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The growing concern about future challenges of energy security and climate change has led to the expansion of renewable energy production, with a special emphasis on wind power. Despite the environmental advantages of wind power, it's important to assess the impacts caused by the presence of wind farms on wildlife, particularly on species also affected by habitat loss and degradation. In Mediterranean Europe, the skylark (Alauda arvensis) is a declining passerine that breeds in mountain habitats vulnerable to the abandonment of traditional management practices and climate change. We have created a spatially explicit agent-based model (ABM) in order to replicate the selection of territories, evaluating the effect of wind farms on the mortality rate of breeding males. We were especially interested in assessing the mortality rates related with the interplay between habitat loss due to socio-ecological change and increasing wind power using alternative strategies: adding wind turbines or substituting existing wind turbines by more powerful ones, i.e. repowering. Several known aspects related with the risk of collision of A. arvensis with wind turbines were considered, particularly regarding the male habitat selection and behaviour displayed throughout the breeding season. By simulating a sequential contraction of suitable habitat for the species, we found a substantial increase in the breeding territories superimposed to the wind farm influence zone. In these conditions males' relative mortality was predicted to suffer significant increases. For equivalent wind power, adding wind turbines produced significant increases in the males' relative mortality, whereas repowering didn't. Based on our findings we propose repowering as a defensible strategy to increase wind energy production without increasing A. arvensis collision risk. We highlight that this strategy might also benefit other vulnerable bird and bat species associated with declining habitats of mountain ridges in the Mediterranean region.
Assuntos
Ecossistema , Centrais Elétricas , Ecologia , Europa (Continente) , Energia RenovávelRESUMO
As of August 2022, the COVID-19 pandemic has accounted for over six million deaths globally. The urban population has been severely affected by this viral pandemic and the ensuing lockdowns, resulting in increased poverty and inequality, slowed economic growth, and a general decline in quality of life. This paper proposes a framework to evaluate the effects of the pandemic by combining agent-based simulations-based on Susceptible-Infectious-Recovered (SIR) model-with a hybrid neural network. A baseline agent-based model (ABM) incorporating various epidemiological parameters of a viral pandemic was developed, followed by an additional functional layer that integrates factors like agent mobility restrictions and isolation. It is inferred from the results that low population densities of agents and high restrictions on agent mobility could inhibit the rapid spread of the pandemic. This framework also envisages a hybrid neural network that combines the layers of convolutional neural network (CNN) and long-short-term memory (LSTM) architecture for predicting the spatiotemporal probability of infection spread using real-world pandemic data for future pandemics. This framework could aid designers, regulators, urban planners, and policymakers develop resilient, healthy, and sustainable urban spaces in post-COVID smart cities.
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Hypoxia-activated prodrugs are bioactivated in oxygen-deficient tumour regions and represent a novel strategy to exploit this pharmacological sanctuary for therapeutic gain. The approach relies on the selective metabolism of the prodrug under pathological hypoxia to generate active metabolites with the potential to diffuse throughout the tumour microenvironment and potentiate cell killing by means of a "bystander effect". In the present study, we investigate the pharmacological properties of the nitrogen mustard prodrug CP-506 in tumour tissues using in silico spatially-resolved pharmacokinetic/pharmacodynamic (SR-PK/PD) modelling. The approach employs a number of experimental model systems to define parameters for the cellular uptake, metabolism and diffusion of both the prodrug and its metabolites. The model predicts rapid uptake of CP-506 to high intracellular concentrations with its long plasma half-life driving tissue diffusion to a penetration depth of 190 µm, deep within hypoxic activating regions. While bioreductive metabolism is restricted to regions of severe pathological hypoxia (<1 µM O2), its active metabolites show substantial bystander potential with release from the cell of origin into the extracellular space. Model predictions of bystander efficiency were validated using spheroid co-cultures, where the clonogenic killing of metabolically defective "target" cells increased with the proportion of metabolically competent "activator" cells. Our simulations predict a striking bystander efficiency at tissue-like densities with the bis-chloro-mustard amine metabolite (CP-506M-Cl2) identified as a major diffusible metabolite. Overall, this study shows that CP-506 has favourable pharmacological properties in tumour tissue and supports its ongoing development for use in the treatment of patients with advanced solid malignancies.