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Item Reevaluating HLA-A2-restricted Lassa epitopes in human Lassa fever survivors(American Association of Immunologists, 2020-05-01) Sullivan, Brian MartinMany factors contribute to the selection of epitope-specific T cells. Often, candidate epitopes are generated through in silico prediction of various biological processes, mainly peptide generation and MHC binding, that are then tested in relevant biological assays. This is especially true of epitopes derived from BSL-4 pathogens or where relevant patient samples are difficult to obtain. Two previous studies identified CD8+ T cell epitopes from the Lassa virus glycoprotein through in silico prediction, experimental MHC binding assays, and epitope generation in HLA-A2 transgenic mice. Using samples from ten HLA-A\*02:01 Lassa fever survivors, we tested whether these previously described epitope-specific CD8+ T cells were present and their relation to the broader Lassa virus-specific T cell response. Using overnight stimulation assays, we detected robust LASV-specific responses to the glycoprotein and nucleoprotein, but only one of the three epitopes (GP60–68)shown to be present and protective in mice made a substantial contribution to the overall LASV-specific response. Using a more sensitive proliferation assay, we detected the remaining two epitopes in some individuals at a very low frequency. Overall, this study shows the limitations of epitope discovery through in silico prediction, MHC binding and transgenic mouse models and highlights the complex nature of T cell selection during natural infection of humans.Item Surveillance of COVID-19 in Cameroon: Implications for policymakers and the healthcare system(AOSIS, 2021-01-29) Bonnechère, BrunoAt first less impacted than the rest of the world, African countries, including Cameroon, are also facing the spread of COVID-19. This study aimed to analyze the spread of the COVID-19 in Cameroon, one of the most affected countries in sub- Saharan Africa. We used the data from the Africa Centre for Disease Control and Prevention, reporting the number of confirmed cases and deaths, and analyzed the regularity of tests and confirmed cases and compared those numbers with neighboring countries. We tested different phenomenological models to model the early phase of the outbreak. Since the first reported cases on the 7th of March, 18,662 people have been diagnosed with COVID-19 as of the 24th of August, 186,243 tests have been performed, and 408 deaths have been recorded. New cases have been recorded only in 50% of the days since the first reported cases. There are considerable disparities in the reporting of daily cases, making it difficult to interpret these numbers and to model the evolution of the pandemic with the phenomenological models. Currently, following the finding from this study, it is challenging to predict the evolution of the pandemic and to make comparisons between countries as screening measures are so sparse. Monitoring should be performed regularly to provide a more accurate estimate of the situation and allocate healthcare resources more efficiently.Item Identification of Common CD8+T Cell Epitopes from Lassa Fever Survivors in Nigeria and Sierra Leone(American Society for Microbiology, 2020-04-06) Sakabe, SaoriThe high morbidity and mortality associated with clinical cases of Lassa fever, together with the lack of licensed vaccines and limited and partially effective interventions, make Lassa virus (LASV) an important health concern in its regions of endemicity in West Africa. Previous infection with LASV protects from disease after subsequent exposure, providing a framework for designing vaccines to elicit similar protective immunity. Multiple major lineages of LASV circulate in West Africa, and therefore, ideal vaccine candidates should elicit immunity to all lineages. We therefore sought to identify common T cell epitopes between Lassa fever survivors from Sierra Leone and Nigeria, where distinct lineages circulate. We identified three such epitopes derived from highly conserved regions within LASV proteins. In this process, we also identified nine other T cell epitopes. These data should help in the design of an effective pan-LASV vaccine.Item Assessment of the Quality of Newly Constructed Hand-Dug Well Usetd for Drinking and Their Treatment System at Kenema Town, Kenema District, Eastern, Sierra Leone(Science Publishing Group, 2023-05-25) Umaru, KannehThe tremendous increase in the human population increase the stress on both surface and groundwater and it is believed that at the beginning of human civilization itself, groundwater was the most trusted form of drinking water because of the filtering effect of the aquifer however, in the present world drinking water directly from the source without proper treatment is very tough and risky for the health. Kenema District is a district in the Eastern Province of Sierra Leone, its capital and largest city is Kenema City, which is the third most populous city in Sierra Leone, after Freetown and Bo Both the physical and chemical Parameters investigated are within the WHO acceptable limits, except one of bioteriological parameters (non- faecal coliform). Tables 1, 3, and 4 show high statistical mean values for the Non-Faecal Coliform bacteria in the hand dug wells. Diema Hand Dug Well (12.00 cfu/100ml), Ansarul Hand Dug Well (11.67 cfu/100ml) and the combined statistical mean value (10.78cfu/100ml) of the Non-Faecal Coliform bacteria and all the values fell out of World Health Organization (WHO) permissible limit. However, Islamic Hand Dug Well has a statistical mean value of 8.67 cfu/100ml of Non-Faecal Coliform Value which is within the WHO permissible limit (<10cfu/100ml). The combined statistical mean value for Diema, Islamic, and Ansarul hand dug well for the following physiochemical parameters (pH 7.14, Turbidity 2.46NTU, Conductivity 196.56, TDS 100.11mg, Ammonia 0.02mg/l, Nitrite 0.02mg/l, Nitrate 0.06mg/l, Phosphate 6.15mg/l, Cadmium 0.00gm/l, Copper 0.02mg/l, Iron 0.03mg/l and Zinc 2.67mg/l) are all within the World Health Organization permissible limits (Table 4). Non-faecal coliforms were discovered in all of the wells and boreholes examined and analyzed in a similar investigation to identify the bacteriological pollution of groundwater sources.Item Use of Real Object Media to Improve Students' Multiplication Learning Outcomes in Elementary School Classes(Muhammadiyah University of Malang, 2024-07-17) Hasanah, Diana AgustinaPenelitian ini bertujuan untuk mengamati penggunaan media benda nyata dalam meningkatkan hasil belajar siswa pada materi perkalian di kelas II Sekolah Dasar. Latar belakang penelitian ini adalah rendahnya hasil belajar matematika siswa pada materi perkalian yang masih di bawah Kriteria Ketuntasan Minimal (KKM). Subjek penelitian ini adalah siswa kelas II SDN 1 Sukamanah yang berjumlah 20 orang, yang terdiri dari 10 orang siswa laki-laki dan 10 orang siswa perempuan. Penelitian Tindakan Kelas (PTK) ini dilaksanakan pada semester ganjil tahun pelajaran 2023/2024 dengan menggunakan media benda nyata yang terdiri dari dua siklus. Metode pengumpulan data dilakukan melalui evaluasi, dan alat yang digunakan untuk mengumpulkan data adalah tes tulis pilihan ganda. Analisis data dilakukan secara mekanis dengan menggunakan persentase data kuantitatif yaitu hasil belajar. Hasil penelitian menunjukkan adanya peningkatan yang signifikan hasil belajar matematika pada materi perkalian di kelas II Sekolah Dasar. Berdasarkan analisis ketuntasan hasil belajar siswa, data awal menunjukkan presentase ketuntasan sebesar 35% dengan rata-rata kelas mencapai 57,5 yang belum mencapai KKM yang ditetapkan yaitu 70. Setelah menggunakan alat peraga berupa media benda nyata pada siklus I ketuntasan mencapai 30% dengan nilai rata-rata 57,5. Pada siklus II ketuntasan meningkat menjadi 70% dengan nilai rata-rata 72,5. Oleh karena itu, siklus PTK yang dilaksanakan secara berulang menunjukkan bahwa penggunaan benda nyata efektif dalam meningkatkan hasil belajar siswa pada konsep perkalian. Dengan melibatkan media benda nyata, pembelajaran perkalian menjadi lebih menyenangkan dan relevan bagi siswa sehingga dapat mencapai hasil belajar yang lebih baik.Item EXAMINE THE EFFECTS OF GOODS AND SERVICES TAX (GST) AND ITS COMPLIANCE: REFERENCE TO SIERRA LEONE(GRDS Publishing, 2024-03-15) Kaira, LaminThis study analyzes the effects of (GST) and how it is being implemented in Sierra Leone. GST replaces previous taxes, including domestic sales tax, import sales tax, entertainment tax, hotel room tax, restaurant tax, food tax etc. The objectives of this study are to know the effect of GST on the Sierra Leone Economy, to know if GST implementation will lead to an increase in prices of goods and services; to assess GST compliance rate in Sierra Leone; and to know the reasons for GST implementation in Sierra Leone. The data collection method used both primary and secondary sources the study's participants were 89 employees of NRA and business owners in Sierra Leone 2021 to 2023. Questions were analyzed using SPSS in the form of descriptive analysis, chart, and correlation coefficient. The results showed that GST implementation has positive effects on Sierra Leone Economy. The introduction of GST is to boost revenue and promote economic growth in Sierra Leone. GST introduction in Sierra Leone has resulted in increased prices of goods and services. It is recommended that the NRA should provide tax education and awareness and provide availability and accessibility of technological infrastructure for GST implementation in the country.Item Trends and spatial patterns of human immunodeficiency virus prevalence among men and women aged 15–49 in Sierra Leone: evidence from the 2008, 2013 and 2019 Demographic and Health Surveys(BMJ, 2025-08-01) Fornah, LovelBACKGROUND: Human immunodeficiency virus prevalence remains a major public health concern in Sierra Leone. This study examines the trends and spatial patterns of human immunodeficiency virus prevalence among men and women in Sierra Leone using data from the 2008, 2013, and 2019 Sierra Leone Demographic and Health Surveys (SLDHS). METHOD: We analyzed data from three SLDHS conducted in 2008, 2013, and 2019. Men and women aged 15-49 who tested for HIV were eligible. A trend analysis was used to examine the change in human immunodeficiency virus prevalence. Spatial autocorrelation and Moran's I statistic were used to assess the spatial distribution of human immunodeficiency virus prevalence. We used the 2019 SLDHS to determine the predictors of human immunodeficiency virus prevalence using geographically weighted regression. RESULTS: The study found that human immunodeficiency virus prevalence was 1.5% in 2008, 1.3% in 2013 and 1.7% in 2019. From 2008 to 2019, human immunodeficiency virus prevalence in the Western and Northwest regions increased, with a consistent rise in the Southern region and an increase in the Northern regions. We identified hotspots for human immunodeficiency virus prevalence in Koinadugu, Kono, Bo and Kailahun districts. In 2008 and 2013, the Kono district had the highest human immunodeficiency virus prevalence, while the western areas, Port Loko and Bombali districts had the highest risk in 2019. Our geographically weighted regression analysis indicated that, age 15-19, urban residence and no formal education were predictors of HIV prevalence in 2019. CONCLUSION: The human immunodeficiency virus prevalence across different districts is inconsistent, with Western areas having a higher prevalence while Southern and Northern regions showed varying trends. Hotspot regions were identified, with changes in high-risk areas over time. Predictors of human immunodeficiency virus prevalence in hotspot areas include age 15-19, urban residents and no formal education. The study suggests the need for prevention and intervention programmes for these high-risk areas and groups to reduce human immunodeficiency virus transmission in Sierra Leone.Item Revolutionizing University Mathematics Education: The Impact of Deep Learning and Educational Technology(Muhammadiyah University of Malang, 2025-01-31) Budiarti, ErnaThe integration of deep learning into university mathematics education presents transformative possibilities. This study conducted a Systematic Literature Review (SLR), examining 80 studies from sources like IEEE Xplore, ScienceDirect, Scopus, and Google Scholar. The focus was on the application of deep learning in formal education, excluding non-educational contexts. Findings indicate that deep learning enhances learning through interactive visualization and simulation tools, with virtual reality applications improving geometry and statistics comprehension by up to 30% compared to traditional methods. Challenges such as limited infrastructure and resistance from lecturers were identified. To address these, the study advocates for regular technology-based training for lecturers and gradual curriculum integration of technology. Strengthening collaboration between universities, the technology industry, and policymakers is recommended to support implementation. Additionally, the proposal of an online evaluation platform is suggested to continuously monitor student competency improvements. A systematic approach to implementing deep learning is anticipated to optimize mathematics education effectiveness in universities, preparing students for complex workforce challenges.Item Recycling Pineapple Leaf (Ananas Comosus) Agro-Waste as an Alternative Raw Material to Produce Eco-Friendly Paper(Science Publishing Group, 2025-10-10) Yongai, IsaacThis study investigates the viability of recycling pineapple leaf agro-waste (PALF) as a sustainable and eco-friendly alternative to wood-based pulp for paper production in Sierra Leone. The research addresses the dual challenges of heavy reliance on imported paper products and the environmental problem of agricultural waste mismanagement. An experimental design was employed to compare two distinct pulping techniques: a chemical method using an 11% Sodium Hydroxide (NaOH) solution and a traditional method using a locally sourced wood ash lye solution. Fibers were extracted from pineapple leaves, converted into pulp, and then formed into handmade paper sheets. The physical and mechanical properties of the resulting papers, including thickness, water absorbency, writing quality, tensile strength, and tearing resistance, were systematically analyzed. The findings indicate that the NaOH pulping method produced higher quality paper, exhibiting superior tensile strength (500 N/m breaking force), a smoother finish, and minimal ink feathering, making it suitable for writing and printing applications. In contrast, the wood ash lye method yielded a functional but lower-grade paper that was thicker, coarser, and possessed lower mechanical strength (410 N/m breaking force). The study concludes that pineapple leaf agro-waste is a highly promising non-wood fiber source for paper production. While the NaOH method is technically superior, the wood ash lye method presents a compelling, low-cost, and accessible alternative for small-scale, rural enterprises in resource-limited settings like Sierra Leone. This research demonstrates a practical model for waste valorization that aligns with circular economic principles, promoting environmental sustainability, green entrepreneurship, and import substitution. The study recommends scaling up production for pilot testing, optimizing chemical usage, and developing training programs to support local adoption of these sustainable technologies. This study, therefore, recommends that future researchers should explore optimal NaOH concentrations and environmentally friendly alternatives to reduce chemical use without compromising quality, and combining PALF pulp with other fibers (e.g., recycled paper, banana pseudo-stem pulp) could improve paper properties and reduce costs.Item Key Factors Influencing the Quality of Mathematics Education in Rural Communities. A case study on Lower Bambara Chiefdom - Kenema District - Sierra Leone(2025-10-24) Sandy, ChristianThe study examines key factors influencing mathematics education quality in rural Sierra Leone, highlighting persistent challenges such as resource shortages, inadequate teacher training, and low student performance. Using a mixed methods approach, data from 50 pupils and 10 teachers across ten schools revealed that most students underperform academically, with an average score of 31.5 out of 100. Teachers generally possess moderate experience, yet many are rated as poor performers, underscoring the need for professional development. Perception surveys indicated that both pupils and teachers recognize teacher quality and student engagement as crucial factors affecting learning outcomes. Statistical analyses, including ANOVA, identified teaching quality (p=0.008), resource adequacy (p=0.025), and pupil engagement (p=0.045) as significantly influencing mathematics instruction, while curriculum relevance was not statistically significant. The results underscore that improving teacher competence, increasing instructional resources, and fostering student motivation are vital for enhancing mathematics learning in rural contexts. Addressing infrastructural deficits and implementing targeted interventions can promote equitable access to quality education and booster academic achievement. Ultimately, the findings provide empirical evidence for policymakers and educators to prioritize resource allocation, teacher training, and student engagement strategies, fostering sustainable improvements in mathematics education and supporting broader socioeconomic development in Sierra Leone.