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Pyrrolidine synthesis via ring contraction of pyridines
Modelling Temperature-dependent Schistosomiasis Dynamics for Single and Co-infections with S. mansoni and S. haematobium
Schistosomiasis, a prevalent public health issue specifically in sub-Saharan Africa, is primarily attributed to Schistosoma haematobium and Schistosoma mansoni, often occurring concurrently. These schistosome species share similarities in life cycles and transmission, manifesting comparable infection patterns and susceptibility to temperature variations. This study investigates the influence of temperature control not only on the transmission of individual species but also on their mutual interactions and co-infection dynamics using a mathematical model. Sub-models and co-dynamic properties, including reproduction numbers, equilibrium states, and stability conditions, are derived. Sensitivity analysis is performed to clarify the impact of parameter variations on model stability. Results suggest that temperature variation increases the spread of S. haematobium, which enhances susceptibility to S. mansoni co-infection, possibly by altering the immune response. At moderate temperatures (20°C and 25°C), infection levels in both single and co-infected individuals are higher, while recovery rates increase with temperature, peaking at 25°C and 35°C as infections significantly decrease. Biomphalaria snails exhibit greater population growth and susceptibility to infection than Bulinus snails, particularly below 25°C. Above this temperature, Biomphalaria population decreases while Bulinus species are more likely to experience faster mortality. These temperature-related variations differently impact mortality rates of intermediate snails and snail-to-human transmissibility rates for schistosome species, holding significant health implications. Targeting snails during seasons below 25°C, when susceptibility is higher, and intensifying human treatment interventions around 25°C–35°C, where recovery rates peak, may yield optimal results, particularly during seasons with intermediate temperatures around 25°C for both snails and humans. The results underscore the importance of integrating temperature into models for predicting and managing schistosomiasis dynamics for both genera. Therefore, this model is applicable not only to sub-Saharan Africa, but also to other regions where the described temperature ranges match with the local climate.
An interpretable dimensional reduction technique with an explainable model for detecting attacks in Internet of Medical Things devices
Discovery of mammalian collagens I and III within ancient poriferan biopolymer spongin
Abstract Spongin is a fundamental biopolymer that has played a crucial role in the skeletogenesis of keratosan sponges for over 800 million years. This biomaterial had so far remained chemically unidentified and believed to be an enigmatic type of halogenated collagen-keratin-based bioelastomer. Here we show collagen I and III as the main structural components of spongin. Proteomics, 13C solid state NMR and Raman spectroscopy confirm the identity of collagenous domains in spongin with collagen from mammals. Using an HPLC-MS analysis, we found halogenated di- and tri-tyrosines as crosslinking agents in spongin. Using molecular dynamics modeling, we solvated the crystal structures of collagen mimetic peptides for type I and type III collagens in four different systems, including selected brominated crosslinks. The results underscore the complex interplay between the collagen structures and crosslinks, raising intriguing questions about the molecular mechanisms underlying collagen chemistry within spongin as an ancient biocomposite.
Revisiting the physical limits to economic growth, with a focus on the waste heat limit
Whether there are imminent physical limits to economic growth has been the focus of a long-standing debate, often (but not exclusively) pitting natural scientists against economists. One side of the debate posits that finite resources constrain human economic growth, the other that productivity improvements and substitution can relax those resource constraints. However, the two sides lack a common framework to resolve their disagreement. We provide this framework and mediate this dispute using a combination of low-order economic and physical models, focusing especially on the waste heat limit. To start, we use a simple accounting identity to show that historical rates of growth in average productivity can support modest economic and population growth (totaling 1.2%). We model the future trajectory of productivity growth by combining a canonical production function (Cobb-Douglas) with a flexible model where population growth drives total-factor-productivity growth. We find remarkable parameter sensitivity: across a plausible range of parameters waste heat either never constrains economic growth in the model or does so in a few hundred years. Interestingly, either decreasing or increasing population growth can dramatically extend the time to heat constraint in the model, the latter due to increases in innovation. Finally, we use a more flexible (constant elasticity of substitution) production function and historical changes in the relative use of different resources to show that humans have the ability to substitute away from resources in shorter supply. Although there are vast uncertainties in this type of projection, our work highlights the potential for an optimistic future for humanity in which economic growth continues on a millennial timescale.
Daidzein alleviates skin fibrosis by suppressing TGF-β1 signaling pathway via targeting PKM2
An operating system for executing applications on quantum network nodes
A skin organoid-based infection platform identifies an inhibitor specific for HFMD
Determining cost-saving risk thresholds for statin use
Background The German government has recently drafted a bill proposing a reduction in the prescription threshold for statin use. This study aims to determine the cost-saving risk threshold for statin use in Germany to inform this proposed change. Methods An economic evaluation utilizing a decision-analytic model was performed, using secondary data to compare statin use versus no statin use from the perspective of German sickness fund insurees. The analysis focused on cost savings from avoided cardiovascular (CV) events, translating these avoided events into net savings after accounting for treatment costs and potential side effects. The study considered the German adult population insured by sickness funds and used a lifetime horizon for the analysis. Results The maximum number needed to treat (NNT) to achieve cost savings over 10 years was found to be 39, leading to a minimum CV risk threshold for savings of 10.2%. It was estimated that approximately 19% of the adult population in Germany has a 10-year CV risk of ≥ 10.2%, potentially avoiding between 271,739 and 581,363 CV events over 10 years, with net population savings of approximately €15 billion. Conclusions A threshold for statin prescription in Germany set at a 10.2% 10-year CV risk could significantly increase the number of patients benefiting from statin therapy, reducing CV events and generating substantial cost savings. These findings suggest that adjustments to prescription guidelines could improve cardiovascular outcomes and economic efficiency within the German healthcare system.
Effect of basalt fiber content on mechanical properties of hydrophobic mortar
Community estimate of global glacier mass changes from 2000 to 2023
Abstract Glaciers are indicators of ongoing anthropogenic climate change1. Their melting leads to increased local geohazards2, and impacts marine3 and terrestrial4,5 ecosystems, regional freshwater resources6, and both global water and energy cycles7,8. Together with the Greenland and Antarctic ice sheets, glaciers are essential drivers of present9,10 and future11–13 sea-level rise. Previous assessments of global glacier mass changes have been hampered by spatial and temporal limitations and the heterogeneity of existing data series14–16. Here we show in an intercomparison exercise that glaciers worldwide lost 273 ± 16 gigatonnes in mass annually from 2000 to 2023, with an increase of 36 ± 10% from the first (2000–2011) to the second (2012–2023) half of the period. Since 2000, glaciers have lost between 2% and 39% of their ice regionally and about 5% globally. Glacier mass loss is about 18% larger than the loss from the Greenland Ice Sheet and more than twice that from the Antarctic Ice Sheet17. Our results arise from a scientific community effort to collect, homogenize, combine and analyse glacier mass changes from in situ and remote-sensing observations. Although our estimates are in agreement with findings from previous assessments14–16 at a global scale, we found some large regional deviations owing to systematic differences among observation methods. Our results provide a refined baseline for better understanding observational differences and for calibrating model ensembles12,16,18, which will help to narrow projection uncertainty for the twenty-first century11,12,18.
Author Correction: Segregation-dislocation self-organized structures ductilize a work-hardened medium entropy alloy
Spatio-temporal evolution of habitat quality and its influencing factors in karst areas based on the InVEST model
The Critical Karst Zone provides rich natural resources and is an important habitat for the survival and development of the world’s human population. Meanwhile, urbanization processes have disrupted the structure and function of natural ecosystems, endangering biodiversity and habitats. However, existing studies have few frequently explored the combined effects of the natural environment and human activities on changes in habitat quality. This article uses the InVEST model and the GeoDetector method to analyze the changes in landscape patterns, spatiotemporal evolution of habitat quality, and their driving factors in karst areas. The results show that: (i) From 1990 to 2020, forest, cropland, and grassland fluctuated sharply, while the building and waters area showed an exponential upward trend. The overall landscape fragmentation and spatial heterogeneity are enhanced. (ii) The karst habitat quality index decreased from 0.7751 to 0.74085, showing an overall downward trend. The habitat quality shows a spatial distribution pattern of “high in the surrounding areas and low in the central areas”, and autocorrelation analysis shows that county-level units have significant spatial agglomeration effects. (iii) The overall type shows an enhancement of dual factor or non-linear, in which land use intensity and population density are the main driving factors for the spatio-temporal evolution of habitat quality. In summary, adopting stringent ecological protection and restoration initiatives aimed at minimizing human activity intensity and safeguarding natural habitat integrity in karst regions is imperative. Such measures contribute to the scientific underpinning for decision-making regarding the optimization of regional landscape composition and enhance land spatial planning strategies.