10 research outputs found
White Matter Microstructure Abnormalities in Individuals at High Risk for Psychosis: A Meta-Analysis of Fractional Anisotropic Changes Associated With Transition to Psychosis
No full textAims
Recent studies have focussed on detecting white matter abnormalities in subjects who transition to psychosis (UHR-T). Research suggests that fractional anisotropy (FA), may be decreased in UHR-T. However, global and regional findings have been inconsistent. By objectively combining data in a meta-analysis, we have investigated white matter alterations associated with transition, by comparing FA in UHR-T with subjects that do not transition (UHR-NT) and healthy volunteers.
Methods
The meta-analysis was registered on PROSPERO (ID: CRD42021265348) and followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses PRISMA guidance. A systematic database search of PUBMED and EMBASE identified reports, which were screened by 2 independent researchers (CN and DD) for inclusion, from inception to 20 July 2021. Discrepancies were decided on consensus with a third researcher (KM). Reference lists of eligible studies were also screened. Authors of screened reports were contacted to provide parametric maps. Coordinate-based meta-analysis was conducted using Seed-based d-Mapping software to combine parametric map and coordinate data from reports, using a random-effects model. Quality and risk of bias analysis were conducted using the Newcastle-Ottowa Scale. Heterogeneity and sensitivity analyses were also conducted.
Results
The search strategy identified 889 potential studies, from which 6 met eligibility criteria. A total of 71 UHR-T, 142 UHR-NT and 148 healthy volunteers were included. Weighted-mean decreases in FA were observed in UHR-T compared with: UHR-NT (d = −0.99; p < 0.0001; 95% CI −1.43 to −0.55); and healthy volunteers (d = −0.91; p = 0.04; 95% CI −1.78 to −0.05). The level of heterogeneity for the former was not significant. For UHR-T, regional FA decreases were observed in areas including the left genu of the corpus callosum (Z-score = −1.76, 204 voxels, p < 0.0001) compared with UHR-NT, while FA increases were most observed in the white matter region adjacent to the left postcentral gyrus (Z-score = 1.64, voxels = 16, p < 0.0001). These findings persisted despite sensitivity analyses.
Conclusion
The findings suggest that white matter alterations, specifically in left frontotemporal tracts, are associated with an increased risk of transition to psychosis. The neurobiological implications of these findings, and their contribution to UHR-T prediction efforts, are explored, as are avenues for further research.
Additional Author: Mr Gunnar Gronlid.
A Review of Automated Text Summarization Models on Diverse Datasets: An Evaluation Perspective
No full textThis paper reviews Automatic Text Summarization which is one of the tasks in Natural Language Processing (NLP). It is driven by speedy increase in textual data across domains. The reviews systematically examined the recent advancements in Extractive, Abstractive and hybrid automatic text Summarization Models between 2019 and 2025 using Preferred Reporting Items for Reviews and Meta-Analysis (PRISMA). Selected and relevant related papers were taken from Elsevier, Google scholar, IEEE Xplorer, ACM digital library, and Springer. After removing duplicates (n=96), 174 irrelevant records were removed to meet the inclusion criteria covering models like BERT (Bidirectional Encoder Representations from Transformers), BART (Bidirectional and Auto Regressive Transformers), T5 (Text-To-Text Transformer), TextRank, LSA (Latent Semantic Analaysis), and PEGASUS (Pre-training with Extracted Gap-sentences for Abstractive Summarization Sequence-to-to-Sequence Models) across Diverse datasets including news, scholarly and technical corpora. Extractive approaches depicted strong lexical accuracy and computational efficiency, whereas transformer-based Abstractive models showed superior semantic coherence but needed higher computational costs. This review paper also highlighted persistent gaps including dataset bias, long-document Summarization, hallucination in generative models, and over reliance on traditional metrics such as ROUGE.The results show the need for cross-domain evaluation, hybrid model integration, and adoption of advanced semantic metrics like BERTScore and MoverScore. Future directions should take into priority cross-domain benchmarks, standardized multi-metric evaluation, hybrid approach exploration and testing for long and multilingual documents. In furtherance, Reproducible Reporting of Computational cost such as GPU-hours and failure modes such as hallucinations will support more practical comparisons
The evolution of poverty and welfare in Nigeria, 1985-92
No full textThe authors profile Nigerian poverty, showing its evolution from 1985 to 1992. This paper is divided into 6 sections, beginning with an overview. Section 2 looks at the sources of data used. Section 3 examines household income and expenditure distribution, interprets poverty indices, and calculates relative poverty lines for Nigeria. Section 4, the paper's core, presents the spatial characteristics of poverty in Nigeria and their evolution over the seven-year period, indicating in which regions and states the poor are located and the extent and severity of their poverty; lays out the poor's basic demographic characteristics including time use and employment patterns, detailing how these have evolved; features the roles the poor play in various sectors of the economy; and discuss how changes in poverty could be explained by growth-related and redistribution factors. Section 5 discusses the evolution of expenditures and explains how expenditure patterns correspond to poverty. Section 6 presents conclusions, among them: the extremely poor -who dominate the ranks of the uneducated- became poorer, while all other income groups had a higher standard of living; an increase in mean per capita household spending reduced the proportion of the population in poverty but different regions did not share equally in the benefits of growth; household spending grew faster in southern and central Nigeria and slower in the north; and poverty was overwhelmingly rural and regional, but also greatly influenced by age, educaton, and the nature of employment.Public Health Promotion,Environmental Economics&Policies,Health Economics&Finance,Poverty Reduction Strategies,Services&Transfers to Poor,Poverty Assessment,Environmental Economics&Policies,Achieving Shared Growth,Health Economics&Finance,Poverty Lines
Assessment of the global Copernicus, NASADEM, ASTER and AW3D digital elevation models in Central and Southern Africa
No full textDATA AVAILABILITY STATEMENT :
The data that support the findings of this study are available from the corresponding author upon reasonable request.Validation studies of global Digital Elevation Models (DEMs) in the existing literature are limited by the diversity and spread of landscapes, terrain types considered and sparseness of groundtruth. Moreover, there are knowledge gaps on the accuracy variations in rugged and complex landscapes, and previous studies have often not relied on robust internal and external validation measures. Thus, there is still only partial understanding and limited perspective of the reliability and adequacy of global DEMs for several applications. In this study, we utilize a dense spread of LiDAR groundtruth to assess the vertical accuracies of four medium-resolution, readily available, free-access and global coverage 1 arc-second (30 m) DEMs: NASADEM, ASTER GDEM, Copernicus GLO-30, and ALOS World 3D (AW3D). The assessment is carried out at landscapes spread across Cape Town, Southern Africa (urban/industrial, agricultural, mountain, peninsula and grassland/shrubland) and forested national parks in Gabon, Central Africa (low-relief tropical rainforest and high-relief tropical rainforest). The statistical analysis is based on robust accuracy metrics that cater for normal and non-normal elevation error distribution, and error ranking. In Cape Town, Copernicus DEM generally had the least vertical error with an overall Mean Error (ME) of 0.82 m and Root Mean Square Error (RMSE) of 2.34 m while ASTER DEM had the poorest performance. However, ASTER GDEM and NASADEM performed better in the low-relief and high-relief tropical forests of Gabon. Generally, the DEM errors have a moderate to high positive correlation in forests, and a low to moderate positive correlation in mountains and urban areas. Copernicus DEM showed superior vertical accuracy in forests with less than 40% tree cover, while ASTER and NASADEM performed better in denser forests with tree cover greater than 70%. This study is a robust regional assessment of these global DEMs.The Commonwealth Scholarship Commission and the Foreign, Commonwealth and Development Office in the UK and the University of Cape Town Postgraduate Funding Office.https://www.tandfonline.com/loi/tgsi20hj2024Geography, Geoinformatics and MeteorologySDG-15:Life on lan
Demilitarisation Nigeria and South Africa compared
No full textIn sub-Saharan African countries that have made democratic transition from military
rule and military-backed authoritarian regimes, state elites have embarked upon
strategies aimed at demilitarising the new democratic political process. Demilitarisation
of the state and politics has become an imperative because it is decisive for
consolidating democratic politics and for ensuring improvements in public safety and
security. Yet the process of such demilitarisation in these countries has often generated
a paradox, whereby the reduction of the political influence of state institutions of
violence has been associatedw ith rising civil militarism and the prevalenceo f organised
violence in the wider society.
In these circumstances, taking cognisance of the dangers of civil militarism and other
forms of private violence is a priority for designing and implementing demilitarisation
strategies and other security reforms in post-authoritarian African states. Reformminded
political elites and external supporters need to be sensitive to these dangers or
risk perpetuating the shell of electoral democracy that cannot deliver the goal of human
security in the region. This dissertation explored how the current approach to
demilitarisation is related to the problem of civil militarism by examining the case
studies of Nigeria and South Africa. It explains that given the condition of the state in
Africa, demilitarisation of politics after transition from military or military-backed
authoritarianism contributes to the emergence of civil militarism. Based on this finding,
it argues for a comprehensive approach to demilitarisation as a strategy that caters to
both state and societal violence in order to mitigate the risks of civil militarism in the
process
The Politics of the Idea of Partnership: From contemporary aid policy to local health governance in practice in Zambia
No full textThis thesis explores the idea of partnership in contemporary aid policy and practice. Drawing on a multi-disciplinary body of literature that is broadly ‘constructivist’ in orientation, and using the Global Fund to Fight AIDS, Tuberculosis and Malaria, the health Sector-Wide Approach (SWAp) and the health sector in Zambia as case studies, the research uniquely explores how (and why) the idea of partnership is a pervasive feature in aid policy, and how this relates to and shapes local practice, including the practice of politics that this enjoins.
Drawing on textual analysis of policy documents and on qualitative field research conducted in Zambia between November 2008 and July 2009, the thesis provides a number of important and novel insights. Firstly, it shows how the idea of partnership began its contemporary life in the socio-political relations of aid institutions and in the context of an aid crisis in the 1990s. Secondly, it shows how the idea travelled ideationally and geographically, through an elite network of aid agency actors (cf. Mosse, 2007), eventually becoming an expected and symbolic motif of aid policy. Thirdly, the thesis suggests why partnership remains a pervasive policy idea; featuring in SWAp and Global Fund policy because it symbolically conceals the existence of different perspectives about the right relations of health and developmental governance. Fourthly, and at the same time, the thesis shows how partnership is dominantly constructed in aid policy in a depoliticised way – as a technical and economic way to organise action – due to the prevailing power of donor governments and aid agencies in the socio-political processes that produce aid policy and the context of inequality in which aid is governed. Finally, the thesis shows how the depoliticisation of policy is ‘unravelled’ in the health sector in Zambia as partnership is translated, in and through the politics of collaboration, contestation, and compromise (Mosse, 2007, p.2, 2005a p.645; Rossi, 2006; Bending and Rosendo, 2006). This shapes, contorts and constrains local health governance in diverse and unexpected ways
A New Form of Authoritarianism? Rethinking Military Politics in Post-1999 Nigeria
No full textDespite the vast research that has been done on the Nigerian military, virtually all of these studies have failed to critically examine the accepted role of the military in the democratising phase. This is important because the relationship between the political elite and the military in post-military authoritarian states guarantees either democratic consolidation, or its reversal. In Nigeria, despite an appearance of significant progress in subordinating the military institution to democratic civilian authority, the military remains a crucial political actor in the polity. It appears that the military has yet to accept the core democratic principles of civilian oversight of the institution. This thesis, therefore, explores whether a new form of military authoritarianism is emerging in Nigeria, with the aim of understanding Nigeria’s military behaviour in a transitional phase, from prolonged military authoritarianism to democratisation. To examine this military behaviour, Alfred Stepan’s concept of military prerogatives that was used to understand the military’s behaviour in a transitional phase in Latin America is applied to Nigeria.
A crucial understanding of authoritarianism in Nigeria is initially discussed in this study using mainly document analysis strategy to examine whether multi-ethnic states, such as Nigeria, tend to have authoritarian systems. Six hypotheses form the core analysis of this thesis: first, that the military has retained significant military prerogatives; second, that retired military officers are gaining influential political and economic positions; third, autonomous military involvement in human rights abuses since 1999; and fourth, that civilian government oversight remains weak, and facilitates military authoritarianism. These hypotheses are primarily analysed using the elite interview technique. During the first half of 2011, the author conducted field research where serving and retired military officers were interviewed. The fifth hypothesis is that the military has intervened in politics post-1999. The examination of this hypothesis relies primarily on key security-related media reports (mostly newspaper editorials) on the military after 1999. The examination of the final hypothesis, that increases in military expenditures might facilitate a new form of military authoritarianism, relies primarily on descriptive statistical analysis. In addition, this study collated relevant historical materials that relate to the military, utilising national archival collections.
The empirical findings of this research did not identify a new form of military authoritarianism in Nigeria. The study, however, argues that the unrestricted institutional framework accorded the military has contributed significantly to authoritarian practices in the post-military era in Nigeria. This study discovered that there were similarities between the Brazilian and Nigerian militaries in regard to their military spending during their period in power. Both countries had lower defence budgets. Just as in Brazil, it appears that part of the reason the Nigerian military decided to relinquish power in 1999 had to do with its desire to gain a higher budget, something that was precluded in a military government struggling to retain a sense of legitimacy. The military needed a higher budget to modernise and re-professionalise its institution after more than a decade in power. This feature, which the Nigerian military shares with the Brazilian military, appears to justify the application to Nigeria of Alfred Stepan’s concept of military prerogatives.
Global burden of 87 risk factors in 204 countries and territories, 1990–2019: a systematic analysis for the Global Burden of Disease Study 2019
No full textBackground: Rigorous analysis of levels and trends in exposure to leading risk factors and quantification of their effect on human health are important to identify where public health is making progress and in which cases current efforts are inadequate. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 provides a standardised and comprehensive assessment of the magnitude of risk factor exposure, relative risk, and attributable burden of disease. Methods: GBD 2019 estimated attributable mortality, years of life lost (YLLs), years of life lived with disability (YLDs), and disability-adjusted life-years (DALYs) for 87 risk factors and combinations of risk factors, at the global level, regionally, and for 204 countries and territories. GBD uses a hierarchical list of risk factors so that specific risk factors (eg, sodium intake), and related aggregates (eg, diet quality), are both evaluated. This method has six analytical steps. (1) We included 560 risk–outcome pairs that met criteria for convincing or probable evidence on the basis of research studies. 12 risk–outcome pairs included in GBD 2017 no longer met inclusion criteria and 47 risk–outcome pairs for risks already included in GBD 2017 were added based on new evidence. (2) Relative risks were estimated as a function of exposure based on published systematic reviews, 81 systematic reviews done for GBD 2019, and meta-regression. (3) Levels of exposure in each age-sex-location-year included in the study were estimated based on all available data sources using spatiotemporal Gaussian process regression, DisMod-MR 2.1, a Bayesian meta-regression method, or alternative methods. (4) We determined, from published trials or cohort studies, the level of exposure associated with minimum risk, called the theoretical minimum risk exposure level. (5) Attributable deaths, YLLs, YLDs, and DALYs were computed by multiplying population attributable fractions (PAFs) by the relevant outcome quantity for each age-sex-location-year. (6) PAFs and attributable burden for combinations of risk factors were estimated taking into account mediation of different risk factors through other risk factors. Across all six analytical steps, 30 652 distinct data sources were used in the analysis. Uncertainty in each step of the analysis was propagated into the final estimates of attributable burden. Exposure levels for dichotomous, polytomous, and continuous risk factors were summarised with use of the summary exposure value to facilitate comparisons over time, across location, and across risks. Because the entire time series from 1990 to 2019 has been re-estimated with use of consistent data and methods, these results supersede previously published GBD estimates of attributable burden. Findings: The largest declines in risk exposure from 2010 to 2019 were among a set of risks that are strongly linked to social and economic development, including household air pollution; unsafe water, sanitation, and handwashing; and child growth failure. Global declines also occurred for tobacco smoking and lead exposure. The largest increases in risk exposure were for ambient particulate matter pollution, drug use, high fasting plasma glucose, and high body-mass index. In 2019, the leading Level 2 risk factor globally for attributable deaths was high systolic blood pressure, which accounted for 10·8 million (95 uncertainty interval UI 9·51–12·1) deaths (19·2% 16·9–21·3 of all deaths in 2019), followed by tobacco (smoked, second-hand, and chewing), which accounted for 8·71 million (8·12–9·31) deaths (15·4% 14·6–16·2 of all deaths in 2019). The leading Level 2 risk factor for attributable DALYs globally in 2019 was child and maternal malnutrition, which largely affects health in the youngest age groups and accounted for 295 million (253–350) DALYs (11·6% 10·3–13·1 of all global DALYs that year). The risk factor burden varied considerably in 2019 between age groups and locations. Among children aged 0–9 years, the three leading detailed risk factors for attributable DALYs were all related to malnutrition. Iron deficiency was the leading risk factor for those aged 10–24 years, alcohol use for those aged 25–49 years, and high systolic blood pressure for those aged 50–74 years and 75 years and older. Interpretation: Overall, the record for reducing exposure to harmful risks over the past three decades is poor. Success with reducing smoking and lead exposure through regulatory policy might point the way for a stronger role for public policy on other risks in addition to continued efforts to provide information on risk factor harm to the general public. Funding: Bill & Melinda Gates Foundation. © 2020 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 licens
Anemia prevalence in women of reproductive age in low- and middle-income countries between 2000 and 2018
No full textAnemia is a globally widespread condition in women and is associated with reduced economic productivity and increased mortality worldwide. Here we map annual 2000–2018 geospatial estimates of anemia prevalence in women of reproductive age (15–49 years) across 82 low- and middle-income countries (LMICs), stratify anemia by severity and aggregate results to policy-relevant administrative and national levels. Additionally, we provide subnational disparity analyses to provide a comprehensive overview of anemia prevalence inequalities within these countries and predict progress toward the World Health Organization’s Global Nutrition Target (WHO GNT) to reduce anemia by half by 2030. Our results demonstrate widespread moderate improvements in overall anemia prevalence but identify only three LMICs with a high probability of achieving the WHO GNT by 2030 at a national scale, and no LMIC is expected to achieve the target in all their subnational administrative units. Our maps show where large within-country disparities occur, as well as areas likely to fall short of the WHO GNT, offering precision public health tools so that adequate resource allocation and subsequent interventions can be targeted to the most vulnerable populations
Sparsentan in patients with IgA nephropathy: a prespecified interim analysis from a randomised, double-blind, active-controlled clinical trial
No full textBackground: Sparsentan is a novel, non-immunosuppressive, single-molecule, dual endothelin and angiotensin receptor antagonist being examined in an ongoing phase 3 trial in adults with IgA nephropathy. We report the prespecified interim analysis of the primary proteinuria efficacy endpoint, and safety. Methods: PROTECT is an international, randomised, double-blind, active-controlled study, being conducted in 134 clinical practice sites in 18 countries. The study examines sparsentan versus irbesartan in adults (aged ≥18 years) with biopsy-proven IgA nephropathy and proteinuria of 1·0 g/day or higher despite maximised renin-angiotensin system inhibitor treatment for at least 12 weeks. Participants were randomly assigned in a 1:1 ratio to receive sparsentan 400 mg once daily or irbesartan 300 mg once daily, stratified by estimated glomerular filtration rate at screening (30 to 1·75 g/day). The primary efficacy endpoint was change from baseline to week 36 in urine protein-creatinine ratio based on a 24-h urine sample, assessed using mixed model repeated measures. Treatment-emergent adverse events (TEAEs) were safety endpoints. All endpoints were examined in all participants who received at least one dose of randomised treatment. The study is ongoing and is registered with ClinicalTrials.gov, NCT03762850. Findings: Between Dec 20, 2018, and May 26, 2021, 404 participants were randomly assigned to sparsentan (n=202) or irbesartan (n=202) and received treatment. At week 36, the geometric least squares mean percent change from baseline in urine protein-creatinine ratio was statistically significantly greater in the sparsentan group (-49·8%) than the irbesartan group (-15·1%), resulting in a between-group relative reduction of 41% (least squares mean ratio=0·59; 95% CI 0·51-0·69; p<0·0001). TEAEs with sparsentan were similar to irbesartan. There were no cases of severe oedema, heart failure, hepatotoxicity, or oedema-related discontinuations. Bodyweight changes from baseline were not different between the sparsentan and irbesartan groups. Interpretation: Once-daily treatment with sparsentan produced meaningful reduction in proteinuria compared with irbesartan in adults with IgA nephropathy. Safety of sparsentan was similar to irbesartan. Future analyses after completion of the 2-year double-blind period will show whether these beneficial effects translate into a long-term nephroprotective potential of sparsentan. Funding: Travere Therapeutics
