Vol 16, No 2 , 2015-1, African Scientist

Acute toxicity study on neem (azadirachta indica, juss) leaf aqueous extract in chicken (gallus gallus domesticus)

Acute toxicity of Azadirachta indica (neem) leaf aqueous extract was tested on chickens; and the median lethal dose (LD50) was calculated. Both clinical signs, gross lesion and microscopic lesions at post mortem were recorded.

Antagonistic activities of Paecilomyces and Rhizopus species against the cocoa black pod pathogen (Phytophthora palmivora)

Two test fungal antagonists (Paecilomyces sp. and Rhizopus stolonifer) were isolated from cocoa rhizosphere and rhizoplane while the black pod pathogen (Phytophthora palmivora) was isolated from freshly infected cocoa pods. In vitro screening using the dual culture technique was conducted to assess their potential as biological control agents against the pathogen. The results revealed that in dual cultures, the test antagonists effectively checked the growth of P. palmivora. The antagonists grew faster than the pathogen and produced zones of inhibition.

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Synthesis of metal containing polymers

The remarkable growth in the applications of organic polymers in the latter half of the twentieth century can mainly be attributed to their ease of preparation, and the useful mechanical properties and unique propensity for fabrication. Polymers containing metallic elements offer a wider range of novel characteristics and provide potential access to new processible functional polymeric materials and thus, study on the synthesis and prospective applications of metallopolymers have become an area of interest to polymer chemists.

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Forest conservation policy in Edo State: An assessment of roles of forestry taskforce in realising the set objectives

The study examined the roles of task force forest in conservation in Edo state with the use of data collected from both primary and secondary sources. The data were obtained through the use of well structured questionnaires administered to 90 respondents in 15 communities and forests reserved, based on sampling intensities of 50% to elicit information on activities of task force in forest conservation. Secondary data were obtained from ministry of environment and task force head office.

A replacement problem of n unit parallel system with minimal repair options

We consider a replacement problem of n units parallel system, where a component failure is rectified by minimal repairs. We exchanged the system preventively before failure if the number of minimal repairs reaches m r m m − − − ,..., 2, 1 and is preventively replace if the sum of minimal repair reaches threshold value m . Keywords: minimal repairs, parallel system, failure,

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Behavioural patterns of rats in an open field following treatment with Artesunate plus Amodiaquine combination

Artesunate (AS) plus amodiaquine (AQ) combination is a potent artemisinin-base antimalrial drug is commercially available with different trade names. Several adverse effects including neurotoxic complaints have been ascribed to this combination. This study was to determine the behavioral pattern of rats treated with this drug in an open field. Forty matured male Wistar rats weighing 150-180g were equally grouped into four. Group A was the control and the animals received tap water placebo, while groups B, C and D were the experimental.

A method of assay for the estimation of sulphadimidine in tablets

A simple and rapid titrimetric method (Back Titration) was used in the assay of Sulphadimidine in commercial tablets. The method involves alkaline hydrolysis of Sulphadimidine to form the corresponding acid. This was followed by back titration of the excess alkali using phenolphthalein as indicator. The results of this assay method were compared with those obtained from the official nitrite titration method. Both methods yielded similar results with high percentage recoveries. The proposed method gave results that agree well with the labeled contents.

Energetic Advantages of Pause-Travel At Low Speeds

Some larval fish species do not swim continuously but forage using intermittent locomotion pattern which consist of relatively high speed swimming interspersed by pauses. This type of locomotion is known as pause-travel. In this paper, a mathematical model that examines the advantages of pause-travel over continuous swimming is developed. The results of the present calculations show that pause-travel is an efficient strategy to adopt over certain range of travel speeds.

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