Coping with uncertainty:Adapting to stochasticity in an unpredictable tropical environment

Birds adjust their phenotype in response to socio-environmental changes. To understand these adjustments, aseasonal tropical areas offer an ideal setting to tease apart effects of the environment and social interactions on life history of birds. In this thesis, exploiting a stochastic, aseasonal tropical environment, we investigate if/how weather, food availability and nesting intensity are related to nest success, and whether Red-capped larks adjust their phenotype through behavioural space use and physiological adjustments of body mass and immune function to adapt to the stochastic environment. Our results show that nest predation was the single most significant cause of nest failure, but the negative correlation of nest success with flying invertebrates and rainfall, proxies of increased food availability, pointed to incidental depredation. Secondly, the number of nests found per month (nesting intensity) was the main factor influencing the home range of birds. However, Red-capped larks decreased body mass with increased food availability independent of life history stage which suggests year-round food availability. This suggests birds opt for a lean mass under good conditions probably to counter associated negative costs of higher body mass. Lastly, immune function was better explained by socio-environmental factors, while life history stage played a minor role. The stronger influence of social-environmental factors may be due to the hypothesized higher parasite diversity and pathogen pressures in tropical areas compared to temperate regions. Our study underlines the relevance of conducting more studies in aseasonal tropical areas in order to disentangle socio-environmental factors that vary in an unpredictable and unsynchronized manner

Membership as a business model: exploring reader revenue stream for media organizations in Kenya

The media landscape is facing an unprecedented crisis characterised by dwindling revenue, technological disruption, audience retention challenge, and competition from other forms of media and technology firms, with growth in digital media unable to cover the shortfall. In Kenya, the revenue crisis has morphed into the shrinking of newsrooms through massive sacking and loss of jobs, profit warnings by leading media houses and delayed payment of staff salaries. One of the main drivers of shrinking newsrooms is because of audience fragmentation and segmentation that has led to the rise of niche platforms fighting for the same revenue with mainstream media. The challenging media landscape calls for a rethink of the media business, especially on new revenue models. Media houses are now looking more to reader revenue as opposed to over-reliance on advertising revenue. The main of objective of this study was to explore membership as a revenue model for digital media in Kenya. The other specific objectives were to find out the revenue models existing in digital media in Kenya and to draw guidelines and membership incentive list for digital media in Kenya. This was an exploratory study that used qualitative method where 11 media leaders from eight media houses in Kenya were interviewed to give their views on the existing revenue model and their understanding of the viability of membership as a revenue model in digital newsrooms. From their views the study came up with a list of seven incentives media houses can use to attract and retain members. Membership being a new topic in Kenya this study relied on a document analysis of membership programs globally. Document analysis of the Membership Puzzle Project helped to illustrate the steps a media house should take while setting up a membership program using their Membership Guide

Effect of Investment Risk on Unit Trust Price Volatility Among Capital Market Authority Listed Firms in Kenya

The purpose of the study was to investigate the effect of investment risk on unit trust price volatility among CMA listed firms in Kenya. As a result of unit trust price volatility, investors are shifting to real estate and other investments with low price volatility. This makes unit trust price volatility an important issue to investigate. The unit trust price volatility is of much importance to investors, fund’s managers and government regulators. The objective that guided the study was to investigate the effect of investment risk on unit trust price volatility. A record survey sheet was used to collect secondary data using longitudinal research design. The statistical population of the study consisted of 19 Unit trusts registered by CMA 2016 and offering equity fund.  Census was taken to collect annual data for a period of 9 years from 2009 to 2017. Data presentation was done using panel plots, trend lines and distribution tables. The statistical techniques used are descriptive statistics such as Mean, median and Standard deviation. Diagnostics tests done were multicollinearity, autocorrelation, normality, Heteroskedasticity, Hausman and serial correlation.  Correlation tests, analysis of variance and panel regression analysis were also done for Inferential statistics. The hypothesis of the study was tested using panel regression analysis. The null hypothesis of the study was rejected at 5% level of significance. The results (r= -O.4366) of the study indicated that the effect of Investment risk on unit trust price volatility was negative and statistically significant at 5% levels. The overall model was tested using the F-test at 5% level of significance which resulted to the value of F (0.05,1,84) = 3.96 ≤ F (1, 83) = 19.550, p-value =0.000≤ 0.05 indicating that the model fits well. The results of the study analysis revealed that investment risk had a statistical significant effect on unit trust price volatility among CMA listed firms in Kenya for equity fund model. The coefficient of determination (R2 ) = 0.1906 which indicated that the investment risk contributes only 19.00% of the unit trust price volatility while the larger proportion is attributed to other extraneous variables. The model can be used for unit trust price volatility prediction though on a low scale. The study made the following recommendations; CMA regulate and inspect the financial stability policies governing unit trusts, unit trust firms to pay the investors in time and improve on financial stability, reduce on the operation costs and control operation systems of unit trusts. On policy implication, the government should review the CMA act to give the authority the inspection mandate on the unit trust to make them efficient and conform to financial international standards to be in line with the economic pillar of vision 2030. Keywords: Investment risk, unit trust price volatility DOI: 10.7176/RJFA/10-8-05 Publication date: April 30th 201

Aquatic toxicity of one dimensional carbon nanomaterials

The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file.Title from PDF of title page (University of Missouri--Columbia, viewed on October 28, 2010).Thesis advisor: Dr. Baolin Deng.Vita.Ph. D. University of Missouri--Columbia 2010.This study determined the toxicity of one dimensional carbon nanomaterials (CNMs) to amphipods, midge, oligochaetes and juvenile mussels in water and sediment. As-produced or modified carbon nanotubes (CNTs) and silicon carbide nanowires (SiCNW) were selected to represent CNMs. Sediment tests were conducted for 10-d with SiCNW and for 14- and 28-d with CNTs using amphipods. Sonicated SiCNW in water were toxic to the amphipods but not to the midge, oligochaetes or mussels and non-sonicated SiCNW in water were not toxic to amphipods. Sonicated or non-sonicated CNT in water were toxic to all four benthic invertebrates. CNTs spiked into sediments were mildly toxic to amphipods reduced in toxicity. During exposures, the test organisms were coated with the CNMs and the organisms also ingested and accumulated these CNMs in their guts. Overall, the toxicity of the CNMs (CNTs or SiCNW) appears to be the effect of the coating of respiratory surfaces or the blocking of the digestive tract of the exposed benthic invertebrates. The metals dissolution from the as-produced CNTs could also have contributed to the toxicity.Includes bibliographical reference

Effects of strength-training trials for children and adolescents with spastic cerebral palsy: a systematic review

OBJECTIVE: To evaluate the effects of strength-training on lower limb muscles and motor activity among children and adolescents with spastic Cerebral Palsy. METHODS: A comprehensive search of full text published studies in English was performed. Electronic databases were searched with no limit for year of publication. Terms used included: exercise, children, youth, disability, treatment, strength training, spastic cerebral palsy, muscle strength, training program, therapeutic exercise, gait training, and physical function. Reference lists of retrieved articles were also examined to identify additional studies. To be included, studies had to be: randomised controlled trials evaluating strength training outcomes on children and adolescents with spastic CP. Those with intellectual disability were excluded. Evaluation for quality: Trials were rated for methodological quality using the PEDro scale independently by the 2 researchers. RESULTS: Of 4 selected trials, 1 an abstract was excluded, 3 full articles were included. Trials methodological quality ranged from 6 to 8 on PEDro scale. Two studies reported significant muscle strength changes following strength training, with effect sizes ranging from d equal to 1.17 to 1.78 and another reported improved gait and perceived body image. CONCLUSION: Trials demonstrate that strength-training improves strength of targeted muscle and motor functioning. More rigorous trials on larger samples should evaluate the impact of specificity in strength-training and cost-effectiveness of programs

Physical activity levels among young people with physical disabilities in selected high schools in Kenya and their perceived barriers and facilitators to participation

Purpose: To determine the levels of and potential contributing factors to participation in physical activity among young people with physical disabilities attending high school in Kenya. Methods: A cross-sectional survey, using a pre-piloted and validated self-administered questionnaire, was carried out in a purposively selected sample of 234 young people with physical disabilities drawn from three inclusive high schools in Kenya. The questionnaire comprising outcome measures for physical activity levels, barriers, and facilitators to physical activity participation was administered to the young people. Data was analyzed using the Statistical Package for Social Sciences (SPSS) and both descriptive and inferential statistics were done. Results: Almost half of the children in the sample were inactive. Key barriers to physical activity were found to be: fear avoidance and disability, lack of time and the need to rest. Finding ways to exercise that are enjoyable, and not being in good health were associated significantly to gender (p<0.05). Likewise, age was significantly associated with gaining peer acceptance, as was encouragement from family and having disability (p<0.05). Conclusion: The results indicate there is a need, for activity counselling and provision of local disability-friendly and/or conducive environments to increase physical activity participation in this sample. All stakeholders should be enlisted in making recommendations and designing physical activity programmes for young people with disabilities in their schools

Security Analysis of WPA2

Wireless networks provide convenient and low cost mechanism for connecting network devices. They are ideal since they do not require physical connections .They therefore helps overcome the port limitations of the physical hardware. Any device that has radio receiver can detect these wireless signals as the wireless router transmits the signals uniformly in all directions.  The ease with which connections can be established exposes wireless networks to many attacks. The authentication protocols have been developed to deter any illicit access to wireless networks, Wi-Fi Protected Access version 2 being one of them. The objective of this research paper was to demonstrate that one can still break the Confidentiality, Integrity and Availability (CIA) triad in the presence of this authentication protocol. The set up was implemented in Ubuntu 12.04 operating system using Ettercap, File2air, Khexedit , Wireshark and Airodump-ng from Aircrack-ng suite. The results indicated that WPA2 does not actually protect data in transit in wireless networks, and therefore there is need to explore other technologies that can secure wireless networks. Keywords:WPA2, CIA Triad, Wireless, Security