An examination of postharvest techniques to enable seafreight export of feijoa (Acca sellowiana [O.Berg.] Burret) : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Food Technology at Massey University, Manawatu Campus, Palmerston North, New Zealand

Export of feijoa (Acca sellowiana [O.Berg.] Burret) to the main markets in Europe, Asia and North America is currently by airfreight that is not only expensive but rather unsustainable as the industry expands. With the ongoing breeding works and expansions of plantings, growers will eventually have to seek for an economic mode of transport. As is the case with kiwifruit, apples, avocadoes, and squash, seafreight will provide an alternative option that is both cheaper and accommodates large fruit volumes. The short storage life of feijoa, however, is likely to pose a challenge to seafreight (that requires at least 6 weeks of storage) if appropriate postharvest techniques are not identified to extend storage life. Feijoa stores for about 4 weeks at 4 °C after which it becomes overripe, loses flavour, and develops chilling injury and internal browning. This study was undertaken to examine potential postharvest techniques that could extend storage life and maintain quality of feijoa. The postharvest techniques investigated were temperature and relative humidity management, harvest timing, step down conditioning, intermittent warming, chlorophyll fluorescence and development of non-destructive grading tools. The varieties used in this study were ‘Kakariki’, ‘Wiki Tu’ and ‘Triumph’ that were stored for 8 weeks under various conditions. To assess the effects of temperature and relative humidity in storage, ‘Kakariki’, ‘Wiki Tu’ and ‘Triumph’ were stored at 1 °C (85% RH) and 4 °C (88% RH). These conditions were set to result in equal water vapour pressure deficits at both temperatures. The effects of RH on feijoa quality during 8 weeks storage were tested by using a polyethylene liner (polyliner) to cover the fruit in each tray, for half of the treatments. Despite good retention of some attributes indicating quality (firmness and skin colour) for up to 8 weeks at 1 °C, many fruit developed chilling injury making it unsaleable and therefore causing huge losses. At both 4 °C and 1 °C the use of a polyliner resulted in reduced water loss, suggesting polyliners may be beneficial for feijoa storage. Given the chilling injury results, it is imperative to consider treatments that may reduce chilling injury and yet maintain fruit quality. To alleviate chilling injury and extend storage life of ‘Kakariki’, 2 harvesting times (early (H1) and commercial (H2)), 2 storage temperatures (2 °C and 4 °C) and three conditioning treatments (single step down, [6 d at 9 °C then moved to 2 °C or 4 °C ], double step down [3 d at 9 °C , 3 d at 6 °C then moved to 2 °C or 4 °C] and ‘no conditioning’ control [stored direct to 2 °C or 4 °C]) were established. Results showed that early harvested fruit had lower chilling injury incidence and retained more quality attributes thereby providing a possibility of extending Kakariki’ feijoa storage life. There was no evidence for a difference in quality arising from storage at 2 °C or 4 °C but it was evident that single or double step down conditioning simply allowed an extended period of postharvest ripening because of the 6 d delay in reaching the more appropriate storage temperature of 2 °C or 4 °C. This led to faster deterioration of fruit. Therefore, it is advisable to rapidly cool feijoa soon after harvest to reduce metabolism and ripening; but then sell the fruit before they develop CI. To assess the effects of intermittent warming (IW) on improving quality of ‘Triumph’ fruit. Three (3) intermittent warming conditions were tested (IW from 4 °C to 20 °C for 1 d after every 6 d storage, IW from 4 °C to 20 °C for 1 d after every 10 d storage and control) and stored at 4 °C for 6 weeks. Chlorophyll fluorescence was used as a non-destructive tool to assess quality. The results showed that intermittent warming just like conditioning treatments, accelerated ripening leading to faster deterioration. A decline in quantum yield (Fv/Fm) was observed during storage in the absence of CI. This suggests that it is linked to loss of chlorophyll content and chloroplast membrane injury associated with photosystem II (PSII) as feijoa ripened. The continuous decline in quantum yield (Fv/Fm) offers potential for a non-destructive technique to assess feijoa ripeness and could therefore be used in a cool store to detect batches of fruit that are ripening more quickly for immediate sales or those ripening slowly that may be more suited to export or long storage. To re-evaluate the internal maturity/ripeness scale developed by scanned images of ‘Kakariki’, ‘Wiki Tu’ and ‘Triumph’ varieties from at harvest through storage were assessed against the PFR scale. The results showed that the PFR scale worked well for maturity assessment of ‘Kakariki’, ‘Wiki Tu’ and ‘Triumph’ varieties at harvest, despite their quite different internal anatomy. The same scale was also appropriate for each variety as a post-storage ripeness indicator. Evidence also suggested that one new step was required an internal maturity rating of 1.5. The problem was that fruit at stage 1 could be immature (and not ripen during storage) or mature. This new stage was used to describe fruit showing the first signs of locular gel clearing, suggesting that ripening was definitely underway. Firmness (non-destructively assessed) at harvest was correlated with quality after storage and therefore showed potential to predict fruit ripening behaviour in storage. This implies, that firmness could be used non-destructively in sorting lines to select firm fruit for long storage or soft fruit for immediate consumption. Based on these findings’, storage life of ‘Kakariki’, ‘Wiki Tu’ and ‘Triumph’ feijoa could not be reliably extended beyond 4 to 6 weeks and therefore seafreight export is still risky. The wide range of maturity variation within any batch of harvested feijoas accounts for much of this risk. Future research should focus on finding a rapid, non-destructive technique that can detect the new internal maturity/ripeness rating 1.5. This would assist growers to grade early harvested fruit and select mature but longer-storing fruit for export

Capital Structure and Firm Performance in Nigerian-Listed Companies

a number of business failures have not been reported in Nigeria arising from inability to payback nor does service debts .This paper empirically investigate the relationship between capital structure and firm performance in the Nigerian listed firms. A sample of 30listed firms out of a population of 173 were examined from 2005 to 2014 using multiple regression tools. Two hypotheses were formulated and tested using descriptive statistics and an econometric panel data technique to analyze the gathered data. An insignificantly negative correlation was found between financial leverage and ROA on one hand and a significantly negative relationship between debt/equity mix and ROE on the other hand. It is therefore recommended that firms should use long term liabilities to finance firm’s activities and mix debt/equity appropriately by ensuring that debt financing ratio is lower to enhance corporate performance and survival

Does Liquidity Management Affect Profitability in Selected Nigerian-Quoted Manufacturing Firms?

This study examined the nexus between liquidity management and profitability in selected Nigerian-quoted manufacturing firms. Many business failures have been recorded over the years due to inability to balance the link between liquidity and profitability. Descriptive research design was employed to analyze the data gathered from 2004 to 2014. The study found a positive relationship between credit policy, return on equity and return on capital employed. It equally found that operating cash flow and cash conversion cycle are negatively related to all the metrics of profitability. The study therefore recommends among others, that managers should strive to achieve a reasonable level of profit to optimize shareholders’ wealth and keep the firms in business. Also, managers should effectively manage account receivables and inventory at optimal level to avoid tie down liquid assets unnecessarily. Investors should pay close attention to firms’ operational cash flow in order to access their true state before committing their funds

Modelling Volatility Persistence and Asymmetry with Structural Break: Evidence from the Nigerian Stock Market

Abstract: This study contributes to existing literature on the Nigerian stock market by modelling the persistence and asymmetry of stock market volatility taking into account structural break. It utilises returns generated from data on monthly all-share index from January 1985 to December 2014. After identifying structural break in the return series, the study splits the sample period into pre-break period (January 1985 – November 2008) and post-break period (January 2009 – December 2014). Using the symmetric GARCH model, the study shows that the sum of ARCH and GARCH coefficients is higher in the pre-break period compared to the post-break period, thus indicating that persistence of shock to volatility is higher before structural break in the market. The asymmetric GARCH model provides no evidence of asymmetry as well as leverage effect with or without accounting for structural break in the Nigerian stock market. This study concludes that the Nigerian stock market is characterised by inefficiency, high degree of uncertainty and non-asymmetric volatility.Keywords: Persistence, asymmetry, stock market volatility, structural brea

Effect of Agency Costs on Executive Compensation in South African Commercial Banks

This study examines the roles of agency cost (monitoring and bonding cost) on compensation of managers with a view from the managerial-power approach to agency cost. We modelled managers’ compensation and agency cost of banks to emphasise the potential influence of agency cost on managers’ compensation. A Panel Generalised Least Square model was estimated on four largely-controlled commercial banks in South Africa over the period 2010-2015. The result shows that shareholders’ fund, management share option, monitoring and bonding cost were strongly significant in explaining the managers’ compensation in the banks. Therefore, in the South African banking sector, compensation of managers should be based on their managerial power and not only on the principle of optimal-contracting. It is recommended, among others, that monitoring and bonding costs in the South African banks should be re-emphasised and strictly committed to. This should be so because there are direct effects of these costs on managers’ compensation which might be the reason for the persistent agency problem in the banks

Influence of Father Absence on Academic Performance of Secondary School Students in Keiyo Sub-County, Kenya

The presence or absence of significant person in one's life influences feelings and subsequent behaviour of individuals. This study was designed to investigate the effects of father absence on academic performance among secondary school students. The study sought to achieve the following specific objectives: To investigate the difference between academic performance of father absent and father present students; To determine the difference between academic performance of father absent and father present boys; and to establish the difference between academic performance of father absent and father present girls. The study was based on Carl Rogers self-theory. Purposive sampling was used to select students from father absent families while random sampling was used to select the students from father present families. An average of three end term examinations served as an index of academic performance. Data was analyzed using descriptive statistics. Inferential statistics was also used to compare the results specifically students t-test. The findings revealed that students from father absent family perform poorly in school as compared to their counterparts from intact homes. The mean of students from father absent family was 10.66 while that of students from father present family was 20.178. This meant that there was a significant difference in academic performance of father absent and father present students.It was also established that boys from father absent family performed poorly in school as compared to their counterparts from father present homes. The study established that girls from father absent family performed poorly in school as compared to their counterparts from father present homes. The study recommends that fathers as well as mothers should have the right to some time off work to visit the school and that parents should spare enough time to make meaningful relationships with children that can enhance academic performance

Efficiency of Foreign Exchange Markets in Sub-Saharan Africa in the Presence of Structural Break: A Linear and Non-Linear Testing Approach

This study examines the efficiency of foreign exchange (forex) market of 10 selected countries in sub-Saharan Africa in the presence of structural break. It uses data on the average official exchange rate of currencies of the selected countries to the US dollar from November 1995 to October 2015. This study employs Perron unit root test with structural break to endogenously determine the break period in the forex markets. It also employs the Kim wild bootstrap variance ratio test and BDS independence test to detect linear and nonlinear dependence in forex market returns respectively. In the full sample period, the Kim wild bootstrap joint variance ratio test shows that only two forex markets are efficient while the BDS independence test reports that all the forex markets are not efficient. The subsample period analysis indicates that the efficiency of the majority of the forex markets is sensitive to structural break, thus providing evidence in support of the adaptive market hypothesis. This study suggests that ignoring structural break and nonlinearity of returns may lead to misleading results when testing for market efficiency

Does Capital Structure impact on the Performance of South African listed Firms?

Issues surrounding capital structure and performance have been widely debated in literature, yetthere has been no conclusion as to how composition of firm’s capital impact on it performance.Using data on 136 quoted companies on the JSE from January 2000 to December 2014, and with aGMM analysis we explore the impact of capital structure on firm performance metrics in SouthAfrican. The study suggests that total debt to total equity and total debt to total assets are inverselyrelated to both Tobin q and return on assets, while long-term debt to total assets was relatedpositively to both Tobin q and return on assets. On the other hand, total debt to total equity andlong-term debt to total assets were inversely related to return on equity, while total debt to totalassets were positively related to return on equity. It is therefore recommended that firms need todefine their financial objective – either to maximise ROA or ROE. However, an optimal debt/equitymix must be sought, if both financial objectives must be pursued

Asymmetric Information and Volatility of Stock Returns in Nigeria

This paper investigates the effect of asymmetric information on volatility of stock returns in Nigeria using the best-fit Asymmetric Power Autoregressive Conditional Heteroskedasticity, APARCH (1,1) model, under the Generalized Error Distribution (GED) at 1% significance level from 3 January 2000 to 29 November 2016. The descriptive statistical results showed that the returns were not normally and linearly distributed, with strong evidence of a heteroskedasticity effect. The results of the analysis also confirmed the effect of asymmetric information on the volatility of stock returns in the Nigerian stock market. The asymmetric parameter (γ) was negative at (-1.00), which is statistically significant at 1% level. This confirms that there is an asymmetric or leverage effect where bad news had a more destabilizing effect on the volatility of stock returns than good news. The total impact of bad news on volatility was explosive at 2.0, during the period under review. Also, the volatility persistence which is measured by the sum of ARCH(α) and GARCH(β) stood at 1.695950. This is above unity and suggests that volatility takes a long time to attenuate in Nigeria. This could be largely ascribed to the persistent effect of the 2008 global financial crisis, which probably eroded investors’ confidence in the market