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A shift from fossil fuel to renewable energy is crucial in achieving climate goals of 2 degrees Celsius. However, the renewable energy technologies, solar photovoltaics, wind turbines, and electric vehicles are metal-intensive, while the mining and smelting processes to obtain the relevant metals are emissions-intensive. We estimate future PM2.5 emissions from mining and smelting to meet the metal demand of renewable energy technologies in two climate pathways to be around 0.3-0.6 Tg/yr in the 2030-2040 period, which could be around 10-30% of total anthropogenic PM2.5 emissions in many countries in those years. The concentration of mineral reserves in a few regions means the impacts are also regionally concentrated. The regional distributions of global emissions relative to metal demand depend on the metal production regionality and emission abatement measures. Stronger emissions abatement could reduce metal-related emissions by over 90% and avoid emission hotspot creation.

BACKGROUND The INGEVITY lead (Boston Scientific, St Paul, MN, USA) has excellent clinical performance. However, its single filar design results in decreased lead tensile strength and a possible challenging extraction. This study's goal is to evaluate techniques for extracting the INGEVITY lead. METHODS Two- and three-dimensional models were created to simulate lead extraction from a right atrial appendage lead implant with a left subclavian approach and lead/fibrosis attachment sites. Standard and unique lead extraction preparation strategies were evaluated. Traction forces were measured from a superior approach alone or in combination with a femoral approach. RESULTS For lead extraction via the superior approach, leaving the terminal on the lead was the only factor influencing maximum tolerated load (p-value = .0007). Scar attachment provided greater lead tensile strength by transferring traction loading forces to the polyurethane outer insulation but dependent on insulation integrity. The strongest extraction rail was seen with a simulated femoral snaring of a locking stylet within the INGEVITY lead. Deployed screw retraction was most successful by rotating a Philips LLD#2 stylet (Philips Healthcare, Amsterdam, Netherlands) within the lead. CONCLUSION Results from in vitro simulations of INGEVITY lead extraction from an atrial location found the lead has low maximum tensile strength resulting in a poor extraction rail with common extraction tools and methods. However, the strength of the INGEVITY Lead extraction rail can be significantly increased by leaving the lead terminal intact and femoral snaring of the locking stylet within the lead. Such techniques may improve extraction of the INGEVITY lead.

Modern experimental technologies can assay large numbers of biological sequences, but engineered protein libraries rarely exceed the sequence diversity of natural protein families. Machine learning (ML) models trained directly on experimental data without biophysical modeling provide one route to accessing the full potential diversity of engineered proteins. Here we apply deep learning to design highly diverse adeno-associated virus 2 (AAV2) capsid protein variants that remain viable for packaging of a DNA payload. Focusing on a 28-amino acid segment, we generated 201,426 variants of the AAV2 wild-type (WT) sequence yielding 110,689 viable engineered capsids, 57,348 of which surpass the average diversity of natural AAV serotype sequences, with 12-29 mutations across this region. Even when trained on limited data, deep neural network models accurately predict capsid viability across diverse variants. This approach unlocks vast areas of functional but previously unreachable sequence space, with many potential applications for the generation of improved viral vectors and protein therapeutics.

Lead extraction procedures have a low but real risk of major complications, such as superior vena cava tear and cardiac tamponade. Complications during lead removal are commonly related to lead binding sites, lead malposition, and lead perforation. Lead extraction imaging may indicate lead vascular binding sites, lead position, and perforation. Several imaging modalities are available, including chest radiograph, cardiac computed tomography, and echocardiography. The information provided by various imaging modalities will help assess the challenges of each lead extraction procedure and allows for better preprocedure planning.