One Step Continuous Hybrid Block Method for the Solution of y'''=f(x,y,y',y'')

In this paper, we present a block method for the direct solution of third order initial value problems of ordinary differential equations. Collocation and interpolation approach was adopted to generate a continuous linear multistep method which was then solved for the independent solution to give a continuous block method. We evaluated the result at selected grid points to give a discrete block which eventually gave simultaneous solutions at both grid and off grid points.  The one-step block method is consistent and A -stable, with good region of absolute stability. Experimental results confirmed the superiority of the new scheme over an existing method. Keywords: consistent, convergent, collocation, hybrid points, independent solution, interpolation, zero stabl

Sugar syrup as substitute for nectar: Effect on production and density of the honey bee Apis mellifera Adansonii (Hymenoptera: Apiidae) in artificial beehive

The effect of sugar syrup on colonies of Apis mellifera Adansonii (Hymenoptera: Apidae), in an apiary at University of Lagos, was studied and the colonies were monitored between Nov. 2001 and Oct. 2003. During this period, sugar syrup was administered as nectar substitute to Colonies A and B colonies C and D which lacked sugar syrup served as controls. In the 1st dry season (Nov.2001 – Apr. 2002), the production of colonies A and B were 35.0 kg and 30.5 kg and their population densities were 24,610 and 22,727 respectively, while the production of colonies C and D were 37.0 kg and 40.5 kg and the population densities were 27,040 and 29,790 respectively. In the 1st wet season (May 2002–Oct. 2002), colonies A and B weighed 24.5 kg and 22.5 kg, respectively, while their population densities were 25,360 and 23,810 respectively, Colonies C and D weighed 22.5 kg and 24.0 kg and their population densities were 15,846 and 22,500, respectively. Colonies A and B weighed 42.5 kg and 39.0 kg and had population density of 34,770 and 33,240 respectively in the 2nd dry season (Nov. 2002) – Apr. 2003). Colonies C and D had comparatively lower production (29.5 kg and 35.5 kg) and population densities (25,592 and 31,634 respectively). This study showed that administration of sugar syrup to colonies of A. mellifera Adansonii in wet season sustained more population of bees for foraging activities in the 2nd dry season. This significantly increases population and production in colonies A and B in the 2nd dry season

Studies on the life cycle and morphometrics of honeybees, Apis Mellifera adansonii (Hymenoptera: Apidae) in a Mangrove Area of Lagos, Nigeria

The life cycle of the honeybee, Apis mellifera adansonii, was studied in mangrove area by monitoring the developmental stages and morphology of the castes. It was observed that the fate of the eggs were predetermined at the onset leading to drones, queens or workers. It was also established that the three different castes (drone, queen and worker) exhibit similar patterns of complete metamorphoses. The mean developmental period of the drone from egg to adult stage was the longest (24.97±1.77 days, n = 60) followed by that of worker (20.22 ± 2.20 days, n = 60) and the queen (15.5 ± 2.08 days, n = 60) in that order. The body length and head capsule width varied within the different castes. The general pattern of the studied life cycle of A.mellifera adansonii in Mangrove area of Lagos is similar to A. mellifera scutellata and Africanized A. mellifera studied in other regions. It was concluded that the knowledge of the life cycle of A. mellifera adansonii by bee farmers in their locality may enhance their apicultural practices for better productivity

Quality evaluation of some honey samples from Lagos Nigeria

The quality of five samples of honey obtained from research bee farm (University of Lagos) and Tejuoso market, Lagos, was evaluated. 80 % of the samples exhibited proper maturity based on the low moisture content (17.20 + 0.43 %). The ash contents were within the limit allowed for floral honey (0.6%) and indicating the cleanliness of honey samples. Low hydroxymethylfurfural content (8.49 + 2.67 mg kg-l) and high diastase activity (18.62 + 3.83Go) indicated high level of freshness. The total acidity which was below 40 meq kg-l indicated absence of undesirable fermentation, while the pH (3.87 + 0.20) was within the recommended value. The Glucose, fructose and sucrose contents were 26.80 + 3.96 %, 38.88 + 0.83% and 1.59 + 0.63% respectively

Structural and Optical Properties of Tin Doped Zinc Oxide Fibres Prepared By Electrospinning Technique

The study synthesized ZnO fibers using electrospinning technique. It also characterized and determined the effects of Sn2+ dopant on the optical properties of the fibers synthesized. This was with a view to exploring the potential of improving the performance ZnO semiconductor material in industrial applications. Polyvinyl Alcohol (PVA) solution was prepared and mixed with ZnO source. Zinc acetate was used as the ZnO source while Tin Acetate was used as Sn2+ dopant source. Viscous electrospinning solutions of PVA/Zinc Acetate and three different compositions of Tin Acetate were prepared. The compositions of dopants used were 5, 7 and 9-wt. %. Samples of the depositions from the electrospinning process were annealed at 600o C at a rate of 4o C per minute for 6 hours. Scanning electron microscopy (SEM) was employed to reveal the morphology of the depositions. The structural analysis of the fibers was carried out using x-ray diffractometry (XRD) while the optical properties of the fibers were investigated using ultra violet visible spectrophotometry. The SEM results showed the depositions to be web of fibers. The XRD confirmed the crystallization of undoped and doped ZnO fibers from the acetates. The crystal sizes of the fibers were in the range of 5.566 to 7.202 nm. Furthermore, wide bandgap energy values ranging from 3.26 to 3.46 eV were obtained from the results of the optical properties of the fibers. The results showed that the average crystal sizes of Sn2+ doped ZnO fibers were larger than those of the undoped fibers. However, it was observed that the average crystal size decreases with increase in Sn2+ content. The results also showed that the bandgap energy values of the fibers increase with dopant concentration. The study established the viability of fabricating doped and undoped ZnO structure in form of fibers in order to enhance its performance in industrial applications. Also, the results showed that the optical properties of the fibers improved with increase in Sn2+ dopant concentration. Keywords: ZnO fibers; Electrospinning technique; Structural analysis; Optical properties;  Sn2+ Dopant; Band gap energy value; Crystal siz

Salmonella Typhimurium as a potential anticancer agent: A Review

Bacteria mediated cancer therapy has not been used as much as other methods, despite being considered a potential adjunct in anticancer therapeutic strategy for decades. However, in recent years, there has been considerable interest in exploration of the option of bacteria mediated cancer immunotherapy. The conventional anticancer therapy does not eradicate cancer completely. It often fails and has several other limitations which can easily be overcome through the bacteria mediated approach as an adjunctive therapy. Members of the genus Salmonella have the ability to colonize all forms of tumours and their metastasis much more efficiently than other bacteria. Salmonella has over 2500 serovars of which Salmonella Typhimurium, a non-typhoidal strain, is the most extensively studied for its anticancer activity. S. Typhimurium has the intrinsic attribute of being able to selectively colonize solid tumours and their metastasis. S. Typhimurium is able to target and destroy tumours in three specific ways; inducing immune response to the presence of tumours, utilizing bacterial toxins to directly activate caspase-3, ( an important enzyme of the apoptotic pathway) and also as a vector in delivering of anti-cancer compounds to tumour sites. S. Typhimurium is currently considered as a bacterium with great potential in the field of cancer immunotherapy. In this review, the explanation of the mechanisms of anticancer activity of live attenuated and engineered S.  Typhimurium strains in vitro and in vivo is attempted.</p

Influence of storage conditions and packaging materials on some quality attributes of water yam flour

The study investigated some quality attributes of water yam flour stored in three packaging materials [high and low density polyethylene and plastic container] under different storage conditions [relative humidity (36%, 56%, 75% and 96%), temperature (25±2, 35±2 and 45±2 °C)] for 24 weeks. The functional properties, proximate composition and microbial load of the samples were evaluated at 4 weeks interval. Significant differences (p<0.01) were observed for proximate composition, functional properties and microbial load of the samples during storage. The interactive effect of storage conditions and packaging materials was significant (p<0.01) on proximate composition and pasting properties (except trough viscosity). The yam flour samples were still shelf stable after the 24 weeks of storage

Computation of Gamma Buildup Factors and Heavy Ions Penetrating Depths in Clay Composite Materials Using Phy-X/PSD, EXABCal and SRIM Codes

Most investigations of the gamma-shielding abilities of materials are often based on the Beer-Lambert law including recent studies on clay-polyethylene composites. The findings are usually silent on the secondary radiation effects that commonly occur due to photon buildup, known as Energy Absorption Buildup Factor (EABF) and Exposure Buildup Factor (EBF). In this work, the computation of EABF and EBF in the region of energy 0.015&ndash;15 MeV at different penetration depths or mean free paths up to 40 mfp&mdash;and simulation of 100 keV of Cs and Sr ion-penetration profiles of clay&ndash;polyethylene composites (A&ndash;G) containing 0&ndash;30 wt% low density polyethylene (LPDE)&mdash;was carried out. The buildup factors computation was performed using Phy-X/PSD and EXABCal codes, and the ion-penetrating profile was studied using a Monte Carlo simulation code called Stopping and Range of Ions in Matter (SRIM). The EABF and EBF values are functions of the photon energy and the penetration depth. In the region of intermediate energy, the EABF and EBF values are higher for each of the samples. For a given mfp, the peak value of either EBF or EABF of each sample increases with LDPE wt% in the clay matrix. The projected range of both Cs and Sr ions in the samples decreased with increasing sample bulk densities, with Cs having a higher projected range than Sr in all the samples. The Cs and Sr ions have the lowest respective projected ranges in sample A (of bulk density 2.03 g&middot;cm&minus;3; 0 wt% of LDPE), while the highest projected ranges were recorded in sample G (of bulk density 1.34 g&middot;cm&minus;3; with 30 wt% of LDPE), respectively. This study reaffirmed the suitability of clay composite for gamma-ray shielding applications; however, it may not yet be ready to be used as a backfill material to mitigate the migration of fission products present in radioactive nuclear wastes

Study of Surface Modification of Electrospun Polyethylene Oxide Composite Fibre

Functionalization of polymers had gained attention because of advance applications as sensor, energy devices, membrane, etc. This present study is aimed at studying surface modification as a result of electrospinning functionalized polyethylene oxide (PEO) with zinc ion Zinc chloride was added in various proportions to PEO solution then electrospun at various voltage. Fibres resulted into various shapes; belt, rod, mat and thread which differs from the primary PEO. The mechanism for the morphology modification was studied and the optimum conditions which retain the fibrous morphology were noted. This functionalized PEO can be used as energy device. Keyword: Polyethylene oxide, Modification, Fibre, Composite, Functionalize