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Exosomes are small extracellular vesicles (EVs), which have the diameter of 50–150 nm and originate from intralumenal vesicles in multivesicular endosomes (MVBs). Exosomes secreted from donor cells are delivered to recipient cells for transferring of exosome cargos, such as proteins, lipids and nucleic acids. The cargo transfer by exosomes has a pivotal role in cell-to-cell communication for many cellular processes; however, the detailed mechanism remains largely elusive. In our recent study, we found that RUBCN/rubicon regulates exosome secretion through endosomal recruitment of WIPI2, which promotes ESCRT-dependent MVB formation. We further showed that this pathway is essential for age-dependent increasing of exosomes, which transfer the pro-senescent microRNAs, including Mir26a and Mir486a, and accelerate cellular senescence in the recipient cells. Our findings highlight RUBCN’s key role in exosome secretion and its impact on cellular senescence, providing insights into its potential contributions to aging. [ABSTRACT FROM AUTHOR]

As the world grapples with the challenges of climate change, international cooperation and effective policy tools are crucial for reducing carbon emissions and achieving a sustainable future. This study uses a game-theoretical approach to investigate the negotiations between countries with high and low carbon dioxide emissions, with the goal of achieving zero carbon dioxide emissions by 2050. By fostering collaboration and understanding among nations, game theory provides a robust framework for addressing the complexities of global climate policy. Game theory provides a mathematical framework to model strategic behaviors in climate negotiations between high and low carbon dioxideemitting countries. By analyzing the payoff functions, the Nash equilibrium strategies for emission reduction efforts are derived. The introduction of a carbon tax increases the marginal cost of emissions, leading to higher equilibrium efforts by both country groups. Simulation results indicate a significant increase in emission reductions with the tax, demonstrating the tax's effectiveness in incentivizing climate action and contributing to global mitigation efforts. This result highlights the potential economic benefits of carbon taxation, including innovation incentives and reduced emissions, which can drive sustainable economic growth and job creation. However, the study also acknowledges potential costs, such as impacts on economic competitiveness and distributional fairness, which must be carefully considered and addressed in policy design. This research offers valuable insights for policymakers, highlighting the importance of crafting carbon tax policies that maximize environmental benefits while minimizing adverse economic and social effects. By balancing these considerations, policymakers can develop more effective strategies that support both environmental sustainability and economic resilience. [ABSTRACT FROM AUTHOR]

This paper investigates whether the euro or renminbi could join or even replace the US dollar as a dominant global reserve currency. The US dollar has long been dominant in international trade and finance, due to the size and stability of the US economy and the liquidity of US financial markets. The euro of the European Union (EU) and the renminbi of China challenge the hegemony of the US dollar. The Eurozone's institutional framework provides political stability and strong monetary authority, which make the associated currency, the euro, attractive as a potential reserve currency. China's rise as a global economic power promotes the use of its currency in international transactions, propelling global acceptance of the renminbi. China has explicitly challenged US dominance in many international arenas, including finance. In this paper, it is useful for an econophysics approach to measure the sign of the strength of coupling. This approach is adapted to define the divergence rate of the US dollar in relation to other currencies, specifically the euro and the renminbi, by quantifying how the dollar diverges over time based on currency indexes. It involves calculating forces that represent the divergence rates between the US dollar and these currencies, using a modified version of Coulomb's law. It also illuminates the dynamics of reserve currency competition, reaffirming the US dollar's central role in the global financial system from 2001 to 2022. Despite the emergence of potential challengers like the euro and renminbi, the dollar's dominance is likely to continue. As China's economy, international trade, and military power have expanded, the renminbi is increasingly seen as a potential reserve currency in the global financial system. However, China has shown a willingness to centralize political power, perhaps making other countries more likely to resist the renminbi becoming a reserve currency. The euro and renminbi do not present credible alternatives to the US dollar because (1) political fragmentation within the EU and differing fiscal policies among member states undermine the euro's reliability as a universal reserve asset, and (2) China enacts significant capital controls, lacks financial market transparency, and maintains a tight grip on economic policies. The US dollar's unparalleled liquidity, its deep financial markets, and America's geopolitical influence ensure the dollar's continued dominance as the world's primary reserve currency. The inherent structural and political challenges the euro and renminbi face make both unlikely to displace the dollar in the foreseeable future. Broader US hegemony, arising from it having the world's largest economy and strongest military, has supported the dollar's dominant role as a reserve currency, a dominance expected to endure. [ABSTRACT FROM AUTHOR]

This paper summarizes the results of an intercomparison project with Earth System Models of Intermediate Complexity (EMICs) undertaken in support of the Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report (AR5). The focus is on long-term climate projections designed to 1) quantify the climate change commitment of different radiative forcing trajectories and 2) explore the extent to which climate change is reversible on human time scales. All commitment simulations follow the four representative concentration pathways (RCPs) and their extensions to year 2300. MostEMICs simulate substantial surface air temperature and thermosteric sea level rise commitment following stabilization of the atmospheric composition at year-2300 levels. The meridional overturning circulation (MOC) is weakened temporarily and recovers to near-preindustrial values in most models for RCPs 2.6-6.0. The MOC weakening is more persistent for RCP8.5. Elimination of anthropogenic CO2 emissions after 2300 results in slowly decreasing atmospheric CO2 concentrations. At year 3000 atmospheric CO2 is still at more than half its year-2300 level in all EMICs forRCPs 4.5-8.5. Surface air temperature remains constant or decreases slightly and thermosteric sea level rise continues for centuries after elimination ofCO2 emissions in allEMICs.Restoration of atmosphericCO2 fromRCPto preindustrial levels over 100-1000 years requires large artificial removal of CO2 from the atmosphere and does not result in the simultaneous return to preindustrial climate conditions, as surface air temperature and sea level response exhibit a substantial time lag relative to atmospheric CO2. © 2013 American Meteorological Society.