BIOFUELS, CLIMATE POLICY, AND WATER MANAGEMENT: ASSESSING POLICY-INDUCED SHIFTS ON AGRICULTURE’S EXTENSIVE AND INTENSIVE MARGINS

Biofuel expansion efforts and climate mitigation policy could fundamentally alter land management trends in U.S. agriculture and forestry (AF) by mandating biofuel feedstock production and providing incentives for greenhouse gas (GHG) emissions reduction and carbon sequestration from terrestrial sources. Research has shown that biofuel expansion can alter commodity markets, induce agricultural land expansion, and intensify production. Meanwhile, GHG mitigation efforts could limit agricultural expansion, reduce current cultivation, and lower management intensity by incentivizing GHG emissions reduction and carbon sequestration within AF. To date, little work has attempted to quantify biofuel and climate policy-induced shifts together along the extensive and intensive agricultural production margins within a systems-based framework, though such shifts could have resounding implications on agricultural water consumption and quality. This study uses a comprehensive and detailed economic model of the U.S. AF sectors to simulate land management responses to biofuel expansion and GHG policies. While bioenergy production and altered AF management practices are found to significantly reduce GHG emissions, additional water consumption and nutrient use are possible policy outcomes. Specifically, we find that policies that influence shifts to the extensive margin will increase aggregate water use and nutrient application, but lead to lower intensity per-unit area. Conversely, when combined with biofuel mandates climate mitigation incentives lower agricultural land expansion, but lead to higher levels of management intensity. Somewhat contrary to expectations, GHG mitigation incentives cause water and nutrient use intensity to grow at an increasing rate due to the greater level of land use competition. Additionally, important regional trends emerge, as water use and quality concerns grow with the CO2 price in areas with limited GHG mitigation possibilities. This suggests that “water leakage” is possible whereby emissions reduction activities decrease output in one region and stimulate management intensity elsewhere. The potential indirect consequences of combined biofuel and climate mitigation incentives on water resource systems warrant further attention in policy design and future research.Greenhouse gas mitigation, biofuels, water resource management, Environmental Economics and Policy, Production Economics, Resource /Energy Economics and Policy,

Mitochondrial DNA and temperature tolerance in lager yeasts

A growing body of research suggests that the mitochondrial genome (mtDNA) is important for temperature adaptation. In the yeast genus Saccharomyces, species have diverged in temperature tolerance, driving their use in high- or low-temperature fermentations. Here, we experimentally test the role of mtDNA in temperature tolerance in synthetic and industrial hybrids (Saccharomyces cerevisiae × Saccharomyces eubayanus or Saccharomyces pastorianus), which cold-brew lager beer. We find that the relative temperature tolerances of hybrids correspond to the parent donating mtDNA, allowing us to modulate lager strain temperature preferences. The strong influence of mitotype on the temperature tolerance of otherwise identical hybrid strains provides support for the mitochondrial climactic adaptation hypothesis in yeasts and demonstrates how mitotype has influenced the world’s most commonly fermented beverage.This work was supported by the USDA National Institute of Food and Agriculture (Hatch project no. 1003258), the NSF (grant no. DEB-1253634), and in part by the DOE Great Lakes Bioenergy Research Center (DOE BER Office of Science; nos. DE-SC0018409 and DE-FC02-07ER64494). E.P.B. was supported by a Louis and Elsa Thomsen Wisconsin Distinguished Graduate Fellowship. C.T.H. is a Pew Scholar in the Biomedical Sciences and a Vilas Faculty Early Career Investigator, supported by the Pew Charitable Trusts and the Vilas Trust Estate. D.P. is a Marie Sklodowska-Curie fellow of the European Union’s Horizon 2020 research and innovation programme (grant agreement no. 747775). J.C.F. was supported by the NIH (no. GM080669)Peer Reviewe

BIOFUELS, CLIMATE POLICY, AND WATER MANAGEMENT: ASSESSING POLICY-INDUCED SHIFTS ON AGRICULTURE’S EXTENSIVE AND INTENSIVE MARGINS

Biofuel expansion efforts and climate mitigation policy could fundamentally alter land management trends in U.S. agriculture and forestry (AF) by mandating biofuel feedstock production and providing incentives for greenhouse gas (GHG) emissions reduction and carbon sequestration from terrestrial sources. Research has shown that biofuel expansion can alter commodity markets, induce agricultural land expansion, and intensify production. Meanwhile, GHG mitigation efforts could limit agricultural expansion, reduce current cultivation, and lower management intensity by incentivizing GHG emissions reduction and carbon sequestration within AF. To date, little work has attempted to quantify biofuel and climate policy-induced shifts together along the extensive and intensive agricultural production margins within a systems-based framework, though such shifts could have resounding implications on agricultural water consumption and quality. This study uses a comprehensive and detailed economic model of the U.S. AF sectors to simulate land management responses to biofuel expansion and GHG policies. While bioenergy production and altered AF management practices are found to significantly reduce GHG emissions, additional water consumption and nutrient use are possible policy outcomes. Specifically, we find that policies that influence shifts to the extensive margin will increase aggregate water use and nutrient application, but lead to lower intensity per-unit area. Conversely, when combined with biofuel mandates climate mitigation incentives lower agricultural land expansion, but lead to higher levels of management intensity. Somewhat contrary to expectations, GHG mitigation incentives cause water and nutrient use intensity to grow at an increasing rate due to the greater level of land use competition. Additionally, important regional trends emerge, as water use and quality concerns grow with the CO2 price in areas with limited GHG mitigation possibilities. This suggests that “water leakage” is possible whereby emissions reduction activities decrease output in one region and stimulate management intensity elsewhere. The potential indirect consequences of combined biofuel and climate mitigation incentives on water resource systems warrant further attention in policy design and future research

Integrative genomic mining for enzyme function to enable engineering of a non-natural biosynthetic pathway.

The ability to biosynthetically produce chemicals beyond what is commonly found in Nature requires the discovery of novel enzyme function. Here we utilize two approaches to discover enzymes that enable specific production of longer-chain (C5-C8) alcohols from sugar. The first approach combines bioinformatics and molecular modelling to mine sequence databases, resulting in a diverse panel of enzymes capable of catalysing the targeted reaction. The median catalytic efficiency of the computationally selected enzymes is 75-fold greater than a panel of naively selected homologues. This integrative genomic mining approach establishes a unique avenue for enzyme function discovery in the rapidly expanding sequence databases. The second approach uses computational enzyme design to reprogramme specificity. Both approaches result in enzymes with >100-fold increase in specificity for the targeted reaction. When enzymes from either approach are integrated in vivo, longer-chain alcohol production increases over 10-fold and represents >95% of the total alcohol products

Positive Reappraisals After an Offense: Event-related Potentials and Emotional Effects of Benefit-finding and Compassion

Using a within subjects design, three emotion regulation strategies (compassion‐focused reappraisal, benefit‐focused reappraisal, and offense rumination) were tested for their effects on forgiveness, well‐being, and event‐related potentials (ERPs). Participants (N = 37) recalled a recent interpersonal offense as the context for each emotion regulation strategy. Both decisional and emotional forgiveness increased significantly for the two reappraisal strategies compared to offense rumination. Compassion‐focused reappraisal prompted the greatest increase in both decisional and emotional forgiveness. Furthermore, both reappraisal strategies increased positively oriented well‐being measures (e.g., joy, gratitude) compared to offense rumination, with compassion‐focused reappraisal demonstrating the largest effect on empathy. Late positive potential (LPP) amplitudes in response to unpleasant affect words were larger following the benefit‐focused reappraisal strategy, indicating frontal LPP augmentation due to affective incongruence of the unpleasant stimuli with the positive, silver‐lining orientation of the benefit‐focused reappraisal emotion regulation strategy

Quantum Bubble Nucleation beyond WKB: Resummation of Vacuum Bubble Diagrams

On the basis of Borel resummation, we propose a systematical improvement of bounce calculus of quantum bubble nucleation rate. We study a metastable super-renormalizable field theory, $D$ dimensional O(N) symmetric $\phi^4$ model ($D<4$) with an attractive interaction. The validity of our proposal is tested in D=1 (quantum mechanics) by using the perturbation series of ground state energy to high orders. We also present a result in D=2, based on an explicit calculation of vacuum bubble diagrams to five loop orders.Comment: 19 pages, 5 figures, PHYZZ

Reduction in host-finding behaviour in fungus-infected mosquitoes is correlated with reduction in olfactory receptor neuron responsiveness

<p>Abstract</p> <p>Background</p> <p>Chemical insecticides against mosquitoes are a major component of malaria control worldwide. Fungal entomopathogens formulated as biopesticides and applied as insecticide residual sprays could augment current control strategies and mitigate the evolution of resistance to chemical-based insecticides.</p> <p>Methods</p> <p><it>Anopheles stephensi </it>mosquitoes were exposed to <it>Beauveria bassiana </it>or <it>Metarhizium acridum </it>fungal spores and sub-lethal effects of exposure to fungal infection were studied, especially the potential for reductions in feeding and host location behaviours related to olfaction. Electrophysiological techniques, such as electroantennogram, electropalpogram and single sensillum recording techniques were then employed to investigate how fungal exposure affected the olfactory responses in mosquitoes.</p> <p>Results</p> <p>Exposure to <it>B. bassiana </it>caused significant mortality and reduced the propensity of mosquitoes to respond and fly to a feeding stimulus. Exposure to <it>M. acridum </it>spores induced a similar decline in feeding propensity, albeit more slowly than <it>B. bassiana </it>exposure. Reduced host-seeking responses following fungal exposure corresponded to reduced olfactory neuron responsiveness in both antennal electroantennogram and maxillary palp electropalpogram recordings. Single cell recordings from neurons on the palps confirmed that fungal-exposed behavioural non-responders exhibited significantly impaired responsiveness of neurons tuned specifically to 1-octen-3-ol and to a lesser degree, to CO₂.</p> <p>Conclusions</p> <p>Fungal infection reduces the responsiveness of mosquitoes to host odour cues, both behaviourally and neuronally. These pre-lethal effects are likely to synergize with fungal-induced mortality to further reduce the capacity of mosquito populations exposed to fungal biopesticides to transmit malaria.</p

Improved Conformal Mapping of the Borel Plane

The conformal mapping of the Borel plane can be utilized for the analytic continuation of the Borel transform to the entire positive real semi-axis and is thus helpful in the resummation of divergent perturbation series in quantum field theory. We observe that the rate of convergence can be improved by the application of Pad\'{e} approximants to the Borel transform expressed as a function of the conformal variable, i.e. by a combination of the analytic continuation via conformal mapping and a subsequent numerical approximation by rational approximants. The method is primarily useful in those cases where the leading (but not sub-leading) large-order asymptotics of the perturbative coefficients are known.Comment: 6 pages, LaTeX, 2 tables; certain numerical examples adde

Renormalized couplings and scaling correction amplitudes in the N-vector spin models on the sc and the bcc lattices

For the classical N-vector model, with arbitrary N, we have computed through order \beta^{17} the high temperature expansions of the second field derivative of the susceptibility \chi_4(N,\beta) on the simple cubic and on the body centered cubic lattices. (The N-vector model is also known as the O(N) symmetric classical spin Heisenberg model or, in quantum field theory, as the lattice O(N) nonlinear sigma model.) By analyzing the expansion of \chi_4(N,\beta) on the two lattices, and by carefully allowing for the corrections to scaling, we obtain updated estimates of the critical parameters and more accurate tests of the hyperscaling relation d\nu(N) +\gamma(N) -2\Delta_4(N)=0 for a range of values of the spin dimensionality N, including N=0 [the self-avoiding walk model], N=1 [the Ising spin 1/2 model], N=2 [the XY model], N=3 [the classical Heisenberg model]. Using the recently extended series for the susceptibility and for the second correlation moment, we also compute the dimensionless renormalized four point coupling constants and some universal ratios of scaling correction amplitudes in fair agreement with recent renormalization group estimates.Comment: 23 pages, latex, no figure