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Fundamental limitations of shoreline models
Get PDFDespite widespread use, many shoreline models rely on foundational assumptions that introduce significant uncertainties in coastal predictions and associated management decisions. As climate change intensifies risks to vulnerable coastal systems, it is imperative to strengthen efforts toward developing more robust and context-appropriate modelling approaches that reflect the evolving dynamics of coastal systems
Making progress with newborn screening
Get PDFReport from an event held in conjunction with Cambridge Prisms: Precision Medicine
Revisionism in logic
No full textPeirce usefully distinguished between logica utens, the rules implicitly followed by competent deductive reasoners, and the logica docens of the theorist. Revisions to logica docens are commonplace and philosophically unproblematic but modern theories are no longer even a plausible codification of logica utens. An individual can certainly revise the rules he goes by in deduction, but the question then arises whether such revisions imply a change in the meaning of the pertinent connectives. Quine and Dummett both held that the meaning would always change in such a case but their arguments are unconvincing. Following Putnam and others, I argue that acceptance of certain widely employed inferential principles is implicit in using logical vocabulary in its standard sense, while acceptance of other principles is not. The test is whether the soundness of the relevant principles follows (using our best logic) from general semantic axioms which specify the senses of logical vocabulary even in its non-deductive uses. In this way, I answer the charge of arbitrariness which is frequently laid against any view on which some, but not all, logical principles are latent in the senses of the connectives
Navigating severe class imbalance in population cohort data
Get PDFClass imbalance is a major challenge in predictive modelling for rare disease outcomes, particularly in large-scale population cohorts. Traditional machine learning models often struggle with imbalanced datasets, leading to biased performance metrics and poor generalisability. This study systematically evaluates multiple approaches to mitigate class imbalance in predicting Multiple myeloma using proteomic and clinical data from UK Biobank. We compare standard classification models (XGBoost and logistic regression) with synthetic resampling (SMOTE), anomaly detection techniques (isolation forests, local outlier factors, one-class SVM, and autoencoders), and a transformer-based foundation model (TabPFN), using standard classification performance metrics. Our results indicate that anomaly detection models generalise better than conventional classifiers (XGBoost and logistic regression), while SMOTE fails to improve, and may actively worsen, predictive performance. To address the precision-sensitivity trade-off, we introduce a sequential XGBoost ensemble classifier (SeqXGB) that prioritises high precision over sensitivity to minimise false positive predictions. Compared with a single XGBoost model, the SeqXGB approach successfully reduces false positives (420 vs 9), but significantly limits sensitivity (0.70 vs 0.15) in held-out test data. Our findings highlight that no single method is universally optimal for addressing class imbalance; rather, model selection should be guided by clinical application, balancing the risks of false positives and false negatives
Higher vitamin K1 intakes are associated with lower subclinical atherosclerosis and lower risk for atherosclerotic vascular disease-related outcomes in older women
Get PDFPurpose: Vitamin K may inhibit vascular calcification, a common attribute of atherosclerotic vascular diseases (ASVDs). We examined associations between dietary vitamin K1 intakes and both subclinical atherosclerosis and ASVD events, including hospitalisations and mortality, in older women. Methods: 1,436 community-dwelling women (mean ± SD age 75.1 ± 2.7 years) were included. Vitamin K1 intakes were calculated from a validated food frequency questionnaire at baseline (1998), utilising a region-matched vitamin K food database. Common carotid artery intima–media thickness (CCA-IMT), a measure of subclinical atherosclerosis, was measured in 2001 (n = 1,090). Differences in CCA-IMT by quartiles (Q) of vitamin K1 intake were examined using multivariate analysis of variance. Associations between vitamin K1 intakes and ASVD outcomes (hospitalisations and/or deaths), obtained from linked health records over 14.5 years, were analysed using restricted cubic splines within multivariable-adjusted Cox-proportional hazard models. Results: Women with higher vitamin K1 intakes had a 5.6% lower mean CCA-IMT (Q4 [median 119 µg/day] compared to Q1 [median 49 µg/day], p < 0.001). Over 14.5 years, 620 (43.1%), 497 (34.6%) and 301 (20.9%) ASVD events, hospitalisations, and deaths were recorded, respectively. In multivariable-adjusted models, the highest vitamin K1 intakes (Q4, compared to Q1), were associated with lower relative hazards for ASVD events (HR 0.71 95%CI 0.55–0.92) and ASVD mortality (HR 0.57 95%CI 0.40–0.83), but not ASVD hospitalisations (HR 0.83 95%CI 0.63–1.11). Conclusion: Vitamin K1 intakes of ~ 120 µg/day appear to be beneficial in lowering risk for subclinical and clinical ASVD in older women. These quantities can be attained by consuming vitamin K1 rich foods, such as leafy green vegetables
Management approach matters: meeting seagrass recovery and carbon mitigation goals
Get PDFSeagrass habitats support biodiversity, improve water quality, protect coastlines, and sequester carbon, among other essential ecosystem functions, yet they are declining worldwide due to human activity. Seagrass restoration and conservation can act as nature-based solutions for climate change, garnering growing interest from a diversity of stakeholders globally. Despite this interest, no seagrass projects have yet received carbon credits under international voluntary carbon standards. There is a clear need to better understand potential carbon mitigation outcomes of seagrass conservation and restoration practices. Here, we developed a mechanistic model based on a temperate meadow of Zostera marina to estimate carbon benefits (including net carbon dioxide removals, reductions, and methane and nitrous oxide fluxes) over 10 years as a result of four theoretical seagrass management scenarios, selected for their prevalence and potential—(1) restoration via seeding, (2) restoration via transplanting, (3) conserving a meadow and associated sediment from loss (e.g., from dredging), and (4) infilling an area with sediment prior to transplanting. We found significant differences and high variability in carbon benefits between these management scenarios. Restoration via transplant led to higher carbon gains than restoration via seeding, driven by more rapid areal bed expansion in transplanted meadows. However, the infill (adding 1 m of sediment) and conservation (preventing loss of 1 m of sediment) scenarios had total carbon benefits roughly 13–33 times (respectively) higher than the seeding and transplanting scenarios in which no sediment was mobilized. Within the model presented here, the minimum estimated revenue shows a 6 Ha seeding project generating as little as 1.53 million over this same time period (21,910 ± 2196 T CO2eq), excluding costs for project implementation and MRV (monitoring, reporting and verification). Voluntary carbon credit revenue variability (ranging from 15,337 per Ha) is driven by project size, project approach, and carbon price, among other factors. This work highlights the need for careful, context-specific consideration for if and how carbon finance might support seagrass recovery goals. Seascape-level approaches that pair strategic sediment management and avoided emissions with habitat restoration may lead to the highest climate mitigation benefits, while simultaneously supporting biodiversity and other ecosystem functions
Prediction models for maternal and offspring short- and long-term outcomes following gestational diabetes: a systematic review
Get PDFObjectives: Gestational diabetes mellitus (GDM), affecting one in seven pregnant women worldwide, can have short- and long-term adverse outcomes for both the mother and her baby. Despite a raft of prognostic models aiming to predict adverse GDM outcomes, very few have impacted clinical practice. This systematic review summarizes and critically evaluates prediction models for GDM outcomes, to identify promising models for further evaluation.
Methods: We searched EMBASE, MEDLINE, Web of Science, CINAHL, and CENTRAL for studies that reported the development or validation of predictive models for GDM outcomes in mother or offspring (PROSPERO: CRD42023396697).
Results: Sixty-four articles detailing 103 developed and 12 validated models were included in this review. Of these, 45% predicted long term, 31% birth, and 23% pregnancy outcomes. Most models (87%) had a high risk of bias, lacking sufficient outcome events, internal validation, or proper calibration. Only eight models were found at low risk of bias.
Conclusions: Our findings highlight a gap in rigorously developed prediction models for adverse GDM outcomes. There is a need to further validate existing models and evaluate their clinical utility to generate risk prediction tools capable of improving clinical decision-making for women with GDM and their children
International mobility and world development: estimating the system-level impact of ECA and international exchanges
Get PDFIn an era marked by increasingly restrictive mobility policies in major host countries, this report provides the first comprehensive, global assessment of whether and how U.S.-sponsored international exchange contributes to societal development. Commissioned by the U.S. Department of State, it examines the systemic effects of educational and professional mobility programs administered by the Bureau of Educational and Cultural Affairs (ECA). Drawing on a unique mixed-methods design, the study integrates quantitative findings from a longitudinal dataset of 134 countries with qualitative insights from 704 interviews in 70 countries across Sub-Saharan Africa (AF), East Asia and the Pacific (EAP), Europe and Eurasia (EUR), the Near East (NEA), South and Central Asia (SCA), and the Western Hemisphere (WHA). In doing so, it not only presents an unprecedented empirical breadth but also underscores how transnational dimensions of mobility—emerging from international mobility experiences—spark transformative learning processes, thereby embedding global experiences in local contexts. By advancing an evidence-based understanding of if and how internationally mobile alumni adapt what they learn abroad to generate systemic change at home, this first-of-its-kind investigation proposes clear directions for policy and research.
The research design combines breadth and depth by blending robust quantitative and qualitative methods. Quantitatively, the study employs a longitudinal dataset covering eight decades of ECA alumni participation, enabling advanced statistical models—such as multilevel random slope techniques—to account for country-specific variations over time. These analyses provide compelling evidence of the association between international mobility and societal outcomes. Qualitatively, 704 semi-structured interviews enrich the quantitative findings by illustrating how alumni adapt or rework external knowledge to suit local conditions, negotiate obstacles, and build and sustain the transnational linkages needed to drive systemic reforms. By focusing on enduring connections and learning that arise from transnational mobility, the study provides a framework for capturing both global patterns and specific ways mobility shapes local contexts. By systematically integrating new theoretical perspectives—especially those that illuminate how individual agents navigate structural, cultural, and relational factors—the report offers innovative insights into how global engagement becomes embedded in local institutions and practices.
The research confirms a robust association between higher concentrations of ECA alumni and moderate but significant improvements in economic growth, population health, educational access, gender equity, and democratic development. Although the correlation does not establish causation, the associations hold when accounting for factors like GDP per capita, tertiary enrolment rates, and international trade. The quantitative data suggest that participants trained in the U.S., as opposed to those studying in less open environments, demonstrate clearer patterns of alignment with positive home-country outcomes—likely due to more flexible academic settings, stronger transnational social relations, and normative frameworks that support civic engagement.
Qualitative interviews shed light on four mutually reinforcing mechanisms by which alumni translate overseas experiences into local reforms. First, they enhance their agency, the capacity to identify systemic problems, prioritize solutions, and persist amid challenges. Second, they gain advanced knowledge and skills, ranging from technical competencies to policy insights and civic understanding, which they can apply to upgrade local institutions or pilot innovative solutions in areas such as public health and economic development. Third, they develop intercultural competence, sharpening their ability to navigate cultural differences, empathize with multiple perspectives, and negotiate reforms in sensitive local contexts. Fourth, they cultivate long-term social relations that continue well beyond their stay abroad, with many alumni drawing on peer or mentor networks for the resources and collaborative partnerships needed to enact policy innovations or community-level interventions. These mechanisms unfold in local contexts shaped by varied governance structures, cultural expectations, and resource constraints. Although some alumni encounter obstacles such as gender discrimination and entrenched conservatism, others benefit from inclusive communities, viable funding, and political endorsement, which increase the odds of translating new ideas into durable institutional change.
Based on these findings, the report offers detailed policy recommendations to strengthen ECA programs as catalysts for systemic transformation. First, it calls for positioning ECA initiatives more explicitly as engines of deeper institutional reforms that align with both U.S. foreign policy priorities and global development goals, emphasizing robust metrics to document long-term effects and clearer narratives linking ECA outcomes to Sustainable Development Goals. Second, it encourages strategic integration of scholarships into broader development frameworks, including through partnerships with USAID and alignment with host-country needs, so that alumni-driven innovations can complement long-term capacity-building efforts in areas like education, governance, and public health. Third, it highlights the need to cultivate individual agency by scaling reflexive learning opportunities and broadening community engagement in both the U.S. and home countries. Fourth, it addresses the structural barriers alumni face, urging new or expanded initiatives to combat gender discrimination, navigate resistance to change, simplify bureaucratic processes, and secure sustainable funding. Equally important are measures to fortify community-based partnerships, so that local stakeholders are invested in implementing and sustaining changes triggered by returning participants. By advancing equity and accessibility—particularly for marginalized groups—and strengthening evidence-based evaluations of program results, the report argues that ECA can deepen its developmental footprint worldwide.
These policy recommendations are best supported by further research on underexplored issues, including the dual contributions of alumni in both their home and host countries, the potential of hybrid or virtual mobility, and effective strategies for broadening access to overseas experiences. It also calls for deeper investigation into how host-country contexts shape alumni outcomes: while this study shows that participants in U.S.-based programs often achieve greater success in driving reforms, further research could pinpoint the host-institution practices and support structures most conducive to systemic change back home.
By clarifying how alumni leverage agency, advanced skills, intercultural fluency, and supportive social ties to enact reforms, the report demonstrates the utility of ECA-sponsored programs as critical vehicles for development. Even amid new barriers to international mobility, ECA alumni can function as a vital link for knowledge-sharing and innovation. By mapping the processes through which overseas experiences translate into domestic change, the study highlights how international mobility benefits not only individual participants but broader societal development. Overall, it provides a trailblazing theoretical and empirical framework—one that may guide policymakers, practitioners, and researchers in harnessing the full promise of global engagement for sustainable social transformation
The political ecology of decentralized forest management in Cameroon: case study of the Bimbia-Bonadikombo community forest
Get PDFDecentralized forest management promotes the transfer of forest management responsibilities, resources and decision-making power from the central government to other members of the state. These include regional and local tiers of government, the private sector, non-governmental organisations (NGOs) and community based organizations (CBOs). While decentralization theory has been in the development literature since the 1950s, it gained prominence in the biodiversity conservation community after the Rio Summit of 1992.
This study is executed within a political ecology framework. Thus it is attentive to relationships within and between proximate and remote actors concerned with the management of a natural resource. The study is situated within the human geography meta-framework, making it attentive to the historicized relationship between space, place and people. Human geography’s qualitative ontological and epistemological foundations make it suitable for understanding contemporary social phenomena. The study pays attention to the spatial and temporal processes that mediate nature-society relationships, noting that nature and society are not independent but are co-productions of the human imaginary.
Advocates of decentralized forestry argue that its participatory ethos assures higher levels of accountability, transparency and equity compared with initiatives managed by the central state at the local level. This study, based on its findings, argues that forestry programmes, managed by local people for local people, do not have intrinsic qualities that assure higher quality outcomes compared with centrally administered programmes. The study shows that the local sphere is embedded in the national and the global, thus actors at higher spatial scales also dictate the tune at the local sphere. The study argues that efficiency and equity are socially determined and are not scalar variables as presented by decentralization theory
Sub-second optical/near-infrared quasi-periodic oscillations from the black hole X-ray transient Swift J1727.8–1613
Get PDFWe report on the detection of optical/near-infrared (O-IR) quasi-periodic oscillations (QPOs) from the black hole (BH) X-ray transient Swift J1727.8–1613. We obtained three X-ray and O-IR high-time-resolution observations of the source during its intermediate state (2023 September 9, 15, and 17) using NICER, HAWK-I@VLT, HIPERCAM@GTC, and ULTRACAM@NTT. We clearly detected a QPO in the X-ray and O-IR bands during all three epochs. The QPO evolved, drifting from 1.4 Hz in the first epoch, up to 2.2 Hz in the second, and finally reaching 4.2 Hz in the third epoch. These are among the highest O-IR QPO frequencies detected for a BH X-ray transient. During the first two epochs, the X-ray and O-IR emission are correlated, with an optical lag (compared to the X-rays) varying from +70 to 0 ms. Finally, during the third epoch, we measured, for the first time, a lag of the band with respect to the band at the QPO frequency ( +10 ms). By estimating the variable O-IR SED we find that the emission is most likely non-thermal. Current state-of-the-art models can explain some of these properties, but neither the jet nor the hot flow model can easily explain the observed evolution of the QPOs. While this allowed us to put tight constraints on these components, more frequent coverage of the state transition with fast multiwavelength observations is still needed to fully understand the evolution of the disc/jet properties in BH low-mass X-ray binaries