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The dragon’s head or Athens’ sacrifice zone? Spatiotemporal disjuncture, logistical disruptions, and urban infrastructural justice in Piraeus port, Greece
No full textPiraeus Port is the biggest port in Greece and ranks among the world’s largest passenger ports. By drawing on four years of in-depth ethnographic research and a deep familiarity with the area, I aim to elucidate the paradoxical juxtaposition between the allure of prosperity and rapid growth, intricately interwoven with the expansion of port and logistical infrastructures, and the concurrent escalation of adverse consequences for human and nonhuman life in the urban landscape. Bringing together literature on logistics and sacrifice zones, I introduce the notion of spatiotemporal disjuncture, to shed light on the coexistence of divergent realities within a single locale, rooted in the deliberate obfuscation of everyday truths inherent to these evolving infrastructural spaces. I conclude by emphasizing the necessity of placing the concept of urban infrastructural justice at the forefront of contemporary urban scholarship, both as a theoretical framework and a political demand capable of addressing infrastructural inequities exacerbated by the logistical revolution of the twenty-first century and fostering a collective imagination for radically different urban futures within and beyond port cities
Wastewater surveillance for Salmonella Typhi and its association with seroincidence of enteric fever in Vellore, India
No full textBackground
Blood culture-based surveillance for typhoid fever has limited sensitivity, and operational challenges are encountered in resource-limited settings. Environmental surveillance targeting Salmonella Typhi (S. Typhi) shed in wastewater (WW), coupled with cross-sectional serosurveys of S. Typhi-specific antibodies estimating exposure to infection, emerges as a promising alternative.
Methods
We assessed the feasibility and effectiveness of wastewater (WW) and sero-surveillance for S. Typhi in Vellore, India, from May 2022 to April 2023. Monthly samples were collected from 40 sites in open drainage channels and processed using standardized protocols. DNA was extracted and analyzed via quantitative PCR for S. Typhi genes (ttr, tviB, staG) and the fecal biomarker HF183. Clinical cases of enteric fever were recorded from four major hospitals, and a cross-sectional serosurvey measured hemolysin E (HlyE) IgG levels in children under 15 years of age to estimate seroincidence.
Results
7.50% (39/520) of grab and 15.28% (79/517) Moore swabs were positive for all 3 S. Typhi genes. Moore swab positivity was significantly associated with HF183 (adjusted odds ratio (aOR): 3.08, 95% CI: 1.59–5.95) and upstream catchment population (aOR: 4.67, 1.97–11.04), and there was increased detection during monsoon season - membrane filtration (aOR: 2.99, 1.06–8.49), and Moore swab samples (aOR: 1.29, 0.60–2.79).
Only 11 blood culture-confirmed typhoid cases were documented over the study period. Estimated seroincidence was 10.4/100 person-years (py) (95% CI: 9.61 - 11.5/100 py). The number of S. Typhi positive samples at a site was associated with the estimated sero-incidence in the site catchment population (incidence rate ratios: 1.14 (1.07–1.23) and 1.10 (1.02–1.20) for grab and Moore swabs respectively.
Conclusions
These findings underscore the utility and effectiveness of alternate surveillance approaches to estimating the incidence of S. Typhi infection in resource-limited settings, offering valuable insights for public health interventions and disease monitoring strategies where conventional methods are challenging to implement
Exploring AI-in-the-making: sociomaterial genealogies of AI performativity
No full textRecent interest in artificial intelligence technologies has led to much discussion about what the age of AI portends for how we live and work. And specifically for the present discussion, what it means for agency. In offering our contributions to these considerations, we build on approaches to treat AI not as a “thing” but as phenomena in-the-making. Such a framing orients us to doings, to practices, to enactments, and consequential outcomes. These considerations of AI-in-the-making are inspired by agential realism, a theory that calls attention to performativity and accountability. Based on these ideas, we propose a sociomaterial genealogical approach that we suggest is well-suited for the study of AI-in-the-making. In so doing, we provide qualitative scholars with a way of orienting their inquiries toward the performativity of ongoing AI reconfigurations and sociomaterial accountabilities
Spatial lipidomics reveals sphingolipid metabolism as anti-fibrotic target in the liver
No full textBackground and aims
Steatotic liver disease (SLD), which encompasses various causes of fat accumulation in the liver, is a major cause of liver fibrosis. Understanding the specific mechanisms of lipotoxicity, dysregulated lipid metabolism, and the role of different hepatic cell types involved in fibrogenesis is crucial for therapy development.
Methods
We analysed liver tissue from SLD patients and 3 mouse models. We combined bulk/spatial lipidomics, transcriptomics, imaging mass cytometry (IMC) and analysis of published spatial and single-cell RNA sequencing (scRNA-seq) data to explore the metabolic microenvironment in fibrosis. Pharmacological inhibition of sphingolipid metabolism with myriocin, fumonisin B1, miglustat and D-PDMP was carried out in hepatic stellate cells (HSCs) and human precision cut liver slices (hPCLSs).
Results
Bulk lipidomics revealed increased glycosphingolipids, ether lipids and saturated phosphatidylcholines in fibrotic samples. Spatial lipidomics detected >40 lipid species enriched within fibrotic regions, notably sphingomyelin (SM) 34:1. Using bulk transcriptomics (mouse) and analysis of published spatial transcriptomics data (human) we found that sphingolipid metabolism was also dysregulated in fibrosis at transcriptome level, with increased gene expression for ceramide and glycosphingolipid synthesis. Analysis of human scRNA-seq data showed that sphingolipid-related genes were widely expressed in non-parenchymal cells. By integrating spatial lipidomics with IMC of hepatic cell markers, we found excellent spatial correlation between sphingolipids, such as SM(34:1), and myofibroblasts. Inhibiting sphingolipid metabolism resulted in anti-fibrotic effects in HSCs and hPCLSs.
Conclusions
Our spatial multi-omics approach suggests cell type-specific mechanisms of fibrogenesis involving sphingolipid metabolism. Importantly, sphingolipid metabolic pathways are modifiable targets, which may have potential as an anti-fibrotic therapeutic strategy
A disease-specific convergence of host and Epstein–Barr virus genetics in multiple sclerosis
No full textRecent sero-epidemiological studies have strengthened the hypothesis that Epstein–Barr virus (EBV) may be a causal factor in multiple sclerosis (MS). Given the complexity of the EBV–host interaction, various mechanisms may be responsible for the disease pathogenesis. Furthermore, it remains unclear whether this is a disease-specific process. Here, we showed that genes encoding EBV interactors are enriched in loci associated with MS but not with other diseases and in prioritized therapeutic targets. Analyses of MS blood and brain transcriptomes confirmed a dysregulation of MS-associated EBV interactors affecting the CD40 pathway. Such interactors were strongly enriched in binding sites for the EBV nuclear antigen 2 (EBNA2) viral transcriptional regulator, often in colocalization with CCCTC binding factor (CTCF) and RNA Polymerase II Subunit A (POLR2A). EBNA2 was expressed in the MS brain. The 1.2 EBNA2 allele downregulated the expression of the CD40 MS-associated gene analogously to the CD40 MS-risk variant. Finally, we showed that the 1.2 EBNA2 allele associates with the risk of MS. This study delineates how host and viral genetic variability converge in MS-specific pathogenetic mechanisms
Measuring muscle activation with the HRX-1 wrist manipulation robot
No full textA portable robotic system, such as the HRX-1 robot designed for neuromechanics and rehabilitation research, enables motor assessment and training across diverse settings including clinics, laboratories, and home environments. This study presents the findings of wrist muscle activation measurements conducted using the HRX-1 robot in conjunction with surface electromyography (sEMG) electrodes on a cohort of fifteen healthy participants. Participants were seated and instructed to resist and maintain wrist flexion and extension against torques applied to their hand by the robot. Muscle activation data were recorded using two 32-channel high-density surface EMG electrodes placed on the forearm to capture activity from the flexor and extensor muscle groups. The analysis focuses on identifying the number of active regions within the recorded muscle activations under each experimental
condition. As expected, flexor muscles were most active during wrist flexion and extensor muscles were most active during wrist extension. There was also no statistically significant change in the number of muscle regions active when torque was increased in each configuration
A COMSOL framework for predicting hydrogen embrittlement, Part II: Phase field fracture
No full textPrediction of hydrogen embrittlement requires a robust modelling approach and this will foster the safe adoption of hydrogen as a clean energy vector. A generalised computational model for hydrogen embrittlement is here presented, based on a phase field description of fracture. In combination with Part I of this work, which describes the process of hydrogen uptake and transport, this allows simulating a wide range of hydrogen transport and embrittlement phenomena. The material toughness is defined as a function of the hydrogen content and both elastic and elastic–plastic material behaviour are incorporated, enabling to capture both ductile and brittle fractures, and the transition from one to the other. The accumulation of hydrogen near a crack tip and subsequent embrittlement is numerically evaluated in a single-edge cracked plate, a boundary layer model and a 3D vessel case study, demonstrating the potential of the framework. Emphasis is placed on the numerical implementation, which is carried out in the finite element package COMSOL Multiphysics, and the models are made freely available
Image-based Artificial Intelligence-driven modelling for blank shape optimisation in sheet metal forming
No full textDesign for manufacturing is essential to fully exploit the potential of emerging materials and processing technologies. However, traditional trial-and-error optimisation often exhibits inferior performance in manufacturability-driven problems, particularly when handling complex shapes. Surrogate modelling and optimisation have been widely investigated for efficiently predicting simulation results and enhancing manufacturability. Nevertheless, existing methods are mostly constrained by fixed shape parameterisation schemes, limiting their flexibility and effectiveness. To overcome this limitation, this research develops a non-parametric optimisation framework, validated on a sheet metal forming case study, specifically the blank shape optimisation of a hot-stamped B-pillar. The framework integrates an auto-decoder, serving as a differentiable blank shape generator, a convolutional neural network (CNN)-powered surrogate model for manufacturability evaluation, and an Adam optimiser for automated shape optimisation. The surrogate model predicts thickness distributions from the signed distance fields (SDFs) of blank shapes, which are generated by the auto-decoder from latent vectors; based on the predictions, the optimiser iteratively updates the latent vectors to acquire a blank shape with optimised manufacturability. The proposed framework demonstrates superior performance in terms of the accuracy of thickness distribution prediction, the fidelity of blank shape generation, and the efficiency of blank shape optimisation
Probing the transient far-IR Sky with PRIMA
No full textThe time variable far-IR/millimeter-wave sky is largely unexplored. However, when PRIMA launches, next-generation ground-based cosmic microwave background (CMB) experiments, including Simons Observatory and CMB-S4, will be operating. These will survey large areas of the sky for transient millimeter sources as a byproduct of their observations, producing regular millimeter-transient alerts. The first results from the current experiments show that they can detect a wide variety of millimeter transients ranging from galactic stars to extragalactic sources associated with active galactic nucleus and other energetic phenomena, and moving solar system objects such as asteroids. These results, and theoretical predictions, indicate that future millimeter/submillimeter facilities will detect many kinds of transients, including flaring stars, protostars, gamma-ray bursts, tidal disruption events, neutron star mergers, fast blue optical transients, and supernovae. New classes of millimeter-variable may be uncovered by CMB experiments, and transient searches at other wavelengths, such as the optical Legacy Survey of Space and Time survey, will produce additional targets to follow up with PRIMA. Predicted rates for extragalactic millimeter transients to be detected by CMB experiments range from 10 s to 1000s of events over the lifetime of these projects. CMB-S4 is most relevant for PRIMA, producing ∼100 extragalactic transients per year. Galactic transients and variable sources will also be detected, but the most common galactic transients, flaring stars, operate on such short timescales that direct follow-up with PRIMA will not be feasible. Variable accretion rates in forming protostars, conversely, produce long-term brightness variations that will be ideal monitoring targets. The addition of mid- and far-IR data points for all these sources can determine much about their radiation mechanisms and underlying physics. PRIMA follow-up of representative examples of various millimeter-transient and variable sources will thus have a powerful impact on our understanding of a wide range of astrophysical phenomena