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Trade and domestic distortions: the case of informality
No full textWe examine the effects of international trade in the presence of a set of domestic distortions
giving rise to informality, a prevalent phenomenon in developing countries. In our quantitative
model, the informal sector arises from burdensome taxes and regulations that are imperfectly
enforced by the government. In equilibrium, smaller, less productive firms face fewer distortions
than larger, more productive ones, potentially leading to substantial misallocation. We show
that in settings with a large informal sector, the gains from trade are significantly amplified,
as reductions in trade barriers imply a reallocation of resources from initially less distorted to
more distorted firms. We confirm findings from earlier reduced-form studies that the informal
sector mitigates the impact of negative labor demand shocks on unemployment. Nonetheless, the
informal sector can exacerbate the adverse real income effects of economic downturns, amplifying
misallocation. Last, our research sheds light on the relationship between trade openness and
cross-firm wage inequality
Impact and cost-effectiveness of Neotree, a digital data capture and decision support tool designed to improve neonatal survival in Zimbabwe: an interrupted time series analysis and economic evaluation
No full textIntroduction: Many neonatal deaths are avoidable using existing low-cost evidence-based interventions. This study evaluated the effectiveness and cost-effectiveness of Neotree, a digital quality improvement tool combining data capture with education and clinical decision support, implemented in a Zimbabwean hospital.
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Methods: Neotree was implemented in Chinhoyi Provincial Hospital (CPH) in December 2020. Using data collected for all neonates admitted to CPH from March 2020 to October 2023, a single group interrupted time series analysis was conducted to estimate the impact of Neotree implementation. Subgroup analyses explored the impact in low birth weight (1.5–2.5 kg) neonates, a key group targeted by the intervention.
Activity-based costing and expenditure approaches estimated costs of developing and implementing Neotree in CPH from a provider perspective. Both total within-study costs and total costs at scale were estimated and used to derive cost per life saved, cost per life year saved and cost per healthy life year (HLY) gained.
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Results: Analysis suggests reduced overall mortality in the post-implementation period, though this difference was not statistically significant (RR: 0.877, 95% CI 0.541 to 1.423, p=0.596). This was primarily driven by reduced mortality among the low birth weight subgroup (RR: 0.356, 95% CI 0.127 to 1.002, p=0.051). Cost-effectiveness analysis based on an assumed mortality impact in this subgroup suggests a within-study cost of around 6.35 per HLY gained at scale, substantially below the range of potential cost-effectiveness thresholds considered for Zimbabwe (US 855).
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Conclusion: Neotree is a potentially low-cost and highly cost-effective digital quality improvement tool to improve newborn care, morbidity and survival, while also providing quality data. This study contributes to limited economic evidence of mHealth tools in low-income and middle-income settings
Epoxy-oxylipins direct monocyte fate in inflammatory resolution in humans
No full textThe role of cytochrome P450-derived epoxy-oxylipins and their metabolites in human inflammation and resolution is unknown. We report that epoxy-oxylipins are present in blood of healthy, male volunteers at baseline and following intradermal injection of UV-killed Escherichia coli, an experimental model of acute resolving inflammation. At the site of inflammation, cytochrome P450s and epoxide hydrolase (EH) isoforms, which catabolise oxylipins to corresponding diols, are differentially upregulated throughout the inflammatory response, as is the biosynthesis of epoxy-oxylipins. GSK2256294, a selective sEH inhibitor specifically elevates 12,13-EpOME and 14,15-EET. While inhibition of sEH hastens pain resolution, it has no effect on tissue heat, redness and swelling. GSK2256294, however, significantly reduces numbers of circulating intermediate monocytes that expand during inflammation. We find that 12,13-EpOME blocks the transition of classical to intermediate monocytes in a p38 MAPK-dependent manner, results that are recapitulated when blocking p38 MAPK in vitro and when administering the p38 MAPK inhibitor losmapimod in vivo to healthy volunteers. Furthermore, fewer intermediate monocytes are observed at the site of inflammation, accompanied by reduced tissue CD4 T cells. Hence, we have mapped the expression, activity and function of epoxy-oxylipins in human inflammation revealing new mechanisms of monocyte differentiation and resolution biology
Lymphocyte Activation Gene 3 Regulation of Profibrotic Cytokines and Type I Collagen Production in Patients With Systemic Sclerosis
No full textOBJECTIVE: Diffuse cutaneous systemic sclerosis (dcSSc) is characterized by skin and internal organ fibrosis. The regulatory aspects of the immune system involved in maintaining tolerance are still poorly understood in dcSSc. The late checkpoint inhibitory lymphocyte activation gene 3 (LAG-3) is implicated in T cell inhibition by interacting with its ligand, major histocompatibility complex class II. Its role in dcSSc has yet to be established. METHODS: Plasma soluble LAG-3 (sLAG-3) levels of 35 patients with dcSSc were compared with the levels of 20 healthy controls (HCs). Peripheral blood mononuclear cell (PBMC) samples from patients with dcSSc (n = 8) and HCs (n = 8) were analyzed by flow cytometry for the surface expression of LAG-3 on CD4+ and CD8+ T cells after CD3/CD28 stimulation. The dcSSc PBMCs were stimulated (anti-CD3/CD28), kept as monocultures, or cocultured with autologous dermal fibroblasts and treated with a LAG-3 agonistic antibody or isotype control. The supernatants were analyzed for proinflammatory cytokines, extracellular matrix proteins, and bioactive type I interferon (IFN). RESULTS: Patients with dcSSc had a two-fold decreased sLAG-3 level compared with HCs (P < 0.0001). Increased surface expression of LAG-3 was observed in activated CD4+ T cells and CD8+ T cells in patients with dcSSc compared to HC PBMCs. The LAG-3 agonistic antibody decreased IFNγ, interleukin-4, and tumor necrosis factor α levels in supernatants from PBMCs and dermal fibroblast cocultures. Furthermore, we observed decreased pro collagen, fibronectin, and IFNα/β bioactivity in the cocultures. CONCLUSION: LAG-3 is immunoregulatory in dcSSc, and a LAG-3 agonistic antibody is a potential treatment modality
Benchmarking variability in semantic segmentation in minimally invasive abdominal surgery
No full textPURPOSE: Anatomical identification during abdominal surgery is subjective given unclear boundaries of anatomical structures. Semantic segmentation of these structures relies on an accurate identification of the boundaries which carries an unknown uncertainty. Given its inherent subjectivity, it is important to assess annotation adequacy. This study aims to evaluate variability in anatomical structure identification and segmentation using MedSAM by surgical residents. METHODS: Images from the Dresden Surgical Anatomy Dataset and the Endoscapes2023 Dataset were semantically annotated by a group of surgery residents using MedSAM in the following classes: abdominal wall, colon, liver, small bowel, spleen, stomach and gallbladder. Each class had 3 to 4 sets of annotations. Inter-annotator variability was assessed through DSC, ICC, BIoU and using the Simultaneous Truth and Performance Level Estimation algorithm to obtain a consensus mask and by calculating Fleiss' kappa agreement between all annotations and reference. RESULTS: The study showed strong inter-annotator agreement among surgical residents, with DSC values of 0.84-0.95 and Fleiss' kappa between 0.85 and 0.91. Surface area reliability was good to excellent (ICC = 0.62-0.91), while boundary delineation showed lower reproducibility (BIoU = 0.092-0.157). STAPLE consensus masks confirmed consistent overall shape annotations despite variability in boundary precision. CONCLUSION: The study demonstrated low variability in the semantic segmentation of intraperitoneal organs in minimally invasive abdominal surgery, performed by surgical residents using MedSAM. While DSC and Fleiss' kappa values confirm strong inter-annotator agreement, the relatively low BIoU values point to challenges in boundary precision, especially for anatomically complex or variable structures. These results establish a benchmark for expanding annotation efforts to larger datasets and more detailed anatomical features
Associations of self- and informant-reported functional impairment with cognitive performance and incident dementia
No full textIntroduction: Functional impairment is central to dementia diagnosis, typically assessed through basic and instrumental activities of daily living (ADLs/IADLs) reported by participants or informants. However, it remains unclear which items and reporting sources best capture cognition-related functional impairment. / /
Methods: We analysed data from 1,050 adults aged ≥65 years in the English Longitudinal Study of Ageing Harmonised Cognitive Assessment Protocol. Self- and informant-reported ADL and IADL impairments were examined at overall and item levels. Associations with general and domain-specific cognition were estimated using linear regression, and with incident dementia over 6.7 years using Cox models, both adjusted for socioeconomic, lifestyle, and health factors. / /
Results: ADL and IADL impairment proportions were similar across self- and informant-reports, with modest concordance. Informant-reported, but not self-reported, impairments were consistently associated with poorer cognition across domains, particularly executive function (informant-reported ADL: β = –0.71 SD, 95% CI –0.89 to –0.53) and memory (informant-reported IADL: β = –0.46 SD, 95% CI –0.60 to –0.32), and higher dementia risk (ADL: HR = 3.13, 95% CI 1.23 to 7.96; IADL: HR = 5.00, 95% CI 2.40 to 10.43). The strongest associations were observed for managing money and tasks involving episodic or visuospatial memory, especially among individuals with intermediate education and when informants had higher education or daily contact. / /
Discussion: Informant-reported IADLs, particularly those involving financial management and memory, may be strong indicators of cognitive impairment and dementia risk. Emphasising these items and informant characteristics may improve population surveillance of dementia and inform outcome selection in preclinical dementia trials targeting early functional decline. These findings should be interpreted in the context of a population-based sample with attrition
Portfolio Optimisation under Transaction Costs with Recursive Preferences
No full textThe Merton investment-consumption problem is fundamental, both in the field of finance and
in stochastic control. An important extension of the problem adds transaction costs, which is highly
relevant from a financial perspective but also challenging from a control perspective because the solution
now involves singular control. A further significant extension takes us from additive utility to stochastic
differential utility (SDU), which allows time preferences and risk preferences to be disentangled.
In this paper, we study this extended version of the Merton problem with proportional transaction
costs and Epstein-Zin SDU. We fully characterise all parameter combinations for which the problem is
well posed (which may depend on the level of transaction costs) and provide a full verification argument
that relies on no additional technical assumptions and uses primal methods only.
Even in the special case of (additive) power utility, our arguments are significantly simpler, more
elegant and more far-reaching than the ones in the extant literature. This means that we can easily
analyse aspects of the problem which previously have been very challenging, including comparative
statics, boundary cases which heretofore have required separate treatment and the situation beyond
the small transaction cost regime. A key and novel idea is to parametrise consumption and the value
function in terms of the shadow fraction of wealth, which may be of much wider applicability
Multimodal Layer‐Crossing Interrogation of Brain Circuits Enabled by Microfluidic Axialtrodes
No full textModulating and recording neuronal activity are essential for probing brain function and developing therapies for neurological disorders. However, conventional flat‐end optical fibers—widely used for deep brain access—interact with neural tissue only at their distal tip, limiting spatial resolution across brain layers. To address this challenge, we introduce the microfluidic axialtrode, a flexible neural interface that exploits controlled angled cleaving of a thermally drawn multimaterial fiber to achieve axial redistribution of integrated electrodes and microfluidic channels. We demonstrate in vivo that this design enables spatially distributed optogenetics, multisite electrophysiological recording, and targeted drug delivery along the fiber's axis, allowing simultaneous interaction with multiple neuronal layers. The axial configuration increases the functional interface with brain tissue, while the soft polymer construction and reduced footprint significantly suppress the inflammatory response compared to conventional silica fibers. Integration with a 3D‐printed scaffold, fabricated from FDA‐approved biocompatible resin, provides mechanical stability and compatibility with standard experimental hardware. The monolithic integration of these features positions the axialtrode as a scalable and versatile platform for next‐generation neural interfacing
Disentangling the impacts of collective mobility of residents and non-residents on burglary levels
No full textThis study investigates how the collective mobility (including movement and visiting) of residents and non-residents affects neighbourhood burglary levels. While past research has linked mobility to urban crime, this study explores how these relationships vary across population groups and social contexts at the neighbourhood level. Using mobile phone GPS data, we distinguished between residents and non-residents based on daily movement patterns. We then measured their mobility within defined spatial and temporal units. An explainable machine learning method (XGBoost and SHAP) was used to assess how mobility patterns influence burglary in London’s LSOAs from 2020 to 2021. Results show that increased collective mobility is generally associated with higher burglary levels. Specifically, non-resident footfall and residents’ stay-at-home time have a stronger influence than other variables like residents’ travelled distance. The impact also varies across neighbourhoods and shifts during periods of COVID-19 restrictions and relaxations. These findings confirm the dynamic link between mobility and crime, highlighting the value of understanding population-specific patterns to inform more targeted policing strategies
Thriving against the odds through positive deviant behavior: technology adoption and entrepreneurship among dairy farmers in Addis Ababa and Oromia in Ethiopia
No full textPositive deviant (PD) farmers can be differentiated from the wider farming community by their inherent capacity to leverage farming innovations and technologies in addressing challenges faced in engaging in agricultural production. There is currently a limited body of literature on how positive deviance and entrepreneurial behavior allow some dairy farmers to develop strategies that enable them to cope better with and creatively overcome challenges faced by their peers. This study employed a positive deviance approach to identify innovative dairy farmers in urban and peri-urban areas of the Addis Ababa and Oromia administrative regions of Ethiopia. PD farmers were identified and selected through a descriptive study design, utilizing a purposive and snowball sampling approach based on the number of technologies adopted in a previous survey study and referrals from other farmers. Data were collected through key informant interviews and participant observation on selected farms. We observed that PD dairy farmers had adopted and/or modified a variety of technologies to overcome context-specific challenges faced, such as seasonal feed shortages exacerbated by climate change, reduced land size and availability of land for grazing and waste disposal, and restrictions on farming resulting from the development of urban areas. These technologies enabled farmers to improve feed production, manure disposal, breeding practices, the quality of livestock housing, and animal welfare and enabled them to control diseases and add value to milk production. This study underscores the important role that PD dairy farmers could play as social referents, not only for their peers in urban and peri-urban areas but also for policymakers, extension workers and academics who are interested in working with dairy farmers in co-identifying and co-developing solutions to challenges currently undermining the sustainability of the dairy sector in Ethiopia and beyond