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The west African honeybee, Apis mellifera adansonii, is a subspecies of western honeybees that live in a wide range of habitats. In Nigeria, there is a lack of knowledge of its population genetics. Thus, we examined its mitochondrial genetic diversity and population structure using the subunit I of the cytochrome c oxidase gene. Our results showed an overall high level of genetic diversity (haplotype diversity = 0.702) of A. m. adansonii in Nigeria. Analyses revealed a low level of population genetic structuring (ΦST = 0.31986) across the geographical regions of Nigeria. Results showed that a substantial degree of haplotype diversity was evident in the populations from the Middle belt of Nigeria. However, individuals from southern Nigeria expressed low haplotype diversity. The mismatch distribution and historical demographics supported evidence of population expansion of A. m. adansonii in Nigeria. The matrilineal genealogy demonstrated a lack of clear patterns of population structuring. In sum, our analysis showed a high degree of genetic diversity with no population divergence within A. m. adansonii from Nigeria. Further study involving additional mitochondrial and nuclear gene markers could aid to elucidate gene flow patterns among populations of A. m. adansonii across its range in West Africa.

E-Tendering systems allow for electronic submissions of tender documents with communications support. There is a growing global acceptance of E-Tendering systems particularly in recognition of its ability to help reduce cost, reduce wastes, and modernise tendering processes. For global acceptance of E-Tendering, the system must satisfy the needs of its users especially in areas such as system performance. Amongst others, performance features will increase user satisfaction the better they are implemented. The aim of this paper is to report on an evaluation of the performance features of E-Tendering systems from a user-group’s perspective. A list of design features of E-Tendering systems is compiled from existing E-Tendering systems and the literature. A Kano model-based methodology is adopted, and data collected from Kano-questionnaire survey is used to evaluate the compiled set of E-Tendering system’s features. A Kano analysis of the survey results revealed that the participants perceived as performance features a significant percentage of the E-Tendering system’s design features presented to them. It was also established that some of the features are not perceived to contribute to user satisfaction. The performance features of E-Tendering systems which are perceived to mostly impact user satisfaction were presented and areas of future work highlighted.

Neem (Azadirachta indica A.) tree has been known to be useful in soil enrichment and for insect, pest and disease control. Thus, it is of benefit to study the allelopathic efficacy of powdered neem seed cake on the germination and seedling growth vigour of cowpea, groundnut, sesame, soya beans and Bambara groundnut. A field research work was conducted at college of Agriculture, Hassan Usman Katsina Polytechnic during the 2008 raining season using split plot design with three replication and six main plot treatment 0, 0.5, 1, 2, 4, and 8 tons/ha and the tested seeds as main subplot treatments. The result showed that powdered neem seed cake was found to have no allelopathic effect on the germination of cowpea, sesame, Bambara ground nut, ground nut at 0-2 tons/ha and soya beans at 0-4 tons/ha and have no allelopathic effect on the seedling growth vigour of cowpea, sesame, soya beans, Bambara ground nut and ground nut at 0-4 tons/ha. Further research is required on the allelopathic effect of powdered neem seed cake on the germination, growth and yield of these tested crops.

In this study, the structure of efficient recessed gate Metal Insulator Semiconductor High Electron Mobility Transistor with Quaternary Barrier materials of Al0.42ln0.03Ga0.55N was simulated and presented. The device with heterostructure of Al0.42ln0.03Ga0.55N/UID-AIN/GaN/GaN and thickness of 5 nm/10 nm/40 nm/10 μm on SiC substrate shows normally-OFF characteristics. The effect of high~k dielectrics of HfAlxOx and the quaternary barrier on the electrical performance of the device was analyzed and compared with the conventional AlGaN/GaN heterostructure. We found that the charge optimization concept of the polarization induced charges of the device 2DEG in the channel was due to the combination of the Quaternary Barrier of Al0.42ln0.03Ga0.55N and the high~k dielectrics of HfAlxOx. Furthermore, the two field plates used which are having a length of plate at the drain (LGFP) of 1.8 μm and field plate at the source (LGPS) 0.5 μm effectively spread the electric field lines with the drain and showed a significant improvement in the electrical properties of the device and achieved a maximum drain current of 710 mA/mmV, low transconductance (gm) of 0.158 Smm−1 and high breakdown voltage of 570 V. In comparison to the conventional AlGaN/GaN MIS-HEMTs of similar design, the result of this Quaternary Barrier Metal Insulator Semiconductor High Electron Mobility Transistor (QB-MIS-HEMTs) exhibited a better interface property, remarkable suppression of leakage current, and excellent breakdown voltage which are important for power switching applications.

Literature has revealed proliferation in the fabrication of new software metrics and their automated representations. The number of software metrics have been on high increase with relatively unmonitored standardization in formalized definitions and documentation of software metrics. This has produced inconsistent user-defined metrics on the different tools that implement software metrics. The consequent draw-back is inconsistent metrics result across different tools implementing the same metrics. This problem forms the foundation to irregular standard and/or universal definition and interpretation of metrics output. There is therefore need for the establishment and/or reinforcement of standards and technology that monitors and track metrics evolution towards achieving homogeneity in software metrics definitions and the tools that implement them. This paper is introducing a yet comprehensive implementation of new metrics model that unifies definition, interpretation, archiving, automation and consequently, extensibility. These rippling chained processes form the unified process model for implementing software metrics.

This paper examines the impact of export incentive schemes on the Performance of agricultural exports in Nigeria, using quarterly time series data from 1990-2014. The study employed Autoregressive Distributed Lag (ARDL) model to cointegration analysis and Granger causality test to examine the long run and causality relationship between growth in the Performance of agricultural exports and export incentive schemes in Nigeria. The bounds tests used in the study revealed that there is no long run equilibrium relationship between export incentive schemes and the performance of agricultural exports in Nigeria. It is of high importance to note that the granger casualty test indicates that there was a unidirectional relationship running from agricultural export (AGR) to export expansion grant (EEG), export development fund (EDF) to agricultural export (AGR). Since the findings of the study show that export development fund has positive and significant impact on the performance of agricultural exports in Nigeria, the study suggests that major concern should be given to its management and disbursement to ensure stable growth in the sub-component (agriculture) of non-oil export in Nigeria. This can be achieved through adequate funding by the concerned authority.Keywords. Export incentives, Non-oil exports, Causality, ARDL, Nigeria. JEL. J43, Q00, Q10.

In this paper, Al0.23Ga0.77N/GaN/Al0.05Ga0.95N Double Heterostructure-High Electron Mobility Transistor targeting a low loss and high power efficient boost converter circuit was simulated using a thin P+In0.2Ga0.8N cap under the gate. The charge balancing concept of the polarization induced field of the device was due to the Mg-doped P+In0.2Ga0.8N which shows normally-off characteristics. The high positive threshold voltage VT shift achieved with the device was correlated with the obtained dynamic RON of the device. This dynamic RON was characterized 19 μ s immediately after the device was turned-on and goes up to a maximum of 550 V. Furthermore, this Al0.23Ga0.77N/GaN/Al0.05Ga0.95N demonstrates low dynamic RON of ~6% with increment of efficiency of up to 40% when measured in the booster converter circuit. For power switching applications, the result of this P+In0.2Ga0.8N cap having a back-barrier/buffer of AlGaN achieved a dynamic RON performance with excellent breakdown Voltage VBR.OFF and much lower OFF-state gate/drain leakage as compared to the conventional GaN buffer structures.