215 research outputs found

    Morphological, molecular genetic and host plant relationship studies of rice and weed infesting populations of brown planthopper, Nilaparvata lugens (STAL) (Homoptera: Delphacidae)

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    A total of fifteen experiments including morphological, molecular genetic and host plant relationship studies were conducted to differentiate between two sympatric populations of brown planthopper (BPH), Nilaparvata lugens, one from rice (Oryza sativa) and the other from Leersia hexandra, a weed grass. The scatter plot based on seven morphometric characters indicated that N. bakeri was totally an isolated species. Insects with high esterase activities (usually caught off rice) and those with low esterase activities (usually caught off L. hexandra) showed 6-8% overlapping between the two populations of N. lugens. But scatter plot of the morphological characters of stridulatory organs produced distributions that were almost nonoverlapping indicating that BPH with high esterase activity usually caught off rice is different from BPH with low esterase activity usually captured from L. hexandra. Scanning electron micrographs showed some variations in different morphological characters between individuals from the two sympatric populations of BPH but these were not population specific. No heterogametic mating occurred in mate choice experiments. Crosses between the two BPH populations from different host-plants showed some barriers for hybrid production. Some genetic incompatibility may exist between the two populations. After being tested for esterase activity, samples were analysed for six loci found to be polymorphic at 95% criterion namely, Mdh, Idh, Pgm, Gpi, 6Pgd and A cp . The genetic distance (average 0.182) and the existence of a diagnostic enzyme marker (GPI) between rice and Leersia infesting populations indicated that both populations are closely related but different species. The inheritance of GPI, IDH and MDH isozymes were studied in families generated from mating individuals of two sympatric populations of N lugens. These isozymes were controlled by three loci, Gpi, Mdh and Idh, respectively. These loci were inherited in simple Mendelian fashions. Thirty one bands from both short and long primer RAPD were able to be tested for segregating ratios in two families of N lugens and they were found to be inherited in simple Mendelian fashions. In the population genetic studies, two diagnostic bands, one from short primer RAPO (OP003.7; 0.6Skb) and the other from long primer RAPD (pehA#6.3; 1.00kb) were found to be present only in the Leersia infesting populations of BPH. The DPGMA cluster analyses based on both enzyme and RAPD markers showed that all the rice infesting populations of N. lugens clustered together as a group. On the other hand Leersia infesting populations of the same localities formed another distinct cluster. In host plant relationship studies, rice plants were found best suited for the establishment of the rice infesting population, and L. hexandra was a favourable host for the Leersia infesting population A consideration of the evidence from studies on host plant relationships, reproductive isolation, hybridization, morphometric variations, level of esterase activity, existence of diagnostic isozyme and DNA level markers, genetic distance, consensus tree and molecular variance between N. lugens with high esterase activity usually caught off rice and N. lugens with low esterase activity usually caught off L. hexandra suggested that both insect populations from Malaysia belong to closely related sibling species. This information has practical implications in formulating effective control measures against N. lugens which is a major pest of rice not only in Malaysia but also throughout South East Asia, South Asia and Australi

    Dynamics of Remittance in Bangladesh: A Case Study on United Commercial Bank (UCB)

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    The aim of this paper is to evaluate the inward as well as outward remittance performance of United Commercial Bank (UCB), Bangladesh. The study exposes that the inward and outward remittance of UCB has been increasing over the years i.e. from 2007 to 2013. In 2013, the highest inward remittances come through Xpress money among the leading five products (Xpress money, Western Union, NEC Italy, Money gram and Modern Exchange). In 2013, the remittance inflow has decreased compared to 2012 from Soudi Arabia, Libya and United States of America while remittance in flow has increased from Malaysia, United Kingdom, Italy, Kuwait and Qatar. The rate of growth of inward remittance of UCB has dropped after 2010, although in 2013, it increased a little bit compared to 2011 and 2012. While growth rate of outward remittance showed an erratic trend form 2010 to 2013. Based on the findings it can be said that UCB should introduce new inward remittance product as well as it should arrange seminar and symposium to introduce the cost and benefits of their remittance products in home and abroad which may increase the remittance flow from different countries and  this will ultimately benefit the county’s economy. Keywords: UCB, Inward remittance, Outward remittance, Growth rate, Erratic trend, and Cost and benefit

    focusing on Korean case

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    Thesis(Doctoral) --KDI School:Ph.D in Development Policy,2019The objective of this thesis is to empirically investigate the determinants of the returns to holding Real Estate Investment Trust (REIT) and Real Estate Investment Fund (REF) by using firm-level panel data covering 129 REIT and REF from Korea for the period of 2001 through 2018. Through the panel regression analyses, the following results are obtained. It is shown that the company status as REIT or REF is not statistically significant factor for Return on Asset (ROA) and that there is no statistically significant difference between stock exchange listed REIT and REF and non-listed REIT and REF in return earnings. Nonetheless, the indicator of scale economy is shown to positively affect returns: one percent increase in asset raises ROA by 0.014 percent; and, the effect of the firm size is shown to be non-linear, i.e., increasing with decreasing rate indicating diminishing marginal returns that is consistent with the conventional microeconomic theory. The results also show that capital structure has a negative impact on the return: one percent increase in the liability to assets ratio decrease 0.314 percent in ROA. REIT is shown to be more responsive than REF in terms of the leverage effect on the return. Finally, it is shown that, ceteris paribus, highly levered firms are inflicted with a larger negative shock inflicted by that recent global financial crisis (GFC). Regarding policy implication of REIT and REF in Developing Bangladesh, solving supply side constraint of housing in populated Bangladesh, real estate investment through REIT and REF may be a good alternative and by legal and institutional framework setting the country may introduce these indirect investment vehicles in the country.Chapter 1- Introduction Chapter 2- Literature Review and Hypothesis Chapter 3- Research Methodology Chapter 4- Results and Discussions Chapter 5- Conclusions and RecommendationsdoctoralpublishedMd Abdul LATIF

    Job Satisfaction of Employees in Banking Sector: A Case Study on Janata Bank Limited

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    The aim of this study is to evaluate the level of job satisfaction of the employees of state owned commercial bank (SCB) named as Janata Bank Limited. Data was collected for this study by questionnaire method. The study shows that Job preference, Cooperation among Co-workers, Working Environment, Working Facilities, Salary Satisfaction, Increment Satisfaction, Welfare Facilities, other facilities, Performance Appraisal System, Behavior of boss, Career Development organism, and Promotion system significantly influence job satisfaction of  employees. The study indicates a positive sign regarding overall job satisfaction of employees of the bank. In such situation, job satisfaction of bank officers becomes an important issue that has to be taken care of in order to achieve ultimate goals of the banking sector in Bangladesh. Keywords: Job satisfaction, SCB (state owned commercial bank), Bank Employees and Satisfaction Leve

    A state approach to the management of concurrent design task design of symmetrical woble plate compressor

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    This paper discusses how state space control concepts may be applied to the modelling and control of coupled, concurrent design tasks subjected to unexpected, dynamic disturbances. The Homogeneous State Space (HSS) model determines the natural response shape of the design process and predicts the number of iterations before all the design tasks are completed, while the Non-Homogeneous State-Space (NHSS) model precisely monitors and controls the stability and the convergence rate of each design task. The amount of additional work or resources required by each task at every stage of iteration can be determined; this facilitates workload distribution and resource allocation in design task planning and scheduling. A case study of the design of a new symmetrical wobble plate compressor is discussed to validate the proposed models in monitoring and controlling the stability of design tasks under the influence of unexpected disturbance

    Psychometric properties of teacher classroom assessment literacy instrument using Rasch model analysis

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    A teacher classroom assessment literacy (TeCAL) instrument was developed to measure the level of teacher classroom assessment literacy in schools. TeCAL contains 66 multiple choice items with four options based on four constructs namely purpose, measurement, evaluation and use. Thus, this study aims to identify the psychometric properties of TeCAL using Rasch measurement model (RMM) analysis through Winstep software version 3.72.3. The findings show that the compatibility values of mean square (MNSQ) infit and outfit items ranged from 0.64 to 1.46 and 0.40 to 2.23, respectively. The value of MNSQ outfit was outside the set range, but still met the other fit statistics indicator which has a positive point measure correlation (PTMEA) value. In addition, the findings show that the empirical raw variance explained by measures is 38.2%. It was very close to the modeled value of 38.4% with the empirical unexplained variance in 1st contrast being 7.5% less than the maximum controlled 15%. Largest standardized residual correlations identified 10 pairs of dependent items to be less than 0.7. The person and item reliability index values were 0.94 and 0.89 with separation index values of 2.90 and 3.80, respectively. Overall, this psychometric analysis is crucial to ensure that the TeCAL instrument has good quality and meaningful to use
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