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American University of Nigeria is a Nigerian university. Wikipedia.

Salatian A.,American University of Nigeria
International Journal of Smart Home

Building operators need to interpret the high volumes of noisy data generated from the environmental sensors in their buildings. In this paper we propose a software architecture which processes the building monitor data to provide enhanced decision support in the form of assessments and accurate summaries to building operators in order to improve the quality of building performance. Our architecture has been tested on over 8 days worth of continuous data and the results are very encouraging. Source

Pine H.J.,American University of Nigeria | Boyd C.E.,Auburn University
Journal of the World Aquaculture Society

A magnesium budget was prepared for a commercial low-salinity shrimp farm in the Blackland Prairie region of Alabama for one production cycle. Ponds had previously been used for production and fertilized with magnesium; two ponds (S-5 and S-6) for four previous years and one pond (N-9) for one previous season. Fertilization with sulfate of potash magnesia (K 2SO 4·2MgSO 4 or K-Mag ®) was applied to these ponds to obtain the concentrations of 20 mg/L, averaging 1274 kg Mg 2+/ha. Additional inputs of magnesium included groundwater, rainfall, and runoff averaged 441.5 kg/ha. A water budget for ponds indicated that 292.6 kg/ha of magnesium in outflows. The difference in inputs and magnesium outputs resulted mainly from adsorption of magnesium by pond bottom soils. However, the increase in exchangeable magnesium in the upper 15-cm layer of pond bottom soils was not great enough to account for the difference in total magnesium inputs and magnesium outputs in water and shrimp. Possible explanations for this discrepancy are magnesium precipitation, nonexchangeable fixation of magnesium by clay minerals, incomplete extraction of magnesium, and analytical error. The decreased uptake of magnesium by older ponds, S-5 and S-6, indicate that the soils had a diminishing affinity for the cation or an equilibrium concentration is being established. © by the World Aquaculture Society 2011. Source

Baker L.R.,American University of Nigeria | Tanimola A.A.,University of Port Harcourt | Olubode O.S.,University of Ibadan
American Journal of Primatology

The development of effective conservation and management actions for populations of wild species generally requires monitoring programs that provide reliable estimates of population size over time. Primate researchers have to date given more attention to evaluating techniques for monitoring primates in natural habitats compared to populations that occur in villages or urban areas. We conducted censuses to estimate the abundance and density of two sacred, village-dwelling populations (Lagwa and Akpugoeze) of Sclater's monkey (Cercopithecus sclateri), a threatened species endemic to southeastern Nigeria, and compared these data to previous census results. We recorded population increases in both sites: a 66% increase over 41/2 years in Lagwa (from 124 to 206 individuals) at an annual rate of 10.2%, and a 29% increase over 4 years in Akpugoeze (from 193 to 249 individuals) at an annual rate of 5.7%. Mean group size also increased in both sites. Density in Lagwa was 24.2individuals/km2, and density in a core survey area of Akpugoeze was 36-38individuals/km2. Our results may have been affected by monkey ranging and grouping patterns and improved detectability due to our revised census technique, which included secondary observers. With further work on methodology for censusing populations that occur in human-settled environments, techniques can be refined and customized to individual sites for more accurate estimates. Our investigation of Sclater's monkey in Lagwa and Akpugoeze, two sites critical for conservation of the species, indicated that both of these populations have increased, and neither faces immediate risk of extirpation. Such population growth, while encouraging, will likely exacerbate human-monkey conflict and thus should be understood in terms of potential socioeconomic impacts. © 2013 Wiley Periodicals, Inc. Source

Hamza A.,American University of Nigeria
Structural Chemistry

The conformations and exciton couplings in 5,6,11,12-tetrahydrodibenzo[a,e]cyclooctene (THDC) have been studied using resonance-enhanced two-photon ionization spectroscopy in a supersonic jet expansion. It has been estimated from the spectral analysis that 90% of THDC exists in the twist-boat (TB) conformation; the chair (C) conformer constitutes the remaining 10%. Most of the vibronic activity in the spectrum of THDC is associated with the symmetric flapping of the aromatic rings of the TB conformer. The observed S 1/S 2 exciton splitting of the TB conformer is 100 cm -1. The S 1/S 2 transition of the C conformer is found to be forbidden. The exciton splittings of the C and TB conformers were estimated by the spectral analysis of two deuterated isotopomers of THDC. The estimated exciton splittings of the C and TB conformers are 14.7 and 101.9 cm -1, respectively. The supramolecular model of bichromophores with identical chromophores at the CIS/6-31+G(d)//HF/6-31+G(d) level of theory predicted electronic coupling energies that are very close to the experimental exciton coupling energies. © Springer Science+Business Media, LLC 2010. Source

Hamza A.,American University of Nigeria
Structural Chemistry

The molecular conformations of jet-cooled 2-methylindan (2MI) and 2-phenylindan (2PI) have been studied using resonant-enhanced two-photon ionization spectroscopy in combination with ab initio calculations. Both axial (2MI ax) and equatorial (2MI eq) conformers of 2MI have been observed. A 2MI eq/2MI ax conformer ratio of 2.3 was estimated at 298 K, leading to the energy difference, of 0.49 kcal/mol. Ab initio calculations predicted three stable conformers of 2PI: Two equatorial conformers (2PI eq0 and 2PI eq90), and one axial conformer (2PI ax). Only the axial conformer of 2PI (2PI ax) was experimentally observed. The indan ring of 2PI ax is slightly more planar than the indan rings of the two equatorial conformers of 2PI because of the intramolecular C sp2-H/π interactions in 2PI ax. The equatorial conformers of 2PI relax to the more stable axial conformer because of the high pre-expansion temperature (383 K), and relatively low barrier (1.68 kcal/mol) to axial-equatorial interconversion. The barrier (2.33 kcal/mol) to axial-equatorial interconversion in 2MI is high enough to prevent conformational relaxation at the pre-expansion temperature of 298 K. Intramolecular C-H/π interactions are found to be more important in determining the conformational preference of 2PI than 2MI; this can be attributed to the higher acidity of the C sp2-H bond than that of C sp3-H bond. © 2010 Springer Science+Business Media, LLC. Source

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