The Influence of Environmental Factors on the Students’ Academic Performance In Zanzibar.

This study investigated the influence of school environmental factors on secondary school students’ academic performance in North “A” District, Zanzibar. The research had three objectives namely: to determine the influence of school physical environmental factors on students’ academic performance in secondary schools in North “A” District in Zanzibar, to assess the influence of classroom environment on teaching and learning in secondary schools in North “A” District in Zanzibar, to investigate stakeholders’ opinion on effective ways of improving the influence of school environmental factors in teaching and learning in secondary schools in North “A” District in Zanzibar. This study applied a case study design in which qualitative and quantitative approaches were used. The sample size had a total of 108. The data were collected through questionnaires, interviews, Focused Group Discussion and documentary reviews. Qualitative data were subjected to content analysis while quantitative data were processed to get frequencies and percentages that were used for inferences. The findings reveal that students’ academic performance was influenced by a number of school environmental factors including: teacher-students relationships, availability of instructional resources; students’ English language competency; the quality of classroom management practices; school quality assurance practices; adequacy and quality of teachers accommodation and classroom or instructional facilities. The study recommended that, teachers needed to be provided with continuous in-service trainings so that they could apply the global changing technological environment on students teaching and learning. The need to focus on improving school infrastructures was another major recommendation. Keywords: School, Environmental, Students’ Performance, Zanzibar

Syntheses and Step-by-Step Morphological Analysis of Nano-Copper-Decorated Carbon Long Fibers for Aerospace Structural Applications

Carbon long fiber/copper composites were prepared using electroless and electroplating methods with copper metal for potential aerospace applications. Carbon fibers were heat-treated at 450 °C followed by acid treatment before the metallization processes. Three different methods of metallization processes were applied: electroless silver deposition, electroless copper deposition and electroplating copper deposition. The metallized carbon fibers were subjected to copper deposition via two different routes. The first method was the electroless deposition technique in an alkaline tartrate bath using formaldehyde as a reducing agent of the copper ions from the copper sulphate solution. The second method was conducted by copper electroplating on the chemically treated carbon fibers. The produced carbon fiber/copper composites were extensively investigated by Field-Emission Scanning Electron Microscopy (FE-SEM) supported with an Energy Dispersive X-Ray Analysis (EDAX) unit to analyze the size, surface morphology, and chemical composition of the produced carbon long fiber/copper composites. The results show that the carbon fiber/copper composites prepared using the electroplating method had a coated type surface morphology with good adhesion between the copper coated layer and the surface of the carbon fibers. However, the carbon fiber/copper composites prepared using the electroless deposition had a decorated type morphology. Moreover, it was observed that the metallized carbon fibers using the silver method enhanced the electroless copper coating process with respect to the electroless copper coating process without silver metallization. The electrical conductivity of the carbon fiber/copper composites was improved by metallization of the carbon fibers using silver, as well as by the electrodeposition method

Improved crowd psychological model and control

The behavior of human crowd is an interesting phenomenon in which individuals are set as a collection that comprises of a highly dynamic social group. The crowd behaviors have been investigated by researchers over the years. Recent works include the study in modeling and controlling of the dynamic psychological behavior of crowds such as students’ behavior in a classroom or people’s behavior in a one-dimensional queue. In this paper, an improved version of the psychological crowd model has been proposed, where the social interaction between two individuals in a crowd is represented by a weightage, called the weight of social interaction. It has been shown that the inclusion of the social interaction weight has allowed social interactions between individuals to be included and results in a more accurate representation of the crowd’s psychological factors propagations. Since the psychological dynamics of crowd is naturally unstable, this paper also discusses the application of two nonlinear control approaches to stabilise the crowd to make it calm. Results show that for a crowd of n number of agents, the single-agent controller gives similar performance with the n-agent controller but with much less resources. The simulation results also show that it takes less amount of time to stabilise a crowd when the crowd model includes social interaction weights

Experimental validation of a theoretical model for flexural modulus of elasticity of thin cement composite

Experimental and analytical investigations for the modulus of elasticity of thin cement composite composed of mesh and mortar are demonstrated. Based on the analyses and experimental data, new equations for the modulus of elasticity of thin cement composite are proposed. It is observed that the flexural modulus of elasticity of thin cement composite depends on the elastic modulus of mortar and some factor of the difference of elastic modulus of mesh and mortar. Results obtained by using the proposed equations are compared to those of the available equations. It has been found that the newly developed equations give relatively conservative results as compared to the typically used ones. A comparison between the analytical and experimental findings further indicates that there is a good agreement between the analytical and experimental result

An Analysis of the Prevalence of Pneumonia for Children under 12 Year Old in Tawau General Hospital, Malaysia

Pneumonia is one of the serious illnesses, which involves lung infection specifically alveoli. Nearly 40,000 to 70,000 people die each year in United State because of pneumonia. Therefore, it is not a surprise that pneumonia is one of the most critical illnesses for children under 12 years old in many parts of the world, including Malaysia and particularly in Tawau, Sabah, Malaysia. The objectives of this study are: to develop a summary on the prevalence of pneumonia in Tawau General Hospital, to analyze the best practice to prevent this illness and lastly to determine an overview of which area that is widely affected by pneumonia. The results can assist doctors and the government to take major precautions and preventive measures efficiently to the full extent. This paper presents a descriptive analysis of the data, which are retrieved from the medical reports at the Tawau General Hospital. Through the findings, pneumonia is widely spread among young children under 12 years old. There are more than one major factor that leads to this critical illness, such as family background, genetic and environment. Therefore, the government, doctors and parents should take major steps to prevent children suffering from pneumonia.Comment: Presented at the International Seminar on the Application of Science & Mathematics 201

Development of a quantitative food frequency questionnaire for use among rural South Africans in KwaZulu Natal

Background: South Africa is experiencing a dietary and lifestyle transition as well as increased rates of noncommunicable chronic diseases. Limited information is available on the diets of rural populations. The present study aimed to characterise the diets of men and women from rural KwaZulu-Natal (KZN) and develop a quantitative food-frequency questionnaire (QFFQ) specific for this population. Methods: A cross-sectional study was carried out by collecting single 24-h dietary recalls from 81 adults and developing a QFFQ in Empangeni, KZN, South Africa. Results: The diet of this population was limited in variety, high in plant-based foods (especially cereals and beans), and low in animal products, vegetables and fruits. Amaize meal staple (Phutu) was consumed by over 80% of subjects and accounted for almost 45% of energy intake, as well as making an important contribution to fat and protein intake. Most of the protein consumed by the study population was plant-based protein, with almost 40% being obtained from the consumption of phutu and beans. A culturally appropriate QFFQ was developed that includes 71 food and drink items, of which 16 are composite dishes unique to this population. Conclusions: Once validated, this QFFQ can be used to monitor diet-disease associations, evaluate nutritional interventions and investigate dietary changes in this population

Antifungal activity of eco-safe nanoemulsions based on Nigella sativa oil against Penicillium verrucosum infecting maize seeds: Biochemical and physiological traits

The main goals of the present investigation were to develop O/W nanoemulsion fungicides based on cold-pressed Nigella sativa (black seed) oil to prevent Penicillium verrucosum infection of maize seeds and to test their antifungal activity against this fungus. Additionally, the effect of these nanoemulsions on plant physiological parameters was also investigated. Two nonionic surfactants namely Tween 20 and Tween 80 were used as emulsifying agents in these formulations. The effect of sonication time and surfactant type on the mean droplet size, polydispersity index (PDI), and zeta potential of the nanoemulsions were determined by dynamic light scattering (DLS). Results indicated that both sonication time and emulsifier type had pronounced effects on the stability of O/W nanoemulsions with a small particle size range (168.6–345.3 nm), acceptable PDI (0.181–0.353), and high zeta potential (−27.24 to –48.82 mV). Tween 20 showed superior stability compared to Tween 80 nanoemulsions. The in vitro results showed that complete inhibition of P. verrucosum-growth was obtained by 10_T80 and 10_T20 nanoemulsions at 100% concentration. All nanoemulsions had increment effects on maize seed germination by 101% in the case of 10_T20 and 10_T80 compared to untreated seeds or the chemical fungicide treatment. Nanoemulsions (10_T20 and 10_T80) were able to stimulate root and shoot length as compared to the fungicide treatment. Seed treatment with 10_T80 nanoemulsion showed the highest AI and protease activity by 75 and 70%, respectively, as compared to the infected control. The produced nanoemulsions might provide an effective protectant coating layer for the stored maize seeds

Anatomy and histochemistry of structures producing aroma in leaves of Sygyzium aromaticum (L.) Merr. and Clausena excavata Burm. f.

Anatomical and histochemical studies on leaves of Syzygium aromaticum and Clausena excavata have been carried out. This study was conducted in order to investigate the relationship between aroma production and a plant's secretory structures. Leaves from the two tropical aromatic plants were sampled from the Institute of Bioscience (IBS) Conservatory Park and transversely sectioned through lamina, midrib and petiole with a sliding microtome for anatomical investigation. Through light microscopy, oil cells and secretory cavities were distributed near the adaxial and abaxial epidermal layers with large in size, up to 60 µm length. Other leaf anatomical characters such as shape of petiole and midrib, pattern of vascular bundle, palisade and spongy mesophyll, the presence or absence of brachysclereids and crystals are also observed. This study also aimed to investigate the leaf's secretory structures responsible for plants' aroma production and to detect the presence of terpenes and essential oil in secretory structures histochemically

Determination of phase wetting in oil-water pipe flows

Oil-water two-phase flow is often a problem in transportation since the corrosion rate is closely related to which phase wets the pipe. The problem has been investigated on a large scale, in a 60 meter-long flow loop with Saudi Arabian crude oils. In this paper extensive experimental studies of flow pattern as well as phase wetting determination have been carried out for different crude oils and different pipe inclinations. Four experimental techniques have been applied to determine which phase, either water or oil, wets the pipe inner wall at different flowing conditions: wall conductance probes, wall sampling, flow visualization, and corrosion monitoring by electric resistance probes. Based on the overlapping information from these techniques, comprehensive phase wetting maps as a function of water cut and flow velocities were obtained. Three flow patterns were observed: stratified flow, stratified flow with mixed layer, and dispersed flows. The comparison of flow pattern and wetting regimes gives good understanding of the water wetting mechanism. Moreover, the phase wetting maps produced are a precious tool which can be used as a useful reference for corrosion engineers and pipeline operators to manipulate oil-water two-phase flow systems under corrosion free conditions

Optimal exit configuration of factory layout for a safer emergency evacuation using crowd simulation model and multi-objective artificial bee colony optimization

This work aims at providing a systematic method in producing a safer and optimal factory layout based on a crowd simulation model and the multi-objective artificial bee colony optimization technique. Apart, from ensuring the efficiency of manufacturing processes in planning a factory layout, it is also important that the safety aspect is taken into account. A factory is usually a closed working area consisting of machines, equipment, assembly lines as well as individual working space and other departments within the factory. In this environment, workers move around in the factory to perform different activities, and hence highly complex crowd behaviours that are influenced by the physical, social and psychological factors of the crowd might take place. Therefore, the layout of the factory must be carefully designed so that efficient movements of people can be obtained. Furthermore, during emergency situations that require efficient evacuation of workers from the factory building, a good factory layout will prevent or minimize the possibility of injuries during the evacuation process. This will reduce the evacuation egress time, which is the quantity used to evaluate the evacuation efficiency and the building's level of safety. One of the techniques to assess the evacuation efficiency of a particular space configuration is by using the crowd simulation model. Recent evidences suggest that the representation of crowd dynamics using a simulation model is useful, where experiments with real humans are too dangerous and not practical to be implemented. This work explains the method to provide optimal exit door configurations for a factory layout by analyzing the crowd evacuation time and the discomfort level, where the proposed optimum exit configurations will be compared with the original configuration for a better evacuation efficiency