Hasil untuk "History of Africa"

Sang Yun Kwon, AbdelRahim Elmadany, Muhammad Abdul-Mageed

Language Identification (LID) is the task of determining the language of a given text and is a fundamental preprocessing step that affects the reliability of downstream NLP applications. While recent work has expanded LID coverage for African languages, existing approaches remain limited in (i) the number of supported languages and (ii) their ability to make fine-grained distinctions among closely related varieties. We introduce AfroScope, a unified framework for African LID that includes AfroScope-Data, a dataset covering 713 African languages, and AfroScope-Models, a suite of strong LID models with broad language coverage. To better distinguish highly confusable languages, we propose a hierarchical classification approach that leverages Mirror-Serengeti, a specialized embedding model targeting 29 closely related or geographically proximate languages. This approach improves macro F1 by 4.55 on this confusable subset compared to our best base model. Finally, we analyze cross linguistic transfer and domain effects, offering guidance for building robust African LID systems. We position African LID as an enabling technology for large scale measurement of Africas linguistic landscape in digital text and release AfroScope-Data and AfroScope-Models publicly.

N. N. Ngcobo, L. J. Mathibe

We present a case of a woman hospitalized with a known history of systemic lupus erythematosus (SLE) and Type 2 diabetes mellitus. She was referred from a local public district hospital in Richards Bay (KwaZulu-Natal, South Africa) to a tertiary/academic hospital, where her clinical assessment suggested inflammatory myositis. Initially, she presented with a progressively worsening skin rash and proximal muscle weakness. The rash began as red lesions that later healed with pigmentation, primarily in sun-exposed areas. Two weeks after these initial symptoms, she developed scalp hair loss. Her condition eventually deteriorated to the extent that she became bed-bound. A skin biopsy showed dermatomyositis, and a subsequent muscle biopsy confirmed the disease’s typical features. Treatment with rituximab led to improvements in both creatine kinase levels and muscle strength, suggesting its effectiveness in managing her condition.

Parker Riley, Siamak Shakeri, Waleed Ammar et al.

We present TyDi QA-WANA, a question-answering dataset consisting of 28K examples divided among 10 language varieties of western Asia and northern Africa. The data collection process was designed to elicit information-seeking questions, where the asker is genuinely curious to know the answer. Each question in paired with an entire article that may or may not contain the answer; the relatively large size of the articles results in a task suitable for evaluating models' abilities to utilize large text contexts in answering questions. Furthermore, the data was collected directly in each language variety, without the use of translation, in order to avoid issues of cultural relevance. We present performance of two baseline models, and release our code and data to facilitate further improvement by the research community.

Roy N. Platt II, Egie E. Enabulele, Ehizogie Adeyemi et al.

Abstract The human parasitic fluke, Schistosoma haematobium hybridizes with the livestock parasite S. bovis in the laboratory, but the frequency of hybridization in nature is unclear. Here, we analyze 34.6 million single nucleotide variants in 162 samples from 18 African countries, revealing a sharp genetic discontinuity between northern and southern S. haematobium. We find no evidence for recent hybridization. Instead the data reveal admixture events that occurred 257–879 generations ago in northern S. haematobium populations. Fifteen introgressed S. bovis genes are approaching fixation in northern S. haematobium with four genes potentially driving adaptation. Further, we identify 19 regions that are resistant to introgression; these are enriched on the sex chromosomes. These results (i) suggest strong barriers to gene flow between these species, (ii) indicate that hybridization may be less common than currently envisaged, but (iii) reveal profound genomic consequences of rare interspecific hybridization between schistosomes of medical and veterinary importance.

Tshilidzi Ratshitanga

Tshilidzi Ratshitanga is a Mitchell Fellow and PhD graduate of the School of Public Policy and Administration, University of Delaware, United States of America. He holds an MPhil and Bachelor’s degrees from the University of Port Elizabeth (currently Nelson Mandela University) and RAU (now University of Johannesburg), respectively. Dr. Ratshitanga is also Chairman and Founder of the New Cities New Economies Group and the African Global Consortium. Dr. Ratshitanga previously worked as a senior manager at the South African government’s Government Communications and Information System (GCIS) before joining the private sector and becoming involved with companies in the property development and mining industries. He currently serves on a number of boards, including that of the Mapungubwe Institute for Strategic Reflection (MISTRA). He previously served as the Chairman of both Bokamoso Barona Investment Trust and Kaborona Investment Holdings. He also served as the Chairman of the Housing Development Agency (HDA), Deputy Chairperson of the Gauteng Growth and Development Agency (GGDA), and Chairman of the Innovation Hub (TIH). Dr. Ratshitanga also served as the official Special Advisor to the current South Africa’s Deputy President, Mr. Paul Mashatile, and still advises him in a private capacity. Tshilidzi is a social activist. He is an active member of South Africa’s ruling party, the African National Congress (ANC). He previously served as Secretary General of both the Congress of South African Students (COSAS) and the South African Students’ Congress (SASCO), which are both ANC-aligned progressive student movements. Dr. Ratshitanga also served the African National Congress Youth League (ANCYL) in Gauteng Province and was also a Commissioner of the ANC’s 2012 National Congress Elections Commission. Dr. Ratshitanga is the author of the book “New Cities, New Economies: South Africa and Africa’s Grand Plan, A Pan-African Economic Revolution.” In his interview he tells his vision about “New cities. New economies” and his opinion on the decolonization of African spatial development.

G. Aad, E. Aakvaag, B. Abbott et al.

A combination of searches for singly and doubly charged Higgs bosons, H± and H±±, produced via vector-boson fusion is performed using 140 fb−1 of proton–proton collisions at a centre-of-mass energy of 13 TeV, collected with the ATLAS detector during Run 2 of the Large Hadron Collider. Searches targeting decays to massive vector bosons in leptonic final states (electrons or muons) are considered. New constraints are reported on the production cross-section times branching fraction for charged Higgs boson masses between 200 GeV and 3000 GeV. The results are interpreted in the context of the Georgi-Machacek model for which the most stringent constraints to date are set for the masses considered in the combination.

Alaa Hamid, Rimah Elsir, Elsafia Abbas et al.

Abstract Background Despite significant progress in malaria control, the disease remains a major cause of morbidity and mortality, particularly among children under five in sub-Saharan Africa. Sudan, with substantial malaria burden, faces challenges in integrating new interventions, such as malaria vaccines, into national immunization programmes. This study aimed to assess Sudanese caregivers' awareness and acceptance of the malaria vaccine and to identify factors influencing their willingness to vaccinate their children. Methods A descriptive, cross-sectional mixed-methods study was conducted from November 2024 to January 2025 in two public primary healthcare centres in Sudan. A total of 159 caregivers participated through consecutive sampling. Quantitative data on sociodemographic factors, malaria experience, vaccine awareness, and acceptance were collected via structured questionnaires and analysed using descriptive and inferential statistics. Qualitative responses were gathered on reasons behind vaccine hesitancy and analysed thematically. Results Caregiver acceptance of the malaria vaccine was high (86.2%) despite limited prior awareness (11.3%). Acceptance was significantly associated with perceived malaria severity (p < 0.001), caregivers' own vaccination history (p = 0.034), and children's complete immunization (p = 0.047). Qualitatively, vaccine safety concerns predominated, alongside scepticism toward healthcare systems and a perceived lack of vaccine necessity. Trusted health information primarily came from healthcare providers (66%). Conclusion Sudanese caregivers demonstrate strong willingness to vaccinate their children against malaria, driven largely by perceived disease threat and trust in routine immunization services. Effective vaccine introduction should prioritize targeted communication to address safety concerns and integrate the malaria vaccine within existing immunization frameworks to sustain high uptake.

Jorge Fabila, Víctor M. Campello, Carlos Martín-Isla et al.

Africa faces significant challenges in healthcare delivery due to limited infrastructure and access to advanced medical technologies. This study explores the use of federated learning to overcome these barriers, focusing on perinatal health. We trained a fetal plane classifier using perinatal data from five African countries: Algeria, Ghana, Egypt, Malawi, and Uganda, along with data from Spanish hospitals. To incorporate the lack of computational resources in the analysis, we considered a heterogeneous set of devices, including a Raspberry Pi and several laptops, for model training. We demonstrate comparative performance between a centralized and a federated model, despite the compute limitations, and a significant improvement in model generalizability when compared to models trained only locally. These results show the potential for a future implementation at a large scale of a federated learning platform to bridge the accessibility gap and improve model generalizability with very little requirements.

Joyce Charles Shikali, Paul Samwel Muneja

The study examined access to library information resources by university students during the outbreak of the COVID-19 pandemic. The study investigated measures that were adopted by academic libraries for smooth delivery of library information resources to their patrons. It also identified technological tools that were employed by libraries to facilitate access to library information resources. We also investigated the challenges faced by students in accessing library information resources. A systematic literature review approach using PRISMA guidelines was employed to investigate the relevant literature on the subject. The keyword search strategy was employed to search for relevant literature from four scholarly databases Scopus, emerald, Research4life, and Google Scholar. In this study, 23 studies that fulfilled the criteria were included. The findings revealed that the majority of the reviewed studies indicate that, during the COVID-19 pandemic many academic libraries in Africa adopted different approaches to facilitate access to library information resources by university students including expanding access to electronic resources off-campus, virtual reference services, circulation and lending services. To support access to different library services and information resources academic libraries in Africa used various digital technological tools like social media, library websites, email and video conferencing. Moreover, the study revealed that limited access to internet services and ICT devices, inadequate electronic library collection and inadequate digital and information literacy were the major challenges faced by patrons during the pandemic. This study recommends investment in ICT infrastructures and expanding electronic resource collections which are vital resources in the digital era.

Michael Scheuerer, Claudio Heinrich-Mertsching, Titike K. Bahaga et al.

Seasonal climate forecasts are commonly based on model runs from fully coupled forecasting systems that use Earth system models to represent interactions between the atmosphere, ocean, land and other Earth-system components. Recently, machine learning (ML) methods are increasingly being investigated for this task where large-scale climate variability is linked to local or regional temperature or precipitation in a linear or non-linear fashion. This paper investigates the use of interpretable ML methods to predict seasonal precipitation for East Africa in an operational setting. Dimension reduction is performed by decomposing the precipitation fields via empirical orthogonal functions (EOFs), such that only the respective factor loadings need to the predicted. Indices of large-scale climate variability--including the rate of change in individual indices as well as interactions between different indices--are then used as potential features to obtain tercile forecasts from an interpretable ML algorithm. Several research questions regarding the use of data and the effect of model complexity are studied. The results are compared against the ECMWF seasonal forecasting system (SEAS5) for three seasons--MAM, JJAS and OND--over the period 1993-2020. Compared to climatology for the same period, the ECMWF forecasts have negative skill in MAM and JJAS and significant positive skill in OND. The ML approach is on par with climatology in MAM and JJAS and a significantly positive skill in OND, if not quite at the level of the OND ECMWF forecast.

G. Lyon, A. Mehta, Jay B. Varkey et al.

N. J. Fagundes, N. Ray, M. Beaumont et al.

L. Cavalli-Sforza, M. Feldman

E. Petersen, I. Abubakar, C. Ihekweazu et al.

The identification of monkeypox in 3 separate patients in the United Kingdom in September raised media and political attention on an emerging public health threat. Nigeria, whose last confirmed case of monkeypox was in 1978, is currently experiencing an unusually large and outbreak of human monkeypox cases, a ‘One Human-Environmental-Animal Health’ approach is being effectively used to define and tackle the outbreak. As of 13th October 2018, there have been one hundred and sixteen confirmed cases the majority of whom are under 40 years. Over the past 20 years ten Central and West African countries have reported monkeypox cases which have risen exponentially. We review the history and evolution of monkeypox outbreaks in Africa and USA, the changing clinical presentations, and discuss possible factors underlying the increasing numbers being detected including the cessation of smallpox vaccination programs. Major knowledge gaps remain on the epidemiology, host reservoir, and emergence, transmission, pathogenesis and prevention of monkeypoz.

K. Bryc, A. Auton, M. Nelson et al.

William J. Wolf

I apply Dawid's Meta-Empirical Assessment (MEA) methodology to the theory of cosmological inflation. I argue that applying this methodology does not currently offer a compelling case for ascribing non-empirical confirmation to cosmological inflation. In particular, I argue that despite displaying strong instances of Unexpected Explanatory Coherence (UEA), it is premature to evaluate the theory on the basis of the No Alternatives Argument (NAA). More significantly though, I argue that the theory of cosmological inflation fails to sustain a convincing Meta-Inductive Argument (MIA) because the empirical evidence and theoretical successes that it seeks to draw meta-empirical support from do not warrant a meta-inductive inference to inflation. I conclude by assessing how future developments could pave the way towards crafting a more compelling case for the non-empirical confirmation of cosmological inflation.

Mounib M. Sabounji, Hilaire Lissimo, Amina Deme

Abstract Background Childhood-onset rheumatoid arthritis (CORA), known as rheumatoid factor (RF)-positive juvenile idiopathic arthritis is a type of juvenile idiopathic arthritis that shares the same genetic factors and clinical features as adult-onset rheumatoid arthritis. In Africa, CORA hasn’t been the subject of a specific study. Objectives The aim of this study is to describe the clinical features, disease activity, functional disability, and treatment of CORA at diagnosis in Senegal and compare the findings to other CORA populations. Methods We conducted a mixed cohort study by reviewing the medical records of patients diagnosed with CORA with an age of symptom onset < 18 years according to the 2019 PRINTO provisional criteria for RF-positive JIA from January 2020 to December 2022 at rheumatology department of Aristide Le Dantec Hospital in Dakar, Senegal. We collected demographic, clinical, paraclinical and therapeutic data. Disease activity score was assessed by DAS28-ESR and DAS28-CRP. Functional disability was assessed using Health Assessment Questionnaire (HAQ) or Childhood HAQ. Results A total of 21 patients were included. Eighteen (85.7%) were Females. The mean age at symptom onset was 13.0 ± 3.0 years, and at diagnosis was 16.4 ± 4.2 years. Morning stiffness, joint swelling, and joint deformities were found in 20, 18 and 13 patients respectively. Four patients had a family history of rheumatoid arthritis. Five patients had extra-articular involvement such as rheumatoid nodules. Two patients had interstitial lung disease. The biological inflammatory syndrome was found in 90% of cases. 16 of 21 (76.2%) patients had positive RF, and 18 of 20 (90%) patients had positive Anti-CCP. Seven of 12 (58.3%) patients had positive anti-nuclear antibodies. The mean DAS28-ESR was 5.7 ± 1.0. Fifteen (71.4%) patients had high disease activity (DAS28-ESR > 5.1). The mean DAS28-CRP was 5.4 ± 1.1. The median HAQ was 2.12 with a mean HAQ of 1.9. Nineteen (90.5%) patients were treated with methotrexate, while 17 (81%) had a combination of methotrexate and hydroxychloroquine. Oral prednisone was used in 17 (81%) cases. Non-steroidal anti-inflammatory drugs were used in 4 cases (19%). After 6 months of treatment, mean DAS28-CRP was 2.9. Conclusion In our study, CORA mainly affects 13-year-old girls, characterised by high disease activity with joint deformity and significant functional impairment. Treatment is mainly based on methotrexate, prednisone and hydroxychloroquine. Further studies are needed to determine the exact clinical phenotype of this disease.

O. Hanotte, D. Bradley, J. Ochieng et al.

J. Fernández-Palacios, L. de Nascimento, R. Otto et al.

D. Conrad, M. Jakobsson, G. Coop et al.