hügel ex Endl. Grevillea preissii subsp. glabrilimba Olde and Marriott is here recognised at specific rank, as G. glabrilimba (Olde and Marriott) Olde. Grevillea preissii is more narrowly circumscribed, in line with the original concept sensu Meisner (1845), without subspecies. A photo of the Blaschka glass model of Grevillea preissii is included with permission. The historical confusion between G. thelemanniana and G. preissii is revisited. Grevillea variifolia subsp. bundera Keighery is recognised at species-level as G. bundera (Keighery) Olde and Keighery. A conservation assessment for all taxa is provided and a key to the revised Thelemanniana Group, as currently accepted, is supplied
Determinants of Foreign Direct Investment Growth: Kenya’s Manufacturing Sector
The FDI indicators in Kenya show a mixed signal and although institutional indexes for Kenya have been worsening over the years, foreign direct investment inflows (FDI) though sluggish has been on the rise. While many theories of FDI have been put forward, mostly ownership, location and internationalization (OLI), the extent to which institutional determinants influence growth of FDI in the Kenyan manufacturing sector has not gotten adequate attention. The combination of institutional determinants and OLI framework in determining flows of FDI has been avoided in this sector. This study using FDI inflows in the Kenyan manufacturing sector and governance indicators data performed a cross-sectional analysis for the period 2009-2013. The findings indicated significant positive relationship between governance and FDI growth which implies that governance determines growth of FDI in the Kenyan manufacturing sector. The evidence presented confirms that a good political climate and good corporate governance are important for foreign investment to flow into a Country. Keywords: foreign direct investment; corporate governance; political risk; manufacturing secto
Effect of Market Structure on Financial Performance of Deposit Taking Microfinance Institutions in Nairobi City County, Kenya
The purpose of this study was to investigate the effect of market structure on financial performance of Deposit Taking Microfinance Institutions (DTMIs) in Nairobi City County, Kenya. Mixed method of research design was used and data was collected using questionnaires and secondary data collection sheet. Target population was the 12 registered DTMIs in Kenya from which sixty (60) portfolio managers and credit officers were randomly selected to form the sample size. Cronbach test of 0.809 was obtained and validity of the research instruments was ensured through content, criterion and construct validity testing. Data was analyzed using descriptive statistics and inferential statistics which included correlation analysis, ANOVA and multiple regression analysis. The study established a positive statistically significant relationship between market structure and financial performance. The market structure explained 62.2% of the changes in the financial performance DTMIs in Kenya. It’s recommended that, market share should be strengthened in financial institutions to enable them proactively increase their deposit accounts and number of clients. Keywords: market structure, financial performance, Deposit Taking Microfinance Institutions (DTMIs
Redefining Pedestrian Infrastructure
Urban spaces are seeing a poor adaptability of roads and pedestrian traffic to coexist without conflict. This can be seen by looking into vehicle versus pedestrian accidents and their causes, what interventions are currently in place, and how urban sprawl has played a part in this crisis. In addition, case studies focusing on various urban design plans will be evaluated. Finally, it will be discussed how these issues can be addressed and what implementations can be made architecturally to alleviate the strain between vehicles and pedestrians in urban spaces.https://digitalscholarship.unlv.edu/arch_grad_capstones/1052/thumbnail.jp
Effect of Risk Management Practices on Financial Performance in Kenya Commercial Banks
The purpose of this study was to investigate the effect of risk management practices on Commercial Banks performance. Mixed method of research design was used and data was collected using questionnaires and interview schedules. Target population was 43 licensed Commercial Banks in Kenya from which one hundred and thirty three (133) managers were randomly selected to form sample size. Cronbach test of 0.874 was obtained and validity of the research instruments was ensured through content, criterion and construct validity testing. Data was analyzed using descriptive statistics and inferential statistics which included correlation analysis, bivariate regression analysis and multiple regression analysis. The study established a positive statistically significant relationship between risk management practices and financial performance. The risk management practices explained 62.2% of the changes in the financial performance in commercial banks in Kenya. It’s recommended that, risk management framework should be adopted in financial institutions to enable them proactively mitigate risks. Keywords: Risk management practices, financial performance, Commercial Banks
Effect of Entrepreneurial Orientation on the Growth of women Micro and Small Enterprises in Trans Nzoia County, Kenya
The MSEs are globally the focus of policy makers due to their ability to distribute incomes in both rural and urban areas for poverty reduction. Entrepreneurial orientation is one of the major determinant of women MSE business start up, growth and graduation in to medium and large scale enterprises. The objective of the study was to determine the effect of Entrepreneurial Orientation on the growth of women owned Micro and Small Enterprises in Trans Nzoia County, Kenya. Questionnaires, interview schedules and observation methods were used to collect data from 170 sampled women group MSE owner managers under Women Enterprise Fund subsidized entrepreneurial credit scheme in Trans-Nzoia County who were licensed by the county revenue department and have been in business between 2009 and 2015. Growth was measured in terms of change in sales revenue, profit and number of employees before and after Women Enterprise Fund intervention measures. The data was summarised and analysed using descriptive and inferential statistics of frequency distribution, mean, percentages, correlation and linear regression. The study found out that Entrepreneurial orientation had statistically significant relationship with growth of women MSEs at 0.05 level of significance. It was recommended that the Government in conjunction with County Governments should nurture an entrepreneurial culture through continuous technology upgrading courses in National polytechnics in addition to experiential learning through exchange visits and attendance of national and international trade fairs. The government should provide modern business infrastructure to women Micro and MSEs in order to spur their meaningful and faster growth. To attain production and marketing economies of scale, clustering of women MSEs with subsequent subcontracting arrangements with medium and large enterprises was also recommended
Recommended from our members
Mapping Milky Way Dust in 3D With Stellar Photometry
I present a three-dimensional map of interstellar dust reddening, covering three-quarters of the sky out to a distance of several kiloparsecs, based on Pan-STARRS 1 and 2MASS photometry. The map reveals a wealth of detailed structure, from filaments to large cloud complexes. The map has a hybrid angular resolution, with most of the map at an angular resolution of 3.4′ to 13.7′ , and a maximum distance resolution of ∼25%. The three-dimensional distribution of dust is determined in a fully probabilistic framework, yielding the uncertainty in the reddening distribution along each line of sight, as well as stellar distances, reddenings and classifications for 800 million stars detected by Pan-STARRS 1. The method developed here compares observed stellar photometry with empirical stellar templates, incorporating prior knowledge about the structure of the Galaxy.
I validate the per-star reddening estimates by comparison with reddening estimates for stars with both SDSS photometry and SEGUE spectral classifications, finding per-star agreement to within ∼0.15 mag out to a stellar E(B−V) of 1 mag. I demonstrate the consistency of the resulting reddening estimates with those of two-dimensional emission-based maps of dust reddening. In particular, I find agreement with the Planck τ353 GHz-based reddening map to within 0.05 mag in E(B−V) to a depth of 0.5 mag, and explore systematics at reddenings less than E(B−V) ≈ 0.08 mag. I compare the 3D map developed here to two existing three-dimensional dust maps, by Marshall et al. (2006) and Lallement et al. (2013), exploring the strengths and weaknesses of the different 3D mapping methods. The map presented here has better angular resolution than both 3D maps compared, and it has better distance resolution than Marshall et al. (2006) within ∼3 kpc, but shows radial “finger-of-God” features not contained in Lallement et al. (2013).
The map can be queried or downloaded at http://argonaut.skymaps.info. I expect the three-dimensional reddening map presented here to find a wide range of uses, among them correcting for reddening and extinction for objects embedded in the plane of the Galaxy, studies of Galactic structure, calibration of future emission-based dust maps and determining distances to objects of known reddening. The method we present is not limited to the passbands of the Pan-STARRS 1 and 2MASS surveys, but may be extended to incorporate photometry from other optical and near-infrared surveys, such as WISE, Spitzer GLIMPSE, UKIDSS, SDSS (where available), and in the future, LSST and Gaia. The method can also be naturally extended to stellar kinematic data, such as that soon to be released by Gaia.Astronom
Merleau-Ponty and neuroaesthetics: Two approaches to performance and technology
This is an Author's Accepted Manuscript of an article published in Digital Creativity, 23(3-4), 225 - 238, 2012. Copyright @ 2012 Taylor & Francis, available online at: http://www.tandfonline.com/10.1080/14626268.2012.709941.Assisted by the rapid growth of digital technology, which has enhanced its ambitions, performance is an increasingly popular area of artistic practice. This article seeks to contextualise this within two methodologically divergent yet complimentary intellectual tendencies. The first is the work of the philosopher Merleau-Ponty, who recognised that our experience of the world has an inescapably ‘embodied’ quality, not reducible to mental accounts, which can be vicariously extended through specific instrumentation. The second is the developing field of neuroaesthetics; that is, neurological research directed towards the analysis, in brain-functional terms, of our experiences of objects and events which are culturally deemed to be of artistic significance. I will argue that both these contexts offer promising approaches to interpreting developments in contemporary performance, which has achieved critical recognition without much antecedent theoretical support
- …