Cost Entropy and Expert System Approach to Modeling Cost Smoothing System in Reinforced Concrete Office Building Projects Procurement

The main aim of this research work is to develop an expert system approach to cost smoothing model in reinforced concrete office building project procurement. An econometric model which incorporates exigency escalator and inflation buffer, with entropy threshold for a typical reinforced concrete office building, useful at tendering and construction stages of building projects  was developed in this study. As built and bill of quantity value of twenty (20) building projects initiated and completed within 2008 and 2009 were used at random. Elemental dichotomies within the context of early and late constructible elements with speculated prediction period was used, taken into consideration the present value of cost. This attributes would enable a builder or contactor load cost implication of an unseen circumstance even on occasion of deferred cost reimbursement with the aid of average entropy index developed for each project elements. The model was further validated with new samples and discovered to be of high Eigen and contingency coefficient values. The model could help in cost smoothing at different stages of reinforced concrete office building which could further aid cost overrun prevention.   Keywords: Expert system, Smoothing, Entropy, Dichotomy

Light microscopic detection of Plasmodium falciparum in vitro through Pf histidine rich protein 2 (HRP 2) gold conjugate labeling: Rapid diagnosis of cerebral malaria in humans

Plasmodium falciparum (Pf) has been found to be the deadliest of all the known species of the parasite capable of infecting humans; this is because it is capable of causing severe cerebral tissue damage. This study was carried out to demonstrate the parasite in the host blood in vitro through immunogold labeling using antibodies against Plasmodium falciparum histidine rich protein 2 (HRP 2); a major metabolite released during the cause of the parasite infection and feeding in the erythrocyte. 12 known Pf positive samples were obtained from across the six geopolitical zones of Nigeria and were further characterized by Geimsa thick and thin film for parasite identification parasite count expressed as parasites/l of blood. An average of 400 parasites/l of blood was obtained in each of the samples used for this study. Pf-HRP 2 antibody was conjugated to freshly prepared colloidal gold of particle size 40nm. The conjugation process was blocked with bovine serum albumin (BSA) and the conjugate itself preserved by 1% glycerol and 0.01% sodium azide. The parasite count was titrated against the Pf-HRP 2gold conjugate and was analyzed under the light microscope with a fluorescent filter. Reactivity and specificity of Pf-HRP 2 gold conjugate was found to be highly specific and gave direct identification of the erythrocytes infected with the parasite. A good contrast was also obtained between uninfected erythrocytes, parasite and the infected erythrocytes

P53, Bax and Cathepsin D Dysregulation in Neurons Subjected to Cyanide Toxicity and Oxygen Deprivation

Cyanide is a potent neurotoxin capable of potentiation NMDA R1 (N-methyl-D-aspartate receptor 1) a form of glutamate receptor that is calcium gated, thus causing excitotoxicity. It is also well established that the glutamate-glucose exchange is dependent on the activity of the Na + /K + ATPase pump, thus we examine the role of the Na + /K + pump in the metabolism of the neuron during cyanide toxicity. Six separate perfusion set up of the rat brain cortical tissues were made with ACSF (ACSF, ACSF+KCN, ACSF+KCN + pump blocker, ACSF + pump blocker). The tissues were perfused for duration of 180 minutes. The tissues were processed immunohistochemically using antibodies against p53,Bax and Cathepsin D (CD) to demonstrate disregulation of cell cycle proteins associated with the induced DNAbreakage as a result of cyanide toxicity. The pumpblockers (methyldigoxin and promethazine) induced excitotoxicity when used in culture, and amplified cyanide toxicity when combined with KCN. Cell death induced by toxicity of cyanide and the blockade of the Na/K ATPasepump has been seen to be complimentary in driving the toxicity effects that drives the cell into apoptosis.The tumor suppressor/apoptosis inducing factors p53 and Bax were over expressed while cathepsin was suppressed to show that the cells are apoptotic as against an increased cathepsin D level that would have implied senescence

Indoor comfort and adaptation in low-income and middle-income residential buildings in a Nigerian city during a dry season

This paper investigates occupants' comfort, adaptation and their responses during the dry season in low-income to middle-income residential buildings in Abuja, Nigeria. The study aims to provide empirical data on occupants' comfort through evaluating 171 households in four different locations in Abuja. The study considered a combination of different research methods for data collection. Post-occupancy surveys were used to evaluate the buildings and residents' adaptation within the thermal environment. Thermal comfort surveys were also carried out in eight low-income residential households to assess occupants' perception of the thermal environment. Based on the short duration of the physical measurements, building simulation was also used to examine thermal comfort of occupants for an extended period. The Post Occupancy Evaluation (POE) results revealed over 70% of the occupants were dissatisfied with their thermal environment. The comfort surveys reported similar results with over 65% of the responses revealed being ‘uncomfortably warm’. The results showed an overall mean temperature of all the measured case studies to be 31.7 °C and the average temperature (predicted) of 30.7 °C. The neutral temperatures were in a range of 28°C–30.4 °C compared to the preferred temperature range of 27.5°C–29.4 °C. The prevalence of thermal discomfort highlights the need to explore the possibilities of reducing internal temperatures, particularly by passive means (fabric, shading, insulation etc.) given the need to avoid or reduce the need for air conditioning to make the buildings energy-efficient for low to middle income groups

Social factors affecting seasonal variation in bovine trypanosomiasis on the Jos Plateau, Nigeria

BACKGROUND: African Animal Trypanosomiasis (AAT) is a widespread disease of livestock in Nigeria and presents a major constraint to rural economic development. The Jos Plateau was considered free from tsetse flies and the trypanosomes they transmit due to its high altitude and this trypanosomiasis free status attracted large numbers of cattle-keeping pastoralists to the area. The Jos Plateau now plays a major role in the national cattle industry in Nigeria, accommodating approximately 7% of the national herd, supporting 300,000 pastoralists and over one million cattle. During the past two decades tsetse flies have invaded the Jos Plateau and animal trypanosomiasis has become a significant problem for livestock keepers. Here we investigate the epidemiology of trypanosomiasis as a re-emerging disease on the Plateau, examining the social factors that influence prevalence and seasonal variation of bovine trypanosomiasis. METHODS: In 2008 a longitudinal two-stage cluster survey was undertaken on the Jos Plateau. Cattle were sampled in the dry, early wet and late wet seasons. Parasite identification was undertaken using species-specific polymerase chain reactions to determine the prevalence and distribution of bovine trypanosomiasis. Participatory rural appraisal was also conducted to determine knowledge, attitudes and practices concerning animal husbandry and disease control. RESULTS: Significant seasonal variation between the dry season and late wet season was recorded across the Jos Plateau, consistent with expected variation in tsetse populations. However, marked seasonal variations were also observed at village level to create 3 distinct groups: Group 1 in which 50% of villages followed the general pattern of low prevalence in the dry season and high prevalence in the wet season; Group 2 in which 16.7% of villages showed no seasonal variation and Group 3 in which 33.3% of villages showed greater disease prevalence in the dry season than in the wet season. CONCLUSIONS: There was high seasonal variation at the village level determined by management as well as climatic factors. The growing influence of management factors on the epidemiology of trypanosomiasis highlights the impact of recent changes in land use and natural resource competition on animal husbandry decisions in the extensive pastoral production system

A longitudinal survey of African animal trypanosomiasis in domestic cattle on the Jos Plateau, Nigeria:prevalence, distribution and risk factors

BACKGROUND: Trypanosomiasis is a widespread disease of livestock in Nigeria and a major constraint to the rural economy. The Jos Plateau, Nigeria was free from tsetse flies and the trypanosomes they transmit due to its high altitude and the absence of animal trypanosomiasis attracted large numbers of cattle-keeping pastoralists to inhabit the plateau. The Jos Plateau now plays a significant role in the national cattle industry, accommodating approximately 7% of the national herd and supporting 300,000 pastoralists and over one million cattle. However, during the past two decades tsetse flies have invaded the Jos Plateau and animal trypanosomiasis has become a significant problem for livestock keepers. METHODS: In 2008 a longitudinal two-stage cluster survey on the Jos Plateau. Cattle were sampled in the dry, early wet and late wet seasons. Parasite identification was undertaken using species-specific polymerase chain reactions to determine the prevalence and distribution bovine trypanosomiasis. Logistic regression was performed to determine risk factors for disease. RESULTS: The prevalence of bovine trypanosomiasis (Trypanosoma brucei brucei, Trypanosoma congolense savannah, Trypanosoma vivax) across the Jos Plateau was found to be high at 46.8% (39.0 – 54.5%) and significant, seasonal variation was observed between the dry season and the end of the wet season. T. b. brucei was observed at a prevalence of 3.2% (1% – 5.5%); T. congolense at 27.7% (21.8% - 33.6%) and T. vivax at 26.7% (18.2% - 35.3%). High individual variation was observed in trypanosomiasis prevalence between individual villages on the Plateau, ranging from 8.8% to 95.6%. Altitude was found to be a significant risk factor for trypanosomiasis whilst migration also influenced risk for animal trypanosomiasis. CONCLUSIONS: Trypanosomiasis is now endemic on the Jos Plateau showing high prevalence in cattle and is influenced by seasonality, altitude and migration practices. Attempts to successfully control animal trypanosomiasis on the Plateau will need to take into account the large variability in trypanosomiasis infection rates between villages, the influence of land use, and husbandry and management practices of the pastoralists, all of which affect the epidemiology of the disease

Effects of aqueous extracts of Zanthoxylum macrophylla roots on membrane stability of human erythrocytes of different genotypes

The effects of aqueous extract of Zanthoxylum macrophylla (formerly Fagara xanthoxyloides ) roots on the membrane stabilities of human erythrocyte from HbAA, HbAS and HbSS blood were investigated. The determination of mean corpuscular fragility (MCF), which is the concentration of saline causing 50% haemolysis of the erythrocytes, showed that the aqueous plant extract increased the MCF values of the various erythrocytes. There was no significant difference (p>0.05) between the MCF values of HbAA and HbAS erythrocytes. However, significant difference (p<0.05) was noted between HbAA and HbSS erythrocytes. Percentage stabilization, calculated from the MCF values showed stabilization by the plant extract of 11.11, 10.30 and 14.39 % for the erythrocytes from HbAA, HbAS and HbSS, respectively. At a concentration of 400 μM, phenylalanine, a known anti-sickling compound, produced a stabilization of 17.85% for HbSS erythrocyte under the same experimental conditions used for the aqueous plant extract. Blood viscosity studies indicated a decrease in viscosity of the HbSS blood by the aqueous extract and this reduction was significantly different (p<0.05) from that for HbAA and HbAS bloods. The plant extract also showed pronounced reversion of 2% sodium metabisulphite-induced sickling, an effect also observed with phenyl alanine (400 μM). These findings suggest that the plant extract has some role in stabilizing the erythrocyte membranes, thus providing possible molecular basis for earlier reports on the anti-sickling effects of Zanthoxylum macrophylla and its use in the management of the sickle cell disease

In vitro effects of aqueous extracts of Zanthoxylum macrophylla roots on adenosine triphosphatases from human erythrocytes of different genotypes

The in vitro effects of aqueous extracts of Zanthoxylum macrophylla roots on the activities of three ATPases (Na+, K+- ; Ca2+- ; and Mg2+-ATPases) were investigated in membrane preparations from human erythrocytes of HbAA, HbAS and HbSS bloods. The activities of these membrane-bound enzymes were determined in the presence of varying concentrations of the plant extract. The results indicated that for Na+, K+- and Ca2+-ATPases, a dose-dependent activation of the three enzymes by the aqueous plant extract occurred. The trend for the different genotypes was HbSS>HbAS>HbAA. The activations were significant (p<0.05) when compared with activities obtained in the absence of the plant extract. Phenylalanine, a known anti-sickling agent, at varying concentrations (200-800μM) produced similar activating effect. In contrast, the extract inhibited the Mg2+-ATPase activity in a dose-dependent manner with a trend of HbSS>HbAS>HbAA. The inhibitions seen were significant (p<0.05) in comparison with activities in the absence of the plant extract. Phenylalanine produced similar effect for Mg2+-ATPase. These findings in this study suggest that differences in the ATPases of the different genotypes may account for the reports of other workers on the involvement of ion transport as a factor in the physiological manifestation of sickle cell disease. The findings are also significant to an understanding of the molecular basis for the use of the aqueous extract of Z. macrophylla roots in the management of sickle cell disease

Work Stress among Professionals in Building Construction Industry in Nigeria

This study was undertaken to identify key stress factors among professionals in building construction industry in Nigeria. This is in view of the fact that to date, very little is known about work stress among professionals in building construction industry in this country. The study involved the administration of questionnaire to 107 professionals including architects, builders, civil/structural engineers and quantity surveyors randomly selected from 60 ongoing building projects in Anambra, Ogun and Kaduna States, Nigeria. The data was analysed using descriptive statistics, and findings show that the principal sources of stress were high volume of work, uncomfortable site office environment, lack of feedback on previous and ongoing building projects, and variations in the scope of work in ongoing building projects. The paper suggests that taking responsibility for work which one has adequate capacity to handle, establishing realistic budgets and time frame for project delivery, provision of spatially adequate, visually and thermally comfortable site offices, adoption of appropriate job design practice and education of professionals on stress management strategies will reduce the incidence of stress among professionals in building industry in Nigeria.