DESIGN AND IMPLEMENTATION OF A VIRTUAL COMPUTING ENVIRONMENT FOR SCHOOLS AND OFFICES

Aderemi, Adeyemi

Report of Mixed Infection of Infectious Bursal Disease and Chicken Infectious Anaemia Viruses

Infectious bursa disease (IBD) was tentatively diagnosed from an experimental cockerel flock. Clinical signs observed included dullness, diarrhoea characterized by greenish yellow colour and spiking mortality lasting four days. Post-mortem examination results showed pale and slightly enlarged liver and kidney, enlarged and haemorrhagic bursa, petechia haemorrhages on the spleen, keel and thigh muscles and thymus atrophy. Pale liver, thymus atrophy and haemorrhages in the bursa could also be presented in Chicken Infectious Anaemia (CIA) infection. The organs (Bursa, kidney, thymus and liver) from where the infected birds were further screened for IBD and CIA viruses using the polymerase chain reaction technique and were positive for both. This confirms IBD and CIA are responsible for the losses in the flock. This implies that many CIA infections or its mixed infection may be mistaken for IBD alone if no confirmatory diagnosis is carried out, since most post-mortem lesions presenting extensive syndrome are considered to be caused by IBD. &nbsp

AN ONTOLOGY-BASED KNOWLEDGE REPRESENTATION USING ANALYTIC HIERARCHY PROCESS FOR ENHANCING SELECTION OF PRODUCT PREFERENCES

Product alternatives, which emerges from large number of websites during searching, accounts for some hesitation experienced by customers in selecting satisfying product. As a result, making useful decision with many trade-off considerations becomes a major cause of such problem. Several approaches have been employed for product selection such as, fuzzy logic, Neuro-fuzzy, and weighted least square. However, these could not solve the problem of inconsistency and irrelevant judgement that occur in decision making. In this study, Ontology-based Analytic Hierarchy Process (AHP) was used for enhancing selection of product preferences. The model involved three fundamental components: product gathering, selection and decision making. Ontology Web Language (OWL) was utilized to define ontology in expressing product information gathering in a standard and structured manner for the purpose of interoperability while AHP was employed in making optimal choices. The procedure accepts customers’ perspectives as inputs which are classified into criteria and sub-criteria. Owl was created to foster customers’ interaction and priority estimation tool for AHP in order to generate the consistency ratio of individual judgements. The model was benchmarked with Geometric Mean (GM), Eigenvector (EV), Normalized Column Sum (NCS) Weighted Least Square (WLS) and Fuzzy Preference Programming (FPP). First and second order total deviations and violation rate were the performance parameters evaluation with AHP. The results showed that the minimum and maximum units of products are 2,452and 3,574, respectively. These implied that the proposed model was consistent, relevant and reflected a non-violation of judgment in selection of product preferences. &nbsp

SHORT COMMUNICATION: HYDROCARBON ACCUMULATION AND DISCHARGE BY THE CRAYFISH IN SOME RIVERS OF LAGOS, NIGERIA

Crayfishes exposed to 14C-naphthalene-5% of an aqueous fraction of crude oil in open non-aerated glass jars for 4 h at 25 0C showed no significant differences (P > 0.25) in the amount of naphthalene uptake. Different parts of the crayfishes were quantified for naphthalene uptake and cephalothorax containing hepatopancreas (a food absorption organ) was found to have greater uptake than the tail flesh or tail skeleton. Release of the oil from the crayfishes that were exposed for 1, 2, 3 or 4 h and later placed in open non-aerated jars containing oil-free water showed greater loss of most of the 14C activity during the first 24 h, there was little losses at 48, 72 and 96 h. There was significant volatilization (P < 0.04) of 14C-naphthalene in a 5% of crude oil placed in open, non-aerated, oil-free glass jars for 24 h at 25 0C. (Received May 2, 2001; revised October 19, 2001) Bull.Chem.Soc.Ethiop. 2001, 15(2), 167-17

PhyloChromoMap, a Tool for Mapping Phylogenomic History along Chromosomes, Reveals the Dynamic Nature of Karyotype Evolution in Plasmodium falciparum

The genome of Plasmodium falciparum, the causative agent of malaria in Africa, has been extensively studied since it was first fully sequenced in 2002. However, many open questions remain, including understanding the chromosomal context of molecular evolutionary changes (e.g., relationship between chromosome map and phylogenetic conservation, patterns of gene duplication, and patterns of selection). Here, we present PhyloChromoMap, a method that generates a phylogenomic map of chromosomes from a custom-built bioinformatics pipeline. Using P. falciparum 3D7 as a model, we analyze 2,116 genes with homologs in up to 941 diverse eukaryotic, bacterial and archaeal lineages. We estimate the level of conservation along chromosomes based on conservation across clades, and identify “young” regions (i.e., those with recent or fast evolving genes) that are enriched in subtelomeric regions as compared with internal regions. We also demonstrate that patterns of molecular evolution for paralogous genes differ significantly depending on their location as younger paralogs tend to be found in subtelomeric regions whereas older paralogs are enriched in internal regions. Combining these observations with analyses of synteny, we demonstrate that subtelomeric regions are actively shuffled among chromosome ends, which is consistent with the hypothesis that these regions are prone to ectopic recombination. We also assess patterns of selection by comparing dN/dS ratios of gene family members in subtelomeric versus internal regions, and we include the important antigenic gene family var. These analyses illustrate the highly dynamic nature of the karyotype of P. falciparum, and provide a method for exploring genome dynamics in other lineages

DETECTION AND SEROTYPING OF MAREKS DISEASE VIRUS IN DISEASED CHICKENS IN ABEOKUTA

Outbreaks of Marek’s disease (MD) in vaccinated flocks still occur sporadically and lead to economic losses. This study reports the detection of serotypes 1 and 3 Marek’s disease virus using molecular techniques in pullets showing clinical signs of the disease. An enzyme-linked immunosorbent assay (ELISA) was applied to evaluate the antibody response of chicks and the diseased pullets from the same parent stock against Marek’s disease (MD) at 4 and 21weeks of age respectively. Despite vaccination at day old, antibody titre in the chicks was negative while it was highly variable in the diseased pullets. From the results, the susceptibility of previously vaccinated birds to the pathogenic strain of MDV indicates inappropriate vaccination at day old and a call for concern in the poultry industry. It is therefore recommended that serology be carried out on birds to determine their immune status before and after MD vaccination. &nbsp

Suitability Assessment of Soils around Forestry Research Institute of Nigeria (FRIN), Ibadan for Maize Production: A Parametric Analyses

The sustainable use of soil resources requires extensive knowledge about its morphology and other properties. The study was carried out to evaluate the suitability of soils for maize production in Forestry Research Institute of Nigeria’s (FRIN), environment, Ibadan, using the parametric method. Four profile pits were dug, described and the soil samples collected and analyzed for particle size distribution, pH, organic matter, total nitrogen, available phosphorus, exchangeable acidity, exchangeable bases and extractable micro nutrients. The textures of the soils were loamy sand, sandy loam and sandy clay loam which varied in response to changes in slope and drainage position. The soil’s pH ranged from strong to slightly acidity (4.32 – 6.75). Organic matter (17.2 -61.2g kg-1), total exchangeable base and total nitrogen (0.7 – 3.1g kg-1) were high, while the extractable micro nutrients; Fe (37 – 67mg kg-1), Cu (7 – 13mg kg-1), Mn (5 – 142mg kg-1) and Zn (38 -134mg kg-1) were at toxic level. Suitability evaluation of the soil using parametric approach shows that the soils are presently not suitable (NS) for the cultivation of maize, while, the potential of suitability of the soil for maize cultivation was ranked marginally suitable (S3). The soils of the study area were classified as Egbeda association which is not currently suitable for maize production, because of its present status. However, the soils suitability potential can be improved through conservative agronomic practices and also to prevent rapid degradation

EVALUATION OF MATERNALLY-DERIVED ANTIBODIES AGAINST NEWCASTLE DISEASE VIRUS IN DAY-OLD CHICKS IN ABEOKUTA, OGUN STATE

High maternally-derived antibodies (MDA) against Newcastle disease virus (NDV) in chickens can interfere with active immunity at early age. This study was conducted to assess the titre of MDA in chicks against NDV from two poultry breeder farms. Twenty-six blood samples were collected from day-old chicks randomly selected from two poultry breeding farms and forty blood samples were collected from the parent stocks of the same farms. The vaccination record of the parent stocks were collected while the antibody titres of the birds were estimated using Haemagglutination Inhibition (HI) test. The geometric mean titre (GMT) of MDA against NDV in chicks from Farms 1 and 2 were log 27.2 and log 27.4 respectively while the parent stocks from Farms 1 and 2 had log 27.7 and log 27.9HI units. The percentage of chicks from Farms 1 and 2 with MDA titre above protective level (&gt;log 23) were 90% and 100% respectively. It was concluded that MDA titres against ND virus was high in the chicks therefore vaccination at day one in the hatcheries and farms should be done after the immune status of the chicks are known since high MDA titre during vaccination neutralizes vaccine virus preventing active immunity.Â

Surveillance for Avian Influenza H 5 Antibodies and Viruses in Commercial Chicken Farms in Kano State, Nigeria

Abstract: Outbreaks of highly pathogenic Avian Influenza occurred previously for 3 consecutive years, 2006, 2007 and 2008, in Kano State, Nigeria, causing heavy economic losses to farmers and the government. It was against this background that Avian Influenza (AI) surveillance study in commercial poultry farms in the State was conducted. Haemagglutination Inhibition (HI) test was conducted to determine the presence of AI H 5 antibodies in 1,160 sera obtained from flocks in 33 Avian influenza affected (AF) and 25 Non Avian influenza-affected (NAF) farms. To complement the study, 320 cloacal swabs obtained from flocks in farms that were serologically positive for AI H 5 antibodies, were further subjected to Reverse Transcription-Polymerase Chain Reaction (RT-PCR), to determine if the chickens were shedding AI viruses. Of the 1,160 sera tested, 150 (12.9%) were positive for AI H 5 antibodies, with flocks in 16 (27.6%) of the farms being positive. Prevalence rates of 14.1 and 11.4% and mean antibody titres of 5.4±0.2 and 4.6±0.1 log 2 for AI H 5 antibodies were obtained for AF and NAF farms, respectively. The RT-PCR results showed that all the 320 cloacal swabs tested were negative for AI H 5 viruses. The antibodies detected between flocks in the AF and NAF farms might be attributed to vaccination and the titres determined were above the minimum protection level recommended by the OIE. It was recommended that vaccination of chickens against AI should be discouraged because it may interfere with the stamping out policy adopted by Nigeria in the control and eradication of the disease