An Adversarial Risk Analysis Framework for Cybersecurity

Risk analysis is an essential methodology for cybersecurity as it allows organizations to deal with cyber threats potentially affecting them, prioritize the defense of their assets, and decide what security controls should be implemented. Many risk analysis methods are present in cybersecurity models, compliance frameworks, and international standards. However, most of them employ risk matrices, which suffer shortcomings that may lead to suboptimal resource allocations. We propose a comprehensive framework for cybersecurity risk analysis, covering the presence of both intentional and nonintentional threats and the use of insurance as part of the security portfolio. A simplified case study illustrates the proposed framework, serving as template for more complex problems.

Multinuclear PtII Complexes: Why Three is Better Than Two to Enhance Photophysical Properties

The self-assembly of platinum complexes is a well-documented process that leads to interesting changes of the photophysical and electrochemical behavior as well as to a change in reactivity of the complexes. However, it is still not clear how many metal units must interact in order to achieve the desired properties of a large assembly. This work aimed to clarify the role of the number of interacting PtII units leading to an enhancement of the spectroscopic properties and how to address inter- versus intramolecular processes. Therefore, a series of neutral multinuclear PtII complexes were synthesized and characterized, and their photophysical properties at different concentration were studied. Going from the monomer to dimers, the growth of a new emission band and the enhancement of the emission properties were observed. Upon increasing the platinum units up to three, the monomeric blue emission could not be detected anymore and a concentration independent bright-yellow/orange emission, due to the establishment of intramolecular metallophilic interactions, was observed.

Methane emissions from tree stems in neotropical peatlands

Neotropical peatlands emit large amounts of methane (CH₄ ) from the soil surface, but fluxes from tree stems in these ecosystems are unknown. In this study we investigated CH₄ emissions from five tree species in two forest types common to neotropical lowland peatlands in Panama. Methane from tree stems accounted for up to 30% of net ecosystem CH₄ emissions. Peak CH₄ fluxes were greater during the wet season when the water table was high and temperatures were lower. Emissions were greatest from the hardwood tree Campnosperma panamensis, but most species acted as emitters, with emissions declining exponentially with height along the stem for all species. Overall, species identity, stem diameter, water level, soil temperature and soil CH₄ fluxes explained 54% of the variance in stem CH₄ emissions from individual trees. On the landscape level, On the landscape level, the high emissions from C. panamensis forests resulted in that they emitted at 340 kg CH₄  d^-1 during flooded periods despite their substantially lower areal cover. We conclude that emission from tree stems is an important emission pathway for CH₄ flux from Neotropical peatlands, and that these emissions vary strongly with season and forest type.

Negative feedback processes following drainage slow down permafrost degradation

The sustainability of the vast Arctic permafrost carbon pool under climate change is of paramount importance for global climate trajectories. Accurate climate change forecasts, therefore, depend on a reliable representation of mechanisms governing Arctic carbon cycle processes, but this task is complicated by the complex interaction of multiple controls on Arctic ecosystem changes, linked through both positive and negative feedbacks. As a primary example, predicted Arctic warming can be substantially influenced by shifts in hydrologic regimes, linked to, for example, altered precipitation patterns or changes in topography following permafrost degradation. This study presents observational evidence how severe drainage, a scenario that may affect large Arctic areas with ice-rich permafrost soils under future climate change, affects biogeochemical and biogeophysical processes within an Arctic floodplain. Our in situ data demonstrate reduced carbon losses and transfer of sensible heat to the atmosphere, and effects linked to drainage-induced long-term shifts in vegetation communities and soil thermal regimes largely counterbalanced the immediate drainage impact. Moreover, higher surface albedo in combination with low thermal conductivity cooled the permafrost soils. Accordingly, long-term drainage effects linked to warming-induced permafrost degradation hold the potential to alleviate positive feedbacks between permafrost carbon and Arctic warming, and to slow down permafrost degradation. Self-stabilizing effects associated with ecosystem disturbance such as these drainage impacts are a key factor for predicting future feedbacks between Arctic permafrost and climate change, and, thus, neglect of these mechanisms will exaggerate the impacts of Arctic change on future global climate projections.

Cap-independent translation ensures mTOR expression and function upon protein synthesis inhibition

The mechanistic/mammalian target of rapamycin (mTOR) is a conserved serine/threonine kinase that integrates cellular signals from the nutrient and energy status to act, namely, on the protein synthesis machinery. While major advances have emerged regarding the regulators and effects of the mTOR signaling pathway, little is known about the regulation of mTOR gene expression. Here, we show that the human mTOR transcript can be translated in a cap-independent manner, and that its 5' untranslated region (UTR) is a highly folded RNA scaffold capable of binding directly to the 40S ribosomal subunit. We further demonstrate that mTOR is able to bypass the cap requirement for translation both in normal and hypoxic conditions. Moreover, our data reveal that the cap-independent translation of mTOR is necessary for its ability to induce cell-cycle progression into S phase. These results suggest a novel regulatory mechanism for mTOR gene expression that integrates the global protein synthesis changes induced by translational inhibitory conditions.