Bird diversity in hedgerows

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Heavy metals load in tilapia species: a case study of Jakara river and Kusalla dam, Kano state, Nigeria

Between August and September 2009, twenty four (24) Tilapia species, twelve (12) from each site were sampled from Jakara River and Kusalla dam in Kano, Nigeria with the view to determine the level of some heavy metals in the muscles of the fishes so as to assess their safety or otherwise for human consumption. The weight of each of the samples was determined using Gallenkamp weighing balance and recorded to the nearest grams. The fishes were dissected to separate the muscles from head, viscera and bones. Five grams of the muscle from each sample was digested using concentrated nitric acid and hydrogen peroxide solutions prepared in the ratio of 1:1. The digested samples were aspirated using 210 VGP Atomic Absorption Spectrophotometer from which copper, zinc and lead were determined. The fish samples analysed from Jakara River had the mean copper, zinc and lead concentrations of 0.46+0.14mg/kg, 15.83+5.05 mg/kg and 0.57+0.20mg/kg and those from Kusalla dam had the means of 0.38+0.31mg/kg, 12.04+2.99 mg/kg and 0.54+0.29mg/kg respectively. Comparison of the above means with FAO standards for Cu (30mg/kg), Zn (30mg/kg) and Pb (0.50mg/kg) revealed that the mean concentrations of copper and zinc are safe for human consumption. However, the mean lead concentration exceeded the limit prescribed for human consumption. This suggests the possible adverse health effect such as damage to the gastrointestinal tract and chronic damage to the Central Nervous System among others that the people consuming Tilapia species from both study sites could be exposed to. It was recommended that considerable attention be paid to the lead content in fresh water fish at both sites by appropriate authorities due to its possible health implication on the consumers. Furthermore, continuous monitoring of heavy metals load in fish will be needed in Jakara River and Kusalla dam. Similarly, measures should be put in place to control the inflow of raw effluent into the river as they are largely the possible sources of these metals

A decentralized proportional-integral sliding mode tracking controller for a 2 D.O.F robot arm

Trajectory tracking with high accuracy is a very challenging topic in direct drive robot control. This is due to the nonlinearities and input couplings present in the dynamics of the arm. This paper deals with the tracking control of a class of direct-drive robot manipulators. A robust Proportional-Integral (PI) sliding mode control law is derived so that the robot trajectory tracks a desired trajectory as closely as possible despite the highly non-linear and coupled dynamics. The controller is designed using the decentralized approaches. Application to a two degree of freedom direct drive robot arm is considered

Pengembangan Multimedia dalam Pembelajaran Bahasa Mandarin untuk Kecakapan Menulis Kosakata di Kelas X SMA

One foreign language option in the national education curriculum is mandarin. The highest level of difficulty experienced by students is the writing competence. Therefore, the developmental research aimed at producing mandarin instructional multimedia to enhanced students competences in writing. The approach used in the developmental research emloyed a qualitative approach. Data collection techniques such as interviews, observation, and study documents. Analysis of the data by calculating the percentage of indicators and qualitative descriptions. Developmental Multimedia begins with preparing prescriptions of learning task in learning design based on characteristic and learning behavior of students, then design the storyboard, and continued with the development of instructional multimedia

Performance of metakaolin based geopolymer concrete at elevated temperature

Due to the carbon dioxide emission arising from the production of cement, alternative concrete that is environmentally friendly such as metakaolin geopolymer concrete have been developed. However, the performance of metakaolin based geopolymer concrete (MKGC) when exposed to aggressive environment particularly elevated temperature has not been investigated. Therefore, this paper assessed the performance of MKGC exposed to elevated temperatures. MKGC cube specimens of grade 25 were produced using a mix ratio of 1:1.58:3.71.After preparing the specimens, they were placed in an electric oven at a temperature of 60oC for 24 hours. Thereafter, the specimens were stored in the laboratory at ambient temperature for 28 days. The specimens were then exposed to elevated temperatures of 200, 400, 600 and 800oC. After exposure to elevated temperatures, the MKGC specimens were subjected to compressive strength, water absorption and abrasion resistance tests. Results show that at 600 and 800oC, the MKGC lost a compressive strength of 59.69% and 71.71% respectively. Higher water absorption and lower abrasion resistance were also observed. Keywords: Cement, Compressive Strength, Metakaolin Concrete, Elevated Temperature

T-ABSO and strongly T-ABSO Fuzzy second submodules and Related Concepts

In this search, we present the concepts T-ABSO fuzzy second submodules and strongly T-ABSO fuzzy second submodules, as well as some basic properties and characterizations of these concepts under the categories of multiplication fuzzy modules, cocyclic fuzzy modules, and comultiplication fuzzy modules. We also address the relationship among T-ABSO fuzzy second submodules, strongly T-ABSO fuzzy second submodules, and quasi T-ABSO fuzzy second submodules. Also, we study these concepts with other related fuzzy submodules

Perinatal arterial ischaemic stroke: an update with literature review

Perinatal arterial ischaemic strokes are a major cause of morbidity in the neonatal period and leads to significant neurological morbidity. It is however under recognized as an entity and usually missed till the baby is 3-4 months of age when they first present with hemiplegia. Perinatal arterial ischaemic strokes are not reported from our country and this may be due to the fact that neurodiagnostic modalities were not available until the last few years. Even now this is not available in the smaller cities of our country. In this review we will discuss the common issues related to etiology and pathogenesis in perinatal arterial ischaemic stroke. The management and the prognosis are also reviewed especially discussing the factors that affect the long term prognosis