Carbon Taxes and CO₂ Emissions Andersson, Julius J.
American economic journal. Economic policy,
11/2019, Letnik:
11, Številka:
4
Journal Article
Recenzirano
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This quasi-experimental study is the first to find a significant causal effect of carbon taxes on emissions, empirically analyzing the implementation of a carbon tax and a value-added tax on ...transport fuel in Sweden. After implementation, carbon dioxide emissions from transport declined almost 11 percent, with the largest share due to the carbon tax alone, relative to a synthetic control unit constructed from a comparable group of OECD countries. Furthermore, the carbon tax elasticity of demand for gasoline is three times larger than the price elasticity. Policy evaluations of carbon taxes, using price elasticities to simulate emission reductions, may thus significantly underestimate their true effect.
The persistence of carbonate structures on coral reefs is essential in providing habitats for a large number of species and maintaining the extraordinary biodiversity associated with these ...ecosystems. As a consequence of ocean acidification (OA), the ability of marine calcifiers to produce calcium carbonate (CaCO(3)) and their rate of CaCO(3) production could decrease while rates of bioerosion and CaCO(3) dissolution could increase, resulting in a transition from a condition of net accretion to one of net erosion. This would have negative consequences for the role and function of coral reefs and the eco-services they provide to dependent human communities. In this article, we review estimates of bioerosion, CaCO(3) dissolution, and net ecosystem calcification (NEC) and how these processes will change in response to OA. Furthermore, we critically evaluate the observed relationships between NEC and seawater aragonite saturation state (Ω(a)). Finally, we propose that standardized NEC rates combined with observed changes in the ratios of dissolved inorganic carbon to total alkalinity owing to net reef metabolism may provide a biogeochemical tool to monitor the effects of OA in coral reef environments.
It has been suggested that variation in brain structure correlates with the sizes of individuals' social networks. Whether variation in social network size causes variation in brain structure, ...however, is unknown. To address this question, we neuroimaged 23 monkeys that had been living in social groups set to different sizes. Subject comparison revealed that living in larger groups caused increases in gray matter in mid-superior temporal sulcus and rostral prefrontal cortex and increased coupling of activity in frontal and temporal cortex. Social network size, therefore, contributes to changes both in brain structure and function. The changes have potential implications for an animal's success in a social context; gray matter differences in similar areas were also correlated with each animal's dominance within its social network.
Artificial Earth Andersson, Johan Daniel
This work was supported by a fellowship at the Seed Box: A Mistra-Forman Environmental Humanities Collaboratory, Linköping University. Editing and final preparation of the manuscript was supported by the Swedish Energy Agency under Grant 46222-1 (MESAM) and the Swedish Research Council for Sustainable Development (Formas) under Grant 2019-01973,
2023
eBook, Book
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Artificial Earth: A Genealogy of Planetary Technicity offers an intellectual history of humanity as a geological force, focusing on a prevalent contradiction in the Anthropocene discourse on global ...environmental change: on the one hand, it has been argued that there are hardly any pristine environments anymore, to the degree that the concept of nature has lost its meaning; while on the other, that anthropogenic environmental change has become so prevailing that it ought to be conceived of as a force of nature, in the literal sense of the expression. Artificial Earth argues that to fully grasp the stakes of this discourse, we need not only understand the contemporary scientific and technological transformations behind the Anthropocene, but also explore the history of an ontological concern tied up with it. In order to do so, Artificial Earth examines reflections on the ontological dualism between nature and artifice within the history of earth science from the late eighteenth century onwards. Paying particular attention to its consequences for how human subjectivity has been conceptualized in the Anthropocene, it then enrolls these resources in an effort to problematize attempts since the 1980s to formalize earth science in systems theory terminology. In sum, the aim is to investigate the historical conditions for the possibility of conceiving human artifice as an integral part of the earth’s terrestrial environment, with the conviction that such an investigation may assist in resolving the aforementioned contradiction or at least to understand it better by tracing its historical lineage.
Ocean acidification refers to the lowering of the ocean's pH due to the uptake of anthropogenic CO
from the atmosphere. Coral reef calcification is expected to decrease as the oceans become more ...acidic. Dissolving calcium carbonate (CaCO
) sands could greatly exacerbate reef loss associated with reduced calcification but is presently poorly constrained. Here we show that CaCO
dissolution in reef sediments across five globally distributed sites is negatively correlated with the aragonite saturation state (Ω
) of overlying seawater and that CaCO
sediment dissolution is 10-fold more sensitive to ocean acidification than coral calcification. Consequently, reef sediments globally will transition from net precipitation to net dissolution when seawater Ω
reaches 2.92 ± 0.16 (expected circa 2050 CE). Notably, some reefs are already experiencing net sediment dissolution.
Lateral gene transfer in eukaryotes Andersson, J O
Cellular and molecular life sciences : CMLS,
06/2005, Letnik:
62, Številka:
11
Journal Article
Recenzirano
Lateral gene transfer -- the transfer of genetic material between species -- has been acknowledged as a major mechanism in prokaryotic genome evolution for some time. Recently accumulating data ...indicate that the process also occurs in the evolution of eukaryotic genomes. However, there are large rate variations between groups of eukaryotes; animals and fungi seem to be largely unaffected, with a few exceptions, while lateral gene transfer frequently occurs in protists with phagotrophic lifestyles, possibly with rates comparable to prokaryotic organisms. Gene transfers often facilitate the acquisition of functions encoded in prokaryotic genomes by eukaryotic organisms, which may enable them to colonize new environments. Transfers between eukaryotes also occur, mainly into larger phagotrophic eukaryotes that ingest eukaryotic cells, but also between plant lineages. These findings have implications for eukaryotic genomic research in general, and studies of the origin and phylogeny of eukaryotes in particular.
Modern tool materials, ranging from powder metallurgical high speed steel to super hard materials such as polycrystalline cubic boron nitride and diamond, are used as cutting tools in the metal ...cutting industry. In order to further improve the cutting performance, these tools are frequently coated by thin, hard PVD coatings such as TiN, TiAlN, AlCrO3, etc. In order to develop and design new PVD coatings it is important to characterize the mechanical properties of the coatings and understand the coating/substrate deformation mechanisms in a tribological contact, e.g. metal cutting. For example, it is important to be aware that the mechanical properties of the substrate (tool material) have a significant impact on the practical coating adhesion and the coating failure mechanisms.
In the present study scratch testing has been used in order to evaluate to increase the understanding of the mechanical response and potential coating failure modes of cathodic arc evaporated TiAlN deposited on high speed steel, cemented carbide and polycrystalline cubic boron nitride. Post-test characterization of the scratched samples using optical profilometry, scanning electron microscopy and energy dispersive X-ray spectroscopy were performed and the cohesive and adhesive surface failure mechanisms are described and related to the substrate material properties. The results clearly show that, although all substrate materials can be regarded as hard, they result in completely different coating failure mechanisms at the normal load corresponding to substrate exposure. Also, coating failure resulting in substrate exposure does not necessarily correspond to interfacial cracking resulting in adhesive fracture along the coating–substrate interface.
•The substrate material has a significant impact on coating failure mechanisms in scratch adhesion testing.•The practical adhesion of the TiAlN coating to the substrate increases in the order PCBN – HSS – CC.•For ductile substrates, the load carrying capacity (hardness) has a strong impact on practical adhesion.•For brittle-like substrates, the cohesive strength of the surface region has a strong impact on practical adhesion.
The anterior, mid, and posterior insula show differential structural and resting state connectivity with other pain-related brain regions.
Functional neuroimaging studies suggest that the anterior, ...mid, and posterior division of the insula subserve different functions in the perception of pain. The anterior insula (AI) has predominantly been associated with cognitive–affective aspects of pain, while the mid and posterior divisions have been implicated in sensory-discriminative processing. We examined whether this functional segregation is paralleled by differences in (1) structural and (2) resting state connectivity and (3) in correlations with pain-relevant psychological traits. Analyses were restricted to the 3 insular subdivisions and other pain-related brain regions. Both type of analyses revealed largely overlapping results. The AI division was predominantly connected to the ventrolateral prefrontal cortex (structural and resting state connectivity) and orbitofrontal cortex (structural connectivity). In contrast, the posterior insula showed strong connections to the primary somatosensory cortex (SI; structural connectivity) and secondary somatosensory cortex (SII; structural and resting state connectivity). The mid insula displayed a hybrid connectivity pattern with strong connections with the ventrolateral prefrontal cortex, SII (structural and resting state connectivity) and SI (structural connectivity). Moreover, resting state connectivity revealed strong connectivity of all 3 subdivisions with the thalamus. On the behavioural level, AI structural connectivity was related to the individual degree of pain vigilance and awareness that showed a positive correlation with AI-amygdala connectivity and a negative correlation with AI–rostral anterior cingulate cortex connectivity. In sum, our findings show a differential structural and resting state connectivity for the anterior, mid, and posterior insula with other pain-relevant brain regions, which might at least partly explain their different functional profiles in pain processing.
Worldwide, coral reef ecosystems are experiencing increasing pressure from a variety of anthropogenic perturbations including ocean warming and acidification, increased sedimentation, eutrophication, ...and overfishing, which could shift reefs to a condition of net calcium carbonate (CaCO3) dissolution and erosion. Herein, we determine the net calcification potential and the relative balance of net organic carbon metabolism (net community production; NCP) and net inorganic carbon metabolism (net community calcification; NCC) within 23 coral reef locations across the globe. In light of these results, we consider the suitability of using these two metrics developed from total alkalinity (TA) and dissolved inorganic carbon (DIC) measurements collected on different spatiotemporal scales to monitor coral reef biogeochemistry under anthropogenic change. All reefs in this study were net calcifying for the majority of observations as inferred from alkalinity depletion relative to offshore, although occasional observations of net dissolution occurred at most locations. However, reefs with lower net calcification potential (i.e., lower TA depletion) could shift towards net dissolution sooner than reefs with a higher potential. The percent influence of organic carbon fluxes on total changes in dissolved inorganic carbon (DIC) (i.e., NCP compared to the sum of NCP and NCC) ranged from 32% to 88% and reflected inherent biogeochemical differences between reefs. Reefs with the largest relative percentage of NCP experienced the largest variability in seawater pH for a given change in DIC, which is directly related to the reefs ability to elevate or suppress local pH relative to the open ocean. This work highlights the value of measuring coral reef carbonate chemistry when evaluating their susceptibility to ongoing global environmental change and offers a baseline from which to guide future conservation efforts aimed at preserving these valuable ecosystems.
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