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Editorial: Organizations between continuity and disruption – The organization and management of perpetual change in times of digitalization
No full textThe 1924 Bogotá tram strike: mobilization and organization at the dawn of the working class
No full textEl presente trabajo reconstruye la huelga del tranvía de Bogotá de 1924, buscando así comprender las formas organizativas y de movilización de un grupo de trabajadores en los albores de la clase obrera. Detallamos los antecedentes de la huelga, las razones de su estallido y la negociación que le puso fin, evidenciando así las formas de organización que los trabajadores construyeron para afrontar la lucha reivindicativa. También verificamos que el desarrollo del conflicto exponía aspectos de la cotidianidad laboral de los tranviarios.Este artigo reconstrói a greve dos bondes de Bogotá de 1924, buscando compreender as formas de organização e mobilização de um grupo de trabalhadores no alvorecer da classe operária. Detalhamos os antecedentes da greve, as razões de sua deflagração e a negociação que a encerrou, evidenciando as formas de organização que os trabalhadores construíram para enfrentar a luta por reivindicações. Também verificamos que o desenvolvimento do conflito expunha aspectos da vida cotidiana dos trabalhadores dos bondes.This paper examines the Bogotá tramway strike of 1924, aiming to understand how early workers organized and mobilized. It discusses the background of the strike, its causes, and the negotiations that ended it, highlighting the strategies workers employed to push their demands. Additionally, the study shows that the conflict’s progression revealed essential aspects of tramway workers’ daily work lives
Restricted insecticide application: a last mile control option for elimination of acute sleeping sickness and progressive control of African animal trypanosomiasis in South-Eastern Uganda
No full textBackground
Animal African trypanosomiasis (AAT) poses a significant impediment to livestock production and economic progress in sub-Saharan Africa. To reduce the burden of AAT in Uganda and contribute to the AAT progressive control pathway, there is a need to develop effective AAT and tsetse control measures. In this study, we assessed a combination of chemotherapy and Restricted Insecticide Application Protocol (RAP) as a last mile control option for the progressive control of AAT and acute sleeping sickness in south- eastern Uganda.
Methods
Cattle from fourteen AAT endemic villages in south-eastern Uganda were treated with two doses of diminazene acecurate 40 days apart and sprayed with deltamethrin once monthly for 6 months following chemotherapy. Both cattle and tsetse flies were screened for trypanosomes before and 6 months into the interventions using ITS1-PCR. Tsetse flies trapped per day per trap were counted and the apparent tsetse fly density [Flies/Trap/Day-FTD] determined and mapped. The effect of chemotherapy and RAP on (1) FTD and (2) trypanosome infection in both cattle and tsetse flies was determined using mixed effects regression models.
Results
RAP and chemotherapy were associated with significantly lower odds of trypanosome infections in cattle (OR = 0.43, 95% CI; 0.35–0.54) and tsetse flies (OR = 0.06, 95% CI; 0.03–0.10). RAP and chemotherapy reduced Trypanosoma species prevalence from 23.38% to 12.70% among cattle and 73.33% to 21.76% in tsetse flies. Additionally, treatment was significantly associated ( P = 0.04) with a reduction in FTD by 1.02. Unlike T. vivax , both T. congolense and T. brucei infections were reduced by RAP and chemotherapy. There was a single infection with Trypanosoma brucei rhodesiense detected in the cattle and none in tsetse flies.
Conclusion
Combination of RAP and chemotherapy offers promising approach to control AAT in endemic areas and can support last mile acute sleeping sickness elimination efforts when combined with other available tsetse and AAT control methods. A singular infection with T. b. rhodesiense indicates that there is still a risk of acute sleeping sickness resurgence in south-eastern Uganda unless tsetse and trypanosomiasis control and surveillance efforts are maintained
Transporting higher-order quadrature rules - Quasi-Monte Carlo points and sparse grids for mixture distributions
No full textIntegration against, and hence sampling from, high-dimensional probability distributions is of essential importance in many
application areas and has been an active research area for decades. One approach that has drawn increasing attention in
recent years has been the generation of samples from a target distribution Ptar using transport maps: if Ptar = T Pref is the
pushforward of an easily-sampled probability distribution Pref under the transport map T , then the application of T to Prefdistributed
samples yields Ptar-distributed samples. This paper proposes the application of transport maps not just to random
samples, but also to quasi-Monte Carlo points, higher-order nets, and sparse grids so that the transformed samples inherit the
original convergence rates that are often better than N−1/2, N being the number of samples/quadrature nodes. Our main result
is the derivation of an explicit transport map for the case that Ptar is a mixture of simple distributions, e.g. a Gaussian mixture,
in which case application of the transport map T requires the solution of an explicit ODE with closed-form right-hand side.
Mixture distributions are of particular applicability and interest since many methods proceed by first approximating Ptar by a
mixture and then sampling from that mixture (often using importance reweighting). Hence, this paper allows for the sampling
step to provide a better convergence rate than N−1/2 for all such methods
CACHE Challenge #3: Targeting the Nsp3 Macrodomain of SARS-CoV-2
No full textThe third Critical Assessment of Computational Hit-finding Experiments (CACHE) challenged computational teams to identify chemically novel ligands targeting the macrodomain 1 of SARS-CoV-2 Nsp3, a promising coronavirus drug target. Twenty-three groups deployed diverse design strategies to collectively select 1739 ligand candidates. While over 85% of the designed molecules were chemically novel, the best experimentally confirmed hits were structurally similar to previously published compounds. Confirming a trend observed in CACHE #1 and #2, two of the best-performing workflows used compounds selected by physics-based computational screening methods to train machine learning models able to rapidly screen large chemical libraries, while four others used exclusively physics-based approaches. Three pharmacophore searches and one fragment growing strategy were also part of the seven winning workflows. While active molecules discovered by CACHE #3 participants largely mimicked the adenine ring of the endogenous substrate, ADP-ribose, preserving the canonical chemotype commonly observed in previously reported Nsp3-Mac1 ligands, they still provide novel structure–activity relationship insights that may inform the development of future antivirals. Collectively, these results show that multiple molecular design strategies can efficiently converge on similar potent molecules
An endovascular porcine model of abdominal aortic aneurysm for interventional radiology research
No full textObjective
Abdominal aortic aneurysm (AAA) remains a life-threatening condition with few large-animal disease models. We aimed to develop a fully endovascular porcine AAA model for radiology research, reducing surgical trauma and improving reproducibility versus laparotomy-based models.
Materials and methods
Fourteen female German Landrace swine ( n = 14, 30–40 kg) underwent angiography-guided intervention. The animals’ infrarenal aorta was dilated by ~30% via balloon catheter, then collagenase (6,000 IU), elastase (500 IU), and 25% calcium chloride (0.5 mL) were locally incubated to weaken the vessel wall. Eight animals were included in the study; group 1 ( n = 4) was euthanized at 2 weeks, and group 2 ( n = 4) at 4 weeks. Aortic diameter was measured weekly by ultrasound; ex vivo histology, immunofluorescence, and western blot assessed remodeling and inflammation.
Results
Progressive aneurysm expansion was observed, with diameters of 1.32 ± 0.08 cm (mean ± standard deviation) at 1 week post-intervention, 1.59 ± 0.06 cm at 2 weeks, 1.81 ± 0.10 cm at 3 weeks, and 1.94 ± 0.19 cm at 4 weeks (baseline: 0.74 ± 0.08 cm; p < 0.001). Experimental groups’ macrophages increased (group 1, 15.12 ± 3.88%; group 2, 16.65 ± 5.27%) compared to control (0.66 ± 0.27%, p = 0.012 and p = 0.021, respectively). Vascular smooth muscle cells were reduced across interventional groups (45.97 ± 17.26% versus control 80.94 ± 14.26%, p = 0.005).
Conclusions
This porcine AAA model replicates human disease features with a fully endovascular workflow, offering a valuable platform for evaluation of novel imaging techniques and interventional therapies.
Relevance statement
This study presents a fully endovascular porcine model of abdominal aortic aneurysm for translational research in interventional radiology and imaging. By enabling aneurysm induction entirely through catheter-based techniques, the model could provide a clinically relevant platform for future evaluation of novel endovascular devices and intraluminal therapeutics.
Key Points
This study established a fully endovascular, translational porcine model of abdominal aortic aneurysm. The model exhibited a significant mean aneurysmal dilation of about 161% at 4 weeks and 107% at 2 weeks. Serial ultrasound confirmed consistent aneurysm expansion and reproducible growth patterns in surviving animals. Ex vivo analyses demonstrated inflammation and extracellular-matrix damage, mirroring key features of human abdominal aortic aneurysm pathology. This fully catheter-based workflow provides a practical preclinical platform for evaluating imaging techniques and endovascular therapies
Injured epithelial cell states impact kidney allograft survival after T-cell-mediated rejection
No full textT-cell–mediated rejection (TCMR) remains a major cause of kidney transplant failure, despite being considered treatable. Its impact reflects a limited understanding of the underlying molecular mechanisms and their clinical consequences. To address this, we induced acute TCMR in mouse kidney transplants and profiled molecular changes using single-nucleus RNA sequencing (snRNA-seq), spatial transcriptomics and immunofluorescence. Results were compared with human snRNA-seq data from TCMR and stable allografts, as well as single-cell deconvolution analysis of bulk transcriptomic data from kidney transplant biopsies. Here we show that TCMR induces injured epithelial cell states in mouse kidney allografts, particularly in proximal tubules and thick ascending limbs. Spatial transcriptomics of these injured epithelial states demonstrated heterogeneous localization, interactions with immune cells and cellular microenvironments. Cross-species analysis confirmed similar severely injured epithelial states in human samples, whose abundances correlated with transplant survival and persisted despite TCMR resolution. Collectively, our results identify epithelial injury cell states as a determinant of outcome after TCMR
The test of time: experimentally recreating the reanalysis of FINISH as a recent past marker
No full textIn grammaticalization studies, reanalysis is understood as the assignment of new meaning to formally unchanged elements, supported by bridging contexts compatible with the old and the reanalyzed meaning. The source determination hypothesis (SDH) predicts that parallel grammaticalization trajectories occur crosslinguistically, as similar source meanings give rise to similar inferences. One such pattern is the development of recent past markers from FINISH constructions. While grammaticalization pathways are well-documented crosslinguistically, the SDH has never been tested experimentally. In this study, we examine whether modern English speakers are sensitive to inferences arising from a bridging context identified as relevant to the grammaticalization of Old Spanish FINISH into a recent past marker. In a temporal distance judgment task, we examined whether the bridging context identified for Old Spanish facilitates an inference of temporal immediacy in contemporary English, where the construction has not been grammaticalized. In line with the SDH, the bridging context enhanced an inference of immediacy in contemporary English (Exp. 1), with specific grammatical features of the source determining its strength (Exp. 2). These results not only demonstrate the viability of testing hypotheses about language change using experimental pragmatics but also call for empirically refining the concept of source determination
A Chromosome-Level Genome Assembly and Resequencing Data Reveal Low DNA Methylation and Reduced Diversity in the Solitary Bee Pollinator Osmia cornuta
No full textBees provide essential pollination services that contribute to ecosystem stability, as well as the sustainability of economic crop yields. Due to concerns over global and local declines, improving our understanding of these ecologically and commercially important species is crucial for determining their capacity to respond and adapt to environmental challenges. The European orchard bee (Osmia cornuta) is a solitary bee of increasing agricultural importance due to its role in the pollination of fruit crops, yet lacks genomic resources. Using cost-effective Nanopore-only long-read sequencing, we report the first genome assembly for O. cornuta, spanning 647.56 Mb across 727 contigs (N50 = 3.94 Mb) at a high level of completeness (99.88% BUSCO complete). In line with the expected number of chromosomes in this species, 16 major scaffolds were assembled to chromosome level. Also, we provisionally investigated the epigenomic architecture of O. cornuta, finding low numbers of CG dinucleotides that were either 5′-methylated or 5′-hydroxymethylated, providing additional evidence for the limited role methylation plays in gene regulation in Hymenopterans. To generate improved gene annotations, we combined transcriptomic- and orthology-based approaches, leading to the prediction of 12,144 genes and 25,964 proteins, showing exceptionally high BUSCO completeness (99.64%). Lastly, through whole-genome resequencing of a representative dataset, we provisionally find patterns of reduced nucleotide diversity and lower recombination rates within O. cornuta compared to other bee species. Collectively, our study provides a novel insight into the genome architecture of a key pollinator, providing an important resource to facilitate further genomic studies
Intraplate Volcanism Driven by Slab‐Plume Interaction: Numerical Modeling and Its Application to the Eifel, Massif Central and Hainan Volcanic Areas
No full textIntraplate volcanism has long been linked to deep mantle plumes. However, recent studies showed that intraplate magmatism can originate from transition zone dynamics, where lower‐mantle plumes might be ponding, creating a Thermal Boundary Layer (TBL). Inspired by intraplate volcanoes in Eifel, Massif Central and Hainan that are distributed near tips of stagnant slabs imaged at transition zone depth, we hypothesize that subducted slabs might destabilize the TBL and trigger upper mantle plumes (secondary plumes), leading to intraplate volcanism. So far, the generation of such secondary plumes and the influence of slabs on plumes remain poorly understood. In this study, we perform 2D upper‐mantle geodynamic models with a TBL imposed at 670 km depth interacting with a slab of an intra‐oceanic subduction zone. The effects of various slab geometries (rollback, rollover and intermediate), TBL temperature and heating time are tested. Our models show that slabs of all geometries can destabilize the TBL, initiating secondary plumes ahead of and behind the slab. All plumes are deflected by the slab‐induced mantle flow and a sinking slab may even suppress plumes beneath it. However, a higher TBL temperature and a longer pre‐subduction heating duration may increase buoyancy flux of secondary plumes, making them more resistant to slab‐driven flow. Under all conditions explored in this study, the strength of secondary plumes produced in our models is comparable to that of the Eifel plume. This paper elucidates slab‐plume interaction and their impact on intraplate volcanism with applications to the Eifel, Massif Central and Hainan volcanic areas