Effects of Mucilage on the Pasting, Thermal and Retrogradative Properties of Native and Modified Starches Obtained from Ipomoea Batatas

This study investigates the effect of mucilage on the pasting, thermal and retrogradative properties of native, pregelatinized and acid modified starches obtained from ipomoea batatas. Dispersions of mucilage with each starch was carried out in a ratio 1:20, 1:10, 1:5, 3:10 and 2:5 respectively. Native starch (SPS) had a higher peak viscosity, trough, breakdown, final viscosity and enthalpy (?H) as compared to pregelatinized starch (PPS) and acid modified starch (APS) in the order SPS > PPS > APS. Parameters such as pasting temperature, syneresis, onset, peak and conclusion temperature were in the order APS > PPS > SPS. Pregelatinized starch had a higher set back and peak time as compared to other starches in the order PPS > SPS > APS. Generally, dispersions of SPS, PPS and APS in mucilage followed similar trends as described above with increase in peak time, pasting temperature and ?H as the mucilage concentrations increased and a decrease in peak viscosity, trough, breakdown, final viscosity, set back, syneresis (except SPS), onset, peak and conclusion (except APS) temperature as the mucilage concentration increases. Keywords: Ipomoea batatas starch, pregelatinized, acid modified, dispersion, mucilag

Composition and Physicochemical Properties of Starch from Christ Thorn Seeds

Starch was extracted from seeds of Christ Thorn by hot water extraction method. The composition and physicochemical properties of the extracted starch were determined using standard methods. The results obtained from the analyses revealed that the % yield of starch was 43.2%, while moisture content, ash content, starch protein and starch lipid were 7.8%, 0.01%, 0.12% and 0.32% respectively. The results also showed amylose content of 24.6%; swelling power of 37.5g/g, solubility of 2.1%, amylose leaching of 3.7% and gelatinization temperature of 68oC. From the results, the paper concludes that with minor modifications, the seeds can be used as alternative sources of starch for industrial products

THE EFFECT OF DRYING TECHNIQUES ON THE ELASTOPLASTIC PROPERTIES OF LOCALLY PROCESSED MICROCRYSTALLINE CELLULOSE

The study investigated the effect of three different drying techniques i.e. microwave, sun and oven drying on the physicochemical and compressional characteristics of microcrystalline cellulose obtained from sawdust, an agricultural waste product. The physicochemical properties were investigated by assessing the tapped and bulk densities, flow properties i.e. angle of repose, flow rate, compressibility index and Hausner's ratio, while the compressional properties were evaluated using both the Heckel and Kawakita equations. The results obtained showed that the values obtained for angle of repose was in the order of micro< sun< oven while the order for flow rate was the reverse of the angle of repose ratio and it was in the order; sun<oven<micro. The compressional characteristics showed that the order of P values i.e plastic deformation at onset of compression y of the microcrystalline cellulose powder was in the order of micro<oven<sun, while the order of P value i.e. k plastic deformation during compression was micro<sun<oven. The study concluded that microwave drying method would lead to production of microcrystalline cellulose with enhanced physicochemical and compressional properties

Toxicity Studies on Aqueous-Methanol Pod Extract of Vigna unguiculata (Cowpea) in Wistar Strain Albino Rats

Herbal preparation of Vigna unguiculata (cowpea) pod has long been used by a group of Hausa people from northern Nigeria called Yan tauri performers and traditional healers. This study was conducted to evaluate the toxicological effect of the extract in Wistar strain albino rats using biochemical, haematological and histopathological indices of toxicity. Acute toxicity (LD50) and sub-chronic toxicity studies were determined using the method developed by OECD. Twenty-five (25) rats were grouped into five(5) consisting of five(5) rats each, one of the groups served as control., Group II, III, IV and V were orally administered with the extract at a daily dose of 400 mg/kg, 800 mg/kg, 1200 mg/kg and 1600 mg/kg of the extract, respectively for 28 days. The LD50 of the extract was greater than 5000 mg/kg and its oral administration for 28 days did not produce significant changes (P˃0.05) on biochemical and haematological indices.  Histopathological evaluation revealed mild widening of Bowman’s capsule of animals administered with 1200 mg/kg and 1600 mg/kg of the extract. It can thus be concluded that the pod is non-toxic. Keywords: Vigna unguiculata pod, Yan tauri performers, Aqueous-methanol extract, Acute and subchronic toxicit

Investigation of the Performance of Site Diversity through Rain Gauge Measurements in South-South Nigeria

Site diversity is an effective technique to mitigate rain attenuation, especially in regions where rainfall rates are high. The South-South region of Nigeria is characterized by the tropical rain forest climate, exhibiting high rainfall rates almost all year round. This paper  investigates the performance of site diversity technique  in the South-South Nigeria at Ka-band frequency of 20 GHz. Rainfall data obtained from the Nigerian Meteorological Agency (NIMET) over a period of five years (2010 to 2014) were analysed to derive the one-minute rainfall rate distribution for four selected earth stations (University of Uyo, Uyo; Akwa Ibom International Airport, Uyo; Margaret Ekpo International Airport, Calabar; and Port Harcourt International Airport, Port Harcourt) within the South-South Nigeria. The link parameters of NigComSat-1R were used with the ITU-R model for rain attenuation to estimate the rain attenuation distribution through an annual cumulative distribution and percentage of outage time between 0.01 to 100 %. Site diversity (SD) was implemented, taking University of Uyo as the reference site. The results obtained shows that the SD gain between the University of Uyo and Port Harcourt International Airport is higher than the SD gain recorded between University of Uyo and Margaret Ekpo International Airport. This is consistent with the fact that longer distances between the earth stations yield higher SD gain

Investigation of the Performance of Site Diversity through Rain Gauge Measurements in South-South Nigeria

Site diversity is an effective technique to mitigate rain attenuation, especially in regions where rainfall rates are high. The South-South region of Nigeria is characterized by the tropical rain forest climate, exhibiting high rainfall rates almost all year round. This paper  investigates the performance of site diversity technique  in the South-South Nigeria at Ka-band frequency of 20 GHz. Rainfall data obtained from the Nigerian Meteorological Agency (NIMET) over a period of five years (2010 to 2014) were analysed to derive the one-minute rainfall rate distribution for four selected earth stations (University of Uyo, Uyo; Akwa Ibom International Airport, Uyo; Margaret Ekpo International Airport, Calabar; and Port Harcourt International Airport, Port Harcourt) within the South-South Nigeria. The link parameters of NigComSat-1R were used with the ITU-R model for rain attenuation to estimate the rain attenuation distribution through an annual cumulative distribution and percentage of outage time between 0.01 to 100 %. Site diversity (SD) was implemented, taking University of Uyo as the reference site. The results obtained shows that the SD gain between the University of Uyo and Port Harcourt International Airport is higher than the SD gain recorded between University of Uyo and Margaret Ekpo International Airport. This is consistent with the fact that longer distances between the earth stations yield higher SD gain

Knowledge, attitude and practice towards epilepsy among secondary school students in Enugu, South East Nigeria

AbstractPurposeThe purpose of this study was to determine the knowledge and attitude of secondary school students to epilepsy and its treatment that could pose as barriers in the treatment and care of epilepsy patients within the community.MethodsThis study was cross-sectional and descriptive in design using a self administered custom designed multiple choice questionnaire with sections on general information on epilepsy, awareness and perception of epilepsy, treatment of epilepsy/seizures and attitude towards people living with epilepsy.ResultsOut of 969 questionnaires analyzed, the majority of the students (87.6%) had heard of epilepsy as a disease. The commonest sources of information were the electronic media (36.4%) and family members (25.6%). More than half (59.4%) had witnessed a convulsion in the past and 8.9% had a family member with epilepsy. Jerking (50.6%) and loss of consciousness (47.4%) were identified as the commonest manifestations of epilepsy. Epilepsy was considered a psychiatric disorder by 51.9% and as an infectious disease by 40.6%. About 39.3% considered epilepsy to be due to spiritual causes, old age or poisoning/bad blood. A total of 63.1% regarded orthodox medicine and prayers as the best means to treat epilepsy, while 6.8% chose herbal remedies. Concerning first aid treatment, 50.6% agreed that an object should be inserted into the mouth, while 49.5% would call for medical help and 28.8% would remove the person from harm. On attitude, 64.9% would not keep a friend with epilepsy, 69.1% would not play with someone with epilepsy, 84.2% would not marry someone with epilepsy. 41.1% of the students said that people with epilepsy should neither marry while 42.2% say they should not have children. Only 39.1.5% had an overall positive attitude towards people living with epilepsy.ConclusionsThere is a persisting poor knowledge, attitude and practice of epilepsy among secondary school students in SE Nigeria. Efforts should be made to include basic facts about disorders with social consequences such as epilepsy in school health education curriculum

Classroom Interaction Practices and Students’ Learning Outcomes in Physics: Implication for Teaching-Skill Development for Physics Teachers

In the last decade, evidence in the science education literature seems to suggest that student-centered classroom interaction appears to have effect over and above teacher-centered interaction in enhancing learning outcomes in various science subjects especially in Physics. Based on this premise, this paper examined the effects of teacher-centered and student-centered interaction practices on students’ achievement and attitude in dynamics, an aspect of Physics considered abstract at the secondary school level. This study employed both the quasi-experimental and observational survey designs. From a sample of four comparable schools in Kogi East Local Government Areas of Kogi State, Nigeria, 139 physics students from intact classes and seven teachers (4 who did the teaching and 3 others who observed in all classes) were involved in the study. Three instruments developed were used for data collection. These are Teacher-Student Classroom Observation Schedule (TSCOS), Students’ Attitude Questionnaire (SAQ), and Physics Achievement Test (PAT) with reliability indices of 0.68, 0.86 and 0.79 respectively. The data generated from the use of the instruments were analyzed using descriptive statistics of mean and standard deviation to answer the research questions, while the ANCOVA statistic was used to test the hypotheses at 0.05 α-level. Results revealed that the difference between the mean performances and mean attitude of students exposed to the two types of interactions were statistically significant. Gender differences in mean performance and attitude scores were not significant. It was recommended that student-centered classroom interaction strategy should be advocated for use. Implications were drawn for teacher skills acquisition

Correction to: Cluster identification, selection, and description in Cluster randomized crossover trials: the PREP-IT trials

An amendment to this paper has been published and can be accessed via the original article