Construction of An Automatic Power Switch using Infrared Motion Sensor

In public and private institutions the problem of switching off light and other appliances wherever it is not needed is a concern. In Covenant University, the issue led to various rules that try to limit the way light is being used in the halls of residence, classrooms and other buildings. The main aim of this project is to conserve energy. This project presents the construction of a power control system which can detect the approach of a person, and then turn the power of a room on. The project involves four stages: the power supply stage, the sensor stage, the arduino stage and the switching mechanism stage. The power supply stage involves the supply of power to the arduino and the sensor. The sensor stage consist the passive infrared sensor which is the core part of the project. It detects the radiated heat energy from a person and converts the energy to an electrical signal which is sent to the arduino for processing. The arduino then processes the signal and sends a specific voltage to the relay that actuates the power switch to on. When nobody is detected the power is turned off. Conclusively, the constructed energy control system prevents energy wastage in the lecture halls, classrooms and other buildings

Development of Bi-modal exercise bicycle for physical fitness and rehabilitation

Exercise bicycles are used for kinesiological activities; to increase general fitness, and for training for cycling events. They are also used for weight loss. The aim of this study is to produce a special exercise bike which allows for both upper and lower limbs pedalling either independently or otherwise. The manufacturing processes employed in the design involved the use of AutoCAD design suite and other production engineering processes which included material selection and acquisition, cutting, welding and drilling. The device was tested for both comfort and effectiveness for cardiac rehabilitation using the rate of heartbeat as the test parameter. A strong positive correlation was found (p<0.001; r=0.962) between the two heart rate tests. An ergonomic evaluation of the bi-modal exercise bike showed 98% suitability of the seat-pedal height with the knee height of the study population and 100% suitability of the seathandle post height with the buttock-knee length of the population. In conclusion, the goal of developing a bi-modal exercise bike that permits simultaneous upper and lower limbs pedalling was realised.Keywords: exercise bicycle; cycling; ergometer; fitness; rehabilitation

GENDER AND LEVELS OF ATTAINMENT OF SCIENTIFIC LITERACY AMONG SCIENCE STUDENTS UNDER CONSTRUCTIVIST INSTRUCTIONAL MODEL

The study investigated levels of attainment of scientific literacy by junior secondary (8th grade) male and female students. Quasi-experiment of non- equivalent control group design was used. A total of 162 students were selected by purposive sampling of four coeducational schools out of twenty three in Ohafia Local Government Area, Abia state, Nigeria. In each of the four schools, an intact class was randomly selected. These were randomly assigned, two to experimental and control groups. Research questions were answered using mean and standard deviations and the hypotheses tested using ANCOVA. TOSL instrument for data collection had parts A and B. Reliability Coefficient of part A was established using Spearman rank order correlation and B using Kuder-Richardson formula 20(K-R). The internal consistencies were 0.69 and 0.72. The findings showed that constructivist instruction enhanced students’ attainment of scientific literacy irrespective of their sexes. Based on the findings recommendations were made

Contribution of small and mediumenterprisesto economic development: Evidencefroma transitingeconomy

The focusofthisresearchwastopresentadataarticleonthe contribution ofSMEstoeconomicdevelopmentinatransiting economy.Descriptiveresearchdesignwasadoptedinthisstudy. Data wereobtainedfrom600respondentsin60small-scale enterprises locatedindifferentpartsofthecountry(20small-scale enterprises locatedinLagosState,20inAnambraStateand20in Kano StateofNigeriarespectively).Dataanalysiswascarriedout using tablesandpercentagesandthenullhypothesesofthestudy wastestedusingchi-square(X2) inferentialstatisticalmodelat5% level ofsignificance. The findings revealedthatthereisasig- nificant relationshipbetweentheoperationofsmallandmedium- scale enterprisesandeconomicgrowthindevelopingnations

Derangement of hemopoiesis and hematological indices in Khat (Catha edulis) - treated rats

The purpose of this study was to identify the sub-acute toxic effects of Khat (Catha edulis) on hemopoiesis and hematological indices of white albino rats. Two groups, each of 10 rats, were used. In the experimental group, a hydro-ethanol extract of C. edulis was administered orally to rats, daily, in single doses of 500 mg/kg body weight, for for weeks. The control group received equivalent amounts of normal saline. Our results show, for the first time, that oral administration of C. edulis hydro-ethanol extract caused significant derangement in hemopoiesis and in gross hematological indices in rats, characterized by macrocytic anemia and leucopenia. Our data show statistically significant decreases in total leukocytes count (TLC) in which, hemoglobin concentration (Hb. conc.), packed cell volume (PCV), and red cell count (RCC), accompanied by significant increases in mean cell volume (MCV), red blood cell distribution width (RDW) and platelets count with no change in mean hemoglobin concentration (MHC). In peripheral blood smears (PBS) of treated rats, there were evidences of dyserythropoiesis- impaired hemoglobinization, macrocytosis, poikilocytosis and anisocytosis, and dysgranulopoiesis- giant forms, hypersegmented neutrophils and bizarre nuclear shapes. In conclusion, our results indicate that oral administration of a hydro-ethanol extract of C. edulis adversely affected blood cell formation and induced macrocytic anemia and leukopenia in rats. However, the exact mechanisms of these hematological changes produced by Khat are still in need for further studies.Keywords:Catha edulis, hemopoiesis, anemia, leukopenia, ratsAfrican Journal of Biotechnology, Vol. 13(2), pp. 349-355, 8 January, 201

Role of thyroid hormones in early postnatal development of skeletal muscle and its implications for undernutrition

Published online by Cambridge University Press 09 Mar 2007Energy intake profoundly influences many endocrine axes which in turn play a central role in development. The specific influence of a short period of mild hypothyroidism, similar to that induced by undernutrition, in regulating muscle development has been assessed in a large mammal during early postnatal life. Hypothyroidism was induced by providing methimazole and iopanoic acid in the feed of piglets between 4 and 14 d of age, and controls were pair-fed to the energy intake of their hypothyroid littermates. Thyroid status was evaluated, and myofibre differentiation and cation pump concentrations were then assessed in the following functionally distinct muscles: longissimus dorsi (l. dorsi), soleus and rhomboideus. Reductions in plasma concentrations of thyroxine (T4; 32%, P < O·Ol), triiodothyronine (T3;48%, P < 0·001), free T3, (58%, P < 0·001)and hepatic 5'-monodeiodinase (EC 1.11.1.8) activity (74%, P < 0·001) occurred with treatment. Small, although significant, increases in the proportion of type I slow-twitch oxidative fibres occurred with mild hypothyroidism, in l. dorsi (2%, P < 0·01) and soleus(7%, P < 0·01). Nuclear T3-receptor concentration in l. dorsi of hypothyroid animals compared with controls increased by 46% (P < 0·001), a response that may represent a homeostatic mechanism making muscle more sensitive to low levels of circulating thyroid hormones. Nevertheless, Na+, K+-ATPase (EC 3.6.1.37) concentration was reduced by 15–16% in all muscles (l.dorsi P< 0·05,soleus P < 0·001, rhomboideus P < 0·05), and Ca2+-ATPase (EC 3.6.1.38) concentration was significantly reduced in the two slow-twitch muscles: by 22% in rhomboideus (P < 0·001) and 23% in soleus (P < 0·05). It is concluded that during early postnatal development of large mammals a period of mild hypothyroidism, comparable with that found during undernutrition, induces changes in myofibre differentiation and a down-regulation of cation pumps in skeletal muscle. Such changes would result in slowness of movement and muscle weakness, and also reduce ATP hydrolysis with a concomitant improvement in energetic efficiency.A. P. Harrison, D. R. Tivey, T. Clausen, C. Duchamp and M. J. Daunce

MODERATING EFFECT OF ENTREPRENEURIAL ORIENTATION ON ENTREPRENEURIAL COMPETENCIES AND PERFORMANCE OF AGRO-BASED SMEs

The objective of this research was to examine the moderating effect of entrepreneurial orientation on the relationship between entrepreneurial competencies and performance of agro-based SMEs in Nigeria. The study used questionnaires gathered from 230 managers of agro-based firms in Lagos state Nigeria. Data analysis was carried out using hierarchical multiple regression to show relationships between the variables. Findings suggest that entrepreneurial competencies have a direct influence on performance of Agro-based SMEs. More so, the statistical result indicates that innovativeness, proactiveness and autonomy are the three entrepreneurial orientations that moderate the relationship between entrepreneurial competencies and performance of the firms

Acanthus montanus: An experimental evaluation of the antimicrobial, anti-inflammatory and immunological properties of a traditional remedy for furuncles

<p>Abstract</p> <p>Background</p> <p><it>Acanthus montanus </it>(Nees) T. Anderson (Acanthaceae) is a shrub widespread in Africa, the Balkans, Romania, Greece and Eastern Mediterranean. It is used in African traditional medicine for the treatment of urogenital infections, urethral pain, endometritis, urinary disease, cystitis, leucorrhoea, aches and pains. In southeastern Nigeria, the root is popular and acclaimed highly effective in the treatment of furuncles. This study was undertaken to experimentally evaluate the antimicrobial and anti-inflammatory properties of the root extract as well as its effect on phagocytosis and specific cell-mediated immune response which may underlie the usefulness of the roots in treatment of furuncles.</p> <p>Methods</p> <p>The aqueous root extract (obtained by hot water maceration of the root powder) was studied for effects on the growth of clinically isolated strains of <it>Pseudomonas aeruginosa </it>and <it>Staphylococcus aureus</it>. The anti-inflammatory activity was investigated using acute topical edema of the mouse ear induced by xylene, acute paw edema induced by agar in rats, formaldehyde arthritis in rats, vascular permeability induced by acetic acid in mice and heat- and hypotonicity-induced haemolysis of ox red blood cells (RBCs). Also evaluated were the effects on <it>in vivo </it>leukocyte migration induced by agar, phagocytic activity of macrophages on <it>Candida albicans </it>and specific cell-mediated immune responses (delayed type hypersensitivity reaction (DTHR) induced by sheep red blood cell (SRBC)). The acute toxicity and lethality (LD₅₀) in mice and phytochemical constituents of the extract were also determined.</p> <p>Results</p> <p>The extract moderately inhibited the growth of the test organisms and significantly (<it>P </it>< 0.05) inhibited (57%) topical acute edema in the mouse ear. It significantly (<it>P </it>< 0.05) suppressed the development of acute edema of the rat paw in a non-dose-related manner and was not effective in inhibiting the global edematous response to formaldehyde arthritis. It also inhibited vascular permeability induced by acetic acid in mice and the haemolysis of ox RBCs induced by heat- and hypotonicity. The extract increased total leukocyte and neutrophil counts and caused a significant (<it>P </it>< 0.05) dose-related increase in the total number of macrophages at the 800 mg/kg dose. On phagocytic activity, the extract evoked a significant (<it>P </it>< 0.05) increase in the number of macrophages with ingested <it>C. albicans </it>at 800 mg/kg dose, and significantly (<it>P </it>< 0.05) inhibited DTHR in a dose-related manner. Phytochemical tests on the extract revealed an abundant presence of alkaloids and carbohydrates while saponins, glycosides, and terpenoids occurred in trace amounts. Acute toxicity test established an oral and intraperitoneal LD₅₀greater than 5,000 mg/kg.</p> <p>Conclusion</p> <p>The effectiveness of the root of <it>A. montanus </it>in the treatment of furuncles may largely derive from mobilization of leukocytes to the site of the infection and activation of phagocytic activity as well as suppression of exacerbated immune responses by its constituents. Antimicrobial and anti-inflammatory activities are likely contributory mechanisms. Phytochemical constituents such as alkaloids and carbohydrates may be responsible for these pharmacological activities.</p

Optimization o f Power Control i n Mobile Multimedia Communication Systems in Hospitals using Genetic Algori thm

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INVESTIGATION OF THE OPTIMUM DISSOLUTION TEMPERATURES OF PHOSPHORUS IN SULPHURIC, NITRIC AND OXALIC ACID SOLUTIONS DURING LEACHING OF IRON OXIDE ORE

Studies were carried out to determine the optimum dissolution temperatures of phosphorus in oxalic, nitric and sulphuric acid solutions during leaching of iron oxide ore. Phosphorus dissolution rates and dissolution per unit rise in temperature were determined and compared to ascertain the preferred acid in terms of effective dephosphorization of iron oxide ore using leaching process. The results of the investigation show that the optimum dissolution temperatures of phosphorus in these acids were found to be 45, 55 and 70ºC respectively. Phosphorus dissolutions per unit rise in temperature in these acid solutions during the increasing and decreasing stage of dissolution were 9.4 and -3.07 mg/kg/ºC 2.88 and -4.7 mg/kg/ºC and also 2.16 and -7.95 mg/kg/ºC respectively. Phosphorus dissolution rates in these acid solutions during the increasing and decreasing stage of dissolution were also determined as 0.67 and -0.13 mg/kg/s, 0.14 and -0.19 mg/kg/s and also 0.1 and 0.44 mg/kg/s for oxalic, nitric and sulphuric acid solutions respectively. This confers to oxalic acid a better dissolution power on phosphorus over nitric and sulphuric acid, followed by nitric acid