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Abstract Rivers are pivotal in the global carbon cycle, transporting terrestrial carbon to the ocean while emitting significant amount of CO2 to the atmosphere. However, the partitioning of fluvial inorganic carbon (IC) between downstream transport and atmospheric evasion remains uncertain due to intricate hydrodynamic and biogeochemical processes. Inspired by Budyko's hydrological work, this study introduces a dimensionless framework to identify critical factors in fluvial IC partitioning: the IC fraction in equilibrium with the atmosphere and the ratio of advection to evasion timescales. River catchment analyses and modeling reveal that the equilibrium ratio determines the fraction of IC stably transported downstream. The hydrodynamic‐driven timescale ratio determines the fate of out‐of‐equilibrium IC, with low‐order streams favoring atmospheric evasion and higher‐order streams promoting downstream transport. This framework provides a simple yet robust approach to predicting river carbon dynamics, with implications for land‐to‐ocean transport, fluvial emissions, and climate mitigation strategies such as enhanced weathering.

Abstract Background The main drawback of BRAF/MEK inhibitors (BRAF/MEKi)-based targeted therapy in the management of BRAF-mutated cutaneous metastatic melanoma (MM) is the development of therapeutic resistance. We aimed to assess in this context the role of mTORC2, a signaling complex defined by the presence of the essential RICTOR subunit, regarded as an oncogenic driver in several tumor types, including MM. Methods After analyzing The Cancer Genome Atlas MM patients’ database to explore both overall survival and molecular signatures as a function of intra-tumor RICTOR levels, we investigated the effects of RICTOR downregulation in BRAFV600E MM cell lines on their response to BRAF/MEKi. We performed proteomic screening to identify proteins modulated by changes in RICTOR expression, and Seahorse analysis to evaluate the effects of RICTOR depletion on mitochondrial respiration. The combination of BRAFi with drugs targeting proteins and processes emerged in the proteomic screening was carried out on RICTOR-deficient cells in vitro and in a xenograft setting in vivo. Results Low RICTOR levels in BRAF-mutated MM correlate with a worse clinical outcome. Gene Set Enrichment Analysis of low-RICTOR tumors display gene signatures suggestive of activation of the mitochondrial Electron Transport Chain (ETC) energy production. RICTOR-deficient BRAFV600E cells are intrinsically tolerant to BRAF/MEKi and anticipate the onset of resistance to BRAFi upon prolonged drug exposure. Moreover, in drug-naïve cells we observed a decline in RICTOR expression shortly after BRAFi exposure. In RICTOR-depleted cells, both mitochondrial respiration and expression of nicotinamide phosphoribosyltransferase (NAMPT) are enhanced, and their pharmacological inhibition restores sensitivity to BRAFi. Conclusions Our work unveils an unforeseen tumor-suppressing role for mTORC2 in the early adaptation phase of BRAFV600E melanoma cells to targeted therapy and identifies the NAMPT-ETC axis as a potential therapeutic vulnerability of low RICTOR tumors. Importantly, our findings indicate that the evaluation of intra-tumor RICTOR levels has a prognostic value in metastatic melanoma and may help to guide therapeutic strategies in a personalized manner.

Summary: The definition of cell metabolic profile is essential to ensure skeletal muscle fiber heterogeneity and to achieve a proper equilibrium between the self-renewal and commitment of satellite stem cells. Heme sustains several biological functions, including processes profoundly implicated with cell metabolism. The skeletal muscle is a significant heme-producing body compartment, but the consequences of impaired heme homeostasis on this tissue have been poorly investigated. Here, we generate a skeletal-muscle-specific feline leukemia virus subgroup C receptor 1a (FLVCR1a) knockout mouse model and show that, by sustaining heme synthesis, FLVCR1a contributes to determine the energy phenotype in skeletal muscle cells and to modulate satellite cell differentiation and muscle regeneration.

A rapid and effective transition to low-carbon energy production is essential to limit climate change impacts. While the scientific community has mostly focused on research and development and techno-economic aspects, quantifying the role of public acceptability and policy in shaping emission trajectories has been much more elusive. This study investigates the coupled dynamics of nonlinear socio-political acceptance and anthropogenic CO _2 emissions, with implications for climate policies and clean energy investments. Our findings show that a top-down policy approach alone may not be sufficient for effective emission cuts, highlighting the need for a multi-level strategy that combines top-down and bottom-up approaches. Additionally, opinion polarization can trigger detrimental CO _2 emission oscillations when governments decide to take heavy-handed policy interventions in highly polarized socio-political systems. Delayed perception of climate change damage or abrupt reactions to extreme weather events may also significantly affect emission reduction efforts, although in the opposite direction. Integrating these socio-political dynamics into climate models can enhance our understanding of the complex interplay between human and natural systems, enabling the development of more effective and resilient mitigation strategies.

Rivers are pivotal in the global carbon cycle, transporting terrestrial carbon to the ocean while emitting significant amount of CO2 ${\mathrm{C}\mathrm{O}}_{2}$ to the atmosphere. However, the partitioning of fluvial inorganic carbon (IC) between downstream transport and atmospheric evasion remains uncertain due to intricate hydrodynamic and biogeochemical processes. Inspired by Budyko's hydrological work, this study introduces a dimensionless framework to identify critical factors in fluvial IC partitioning: the IC fraction in equilibrium with the atmosphere and the ratio of advection to evasion timescales. River catchment analyses and modeling reveal that the equilibrium ratio determines the fraction of IC stably transported downstream. The hydrodynamic‐driven timescale ratio determines the fate of out‐of‐equilibrium IC, with low‐order streams favoring atmospheric evasion and higher‐order streams promoting downstream transport. This framework provides a simple yet robust approach to predicting river carbon dynamics, with implications for land‐to‐ocean transport, fluvial emissions, and climate mitigation strategies such as enhanced weathering. Plain Language Summary: Rivers contain large amounts of dissolved inorganic carbon originating from the decomposition of organic matter and soil water fluxes. This carbon is partly transported downstream across the river network to the ocean and partly emitted as CO2 ${\mathrm{C}\mathrm{O}}_{2}$ to the atmosphere. Quantifying the partitioning between these fluxes is crucial for accurate carbon budgets from the local to the global scale, but the complex interplay of biogeophysical processes makes it challenging. Inspired by Budyko's seminal work in hydrology, we present a framework that determines the main chemical and physical processes governing the fluvial inorganic carbon partitioning. We identify two dimensionless numbers (or indexes) that can be defined with only a few parameters and provide quantitative and robust predictions on fluvial carbon fate. These numbers are linked to water turbulence and chemistry, and their values change across the river network. Key Points: Rivers partition inorganic carbon between downstream transport and CO2 ${\mathrm{C}\mathrm{O}}_{2}$ emissions to the atmosphereIncorporating key hydrodynamic and biogeochemical processes, we identify the dimensionless numbers that govern the inorganic carbon partitioningWater hydrodynamics plays a critical role in the fate of the carbon that is out of equilibrium with the atmosphere [ABSTRACT FROM AUTHOR]

Summary: Plant response to water stress involves multiple timescales. In the short term, stomatal adjustments optimize some fitness function commonly related to carbon uptake, while in the long term, traits including xylem resilience are adjusted. These optimizations are usually considered independently, the former involving stomatal aperture and the latter carbon allocation. However, short‐ and long‐term adjustments are interdependent, as 'optimal' in the short term depends on traits set in the longer term.An economics framework is used to optimize long‐term traits that impact short‐term stomatal behavior. Two traits analyzed here are the resilience of xylem and the resilience of nonstomatal limitations (NSLs) to photosynthesis at low‐water potentials.Results show that optimality requires xylem resilience to increase with climatic aridity. Results also suggest that the point at which xylem reach 50% conductance and the point at which NSLs reach 50% capacity are constrained to approximately a 2 : 1 linear ratio; however, this awaits further experimental verification.The model demonstrates how trait coordination arises mathematically, and it can be extended to many other traits that cross timescales. With further verification, these results could be used in plant modelling when information on plant traits is limited. [ABSTRACT FROM AUTHOR]

An overlooked phenomenon is a potential increase in the distribution and abundance of plants with the highly water-usage-efficient crassulacean acid metabolism (CAM). In the present article, we critically analyze recent research to investigate to what extent and why CAM plants may have recently expanded their range and abundance under global change. We discuss the ecophysiological and evolutionary mechanisms linked with CAM succulence and the drivers underlying potential CAM expansion, including drought, warming, and atmospheric carbon dioxide enrichment. We further map the biogeographic pattern of CAM expansion and show that some CAM plants (e.g. Cylindropuntia, Opuntia, and Agave) are expanding and encroaching within dryland landscapes worldwide. Our results collectively highlight the recent expansion of CAM plants, a trend that could be sustained under increasing aridity with climate change. We recommend that CAM expansion be evaluated in a data-model integrated framework to better understand and predict the ecological and socioeconomic consequences of CAM expansion during the Anthropocene. [ABSTRACT FROM AUTHOR]

Journals and citations are networks of practice in which management accounting, management control systems, and performance management carry significance. A total of 2,560 publications and 43,425 citations from the Web of Science between 2000-2020 were used to perform a citation analysis of articles, authors, and journals, along with a bibliometric study to map keywords co-occurrence. Citations and publications had an explosive growth due to new journals and Web of Science expansion, with the number and share of top journals decreasing over time. Performance management is eclectic with journals and authors from various disciplines; bibliometric maps suggest that management accounting and performance literature rooted in strategy are competing to integrate this emerging topic. Regardless of the increase in citations and publications, there are only 28 Latin American articles (1% of the total). Despite calls for more diversity in accounting research, we observe the pre-eminence of Western academic norms and practices. Although management accounting is an active field in Latin America with many local publications, few appear in internationally ranked academic journals. [ABSTRACT FROM AUTHOR]

Helmholtz formalism provides a tantalizing interpretation of classical thermodynamics, based on time integrals of purely mechanical quantities and without need of statistical description. Here we extend this approach to include heat flux and pressure at the walls to enable it to describe actual thermodynamic transformations, such as isothermal compressions and expansions. The presence of hard walls, which gives rise to non zero pressure, is justified by means of the virial theorem, while the heat fluxes are introduced as quasi-static limits of suitably thermostatted Hamiltonians. Particular attention is paid to generalizing the minimalist cases of the harmonic oscillator and elastic bouncer, which afford clear physical interpretations. With such extensions, a complete picture of thermodynamics emerges, amenable to phase transitions and cyclic deterministic transformations, which produce mechanical work from heat, like the Carnot cycle. [Display omitted] • Helmholtz thermodynamics is extended to include effects of walls (i.e., pressure) and heat transfer. • real thermodynamic transformations and phase transition. • deterministic Carnot cycle with thermostatted elastic bouncer. [ABSTRACT FROM AUTHOR]

The physical significance of the stochastic processes associated to the generalized Gibbs ensembles is scrutinized here with special attention to the thermodynamic fluctuations of small systems. Differently from the so-called stochastic thermodynamics, which starts from stochastic versions of the first and second law of thermodynamics and associates thermodynamic quantities to microscopic variables, here we consider stochastic variability directly in the macroscopic variables. By recognizing the potential structure of the Gibbs ensembles, when expressed as a function of the potential entropy generation, we obtain exact nonlinear thermodynamic Langevin equations (TLEs) for macroscopic variables, with drift expressed in terms of entropic forces. The analysis of the canonical ensemble for an ideal monoatomic gas and the related TLEs show that introducing currents leads to nonequilibrium heat transfer conditions with interesting bounds on entropy production but with no obvious thermodynamic limit. For a colloidal particle under constant force, the TLEs for macroscopic variables are different from those for the microscopic position, typically used in stochastic thermodynamics; while TLEs are consistent with the fundamental equation obtained from the Hamiltonian, stochastic thermodynamics requires isothermal conditions and entropy proportional to position.