The Effects of Problem-Solving Instructional Strategy, Three Modes of Instruction and Gender on Learning Outcomes in Chemistry

This study was designed to investigate the effects of problem-solving instructional strategy, three accompanying modes of instruction (i.e. Remediation, Feedback and Practice) and gender on learning outcomes in chemistry. A pre-test post-test control group quasi experimental design was adopted for the study. Data were collected from a sample of 210 SS2 Chemistry Students made up of 109 males and 101 females selected from six schools in three (3) Local Government Areas of Ekiti State, Nigeria based on multi-stage random sampling techniques. The Seven Step Chemistry Problem-Solving Model as suggested by Frazer (1981) and Selvarantnam (1983) was adopted for the study. The experiment was carried out on four (4) groups of Students. The Students in experimental groups 1 and 2 were exposed to Problem-Solving approach coupled with remediation and feedback respectively, experimental group 3 was exposed to Problem-Solving coupled with practice. The fourth group not treated formed the control group. Analysis of Covariance (ANCOVA) was used to analyse the data with the pre-test scores as covariates. The findings revealed that students in experimental group 1 (i.e. Problem-Solving coupled with remediation) had the highest performance in Chemistry Achievement Test (CAT) followed by those exposed in experimental group 2 and 3 respectively (i.e. Problem-Solving coupled with feedback and practice respectively).However, the control group had the least performance in Chemistry Achievement Test (CAT). The implications were discussed and recommendations given. Keywords: Effects of Problem-Solving, Modes of Instruction, Learning Outcomes

Effects of Out-door Activities on Students’ Attitude towards Physics in Secondary Schools

The study investigated the effects of out-door activities on students’ attitude towards learning of Physics in Senior Secondary School Physics in Ekiti State, Nigeria. The research design adopted in the study was Pretest-Posttest Quasi-experimental. The sample for the study was 150 Senior Secondary One (SSI) Physics students (this sample was divided into the experimental and control groups in ratio 1: 1 i.e. 75 in each group), selected through the multistage sampling technique from a total population of 7,852 SS I students offering Physics in all the 184 public Senior Secondary Schools in Ekiti State. The instrument used to collect relevant data from the subjects was Physics Attitudinal Scale (PAS). The reliability of the instrument was determined through the split-half method with the reliability coefficient of 0.83. Two null hypotheses were tested at 0.05 level of significance. The data collected were analysed using inferential statistics of t-test and Analysis of Covariance (ANCOVA). The results of the analyses showed that there was significant difference in the attitude of students to Physics in the experimental and control groups in favour of experimental group. Based on the findings of the study, it was recommended that non-conventional teaching approaches such as using out-door activities, should be introduced into the teaching of Physics in the nation’s secondary schools to reinforce the hitherto adopted conventional teaching method and Physics teachers should be encouraged to make use of these new teaching approaches

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Bioavailability of Cu, Zn and Mn from Mineral Chelates or Blends of Inorganic Salts in Growing Turkeys Fed with Supplemental Riboflavin and/or Pyridoxine

n 84-day feeding trial was conducted in growing turkeys to measure the bioavailability of Cu, Zn and Mn from a commercial mineral chelate and corresponding inorganic salts in composite feeds containing supplemental riboflavin (B2) and/or pyridoxine (B6). A total of 320, 28-day-old British United Turkeys (BUT) were assigned to eight dietary treatments in a 2 × 4 factorial arrangement comprising two trace mineral sources: chelated trace mineral blend (CTMB) and its corresponding inorganic trace minerals blend (ITMB) fed solely or with supplements of vitamin B2 (8 ppm) or B6 (7 ppm) or 8 ppm B2 + 7 ppm B6. Each treatment was replicated four times with 10 turkeys each. It was observed that turkeys fed with diets supplemented solely with ITMB elicited higher (P < 0.05) Zn excretion than their counterparts fed with diets containing ITMB with supplements of vitamins B2 and/or B6. Manganese retention was lower (P < 0.05) in turkeys fed with diets supplemented solely with ITMB than those fed with diets containing vitamins B2 and/or B6 additives. Combination of CTMB or ITMB with B6 improved (P < 0.05) the concentration of Mn in the liver and Cu in the bone. It was concluded that the minerals in CTMB were more available to the animals than ITMB. Furthermore, vitamins B2 and/or B6 supplementation improved the bioavailability of the inorganic Cu, Zn and Mn in growing turkeys and tended to reduce the concentration of these trace elements in birds' excreta