117 research outputs found
CHARACTERIZATION OF BARLEY (Hordeum vulgare L.) WITH ALTERED CARBOHYDRATE COMPOSITION
The concentrations of storage constituents in barley (Hordeum vulgare L.) grain impact its use for malt, food, feed, and fuel. Characterization of major grain constituents such as carbohydrates (total dietary fiber, beta-glucan, starch and its components amylose and amylopectin, starch granule size and physical properties), protein and fat and their interaction during starch enzymatic hydrolysis will facilitate diversification of barley grain utilization for improved malt, food or feed applications. Improved understanding of genes and their structure associated with beneficial grain constituents will help in barley improvement program to develop novel cultivars with desirable grain constituents. Nine barley genotypes with varying amount of amylose in grain starch were used to: (i) determine grain carbohydrate (dietary fiber, beta-glucan and starch), protein and fat concentrations, and starch composition and structure on its enzymatic hydrolysis; (ii) characterize allelic variation in granule bound starch synthase 1 (Gbss1) and starch branching enzyme 2b (Sbe2b) to understand the molecular basis for variation in grain starch amylose concentration. Nine barley genotypes included, one normal (~25% amylose), three near waxy ( 38%) starch. Total starch concentration showed significant positive correlation with thousand grain weight (TGW) and negative correlation with amylose, total dietary fiber and protein concentrations. Starch granule sizes varied with percent amylose where the increased amylose genotypes produced significantly lower volume percentage of C-type granules ( normal > increased amylose. Rapidly digestible starch (RDS) increased with a decrease in amylose concentration. Atomic force microscopy (AFM) analysis revealed higher polydispersity index of amylose in CDC McGwire and increased amylose genotypes which could contribute to their reduced enzymatic hydrolysis, compared to waxy starch genotypes. Increased β-glucan and dietary fiber concentration also reduced enzymatic hydrolysis of meal samples. Average linkage cluster analysis dendrogram revealed that variation in amylose concentration significantly (p < 0.01) influenced resistant starch concentration in meal and pure starch samples. RS is also associated with B-type granules (5-15 µm) and amylopectin FIII (19-36 DP) fraction. Gbss1 nucleotide sequences revealed considerable heterogeneity, with three genotypes with severely reduced GBSSI proteins and low amylose concentration had a 403 bp deletion in the promoter region. One previously described amino acid substitution D287V in CDC Alamo was confirmed and two new amino acid substitutions, G513W in CDC Fibar and Q312H in near waxy genotype SB94912 were identified as the likely causes of inactive GBSSI resulting in no amylose in starch granules. In the increased amylose genotype SB94983 A250T substitution was also observed, which can alter GBSS 1 enzyme specificity and could be a possible reason for increased amylose concentration. To facilitate studies of GbssI expression, positive assays for four allele variants were developed in this study. These markers may also be useful for monitoring introgression of respective GbssI alleles in barley improvement programs. The barley Sbe2b gene sequence analysis of the normal (CDC McGwire), near waxy (SB94912) and increased amylose (SH99250) genotypes, revealed 22 exons and 21 introns. The three Sbe2b alleles showed 21 polymorphic sites, present only in the introns, predicting that the processed SBE IIb transcripts to be identical in the three genotypes. The longest second intron of Sbe2b, which is known to regulate promoter activity in barley was identical between SH99250 and CDC McGwire, but SB94912 allele differed at 12 sites. The remaining nine polymorphic sites were present in introns 17, 18, 19 and 21. It is speculated that allelic variation in Sbe 2b second intron could be a reason for increased amylose concentration in SB94912. In summary reduction in amylose concentration can be due to changes in GBSS1 polypeptide, but the reasons for increased amylose starch are not yet clear. The DNA polymorphisms identified in this study can be used in a marker assisted selection strategy to follow the introgression of respective alleles in a barley improvement program
Explaining Individuals’ Behavior towards Their Acquisition of Students’ Loan in the US
This study investigates the behavior of individuals in the US regarding the amount of student loans they might borrow with a two-part model. The model was estimated using the 2013 Survey of Consumer Finance (SCF) data, collected by the Governors of the Federal Reserve System, US, in collaboration with the Statistics and Income Division of the Internal Revenue Service, US. The sampling and imputation errors that are associated with the SCF data were accounted for in the model estimation process to ensure reliable inferences. Old age (41 years and older), previous experience with bankruptcy, attitude towards borrowing to finance education, being Hispanic, employment status, and wage salary were found to be significant variables that can influence the likelihood that a student will borrow a student loan and the amount he/she would borrow. This study also found out that using the SCF data without accounting for the inherent imputation and sampling errors, could lead to biased estimates and incorrect model inferences. The results of this study could help students’ loan managers and other relevant stakeholders such as the Federal Government understand the behavior of potential borrowers of student loans to effectively manage the program
FDI, INFLATION, EXCHANGE RATE AND GROWTH IN GHANA: EVIDENCE FROM CAUSALITY AND COINTEGRATED ANALYSIS
This study used co-integrated analysis and Granger causality test in modelling the Growth Domestics Products (GDP) of Ghana with other three selected macroeconomic such as Foreign Direct Investment (FDI), inflation and real exchange rate for the period of 1980 to 2013. Data were taken from the World Bank’s World Development Indicators and Bank of Ghana. The objectives of the study are to examine both long-run relationships and direction of causality between the GDP and the macroeconomic variables. The time series properties of the data were, first, analysed using the Augmented Dickey-Fuller (ADF) test and KPSS test. The empirical results derived indicate that all the variables were stationary after their first differencing; i.e. variables are integrated of order one. The study further established that there is co-integration between the selected macroeconomic variables and GDP in Ghana indicating long run relationship. The above long term relation indicates that exchange rate and foreign direct investments have a negative effect on GDP whiles Inflation (CPI) showed a positive effect on GDP. The study further investigated the causal relationship using the Granger Causality analysis, which indicates a unidirectional causality between GDP growth rate and exchange rate and bidirectional causality between Inflation rate and Exchange, and also between Inflation rate and GDP, whiles FDI does not granger cause Inflation rate, exchange rate, GDP and visa versa in Ghana for the study period at 5%
Customer Relationship Management Practices and Customer Retention at Ghana Commercial Bank (GCB) in Tamale: Mediating Role of Customer Satisfaction
With the recent increase in bank closures, attracting new customers and developing strong customer relationships in Ghana's financial sector has become difficult. As a result, customer retention in banking has become critical for fund mobilization and license maintenance. The study sought to investigate the effect of CRM practices and customer satisfaction on customer retention at GCB bank, Tamale. The quantitative research approach and the explanatory design were employed due to the purpose of the study. Structured questionnaire was used to gather data from all the 367 customers of GCB bank in Tamale. The data obtained were processed using Statistical Package for Social Sciences (SPSS) version 25 and analyzed using descriptive and inferential tools. The purpose of this study was to investigate and establish a comprehensive framework to identify customer relationship management practices on customer retention through the mediating role of customer satisfaction. The study discovered a significant positive relationship between customer relationship management practices and customer retention, as well as customer satisfaction playing a mediating role in this relationship. As a result, Ghanaian banks are implored to implement effective customer relationship marketing strategies in order to retain their customers. Keywords:Customer Relationship Management (CRM) Practices, Customer Retention, Customer Focus, Knowledge Management, Technology-based CRM, Customer Satisfaction. DOI: 10.7176/JMCR/85-02 Publication date: February 28th 202
Explaining the Saving Behavior of Households’ in Ethiopia, Africa
Savings have been shown to have a positive impact on economic growth at the macroeconomic level. But, the micro-level analysis of households’ savings behavior is limited, especially in Sub-Saharan African economies. This study contributes to the understanding of the savings behavior of households in Africa, by modeling the savings behavior of households’ in Ethiopia with the two-part model. The results of the study reveal that number of extension contacts and access to market information have significant positive effects on the likelihood that a household would save. Moreover, land holdings (bad production season last year) have significant positive (adverse) impact on the expected amount of money a household would save. Based on the results of this study, policies are recommended to increase savings in Ethiopia
Influence of nutrient sources and environmental conditions on vegetative growth of fungus, Erythricium salmonicolor (Berk. & Broome) Burdsall in cocoa
Erythricium salmonicolor is the cause of pink disease in cocoa in the humid tropics. The growth of 4 isolates (ES-WR006, ES-WR008, ES-ER009 and ES-ER010) of the fungus on different sources of nutrient (carbohydrate, amino acid and vitamin) and environmental conditions (temperature, pH and light) were evaluated in the laboratory. The pink disease isolates utilised the nutrients to different extent, with the best radial mycelial growth rate achieved with isolate ES-WR008 followed by ES-WR006. None of the isolates produced spores in the laboratory. The isolates utilised polysaccharides as best as disaccharides and monosaccharaides. Among 7 amino acids assayed, aspartic acid was the most promising for vegetative growth. The best radial mycelial growth on vitamins was attained on folic acid and riboflavin. The minimum, optimum and maximum temperatures for growing the fungus were 18 °C, 28 °C and 34 °C respectively. Survival of E. salmonicolor isolates within the temperature range of 18-34 °C is consistent with temperatures for growing cocoa in Ghana. The isolates also grew well within a pH range of 4-8, with the best growth at pH 6. Light quality and duration influenced the vegetative growth of the isolates. Pink disease isolates maintained in 24 hr darkness or 24 hr light performed better than in alternating 12 hr darkness and 12 hr light. There was a significant (p<0.05) repressive effect of the alternating dark and light exposures on vegetative growth of the fungus. The implications of the results for efficient management of the cocoa disease are discussed
Teaching Interactive Art Lessons with Recycled Waste Materials as Instructional Resources
The study examines the use of waste materials as instructional resources in teaching and learning Art lessons. Primary, Junior and Senior High School Art teachers in Ghana mostly teach their lessons without instructional resources because the government is not able to provide materials to create the needed resources. The study therefore explored local waste materials which create nuisance in the environment in Ghana to create appropriate teaching resources for Art in Ghana. This study shows differences in classroom atmosphere and student performance when instructional resources are used or not used in teaching and learning. The study adopted the exploratory, quasi-experimental and descriptive research methods. Art teachers from Kumasi were selected to teach with developed instructional resources after which lessons taught with and without the instructional resources were compared. The study found that when instructional resources are used for teaching and learning, lessons become more practical, interactive, interesting and real to pupils and students, and enables them to perform better in their academics. Keywords: Instructional Resources; Waste Materials; Recycling; Teaching and Learning
The Theoretical and Socio –Cultural Dimensions of Kpando Women’s Pottery
Pottery plays a very important role in the indigenous culture of the various ethnic groups in Ghana. At Kpando in the Volta Region, the art of pottery making, the meaning and uses of the artefacts are enshrined in some deep philosophies that permeate the socio-cultural life of the people. However, the rich theoretical and cultural components of the art have not been fully documented, and are not well understood and appreciated. This knowledge gap has rendered this cultural landmark almost invisible in cultural anthropology and native art. This study therefore provides an intellectual review of indigenous pottery production at Kpando with the view to unearth their role in the social sustainability of the indigenous people. The paper takes a critical look at the ontology of the art, clay winning process, pottery production, their usage and associated taboos. The descriptive method of qualitative research was employed for the study. The findings of the study show that traditional pottery production in Kpando is principally women’s art and the artefacts have both theoretical and cultural undertones. Keywords: Pottery production, native art, theoretical undertone, Kpando wome
Advances on the pyroresistive behaviour of conductive polymer composite
PhDThe positive temperature coefficient (PTC) effect in conductive polymer composites (CPC) are still poorly understood with the thermal expansion of the polymer matrix accepted as the main cause. This thesis aims to study a model system able to explain the effect of the filler size and shape on the PTC behaviour of CPCs. Silver coated glass spheres and flakes are used as conductive fillers due to the ease in controlling uniform size and shape. In a controlled system it was demonstrated that the PTC intensity increases with increasing filler size and with decreasing filler content, both for conductive fillers.
Combinations of different conductive fillers were investigated to explore the possibility to obtain both low percolation thresholds and high PTC intensities. Model systems in which at least one of the two conductive fillers is of relatively homogenous size and shape were used to facilitate unravelling some of the complicated relationships between (mixed) conductive fillers and the PTC effect. The PTC intensity of mixed fillers composites were dominated by the filler with the lowest PTC intensity, even at very low volume fractions. The PTC intensity was not only influenced by the conductive particle size but also by its size distribution.
The effect of difference in linear coefficient of thermal expansion (CTE) of conductive fillers and polymer matrix based on a change in filler core on PTC behaviour was investigated. Damage to the particles due to the poor adhesion between the silver coating and the PMMA bead lead to the composite behaving like mixed filler composite.
Hybrid polymers filled with silver coated glass flakes was also examined in order to enhance the PTC intensity. The PTC intensity of the composite increased with increasing PPE content but the negative temperature coefficient (NTC) effect was observed in all the composites
Evaluation of incorporating plastic wastes into asphalt materials for road construction in Ghana
In improving the aesthetics of the environment, the management of plastic wastes cannot be left out of the picture. Among the numerous ways that plastic wastes are managed, incorporating them into plastic roads is another viable option. This study quantified plastic wastes generation in Sunyani Municipality in Ghana and investigated the optimum percentage of asphaltic materials that could be made of plastic wastes for road construction in Ghana. Plastic Wastes were obtained from social gatherings, residential areas and restaurants, there was dialogue with key persons in the plastic industry and various experiments were also conducted for plastic wastes utilization in road construction. It was found that only one entrepreneur recycles the plastic wastes to make bags, dustbins, ropes and many more in the Municipality. It was also estimated that plastic wastes generation in the municipality per capita was 49.7 g/person/day whiles the total plastic wastes generated in the Municipality was 6,725.64 kg/day. In addition, numerous experimentations proved that it is possible to substitute about 10% of asphaltic road materials with plastic wastes as plastic coated aggregates (PCA) to meet the Ghana Highways Authority (GHA) standards for road construction. The novelty finding in this research is that substitution of about 10% or more of asphaltic road materials in Ghana with plastic wastes could bring economy and cost savings in both road construction and plastic wastes management in Ghana
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