Teachers’ views on challenges affecting learners’ performance in natural science

In Namibia, natural science (NS) is one of the priority subjects in upper primary phases (Grades 4 to 7). However, in the Omusati Region of Namibia, there are increasing public concerns that many learners are not performing well in NS. Thus, this study surveyed the views of NS teachers on the challenges affecting upper primary learners’ performance in NS at three selected combined schools in the Omusati Region. Qualitative research design using face-to-face interview was used to gather the views of upper primary NS teachers in the schools. Seven teachers who are currently teaching NS at the selected schools were selected using the purposive sampling method to participate in the study. The results obtained revealed that the following challenges affect upper primary learners’ performance in NS in the selected schools: medium of instruction, lack of adequate teaching and learning resources, lack of laboratories, sensitive topics, overcrowded classroom, indiscipline among learners, absenteeism, unfavorable teaching environment, hunger, and lack of proper guidance from subject advisory teachers. The study recommended that the government should provide schools with feeding programs, build laboratories, renovate classes and provide teaching materials. The schools should evolve disciplinary measures to check the learners’ indiscipline

The role of biotechnology in ensuring food security and sustainable agriculture

Food security and sustainable agriculture have become a burning issues in the national discuss at all levels of government as plans are being made for a changing global climate and increasing global population. One of the most important environmental challenges facing the developing world is how to meet current food needs without undermining the ability of future generations to meet theirs. Agricultural production must be sufficient to feed us now and in the future. Evidently, the current state of agricultural technology will not suffice to meet the production challenges ahead. Innovative technologies have to be exploited in order to enable sufficient food availability in the future. In the current practice of modern agriculture which relies on high inputs such as fuel-powered tractors, chemical fertilizers and chemical pesticides, deploying a smart mix of farming techniques using genetic engineering of biotechnology and integrating same into the traditional smallholders farming systemoffer a bright prospect of meeting the growing demand for food by improving both yield and nutritional quality of crops and reducing the impact on the environment.Keywords: Biotechnology, food security, sustainable agriculture, developing countries, technology integration, population growt

Computational Model of Artificial Neural Networks and its Applications in Data Mining

Data remain a very important ingredient required by any organization to make informed decision as it affects operations. Companies have been collecting data from various sources over the decades bringing about a very large volume of data warehouse. Unfortunately, most organizations build databases which are redundant and never used for any meaningful thing. While few companies use the data collected in their databases when taking strategic decisions others barely do same. However, for an organization to immensely derive benefits from the massive data warehouse, there is the need for an effective and efficient means of analysing the data with a view to extracting meaningful knowledge that is sufficient to achieve organizational goal. To achieve this, Artificial Neural Network (ANN) technique through the concept known as data mining is presented. The paper reviewed artificial neural network technique for data mining, examines the computational model behind this technique and analysed its use and application as a predicting or forecasting tool. Results shows that ANN’ has capability in data management, analysis and able to provide desirable knowledge for management decision making processes. It is therefore recommended that data mining tools like ANN and others be applied to organization’s databases which hitherto have not been minned in order to provide management with intelligence for decision makin

Monetary Policy and Commercial Banks’ Performance in Nigeria

The study was carried out to examine the impact of monetary policy on commercial banks’ performance in Nigeria in a micro-panel analysis. Interest rate and money supply were used as proxies for monetary policy, while profit before tax (PBT) was used to represent commercial banks’ performance. Pooled regression, Fixed effect regression, and random effect regression were all carried out in the analysis. However, Hausman test revealed that fixed effect regression is the most appropriate. The results show that there is a positive relationship between banks’ profits and monetary policies as proxied by money supply and interest rate. However, interest rate was not statistically significant at 1% and 5% levels. This study therefore recommends that interest rate policy should be looked into by the monetary authority in a way that is friendly to loan advancement in the country. Key words: Monetary Policy, Fixed effect, Hausman test, Banks’ Profits, Nigeri

Determination Of Heavy Metals In Brewer’s Spent Grains Obtained From Benue Brewery Limited (BBL), Makurdi, North Central Nigeria.

The concentration of some heavy metals (Mn, Pb, Cu, Cr, Fe, Zn, Ni and Cd) in spent grains obtained from Benue Brewery Limited, Makurdi North Central was determined using Atomic Absorption Spectrophotometers (AAS). The results show the concentration of the metals as follows: Cr (0.197ppm), Cu (0.185ppm), Cd (0.039ppm), Fe (0.929ppm), Mn (1.235ppm), Ni (0.197ppm), Pb (0.265ppm) and Zn (34.478ppm). Comparison of the concentration of these heavy metals in the spent grains with those of the international/national standards of heavy metals for food, vegetables, cereals and drinking water shows that all but Zn was above allowable limit whereas, the concentrations of other metals analyzed were found to be below the standard maximum permissible limits. This shows that the spent grains are to a certain extent suitable for use as a source of feed formulation for animals and locally made fertilizer for plants. Key words: Spent grains, Heavy metals, Concentration, AAS. Food industry, Benue brewery

Properties of Concrete Produced with Waste Bottle Caps (WBC) as a Partial Replacement of Coarse Aggregate and Orange Leaves Powder as Plasticizer

Green building is an increasingly important global concern and a critical way to conserve natural resources and reduce the amount of materials going to our landfills. Large quantities of metal waste are generated from empty metal cans and bottle caps of juices and soft drinks. This is an environmental issue as metal waste is difficult to biodegrade and involves processes either to recycle or reuse. Today the construction industry is in need of finding effective materials for increasing the strength of concrete structures with low cost, and with less environmental damage. This research is aimed at addressing such issues by investigating the possibility of using waste bottle caps (WBC) to partially substitute for coarse aggregate and using orange leaves powder as plasticizer in concrete production. The slump, demoulded density, split tensile strength, compressive strength, flexural strength properties at different percentages replacement of coarse aggregate with waste bottle caps were investigated in the laboratory. The work shows that compressive strengths of 83.88%, 76.25% and 63.17% of the control (0%) can be achieved at the 28-day by replacing coarse aggregate with 5%, 10% and 15% of the waste bottle caps respectively. The research also indicates that optimum result in terms of compressive strength is between 5% and 15% of gravel replacement given a value of 35.85N/mm2 and 27N/mm2 respectively. Keywords: Landfills, Green building, Compressive strength, Flexural strength, Waste Bottle Caps, Construction industry and Biodegrad

Single ion heat engine with maximum efficiency at maximum power

We propose an experimental scheme to realize a nano heat engine with a single ion. An Otto cycle may be implemented by confining the ion in a linear Paul trap with tapered geometry and coupling it to engineered laser reservoirs. The quantum efficiency at maximum power is analytically determined in various regimes. Moreover, Monte Carlo simulations of the engine are performed that demonstrate its feasibility and its ability to operate at maximum efficiency of 30% under realistic conditions.Comment: 5 pages, 3 figure

Effect of Zone of Proximal Development on the Performance of Learners in Stoichiometry in Selected Secondary Schools in the Zambezi Region, Namibia

This study investigated the effect of the Zone of Proximal Development (ZPD) on the performance of secondary school learners in stoichiometry in three selected schools currently doing Physical Science at Higher and Ordinary levels in the Zambezi Region, Namibia. Structured questionnaires were used to collect information bothering on learners’ knowledge of stoichiometry contents, perceived factors affecting learners’ performance in stoichiometry and strategies for improvingperformance in stoichiometry. A total of 83 participants from four secondary schools were randomly selected to fill the questionnaires. The results obtained showed that only 29.25% of the participants indicated that they have good knowledge of stoichiometry to solve related problems while 55.50% disagreed and 15.25% were undecided. On the perceived factors affecting learners’ performance in stoichiometry, it was found that only 28.25% of the participants indicated that they understand the principles of stoichiometry while majority indicated lack of understanding of the principles such as reactant-reactant pair and reactant-product pair needed to effectively plan solution to stoichiometry problem. There is also lack of peer-assisted learning as indicated by the participants. Peer-assisted learning is a very helpful approach to solving general academic problems as learners could easily discover useful tips through exchanging of ideas. On the strategies for improving performance in stoichiometry, only 13.00% of the participants indicated that they do meet their science teachers for help when solving stoichiometry problems but majority do not and are also not aware of any tutorial class to help week learners in stoichiometry.However, the majority (55.75%) of the participants disagreed with the idea whether stoichiometry should be removed from secondary school syllabus. Considering the challenges learners faced in stoichiometry in the study area and majority are still willing to have it on their syllabus, we recommend that further indepth research be carried out to identify specific challenges responsible for learners’ poor performances in stoichiometry in the study area and devise remediation measures. There is also need to institute proper strategies that will support learners understanding of stoichiometry taught in secondary schools in the region

Strength Properties of Asphalt Mixture Produced with Polyvinyl Chloride (PVC) Modified Bitumen

In recent time, more polyvinyl chloride (PVC) plastic are produced than what is currently being recycled, that contributes to the volume of waste. This occurrence prompted the exploration of polymer modified bitumen (PMB) to address the waste concern and thereby cuts cost in bituminous mix and improves pavement performance. This research evaluated the strength properties of asphalt mixture produced with polyvinyl chloride modified bitumen. Marshall method of mix design was used in the production of hot mix asphalt (HMA). Scanning Electron Microscopy (SEM), Fourier Transform Infra-red (FTIR) and Energy Dispersive X-Ray Spectrometry (EDS), used for microstructural examination and elemental analysis. These materials conform with its physical properties and characteristics. The shredded, grinded plastic revealed high binding properties when blend with bitumen. The percent incorporated was 2 - 10% PVC content and the Optimum Bitumen Content obtained was 10%, at 9.57kN for stability. The modified bitumen for penetration recorded at 68mm, which conformed with 60/70 grade bitumen, softening point recorded at 52oC, ductility was recorded at 107cm, specific gravity at 1.02, flash and fire point at 294oC and 306oC, solubility at 97% respectively. The properties were satisfactorily for grade 60/70 bitumen at 4% PVC by weight and be used as bitumen modifier for heavy traffic condition. Polyvinyl Chloride modified at 8 - 10%, be used at cold climates, while 2, 4, 6% PVC modified be used in warm regions. Therefore, the experiment proved these materials with characteristics, stability and stiffness be used for pavement constructions