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This paper examines how enhanced flexibility across space, time, and a regulatory dimension affects the economic costs and CO 2 emissions of integrating large shares of intermittent renewable energy from wind and solar. We develop a numerical model which resolves hourly dispatch and investment choices among heterogeneous energy technologies and natural resources in interconnected wholesale electricity markets, cross-country trade (spatial flexibility), energy storage (temporal flexibility), and tradable green quotas (regulatory flexibility). Taking the model to the data for the case of Europe's system of interconnected electricity markets, we find that the appropriate combination of flexibility can bring about substantial gains in economic efficiency, reduce costs (up to 13.8%) and lower CO 2 emissions (up to 51.2%). Regulatory flexibility is necessary to realize most of the maximum possible benefits. We also find that gains from increased flexibility are unevenly distributed and that some countries incur welfare losses. [ABSTRACT FROM AUTHOR]

Infections with intestinal nematodes have an equivocal impact: they represent a burden for human health and animal husbandry, but, at the same time, may ameliorate auto-immune diseases due to the immunomodulatory effect of the parasites. Thus, it is key to understand how intestinal nematodes arrive and persist in their luminal niche and interact with the host over long periods of time. One basic mechanism governing parasite and host cellular and tissue functions, metabolism, has largely been neglected in the study of intestinal nematode infections. Here we use NADH (nicotinamide adenine dinucleotide) and NADPH (nicotinamide adenine dinucleotide phosphate) fluorescence lifetime imaging of explanted murine duodenum infected with the natural nematode Heligmosomoides polygyrus and define the link between general metabolic activity and possible metabolic pathways in parasite and host tissue, during acute infection. In both healthy and infected host intestine, energy is effectively produced, mainly via metabolic pathways resembling oxidative phosphorylation/aerobic glycolysis features. In contrast, the nematodes shift their energy production from balanced fast anaerobic glycolysis-like and effective oxidative phosphorylation-like metabolic pathways, towards mainly anaerobic glycolysis-like pathways, back to oxidative phosphorylation/aerobic glycolysis-like pathways during their different life cycle phases in the submucosa versus the intestinal lumen. Additionally, we found an increased NADPH oxidase (NOX) enzymes-dependent oxidative burst in infected intestinal host tissue as compared to healthy tissue, which was mirrored by a similar defense reaction in the parasites. We expect that, the here presented application of NAD(P)H-FLIM in live tissues constitutes a unique tool to study possible shifts between metabolic pathways in host-parasite crosstalk, in various parasitic intestinal infections. [ABSTRACT FROM AUTHOR]

Employing a numerical general equilibrium model with multiple fuels, end-use sectors, heterogeneous households, and transport externalities, this paper examines three motives for differentiated carbon pricing in the context of Swiss climate policy: fiscal interactions with the existing tax code, non-CO2 related transport externalities, and social equity concerns. Interaction effects with mineral oil taxes reduce carbon taxes on motor fuels and transport externalities increase them. We show that the cost-effective overall carbon tax on motor fuels should be lower than the one on thermal fuels. This is found in spite of the fact that pre-existing taxes on motor fuels are well below our estimate of the transport externality per unit of transport fuel consumption. Differentiating taxes in favor of motor fuels yields only slightly more equitable incidence effects among households, suggesting that equity considerations play a minor role when designing differentiated carbon pricing policies. [ABSTRACT FROM AUTHOR]

Collective movement of epithelial cells drives essential multicellular organization during various fundamental physiological processes encompassing embryonic morphogenesis, cancer and wound healing. Yet the molecular mechanism that ensures the coordinated movement of many cells remains elusive. Here we show that a tumour suppressor protein, merlin, coordinates collective migration of tens of cells, by acting as a mechanochemical transducer. In a stationary epithelial monolayer and also in three-dimensional human skin, merlin localizes to cortical cell-cell junctions. During migration initiation, a fraction of cortical merlin relocalizes to the cytoplasm. This relocalization is triggered by the intercellular pulling force of the leading cell and depends on the actomyosin-based cell contractility. Then in migrating cells, taking its cue from the intercellular pulling forces, which show long-distance ordering, merlin coordinates polarized Rac1 activation and lamellipodium formation on the multicellular length scale. Together, these results provide a distinct molecular mechanism linking intercellular forces to collective cell movements in migrating epithelia. [ABSTRACT FROM AUTHOR]

Because human activities emit greenhouse gases (GHGs) and conventional air pollutants from common sources, policy designed to reduce GHGs can have co-benefits for air quality that may offset some or all of the near-term costs of GHG mitigation. We present a systems approach to quantify air quality co-benefits of US policies to reduce GHG (carbon) emissions. We assess health-related benefits from reduced ozone and particulate matter (PM2.5) by linking three advanced models, representing the full pathway from policy to pollutant damages. We also examine the sensitivity of co-benefits to key policy-relevant sources of uncertainty and variability. We find that monetized human health benefits associated with air quality improvements can offset 26-1,050% of the cost of US carbon policies. More flexible policies that minimize costs, such as cap-and-trade standards, have larger net co-benefits than policies that target specific sectors (electricity and transportation). Although air quality co-benefits can be comparable to policy costs for present-day air quality and near-term US carbon policies, potential co-benefits rapidly diminish as carbon policies become more stringent. [ABSTRACT FROM AUTHOR]

Inflammatory bowel disease (IBD) is a chronic disease arising due to a culmination of genetic, environmental, and lifestyle-associated factors and resulting in an excessive pro-inflammatory response to bacterial populations in the gastrointestinal tract. The prevalence of IBD in developing nations is relatively low, and it has been proposed that this is directly correlated with a high incidence of helminth infections in these areas. Gastrointestinal nematodes are the most prevalent parasitic worms, and they efficiently modulate the immune system of their hosts in order to establish chronic infections. Thus, they may be capable of suppressing unrelated inflammation in disorders such as IBD. This review describes how nematodes, or their products, suppress innate and adaptive pro-inflammatory immune responses and how the mechanisms involved in the induction of anti-nematode responses regulate colitis in experimental models and clinical trials with IBD patients. We also discuss how refinement of nematode-derived therapies should ultimately result in the development of potent new therapeutics of clinical inflammatory disorders. [ABSTRACT FROM AUTHOR]

This paper develops a decomposition algorithm by which a market economy with many households may be solved through the computation of equilibria for a sequence of representative agent economies. The paper examines local and global convergence properties of the sequential recalibration (SR) algorithm. The SR algorithm is then demonstrated to efficiently solve Auerbach–Kotlikoff OLG models with a large number of heterogeneous households. We approximate equilibria in OLG models by solving a sequence of related Ramsey optimal growth problems. This approach can provide improvements in both efficiency and robustness as compared with integrated complementarity-based solution methods. [ABSTRACT FROM AUTHOR]

Collaborating under the Modeling Platform (SEMP), five modeling teams (employing an energy systems model and four macroeconomic models with a focus on energy) have carried out a multi-model comparison to assess the economic and technological consequences of reaching emission reduction targets for 2050 in the context of Switzerland. We consider different designs of carbon taxes to compare their economic cost: economy-wide or sector-specific carbon taxes with or without an emission trading system (ETS) in place. All models find that the climate targets can be reached at modest welfare reductions of 0.15–0.37% (if targeting 1.5 tonnes of CO 2 per capita) or 0.24–0.48% (if targeting 1.0 tonnes per capita) compared to a business-as-usual scenario in which the emission level of 1.5 tonnes per capita is exceeded by 83–137%. In contradiction to the additional target of reducing Swiss electricity use, most models find it cost-effective to replace some of the energy supplied by fossil fuels by electricity and thus do not recommend a decrease in electricity use. Most models find that a uniform carbon tax is the most efficient instrument to achieve the emission reduction targets. Those models with a detailed representation of pre-existing mineral oil taxes find that in early periods of climate policy, taxing emission from transport fuels at lower rates than other emissions may be cost-efficient. This effect vanishes as the stringency of targets and thus CO 2 taxes increase over time. [ABSTRACT FROM AUTHOR]