Using a surface energy budget framework to characterize grass-biophysical response to changes in climate in support of on-farm decision making in Ireland

xxiv Abstract This thesis, for the first time in Ireland, uses a framework that combines a land surface scheme (LSS) based on a surface energy budget theory, available environmental observations, land surface and atmospheric analyses, to understand essential mechanistic factors that determine grass growth response across the Irish landscape. A soil moisture model parameter (C soil) is identified as the key factor that distinguishes soil types and their ability to retain water for plant growth, plant response to exchange processes, and drives the response of LSS in drying soils. A Modification of this parameter indicates that the LSS can be transferred to other locations. In the context of understanding the links between land surface dynamic processes and the persistence of 2018 summer drought regionally, drying soils and high atmospheric anomalies result in a reduced evapotranspiration (ET) process. This is the situation over grasslands in the east and south east of the country where a wet ‘evaporative’ regime quickly shifts into a ‘transitional’ regime in which vegetation functioning and ET are controlled by soil water availability. Particularly, a threshold value of soil moisture content that suggests the onset of 2018 agricultural drought has been found across the regions. The importance of water use efficiency for monitoring grass growth at field level and for distinguishing zones of optimum productivity is further discussed in the thesis. Overall, the findings demonstrate the potential consequences of climate change on Irish grasslands and the need for policies that are tailored to reinforcing observation networks to complement theories and model outputs akin to on-farm adaptation and optimization of water availability and productivity

Effectiveness of recombinant hepatitis B vaccine with/without the passive hepatitis B immunoglobulin vaccine in babies whose mothers are hepatitis B surface antigen positive in a private missionary hospital

Background: Hepatitis B infection is a potentially life-threatening liver infection. The burden is more in the less developed countries. Vaccination is the most cost-effective way to control hepatitis B virus (HBV) infection and its chronic complications globally. Active-passive immunoprophylaxis using hepatitis B immunoglobulin combined with recombinant hepatitis B vaccine is recommended for infants of women with chronic HBV infection. This study aimed to determine the effectiveness of the hepatitis B recombinant vaccine alone or combined with hepatitis B immunoglobulin.Methods: The study was a prospective longitudinal study. Patients were selected using a convenient sampling technique. The study spanned between 1 January 2017 and 31 December 2018. Data analysis was with SPSS version 21.Results: The unit recorded 1690 deliveries during the recruitment period, 70 eligible patients were recruited thus giving an incidence of 4.1%. 74.3% of the recruited patients were HBeAg negative while 25.7% were HBeAg positive. 52.9% of the babies had only recombinant HB recombinant vaccine while 47.1% had combined hepatitis B immunoglobulin and the recombinant vaccine at birth. The HBeAg status of mothers played a significant factor in the HBsAg positivity of babies two months after the completion of immunoprophylaxis against HBV.Conclusions: Giving recombinant HBV vaccine in combination with the HBV immunoglobulin is the standard practice, this may not always be so based on the findings from this study. However, the population studied is too small to make a categorical statement thus a larger population needs to be studied.

Development and testing of a Prosopis africana pod thresher

Prosopis africana is an under utilized tree crop with immense medicinal and industrial values. Manual threshing of the pods to extract the seeds is uneconomical, time consuming, associated with drudgery and low output capacity. A motorized Prosopis africana pod thresher was designed, fabricated and assessed for performance. The main components of the thresher include hopper, threshing unit, cleaning fan and the frame. The best threshing performance index of 92.55 % which comprises of 98.03 % threshing efficiency, 94.45 % cleaning efficiency, 2.36 % seed loss and 1.59 % mechanical damage index was obtained. A combination of 1200 rpm cylinder speed, 1200 rpm fan speed, 30 kg/h feed rate and 16 % wb moisture content of the pods is recommended for optimum results. The thresher has a capacity of 70 kg/h. The performance of this thresher has indicated the possibility of exploiting the full industrial potential of Prosopis africana pods and seeds

Performance and economic comparisons of manual and mechanised fertiliser applications for mature oil palm

The problem of labour shortage in addition to environmental hazard due to improper fertiliser application method calls for efficient and effective method of fertiliser application. This study compares the productivity of workers, human energy expenditure and operational cost between manual and mechanised method of fertiliser application operation for matured oil palm in Malaysia. Results indicate that workers' productivity increased by 3.74 times with mechanised method compared to the manual method based on the measured field capacities of 4.64 ha per hour and 1.24 ha per hour for the mechanised and manual methods, respectively. In addition, mechanised fertiliser application was 4.53 times less labour intensive than manual application based on the measured human energy expenditure of 2.03 kcal per min and 9.19 kcal per min for mechanised and manual methods, respectively However, the estimated total cost for the mechanised method is 1.6 times more than the manual method which amounted to an additional cost of RM4.18 per hectare based on the estimated total cost of RM11.10 per hectare and RM6.92 per hectare for mechanised and manual methods, respectively. The high estimated total cost of the mechanised method is due to the low annual usage of the tractor considered in the economic analysis for this study

Audit Reporting Lag and Firm Value in Nigerian Food and Beverage Companies

Delays in financial reporting give a negative signal to the market and adversely affect the company’s market value. Financial reporting lags raise suspicions among market participants regarding concealment of any potential bad news by a firm, which may affect its share value. Thus, the study investigates the interaction of audit reporting lag and firm value in Nigerian beverage and food companies. Audit delays lead to the late publication of financial statements, enhancing the information asymmetry problem, and affecting firm value. We obtained the data from annual reports of 10 listed companies for five years. The Generalized Method of Moments (GMM) estimation is used to analyze the data. The results suggest that audit delays do not affect the market value of a firm. Previous studies mainly focus on the relationship between corporate governance firm characteristics, and audit reporting lag in Nigeria. To the best of our knowledge, the impact of audit delays on firm value in Nigeria is yet to be adequately explored. The finding may help statutory bodies in reducing the period of financial reporting. The results may also help firms improve their performance and promote an environment that may give investors confidence. This study has focused on the food and beverage sector in Nigeria. Future studies can be undertaken in other sectors which may bring more insight to the issues related to financial reporting lags

Serum total Calcium to Magnesium ratio is higher in Sickle cell disease patients with proteinuria than without proteinuria

 Intracellular imbalance in the levels of calcium to magnesium ratio could lead to clinical complications in Sickle cell disease patients (SCD). Proteinuria is common in SCD patients especially with increasing age and may affect the intracellular level of calcium to magnesium ratio. This study evaluates the total calcium to magnesium ratio in SCD patients with proteinuria and compared to those without proteinuria. Serum total calcium and magnesium were determined using colorimetric method, while urine protein was assayed using urinalysis dipstick and sulphosalicylic turbidometric method. Out of the 100 SCD patients, urine protein was detected and assayed in 27 while 73 were negative for urinary protein. Total calcium to magnesium ratio and urine protein were significantly higher (p<0.001), while magnesium (p<0.001) and calcium (p<0.01) were significantly lower in SCD patients with proteinuria compared to those without proteinuria. Total calcium to magnesium ratio correlated positively (r=0.38;p<0.05) with proteinuria in SCD patients. Total calcium to magnesium ratio is higher in SCD patients with proteinuria than without proteinuria. Routine calculation of this ratio could be helpful in assessing the intracellular balance of calcium and magnesium in the management of SCD patients

Calibration and accuracy determination of a microwave type sensor for measuring grain flow

Impact type grain flow sensor for crop yield monitoring is known to have problem of some thrown grain by the elevator conveyor in a combine not hitting the sensing impact plate. New technology of microwave solid flow sensor was used to solve the problem of impact-type sensor. A calibration stand with its instrumentation systems to stimulate the actual operation of the clean grain auger in a rice combine had been designed and constructed in this study for the purpose of conducting the calibration and evaluation study of the sensor. Two different solid flow sensor orientations and three different solid flow sensor extrusions were investigated in order to find the best positioning of the sensor on the chute for the measurement. Results from the conducted tests indicates that the best sensor positioning is on totally flat ground at 180o orientation and 8 cm extrusion of the chute cross section (R2=0.9400). Then, the solid flow sensor was tested at seven chute pitch angle positions (i.e-4.5o, -3.0o, -1.5o, 0o, +1.5o, + 3.0o, and +4.5 o), seven chute roll angle positions (i.e-4.5o,-3.0o, -1.5 o, 0o, +1.5o, +3.0 o, and +4.5o). Finally, accuracy tests undertaken to compare the real time measurements against the average flow measurements. ANOVA test shows that both pitch angle and roll angle positions have significant effects on the measurement accuracy of the sensor. The measurement errors increased with increasing roll angles and increasing pitch angle. Conclusively, this conducted laboratory study was able to quantify the measurement accuracy of the SWR Solid Flow sensor for real-time measurement of grain flow under a simulated laboratory rice combine test set-up

Physical and mechanical properties of Jathropa curcas L. fruits from different planting densities

Jatropha curcas L. is a versatile and rugged crop with enormous unexploited potentials. In order to efficiently take advantage of its full potentials, its physical and mechanical properties need to be well understood. Laboratory tests were conducted to investigate the properties of Jatropha curcas L. fruits obtained from trees of three planting densities namely 10880, 5446 and 3630 plants acre-1. The properties included detachment force, rupture force, deformation at rupture point, deformation ratio at rupture point, hardness, energy used for rupture at both vertical and horizontal loading positions. Other properties studied were 1000 unit mass, dimensions, sphericity, bulk density, solid density, porosity, coefficient of static friction on plywood, steel and stainless steel. The solid density value of 0.97 g cm-3 was obtained which implies that the fruit could float in water for easy cleaning and separation from foreign materials. It was observed that the fruit had the least coefficient of static friction on stainless steel (0.44). The average values obtained for the detachment force and rupture force at vertical orientation were 16.62 N and 57.17 N, respectively. No clear cut trend was observed in the physical and mechanical properties with respect to planting density. However, the mechanical properties were significantly different with respect to the orientation of the fruits. Both the physical and mechanical properties are essential for the design and development of harvesting and processing machines for Jatropha curcas L. fruit

Effects of operational variables on rotary valve metering system for a variable rate technology fertilizer applicator for oil palm

In the Malaysian oil palm plantation, fertilizer application was observed to be done manually or mechanically at uniform rate without due consideration to nutrient variability. The available constant rate mechanical fertilizer spreaders on oil palm plantation were found to be susceptible to excessive fertilizer application. On the other hand, Variable Rate Technology (VRT) could be used to forestall the hazards of excessive fertilizer application. However, full knowledge of the operational variables of the metering system of a VRT applicator has become inevitable for proper utilization of this technology. A rotary valve metering system test rig was designed and constructed for the purpose of studying the characteristics of the system. A linear regression equation was developed to relate the discharge rate of the metering system to the screw conveyor speed, rotary valve speed, fertilizer bulk density and repose angle. The coefficient of determination (R2) of the regression equation was 98.65%. The screw conveyor speed, the rotary valve speed and type of fertilizer were found to have statistically significant effect on the discharge rate of the system. It was observed that the discharge rate of the system decreased with increase in rotary valve speed. The outcome of this study will enhance the use of rotary valve in the VRT fertilizer applicator for oil palm

Effect of adding palm oil mill decanter cake slurry with regular turning operation on the composting process and quality of compost from oil palm empty fruit bunches

Formation of compost from oil palm empty fruit bunches (EFB) and decanter cake slurry by adding palm oil mill effluent (POME) with regular turning operation was investigated. The experiment was conducted in a commercial composting plant under the normal production process. The addition of decanter cake slurry has hastened the composting process of the EFB. The C/N ratio after 51 days for the mature compost with the decanter cake slurry was 18.65 while that of the matured compost without the decanter cake slurry remained high at 28.96. The compost formed from the addition of decanter cake to EFB and POME had 46.4% nitrogen, 17.9% phosphorus, 17.7% potassium and 23.1% calcium more than that without decanter cake. The use of compost produced from EFB, POME and decanter cake slurry could solve more environmental problems and enhance economic benefits in the oil palm industry