Showing papers by "Cross River University of Technology published in 2008"
TL;DR: The silver catfish, Chrysichthys nigrodigitatus (Lacépède: 1803) is a highly valued food-fish included among the dominant commercial catches exploited in major rivers of Africa.
Abstract: The silver catfish, Chrysichthys nigrodigitatus (Lacepede: 1803) is a highly valued food-fish included among the dominant commercial catches exploited in major rivers of Africa. To provide useful biological data for management, samples were collected monthly between January (2005) and December (2007) in three zones: I: Upper Cross River (grassland), II: Middle Cross River (mixed forest and grassland), and III: Lower Cross River (rainforest)) along 200 km length of the Cross River, Nigeria. Data from 1 248 specimens were processed using: allometric coefficient (b), gonado-somatic index, Fulton's condition factor and diversity indices. Male dominance was observed in all populations; C. nigrodigitatus reached maturity at 11.5cm (male) and 16.7cm (female) total length. Gonado-somatic index was higher for females with a peak in the early rains. The breeding period was between April and August with mean fecundity ranging between 4522 ±1924 eggs and 20321 ± 5543 eggs. This was directly related to total length and weight by the regression models: F = 2365.88 + 560.22 log L and F = 5025.81 +56.34 log W respectively. Exponential equations for length-weight relationships were Wt=- 1.997 Lt 2.206 (Zone I), W = -2.831 Lt 3.040 (Zone II) and Wt= -2.245 Lt 2.995 (Zone III). The mean allometric coef- ficient (b) showed significant departure from cubic value (negative allometry) for Zone I while Zones II and III showed no difference, indicating isometry. Dominant items in the diet were fish and fish parts constituting 21.6% with Food Richness and Gut Repletion Index of 18 and 100% respectively, in all zones. Diet Breadth of 0.802 (Zone I), 0.922 (Zone II) and 0.910 (Zone III) indicate a high trophic flexibility that enables switching from one diet to another according to availability. Mean condition factor for males varied from 0.718 ±0.117 minimum in Zone I to 0.996 ±0.062 maximum in Zone III. Forest inland wetlands (Zone II and III) of Cross River provided better condition for C. nigrodigitatus. Rev. Biol. Trop. 56 (4): 1785-1799. Epub 2008 December 12.
42 citations
TL;DR: The results showed that concentrations of lead in excess of 0.30 µg l−1 can be potentially harmful to Daphnia magna and Cyclop spp respectively as mentioned in this paper.
Abstract: Acute toxicity of Pb to the water flea; (Daphnia sp) and Copepod, (Cyclop sp) both important component of zooplankton diet of fish was determined by static assay. A positive relationship between percentage mortality and exposure concentration was found in all tests. Mean 24-h LC50, 48-h LC50 and 96-h LC50 values were 2.51 ± 0.0.04 mg l−1, 1.88 ± 0.06 mg l−1 and 1.65 ± 0.19 mg l−1 for Daphnia spp and 3.11 ± 0.03 mg l−1, 2.97 ± 0.05 mg l−1 and 2.61 ± 0.09 mg l−1 for Cyclop spp, respectively. For all tested species did the LC50 values decrease with time; the decrease was more marked for Daphnia spp. Observed symptoms include spiral movement followed by change of body colour to white and rapid disintegration of the skin. The Daphnia spp. appear to be more sensitive to Pb poison than Cyclop spp. The results showed that concentrations of Lead (Pb) in excess of 0.19 mg l−1 and 0.30 mg l−1 can be potentially harmful to Daphnia magna and Cyclop spp respectively.
39 citations
TL;DR: In this article, an exposition of foreign exchange market and economic growth in an emerging economy -the Nigerian case is presented, focusing on the implications of exchange rate movement on economic growth, and maintaining that exchange rate policy should be designed to bridge the savings investment gap so as to enhance government revenue and reduce the fiscal Lacuna through the curtailing of deficit geared at increased and sustained economic growth.
Abstract: This study is an exposition of foreign exchange market and economic growth in an emerging economy - the Nigerian case. The paper focuses on the implications of exchange rate movement on economic growth. The ordinary least square (OL5) technique was adopted using time series data on exchange rate movement, volatility of exchange rate (EXCHR) labor force, gross domestic investment and technology, volatility of exchange rate is measured by three years moving average of standard deviation of real exchange rate. The paper maintains that in view of the positive relationship between exchange rate, volatility and economic growth in Nigeria, exchange rate policy should be designed to bridge the savings investment gap so as to enhance government revenue as well as reduce the fiscal Lacuna through the curtailing of deficit geared at increased and sustained economic growth. Gross domestic investment should also be sustained since this leads to significant economic development.
26 citations
TL;DR: Results revealed a trimodal peak in Vibrio counts, coinciding with meteorological changes and the hot periods of the year, and provide a guide for effective control of associated cholera epidemics.
Abstract: The prevalence of Vibrio species in shellfish and their seasonal variability in the Great Kwa River estuary (GKWE) were examined. Results revealed a trimodal peak in Vibrio counts, coinciding with meteorological changes and the hot periods of the year. The estuary was constantly faecally polluted, coupled with high rates of infection of shellfish by V. parahaemolyticus 42 (13.6%), V. cholerae non-01 29 (9.4%) and V. alginolyticus 22 (7.1%), thus posing a health risk. The observed seasonal variability and prevalence of Vibrio species infection are of epidemiological significance, and provide a guide for effective control of associated cholera epidemics.
20 citations
TL;DR: In this article, cellulosic and crustacean filler materials were used to study their effects on polyvinyl-acetate (PVAC) emulsion wood adhesives, and the elastoplastic behavior of the filler-treated PVAC emulsion was studied using differential scanning calorimetry and dynamic mechanical thermal analysis.
Abstract: Cellulosic and crustacean filler materials were used to study their effects on poly(vinyl-acetate) (PVAC) emulsion wood adhesives. The elastoplastic behavior of the filler-treated PVAC emulsion was studied using differential scanning calorimetry and dynamic mechanical thermal analysis. The result revealed that the glass transition temperature (Tg) of the filler-treated polymer is not significantly changed by the addition of the filler materials, whereas the tensile modulus, adhesive hardness, and the stiffness were markedly changed. The viscosity of the emulsions and their performance on wood surfaces were greatly affected by fillers. The cellulosic fillers have high oil-absorption capacity, hence increased viscosity to a greater extent than the case with crustacean-based filler materials, which have faster coalescence but yield mechanically weaker films. The acidity of the fillers influenced the setting time for wood adhesive bonding.
2 citations
TL;DR: Results showed that while ingestion of coconut milk and coconut water increased the values of protein and protein/RNA ratios, there was a decrease in ALT and AST activities, opposite to those produced by caffeine alone and may prevent the adverse effects attributed to caffeine.
Abstract: The effects of interactions between coconut products and caffeine on the induction of drug-metabolizing enzyme in Wistar albino rats were studied. Twenty rats were randomly divided into four groups: (Group 1) control received via oral route a placebo (4 mL distilled water). Groups 2–4 were treated for a 14-day period, respectively, with 50 mg caffeine/kg body weight (BW), 50 mg caffeine/kg plus 50 mg coconut water/kg, or 50 mg caffeine/kg plus 50 mg coconut milk/kg in a 4 mL volume via gastric intubation. One day after the after the final exposure, the animals were euthanized by inhalation of an overdose of chloroform. The blood of each rat was collected by cardiac puncture, and the liver of each was harvested and processed to examine several biochemical parameters, including total protein and RNA levels, protein/RNA ratios, and the activities of alanine and aspartate aminotransferases (ALT and AST, respectively). Results showed that while ingestion of coconut milk and coconut water increased the values o...
2 citations
TL;DR: The accounting profession has received very bad publicity in the media over the past decade, and with some justification as discussed by the authors, and different investigators place emphasis on a variety of phenomena that created the environment in which some accounting firms disappeared and the reputation of the entire profession was tarnished.
Abstract: The accounting profession has received very bad publicity in the media over the past decade, and with some justification. The forces at work were numerous and complex and different investigators place emphasis on a variety of phenomena that created the environment in which some accounting firms disappeared and the reputation of the entire profession was tarnished. Current practices still pose further decline in professionalism with threats to further erode public trust in the profession. This paper attempts to identify the core of the problem. It also makes some suggestions on how the profession can prevent a recurrence of the embarrassments to the profession, and how educators may better prepare entrants to the profession.